Contralateral Upper Motor Neuron Facial Palsy in a Case of Vestibular Schwannoma: A Consequence of an Underrecognized Anatomical Entity

Abstract Neurological deficits due to vestibular schwannoma (VS) result from either direct compression on the ipsilateral long tracts and cranial nerves, or strain over the contralateral cranial nerves due to angular distortion. However, the occurrence of a contralateral isolated upper motor neuron (UMN) facial palsy in a case of VS is a rare phenomenon, presenting as a clinical localization puzzle. This is the first case report of a contralateral isolated UMN facial palsy due to VS, elucidating the plausible pathophysiological mechanism.