Reperfusion injury on magnetic resonance imaging after carotid revascularization.

BACKGROUND AND PURPOSE Reperfusion injury can be revealed as delayed gadolinium enhancement in the subarachnoid space on a fluid-attenuated inversion recovery image, which is designated as a hyperintense acute reperfusion marker (HARM). We sought to investigate the occurrence and predictors of HARM and its association with new ischemic infarcts after carotid revascularization. METHODS Forty-five patients who underwent carotid endarterectomy or stenting were prospectively enrolled. Diffusion-weighted imaging and fluid-attenuated inversion recovery were performed before and 24 hours after the procedures. Postprocedural fluid-attenuated inversion recovery was done after intravenous gadolinium injection. RESULTS HARM was observed in 8 (17.8%) patients. Of these, 4 patients showed neurological deterioration associated with HARM. These symptomatic HARMs disappeared on follow-up magnetic resonance imaging. Patients with symptomatic HARM were older (P=0.010) and had more frequent leukoaraiosis (P=0.012) and higher postprocedural systolic blood pressure (P=0.025) than those without. New brain infarcts on postprocedural diffusion-weighted imaging were identified in 13 (28.9%) patients. HARM was not associated with new infarcts. CONCLUSIONS HARM after carotid revascularization is not uncommon. Symptomatic HARM was associated with old age, underlying leukoaraiosis, and postprocedural high blood pressure.