A Case of Recurrent Benign Episodic Unilateral Mydriasis and Decreased Visual Acuity and Review of the Literature

Abstract

Unilateral mydriasis has a variety of causes, some of which are life-threatening. Migraine with benign episodic unilateral mydriasis is a nonsurgical cause of anisocoria, with unknown underlying pathophysiology. This disorder is thought to be caused by an Adie’s pupil triggered by migraine due to overactivation of the sympathetic nervous system or hypoactivity of the parasympathetic nervous system. We present the case of a 47-year-old patient who had recurrent benign episodic unilateral mydriasis associated with migraine headaches. Other vascular causes of mydriasis were investigated and excluded. Ultimately, the patient’s symptoms of blurred vision and pupillary dilation resolved over the 2 weeks after onset. We reviewed all 50 cases of benign episodic unilateral mydriasis reported in the literature and summarized common presentations of this disorder. The case presented here is typical in its progression and associated symptom of blurred vision, which is reported in 56% of cases in the literature.