Rollover phenomenon in audiometry is seen in: (A) Cochlear lesions, (B) Retro-cochlear lesions, (C) Lesion in inferior colliculus, (D) Lesion in medial geniculate body
Answer is B. Roll over phenomenon:- it is seen in retro cochlear hearing loss . With increase in intensity above paicular level phonetically balanced score (PB score) falls rather than maintain a plateau as in cochlear type of sensineural hearing loss .