Boards Prep: Ocular Anatomy: Book

Question 1

Define the following:

1. Telecanthus
2. Poliosis
3. Madarosis
   a. Most common causes (3)
   b. Most Dangerous cause?
4. Trichiasis
5. Phthiriasis Palpebrarum

Answer 1

1. Increased distance b/w Medial Canthi
2. Whitening of Eyelashes
3. Loss of eyelashes
   a. Bad MGD, Dry Eye, Posterior Blepharitis

b. Sebaceous Gland Carcinoma
4. Eyelashes turn inward (usually secondary to Entropion)
5. Infection of Eyelashes: Due to Phthiriasis Pubis

Question 2

1. Why is the Skin layer of the Eyelid so unique? (what is different from it and the skin of the rest of the body)
2. What is the Subcutaneous Layer?
3. Orbicularis Layer?

Answer 2

1. THINNEST…(no fat…)
2. Loose CT b/w outer skin and orbicularis. This layer on UPPER LID contains the LEVATOR APONEUROSIS as it travels to insert on the UPPER TARSAL PLATE
3. Location of PALPEBRAL PORTION of ORBICULARIS OCULI

Question 3

1. What happens to the Eyelids if the Orbicularis Oculi is Paralyzed?

Answer 3

1. The Lower eyelid will droop away from the Globe –> ECTROPION

Question 4

Orbicularis Oculi

1. Orbital Portion: Function?
2. Palpebral Portion: Function
   a. What 2 parts does it contain?

Answer 4

1. FORCED CLOSURE of EYELIDS (underneath eyebrow…attaches to orbital margins)
2. SPONTANEOUS and REFLEX BLINKING
   a. Muscle of RIOLAN (Pars Ciliaris) and Muscle of Horner (Pars Lacrimalis)

Question 5

Orbicularis Oculi

1. Muscle of Riolan (Pars Ciliaris)
   a. Superficial part of this muscle: What does it do?
   b. The most anterior portion of the muscle of Riolan is the GRAY LINE: Purpose?
2. Muscle of Horner (Pars Lacrimalis)
   a. Think “H”…what does “H”orner’s muscle “H”elp do?
   b. Where is it found?

Answer 5

1. a. Keeps LID MARGIN tightly applied to the GLOBE during eye movements.
   b. Found b/w meibomian glands and eyelashes. Divides lid into Ant and Post Portions. It’s a Landmark during SURGERY for lid repairs.
2. a. “H”elps DRAIN TEARS into Lacrimal Sac.
   b. Around the Canaliculi

Question 6

What are the Layers of the Eyelid? (8)

**Try and Tell the “story of each layer and what makes each layer unique/what their purpose(s) is/are!

Answer 6

1. Skin Layer
2. Subcutaneous Areolar Layer
3. Orbicularis Layer
4. Submuscular Areolar Layer
5. Orbital Septum
6. Posterior Muscular System
7. Tarsal Plate
8. Palpebral Conjunctiva

Question 7

Eyelids: Submucsular Areolar Layer

1. What is it?
2. The upper lid submuscular areolar layer contains what 2 things?
3. What 2 things are present in this layer in both upper and lower eyelids?

Answer 7

1. another thin loose CT layer b/w Orbicularis and Orbital Septum
2. Levator Aponeurosis and Palpebral portion of the main lacrimal gland
3. Peripheral and Margin Arcades

Question 8

Eyelid: Orbital Septum

1. What is its PURPOSE?
2. What is it?
3. Periorbita: What does it cover?
   a. Projects Anteriorly to become what?
   b. Projects Posteriorly to become what?
4. Orbital Septum: Continuous with what 2 things of the skull?
   a. Where does it attach medially?
   b. Does the Lacrimal Sac get protected as well?
   c. The Superior Orbital Septum is an Insertion site for what MUSCLE?

Answer 8

1. BARRIER to INFECTION and FAT (prevents Orbital Fat Prolapse)
2. Dense, Irregular, CT
3. Orbital Bones
   a. Orbital Septum
   b. it fuses w/the DURA of the ON
4. Periorbita and Periosteum of the Skull
   a. Posterior Lacrimal Crest
   b. No. It’s anterior to this.
   c. Levator Aponeurosis

Question 9

Eyelid: Posterior Muscular System

1. What 3 muscles does this refer to?

Answer 9

1. Superior Levator Palpebrae
2. Superior Tarsal Muscle (Muller’s)
3. Inferior Tarsal Muscle

Question 10

Eyelid: Posterior Muscular System

1. Superior Palpebral Levator Muscle
   a. From what bony structure does it ORIGINATE?
   b. Purpose? (mm?)
   c. Whitnall’s Ligament: Purpose

d. When this muscle hits Whitnall’s Ligament, what it extends to the eyelid as what?
e. How is the SUPERIOR PALPEBRAL FURROW Formed?
f. How is the INFERIOR PALPEBRAL FURROW formed?
g. What do these furrows separate?

Answer 10

1. a. Lesser wing of Sphenoid at Orbital Apex
   b. Main RETRACTOR of UPPER EYELID (15 mm)
   c. Acts as a Fulcrum: Changes muscle course from Ant-Post to Sup-Inf so it can function.
   d. a Fan-Shaped Tendon (LEVATOR APONEUROSIS).
   e. via Insertion of the Levator Aponeurosis into the skin of the UPPER EYELID.
   f. thru INDIRECT Attachment of the IR into the skin of the lower eyelid.
   g. Tarsal and Orbital Portions of the Eyelid.

Question 11

Eyelid: Posterior Muscular System

• Both are SNS innervated
  1. Muscle of Muller (INVOLUNTARY)

a. Type of Muscle?
b. Receptors at this muscle?
c. What can block these receptors?
d. Purpose?
e. Called the MINOR RETRACTOR? How much does it widen the palpebral fissure?

f. Originates from what?

2. Inferior Levator Muscle: Purpose
   a. Originates from?

Answer 11

1. a. Smooth
   b. a2 receptors
   c. Aproclonidine (Iopidine) and Brimonidine (Alphagan)
   d. (MAINTAINS EYE BEING OPEN) Widens palpebral fissure
   e. 1-3 mm of the upper eyelid lift.

f. on Levator. Extends into Tarsal Plate.

2. Minor lower lid retraction
   a. Fascial Sheath of IR. Extends into tarsal plate

Question 12

Eyelids:

1. Horner’s: Lack of Sympathetic Inn to Muller and Inf Tarsal muscle: What happens?
2. CN 3 Palsy: due to No Parasympathetic inn to LEVATOR: Causes what?
3. TED: “stare appearance” due to what?
4. Normal Interpalpebral Fissure DISTANCE in ADULTS?

Answer 12

1. MILD UPPER LID PTOSIS; REVERSE PTOSIS of LOWER EYELID
2. BIG UPPER PTOSIS
3. RETRACTION of MUSCLE OF MULLER
4. 10-12 mm

Question 13

Eyelid: Tarsal Plate

1. What is it?
   a. What does it surround?
2. Upper and Lower Tarsal Plates combine MEDIALLY and LATERALLY to form what?
   a. What does each attach to?

Answer 13

1. Dense, Irregular CT…RIGIDITY to EYELIDS
   a. Meibomian Glands (Horiz and Vert Collagen Fibrils)
2. Medial and Lateral PALPEBRAL LIGAMENTS
   a. Medial Ligament: Maxillary Bone; Lateral: Whitnall’s Ligament

Question 14

Eyelid: Palpebral Conjunctiva (inner lining of eyelids that contain 2 layers)

1. Epithelial Layer
   a. What is it?
   b. Contains what CELLS? Found mainly where?
2. Stroma
   a. Type of CT?
   b. Made up of 2 layers of what?

Answer 14

1. a. Stratified protective layer (into Fornices and onto the Bulbar Conjunctiva)
   b. GOBLET CELLS (make Mucin); found mainly in Inferonasal Fornix and Bulbar Conj (most concentrated TEMPORALLY)
2. a. Loose Vascularized CT
   b. Superficial Lymphoid Layer (IMMUNOLOGICALLY ACTIVE: IgA, Macrophages, Mast Cells, PMNs, Eosinophils)

and Deep Fibrous Layer (Connects Conj to internal structures. Has ACCESSORY LACRIMAL GLANDS, Nerves, and BVs of eyelids. Gets continuous w/Dense CT of Tarsal Plate)

Question 15

Glands of Eyelid and Conjunctiva

1. Meibomian Glands
   a. How many are there on the upper eyelid?
   b. Lower Eyelid?
2. Glands of Zeis
   a. What are they?
   b. How many around each eyelash?
3. Glands of Moll
   a. What are they?
   b. Purpose?
4. ALG: What does it stand for?
   a. Glands of Krause: Where found and what do they do?
   b. Glands of Wolfring: Location: Purpose?

Answer 15

1. a. ~25
   b. ~20
2. a. Modified Sebaceous Glands
   b. 2. Lubricate them…prevent them from getting brittle
3. a. Modified Apocrine Glands (Near LID MARGIN)
   b. Dump stuff onto eyelash follicles, Zeis Glands, and Lid Margin
4. Accessory Lacrimal Glands
   a. FORNICES of the CONJ. (Merocrine glands. Secrete same stuff as Lacrimal Gland)

b. Larger…More numerous than the others. Found in TARSAL CONJUNCTIVA.

Question 16

Tear Summary

1. Lipid: 3 types of glands?
2. Aqueous (REM)
   a. MLG (RE)
   b. ALG (M)
3. Mucous: What glands?

Answer 16

1. Meibomian Glands, Zeiss and Moll
2. a. Reflexive and Emotional
   b. Maintenance
3. Goblet Cells

Question 17

1. What 2 glands are HOLOCRINE GLANDS? (Whole cell secretion)
2. What 2 glands are APOCRINE GLANDS? (Part of Plasma Membrane buds off cell and goes into lumen)
3. What glands are MEROCRINE GLANDS? (secretes content via exocytosis…whole cell intact)

Answer 17

1. Meibomian Glands and Glands of Zeis
2. Glands of Moll and Goblet Cells
3. Accessory Lacrimal Glands

Question 18

Nerves of the Eyelids

1. Nerve that innervates the Orbicularis Oculi?
   a. Voluntary/Involuntary Motor?
2. What innervates the Muscle of Muller?
   a. Voluntary/Involuntary Motor?
3. Upper Eyelid
   a. V1: (NFL): What branches of each?
   b. NFL = ?
4. Lower Eyelid
   a. V2: Innervated by what Branches?

Answer 18

1. Zygomatic Branch of FACIAL NERVE
   a. Voluntary
2. SNS
   a. Involuntary
3. a. Lacrimal (Lacrimal Gland); Frontal (Supraorbital and Supratrochlear Nerves); Nasociliary (Infratrochlear Nerve)
   b. Nasociliary, Frontal, and Lacrimal Nerves
4. a. Infraorbital and Zygomatic Nerves

Question 19

Arterial Supply to Eyelids

1. Where are the Palpebral Arcades located in the upper and lower Eyelids?
   a. What are they formed by?
2. The MEDIAL Palpebral Artery is a branch off of what artery?
3. What about the LATERAL Palpebral Artery?
4. What do the Arcades supply?
5. What Palpebral Arcades are located CLOSEST to the Eyelid Margin?
6. What arteries supply the FORNICES and Posterior Conjunctiva?
   a. What do they connect to (and what do these arteries supply)?

Answer 19

1. in Submucosal Areolar Layer
   a. Medial and Lateral Palpebral Arteries
2. Ophthalmic Artery
3. Lacrimal Artery
4. Deep Eyelid Structures
5. MARGINAL Palpebral Arcades
6. PALPEBRAL Palpebral Arcades
   a. Anterior Ciliary Arteries (Anterior part of the CONJ…Bulbar Conj and Ciliary Body…Reason why Pts w/UVEITIS can experience Circumlimbal Injection and Decreased Aq. Humor Production in that eye)

Question 20

Veins of the Eyelids

1. They parallel the Arteries and drain into what 2 veins?
2. Lateral Lymphatics drain into what?
3. Medial Lymphatics drain into what?

Answer 20

1. Palpebral and Ophthalmic Veins
2. Parotid (Preauricular) Lymph Nodes
3. Submandibular Lymph Nodes

Question 21

Eyebrows

1. Purpose (2)
2. Frontalis: Purpose?
   a. Origin?
   b. Insertion?
   c. Usually used to compensate for what?
   d. How do fibers run?
3. Corrugator: Purpose?
   a. How do fibers run?
   b. What does it do? (“C”) (Facial expression type?)
   c. Origin?
   d. Insertion?
4. “PRO”cerus: Purpose? (PRO Football Player)
   a. Origin?
   b. Insertion?
   c. What does it do?
   d. Facial Expression (PRO Football Player…)
5. Orbicularis Oculi: Purpose?

Answer 21

1. Protection and Facial Expression
2. Main Elevator of eyebrows and forehead
   a. High on Scalp
   b. Near Superior Orbital Rim
   c. Ptosis
   d. Vertically
3. MEDIAL DEPRESSOR of the eyebrow (Helps protect from sun glare)
   a. Oblique
   b. Concentration/Sorrow
   c. Frontal Bone
   d. Skin above Medial Eyebrows
4. MEDIAL DEPRESSOR of eyebrow
   a. Nasal Bone (Nose bridge)
   b. Frontalis Muscle b/w Eyebrows on each side of the midline
   c. Makes Horizontal FURROWS over the bridge of the nose
   d. MENACE/AGGRESSION
5. Primary LATERAL DEPRESSOR of the Eyebrow

Question 22

1. Lacrimal Gland
   a. Location?
   b. Divided into Orbital and Palpebral Portion by the tendon of what muscle?
   c. Releases Product thru what Secretion type?
   d. Innervation type from what nerve?
   e. Artery/Vein that supplies it?
   f. Dz: ACUTE DACRYOADENITIS: What is it?

Answer 22

1. a. Fossa of Frontal Bone
   b. Superior Levator Palpebrae Muscle
   c. Merocrine Secretion
   d. PSNS Inn via LACRIMAL NERVE of CN7 via Pterygopalatine Ganglion
   e. Lacrimal Artery/Vein and contains the ONLY Lymph vessels of the orbit (drains to Parotid Lymph Nodes)
   f. Infection/Inflammation of Lacrimal Gland: causes Acute Swelling and pain in upper lateral eyelid

Question 23

2. Nasolacrimal Drainage System
   a. Lacrimal Puncta: What is responsible for keeping the Puncta open?
   b. Length of Canaliculi?
   c. What muscle surrounds the canaliculi?
   d. Lacrimal Sac: Length? Lined by what cells?
   d. 10-12 mm; Double Epithelium (Superficial Columnar and Deep Basal Layers), Microvilli, Goblet Cells.
   e. Is the Lacrimal Sac protected by the Orbital septum?f. How does the Lacrimal Sac get divided?
   g. Dz: Dacryocystitis: What is it?
   h. Nasolacrimal Duct: Lies Adjacent to what? Length? Lined with what? Duct terminates into what?
   i. Valve of Hasner: What does it do?
   j. NLDO: Adults (2)
   k. NLDO: Kids (1)

Answer 23

2. a. LACRIMAL PAPILLA
   b. 10 mm. 2 mm vertical then 8 mm horizontal
   c. Muscle of HORNER (Helps drain TEARS)
   d. 10-12 mm; Double Epithelium (Superficial Columnar and Deep Basal Layers), Microvilli, Goblet Cells.
   e. NO! the septum is Posterior to the sac.
   f. Medial Palpebral Ligament (medial upper and lower tarsal plates)…divides into 2 sections in front of and behind the sac. Muscle of Horner surrounds the Lacrimal Sac, divides it into upper and lower sections
   g. Infection of Lacrimal Sac. Usually due to Nasolacrimal Duct Obstruction (Involutional = Old)
   h. to MAXILLARY SINUS; 15 mm; Double Epithelium, microvilli, goblet cells; Into Inferior meatus of Nasal Cavity
   i. Prevents back flow of nasal fluids into the lacrimal drainage system
   j. Stenosis and Sinusitis
   k. Valve of Hasner (1/3 born w/o opening)

Question 24

Orbit

3. a. Contents (5)
   b. Fat: Intraconal
   c. Fat: Extraconal
   d. EOMs: Better in every way than Skeletal muscles
   e. EOM: SR: Origin? Insertion? Sheath on SR connects to sheaths of what?

f. EOM: LR: Origin? Insertion? What does the Lateral Check Ligament do?

