Adie's Tonic Pupil.

A 33-year-old woman with no past medical history presented to the emergency department with asymmetric pupils. At 7:30am while putting on makeup, she noted her pupils were equal in size. One hour later, she developed light sensitivity in her right eye, and soon after noticed her right pupil was significantly enlarged. She denied headache, facial or extremity weakness, dysarthria, or ataxia. On exam, her left pupil was reactive from 4 to 3 mm and her right pupil was sluggishly reactive and 8 mm (Figure). No abnormalities in her visual acuity, extraocular movement or fundoscopic exam were detected. Neurologic consultation was obtained, but the patient had an unremarkable brain computed tomography (CT)/CT-Angiography and magnetic resonance imaging.

Figure.

Photograph of 33-year-old female presenting with asymmetric pupils.

A tonic pupil results from parasympathetic denervation at the level of the ciliary ganglion. It is characterized by a large, regular pupil with decreased response to light but preserved or enhanced constriction to accommodation, segmental iris constriction, vermiform movements of the pupillary border, and hypersensitivity to pharmacologic constricting agents.1–4 The diagnosis was established in consultation with ophthalmology and confirmed with rapid miotic response of the affected pupil to 0.125% pilocarpine drop.1,2 Most cases are idiopathic, occurring in women 20–40 years of age, and referred to as the Adie’s tonic pupil, though this disorder can be due to local disorders within the orbit, including tumor, inflammation, trauma, surgery, ischemia or infection. 3 Most patients do not require any treatment and can be reassured once the diagnosis is confirmed.