Intracanalicular acoustic neurinomas

Area of Science:

• Neurosurgery
• Otolaryngology
• Neurology

Background:

• Acoustic neurinomas are tumors arising from the vestibulocochlear nerve.
• Intracanalicular acoustic neurinomas are a subset confined to the internal auditory canal.
• Early diagnosis and effective surgical management are crucial for preserving neurological function.

Purpose of the Study:

• To present the clinical characteristics, diagnostic methods, and surgical outcomes for patients with purely intracanalicular acoustic neurinomas.
• To evaluate the efficacy of the suboccipital surgical approach for these specific tumors.
• To assess the preservation rates of facial and cochlear nerve function post-surgery.

Main Methods:

• Retrospective review of 16 patients with intracanalicular acoustic neurinomas operated over 8 years.
• Analysis of diagnostic methods including magnetic resonance imaging (MRI) and air computed tomographic cisternography.
• Surgical treatment via the suboccipital approach with detailed assessment of nerve preservation and tumor recurrence.

Main Results:

• Intracanalicular acoustic neurinomas represented 2.7% of operated cases.
• Earlier onset of vestibular symptoms facilitated diagnosis.
• 100% facial nerve and function preservation; 100% anatomical and 57% functional cochlear nerve preservation.
• Complete tumor removal achieved in all cases with no recurrence during up to 8 years of follow-up.

Conclusions:

• The suboccipital approach is highly effective for intracanalicular acoustic neurinomas, offering excellent facial nerve outcomes.
• While anatomical cochlear nerve preservation is high, functional preservation remains a challenge.
• Early symptom recognition and advanced imaging are key for timely diagnosis and successful surgical management.