Otology, neurotology and audiological interpretation
Build your otology reasoning around three frameworks: (1) conductive vs. sensorineural hearing loss on tuning forks and audiometry; (2) the site-of-lesion approach to vertigo (peripheral vs. central); and (3) temporal bone anatomy as it relates to complications and the facial nerve.
For hearing loss, know Weber and Rinne cold: Weber lateralizes to the conductive-loss ear (or better cochlea); Rinne is negative (bone > air) in conductive loss. Recognize sudden sensorineural hearing loss (SSNHL) as an emergency, prompt appropriate assessment and audiometric confirmation, with consideration of corticosteroid therapy in an eligible patient and evaluation for retrocochlear pathology by the relevant pathway. Differentiate otosclerosis (young adult, progressive conductive loss, normal tympanic membrane) from chronic otitis media with effusion and cholesteatoma (epitympanic retraction, scutum erosion, foul discharge).
For continuous acute vestibular syndrome with nystagmus, a suitably trained clinician can use HINTS in the applicable setting: normal head impulse, direction-changing nystagmus, and skew deviation suggest central pathology. BPPV is diagnosed by the Dix-Hallpike maneuver and treated with canalith repositioning; vestibular neuritis follows a viral prodrome with a positive head impulse; Ménière disease features episodic vertigo, fluctuating hearing loss, tinnitus, and aural fullness.
Traps: missing a central cause by anchoring on "peripheral"; treating SSNHL as "watch and wait"; and forgetting that facial nerve decompression decisions depend on whether paralysis is complete and whether function is preserved.
Clinical boundary: Sudden hearing loss needs timely evaluation, but not every case has one vascular mechanism or an identical treatment indication.
Worked example: A 48-year-old with acute vertigo, vomiting, and horizontal nystagmus has a positive head impulse test and no skew deviation. This pattern favors a peripheral cause (vestibular neuritis); the complete acute-vestibular assessment is still required. A partial examination or an untrained interpretation does not safely exclude a central cause.
Interpret the actual test
A tuning-fork result is a bedside contribution, not a substitute for audiometric characterization. Severe unilateral sensorineural loss can create misleading apparent bone-conduction responses through the opposite cochlea. Tympanometry evaluates middle-ear mechanics and pressure rather than directly measuring cochlear function. A type As pattern supports stiffness but does not uniquely prove stapes fixation in every patient. Speech discrimination, acoustic reflexes, evoked responses and imaging answer different localization questions. A suggestive acoustic-reflex decay result raises concern rather than independently establishing a vestibular schwannoma. Hearing rehabilitation also depends on residual function, anatomy, aided performance and the applicable device criteria; one universal sentence-recognition threshold cannot establish candidacy in every country or device program.