Noise induced hearing loss
Answer – A. Otosclerosis
Most likely diagnosis is otosclerosis as the given audiogram shows a conductive pattern of hearing loss (BC >AC) with Carhart’s notch, a dip in bone conduction at 2,000 Hz is seen.
Audiometry in Otosclerosis
- Conductive hearing loss occurs in otosclerosis (BC >AC)
- Impedance audiometry: Patients with early disease may show type A tympanogram
- Progressive stapes fixation results in As type curve
- Acoustic reflex: lt is one of the earliest sign’s of otosclerosis & precedes the development of an air-bone gap
- In the early stages of otosclerosis, a characteristic diphasic on-off pattern is seen there is a brief increase in
(A)There is a brief increase in compliance at the onset and the termination of stimulus occurs. This is pathognomic for otosclerosis.
(B)In later stages, the stapedial reflex is absent.
A Carhart’s notch: A dip in bone conduction at 2,000 Hz is seen.