Otology and Neurotology
Otology and Neurotology
This domain tests middle-ear and lateral skull-base reasoning: sudden sensorineural hearing loss (SSNHL), chronic otitis media, cholesteatoma, and vestibular schwannoma. The exam favors time-critical decisions and correct use of imaging.
Core rules
- SSNHL is a drop of at least 30 dB across three contiguous frequencies within 72 hours. Start high-dose corticosteroids urgently, ideally within 72 hours, and obtain contrast-enhanced MRI of the internal auditory canals.
- In chronic suppurative otitis media, a central perforation usually causes conductive loss; avoid aminoglycoside drops when the tympanic membrane is perforated.
- Cholesteatoma often shows a marginal perforation, scutum erosion, and keratin debris; non-EPI diffusion-weighted MRI helps detect residual or recurrent disease.
- Asymmetric SNHL or unilateral tinnitus warrants MRI to exclude retrocochlear pathology.
Worked example
A 52-year-old presents with 2 days of left hearing loss and tinnitus but no vertigo. Audiometry shows a 35 dB SNHL at 1, 2, and 3 kHz. The correct move is urgent oral prednisone and MRI, not watchful waiting. If hearing does not recover, intratympanic steroids can be considered. The reasoning is that the pattern meets SSNHL criteria and retrocochlear disease must be excluded.
Traps
Do not attribute sudden loss to wax or Eustachian tube dysfunction without audiometry. Do not delay steroids for imaging. Do not use ototoxic drops in a perforated ear.