Answer 24

a. Globe, EOMs, ON and smaller nerves, CT, Fat
b. w/in muscle cone of 4 recti muscles. Separates them from ON.
c. Outside muscle cone, b/w EOMs and Orbit Walls
d. Denser Blood supply, Nerve supply; Faster, More fatigue resistant
e. CTR Ant to Sup Orbital Fissure; 7.7 mm from limbus; to that of Superior Levator Palpebrae muscle and CT of Sup Conjunctival Fornix
f. CTR at Spina Recti Lateralis; 6.9 mm from limbus; Anchors LR to Whitnall’s Tubercule on Zygomatic Bone of the orbit.

Question 25

Orbit

g. EOM: IR: Origin? Insertion? Combines with what sheath?
h. EOM: MR: Origin? Insertion? Medial Check Ligament anchors MR to what?
i. All recti insertions on the globe form what?
j. EOM: SO: Origin? Travels anteriorly before looping thru the trochlea to insert on what? What is considered the physiologic origin of the SO?
k. EOM: IO: Origin? Insertion?
l. EOM: ALL EOM Tendons PIERCE WHAT? What does this DO?

Answer 25

g. CTR at Infraoptic Tubercule; 6.5 mm from limbus; IO Sheath forming Ligament of Lockwood which attaches to inf tarsal plate, and extends from zygomatic bone of the lateral wall to lacrimal bone of medial wall to give support to the wall.
h. CTR; 5.5 from the limbus; to Medial Orbital Septum, bone behind posterior lacrimal crest, caruncle, and plica semilunaris.
i. the SPIRAL of TILLAUX
j. Lesser wing of sphenoid and CTR; on the Superior Lateral Globe behind the Equator; TROCHLEA
k. Anteriorly at maxillary bone; Inferior lateral globe behind the equator
l. TENON’s CAPSULE; Sends some CT w/Tendons for a short distance BEFORE they merge with the SCLERA.

Question 26

Orbit

m: EOM: Blood Supply: SUPERIOR LATERAL BRANCH (3)
n. EOM: Blood Supply: Inferior Medial Branch (3)
o. EOM: Blood: What 3 other arteries may give a minor blood supply to the EOMs
p. EOM: Nerves: Superior Division of CN 3?
q. EOM: Nerves: Inferior Division of CN 3?
r. Orbital Fascia (Periorbita/Orbital Periosteum): What is it?; Purpose?; Continuous with what?
s. Orbital Fascia: w/in the Optic Canal, it’s continuous w/what?; Helps form what?
t. Orbital Fascia: Part of it covers what 3 other things?
u. Orbital Fascia: Anterior Orbital Fascia forms what? Purpose?

Answer 26

m. SR, LR, SO
n. MR, IR, IO
o. Lacrimal, Supraorbital, and Infraorbital Arteries
p. SR
q. IR, IO, MR
r. Dense CT covers Orbit; Support for BVs and attachment points for muscles, tendons, and ligaments; w/Periosteum of skull and bones of the face
s. Dura mater; CTR
t. Lacrimal Gland, Lacrimal Sac, and helps line the nasolacrimal canal
u. ORBITAL SEPTUM in U/L Eyelids; Barrier to prevent fat prolapse and orbital infections.

Question 27

4. Anatomic Relationships among Orbital Structures
   a. Sphenoid: Pituitary gland can cause what kind of VF Defect?
   b. Sphenoid: Where is the OPTIC CANAL LOCATED?; What passes thru?
   c. Sphenoid: Has what 3 foramina and what passes thru them? (ROS)
   d. Sphenoid: SOF: Location?; What lies just POSTERIOR to the SOF?
   e. CTR: What is it?; Location?; Origin of what?;
   f. SOF and CTR: What passes thru ABOVE the CTR but w/in SOF? (SOV, FLighT)
   g. What passes thru the SOF AND the CTR? (NOA)
   h. What passes thru the IOF and BELOW the CTR (IOV)

Answer 27

4. a. Bitemporal Hemianopsia (damage Nasal retinal fibers)
   b. w/in Lesser Wing; ON and Ophthalmic Artery
   c. Foramen Rotundum: V2; Formaen Ovale: V3 and Petrosal Nerve; Foramen Spinosum: Meddle Meningeal Artery
   d. b/w Greater/Lesser wings of Sphenoid; Cavernous sinus
   e. CT; Anterior to SOF; of RECTI MUSCLES
   f. Superior Ophthalmic Vein, Frontal nerve, Lacrimal nerve, and Trochlear nerve.
   g. Nasociliary Nerve, Occulomotor Nerve, and Abducens Nerve
   h. Inferior Ophthalmic Vein, and sometimes the Central Retinal Vein if it hasn’t already joined w/the Ophthalmic Vein.

Question 28

5. Foramens and Openings of the Orbit
   a. Optic Canal (foramen): 2
   b. Carotid Canal: (2)
   c. Supraorbital Foramen: 3
   d. Infraorbital Foramen: 3
   e. Mandibular Foramen: 2
   f. Stylomastoid Foramen: 1

Answer 28

a. ON and Ophthalmic Artery
b. ICA and Sympathetic Plexus (MOOCH: 1: ICA; 2: CN3: Meuller’s; CN5: Dilator)
c. Supraorbital Nerve (V1) and Supraorbital Artery and Vein
d. Infraorbital Nerve (V2) and Infraorbital Artery and Vein
e. Inferior Alveolar Nerve and Vessel
f. Facial Nerve (Right in front of the EAR!)

Question 29

Bones of the Orbit

1. Roof: What part serves as floor of the frontal sinus?
2. Floor: The orbital Floor serves as the roof of what?
   a. What bone comprises the majority of the orbital floor?
   b. Which bone is the weakest?
   c. What nerve passes thru?
   d. Orbital Floor Fracture can cause what 2 things to happen?
3. Medial Wall: Thinnest?
   a. Ethmoid bone: AKA?
4. Lateral: This is what?
5. Most common BENIGN ORBITAL TUMORS in Adults?
6. Most common BENIGN Orbital Tumors in Children?

Answer 29

1. Anterior portion of Frontal Bone
2. of the Maxillary Sinus
   a. Maxillary Bone
   b. Maxillary
   c. Infraorbital Nerve –> Infraorbital Groove –> Exits orbit via Infraorbital Foramen
   d. Muscle entrapment and Endophthalmos
3. (Ethmoid bone) but also this is the Thinnest and smallest wall of the orbit.
   a. Lamina Papyracea (#1 cause/location of Orbital Cellulitis)
4. Strongest Wall in the Orbit
5. Cavernous Hemangiomas
6. Capillary Hemangiomas

Question 30

Blood Supply: External Carotid Artery

1. Blood to what locations?
   a. What’s the most important branch of the ECA?
   b. And the 2 most important Terminal Branches?

Answer 30

1. Superficial Areas of Neck and Head. Small amt to Ocular Structures
   a. Facial Artery
   b. Superficial Temporal Artery and Maxillary Artery

Question 31

Blood Supply: ECA

1. Facial Artery
   a. What is the TERMINAL Branch of the Facial Artery?
   b. Where does this artery branch at and travel to?
2. Maxillary Artery
   a. Terminal Branch of ECA: Starts just anterior to what structure?
   b. What branch supplies the IR and IO
   c. This same branch exits thru the Infraorbital Foramen and supplies what 2 structures before joining w/the Angular Artery (from facial artery) and dorsal nasal Artery (from ophthalmic artery)
3. Superficial Temporal Artery
   a. Terminal branch of ECA that comes from within what structure?
   b. It has 3 branches that supply what 3 structures?
   c. This artery communicates w/branches from what artery?

Answer 31

1. a. ANGULAR ARTERY (Supplies MEDIAL CANTHUS)
   b. Angle of Mandible –> Over Mandible –> Medial Canthus
2. a. Parotid Gland
   b. Infraorbital Branch of the maxillary artery
   c. LOWER EYE LID and LACRIMAL SAC
3. a. Parotid Gland
   b. Superficial Skin, Muscles, and Soft tissue around the face and orbit.
   c. Ophthalmic Artery

Question 32

GCA:

1. Damage to what Arteries (think CIRCLE of ZINN), causes irreversible damage of the ONH?

Answer 32

1. SPCAs (AAION)

Question 33

ICA

1. Terminal Branches of the Ophthalmic Artery help with what other artery in giving circulation to superficial areas of the face and orbit?
2. Purpose of Anastomosing ECA branches w/ICA branches?

Answer 33

1. ECA

2. To give some supply if one is blocked. (Ex: Superficial Termporal artery and Supraorbital Artery anastomose).

Question 34

Course and Branches of the ICA

1. ICA enters skull thru the Petrous Portion of the Temporal Bone and travels directly to what?
2. What CN travels alongside the ICA?
3. What CN travels LATERAL to the ICA?
4. What CN travels MEDIAL to the ICA just before it exits the Cavernous Sinus?
5. What is the FIRST Branch of the ICA?
6. An aneurysm of the ICA w/in the CAVERNOUS SINUS will Most likely affect which CN?

Answer 34

1. Cavernous Sinus
2. 6
3. 3
4. 2
5. Ophthalmic Artery
6. CN 6

Question 35

Opthalmic Artery (1)

1. This artery enters the ORBIT w/in what?
2. After leaving the ON Sheath, it travels near what WALL of the ORBIT? (B/w what EOMs)?
3. Inner Retina: Supplied by what ARTERY branch?
   a. This sends blood to what 2 areas of the RETINA?
4. Outer Retina: Blood supply from where?
   a. SPCA (LIGHTS OUT!): Supplies blood to what 3 structures?
   b. LPCA: Supplies Blood to what 2 Structures?
5. What receptors are found on MACI?
6. What receptors are found on NPCE?
7. CAIs work where? Name them.

Answer 35

1. ON Sheath
2. MEDIAL WALL (SO and MR)
3. Central Retinal Artery (CRA)
   a. NFL and INL
4. Choroid
   a. Posterior Choroid, Circle of Zinn (ONH) and Macula
   b. Anterior Choroid and MACI
5. A-2 receptors
6. B-2 Receptors
7. CA (which brings Bicarbonate into in); Diamox, TRUSOPT and AZOPT (?)

Question 36

Ophthalmic Artery (2): Branches

1. CRA
   a. Supplies what part of the RETINA?
   b. Travels w/in ON and supplies nerve and pia mater via collateral branches. Enters Optic DISC how?
2. Lacrimal Artery
   a. Travels along what orbital wall (along with what nerve)?
   b. Supplies what 2 structures with blood?
   c. Terminates as branches of what? (This supplies what 2 structures)?
   d. How are the PALPEBRAL ARCADES formed?
3. Muscular Artery
   a. Gives blood to EXTRAOCULAR MUSCULES via 2 branches:
   i. Superior Lateral Muscles Artery supplies what structures (Muscles)
   ii. Inferior Medial Muscular Artery supplies what muscles?
   b. Branches of the muscular artery that supply the 4 RECTI MUSCLES form what?
   i. What does this combine with to FORM MACI?

Answer 36

1. a. INNER 2/3 of RETINA
   b. Slightly NASAL to CENTER then divides into multiple Sup and Inf Branches
2. a. LATERAL (Lacrimal Nerve)
   b. Lacrimal Gland and LR
   c. of the Lateral Palpebral Artery (Lateral Inf and Sup Lids)
   d. Lateral Palpebral Arteries anastomose w/Medial Palpebral Arteries (from DORSONASAL ARTERY (from ECA))
3. a. i. SR, SO, LR, and Levator Muscle
   ii. IR, IO, MR
   b. ANTERIOR CILIARY ARTERIES (ACA)
   i. LPCA

Question 37

Ophthalmic Artery (3): Branches 2

1. SPCAs
   a. Supplies what 3 structures?
   b. 1-2 large branches enter the eye on both sides of the ON then branch 10-20 times w/in what?
2. LPCAs
   a. How does it enter each eye? (Similar to SPCAs)
   b. Travels b/w what eye structures?
   c. They join the SPCAs to form what Network of blood?
   d. LPCAs supply blood to what structures?
3. Where is MACI’s located?
   a. What kind of capillaries does it have? Purpose?
4. Supraorbital Artery
   a. Blood to what structures w/in the Orbit?
   b. Then it exits the orbit and supplies blood to what?
5. Ethmoid Artery
   a. Blood to what 3 structures?

Answer 37

1. a. Macula, Circle of Zinn (ONH), and Posterior Choroid
   b. w/in Choroidal Stroma to form the arterial network (Circle of Zinn)
2. a. 2 arteries enter each eye on each side of the ON
   b. Sclera and Choroid
   c. Network of Blood to the CHOROID!
   d. Iris, CB, Ant Choroid (Join with ACA to form MACI)
3. w/in CB
   a. FENESTRATED CAPILLARIES; Lets plasma leak out (helps form Aq. Humor)
4. a. SR, SO, and Levator muscles
   b. Superficial Scalp and Forehead
5. a. Ethmoid, Frontal, and Sphenoid Sinuses

Question 38

Ophthalmic Artery (4): TERMINAL BRANCHES

1. Supratrochlear Artery
   a. Supplies blood to what? (3)
2. Dorsal Nasal Artery
   a. Blood to what?
   b. Travels along the side of the nose to join what artery?
   c. This artery branches into what to join with what later to form the PALPEBRAL ARCADES?
3. OIS: Due to what?
   a. What kind of HEMES are seen?

Answer 38

1. a. Forehead Skin, Scalp, and Muscles of the forehead.
2. a. Lacrimal Sac
   b. Angular Artery
   c. Into MEDIAL PALPEBRAL ARTERIES (suppliy medial sup and inf eyelids); join w/Lateral Palpebral arteries.
3. Occlusion of ICA or Ophthalmic Artery
   a. U/L Mid PERIPHERAL HEMES

Question 39

Venous Drainage of the Eye

1. Does venous drainage of the orbit correspond to arterial supply?
2. CRV: Drains blood from what layers of the Retina?
   a. How does it exit?
3. CRVOs and BRVOs are secondary to formation of what w/in veins?
   a. What is the MAJOR threat to vision in Pts w/a CRVO? (what can develop?)
4. Anterior Ciliary Veins
   a. Drain blood from what structures?
   b. These Veins follow the path of Anterior Ciliary Arteries across what?
   c. What 2 veins do they drain into?
5. Vortex Veins
   a. Drain blood from what?
   b. How many present?
   c. They drain into what veins?

Answer 39

1. NO!
2. Inner 6 Layers
   a. ON –> Cavernous Sinus –> Joins w/Superior Ophthalmic Vein
3. Thrombus Formation
   a. Neovascular Glaucoma (90 Day Glaucoma)
4. a. From Anterior Structures of the Eye (Iris, CB, Conj, Schlemm’s Canal)
   b. Tendons of the 4 recti muscles
   c. Sup and Inf Ophthalmic Veins
5. a. Choroid
   b. 1 in each quadrant, sometimes more
   c. Sup and Inf Ophthalmic Veins

Question 40

Venous Drainage of the Eye (2): Superior Ophthalmic Vein

1. Sup Ophthalmic Vein (Largest vein in Orbit)
   a. Does majority of blood drainage in eye from what veins? (4)
2. The Superior Root of SOV originates at what structure?
   a. From what branches?
3. Where does the Inferior Root of the SOV originate from?
4. These 2 roots JOIN Together to form the SOV where?
5. Where does the SOV exit the orbit thru and where does it drain into?

Answer 40

1. a. CRV, Sup Vortex Veins, Muscular Veins (SR and MR), Ant Ciliary Arteries and Lacrimal Vein
2. Superomedial Orbital Rim
   a. Supraorbital and Supratrochlear Veins (drain blood from forehead and scalp)
3. Branches of the Angular Vein (which is a branch from the Facial Vein)
4. Posterior to the Trochlea; Medial to the SR insertion
5. SOF; Cavernous Sinus

Question 41

Venous Drainage of the Eye (3): Inf Ophthalmic Vein

1. Originates from what?
2. What veins drop blood into the IOV?
3. 2 Branches formed:
   a. Inf Branch: Exits the orbit thru what and drains into what?

b. Sup Branch exits orbit thru what and drains into what?

