What is the main abnormality?
Acute thrombus at the top of the basilar artery, no evidence of stablished infarct.
What is the next step for this patient?
Acute occlusion of the basilar artery is a life threatening event, which carries a terrible prognosis: ~ 90% mortality depending on the location, and high morbidity in the survivors. If the patient is considered eligible, further clot retrieval treatment should be prompt offered.
The hyperdensity at the tip of the basilar artery is confirmed as a filling defect on CTA images consistent with thrombosis. Vertebral arteries and P2 segments of the posterior cerebral arteries opacify normally. Although there are resolution limitations, the superior cerebellar arteries appear to be involved.