An Adult With Unilateral Mydriasis

Karima S. Khimani; Rod Foroozan, MD


October 04, 2017

Case Presentation

A 34-year-old man presents with a 2-week history of anisocoria, with the right pupil larger than the left. He noted a gradual increase in the size of his right pupil that had then become slightly smaller. He reported occasional blurred vision and difficulty reading. He denied any diplopia or eye pain. He also noted intermittent headaches.

The patient has a medical history of hyperlipidemia and anxiety. His family history is significant for diabetes mellitus in his father. The patient is a former smoker but has no history of alcohol or drug abuse. He is currently taking fluticasone and loratadine for seasonal allergies but is not using any eye drops.

Best corrected visual acuity was 20/20 in the right eye and 20/25 in the left eye. Near vision was J1+ bilaterally. Color vision with Ishihara pseudoisochromatic color plates was 10/10 in both eyes. Amsler grid testing was normal in both eyes. Pupils were unequal in size in the dark (9 mm right eye, 4.5 mm left eye), with minimal constriction to light on the right side (8 mm right eye, 3 mm left eye). There was light-near dissociation of the right pupil. The left pupil was brisk. No relative afferent pupillary defect was noted. The visual fields and extraocular movements of both eyes were full, and he was orthotropic in all positions of gaze. Intraocular pressures were 20 mm Hg in the right eye and 15 mm Hg in the left eye. There was no resistance to retropulsion of the globes.

Slit lamp examination of the anterior segment and dilated fundus examination were normal.

CT and MRI of the brain obtained around the time of the onset of anisocoria were said to be normal.


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