Answer 41

1. Diffuse network of veins along the Anterior Medial Orbital Floor b/w the Globe and the IR
2. Muscle veins (MR,LR, IR, IO and Ant Ciliary Veins), Inf Vortex Veins, Small veins draining Inf Conj., Lower Eyelid and Lacrimal Sac
3. a. Inf Orbital Fissure; Pterygoid Plexus
   b. SOF; Cavernous Sinus (Then joins w/SOV)

Question 42

Superficial Veins of Orbit and Face (1)

1. Supraorbital Vein
   a. Origin?
   b. Sends a branch thru what?
2. Frontal Vein
   a. Origin?
   b. Communicates with what vein?
   c. Then Joins with what vein? (what location?); What does it form?
3. Angular Vein
   a. Origin?
   b. Sends a Nasofrontal branch into the orbit that joins with what? (to form what vein?)
   c. This vein eventually becomes what vein?
4. Anterior Facial Vein
   a. Receives blood from what 3 veins?
   b. Travels along the masseter then joins with what vein? (forming what vein, which drains into what vein?)

Answer 42

1. a. Forehead; Joins Frontal Vein near Medial Angle of the Orbit to form the ANGULAR VEIN
   b. Supraorbital Notch that helps form SOV
2. a. Venous Plexus on the forehead
   b. Superficial Temporal Vein
   c. Supraorbital Vein (Medial Angle of the Orbit); Angular Vein
3. a. Side of the nose and Medial Angle of the Orbit
   b. with the Supraorbital Branch (SOV)
   c. Anterior Facial Vein at the lower margin of the orbit
4. a. Branch of the Pterygoid Venous Plexus, Sup and Inf Palpebral Veins
   b. Posterior Facial Vein (Common Facial Vein which drains into the INTERNAL JUGULAR VEIN)

Question 43

Superficial Veins of Orbit and Face (2)

1. Infraorbital Vein
   a. Origin
   b. Travel?
   c. Receives blood from?
2. Pterygoid Venous Plexus
   a. Location?
   b. Communicates with what veins?
   c. This eventually forms what vein?

Answer 43

1. a. Superficial veins that drain the face
   b. Infraorbital Foramen –> Orbit–> Floor of Orbit w/in Infraorbital groove and canal
   c. Structures of Inferior Orbit then Empties into Pterygoid Venous Plexus
2. a. Infratemporal Fossa
   b. Anterior Facial Vein and Cavernous Sinus (thru Orbital and Emissary Veins of the cranium)
   c. Maxillary Vein

Question 44

Superficial Veins of Orbit and Face (3)

1. Superficial Temporal Vein
   a. Origin?
   b. Frontal branches and Parietal branches of the Venous Plexus join to form the trunk of what vein?
   c. Communicates with what veins?
   d. Joins with what Vein w/in the Parotid Gland to form what vein?
2. Middle Temporal Vein receives blood from what which originates where?

Answer 44

1. a. Venous Plexus on the side of the skull
   b. Superficial Temporal Vein
   c. Frontal, Supraorbital, Posterior Auricular, Middle Temporal, and Occipital Veins
   d. Maxillary vein; Form Posterior Facial Vein
2. ORBITAL VEIN; from Lateral Palpebral Venous branches

Question 45

Superficial Veins of Orbit and Face (4)

1. Posterior Facial Vein (Retromandibular Vein)
   a. Formed by what 2 veins coming together?
   b. Divides into 2 branches
   i. Anterior Branch unites with what vein, to form what vein? This drains into what vein?

ii. Posterior Branch: Joins with what veins? Communicates with what 2 veins? Forms What vein?

Answer 45

1. a. Superficial Temporal Vein and Maxillary Vein w/in Parotid Gland
   b. i. Anterior Facial Vein; Common Facial Vein; INTERNAL JUGULAR VEIN

ii. Posterior Auricular Vein; Occipital and Superficial Temporal Veins; EXTERNAL JUGULAR VEIN

Question 46

Superficial Veins of Orbit and Face (5)

1. Occipital Vein
   a. Origin
   b. It will do 1 of 2 things: 1: It can drain DIRECTLY to what VEIN? or 2: It joins with the Posterior Auricular to drain into what VEIN?
2. How is the External Jugular Vein Formed?
   a. Drains blood from where?
3. Internal Jugular Vein: How is it formed?
   a. Drains blood from what 5 VEINS?

Answer 46

1. a. Posterior Vertex of the skull
   b. Internal Jugular Vein; External Jugular Vein
2. Retromandibular vein and Posterior Auricular Vein join
   a. Superficial FACE
3. Continuation of the SIGMOID SINUS
   a. Common Facial, Lingual, Medial Thyroid, Superior Thyroid and Occipital Veins

Question 47

Dural Sinuses of the Head (1)

1. What are they?
   a. Lined with what cells?
   b. Continuous with what of veins?
   c. Do they have VALVES?
   d. Purpose?

Answer 47

1. Venous Channels in dura mater of the brain
   a. Endothelium
   b. Endothelium of veins
   c. NO
   d. Drain blood from head –> Heart

Question 48

Dural Sinuses: Cavernous Sinus (2)

1. Location: B/w what bones?
   a. Begins just posterior to what opening?
   b. Extends to what part of the Temporal Bone?
   c. What is superior to the Cavernous Sinus?
   d. What is inferior to the Cavernous Sinus?
2. Receives blood from what 4 veins?
3. What does the Cavernous Sinus drain into (what 2 sinuses)?
   a. To what vein does it eventually drain into?
4. The Cavernous Sinus: Can also communicate with what Plexus?
   a. Via what veins? (These exit the skull thru what 2 holes)
5. What does the TRIANGLE OF DEATH refer to?
   a. Why?

Answer 48

1. Sphenoid and Temporal Bones
   a. SOF
   b. Petrous Portion
   c. Optic Chiasm
   d. Sphenoid Sinus
2. SUP and INF OPHTHALMIC VEINS, Superficial middle cerebral vein, and Inf Cerebral Veins
3. Sup and Inf Petrosal Sinuses
   a. INTERNAL JUGULAR VEIN
4. Pterygoid Plexus
   a. Emissary Veins (Foramen Ovale and Foramen Lacerum)
5. Corners of the mouth to the bridge of the nose
   a. Infections here can get into the Brain via the CAVERNOUS SINUS thru the facial vein communicating w/the Opthalmic Veins

Question 49

Dural Sinuses (3)

1. Tolosa-Hunt Syndrome
   a. What is it?
   b. What CNs can be affected (4)?
   c. What are the 2 signs seen?
2. Carotid-Cavernous Fistula (CCF)
   a. Cause?
   b. Signs/Symptoms (3)?

Answer 49

1. a. Inflammation of SOF and/or Cavernous Sinus
   b. 3-6
   c. PAINFUL EXTERNAL OPHTHALMOPLEGIA and DIPLOPIA
2. a. Abnormal communication b/w Arterial and Venous Blood supplies w/in the Cavernous Sinus
   b. PAINFUL RED EYE, ORBITAL BRUIT, and PULSATILE PROPTOSIS

Question 50

Dural Sinuses (4)

1. Superior Petrosal Sinus
   a. Drains blood from what 2 vein types?
   b. Communicates with what 2 sinuses?
2. Inferior Petrosal Sinus
   a. Origin?
   b. Gets blood from what 3 veins?
   c. This sinus exits the SKULL thru what foramen?
   d. Drains into what VEIN?

Answer 50

1. a. Inferior Cerebral Veins and some Cerebellar Veins
   b. Cavernous Sinus and Transverse Sinus
2. a. Posterior Inferior Portion of the Cavernous Sinus
   b. Internal Auditory Veins, and veins from the Brainstem and Cerebellum
   c. Jugular Foramen
   d. Internal Jugular Vein

Question 51

Dural Sinuses (5)

1. Superior Sagittal Sinus
   a. Location?
   b. Drains blood from what veins (1)?
   c. Travels posteriorly to what?
   d. Drains into what sinus?
2. Inferior Sagittal Sinus
   a. Travels w/in Inf portion of Falx Cerebri b/w what bones?
   b. Gets blood from what veins (1)?
   c. Travels posteriorly to join the Great Cerebral Vein to MAKE what SINUS?
3. Straight Sinus
   a. Origin?
   b. Drains blood from what veins?
   c. Drains into what Sinus?

Answer 51

1. a. Superior FALX CEREBRI on upper petrous portion of temporal bone
   b. Superior Cerebral Veins
   c. to the Internal Occipital Protuberance
   d. Right Transverse Sinus
2. a. Occipital and Petrous Portion of the Temporal Bone
   b. Inferior Cerebral Veins
   c. STRAIGHT SINUS
3. a. Junction of Falx Cerebri and TENTORIUM (CT that separates brain and cerebellum)
   b. Superior Cerebellar Veins
   c. Left Transverse Sinus

Question 52

Dural Sinuses (6)

1. Occipital Sinus
   a. Origin?
   b. Gets blood from what veins?
   c. Drains into what Sinus?
2. Transverse Sinus
   a. Origin (ish)
   b. Gets blood from what sinus and what 2 veins?
   c. Travels inferiorly and forms what Sinus?
3. Sigmoid Sinus
   a. Receives what sinus?
   b. Exits skull thru what foramen?
   c. BECOMES what VEIN?
4. What is the CONFLUENCE of SINUSES?
   a. Location?

Answer 52

1. a. Margin of Foramen Magnum (travels w/in Falx Cerebri along occipital bone)
   b. Vertebral Veins
   c. Left Transverse Sinus
2. a. It’s along the Tentorium by the Occipital and Petrous portion of temporal bone
   b. Sup Petrosal Sinus, Inf cerebral and Inf Cerebellar Veins
   c. SIGMOID SINUS
3. a. Inf Petrosal Sinus (Communicates w/Cavernous Sinus)
   b. Jugular Foramen
   c. Internal Jugular Vein
4. Meeting point for SAGGITAL, STRAIGHT, OCCIPITAL, and TRANSVERSE SINUSES
   a. Internal Occipital Protuberance of the Occipital Bone

Question 53

1. What are the 2 Fibrous Outer Layers of the Eye?
2. What are the 3 Vascular Inner Layers of the Eye?
3. What are the 2 Neural Layers of the Eye?
4. Avg Emmetropic Eye
   a. Axial Length?
   b. Horizontal Diameter?
   c. Vertical Diameter?

Answer 53

1. Cornea and Sclera
2. CB, Choroid and Iris
3. RPE and Retina
4. a. 24 mm
   b. 23.5 mm
   c. 23 mm

Question 54

Cornea: Good stuff to know

1. a. Tear Film n = ?
   b. Cornea n = ?
   c. Air/Tear Film provides how much Refractive power?
   d. Tear Film/Cornea interface gives how much refractive power?
   e. Cornea/Aq. Humor interface gives how much Refractive power?
2. Corneal Thickness
   a. Periphery
   b. Center
3. Corneal Curvature
   a. Central ROC for Ant Corneal Surface?
   b. Central ROC for Posterior Corneal Surface?
4. Diameters
   a. Anterior Vertical Diameter?
   b. Anterior Horizontal Diameter?
   c. Posterior Vertical Diameter?
   d. Posterior Horizontal Diameter?

Answer 54

1. a. 1.336
   b. 1.376
   c. ~44D
   d. ~5 D
   e. ~-6 D
2. a. 0.67 mm
   b. 0.55 mm
3. a. 7.8 mm
   b. 6.5 mm
4. a. 10.6 mm
   b. 11.7 mm
   c. 11.7 mm
   d. 11.7 mm

Question 55

Corneal Layers

1. Epithelium
   a. Junctions found here?
   b. Avg Thickness?
   c. What 3 cell types are found here?
2. Basement membrane: What Dz can occur here?
3. Bowman’s Layer: Avg Thickness?
4. Stroma: Thickness?
5. Descemet’s Membrane
   a. Avg Thickness
   b. What can form here?
6. Endothelium: thickness?
   a. Type of Junctions found here?
7. Avg Corneal Thickness?

Answer 55

1. a. Tight Junctions
   b. 52 um
   c. Surface, Wing and Basal Cells
2. EBMD (abnormal growth of BM)
3. 8-14 um
4. 450 um
5. a. 5-15 um
   b. Guttata (BM: FOCAL thickening of Descemet’s = Fuchs)
6. 5 um
   a. Leaky Junctions
7. 550 um

Question 56

Cornea: Epithelium (1)

1. Type of Epithelium?
2. Number of cell layers?
3. Surface Layer
   a. 2 Layers of what kind of cells?
   b. Plasma membrane in these cells secrete what?
   c. As Cells age, they’re sloughed off into what?
   d. What 2 things form a TIGHT BARRIER b/w Cells?
4. Wing Cells: Composed of how many cell layers?
   a. Joined to each other via what?
5. Basal Layer
   a. ONLY LAYER that does what?
   b. Secretes its own BM called what?
   c. BM attaches to the Basal Layer via what?
   d. BM also attaches to what layer? Via what?
   e. BM increases w/Age. By what age is the BM doubled in thickness in normal eyes?
6. What causes an RCE?

Answer 56

1. Stratified Squamous Non-Keratinized Epithelium
2. 5-6
3. a. Non-Keratinized Squamous cells
   b. Glycocalyx (also has microvilli and microplicae to increase SA)
   c. Tear Film
   d. Zonula Occludens and DESMOSOMES (Only cell layer w/in cornea to have Zonula Occludens!)
4. 2-3
   a. Desmosomes
5. a. that has MITOTIC ability
   b. Basal Lamina
   c. Hemidesomosomes (Anchors)
   d. Bowman’s Layer via Hemidesmosomes
   e. 60
6. Continual sloughing off (Hemidesmosomes are not attaching)

Question 57

Cornea: Epithelium (2)

1. BMs in the body have 2 layers
   a. Basal Lamina: Secreted by what?
   b. Reticular Lamina: Made by what?
2. What are 3 risk factors for RCEs?
3. Stem Cells
   a. Origin? (what is this and it’s size)?
   b. Stem cells become what kind of cells?
   c. Then these produce what kind of cells which migrate how?
4. A Lack of Stem Cells contribute to POOR CORNEAL EPITHELIAL MAINTENANCE in Peeps with what 3 problems?

Answer 57

1. a. Epithelial Cells
   b. Stromal Cells
2. a. Poor Hemidesmosome Attachments (Abrasions)
   b. EBMD
   c. Age-Related Thickening of BM (Getting old)
3. a. Palisades of Vogt (0.5-1.0 mm band around the LIMBUS)
   b. Basal Cells
   c. Wing Cells (migrate anteriorly to become the Surface Layer of the Epithelium)
4. a. ANIRIDIA
   b. STEVENS-JOHNSON SYNDROME
   c. ALKALI CORNEAL BURNS

Question 58

Cornea: Bowman’s Layer

1. Type of cells?
   a. Transition LAYER from Epithelium to what?
   b. Is it a BM?
   c. It’s made Prenatally by what?
   d. Is it a tough Layer?
   e. If damaged, can it regenerate?
   f. May play a role in maintaining what of the cornea?

Answer 58

1. Acellular; Random Type 1 Collagen Fibrils
   a. to Stroma
   b. NO!
   c. by Anterior Stromal Fibroblases
   d. YES
   e. NO
   f. The Correct Curvature

Question 59

Cornea: Bowman’s Layer (2): Dz

1. Band Keratopathy: What is it?
2. Pterygia: What do they do to Bowman’s Layer?
3. Crocodile Shagreen: What is it?
4. Reis-Buckler’s Dystrophy: What is it?
   a. Occurs Secondary to what?
5. Keratoconus: Initial Damage occurs in what layer?
   a. Advanced Keratoconus can result in HYDROPS due to damage to what layer?
6. Refractive Surgery
   a. LASIK Flap consists of what corneal layers?
   b. PRK: Application of Laser THROUGH BOWMANs LAYER causing what?

Answer 59

1. Calcium Deposits (Swiss-Cheese Pattern in Bowman’s Layer)
2. Destroy is as they progress onto the cornea
3. B/L Gray-White Polygonal Stromal Opacities that may involve Bowmans
4. Rare corneal epithelial dystrophy that shows early in life
   a. to damage to Bowmans
5. Bowman’s layer
   a. Descemet’s Membrane
6. a. Epithelium and Bowmans
   b. Post-op Corneal Haze

Question 60

Cornea: Stroma

1. Keratocytes: What are they and what do they do?
2. Collagen Fibrils
   a. Number of layers? (type of Collagen)
   b. Purpose
   c. Anterior 1/3 of the Stroma: More crosslinking b/w Collagen Fibers: Purpose?
   d. Posterior 2/3 of Stroma: More/Less organized than anterior 1/3 of Stroma? What does this cause?
3. Ground Substance
   a. Purpose?
   b. What’s in it?
   c. MAIN GAG in the CORNEA?

