Sensorineural hearing loss: more than meets the eye?

Area of Science:

• Radiology
• Neurology
• Otolaryngology

Background:

• Sensorineural hearing loss (SNHL) can stem from diverse pathologies affecting the auditory system.
• Acoustic neuromas are a common cause of SNHL, but other lesions also contribute significantly.
• Identifying the precise cause of SNHL is vital for appropriate patient management.

Purpose of the Study:

• To evaluate the diagnostic utility of magnetic resonance (MR) imaging in identifying causes of SNHL.
• To assess MR's effectiveness in detecting lesions other than acoustic neuromas within the auditory pathway.

Main Methods:

• Retrospective review of MR studies in 51 patients diagnosed with SNHL.
• Exclusion of patients with acoustic neuromas to focus on less common etiologies.
• Analysis of lesions within the labyrinth, internal auditory canal, cerebellopontine angle, and brain stem.

Main Results:

• Labyrinthine lesions were identified in 20 patients, including various forms of labyrinthitis and hemorrhage.
• Intracanalicular and cerebellopontine angle lesions were found in 13 patients, encompassing arteriovenous malformations, inflammatory, and neoplastic conditions.
• Intra-axial lesions, primarily brain stem infarcts and multiple sclerosis, were responsible for SNHL in 18 patients.

Conclusions:

• MR imaging is valuable for detecting a wide spectrum of SNHL causes beyond acoustic neuromas.
• Comprehensive evaluation of the entire acoustic pathway, including the labyrinth and brain stem, is recommended for SNHL patients.
• Contrast-enhanced MR significantly improves the detection of inflammatory and neoplastic lesions affecting the auditory system.