1. Vivek Kalra, MD Balaji Rao, MD Ajay Malhotra, MD
Teaching NeuroImages: Altered Mental Status Following Carotid Revascularization
Vivek Kalra, MD
Balaji Rao, MD
Ajay Malhotra, MD

2. Vignette
69 year-old male presents with hypertensive crisis manifest by acute-onset confusion and elevated systolic pressures to the 160s
He underwent carotid endarterectomy one day earlier for 75% proximal internal carotid artery stenosis
Stenosis was discovered after he developed right facial droop from multiple embolic infarcts in the left middle cerebral artery distribution two weeks earlier
Kalra et al

3. Imaging A B C D rCBF rCBV MTT Kalra et al
CT perfusion performed one day following left carotid endarterectomy shows left middle cerebral artery distribution increased relative cerebral blood flow (Figure,A) increased relative cerebral blood volume (Figure,B), and decreased mean transit time (Figure,C) – findings are consistent with cerebral hyperfusion syndrome following revacularization. Non-contrast CT shows no hemorrhage or edema (Figure,D).
rCBF
rCBV
MTT
Kalra et al

4. Perfusion Imaging of Cerebral Hyperperfusion Syndrome Following Revascularization
Cerebral Hyperperfusion Syndrome (CHS) following revascularization may present as ipsilateral headache, focal seizure, and/or neurological deficit
CHS is caused by loss of autoregulation, hypertension, and ischemia-reperfusion injury resulting in increased regional blood flow and vascular congestion
Non-perfusion imaging may show intraparenchymal hemorrhage or edema
Perfusion imaging shows increased relative blood flow, increased relative blood volume, and decreased mean transit time
Labetalol and clonidine are used for aggressive blood pressure control until cerebral autoregulation is restored
Adhiyaman V, Alexander S. Cerebral hyperperfusion syndrome following carotid endarterectomy. QJM Apr;100(4):
van Mook WN, Rennenberg RJ, Schurink GW, van Oostenbrugge RJ, Mess WH, Hofman PA, de Leeuw PW. Cerebral hyperperfusion syndrome. Lancet Neurol Dec;4(12):
Kalra et al