Surgical Treatment of Acoustic Neuromas Through Retrosigmoid Approach

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Naeem ul Haq
Syed Nasir Shah
Sadaf Safeer


Facial nerve; Neurofibromatosis; Retrolabyrinthine surgery; Retrosigmoid surgery; Translabyrinthine surgery; Vestibular Schwannomas


Background: Acoustic neuromas are rare, benign tumors arising from Schwann cells of vestibular portion of 8th cranial nerve. Frequent presenting symptoms are unilateral hearing loss, and subsequent tinnitus and vertigo.
Objectives: Surgical treatment of acoustic neuromas is to perk up patient outcomes and quality of life through development of safe, effective, and efficient surgical approaches.
Methods: The study was conducted at Mardan Medical Complex, Mardan, from January 2018 to January 2023, comprising 25 patients diagnosed with acoustic neuromas through CT scan and MRI. The tumor size was categorized based on its maximum diameter, with tumors less than 1.5 cm classified as small, tumors computing 1.5-3 cm classified as medium, and tumors > 3 cm classified as large, removed surgically through middle fossa, retrosigmoid and translabyrinth approach.
Results: We found that 56% of patients had small-sized tumors, 28% had medium and 16% had large-sized tumors. They were surgically managed and preserved hearing in 33.33, 25 and 0% of small, medium and large-sized tumors, respectively. Facial nerve was preserved in 85.71, 71.42 and 50% of patients of the former categories, respectively. No complications were seen in patients with small-sized tumors, 14.28% in medium and 25% in large-sized.
Conclusion: Surgical treatment is one of the mainstays of management, and relies on various factors, and goal of surgery should be to minimize complications and maximize functional outcomes. For instance, translabyrinthine approach involves the removal of large-sized tumors, middle fossa for small and retrosigmoid for medium-sized neuromas.

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