Answer 60

1. Fibroblasts; Make Collagen Fibrils and ECM
2. a. 200-300 (Type 1 Collagen) all UNIFORMLY SPACED
   b. Maintains Corneal Transparency
   c. Creates more rigidity and helps maintain corneal curvature

d. MORE organized, more uniformly spaced lamellae and larger w/less branches and less cross linking; –> More corneal Edema in Posterior Cornea (swelling more likely to occur here)

3. a. Filler b/w Collagen Fibrils and Keratocytes
   b. GAGs (water attracter)
   c. KERATIN SULFATE (66%)

Question 61

Cornea: Descemet’s Membrane

1. Produced by what?
2. Made of what kind of Collagen type?
3. Resistant to trauma and damage?
4. Can it regenerate after trauma?
5. Where does it terminate?
6. What does it become?

Answer 61

1. Corneal Endothelium
2. Type 4
3. YES
4. Maybe
5. at the Limbus
6. SCHWALBE’s LINE

Question 62

Cornea: Descemet’s Membrane: Dz

1. Hydrops: Due to what?
2. Haab’s Striae: What are they?
   a. Cause?
3. Hassall-Henle Bodies: What are they?
   a. Increase in number with age: Visual issues with them?

Answer 62

1. Rupture w/in Descemet’s Membrane in advanced Keratoconus
2. Folds in Descemet’s
   a. Congenital Glaucoma
3. Small areas of thickened Descemet’s in Corneal PERIPHERY (basically like guttata)
   a. None

Question 63

Cornea: Endothelium

1. Pumps found here? Purpose?
2. Endothelial cells have lots of what?
3. These cells are linked at APICAL BORDERS via what?
   a. Type of barrier formed?
4. Do they replicate?
   a. What happens if they get destroyed?
5. Loss of endothelial cells –> decrease in what? –> ?

Answer 63

1. Na/K/ATP-ase pumps; maintain corneal hydration and transparency
2. Organelles and Mitochondria that decrease w/age
3. Maculae Occludens
   a. Weak barrier (Lets AA, Glucose and nutrients in)
4. NO
   a. Pleomorphism and Polymegathism
5. Decrease in Na/K/ATPase Pump –> Stromal Edema

Question 64

Cornea: Blood supply

1. Vascular structure?
2. Main Nutrient source?
3. Lipids come mainly from what source?
4. What other source can provide nutrients?
5. Main Source of O2 w/EYES OPEN?
6. Main source of O2 w/EYES CLOSED?
7. Corneal Neo vessels arise from what cells? Response to what?

Answer 64

1. AVASCULAR
2. Aq. Humor
3. Limbal Conjunctival and Episcleral Capillary Networks
4. Palpebral Conjunctival Networks (Eyelids)
5. TEAR FILM
6. PALPEBRAL CONJUNCTIVAL BLOOD VESSELS
7. Endothelial cells of limbal capillary network; Cytokines and Growth Factors (VEGF included)

Question 65

Cornea: Innervation

1. 2 purposes?
2. CN that innervates cornea?
   a. Via what branches?
3. LPCNs and SPCNs form a myelinated network of 60-80 nerves that enter where in the cornea?
4. When do they lose their meylination?
5. What is NEUROTROPHIC KERATITIS?
   a. Due to damage to what?
6. 3 Networks of nerves formed
   a. Epithelium
   b. Anterior Stroma/Bowmans
   c. Midstroma

Answer 65

1. Pain Sensation and Proper Wound Healing
2. V1
   a. Long and Short Posterior Ciliary nerves that come from the NASOCILIARY NERVE
3. MID STROMA
4. after traveling 2-4 mm in the stroma, then they are “Naked” nerves called NOCICEPTORS…VERY SENSITIVE!
5. Poor corneal sensation and wound healing
   a. Secondary to damage to V1 (Herpes Simplex, Zoster, CVA, Diabetes)
6. a. Intraepithelial Plexus
   b. Subepithelial Plexus
   c. Stromal Plexus

Question 66

Conjunctiva

1. 4 Functions

Answer 66

1. a. Protection
   b. Movement w/o damaging soft tissues
   c. Antimocrobial and Immunological agents
   d. Produces Mucin

Question 67

Conjunctiva: 2 Layers

1. Stratified Non-Keratinized Epithelial Layer
   a. What 2 types of cells r in the Palpebral Conjunctiva
   b. Superficial cells have what 3 things?
2. Submucosa
   a. What is it?
   b. Outer Lymphoid Layer has what?
   c. Deep Fibrous Layer: has what?

Answer 67

1. a. Columnar/Cuboidal cells in Palpebral Conj —> Squamous cells in Bulbar Conj
   b. Melanin Granules, Microvilli, and Goblet Cells (number and density decreases closer to the limbus)
2. a. Loose CT that’s separated into 2 layers
   b. IgA, Macrophages, Mast cells, Lymphocytes, PMN Leukocytes, Eosinophils, and Langerhans Cells

c. Collagen Fibrils, Fibroblasts, BVs, Lymphatic Vessels, Nerves, Accessory Lacrimal Glands. Loosely attached to underlying structures.

Question 68

Conjunctiva: Palpebral Conjunctiva

1. Covers 3 things…What are they?
2. Marginal Conjunctiva
   a. Lines what?
   b. Composed of what cells?
   c. Submucosa is what here?
3. Tarsal Conjunctiva
   a. Lines what?
   b. Made up of what cells?
   c. Submucosa it what?
4. Fornical Conjunctiva
   a. Lines what?
   b. Deep fibrous layer has what in it?
   c. What attaches to the forniceal conjunctiva?

Answer 68

1. Eyelid Margin, Tarsal Plate, and Fornices
2. a. Eyelid margins
   b. Stratified Columnar Epithelial cells
   c. Very thin. Has a Deep fibrous layer
3. a. Tarsal Plates
   b. Stratified Columnar Epithelium
   c. Thicker than Marginal Conjunctiva submucosa. Has Lymphoid and a Deep fibrous layer with Accessory Lacrimal Glands. Strong adherence to Tarsal plate
4. a. Tarsal Plates
   b. Accessory lacrimal glands and Muller’s muscle (upper fornix)
   c. EOM Fascia. Moves conjunctiva in conjunction w/the eye to avoid compression of BVs and nerves w/in submucosa.

Question 69

Conjunctiva: Bulbar Conj.

1. Made up of what cells?
2. These cells become continuous with what?
3. Submucosa is loosely attached to what?
4. When does the Submucosa have a strong attachment?

Answer 69

1. Stratified Squamous Cells
2. with Corneal Epithelium at the limbus
3. to underlying Tenon’s capsule
4. until about 3 mm from the cornea when it fuses w/the end of Tenon’s Capsule, Episclera, and Sclera

Question 70

Conjunctiva: Limbus

1. What is it?
2. Purpose?
3. Limbal Epithelium has how many cell layers?
4. What 2 corneal layers end at the cornea?
5. What 3 things start at the limbus?

Answer 70

1. 1-2 mm zone around the cornea. Junction b/w Conj, Sclera, and Cornea
2. Nutrients for neighboring structures, Passage for Aq. Drainage w/in the eye; and limbus is supplied by blood from the capillary loops of the conjunctival and episcleral vessels.
3. 10 cell layers
4. Bowmans and Descemet’s Membrane (becomes Schwalbe’s Line)
5. Conjunctival Stroma, Episclera, and Tenon’s Capsule

Question 71

Conjunctiva:

1. Plica Semilunaris
   a. Cells type?
   b. It folds at what location?
   c. Purpose of folding?
   d. It’s also the floor for what?
2. Caruncle
   a. It’s a hybrid of Conjunctiva and Skin that has what 3 things?
   b. Location?
   c. Function?
   d. Likely a source for collection of what?

Answer 71

1. a. Stratified Squamous Bulbar Conjunctiva
   b. Medial Canthus
   c. Gives Slack in the Conjunctiva during LATERAL EYE MOVEMENTS
   d. for the Lacrimal Lake
2. a. Sebaceous Glands, Sweat Glands, and Goblet Cells
   b. on the Medial side of the Plica Semilunaris
   c. Unknown
   d. of Debris that’s seen in the healthy eye when waking up.

Question 72

Conjunctiva: Blood Supply

1. Palpebral Conjunctiva
   a. Including Marginal, Tarsal and Forniceal Conjunctiva, are all supplied by what 2 ARCADES?
2. Posterior Bulbar Conjunctiva
   a. Supplied by what arcades?
3. Anterior Bulbar Conjunctiva: Supplied by what Arcades?
4. Palpebral and Bulbar Conjunctiva are drained by what Veins?

Answer 72

1. a. Marginal and Peripheral Palpebral Arcades
2. a. Peripheral Palpebral Arcades
3. Anterior Ciliary Arteries
4. Anterior Ciliary Veins

Question 73

Conjunctiva

1. Conjunctival Lymphatics
   a. Lateral Lymph Vessels of bulbar and Palpebral conjunctiva drain into what Lymph Nodes?

b. Medial Lymphatic vessels drain into what lymph nodes?

2. Conjunctiva Sensory Innervation
   a. Bulbar conj is innervated by what nerves?
   b. Palpebral Conj innervated by what nerves?

Answer 73

1. a. Parotid Lymph nodes
   b. Submandibular Lymph Nodes
2. a. Long Posterior Ciliary Nerves (from Nasociliary Nerve of V1)
   b. V1 and V2 (Lacrimal, Infratrochlear and Supratrochlear nerves)

Question 74

Lens: Facts: KNOW!!

1. Avg Refractive Power?
2. Ant Lens ROC?
3. Post Lens ROC?
4. pH of Lens?
   a. of Aq. Humor?
   b. Of Blood Plasma?
5. Spherical or Aspherical?
   a. Gets flatter/steeper towards the periphery?
6. What attaches the posterior lens surface to the Anterior Vitreous?
   a. What’s the potential space b/w Posterior pole of lens and Ant. Vitreous w/in this ring called?
7. Peripheral Flattening and Gradient Index of Refraction in the lens help to reduce what?

Answer 74

1. ~20D (1/3 of total)
2. 8-14 um
3. 5-8 um
4. 6.9
   a. 7.6
   b. 7.4
5. Aspherical
   a. flatter
6. Ring-Shaped Hyaloid Capsular Ligament
   a. Retrolental Space of Berger
7. Spherical Aberration

Question 75

Composition of the Lens (1)

1. Lens Capsule
   a. What is it?
   b. Where’s it thinnest at?
   c. Where’s it Thickest at?
   d. Made up of what mostly?
   e. Barrier to what?
   f. Lens Zonules: Extend from what and enter the Anterior Capsule of the lens?

Answer 75

1. a. Transparent BM. (made by Anterior Lens Epithelium)
   b. Posterior Pole
   c. Anterior Pole of the lens (THICKEST BM in the body)
   d. Type 4 Collagen Fibers and GAGs
   e. to Large molecules (RBCs, WBCs, etc)
   f. From NPCE.

Question 76

Composition of the Lens (2)

1. Lens Epithelium
   a. Made up of what cells?
   b. Is there any posterior lens epithelium in the adult lens? Why?
   c. Lens epithelial cells are joined with what 2 things?
   d. This is the main site of what?
   e. Germinal ZONE (ant. to lens equator and is the Pre-Equatorial Region of the lens): Has what kind of cells? What do they become?

Answer 76

1. a. Single Layer of Cuboidal Epithelial Cells Adj. to anterior lens capsule
   b. NO. They become the Primary Lens fibers during embryological development

c. Maculae Occludens and Gap junctions
d. of Lens Metabolism

e. Mitotic Epithelial Cells; Secondary Lens Fibers (New lens fibers are made our whole life)

Question 77

Composition of the Lens (3): Lens Cortex

1. Lens Cortex
   a. % Water?
   b. % Protein?
   c. % other consituents?
   d. % of Lens Proteins that are Water Soluble alpha, Beta, and Gamma crystallins that are tightly packed w/in the Cytoplasm of Lens fiber cells?
2. UV exposure/oxidation –> Structural damage to lens fibers.
   a. Alpha Crystallins do what?
3. Index of Refraction in Nucleus? Why different here than the rest of the lens?

Answer 77

1. a. 65-70%
   b. 30-35%
   c. 1%
   d. 80-90%
2. a. Help beta and gamma crystallins recover from injuries. Prevents Degradation of lens fibers and loss of transparency
3. 1.41; Anterior Lens = 1.38; Aq and Vit Humor: 1.336; Different due to Different concentration levels of proteins throughout the lens.

Question 78

Lens: Lens Zonules

1. Lens is attached to what structure? via what?
2. Zonules are produced by the BM of what?
3. Zonules are made up of what?
4. Primary Lens Zonules: Attach directly to the lens capsule in what regions of the lens?
5. Secondary Lens Zonules connect primary lens zonules to what?
6. TENSION ZONULES connect primary lens zonules to what?

Answer 78

1. CB; LENS ZONULES
2. of NPCE in the Pars Plana and Pars Plicata
3. Microfibrils that contain fibrillin and ECM but NO TRUE ELASTIC FIBERS
4. Pre and Post Equatorial regions. (Rarely to the lens equator)
5. to each other or to the NPCE of the Pars Plana
6. to the Valleys b/w the Ciliary processes of the Pars Plicata

Question 79

Sclera

1. Mean ROC?
2. Thickest area at what location? (thickness)
3. Thinnest at? (thickness)
4. Weakest area?
5. Vascular/Avascular?
6. Minimally Innervated by what Nerves?

Answer 79

1. 11.5 mm
2. Posterior Pole (1.0mm)
3. Under the recti Tendon insertions (Clinically relevant during strab Sx to avoid inadvertent globe penetration). (0.30 mm)
4. Lamina Cribrosa (w/in ON)
5. Avascular (minimal blood from Episcleral, Choroidal vessels and LPCAs)
6. LPCNs and SPCNs

Question 80

Sclera: Episclera

1. Type of CT?
2. Inflammation of CB or iris will cause what to occur?
3. ANTERIOR CILIARY ARTERIES form networks where?

Answer 80

1. Loose CT w/a Capillary Network from Ant Ciliary Arteries
2. Dilation of Ant Ciliary Arteries –> Ciliary Flush (Circumlimbal redness)
3. in Anterior Conjunctiva and Episclera

Question 81

Sclera: Sclera Proper

1. Type of CT?
   a. Continuous with what?
2. IT’s made up of Irregular Collagen Bundles that provide what to the eye?
3. SCLERA CONTAINS LESS of what compared to Corneal Stroma?
4. Episclera is composed of what?
5. Sclera Proper is composed of what?

Answer 81

1. Thick, Dense Avascular CT
   a. w/Corneal Stroma
2. Strength; But NO Transparency
3. Less Fibroblasts and GAGs but similar Ground Substance
4. LOOSE CT and HIGHLY VASCULAR
5. DENSE CT and is pretty much AVASCULAR

Question 82

Sclera: Lamina Fusca

1. What is it?
   a. Contains what?
2. Why do infants usually have a BLUE TINT to their sclera?
   a. What Dzs can cause this BLUE TINT?
3. Old Peeps: Yellow Sclera: Why?

Answer 82

1. Innermost layer of sclera. Adj. To Choroid.
   a. Elastin Fibers and Lots of Melanocytes
2. Due to Uveal Pigmentation that’s seen thru their thinner sclera.
   a. OSTEOGENESIS IMPERFECTA or EHLER’s DANLOS SYNDROME
3. LIPIDS get trapped in Dense Irregular CT over time. OR it signifies a LIVER DZ!

Question 83

Sclera: Tenon’s Capsule

1. AKA?
2. What is it?
3. Starts where?
4. Extends to what?
5. It fuses with what 2 layers?
6. It’s Perforated posterior by what 4 things?
7. Name the layers of the eye: Ant to Post: REVIEW!

