What clinical features are associated with otitis externa?
pruritis, pain, foul-smelling odor, and discharge
What are the predisposing factors that may lead to otitits externa?
Conformation/breed predispositions, behavior of the patient, environment, trauma, obstructive disease, and immunosuppressive diseases
What conformation/breed predispositions predispose patients to otitis externa?
long, tortuous ear canal, stenotic pinnae, hair in the external ear canal, and thick, dense hair at the opening of the external ear canal
What behavior of a patient can predispose them to developing otitis externa?
swimming or excessive bathing
What environmental conditions can predispose to otitis externa?
high environmental temperatures and high relative humidity increase the risk of otitis
What does the external canal consist of?
skin overlaying cartilage - auricular and annular cartilage
What part of the external ear canal does the auricular cartilage make up?
the ventral canal
What part of the external ear canal does the annular cartilage make up?
the horizontal canal
True or False: Only certain breeds have hair follicles in their ear canal.
False - all breeds have hair follicles in their ear canals, some just have hairier ears
When visualising the tympanic membrane, what structures can you see?
Pars flaccida, pars tensa, and malleus
external ear canal
The pars flaccida can change appearance based on ______.
What primary factors can induce otitis externa?
ectoparasites, foreign bodies, allergies, scaling disorders, autoimmune skin diseases, and juvenile cellulitis
What ectoparasites can cause otitis externa?
Otodectes cynotis, Otobius megnini, Sarcoptes scabeii, Notoedres cati, Demodex, and Cheyletiella
What is the most common primary factor of otitis externa in the dog?
What are the perpetuating factors for otitis externa?
bacteria, yeast, otitis media, erroneous treatment, proliferative/pathological changes of the external ear canal, and polyps
What are the most common bacterial isolates in inflamed ears of dogs?
Staphylococcus pseudintermedius, Proteus mirabilis, Pseudomonas aeruginosa
What are the most common bacterial isolates in inflamed ears of cats?
Staphylococcus pseudintermedius and Pasteurella multocida
What are some pathological changes that can occur in the ear?
inflammation, glandular hyperplasia, epidermal hyperplasia, additional inflammation, fibroplasia, and ossification
What is evidence based medicine?
conscientious, explicit, and judicious use of current best evidence in making decisions
What are 'best practicies'?
Procedures/methods shown by research and experience to produce optimal results that are established or proposed by experts in a field as a standard for use - used to provide clinical practice guidelines
What are the best practices in the management of otitis?
1. Use appropriate diagnostics
2. Prepare the canal for treatment
3. Choose treatment wisely
4. Medications must be administered properly
5. Use quality control to evaluate the environment
6. Consider long-term maintenance therapy
7. ID and control primary factors
What are the appropriate diagnostics for diagnosing otitis externa?
medical history, PE, otoscopic examination, cytology, culture and sensitivity, and diagnostic imaging
What are the keys/goals of otoscopic examination?
examine both canals, visualize the tympanic membrane, and do no harm (may need sedation/anesthesia as necessary)
What tools can be used for otoscopic examination?
otoscopes, pneumo-otoscopy, and video otoscope
What are the benefits to using a video otoscope?
increased magnification over hand held otoscopes, better light and clarity, and they give you the ability to adapt better for individuals visual defecits
What is the 'key' diagnostic test in otology?