Radiological Evaluation of Inner Ear with Computed Tomography in Patients with Unilateral Non-Pulsatile Tinnitus

Area of Science:

• Otolaryngology
• Radiology
• Neuroscience

Background:

• Tinnitus, a phantom auditory sensation, affects millions globally.
• The underlying pathophysiology of tinnitus is not fully understood.
• Inner ear bony structures may play a role in tinnitus development.

Purpose of the Study:

• To investigate the relationship between tinnitus and specific bony inner ear structures.
• To assess if computed tomography (CT) can identify structural abnormalities associated with tinnitus.

Main Methods:

• Prospective, controlled, double-blind study involving three groups: tinnitus with hearing loss, tinnitus without hearing loss, and healthy controls.
• Measurement of basal turn length, internal acoustic canal (IAC) width and length, bony cochlear nerve canal (BCNC) width, and IAC diameter at the porus acousticus internus (PAI) using CT.
• Statistical analysis to compare measurements between groups.

Main Results:

• Significantly narrower BCNC width in patients with tinnitus (both with and without hearing loss) compared to healthy controls (p<0.001).
• In patients with tinnitus but normal hearing, BCNC width was narrower in the affected ear (p<0.001).
• Narrower IAC diameter at the PAI was observed in patients with hearing loss and tinnitus (p=0.007).

Conclusions:

• CT evaluation of inner ear bony structures is crucial for patients with tinnitus.
• A narrow BCNC is strongly associated with tinnitus and may indicate cochlear nerve dysfunction.
• Clinicians should carefully evaluate BCNC width in tinnitus patients to identify potential causes.