Hearing preservation in neurofibromatosis type 2

Area of Science:

• Neurosurgery
• Otolaryngology
• Genetics

Background:

• Neurofibromatosis type 2 (NF2) is a genetic disorder characterized by the development of tumors, primarily bilateral vestibular schwannomas (acoustic neuromas).
• Surgical intervention for acoustic neuromas in NF2 patients aims to balance tumor removal with the preservation of neurological function, particularly hearing and facial nerve integrity.

Purpose of the Study:

• To review the clinical outcomes of the middle fossa approach for hearing preservation in patients with neurofibromatosis type 2 (NF2).
• To evaluate the efficacy of this surgical technique in maintaining audiological function and facial nerve function in NF2 patients.

Main Methods:

• Prospective case review of 18 patients (23 procedures) with NF2 undergoing middle fossa surgery for acoustic neuroma removal.
• Audiological assessment using American Academy of Otolaryngology-Head and Neck Surgery criteria and pure-tone average (PTA) with speech discrimination.
• Facial nerve function assessed using the House-Brackmann grading system.

Main Results:

• Measurable hearing preservation was achieved in 65% of patients; 48% maintained hearing within 15 dB of preoperative pure-tone average and 15% of speech discrimination.
• Excellent facial nerve function (House-Brackmann grades I-II) was preserved in all patients with normal preoperative function.
• Bilateral hearing preservation was observed in five patients.

Conclusions:

• The middle fossa approach yields hearing preservation and facial nerve function outcomes comparable to those seen in sporadic unilateral acoustic neuromas.
• Early surgical intervention is critical for achieving favorable hearing and facial nerve outcomes in NF2 patients.
• This approach represents a viable option for managing acoustic neuromas in NF2 while prioritizing hearing preservation.