Parinaud's syndrome due to a /INS;unilateral vascular ischemic lesion

Abstract

Background: Parinaud'/INS;s syndrome includes as core feature /INS;paralysis of conjugate vertical eye movements (especially upgaze) with convergence–/INS;retraction nystagmus on attempted upgaze. Since the lesions accounting for the paralysis of voluntary vertical eye movements are located adjacent to the pupillomotor pathways, there can be varying degrees of paralysis of convergence, pupillary constriction, and accommodation. Parinaud's syndrome may be caused by extrinsic or intrinsic lesions, with pineal tumors and hydrocephalus being common etiologies.