Teaching NeuroImage: Rapidly Changing Symptoms With Multistep Migration of Clot in the Posterior Circulation After Tenecteplase for Acute Ischemic Stroke.

A 70-year-old man presented with acute vertigo and ataxia. CT angiogram revealed left V3 segment vertebral artery occlusion (Figure 1, A and B). He received tenecteplase (0.25 mg/kg IV bolus) and was transferred to our comprehensive stroke center due to the risk of early neurologic deterioration from clot migration that would necessitate thrombectomy. Repeat CT angiogram revealed migration to V4 segment with posterior inferior cerebellar artery reopacification and improving symptoms (Figure 1, C and D). Two hours post-tenecteplase, he developed aphasia, right hemianopia, and sensorimotor symptoms (National Institutes of Health Stroke Scale 15). Angiogram showed a left P1 posterior cerebral artery thrombus. Attempted thrombectomy resulted in further migration to P2. MRI demonstrated multiple infarcts (Figure 2), representing stepwise ischemia from dynamic clot movement. Clot reformation from hypercoagulability or re-embolization seemed unlikely, given short time course and exclusive posterior circulation involvement.