459.A 65-year-old man with a history of diabetes, hypertension, coronary
artery disease, and atrial fibrillation presents with loss of vision in his left eye
since he awoke 6 hours ago. The patient denies fever, eye pain, or eye dis-
charge. On physical examination of the left eye, vision is limited to counting
fingers. His pupil is 3 mm and reactive. Extraocular movements are intact.
Slit-lamp examination is also normal. The dilated funduscopic examination
is shown below. Which of the following is the most likely diagnosis?
496 Emergency Medicine
a. Retinal detachment
b. Central retinal artery occlusion
c. Central retinal vein occlusion
d. Vitreous hemorrhage
e. Acute angle closure glaucoma
(Reproduced, with permission, from Knoop KJ, Stack LB, Storrow AB.Atlas of Emergency
Medicine. New York, NY: McGraw-Hill, 2002: 82.)