A 69-year-old man comes to the emergency department with 1 hour of sudden vision loss in his right eye. The patient has no headache, eye pain, itching, or discharge. He has a history of coronary artery disease, type 2 diabetes mellitus, hypertension, and hyperlipidemia. The patient was diagnosed with prostate cancer 6 months ago and treated with radiation therapy. Physical examination shows severely compromised vision in the right eye. He can recognize hand motion but cannot count fingers. Funduscopic findings are shown below. Which of the following is the most likely diagnosis?

Question

A 69-year-old man comes to the emergency department with 1 hour of sudden vision loss in his right eye.  The patient has no headache, eye pain, itching, or discharge.  He has a history of coronary artery disease, type 2 diabetes mellitus, hypertension, and hyperlipidemia.  The patient was diagnosed with prostate cancer 6 months ago and treated with radiation therapy.  Physical examination shows severely compromised vision in the right eye.  He can recognize hand motion but cannot count fingers.  Funduscopic findings are shown below.  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

Explanation: 11ec2b69_c196_f925_8f63_bf6f8a49b872_MD0005_00 This patient's presentation-acute, painless monocular vision loss-suggests central retinal artery occlusion (CRAO), which usually affects patients age >60 with underlying cardiovascular risk factors. CRAO is most commonly due to carotid atherosclerosis as the central retinal artery is a branch of the ophthalmic artery, which arises from the internal carotid artery. Other etiologies include cardiac embolism, small vessel disease (eg, hypertension, diabetes), and vasculitis (eg, giant cell arteritis). Funduscopic examination usually shows diffuse ischemic retinal pallor and a cherry red spot at the macula (due to preserved circulation via posterior ciliary arteries). Evaluation includes laboratory studies to exclude giant cell arteritis (erythrocyte sedimentation rate, C-reactive protein), carotid artery imaging, and cardiac evaluation in patients with a suspected cardioembolic source. cherry red spot CRAO can cause irreversible retinal damage within 90-100 minutes. As a result, patients require urgent ophthalmology consultation and interventions to lower intraocular pressure (eg, ocular massage, anterior chamber paracentesis, intravenous acetazolamide or mannitol). Long-term management includes atherosclerotic risk factor modification (lipid-reducing and antiplatelet agents) for prevention of recurrent vascular events. Prognosis is poor in patients with severe vision loss at the time of presentation. (Choice A) Acute angle-closure glaucoma typically presents with vision loss, severe eye pain, headache, nausea, and vomiting. Patients may also report seeing light halos. Examination shows conjunctival redness and a dilated, poorly reactive pupil. Acute angle-closure glaucoma (Choice C) Central retinal vein occlusion can also present with painless, acute, or subacute monocular vision loss. Central retinal vein occlusion is usually due to nonembolic causes. Examination can show tortuous and dilated veins, diffuse hemorrhages, disk swelling, and cotton wool spots. Central retinal vein occlusion (Choice D) Macular degeneration usually presents with progressive distortion and loss of vision, primarily in the center of the visual field (central scotomas). The "dry" form can have cellular debris (drusen) accumulate between the retina and the choroid, which sometimes leads to retinal detachment. The "wet" form is more severe, with blood vessels growing up from the choroid behind the retina, which can cause retinal detachment. Macular degeneration (Choice E) Retinal detachment presents with vision loss (peripheral followed by central) and photopsia with showers of floaters. It is usually associated with trauma, previous eye surgery, aging, and severe myopia. Retinal detachment Educational objective: Central retinal artery occlusion presents with acute, painless, monocular vision loss. Funduscopy shows diffuse ischemic retinal pallor and a cherry red macula. Management includes urgent Ophthalmology consultation and measures to lower intraocular pressure. References: A review of central retinal artery occlusion: clinical presentation and management. (http://www.ncbi.nlm.nih.gov/pubmed/23470793)

A 69-Year-Old Man Comes to the Emergency Department with 1