Tissue Protrusion With Attenuation Is Associated With Ischemic Brain Lesions After Carotid Artery Stenting

Background and Purpose— Tissue protrusion between stent struts is frequently observed on optical frequency domain imaging evaluation after carotid artery stenting, but its clinical relevance is unclear. We aimed to investigate the association between the characteristics of tissue protrusion assessed by optical frequency domain imaging and brain lesions identified by diffusion-weighted imaging after carotid artery stenting. Methods— Sixty-five consecutive patients who underwent optical frequency domain imaging after protected carotid artery stenting were enrolled in the study. Cross-sectional optical frequency domain images within the stented segments were evaluated at 0.125-mm intervals. Magnetic resonance imaging was performed 1 to 10 days after treatment. The characteristics of tissue protrusion were compared between patients with and without new ipsilateral brain lesions on posttreatment magnetic resonance imaging. Results— Tissue protrusion was observed in 62 patients (95%). New brain lesions were observed in 24 patients (37%). In the multivariate analysis, the presence of protrusion with attenuation (odds ratio, 2.94 [95% CI, 1.05–8.68]P =0.04) was associated with new brain lesions after carotid artery stenting.Conclusions— The presence of protrusion with attenuation assessed by optical frequency domain imaging was associated with ipsilateral brain lesions after carotid artery stenting. Prevention or treatment of protrusions with attenuation may reduce ischemic brain lesions after carotid artery stenting.