Reversible cerebral hyperperfusion syndrome after stenting of the carotid artery - two case reports.

Hyperperfusion syndrome can complicate carotid revascularization, be it endarterectomy or carotid artery stenting (CAS). Although extensive effort has been devoted to reducing the incidence of ischemic stroke complicating CAS, little is known about the incidence, etiology, and prevention strategies for hyperperfusion following CAS. We report two cases (female patients 72 and 81 years) presenting severe internal carotid stenosis (> 90%), who underwent presurgical and therapeutic intervention with CAS. Both patients developed hyperperfusion symptoms at 2 hours and at 30 minutes, respectively, following stenting, in both cases unilateral hyperperfusion was CCT confirmed. Case 1 was presenting with acute edema of the right hemisphere, case 2 with distended focal edema (left fronto-temporoparietally). Hyperperfusion syndrome and neurological symptoms retroceded in both cases (conservative therapy) and both patients returned to full activity (case 2 within 48 hours).