11. Otosclerosis, tympanosclerosis
- Otosclerosis
- Abnormal bone growth of the bony labyrinth
- The stapes becomes increasingly fixated to the oval window -> progressive conductive HL
- Can also affect cochlea
- Epidemiology
- Whites
- Females
- Adults
- 50% autosomal dominant, 50% sporadically
- Diagnosis
- Decreased air conduction on pure tone
- Carhart notch on audiogram
- Normal otoscopy
- Treatment
- Stapes replaced by prosthesis – stapedotomy
- Tympanosclerosis
- Scarring of tympanic membrane and cavity due to recurrent otitis externa or media
- Asymptomatic or conductive hearing loss due to fixation of ossicles
- White calcified plaques on otoscopy
- Myringosclerosis – only tympanic membrane
- Rarely symptoms
- Treatment
- Surgical removal of sclerosis
- Usually recurs
- Surgical removal of sclerosis