Man referred for acute onset of distortions, decreased vision

A 53-year-old man was referred for cataract evaluation at Lahey Medical Center. Over the previous month, he noticed a gradual decrease in vision to the point where he had difficulty driving and functioning in his career as a mailman. His primary complaint was “difficulty focusing” at far and near despite a recent prescription for new glasses.

The patient denied any alleviating or aggravating factors. His medical history was significant for poorly controlled insulin-dependent diabetes and multiple prior deep venous thromboses. He was a glaucoma suspect based on optic nerve asymmetry. His family history was noncontributory.

Examination

The patient’s best corrected visual acuity was 20/50 in the right eye and 20/30-3 in the left eye. IOPs and pupil exam were normal. Anterior segment exam showed 2+ nuclear sclerosis. Posterior segment exam was normal with the exception of mild cup-to-disc asymmetry.

Because the patient’s symptoms were out of proportion to the exam findings, he was referred for neuro-ophthalmic testing. He demonstrated bilateral color desaturation. He had difficulty initiating pursuit and saccades. Pursuit was saccadic, and saccades were hypometric. Ocular motility was overall full, but he had esotropia of 10 ∆D to 12 ∆D on exam. Humphrey visual field showed a right homonymous field defect. The optic nerve and macula were both normal on optical coherence tomography. A brain MRI without gadolinium, ordered by his outside family physician, was read as normal.

When questioned regarding personality or cognitive changes, the patient’s family reported he recently had occasional outbursts that were uncharacteristic for him, which were thought to be due to frustration with his vision.

What is your diagnosis?

Click here to read the full publication exclusive, Grand Rounds at the New England Eye Center, published in Ocular Surgery News U.S. Edition, October 25, 2014.