Sinonasal Ancient Schwannoma Presenting as Unilateral Blindness

Abstract

Schwannomas, also known as neurilemmomas, are benign nerve sheath tumors originating from Schwann cells of the peripheral nervous system. Sinonasal schwannomas are rare, comprising approximately 4% of all schwannomas. These tumors are typically slow growing, often leading to delayed clinical presentation. Despite their benign nature, their indolent progression can result in significant morbidity due to mass effect on adjacent vital structures. We report a case of a large, late-diagnosed right sinonasal ancient schwannoma causing extensive compression of surrounding tissues, including the right frontal and temporal lobes, ultimately resulting in vision loss due to compressive optic neuropathy. Ocular symptoms may be the initial manifestation of sinonasal tumors and should raise concern for potentially aggressive lesions. Prompt recognition and early referral are critical to minimize complications and improve patient outcomes.