Angiographic perfusion imaging: Real-time assessment of endovascular treatment for cerebral vasospasm

BACKGROUND AND PURPOSE: Cerebral perfusion analysis is useful in the diagnosis and treatment of cerebral vasospasm. A new modality of real-time cerebral perfusion imaging and analysis has been developed using standard 2-dimensional angiography. We report our initial experience with this technique to assess response to therapy during endovascular vasospasm procedures. METHODS: Colorized angiographic perfusion maps were obtained immediately before and after endovascular vasospasm treatment. Semiquantitative perfusion parameters (cerebral blood flow, cerebral blood volume, mean transit time, and time to peak) were calculated from time-density curves obtained from intraarterial contrast injection. The effects of intraarterial vasospasm therapy were assessed. RESULTS: Eight vascular territories in 4 patients with vasospasm underwent interventional angiography and angiographic perfusion analysis. Pretreatment perfusion maps demonstrated variable perfusion deficits in specific vascular territories. After endovascular treatment in 6 vessels, improvement was seen to varying degrees in both angiographic appearance and perfusion parameters. Clinical improvement and reduction in transcranial Doppler velocity was also observed. CONCLUSIONS: Real-time angiographic perfusion imaging is feasible during endovascular procedures for vasospasm. Perfusion analysis may aid in assessment of efficacy of the intervention. Comparison with traditional perfusion imaging is needed to validate this technique.