Term
What are the 2nd branchial arch (reichert cartilage) derivatives? |
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Definition
1) Stylohyoid ligament 2) Superior body and lesser corneu of hyoid 3) Manubrium of malleus, long process incus, stapes suprastructure |
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Term
Describe nystagmus in vestibular neuritis |
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Definition
Oppose site of origin,, horizontal and rotary, lasting days to weeks |
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Term
What is utility of flouride in otosclerosis? |
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Definition
Slows progression, does not reverse |
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Term
What are the most common patterns spread from prussak's space of cholesteatoma? |
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Definition
Epitympanic cholesteatoma arises in prussaks space (between pars flaccida and neck of malleus)
Most common posterior epitympanum
Less common posterior mesotympanum then anterior epitympanum |
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Term
What is the most common site of spontaneous perilymphatic fistula? |
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Definition
Anterior to anterior crus
less common is anteroinferior to anterior crus and then anterosuperior to anterior crus |
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Term
What is the relevance surgically of the cochleaform process? |
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Definition
Geniculate ganglion lies superior to it (near first geneu distal part of labrynthine segment) |
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Term
What is Cogan's syndrome? |
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Definition
Interstitial keratitis, recurrent vertigo, unilateral or bilateral SNHL.
Autoimmune disorder. |
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Term
What vascular anomaly is associated with a persistent stapedial artery? |
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Definition
Absent middle meningeal, absent foramen spinosum |
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Term
What is the blood supply of the utricle? |
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Definition
Anterior vestibular artery (also superior and horizontal SCC and small portion of saccule) |
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Term
Most vesibulotoxic aminoglycoside |
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Definition
Streptomycin (followed by Gentamycin) |
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Term
MRI appearance of cholesteatoma |
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Definition
Isointense on T1 and does not enhance with contrast Hyperintense on T2 and shows diffusion restriction on DWI |
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Term
What is Scheibe's anomaly? |
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Definition
- Dysplasia of cochleae and saccule, also known as cochleosaccular dysgenesis.
Involves membranous portion of the pars inferior |
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Term
What are the contents of the cochlear aqueduct and where does it connect? |
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Definition
Periotic duct
Connects scala tympani at basal turn of cochlea to the SAS. |
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Term
How do you differentiate peripheral from central vertigo? |
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Definition
1) Peripheral improves with fixation. Central does not 2) Smooth pursuit tracking is most sensitive for central 3) Pure vertical and nystagmus that changes direction in fixed head position suggests central |
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Term
What are the classic features of Pendred syndrome? |
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Definition
Thyroid goiter, defective ion transport, bilateral EVA, mondini malformation |
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Term
Why is the risk of iatrogenic cholesteatoma higher after lateral compared to medial graft tympanoplasty? |
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Definition
Incomplete removal of squamous epithelium. They take longer to heal and can have blunting. |
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Term
What are the histopathologic features of acoustic neuromas?
How is this different from meningioma? |
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Definition
Densley packed spindle-shaped Schwann cells (Antoni A) interspersed amidst loosely packed connective tissue (Toni B).
Verocay bodies (clear regions surrounded by palisading nuclei)
They are 90% of CPA lesions
Meningiomas instead have spindle shaped celled in nests with psammoma bodies |
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Term
How can you avoid post-operative blunting after lateral graft tympanoplasty? |
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Definition
1) Remove anterior canal wall bulge 2) Avoid direct placement of graft over anterior canal bone 3) Place canal packing over graft into anterior sulcus 4) Ensure overlapping of canal skin and graft |
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Term
What is size criteria for gamma knife for acoustic neuroma? |
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Definition
Not >3cm (swelling and hydrocephalus can occur with big tumors) |
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Term
What are the autosomal recessive conditions of hearing loss? |
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Definition
1) Pendred 2) Usher 3) Jervell and Lange-Nielson
Less common and more severe |
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Term
What are the X-linked causes of congenital hearing loss? |
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Definition
X-linked stapes gusher, Alport, Otopalatodigital syndrome |
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Term
What about recruitment can indicate a retrocochlear lesion? |
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Definition
Absence of recruitment in setting of known SNHL |
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Term
What is the sunderland nerve injury classification? |
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Definition
Class 1: Neuropraxia (compression) Class 2: Wallerian degeneration Class 3: Neurotmesis Class 4: Violation of perineurium Class 5: Complete transeciton |
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Term
Describe childhood hearing evaluations appropriate by age |
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Definition
1) <6 months: BOA 2) 6-30 months: VRA 3) >30 months: CPA |
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