Answer 83

1. Fascia Bulbi
2. Thin, Transparent CT. Covers Episclera
3. 2 mm behind the limbus
4. Posteriorly to encircle the globe
5. Episclera and Conjunctival Submucosa layer
6. ON, Ciliary Vessels and Nerves, and Tendons of the 4 Recti Muscles
7. Conjunctival Epithelium, Conjunctival Stroma, TENON’s CAPSULE, Episclera, Sclera Proper, Lamina Fusca

Question 84

Sclera: Channels

1. Anterior Scleral Foramen: What is it?
2. Posterior Scleral Foramen: What is it?
3. Lamina Cribrosa: Weakest area of what?
4. What are EMISSARIA?

Answer 84

1. Space that the Cornea occupies (11.7 mm diameter)
2. Where the ON Enters…supported by LAMINA CRIBROSA
3. Of Sclera…most likely to be damaged with High IOP
4. Channels for Arteries, veins, and nerves heading to other ocular structures

Question 85

Sclera: Emissaria

1. Anterior Emissaria
   a. What Plexi?
   b. What Arteries?
   c. What Veins?
   d. What Nerves?
2. Middle Emissaria (Near equator): What passes thru?
3. Posterior Emissaria (Near the Optic Nerve): Channels for what Arteries and Nerves?

Answer 85

1. a. Deep and Intrascleral Venous Plexi (connnect w/Ciliary vein w/in CB)
   b. Anterior Ciliary Arteries (Ant Structures) and Episcleral Arteries (Thru sclera to Ant Chamber Angle)
   c. Aqueous Veins of Asher (Drain Aq. Humor from Schlemm’s Canal)
   d. LPCNs (Axenfeld’s Nerve loops): Inn to anterior eye structures
2. Vortex Veins (Drain choroid)
3. LPCAs, SPCAs, LPCNs, SPCNs (Suprachoroidal space)

Question 86

Anterior Chamber and Angle

1. Depth?
2. Diameter?
3. Amt of Fluid?
4. Avg IOP?
5. What are the boundaries of the AC?

Answer 86

1. 3.6 mm
2. 11-12 mm
3. 125 uL
4. 15.5 mmHg
5. Corneal Endothelium (Ant Boundary); Trabecular meshwork, Schlemm’s Canal, CB, Iris Root (Peripheral Boundaries); Anterior Iris Surface (Posterior Boundary)

Question 87

Structures w/in the Angle

1. Internal Scleral Sulcus: Found at what junction?
   a. Structures found here: Posterior to Anterior: I Can See The Stupid Line
2. Pilocarpine: Works on what meshwork?

Answer 87

1. Cornea-Sclera junction (Aq. Filtration site)
   (Iris, CB, SS, TM, Schlemm’s Canal, SL)
2. Corneal-Scleral Meshwork (Bad side effects: Contracts the CB –> Myopic Shift and Miotic Pupil)

Question 88

Angle

1. Becker-Shaffer System: Grades based on Most posterior structure of the angle that’s visible
   a. Grade 4
   b. 3
   c. 2
   d. 1
   e. Grade 0

Answer 88

1. a. CB
   b. SS
   c. 1/2 to 1/3 of TM
   d. Anterior Aspect of TM or SL
   e. No structures vidible

Question 89

Angle Structures

1. Scleral Spur: ANCHOR
   a. Origin site for what?
   b. This and the LAMINA CRIBROSA are the ONLY AREAS of the SCLERA that have what?
2. Trabecular Meshwork (TM)
   a. Major site for what?
   b. Shape?
   c. Which portion of the angle usually has the MOST amt of Pigment in the TM?

Answer 89

1. a. For Longitudinal Ciliary muscle fibers (Extends Posteriorly) and TM Lamellae (Extends anteriorly)
   b. ELASTIN
2. a. Aq. Humor Formation
   b. Triangular
   c. Inferior Portion of the angle

Question 90

Angle Structures: TM: 2 Divisions

1. Uveoscleral Meshwork
   a. What layers of the TM is it?
   b. Size of pores w/in this area?
   c. Endothelial Cells help in making what?
   d. What else does endothelial cells here contain?
   e. Does it USE SCHLEMM’s Canal for OUTFLOW?
   f. Major or Minor site for Aq. Filtration? (%)
   g. What decrease resistance in the Uveoscleral meshwork? How?
2. Corneoscleral Meshwork
   a. What layers of the TM is it?
   b. Pore size here?
   c. Do pores increase/decrease in size as it gets closest to Schlemm’s Canal and within the JUXTACANALICULAR TISSUE (JXT)
   d. JXT: AKA? What is it? What does it separate?
   e. JXT: Made up of 2 things?
   f. JXT: Does it have pores?
   g. How does Aq. Humor get thru the Tight junctions of the endothelium of Schlemm’s Canal?
3. Layers of TM: Inner Division to Outer Division (3)

Answer 90

1. a. Innermost 1-5 layers
   b. Large pores
   c. Protein
   d. Lysosomes for Phagocytosis of MELANIN and DEBRIS
   e. NO; Aq. Humor flows b/w Ciliary Muscle Fiber Bundles into the SUPRACHOROIDAL SPACE, then thru the Sclera OR thru Anterior ciliary veins, vortex veins, or other routes.
   f. Minor Site (unconventional Route: 5-35%)
   g. Prostaglandins; Relaxes Ciliary Muscle –> changes ECM –> Increase in Uveoscleral Outflow
2. a. Outer 8-15 layers of the TM…closer to Schlemm’s Canal
   b. Smaller
   c. Decrease
   d. CRIBRIFORM LAYER; Outermost Part of TM; Separates inner wall of Schlemm’s Canal from TM
   e. Endothelial cells and ECM
   f. NO! (Site of MOST RESISTANCE to Aq. Outflow)
   g. Thru a Pressure Gradient (High to low)…so IOP has to be GREATER than EPISCLERAL VENOUS PRESSURE
3. Uveoscleral Meshwork –> Corneoscleral Meshwork –> Juxtacanalicular Tissue

Question 91

Angle Structures: Schlemm’s Canal

1. Major site of what?
2. Where is it’s inner border located?
3. Outer border lies next to what?
4. Inner wall is lined by what kind of cells that come in contact with the JXT?
   a. What do these cells have in them? Purpose?
   b. Outer wall lined with what cells?
   c. What are INTERNAL COLLECTOR CHANNELS?
5. Aq Humor: Drains out of Schlemm’s Canal thru 2 Major routes:
   a. 1st Route: Short Efferents –> ?
   b. 2nd Route?
6. What does the Episcleral Venous Plexus drain into?
7. Schwalbe’s Line
   a. Tissue here?
   b. Represents the termination of what layer of the cornea?
   c. What Dz causes an Anteriorly Displaced Schwalbe’s Line?

Answer 91

1. Aq. Humor Filtration (90%)
2. by the SS and TM
3. Sclera near the limbus
4. Endothelial Cells
   a. Lots of Giant Vacuoles; transport Aq. Humor across the JXT into Schelmm’s Canal

b. Normal Endothelial Cells (No vacuoles) and Efferent vessels to drain Aq. Humor out of the eye.
c. Channels made of CT Septa; Increase SA for Aq. Filtration
5. a. –> Deep Scleral Venous Plexus –> Intrasclera Venous Plexus –> Episcleral Venous Plexus
b. External Collector Channels (Aq. Veins of Ascher) –> Episcleral Venous Plexus
6. the Anterior Ciliary Veins –> Muscular Veins –> Sup/Inf Ophthalmic Veins

7. a. Collagenous CT
   b. Descemet’s Membrane
   c. Posterior Embryotoxin

Question 92

Iris

1. Avg Width
2. Thickest where?
3. Thinnest Where? (Size)
4. Collarette
   a. What is it?
   b. Site of attachment for what during embryonic Development?
   c. Ciliary Zone: What is it?
   d. Pupillary Zone
   e. Crypts of Fuchs span into what zones?
5. Anterior Iris Stromal Leaf: Where is it found?
   a. what does it have in it?
6. Posterior Iris Stromal Leaf: Location?
   a. Contains most of what?
7. Aniridia:
   a. U/L or B/L?
   b. High association with what Dz? Why?
   c. Poor vision: Why?
   d. Other ocular issues?

Answer 92

1. 12 mm
2. COLLARETTE REGION
3. Iris Root (0.5 mm)
4. a. Circular Ridge ~1.5 mm from Pupillary margin.
   b. For Fetal Pupillary Membrane
   c. Iris Furrows. Lets iris tissue bunch towards periphery during dilation. (Radial streaks)
   d. Radial streaks present: smaller due to Iris BVs being smaller towards the pupillary margin
   e. Both and into the Collarette
5. Ciliary Zone of Iris
   a. Anterior Border Layer and small part of the iris stroma
6. Posterior to the Anterior Iris Stromal Leaf
   a. Most of the Iris stroma in the ciliary zone, and all of it in the Pupillary Zone
7. a. B/L
   b. Glaucoma (75%); PAS
   c. Foveal Hypoplasia w/Nystagmus
   d. Microcornea, Lens Subluxation, and ON Hypoplasia

Question 93

Iris Layers: Quick rundown:

1. Anterior Border Layer:
2. Stroma
3. Anterior Epithelium
4. Posterior Epithelium

Answer 93

1. Iris Color
2. Sphincter Muscle (Point where MACI becomes Non-Fenestrated)
3. Myoepithelial Cells and Dilator Muscle
4. Pupillary Ruff

Question 94

Layers of the Iris: Anterior Border Layer (1st)

1. Extends from pupil margin to what?
2. Cells?
3. Iris color due to amt of Melanin or number of melanocytes?
4. Blue Iris:
5. Brown Iris:
6. In Both Light and Dark Irises: Are both Epithelial Layers Heavily, or Lightly Pigmented?
   a. Condition where there is lack of pigment w/in these layers?
7. IRIS CRYPTS: What are they?
   a. Purpose?
8. Heterochromia: What is it?

Answer 94

1. to Iris Root
2. Fibroblasts, Melanocytes, Collagen Fibrils
3. Amt of Melanin
4. Little melanin, Thin anterior border layer
5. Lots of Melanin. Thick Anterior Border Layer
6. HEAVILY
   a. Oculocutaneous Albinism
7. Collagenous Columns in Ant Border Layer
   a. Passage for Aq. to enter Iris Stroma. (Give Iris Rough appearance)
8. Difference in Iris color b/w eyes: Congenital, or PROSTAGLANDIN USE, or Chronic inflammation

Question 95

Layers of the Iris: Iris Stroma (2nd)

1. What is it?
   a. Continuous with what?
2. Cells: What cells are found here?
3. Nerves?
   a. Sensory and Sympathetic Fibers are carried within what nerves?
   b. Parasympathetic Fibers are carried w/in what nerves?
4. BVs
   a. Iris Capillaries: Fenestrated or Non-Fenestrated?
5. What 3 things form the Blood-Aqueous Barrier?
6. MACI: Found in what?
   a. Formed by anastamoses b/w what 2 arteries?
7. Minor Arterial Circle of the Iris
   a. Found where?
   b. Formed by anastamoses b/w what arteries?
8. Radial Veins: Parallel what arteries?
   a. Where do they drain blood from?
9. Sphincter Muscle
   a. Type of muscle
   b. Anchored to what 2 things?
   c. Origin?
   d. Innervated by what CN?
   e. Parasympathetic Stimulation results in what?

Answer 95

1. Vascular, Loose collagen network w/less cells than the Anterior Border Layer
   a. Stroma of CB
2. Fibroblasts, Melanocytes, Lymphocytes, Macrophages, Mast Cells, Clump Cells (macrophages and detached epithelial cells)
3. LPCNs and SPCNs
   a. w/in LPCNs and SPCNs
   b. SPCNs
4. a. Non-Fenestrated
5. a. NPCE
   b. Iris BVs
   c. Endothelium SC
6. CB, close to the Iris Root
   a. ACAs and LPCAs
7. a. Iris stroma near pupillary margin
   b. of Radial Arteries (Branches off of MACI)
8. Radial Arteries
   a. Iris –> CB veins –> Choroidal Veins –> Vortex Veins –> Sup/Inf Ophthalmic Veins
9. a. Circular Sm. Muscle
   b. Iris Stroma and Dilator Muscle
   c. Anterior Iris Epithelial cells that detach and migrate into the iris stroma and become smooth muscle cells
   d. CN 3 Parasympathetic Fibers that travel with SPCNs
   e. Pupil Constriction

Question 96

Layers of the Iris: Anterior Epithelium and Dilator Muscle (3)

1. Anterior Iris Epithelium
   a. Next to what?
   b. Extends posteriorly to become what?
   c. What CELLS does it have?
   d. These cells eventually form what?
2. Dilator Muscle
   a. Extends RADIALLY from what?
   b. Terminates where?
   c. Sympathetic stimulation –> ?

Answer 96

1. a. Iris Stroma
   b. Pigmented Epithelium of the CB
   c. Pigmented MYOEPITHELIAL CELLS
   d. DILATOR MUSCLE
2. a. From the IRIS ROOT into the pupillary zone
   b. near the MIDPOINT of the IRIS SPHINCTER MUSCLE
   c. Dilation

Question 97

Layers of the Iris: Posterior Pigmented Iris Epithelium (4)

1. Type of cells?
2. Attached to what?
3. Become what as it extends posteriorly?
4. Pupillary Ruff: Formed by what?

Answer 97

1. Heavy pigmented Single layer of Columnar Cells
2. Pigmented Anterior Iris Epithelium
3. NPCBE
4. Posterior and Anterior Iris Epithelial Layers that curl Anteriorly towards the Anterior Border Layer of the Iris

Question 98

Iris: Dzs

1. PDS
   a. Cause?
   b. Pigment can accumulate on what?
   c. Can Cause what Dz in 50% of cases?
   d. Major SIGN?
2. Anterior and Posterior Pigmented Iris Epithelial Layers are attached how?
   a. What can develop if there’s a separation b/w the 2 epithelial layers?

Answer 98

1. a. Lens zonules rubbing on Pigmented iris epithelial layers
   b. Anterior Capsule, Iris surface, Corneal Endothelium, TM
   c. Glaucoma
   d. Krukenberg Spindle (Iris pigment in triangle form on iris)
2. Apex to Apex via Desmosomes and Microvilli
   a. IRIS CYSTS

Question 99

Posterior Chamber

1. What structures are around it?
2. Volume?
3. 3 Regions:
   a. Posterior Chamber Proper: Bound by what 4 things?
   b. Canal of Hannover (Circumlental Space): Located b/w what 2 things? What does it contain?
   c. Canal of Petit (Retrolental Space): Found b/w what 3 things?

Answer 99

1. Post surface of Iris, Ant face of the Vitreous, Equatorial region of the lens, CB
2. 0.060 mL
3. a. Posterior Iris Epithelium, Ciliary Processes, Anterior zonules and surface of the lens
   b. b/w Anterior and Posterior Lens Zonules over the equator of the lens; Equatorial Zonules
   c. Posterior lens zonules, anterior hyaloid membrane, and Posterior part of the CB

Question 100

Ciliary Body

1. Aq. Humor Production: By what?
2. Accommodation: Due to what nerves?

Answer 100

1. NPCBE

2. CN 3 Parasympathetic Fibers in the SPCNs from Ciliary Ganglion –> Ciliary muscle –> Contraction –> Accommodation

Question 101

Ciliary Body: Regions

1. Pars Plicata (Corona Ciliaris)
   a. What is it?
   b. Valleys of Kuhnt: What is it?
   c. What is found here?
2. Aq Humor flow?
3. Pars Plana (Orbicularis Ciliaris)
   a. What is it?
   b. Dentate Processes: What are they?
   c. Oral Bays: What are they?
   d. Dentate processes next to each other can join, making an ENCLOSED ORAL BAY: What does this get confused with?
4. Lens Zonules: Come from what?
   a. Made by what? Extend to what? Insert into what?
   b. If damaged, what happens?

Answer 101

1. a. Wide Anterior Part w/70-80 Ciliary Processes that extend into the Posterior Chamber
   b. Heavily Pigmented areas found b/w Ciliary Processes
   c. NPCBE: Does Production and Secretion of Aq. Humor
2. Pars Plicata –> Post Chamber –> Pupil –> Ant Chamber –> TM
3. a. Flatter, more posterior part. Starts at Pars Plicata, and extends to Ora Serrata.
   b. Extensions of Peripheral Retina (Ora Serrata) onto the CB (Pars Plana)
   c. Posterior Extensions of Pars Plana that lie b/w Dentate Processes
   d. RETINAL HOLES
4. Tertiary Vitreous from the BM of the NPCE in PARS PLANA and from valleys b/w ciliary processes in the Pars Plicata

a. Pars Plana; Valleys of Kuhnt; Lens Capsule
b. Lens Subluxation/Dislocation

Question 102

Layers of the CB (1): Supraciliaris

1. It’s a Potential Space filled with what?
2. It’s Continuous with what?
3. Fluid can accumulate in this potential space, causing what?

