(a) Otosclerosis(Ref. Cummings, 6th ed., 2211)30-yr-old woman with family history of hearing loss, presenting with B/L hearing loss during pregnancy, pure tone audiometry showing an apparent bone conduction hearing loss at 2000Hz, i.e. Carhartz notch is diagnostic of otosclerosis.Acoustic neuroma is seen in the age group of 40-70 yrs and presents with U/L SN hearing loss and tinnitus.Otitis media with effusion or glue ear is seen most commonly in children and presents with B/L conductive hearing loss. Tympanic membrane here is dull retracted with fluid level and air bubbles seen behind.Sigmoid sinus thrombosis is a complication of unsafe CSOM and presents with hectic fever, jugular vein area tenderness, oedema of the mastoid and features of unsafe CSOM, i.e. ear discharge, cholesteatoma, and hearing loss.