Cerebral oximetry and predictors of diffusion-weighted lesions after carotid endarterectomy and stenting.

BACKGROUND AND AIMS: New ischemic brain lesions on diffusion-weighted imaging (DWI) occur frequently after carotid revascularization, yet their predictors and clinical significance remain incompletely characterized. This study aimed to determine the incidence, risk factors, and prognostic implications of diffusion-weighted imaging lesions (DWILs) following carotid endarterectomy (CEA) and carotid artery stenting (CAS), with particular emphasis on cerebral oximetry monitoring.

METHODS

This prospective, single-center cohort study enrolled 195 consecutive patients undergoing carotid revascularization between 2018 and 2021. All patients underwent pre- and post-procedural DW-MRI within 24 hours. Regional cerebral oxygen saturation was continuously monitored using INVOS™ cerebral oximetry. The primary outcome was new DWIL incidence. Secondary outcomes included 30-day stroke/death and 36-month mortality.

RESULTS

DWILs occurred in 68 patients, with higher incidence after CAS than CEA. Independent predictors included symptomatic stenosis, diabetes mellitus, intraprocedural hypotension, unstable plaque morphology, and INVOS desaturation >20%. The 30-day stroke/death rate was 2.1% with no difference between procedures. At 36 months, patients with DWILs showed a trend toward higher mortality.

CONCLUSIONS

DWILs occur in one-third of carotid revascularization patients, more frequently after CAS. Cerebral oxygen desaturation >20% represents a potentially modifiable risk factor. While predominantly asymptomatic acutely, DWILs associate with long-term mortality.