Answer 102

1. Loose CT w/lots of Collagen Bands
2. the Suprachoroid at the Ora Serrata
3. a Ciliary Body Detachment

Question 103

Layers of the CB (2): Ciliary Muscle

1. Innervation?
2. Smooth muscle: Does what?
3. Anchored to what anteriorly? Posteriorly?
4. 3 Types of Fibers
   a. Longitudinal Muscle Fibers (of Brucke): Muscle bundles form what shape? Extend into what as what?

b. Radial Fibers: Shape? Origin? Terminate where?
c. Muller’s Annular Muscle: Muscle shape? Location? Origin?
d. Which muscle is the largest?

5. Ciliary Stroma
   a. Location? (B/w what 2 things?)
   b. Has what?
6. MACI
   a. Location?
   b. Capillary type? Location?
   c. What regulates release of large substances from the capillaries?
7. The rest of the BVs w/in Ciliary stroma (Outside of the ciliary processes) have what kind of capillaries?
8. Aq. Humor: Made from PLASMA that comes from where?

Answer 103

1. CN 3 PS Fibers and a few Sympathetic Fibers
2. Accommodation
3. SCLERAL SPUR; STROMA of the CHOROID
4. a. V-Shape; Origin: SS and TM; Extend: Choroid as MUSCLE STARS (stellate-shaped terminations)
   b. V-Shape; SS; Insert: CT by base of Ciliary Processes
   c. Circular muscle bundles; SMALLEST; Most medial CM fibers and near MACI; Origin: SS. Works like Sphincter muscle
   d. Longitudinal muscle fibers
5. a. CM and Epithelial layers
   b. MACI; Vascularized
6. a. Inward from CM, near Iris Root
   b. Large, fenestrated capillaries; Ciliary epithlium of Pars Plicata
   c. Tight zonular junctions of NPCE
7. Non-Fenestrated Capillaries
8. From Fenestrated capillaries of MACI

Question 104

Layers of the CB (3): Ciliary Epithelium

1. Helps make what?
2. Pigmented CE
   a. Cells?
   b. Anteriorly: Continuous with what?
   c. Posteriorly: Continuous with what?
3. NPCE
   a. Inner cells?
   b. What comes from the Pars Plana and Pars Plicata?
   c. Anteriorly: Continuous with what?
   d. Posteriorly: Continuous with what?

Answer 104

1. Blood-Aqueous Barrier; Lines CB
2. a. Outer Cuboidal Epithelial Layer attached to ciliary stroma thru Basal Lamina (BM). Lines CB
   b. Pigmented Anterior Iris Epithelium and BM
   c. RPE and Inner BM of Bruch’s Membrane
3. a. Inner cuboidal/columnar epithelial layer lines posterior chamber
   b. Lens Zonules
   c. Pigmented Posterior Iris Epithelium and its Basal lamina
   d. Ora Serrata which then becomes Neural Retina. Basal Lamina continuous w/ILM of retina.

Question 105

Blood Supply of CB:

1. What 2 arteries?
2. Veins in CB drain thru what?

Answer 105

1. LPCAs and MACI

2. Vortex Veins

Question 106

Innervation of CB

1. CN 3: What purpose?
2. Sympathetic Nerve Fibers: From what ganglion?
   a. They travel with what nerves?
3. Sensory Nerve Fibers: From what ganglion?
   a. Travel with what nerves to CB?

Answer 106

1. PSNF travel w/SPCNs from CILIARY GANGLION to supply Ciliary Muscle for Accommodation
2. Superior Cervical Ganglion
   a. LPCNs and SPCNs –> Inn ARTERIES in CB
3. Semilunar Ganglion of V1
   a. LPCNs to CB

Question 107

Choroid

1. Thickest where (thickness)?
2. Thinnest where? (Thickness)?

Answer 107

1. Posterior Pole (0.2 mm)

2. Ora Serrata (0.1 mm)

Question 108

Layers of the Choroid (1): Suprachoroid (Lamina Fusca)

1. What is it?
2. Made up of what?
3. It’s a passage for what Arteries/Nerves
4. LPCNs extend from what?
5. This layer has parts from what 2 layers?

Answer 108

1. Potential space b/w sclera and choroid vessels
2. Loosely packed collagen fibers, Fibroblasts, melanocytes and ECM
3. LPCAs and LPCNs
4. from Mid-Equatorial region to Ora Serrata along 3 and 9 o’clock meridians
5. Choroid and Sclera

Question 109

Layers of the Choroid: Choroidal Stroma (2)

1. Made up of what?
2. Innervation of vessels?
3. Amt of BVs and Melanin granules?
   a. Potential for what Dz to occur?
4. SPCAs: 2 Separate layers w/in Ciliary Stroma
   a. Haller’s Layer: Location and type of Vessel size?
   b. Sattler’s Layer: Location and type of vessel size?

Answer 109

1. Loose CT w/Choroidal BVs, nerves, and melanin
2. Sympathetic NS –> Vasoconstriction
3. TONS!
   a. Choroidal Melanomas (MOST Common Primary Intraocular Tumor in Adults)
4. a. Posterior layer; LARGE VESSELS…branch to Sattler’s layer. Part of VORTEX VEINS are here.
   b. Anterior Layer; SMALLER VESSELS…make Capillary Bed. Veins that drain from here are LARGE VORTEX VEINS (they have NO VALVES!!)

Question 110

Layers of the Choroid: Choriocapillaris (3)

1. Made up of what?
2. Highest concentration found where in the Retina?
3. Nourishment to what layers of the retina?
4. Number of Pericytes (Lots or little)?

Answer 110

1. Large Fenestrated Capillaries
2. At the MACULA
3. Outer layers
4. Few. Regulate BF.

Question 111

Layers of the Choroid: Bruch’s Membrane (Basal Lamina)

1. Thickness?
2. Goes from ON to what structure?
3. What are the 5 LAYERS?

Answer 111

1. Thin (2 um)…innermost layer of the CHOROID
2. to CB
3. a. BM of Choriocapillaris
   b. Outer Collagenous Layer
   c. Elastic Layer (ANGIOD STREAKS OCCUR HERE: 50% IDIOPATHIC)
   d. Inner Collagenous Layer
   e. BM of RPE

*Drusen accumulates b/w ICL and BM of RPE

Question 112

Facts about Bruch’s Membrane: PASSAGE of NUTRIENTS AND WASTE

1. Nutrients Pass from what to what?
2. Waste Products: From what to what?
3. Phospholipids: Accumulate on what with age?
   a. What do they cause?
   b. Inhibit what?
4. What are Drusen?
   a. What causes them?
5. CNVMs (Choroidal Neovascular Membranes)
   a. Occur due to what?
   b. Occur in what conditions?
6. ANGIOD STREAKS
   a. Damage to what layer of Bruch’s?
   b. REMEMBER this: PEPSI

Answer 112

1. Choriocapillaris –> Bruch’s –> Retina
2. Retina –> Bruch’s –> Choriocapillaris
3. Bruch’s
   a. Makes it Hydrophobic and slows water movement
   b. Inhibits transport of metabolites
4. Waste from Retina b/w ICL and BM of RPE.
   a. Lack of nutrition supply to retina…big finding w/ARMD
5. a. Break in Bruch’s Membrane
   b. Exudative ARMD, Pathological Myopia, Histoplasmosis, Choroidal rupture, and Pseudoxanthoma Elasticum (Associated with ANGIOD STREAKS)
6. a. Elastic Layer
   b. Pseudoxanthoma Elasticum, Ehlers-Danlos Syndrome, Paget’s Dz, Sickle Cell Dz, Idiopathic

Question 113

Blood and Nerve Supply to Choroid

1. Arteries: Anterior Choroid?
2. Arteries: Form choriocapillaris and give blood to Posterior Choroid?
3. What drains the Choroid?
4. LPCNs/SPCNs: Carry what nerves to innervate the choroid?
   a. Sympathetic Fibers from what?
   b. CN 7 PSF from what ganglion; Inn what?
   c. CN 3 PSF from what ganglion: Inn what?
   d. CN V1 Sends what info to the Choroid?

Answer 113

1. LPCAs
2. Branches of SPCAs
3. VORTEX VEINS
4. Parasympathetic, Sympathetic, and Sensory Fibers
   a. Sup Cervical Ganglion…Vasoconstrict Choroidal Vessels

b. Pterygopalatine Ganglion; Vasodilate Choroidal Vessels
c. Ciliary Ganglion; Unknown function
d. Sensory innervation to choroid

Question 114

Vitreous Chamber

1. Volume?
2. Shape?

Answer 114

1. 4 mL (80% of volume of eye)

2. Spherical except it has a Concave shape Anteriorly due to LENS (Called the PATELLAR FOSSA)

Question 115

Vitreous Chamber: Contents

1. % Water?
2. Type of Collagen and what GAG?
3. When is the vitreous evenly liquid and gel (50/50)
4. Most changes in Collagen/HA complex happen in what part of the vitreous?
5. Predominate CELL TYPE in Vitreous? LOCATION?
   a. What do they do?
6. Where are Fibroblasts located? Purpose?
7. Cause of Floaters?
   a. Cause of PVD?

Answer 115

1. 98.5-99.7% H20
2. Type 2; Hyaluronic Acid
3. at age 70-80
4. Central Vitreous
5. HYALOCYTES; w/in VITREOUS CORTEX
   a. Make HA
6. Vitreous Base; Make Collagen Fibrils
7. HA/Collagen complex is disrupted and Collagen clumps up in bundles.
   a. This collagen can contract, causing posterior hyaloid membrane to detach from retina…WEISS RING is the sign.

Question 116

Regions of the Vitreous: Vitreous Cortex

1. What’s in it?
2. What divides the cortex into Anterior and Posterior Hyaloid Regions?
3. Anterior Hyaloid
   a. Extends from Vitreous base to lens
   b. Patellar Fossa: What is it?
   c. Hyaloideocapsular Ligament of Weiger: What is it?
   d. Berger’s Space: What is it?
4. Posterior Hyaloid: Location?

Answer 116

1. High density gel w/Collagen Fibrils, Cells, Proteins, and Mucopolysaccharide Filler substance.
2. the VITREOUS BASE
3. b. Depression (concave) in anterior vitreous due to Posterior lens.
   c. Strong circular adhesions b/w Anterior Vitreous, Posterior Zonules, and Posterior Capsule of the lens
   d. Potential Space b/w Anterior Hyaloid and Posterior Lens Capsule
4. Vitreous Base –> Optic Disc

Question 117

Regions of the Vitreous: Cloquet’s Canal (Hyaloid Channel or Retrolental Tract)

1. What is it?
   a. What’s in it?
   b. Former site of what?
   c. What happens after development?
   d. Posterior end of Cloquet’s Canal by the Optic Disc is called what?
2. Epicapsular Star: Location?
   a. What is it?
3. Mittendorf’s Dot: Remnant of what?
   a. Location?
4. Bergmeister’s Papillae
   a. What is it?
   b. Location?

Answer 117

1. Remnant of the Primary vitreous
   a. Low density liquid surrounded by high density gel vitreous.
   b. HYALOID ARTERY that nourished the lens during development
   c. The artery regresses to the optic disc…becomes the CRA
   d. Area of Martegiani
2. Anterior Lens Capsule
   a. remnant of the connection b/w anterior tunica vasculosa lentis and Posterior Hyaloid artery
3. Hyaloid Artery
   a. Posterior Lens Capsule
4. a. Remnant of Hyaloid Artery
   b. Optic Disc

Question 118

Retina: RPE

1. Single layer of what cells?
2. Apical side faces what?
3. Basal Side is adjacent to what?
4. BM of RPE STRONGLY ADHERES to what?
   a. What does this form?
5. What is the RPE derived from?
6. Microvilli are found on RPE: What do they do?
7. What is found in the Subretinal Space (potential space) b/w RPE microvilli, PR outer segments?
8. Subretinal Space b/w RPE and Neural Retina can lead to the development of what?

Answer 118

1. Cuboidal Pigmented Cells
2. Retina
3. Bruch’s Membrane
4. CHOROID
   a. inner portion of Bruch’s Membrane
5. Outer Layer of the Optic Cup
6. PHAGOCYTOSIS of Photoreceptor Outer Segments
7. Interphotoreceptor Matrix
8. RETINAL DETACHMENTS (Weak attachment)

Question 119

Retina: RPE (2) Functions

1. Phagocytosis of PR Outer segments: What can develop if their is undigested material from PR outer segments that accumulate in the RPE?
   a. What are found w/in the RPE cells?
2. Transfer Ions, Water, and Metabolites:
   a. What pump moves LACTATE from RPE to the Choroid?
   b. What pump moves GLUCOSE from choroid to RPE?
3. What Vitamin is stored and metabolized by RPE Cells?
4. Blood-Retinal Barrier: Tightly linked RPE cells by what?
5. Absorbs Light: How?
6. Produces Growth Factors for Tissue Maintenance: What do they produce?

Answer 119

1. LIPOSFUSCIN (PR outer segments that don’t get digested) can contribute to RPE cell death.
   a. LYSOSOMES
2. a. Proton-Lactate-Water Cotransporter
   b. Glucose Transporter
3. VITAMIN A (Trans-Retinol)
4. A TERMINAL COMPLEX (zonulae occludens, Zondulae adherens, and Maculae adherens)
5. RPE has Pigment Granules that absorb light that isn’t absorbed by rods and cones
6. VEGF (needed for Choriocapillaris Function), PEDF (pigment epithelial derived factor) which is Antiangiogenic that counterbalances the effects of VEGF.

Question 120

Photoreceptor Layer

1. Number of Rods per eye?
2. Number of Cones per eye?

Photoreceptors

3. Inner Segment: What does it make?
   a. MYOID: What is it?
   b. ELLIPSOID: What is it?
   c. CILIUM: Purpose?

• Think: “M”yoid: MAKES Protein
• Think: “E”llipsoid: ENERGY

Answer 120

1. 120 million
2. 6-8 million
3. PHOTOPIGMENTS. Sent to Outer Segment. Becomes part of the discs.

a. Inner layer of inner segment. Has ER and Golgi…Protein Synthesis
b. Outer layer of inner segment. TONS of MITOCHONDRIA
c. Connector b/w Inner and Outer Segments

Question 121

Photoreceptor Layer: Outer Segment

1. What does it have?
2. What does it Produce? How many per rod? Per Cone?
3. Describe the Life Cycle of Disc Photopigments.

Answer 121

1. Tons of Membranous Discs w/Photopigments made in Inner Segments
2. DISCS that surround photopigment molecules; 600-1000 discs per rod; 1000-2000 discs per cone
3. made in Inner Segment then incorporated into Discs at BASE of OUTER SEGMENT, then shed at the tip of the OUTER Segment for Phagocytosis by RPE.

Question 122

Photoreceptor Layer: RODS

1. Vision type?
2. Rod Density is GREATEST WHERE?
   a. What is this area called?
3. Rods terminate in what?

CONES:

4. Vision?
5. Cones have 3 types of photopigments that each contain what?
   a. Name the 3 types of photopigments and what photon light they absorb.
6. Location of Fovea from the Optic Nerve?

Answer 122

1. Scotopic
2. 5 mm (20 degrees) from the fovea
   a. ROD RING
3. in Spherules (Cones terminate in PEDICLES)
4. PHOTOPIC
5. Same CHROMOPHORE (11-cis Retinal) but differ in Protein (OPSIN) component
   a. Cyanolabe (Blue): Max absorption at 440 nm
   b. Chlorolabe (Green): Max at 535 nm
   c. Erythrolabe (Red): Max at 565 nm
6. 5 mm Temporal and 0.4 mm inferior to the center of the optic nerve. (Sup and Nasal to ONH if seen w/78D or 90D)

Question 123

ELM

1. What is it?
   a. Purpose is to act as a barrier against what?

ONL:
2. Contains what?

