Dip at 4000hz in pure Tone audiometry indicates:-: (A) Otosclerosis, (B) Meniere's disease, (C) Noise induced hearing loss, (D) Age related hearing loss
Answer is C. 2000Hz / Carha's Notch: seen in otosclerosis (CHL)4000Hz Dip/boiler's notch :seen in noise induced hearing loss (SNHL)Both are seen in bone conduction.