A 75-year-old female, with a history of hypertension, was last seen normal at noon. She was subsequently found to be aphasic with a right hemiplegia and taken to a local hospital where intravenous tPA was administered at 14:30h. She was transferred to an endovascular center where she was noted to have persistent aphasia and hemiplegia. In addition, she did not blink to threat in the left visual field.
Her NIH Stroke Scale Score was 19.
She was imaged at the endovascular center at 17:30h. A proximal left M1 occlusion and right PCA occlusion was seen on CT angiography. The RAPID mismatch map (shown above) demonstrates a matched lesion in the right posterior cerebral artery territory and a large region of mismatch in the left middle cerebral artery territory.
The RAPID image columns show very low CBF in the right posterior cerebral artery (PCA) territory (dark blue area shown with white arrow) as well as a region of CBF reduction in the left middle cerebral artery (MCA) territory. Note that the cerebral blood flow volume is preserved in the left MCA territory but is substantially reduced in the right PCA territory. Some mild hypodensity is present in the basal ganglia on the non-contrast CT.
What do you recommend?No endovascular intervention
The patient had complete recovery of her language function and substantial improvement in her strength. She had persistent left visual field cut. A follow-up CT and MRI revealed a right PCA infarct and a smaller patchy infarct in the left basal ganglia and centrum semiovale. The infarcted regions corresponded with the areas of severe CBF reduction on the baseline RAPID map (shown in pink on the top middle panel). The left MCA cortical regions were normal.
The patient suffered two embolic strokes at approximately the same time; one in the anterior circulation and one in the posterior circulation. Reperfusion was performed for the anterior circulation lesion that had a large mismatch.
The patient was discharged on a cardiac monitor to look for evidence of paroxysmal atrial fibrillation, which could account for embolism to multiple vascular territories.