Objective: To evaluate the correlation between microembolism (ME) and incidence of silent brain infarcts during carotid endarterectomy.
Materials and methods: Patients were assessed using transcranial Doppler, carotid ultrasound and pre- and postoperative magnetic resonance imaging (MRIs). The clinical status, need for shunt insertion and significant decrease in the blood flow in the middle cerebral artery were recorded. All data were analysed using multivariate regression models.
Results: Out of the 76 patients examined, 17 (22%) had new postoperative lesions seen on MRI. Three of them (4%) were symptomatic, 14 (18%) were asymptomatic. The multivariate regression models showed that ME is a potent predictor of "silent" ischemic brain lesions, at p<0.001 (OR [95% CI]-1.1 [1.05, 1.2]). Digital plaque texture analysis predicted ME (p=0.028; OR [95% CI]-0.32 [0.12, 0.89]). The risk of ME increases steadily with the decrease in the echogenicity of the plaque.
Conclusions: ME is a potent predictor of "silent" ischemic brain lesions among patients with carotid stenosis. An analysis of plaque texture can predict the degree of ME during endarterectomy and is more precise than the standard GSM.