The clinical spectrum of schwannomas presenting with visual dysfunction: Aclinicopathologic study of three cases

Schwannomas (neurilemomas) are benign tumors that arise from Schwann cells in the peripheral nervous system. The most commonly involved nerves that ca use neuro-ophthalmic manifestations are cranial nerves V and VIII. In this series of three women, schwannomas presented as intraconal masses that mimi cked a cavernous hemangioma, a superior orbital mass transgressing the supe rior orbital fissure, and an expansive frontal lobe mass with clinical symp toms and signs of increased intracranial pressure. Although all three compl ained of visual blur-ring, none of our patients presented with Vth or VIIIt h cranial nerve dysfunction. Histopathologic studies demonstrated well-circ umscribed, encapsulated spindle-cell lesions with classic Antoni A and B pa tterns. Histopathologic examination is essential to confirm the diagnosis o f a schwannoma that may be otherwise clinically confusing. Direct optic ner ve compression, globe indentation with induced hyperopia, or increased intr acranial pressure with optic nerve compromise may be responsible for visual symptoms. A multidisciplinary approach is often required because of the si ze and location of schwannomas. (C) 1999 by Elsevier Science Inc. All right s reserved.