Prognosis of Asymptomatic Ulcerating Carotid Lesions

Abstract

One hundred twenty eight cervical carotid arteriograms were twice viewed by three readers for the evaluation of atherosclerotic disease at the carotid bifurcation. Stenoses were estimated using calipers to the nearest 5% and lesions were qualitatively characterized as smooth, irregular, or ulcerated. The intraobserver correlation coefficient between estimates of percent stenosis was .94 overall and .98 for the internal carotid artery. The average intraobserver variability in estimating percent stenosis was 5.23% for all vessels and 6.04% with a standard deviation of 8.09% for the internal carotid artery. The intraob server percent agreement at a fixed stenosis is denned as the percent of the time one reader on two readings would read at least the fixed percent stenosis among cases that might be read as having the fixed percent stenosis. The intraobserver percent agreement rate for the internal carotid artery was 95.9% at > 0% stenosis, 90.4% for 50% or greater stenosis, and 96.8% for 100% stenosis (total occlusion). The interobserver correlation coefficient between readers was .92 overall and .97 for the internal carotid artery. The absolute difference in percent stenosis between readers was 7.21% for all vessels and 8.64% for the internal carotid artery with a standard deviation of 9.5%. The interobserver agreement rate for the internal carotid artery at > 0% stenosis was 93.0%, 85.4% for 50% or greater stenosis and 96.8% at 100% stenosis. The addition of oblique views had no statistical effect on estimates of percent stenosis but increased the frequency with which irregularity and ulceration were diagnosed in the internal carotid artery.

Prognosis of Patients With Transient Ischemic Attacks and Normal Angiograms

“…The distribution of patients by age and sex is detailed in Table 1. There were more females (19) than males, with a mean age of 61 years. The right hemisphere was involved 17 times, the left, 15.…”

Ulceration and carotid artery disease.

“…Kroener et al 30 found a more benign prognosis for asymptomatic ulcerated plaques with minor stenosis. In a retrospective review of 91 ulcerated plaques, only one stroke occurred in 79 patients in a mean follow-up of 36 months (range 1-7 years).…”

Asymptomatic carotid artery disease.

“…They recommended prophylactic surgery for the large ulcers. Yet in another recent retrospective study by Kroener et al, 26 76 patients with 87 asymptomatic shallow ulcers or ulcerated plaques followed over a mean of 3 years yielded only 4 TIAs overall, 1 stroke in the 55 patients with 63 small ulcers, and none in the 21 with 24 large ulcers. Based on the stroke rate of 1% over a seven year period, the authors concluded endarterectomy is not justified for asymptomatic carotid bifurcation ulcerations.…”