Answer 123

1. Barrier. No Cells. Made of a Band of DESMOSOMAL ATTACHMENTS b/w Muller Cells and Inner segments of Photoreceptors.
   a. Against Large Metabolites!
2. a. Cell Bodies of RODS and CONES

Question 124

OPL:

1. Location of what?
   a. What’s the purpose of spherules and pedicles?
2. Rod Spherule: How many synapses can it make with ROD BIPOLAR Cell Dendrites?
   a. What else can connect to them?
   b. Can connect to what type of bipolar cells?
3. Cone Pedicle:
   a. Size compared to Rod Spherule?
   b. Can form a Synaptic Triad that consists of what?
   c. Cone Pedicles can connect with what type of Bipolar Cells?

Answer 124

1. Synapses b/w Rods, Cones, and Bipolar and Horizontal Cells
   a. Synaptic Terminals for Rods and Cones…connect w/Bipolar and Horizontal Cells
   b. ONLY to ROD BIPOLAR CELLS
2. a. Larger
   b. 3 Horizontal cell dendrites or 2 horizontal cell dendrites on either side of 1 bipolar cell dendrite.
   c. Midget, Flat, or Diffuse Flat Bipolar Cells

Question 125

OPL

1. Site of what?
2. What is the OPL called w/in the MACULA?
3. It’s the only RETINAL Layer to GET BLOOD SUPPLY FROM WHAT?
4. What does the CRA supply?
5. What describes a Splitting of the OPL?
6. What Dz is located in the OPL?

Answer 125

1. 1st Synapse w/in the Visual Pathway
2. Henle’s Fiber Layer
3. Choroid AND Retina (CRA)
4. Inner 2/3 of Retina (NFL, GCL, IPL, INL, and part of the OPL)
5. RETINOSCHISIS
6. HARD EXUDATES

Question 126

INL

1. Cell bodies of what? (5)
2. Bipolar Cells
   a. Rod Bipolar: Connect with?
   b. Midget Bipolar: Connect with?
   c. Flat Bipolar: Connect with?
   d. Diffuse Flat Bipolar: Connect with?
3. Horizontal Cells
   a. Location?
   b. Modify info going to Bipolar cells via what?
   c. Type of Inhibition?
4. Interplexiform Cells: Purpose?
5. Amacrine Cells: Purpose?
6. Muller Cells: Most common what?
   a. Purpose?
7. What 2 cells do Inhibitory feedback needed to fine-tune a retinal signal?

Answer 126

1. Bipolar, Horizontal, Interplexiform, Amacrine, and Muller Cells
2. a. Rod Photoreceptors
   b. 1 Cone and 1 Ganglion cell (Fine details…Fovea)
   c. Several Cone Photoreceptors
   d. More cone photoreceptors than Flat Bipolar
3. a. OPL (Connect to {Photoreceptors, Bipolar and Horizontal Cells)
   b. LATERAL INHIBITION
   c. Inhibitory Feedback (Photoreceptors) and Inhibitory Feed-Forward (Bipolar Cells)
4. Carries vertical info b/w OPL and IPL
5. Lateral info…to Bipolar, Interplexiform, Ganglion, and Amacrine
6. GLIAL CELLS in RETINA
   a. Structure and support (ILM to ELM)
7. Amacrine and Horizontal Cells

Question 127

IPL

1. Location of synapse b/w what?
2. AMACRINE Cells do what?
3. Bipolar Cell Synapse?
4. Amacrine Cell Synapse?

Answer 127

1. 2nd Order (Bipolar) and 3rd Order (Ganglion cell) neurons.
2. Modify synapse b/w Bipolar and Ganglion cells.
3. 1 process from Amacrine and 1 dendrite from Ganglion
4. Bipolar, Ganglion, Interplexiform, and Amacrine cells w/in IPL

Question 128

GCL

1. Each Ganglion has 1 axon…that travels in ON and terminated where?
2. Ganglion cells in Foveola?
3. P-Cells: Sensitive to what?
   a. P1: AKA?
   b. P2?
4. M-Cells: Size and purpose?

Answer 128

1. LGN or at Superior Colliculus or Pretectal Nucleus
2. NONE in foveola, 4-7 GC layers in Macula, 1-2 GCLs in the rest of the retina.
3. Small Diameter Axons…Sensitive to COLOR and FINE DETAIL, More common than M-Cels
   a. Midget Ganglion Cells; Most common; 1 dendrite only synapses w/1 Midget Bipolar…connects w/1 cone w/in Fovea.

b. Larger than P1…Multiple dendrites synapse w/many bipolar cells
4. Large diameter axons. Sensitive: DIM LIGHT and MOTION

Question 129

NFL

1. Found in Fovea?
2. Thickest where on the Optic Disc Margin?
3. Papillomacular Bundle: NFL Fibers from what?

Answer 129

1. NO! (why u wont see a CWS there!). Starts w/in Parafoveal region and is known as Henle’s Fiber Layer
2. Sup and Inf Margin
3. From Macula…insert on Temporal Margin

Question 130

NFL: Abnormal Findings

1. AKA: SOFT EXUDATES? Most commonly caused by what?
2. AKA: Drance Hemes? Location?
3. Type of Hemes associated with Retinal Vascular Pathology? (Examples?)
4. What are Dot Blot Hemes associated with?

Answer 130

1. CWS; DIABETES
2. SPLINTER HEMES; w/in NFL at or near optic Disc
3. Flame Hemes; Diabetes, HTM, Vein Occlusions
4. DEEP Retinal issues w/in the INL!

Question 131

ILM

1. Made up of what?
2. What replaces Footplates of Muller Cells at the OPTIC DISC (So no ILM here)?

3, Only Dz that AFFECTS the ILM?

4. Neural Messaging…?

Answer 131

1. Footplates of Muller Cells and Basal Lamina bound to Vit Humor Collagen Fibrils
2. ASTROCYTES
3. EPIRETINAL MEMBRANES
4. 128 million Photoreceptors –> 35 million Bipolar Cells –> 1.5 Million Ganglion Cells

Question 132

Neuroglial Cells = 2x4’s (support only)

1. Muller Cells: Most common Glial cell; Only found in Retina. Extends from what to what?
   a. Most of their cell bodies found where?
2. How can Muller Cells give Structural and Nutritional Support to the Retina? (4 ways)
3. Main source of energy to the retina?
4. Astrocytes: Purpose?
5. Microglial Cells: Purpose?

Answer 132

1. ELM to ILM
   a. INL
2. a. Maintain alignment of other neurons
   b. Give nutrients to retina and aid in GLYCOGEN METABOLISM
   c. Act as a BUFFER to regulate electrolyte concentration w/in extracellular space (Esp of K+)
   d. Absorb and Recycle Metabolic Waste Products (GABA and Glutamate)
3. Glucose via ANAEROBIC GLYCOLYSIS! (Excess glucose stored in Muller cells as glycogen)
4. Help make the ILM at the OPTIC DISC; Similar functions as the Muller Cells
5. Phagocytic Cells…anywhere in retina.

Question 133

Retinal Blood Supply

1. Outer 5 Retinal Layers?
2. Inner 2/3s?
3. OPL?
4. CRA:
   a. 2 Capillary networks?
5. What supplies the Macula?
   a. What artery is found in 15-20% of the Population and lets the macula be spared in a CRAO?
6. Vein: Drains inner layers?
7. Vein: Drains outer layers of the retina?
8. Why do almost ALL BRVOs occur at AV crossings?

Answer 133

1. Choroid
2. CRA
3. Gets both
4. a. Superficial (NFL) and Deep (INL)
5. SPCAs from Choriocapillaris
   a. CILIORETINAL ARTERY
6. Central Retinal Vein
7. Vortex Veins
8. because retinal arteries and veins share a common adventitia at these crossings, so when arterial walls are damaged, it causes venous wall compression and thrombus formation.

Question 134

Macula

1. Diameter?
2. Subtends what angle?
3. Location from Lateral edge of Optic Disc?
4. Contains 2 MAJOR Xanthophyll pigments?
   a. Purpose?
5. Name from the center of the macula, to the outermost part of the macula?

Answer 134

1. 5.5 mm
2. 18 degress
3. 3.5 mm lateral and 1 mm inf
4. Zeaxanthin and Lutein
   a. Reduce CAs and protect against free radicals
   b. Usually found in inner segments of photoreceptors
5. Foveola–> Fovea –> Parafovea (0.5mm) –> Perifovea (1.5mm)
   * From foveala to edge of fovea: 0.75 mm **Radii

Question 135

Macula (2)

1. Fovea
   a. Diameter?
   b. What part of the fovea is avascular?
   c. Blood supply by what?

1A: Foveola

a. Diameter?
b. Thickness?
c. What region is the thickest of the retina? Why?
d. WHAT CONES are NOT FOUND in the CENTRAL 1 DEGREE of the FOVEOLA?
e. What 6 Layers are found here? (RPE OO I)

2. Henle’s Fiber Layer: What is it?

Answer 135

1. a. 1.5 mm (~1 DD)
   b. 0.4-0.5 mm (minimize light scatter)
   c. By underlying Choriocapillaris via SPCAs

1A:a. .35 mm

b. 0.13 mm (THINNEST)
c. Parafovea d/t lateral displacement of retinal cells away from the foveola.
d. NO BLUE CONES or RODS
e. RPE, Photoreceptor layer, ELM, ONL, OPL (Henle’s Fiber Layer), and ILM

2. OPL w/in the Macula. Has AXONS of PHOTORECEPTORS; No Bipolar/Ganglion Cells w/in Fovea or Foveala (so no INL, IPL, GCL, or NFL)

Question 136

Macula (3)

1. Parafovea
   a. Radius/Diameter?
   b. What’s the CLIVUS?
   c. Retinal Layers found here?
   d. How thick is it?
2. Perifovea
   a. Diameter?
   b. Boundary b/w Perifovea and Parafovea: How thick?
   c. Boundary b/w Perifovea and Periphery?
3. Rod density starts to increase where?
   a. Densest where?

Answer 136

1. a. 0.5mm/1.0 mm
   b. Boundary b/w Parafovea and Fovea….Sloping of retinal layers w/in macula
   c. ALL
   d. THICKEST (7-11 layers of bipolar cells as well as Ganglion cells)
2. a. 3.0 mm
   b. 4 cell layers thick of Ganglion cells
   c. 1 cell layer thick
3. 1.2-1.7 mm from center of fovea (w/in parafovea and perifovea regions)
   a. 5 mm from center of the fovea (ROD RING)

Question 137

Peripheral Retina

1. Terminates where?
2. What is the Ora Serrata?
   a. What are Dentate Processes?
   b. What are Oral Bays?
3. What does the RPE become?
4. What happens to the Neural Retina

Answer 137

1. 5 mm anterior to the equator of the eye at the ORA SERRATA
2. 2 mm band at anterior most portion of the retina, made up of Dentate Processes and Oral Bays
   a. Extensions of PEripheral retina onto PARS PLANA of CB
   b. Extensions of Pars Plana into the PERIPHERAL RETINA
3. Pigmented Ciliary Epithelium
4. Thins and transitions into NPCE

Question 138

CNs

1. CN10 Palsy: What happens with the Uvula?
2. CN12 Palsy: Tongue deviates to what?

Answer 138

1. Deviates away from lesion (C/L) and DOES NOT ELEVATE

2. Toward Lesion (I/L)

Question 139

CN2

1. Motor/Sensory?
2. Axons of GCs converge at optic disc and exit the Sclera at what?
3. CN2 Fibers go to 1 of three destinations and what does each do?

Answer 139

1. Sensory
2. Lamina Cribrosa
3. a. LGN: relays info to Primary Visual Cortex (V1)
   b. Pretectal Nucleus: Pupil Innervation
   c. Superior Colliculus: Control of Saccades

Question 140

CN3

1. Where are the nuclei located?
2. Purpose?
3. CN 3 Nuclei are connected to the nuclei of which CNs and through what?
   a. They also receive information from what 2 places?
4. Fibers leaving MR, IR, and IO project to which nucleus?
5. Fibers leaving SR project to which nucleus?
6. What controls the Levator Palpebrae Muscle for each eye?
7. A Lesion to the Levator Palpebrae Subnucleus will CAUSE WHAT SIGN?
8. Describe the pathway of the fibers.
9. Sup Division Innervates what?
10. Inf Division Innervates what?

Answer 140

1. Midbrain: Superior Colliculus
2. Voluntary Motor: SR, MR, IR, IO, and EW Nucleus (Parasympathetic Innervation) to Ciliary and Iris Sphincter Muscles via the Ciliary Ganglion
3. 4, 6, 8 via MLF.
   a. Superior Colliculus and Visual Cortex
4. Ipsilateral Nucleus
5. C/L Nucleus
6. 1 CENTRAL SUBNUCLEUS
7. BILATERAL PTOSIS
8. Sub-nuclei Fibers Join –> Exit Brainstem –> Travel next to the PCA –> Enter Cavernous Sinus –> CN3 receives Sympathetic Fibers from Internal Carotid Artery Plexus –> Division of CN 3 to Sup and Inf Divisions –> Enters Orbit via Sup Orbital Fissure
9. SR and Sup Levator Palpebrae Muscle; Symp Fibers to Muller’s Muscle of Upper Eyelid
10. MR, IR, IO, Sphincter muscle, Ciliary Muscle; Parasymp Fibers from EW nucleus –> Ciliary Ganglion –> become SPCNs –> inn sphincter and ciliary muscle for Pupil Constriction and Accommodation respectively

Question 141

CN 3: Damage…

1. Pupillary Fibers…where are they located in regards to CN3?
2. A CN3 PALSY that’s PUPIL INVOLVING (Fixed and dilated pupil): Where do we suspect the problem to be?
3. Pupil Sparing CN3 Palsy most likely due to what?

Answer 141

1. On the OUTSIDE of all other fibers w/in CN3.
2. Aneurysm of the PCA! (at the junction b/w PCA and ICA)
3. ISCHEMIA of Small BVs that nourish inner fibers of CN3…usually d/t Diabetes or HTN.

Question 142

CN 4

1. Length?
2. Number of nuclei and location?
3. How does CN 4 connect to the Visual Cortex?
4. This is the ONLY CN to do what?
5. In a Sup Oblique Palsy, where will Pt tilt head if the left nucleus is damaged?
6. How does it travel to the SO?
7. Anatomical origin of SO?
8. Physiologic Origin of SO?

Answer 142

1. Longest (75 mm) and Skinniest CN
2. 2; 1 at Midbrain and 1 at Inferior Colliculus
3. Goes thru Superior Colliculus via Tectobulbar Tract then connects to visual cortex.
4. Leaves DORSAL side of brain and DECUSSATES
5. AWAY from the affected side…so to the right.
6. Enters LATERAL wall of Cavernous Sinus –> Travels underneath CN 3 –> Enters orbit SUPERIOR to ANNULUS of ZINN via SOF.
7. Lesser wing of SPhenoid bone
8. TROCHLEA

Question 143

CN 5

1. Motor/Sensory?
2. V1?
3. V2?
4. V3?
5. Travels how?

Answer 143

1. Both ORIGINATE in PONS
2. Sensory info: Head to tip of nose
3. Sensory info: Side of nose to mouth
4. Sensory info: Head and ear to mandible; Motor: Muscles of Mastication
5. Sensory: from face/head –> Cavernous Sinus –> Synapse on TRIGEMINAL GANGLION –> Sensory nuclei in Pons –> Info Sent To THALAMUS

Question 144

CN 5: V1

1. Nasociliary Nerve
   a. Sensory info from where?
   b. Branches?
   c. LPCNs? (Sympathy for your LONG DILATORS)
   d. SPCNs?
   e. Infratrochlear Nerve?
2. Frontal Nerve
   a. 2 branches?
   b. Supratrochlear Nerve
   c. Supraorbital Nerve
3. Lacrimal Nerve
   a. Purpose?
   b. Before entering Lacrimal Gland, it receives what?
   c. After leaving Lacrimal Gland, what does it supply?
4. Nerve supply of UPPER EYELID from Lateral to MEDIAL?

