Information for Students and Residents » Case Study - November 2002
History
79 YO WM with acute loss of vision in the right eye while eating breakfast. He reported having previous episodes of blurred vision in the same eye lasting 30 minutes followed by a headache. The last event was 2 weeks prior to presentation. He has had no jaw claudication, scalp tenderness, shoulder weakness or weight loss. He had no complaints in the left eye.
Medical History
Hypertension, controlled with medications
Colon cancer, treated surgically
Prostate cancer, treated with external radiation
Examination
Pulse was 60, BP: 110/65 mmHg
Vision: OD: Hand motion, OS: 20/20
Pupils: Positive for 2+ Afferent Papillary Defect (APD)
Motility: Full OU
Intraocular pressures: Normal OU
Slit lamp examination: Normal anterior segments OU
Fundus Examination:
OD: Figure 1-A
OS: Figure 1-B
Figure 1-A: Color photo of the right fundus showing diffuse retinal whitening with the classic cherry-red spot. Note the abnormal blood flow in the arterioles
Figure 1-B: color photo of the normal left fundus
Ancillary Tests
Fluorescein Angiogram:
OD: Figure 2-A, B, C and D
OS: Normal
Fig 2-A
Fig 2-B
Fig 2-C
Fig 2-D
Figure 2: A, B, and C Early to mid stages of the fluorescein angiogram showing significant delay in the vascular filling. D, late phase of the angiogram.
Labs
Westergren ESR: 17
C-reactive protein: 0.09
ANA: Negative
RF: Negative
RPR: Negative
gb/Hct: 11.8/35.5
Diagnosis
Central Retinal Artery Occlusion (CRAO)
Occlusion of the central retinal artery is a condition that usually affects older patients. It typically results from a small emboli originating from the atherosclerotic carotid artery or from the heart. Occasionally, it may be related to temporal arteritis. In younger patient, other conditions that can induce thrombosis and vasculitis should be investigated.
Symptoms: Patients usually present with acute severe painless vision loss in one eye. Patients may report previous episodes of transient visual loss that lasted minutes then resolved. Symptoms of temporal arteritis usually need to be probed since patients rarely volunteer them.
Signs: Visual acuity is severely decreased to the level of 20/400 or light perception except in the presence of a cilio-retinal artery. A central retinal artery occlusion will not cause vision to be no light perception (NLP) unless the occlusion is at the level of the ophthalmic artery. The retina looks white and edematous. This allows for the underlying choroidal circulation to stand out more in the foveal center where the retina is very thin giving the classic cherry-red spot appearance.
Diagnosis: The typical presentation along with the characteristic fundus findings are sufficient to make the diagnosis. Fluorescein angiogram may demonstrate delayed filling of the retinal arterioles. The test may be normal by the time the patient presents for evaluation.
Treatment: is aimed at minimizing the damage of the retina in the acute phase and preventing late complications. Attempts at dislodging the embolus include lowering the introcular pressure by performing an anterior chamber paracentesis or ocular massage; or dilating the retinal arterioles by asking the patient to breath in a paper bag or carbogen. Results of these treatment options are variable but probably worth doing given the low side effect rate. If neovascularization of the iris or angle are noted, PRP should be initiated immediately. Medical treatment of any underlying system disease is also indicated.
Work-up: Elderly patients with CRAO should be always asked about symptoms suggestive of temporal arteritis and an ESR obtained if the index of suspension is high. A carotid Doppler and an echocardiogram should be performed if a retinal embolus is seen. Younger patients presenting with this condition should be evaluated for systemic conditions that result in hypercoagulable state and also collagen vascular diseases.
Follow up
Our patient had an anterior chamber paracentesis and asked to breath in a paper bag. Vision could not be improved despite these efforts. A carotid Doppler was positive for significant stenosis. Echocardiogram was normal.
