Abstract
Posterior reversible encephalopathy syndrome (PRES) is known to present with headache, altered mental status, seizure and visual loss. It shows reversible edema in bilateral parietal, temporal, and occipital lobes on magnetic resonance imaging (MRI). Here, we present a rare case of a 69-year-old male who was diagnosed with PRES after bilateral carotid endarterectomy (CEA). Preoperative angiography revealed severe bilateral carotid artery stenosis (>85% stenosis by North American Symptomatic Carotid Endarterectomy Trial). Since the perfusion area of the left internal carotid artery was larger, we first performed left CEA uneventfully, then right CEA 2 months later. Postoperative images showed hyperperfusion in the right hemisphere without any noticeable symptoms. Deterioration of consciousness, convulsion, and left homonymous hemianopia suddenly developed in the 23rd postoperative day (POD). MRI showed edematous signal changes in the right temporal and occipital area. Despite anti-hypertensive therapy with deep sedation, MRI on POD 35 showed globally distributed edematous areas in both hemispheres. Such drastic MRI findings as well as the relevant symptoms gradually improved in the following 2 weeks. These clinically and radiographically reversible characteristics led to the diagnosis of PRES. PRES occurred during prolonged hyperperfusion state and edematous signal changes in MRI spread from the operative side to the contralateral side, suggesting that hyperperfusion after bilateral CEA contributes to inducing PRES.
