A 50-year-old woman with type 2 diabetes mellitus, hypertension, and obesity comes to the emergency department with left-sided vision loss that started 45 minutes ago. She has no fever, headache, eye pain, or tearing. On examination, she can only see hand motion with her left eye and cannot count fingers. Visual acuity in the right eye is normal. Funduscopic findings are shown below. Which of the following is the most likely cause of this patient's condition?

Question

A 50-year-old woman with type 2 diabetes mellitus, hypertension, and obesity comes to the emergency department with left-sided vision loss that started 45 minutes ago.  She has no fever, headache, eye pain, or tearing.  On examination, she can only see hand motion with her left eye and cannot count fingers.  Visual acuity in the right eye is normal.  Funduscopic findings are shown below.  Which of the following is the most likely cause of this patient's condition?

Quizplus · Accepted Answer

Explanation: 11ec2b69_c196_83f3_8f63_cfcc4d69efd3_MD0005_00 This patient with cardiovascular risk factors and acute visual loss likely has central retinal artery occlusion (CRAO). The most common cause of CRAO is carotid artery atherosclerosis. Other less frequent etiologies include cardiogenic embolism, clotting disorders, carotid artery dissection, and vasculitis (eg, giant cell arteritis). CRAO is characterized by acute-onset, painless, monocular vision loss. Patients may lose the ability to make fine distinctions (eg, finger counting), but can frequently identify objects (eg, hands). Typical examination findings include an afferent pupillary defect and funduscopy showing a pale, ischemic fundus with a "cherry red spot". Initial management should include measures to reduce intraocular pressure (eg, ocular massage, acetazolamide) and urgent ophthalmology consultation to avoid irreversible visual loss. "cherry red spot" (Choice B) Elevated intracranial pressure from tumor or idiopathic intracranial hypertension (pseudotumor cerebri) can cause visual impairment. However, this patient's lack of headache and absence of papilledema on funduscopy make the diagnosis less likely. (Choice C) Acute angle-closure glaucoma can present with acute monocular visual loss; however, it is usually associated with eye pain, headache, nausea/vomiting, and conjunctival erythema. Also, angle-closure glaucoma would not explain this patient's funduscopic findings. Acute angle-closure glaucoma (Choice D) Optic neuritis typically causes subacute (hours to days) monocular vision loss associated with eye pain that worsens with eye movement. Patients can have an afferent pupillary defect, but funduscopy characteristically shows optic disc edema. optic disc edema (Choice E) Proliferative retinopathy due to diabetes mellitus typically results in progressive visual loss in its late stages. Acute visual loss may take place in the setting of a complication such as vitreous hemorrhage; however, this patient does not have evidence of neovascularization or hemorrhage on funduscopy, making the diagnosis unlikely. Proliferative retinopathy Educational objective: Central retinal artery occlusion is most commonly caused by carotid artery atherosclerosis and presents with acute, painless, monocular vision loss. Patients typically have an afferent pupillary defect on examination and funduscopy may show a pale, ischemic fundus with a "cherry red spot." References: A review of central retinal artery occlusion: clinical presentation and management. (http://www.ncbi.nlm.nih.gov/pubmed/23470793) Ocular emergencies. (http://www.ncbi.nlm.nih.gov/pubmed/17910297)

A 50-Year-Old Woman with Type 2 Diabetes Mellitus, Hypertension, and Obesity