Contrast Extravasation in a Patient with Right MCA Stroke Mimicking Cerebral Edema
Chellam Nayar1, Muhannad Seyam2, Fatemeh Sobhani1
1University of Vermont College of Medicine, 2UVMMC Neurology
Background:
The blood-brain barrier (BBB) helps regulate permeability, ion and nutrient balance, and brain hemodynamics. Disruption of the BBB can occur in many neurological disorders, including ischemic stroke, and increases extravasation with poorly regulated flux along the BBB.
Results:
A 77-year-old female patient underwent elective bronchoscopy complicated by a stroke code for sudden-onset left-sided weakness after the procedure. Examination was consistent with a right MCA syndrome. CT was negative for acute intracranial abnormality and CT angiogram was notable for mild stenosis of the right cavernous carotid but no large vessel occlusion. CT perfusion demonstrated mildly decreased blood flow in the right cerebral hemisphere, consistent with decreased perfusion without completed infarction in the right MCA territory. She was deemed a candidate for reperfusion therapy and received IV Tenecteplase for suspected acute ischemic stroke. Repeat CT was obtained the following day given clinical worsening, which was concerning for cerebral edema isolated to the right hemisphere without midline shift. This was not confirmed on MRI briefly afterward, which only showed subtle diffusion restriction involving the cortices of the right hemisphere without associated T2/FLAIR hyperintensity or SWI artifact. EEG and LP obtained, given unclear presentation, were reassuring. Follow-up CT the following day demonstrated marked improvement of the right hemispheric hyperdensity that was initially concerning for edema. Repeat MRI eventually demonstrated unequivocal cortical diffusion restriction with T2-hyperintense correlate in the right MCA territory most consistent with a right MCA ischemic stroke. She gradually improved and was discharged home one week after hospitalization.
Conclusions:
The overall presentation was ultimately consistent with an acute ischemic stroke involving the right MCA territory – related to periprocedural hypoperfusion in a patient with mild right carotid disease. Disruption of the BBB can occur in ischemic stroke and most likely led to contrast extravasation mimicking edema on non-contrast CT in our patient.