Journal of Neuro-Ophthalmology, December 2005, Volume 25, Issue 4

Carotid Endarterectomy for Ophthalmic Manifestations

Carotid End arte recto my for Ophthalmic Manifestations: What Do We Do? David Nicolle, MD, and Vladimir Hachinski, MD I n the use ofcarotidendarterectomy ( CE), the Department surgery. Carotid stenting may be offered if there are of Clinical Neurological Sciences in London, Ontario, significant medical problems precluding CE. follows the guidelines derived from the North American If there is 50%- 70% stenosis of the internal carotid Symptomatic Carotid Endarterectomy Trial ( 1), which was artery, CE is performed only in men who have also suffered organized at our institution. one or more hemispheric transient ischemic attacks, par- In our hospital, three surgeons perform between 100 ticularly if the transient ocular ischemic attack has occurred and 110 CEs and between 10 and 20 cervical carotid stents within 48 hours. In the 50%- 70% stenosis group, less each year. Most patients are referred from the southwestern benefit has been shown for women, and surgery is seldom Ontario region. Our complication rate for CE is 1% for recommended. If there is less than 50% internal carotid death and 1% for major stroke. artery stenosis, we do not perform CE. This is how we currently manage patients with the 2) Central retinal artery occlusion ( CRAO): This four major ophthalmic indications for CE: condition is also initially evaluated with carotid ultrasound 1) Transient monocular visual loss ( TMVL): These and TEE, as well as a sedimentation rate ( to exclude tem-patients undergo carotid Doppler ultrasound and trans- poral arteritis). Management guidelines for CE are the esophageal echocardiography ( TEE). TEE is preferred over same as for TMVL. transthoracic echocardiography because TEE allows a better 3) Asymptomatic Hollenhorst plaque ( cholesterol look not only at the left atrium, but also the ascending aorta, retinal emboli): CE is not performed, irrespective of the which is often an unrecognized source of emboli. If the degree of internal carotid artery stenosis. Such patients carotid ultrasound shows hemodynamically significant ste- undergo TEE to exclude a cardiac or aortic source of nosis, the next step would be cerebral angiography. More emboli and a carotid ultrasound if the TEE is negative. We recently, contrast- enhanced magnetic resonance angiography do not operate on these asymptomatic patients because the ( MRA) and computed tomographic angiography ( CTA) have stroke rate is very low and there is no difference between been used with increasing frequency. The reason for this shift medical treatment and CE. is that MRA and CTA are less dangerous because they do not 4) Ocular ischemic syndrome ( OIS): Patients with involve catheterization and are also cheaper and quicker. OIS typically have severe internal carotid artery stenosis or If the echocardiogram test shows a plausible source complete occlusion. Those with more than 70% stenosis are of emboli, the patient would be anticoagulated with warfarin. offered CE because it may help in stopping the progression Eighty- one milligrams of aspirin per day may be added if of the ocular ischemia. CE is not offered for total carotid atherosclerotic carotid arteries were also found, although artery occlusion because the success rate of opening the this increases the risk of bleeding and must be individualized. artery in an occlusion is low and there is a high compli- If the internal carotid artery shows more than 70% cation rate of stroke, stenosis, CE is offered to the patient. If a cardiac or aortic source has been found by echocardiography and the patient Acknowledgment has been anticoagulated, the anticoagulation would be The authors gratefully acknowledge the help of stopped to do the CE and then started up again after the Dr. Don Lee and Dr. Gary Ferguson. Department of Ophthalmology ( DN), University of Western Ontario, REFERENCES London, Ontario, Canada; and Department of Clinical Neurological , ,-, „ TTT . . ,, TTT, _ . . . . . _ _ . „ ., ' r ° 1. Barnett HJ, Meldrum Hb, bliasziw M. 1 he appropriate use ot carotid Sciences ( VH), University of Western Ontario, London, Ontario, Canada. endarterectomy. Can Med Assoc J 2002; 166: 1169- 79. Address correspondence to David A. Nicolle, MD, University 2. Benavente O, Eliasziw M, Streifler JY, et al. Prognosis after transient Hospital, Neuro- Ophthalmology Unit, 339 Windermere Road, London, monocular blindness associated with carotid- artery stenosis. N Engl ON N6A 5A5, Canada; E- mail: David. Nicolle@ lhsc. on. ca J Med 2001; 345: 1084- 90.