A 64-year-old Chinese female presented to the Wills Eye Hospital Neuro-ophthalmology Service for evaluation of decreasing vision after cataract surgery in the left eye. She was originally seen by her primary ophthalmologist outside of Wills eight weeks prior for evaluation of cataracts and was found to have 3+ nuclear sclerosis in both eyes with uncorrected vision of 20/40 and 20/70. She underwent uncomplicated cataract extraction with posterior chamber intraocular lens implantation in the left eye, but the three week postoperative visual acuity was 20/100 with pinhole to 20/70. There was no afferent pupillary defect, extraocular movements were full and intraocular pressure was 15 mmHg in both eyes. Optical coherence tomography of both the macula and optic nerve was normal. She was treated with Pred Forte 1% four times daily, but returned to her ophthalmologist three days later with a vision of count fingers at 3 feet. She was then referred to the Wills Eye Neuro-ophthamology service for evaluation. She denied any numbness, tingling, weakness, headache, jaw claudication, pain on eye movement, myalgias or fevers on presentation.

Medical History 
Past medical history was significant for hypertension and cataract in the right eye. She was on unknown anti-hypertensive medications. Family history was non-contributory.

Ocular examination in the neuro-ophthalmology clinic at Wills revealed visual acuity of 20/25 in the right eye and count fingers at 5 feet in the left eye with a 3+ afferent pupillary defect on the left. Motility was full and IOP was 15 mmHg in the right eye and 12 in the left eye. She correctly identified 11 of 11 color plates in the right eye but only the test plate in the left eye. Slit-lamp examination was notable only for 3+ nuclear sclerosis in the right eye and a PCIOL in the left eye. Dilated fundus examination was unremarkable in the right eye and in the left showed posterior vitreous detachment, attenuated vessels and a pale optic nerve without elevation, edema or hemorrhages.

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