Characteristic sonographic findings of early restenosis after carotid endarterectomy.
OBJECTIVE
Restenosis of the carotid artery after carotid endarterectomy (CEA) is a major complication. The frequency, time of occurrence, and tissue characteristics of carotid restenosis were assessed with sonography.


METHODS
Two hundred sixteen patients who had CEA for carotid stenosis were studied; follow-up sonography and magnetic resonance angiography were done 2 weeks, 3 months, and then every year after CEA. On sonography, restenosis was defined as an internal carotid artery (ICA) with a peak systolic velocity of 170 cm/s or greater or a maximum area of stenosis of 90% or greater.


RESULTS
During 605 artery-years of follow-up, 18 patients (7.5%) were found to have restenosis on sonography: 4 at 3 months, 11 at 1 year, and 3 at 2 years after CEA. At the time that restenosis was detected, in all 18 ICAs the peak systolic velocity exceeded 200 cm/s and had more than doubled since the last measurement (mean +/- SD, 103 +/- 27 to 321 +/-107 cm/s), whereas the area of stenosis exceeded 90% in 6 patients, and magnetic resonance angiography revealed stenosis of 60% or greater in 8 patients. On sonography, all of the restenotic plaques were isoechoic and concentric. The restenosis was asymptomatic in 17 patients. Vascular risk factors or the severity of initial carotid stenosis before CEA were not associated with development of restenosis. Eleven patients had successful endovascular therapy, and the others received medical treatment.


CONCLUSIONS
A marked increase in the flow velocity through an operated ICA is a good indication of restenosis. The isoechogenicity and concentricity of the restenotic plaques suggest that the restenosis is primarily the result of intimal hyperplasia.
Makihara
Noriko
N
Department of Cerebrovascular Disease, Cerebrovascular Center and Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan.
Toyoda
Kazunori
K
Uda
Ken
K
Inoue
Tooru
T
Gotoh
Seiji
S
Fujimoto
Shigeru
S
Yasumori
Kotaro
K
Ibayashi
Setsuro
S
Iida
Mitsuo
M
Okada
Yasushi
Y
D000368:Aged; D016893:Carotid Stenosis / Q000453:epidemiology* / Q000601:surgery*; D015897:Comorbidity; D016894:Endarterectomy, Carotid / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D011183:Postoperative Complications / Q000453:epidemiology*; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D016896:Treatment Outcome