Answer 144

1. a. Cornea, Iris, Tip of nose.
   b. Long Ciliary Nerves; Short ciliary nerves; Infratrochlear nerve, and Ant and Post Ethmoidal Nerves

c. Sensory: Cornea, Iris, Ciliary Muscle; Symp Fibers: Dilator Muscle of Iris
d. Sensory: Cornea, Iris, Ciliary Muscle
e. Sensory: Medial Angle of Eyelids

2. a. Supratrochlear and Supraorbital nerves
   b. Sensory: Medial Portion of Upper eyelid and Conjunctiva
   c. Forehead, Scalp, Central PORTION of Upper eyelid and Conjunctiva
3. a. Sensory info for LACRIMAL GLAND
   b. PSN Fibers of CN7 from Zygomatic Branch of V2 (LACRIMATION)
   c. Lateral part of Conj and upper eyelids
4. Lacrimal –> Supraorbital –> Supratrochlear –> Infratrochlear. Sup Orbital Rim Trauma –> Damage to Supraorbital and Supratrochlear nerves –> Hypoesthesia of Ipsilateral Forehead

Question 145

CN5: V2: Maxillary Division

1. V2 travels how?
2. Infraorbital Nerve
   a. Enters what?
   b. Inn?
3. Zygomatic Nerve
   a. Travel?
   b. Inn?
   c. Carries what fibers w/it?
4. Nerve supply of Lower Eyelid from Lateral to Medial?

Answer 145

1. Inf Lateral part of Cavernous Sinus –> Enters FORAMEN ROTUNDUM on Greater wing of sphenoid –> Divides into 2 terminal branches before entering IOF
2. a. Maxillary bone via Infraorbital Foramen
   b. Lower Eyelids, Cheek, Upper Lip
3. a. Lateral from IOF and divides into 2 terminal branches
   b. LATERAL STRUCTURES (Lateral part of Forehead, Lateral Side of cheek, and Lateral Aspect of Lower Eyelid)
   c. PSN Fiber from Pterygopalatine Ganglion of CN 7 to Lacrimal Nerve of V1 to stimulate Lacrimation
4. Zygomaticofacial –> Infraorbital –> Infratrochlear Nerve (supply to majority of lower eyelid and upper eyelid)

Question 146

CN 5: V3: Mandibular Division

1. Sensory to what?
2. Motor to what?
3. CN5: THINK WHAT?

Answer 146

1. Sensory to lower face
2. Muscles of Mastication
3. SENSORY, SENSORY, SENSORY, w/a little bit of motor.

Question 147

CN 6

1. Abducens Nucleus: Location?
2. Leave nucleus b/w what 2 structures?
3. Papilledema: Increase in ICP can cause what?
4. CN6 Palsy can also occur from what?
5. CN 6 Palsy results in what kind of DEVIATION, Diplopia most apparent in what gaze, and Head turn toward which side?
6. CN 6 Passes thru what?

Answer 147

1. Pons
2. Pons and Medulla
3. LATERAL RECTUS PALSY d/t CN6 compression on Petrous RIDGE of Temporal Bone
4. ICA Aneurysm w/in Cavernous Sinus…sits close to ICA here.
5. ESO; Horizontal Diplopia at Distance; TOWARD AFFECTED SIDE
6. SOF –> CTR –> LR

Ciliary Ganglion is Medial to LR

Question 148

CN 7:

1. Purpose?
2. 3 Roots of CN7?
3. Voluntary Motor Root
4. Involuntary Motor Root
5. Sensory Root

Answer 148

1. Motor to facial expression muscles; PSN Fibers to Inner Ear and Facial Glands (Lacrimal Gland as well). Taste for Ant 2/3 of Tongue
2. Lg Motor Root, Small Sensory and PS root.
3. Facial Muscles (Orbicularis Oculi as well)
4. PS Fibers –> Stimulate secretions from facial Glands, LACRIMATION, and has a BRANCH to the STAPEDIUS MUSCLE of the MIDDLE EAR to DAMPEN SOUND!
5. Taste from Ant 2/3 of tongue

Question 149

CN 7: Course

1. Describe travel
2. A Nuclear lesion to what CN may also affect CN7?

Answer 149

1. Pre-Central Motor Cortex of Frontal Lobe –> Fibers descend in CORTICOBULBAR TRACT –> Pons (Facial motor and salivatory/lacrimal nuclei are found) –> Fibers leave nuclei –> Arch around abducens –> Exit Brainstem –> Enter INTERNAL AUDITORY CANAL in PETROUS PORTION of TEMPORAL BONE –> travel thru GENICULATE GANGLION ==> Greater Petrosal Nerve and Chorda Tympani Nerve branch off the main root of CN 7 –> rest of fibers exit Temporal Bone thru Stylomastoid Foramen ==> Enter PAROTID GLAND –> Divide into 5 BRANCHES
2. CN6.

Question 150

CN 7: Branches

1. Greater Petrosal Nerve
   a. This nerve joins what nerve? Forms what nerve?
   b. This newly formed nerve does what?
2. Chorda Tympani Nerve
   a. What is it?
3. Facial Expression
   a. Main Root of CN 7: 5 Divisions?
   b. Which innervates the Orbicularis Oculi?
   c. Which innervates the Procerus, Corrugator, Occipital Frontalis, and ORBICULARIS OCULI?
4. Does CN7 innervate the PAROTID GLAND?
5. If we remove an ACOUSTIC NEUROMA, what could be damaged?
6. CN7: THINK WHAT?

Answer 150

1. PS Inn –> LACRIMAL GLAND.
   a. Nerve Joins DEEP PETROSAL NERVE to form VIDIAN NERVE
   b. Travels to PTERYGOPALATINE Ganglion…PS Fibers synapse –> Post Fibers leave and Join ZYGOMATIC BRANCH of V2 –> Sends a communicating branch to LACRIMAL NERVE of V1 –> Innervates LACRIMAL GLAND!
2. Terminal Branch of CN 7 –> Taste from Ant 2/3 of Tongue and has PS Info to Submandibular and Sublingual Glands
3. a. Passes thru Stylomastoid Foramen –> enters parotid gland –> Temporal, Zygomatic, Buccal, Mandibular, Cervical Branches
   b. Zygomatic Branch
   c. Temporal Branch
4. NO!. CN9 does.
5. Parotid Gland and CN7
6. Motor, Motor, Motor, w/a little bit of sensory.

Question 151

Bells Palsy vs. Stroke

1. Upper neurons of CN 7 get what kind of input from the Cerebral Cortex?
2. Lower Neurons of CN 7 get what kind of input?
3. STROKE: what is it?
4. Bell’s Palsy: What is it?
   a. What can this cause?

Answer 151

1. B/L Input
2. C/L Input and Send innervation to I/L Facial Muscles
3. Supranuclear lesion = impaired C/L muscles of Lower FACE. Usually, C/L muscles of upper face are usually spared. (So basically just see drooping of mouth)
4. IDIOPATHIC Lesion of LOWER MOTOR NEURONS of CN7 –> Impaired innervation to Upper and LOWER I/L Facial Muscles –> Drooping of mouth and poor eyelid closure.
   a. Paralytic Lagophthalmos (most common form) and Secondary Exposure Keratopathy

Question 152

Sympathetic Innervation

1. 1st order Pre-ganglionic Fibers start where? Descend where?
2. 2nd Order Pre-ganglionic Fibers?
3. Post-Ganglionic Fibers?
4. In the Orbit, Sympathetic Fibers w/in ICA Plexus can follow 1 of 3 routes: What are they?
5. *Hyperactive SYMPATHETIC INNERVATION to BVs of the Choroid is thought to play a role in development of what?

Answer 152

1. Hypothalamus; to C8-T2 of spinal cord –> Synapse in CILIOSPINAL CENTER of BUDGE
2. Leave ganglion –> travel around clavicle and Across APEX of the LUNG (Pancoast Tumor) –> Sympathetic Chain on neck –> Ascend chain –> Synapse in SUP CERVICAL GANGLION
3. Forma Plexus (MOOCHER) around ICA –> enter skull via CAROTID CANAL
4. a. Sup Division of CN 3 –> Muller’s Muscle of upper eyelid
   b. Nasociliary nerve of V1 and branch w/either LPCNs (Iris Dilator and Ciliary Muscle) or SPCNs (Choroidal and Conjunctival BVs)
   c. BVs of Lacrimal Gland innervation via the VIDIAN NERVE
5. Central Serous Chorioretinopathy (contributes to localized damage in Bruch’s Membrane)

Question 153

Summary of SPCNs and LPCNs

1. SPCNs
2. LPCNs
3. Sensory info carried by both taken to what?

Answer 153

1. Origin: Ciliary Ganglion; Postganglionic Symp and PS Fibers to Many Ant Structures of the eye. Carry Sensory info from eye back to ciliary ganglion via NASOCILIARY NERVE
2. Branch from Nasociliary Nerve of V1, Crosses Optic Nerve. Carry Post-ganglionic Symp Fibers to the eye, and Sensory info from eye back to trigeminal Ganglion
3. Taken to TRIGEMINAL GANGLION for analysis

Question 154

Optic Nerve

1. Dura and Arachnoid Fuse together and become continuous with what?
2. Subarachnoid Space (b/w Arachnoid and Pia) of ON is continuous with what?
3. Why do 90% of pts w/OPTIC NEURITIS have PAIN on EYE MOVEMENTS?
4. Blood Supply
   a. Retinal NFL
   b. Intraocular ON
   c. Intraorbital ON
   d. Intracranial ON
5. can the ON AUTOREGULATE Its blood supply?

Answer 154

1. Periorbita and Sclera; DONT CONTINUE w/INTRACRANIAL PART of the ON.
2. with Subarachnoid space of Cranium and has CSF (reason for Papilledema w/increased ICP)
3. Because the ON Sheath is attached to the sheaths surrounding the SR and MR muscles.
4. a. SPCAs and CRA!
   b. (Pre-laminar and laminar layers): Circle of Zinn (formed by anastamoses of SPCAs)
   c. (Post Laminar): Branches of CRA and Pial Mater Arterial Plexus
   d. Ophthalmic, Ant Cerebral, ACA, and ICAs
5. YES (like the retina)…Choroid cannot do this.

Question 155

Optic Disc

1. Location from Fixation?
2. Subtends an angle of what?
3. ON: ONLY HAS what layers?
4. NO MULLER CELLS on Optic Disc. What covers it and what does it form?

Answer 155

1. 15 degrees
2. 5-7 degrees
3. NFL and ILM
4. Astrocytes; Forms the ILM of ELSCHNIG

Question 156

Optic Nerve: 4 regions

1. Intraocular Portion (1 mm)
   a. Extends from Optic Disc to what?
   b. Pre-Laminar ON: Does it have Myelin?
   i. What is The INTERMEDIARY TISSUE of KUHNT?
   ii. What’s the BORDER TISSUE of JACOBY?
   iii. What’s the BORDER TISSUE of ELSCHNIG?
   c. Laminar ON
   i. What is it?

Answer 156

1. a. to Lamina Cribrosa
   b. NO!
   i. Ring of Glial Tissue that separate ON Fibers from the retinal tissue that’s around it
   ii. The glial tissue that keeps going posteriorly and separates ON Fibers form the CHOROID
   iii. Scleral Collagen fibers that surround glial tissue

c. Part of ON that exits globe thru LAMINA CRIBROSA

Question 157

ON: 4 Regions: Region 2, 3, and 4

1. Intraorbital Portion (30mm)
   a. What part?
   b. S-shaped. Axons separated by CT Septa, allowing for what?
2. Intracanalicular (6-10 mm): area?
3. Intracranial (10-16 mm): Part of ON that extends from what to what?

Answer 157

1. a. Part from Lamina Cribrosa to where it exits the orbit via the Optic Canal
   b. eye movements w/o damage to the ON.
   * Point where they get MYELINATED!
2. Runs thru Optic Canal w/in the Cranium
3. Extends from the Optic Canal to the Optic Chiasm

Question 158

VF Damage

1. Papillomacular Bundle: Damage here can cause what kind of VF Defects?
2. Macular Dz usually causes what scotoma?
3. A nerve Dz that affects the Papillomacular Bundle can also do what?

Answer 158

1. Central, Centrocecal, and Paracentral VF Defects
2. Central Scotoma
3. Reduced VAs.

Question 159

Fiber Orientation at the Optic Chiasm

1. Anterior Knees of Wilbrand: What is it?
2. Posterior Knees of Wilbrand: What is it?
3. Optic Chiasm: What travels along the lateral edges?

Answer 159

1. INF NASAL FIBERS cross thru Optic Chiasm, loop ANTERIORLY into C/L Optic Nerve then enter the Optic tract
2. Sup NASAL FIBERS: Loop Posteriorly into the I/L Optic Tract then cross thru the Optic Chiasm
3. ICA and PCA; Optic Chiasm found w/in Circle of Willis

Question 160

Optic Tract: SMILe

1. Sup Fibers (nasal and Temporal) course to what side of the Optic Tract?
2. Inf Fibers Course to what side of the Optic Tract?
3. Macular Fibers travel where in the Optic Tract?

Answer 160

1. MEDIAL SIDE
2. LATERAL SIDE
3. MIDDLE of the Optic Tract

Question 161

LGN

1. Magnocellular Layers?
2. P-Layers?
3. Koniocellular Layers?
4. Superior Fibers synapse where in the LGN?
5. Inferior Fibers Synapse?
6. Macular Fibers form what Synapse?

Answer 161

1. Layers 1 and 2 (Located INFERIORLY)
2. Layers 3-6 (Extend SUPERIORLY)
3. Small cells located b/w each layer
4. MEDIAL LGN
5. LATERAL LGN
6. WEDGE of Synapses at DORSAL EDGE of the LGN and extend thru its entire thickness

Question 162

Optic Radiations

1. What are the fibers called that leave the LGN and travel to V1 (Primary Visual Cortex?)

Answer 162

1. OPTIC RADIATIONS

Question 163

V1: Primary Visual Cortex

1. Cuneus Gyrus
2. Lingual Gyrus
3. Macular fibers project to what area?
   a. Superior Macular Fibers Project to?
   b. Inf Macular Fibers to?
4. Way to remember: Lower Fibers course Laterally in the optic tract and form Meyer’s Loop then end at the Lingual Gyrus

Answer 163

1. Superior portion of VC. Superior retinal fibers end here
2. Inferior portion of V1 in occipital lobe. INFERIOR RETINAL FIBERS end here.
3. Outer Surface of the APEX of the Occipital Lobe. Make up ~50% of the fibers w/in V1.
   a. CUNEUS GYRUS
   b. LINGUAL GYRUS
   * THINK SCIL (SKILL)

Question 164

V1: P VC (2)

1. How many layers?
2. Purpose of Layer 4?
3. Layer 5?
4. Layer 6?
5. Vertical columns are organized into what? What do they do?
6. Where does BINOCULAR PROCESSING START?

Answer 164

1. 6 layers

2 Synapse b/w Optic Radiations and neurons of Striate Cortex. Fibers from P and M cells of LGN synapse in different parts of layer 4.

3. Axons sent to SUPERIOR COLLICULUS to control Saccadic Eye Movements
4. Gives feedback info back to the LGN.
5. OCULAR DOMINANCE COLUMNS w/Fibers from ONLY ONE EYE.
6. Starts at the level of the PRIMARY VISUAL CORTEX

Question 165

Blood Supply of Visual Pathway

1. Optic Chiasm
2. Optic Tracts
3. LGN
4. Optic Radiations
5. Primary Visual Cortex

Answer 165

1. Circle of Willis and Branches of ICA
2. Anterior Choroidal Branch of Middle Cerebral Arteries
3. Anterior Choroidal and Posterior Cerebral Arteries
4. Anterior Choroidal, Middle Cerebral, and Posterior Cerebral Arteries
5. Posterior Cerebral Artery and Middle Cerebral Artery. *Dual blood supply so if one is knocked out, one can still see.

Question 166

VF Defects

1. When is VAs affected w/Post-Chiasmal Lesions?
2. The macula receives blood supply from what arteries?
3. Most classic cause of a BITEMPORAL HEMIANOPSIA?
4. How does a JUNCTIONAL SCOTOMA usually present?

3,4 = lesions at Optic Chiasm

Answer 166

1. Only when a B/L Lesion is PRESENT!
2. Posterior and Middle Cerebral Arteries
3. PITUITARY GLAND TUMOR compressing nasal fibers
4. Central vision loss in one eye, and a SUPERIOR TEMPORAL LOSS in the other eye (due to compression of the Inf and Nasal Fibers)

Question 167

U/L Defect, Binasal Step, and/or Arcuate Scotoma = ?

Answer 167

1. Retinal or ON Pathology

Question 168

Retinal Lesions

1. 3 things

Answer 168

1. Asymmetric VF loss b/w the eyes
2. DO NOT respect horizontal or vertical midlines
3. can be B/L but are NOT Congruous