Flashcards in Lecture 16: Anatomy and Histology of the Ear Deck (59)
What composes the external ear?
Auricle to Tympanic Membrane
What composes the middle ear?
Tympanic Membrane to Oval Window
What composes the inner ear?
Oval Window to Internal Acoustic Meatus
What type of cartilage is the external ear mostly made up of?
What supplies the external ear?
Posterior Auricular Artery (from ECA)
Superficial Temporal Artery (from ECA)
What provides sensory innervation to the external ear?
1. Facial Nerve
2. Cervical Plexus: Lesser Occipital and Greater Auricular Nerves
3. Auriculotemporal Nerve (V3)
4. Vagus/Glossopharyngeal Nerve
What innervates the superior part/roof of the external acoustic meatus?
What innervates the posterior part of the external acoustic meatus?
Greater Auricular Nerve (Cervical Plexus)
What innervates the anterior part of the external acoustic meatus?
Auriculotemporal Nerve (V3)
What innervates the inferior part/floor of the external acoustic meatus?
Vagus: Arnold Nerve
-plays a role in the cough reflex
What glands make ear wax?
What is the composition of the external acoustic meatus?
Outer ⅔: Soft CT and Cartilage (similar to external ear)
-where you can see ceruminous and sebaceous glands + hair follicles
Inner ⅓: Just skin and bone
Where is the cone of light?
Anterior, inferior quadrant of Tympanic Membrane
What makes up the roof of the middle ear?
Tegmental Wall (from Temporal Bone)
-Separates ear from brain/middle cranial fossa
What makes up the floor of the middle ear?
-Separates ear from bulb of Internal Jugular Vein
What makes up the lateral wall of the middle ear?
Membranous Wall (going to external ear)
What makes up the medial wall of the middle ear?
What is found at this wall?
Labyrinthine Wall (Oval and Round Windows)
-Lateral Semicircular Canal
-Facial Canal and Nerve
-Promontory of Labyrinthine Wall
What makes up the posterior wall of the middle ear?
-Separates tympanic cavity from mastoid air cells and facial canal
What can be found at the anterior wall of the middle ear?
Tensor Tympanic Muscle
-Separates Tympanic Cavity from Internal Carotid Artery
What does the pharyngotympanic tube connect?
Middle ear to nasopharynx
What does the pharyngotympanic tube do?
What two muscles expand the pharyngotympanic tube?
Levator Veli Palatini Muscle
Tensor Veli Palatini Muscle
What type of epithelium is found on the pharyngotympanic tube?
What three bones make up the auditory ossicles in the middle ear?
What pharyngeal arches are they from?
Malleus (PA 1)
Incus (PA 1)
Stapes (PA 2)
What does the auditory ossicles do?
Transmit sound from the air to the fluid filled concha
What does the Tensor Tympani Muscle do?
What nerve innervates it?
Dampens loud sounds by pulling on handle of malleus
Innervated by CN V3
What does the Stapedius Muscle do?
What nerve innervates it?
Dampens vibrations and limits excess movement of stapes bone (at the neck)
Innervated by CN VII
Where is the bony labyrinth located?
Petrous Region of Temporal Bone
What separates bony labyrinth with membranous labyrinth?