[Sensorineural deafness and cochlear otosclerosis (author's transl)]

Area of Science:

• Otolaryngology
• Audiology
• Pathology

Context:

• Labyrinthine otosclerosis is a specific form of otosclerosis characterized by focal involvement of the labyrinthine capsule.
• Unlike other forms of otosclerosis, it does not involve stapes fixation, leading to a distinct presentation.
• Its prevalence varies widely in literature, ranging from 4% to 40%.

Purpose:

• To define labyrinthine otosclerosis and its clinical presentation.
• To analyze audiometric data in patients with verified otosclerosis.
• To differentiate sensorineural hearing loss caused by otosclerosis from age-related hearing loss (presbycusis).

Summary:

• Labyrinthine otosclerosis results in pure sensorineural hearing loss, with histology being well-understood.
• Radiographic findings may include demineralization or obliteration of labyrinthine bone.
• Audiometric analysis of 208 cases revealed sensorineural hearing loss from otosclerosis is twice that of presbycusis, often with good speech discrimination despite severe threshold loss.

Impact:

• Provides a clearer understanding of labyrinthine otosclerosis, aiding in diagnosis.
• Highlights the significant contribution of otosclerosis to sensorineural hearing loss, even after accounting for presbycusis.
• Suggests diagnostic criteria for labyrinthine otosclerosis when other explanations are insufficient.