IDIOPATHIC INTRACRANIAL HYPERTENSION PRESENTING WITH GAZE-EVOKED AMAUROSIS

Purpose: Gaze-evoked amaurosis is transient monocular visual loss indu ced by an eccentric position of gaze, most frequently associated with orbital mass lesions. To our knowledge, there has been no reported cas e of idiopathic intracranial hypertension as a cause of gaze-evoked am aurosis, We present the hypothesis that in an eccentric position of ga ze, ischaemic compression of a tense dilated optic nerve sheath result s in further elevation of intrasheath pressure compromising blood flow to the retina. Method: We describe a case of unilateral gaze-evoked a maurosis and headaches in a 46 year old man diagnosed with idiopathic intracranial hypertension, He did not respond to medical treatment and had optic nerve sheath decompressions. Result: Following surgery, thi s patient's visual function improved with resolution of his gaze-evoke d amaurosis. Conclusion: Raised intracranial pressure associated with a tense dilated optic nerve sheath should be considered in the differe ntial diagnosis of gaze-evoked amaurosis.