Richard Aviv
Collateral status is recognized as fundamentally important in patient selection and outcome determination in acute stroke. Yet, there were until recently a paucity of larger studies examining its effect in the presence of recanalization and common complications in stroke therapy such as hemorrhagic transformation. We wanted to tease out these elements with the intent of quantifying the contribution of collaterals to these different features.
In light of recent endovascular studies such as Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke (ESCAPE),1 we are even more focused on collaterals and their effect on outcome. We are particularly interested in the timing of CTA and the appearance of collaterals and the role of dynamic CTA derived from CTP raw data.
We have had a number of emails from interested researchers to discuss our views of collateral assessment in the absence of multiphase CTA. We remain confident in our ability using the 64-section CT system employed in our study. This would certainly change with faster scanners with a greater number of detectors.
We believe collaterals are not a binary process and a better understanding of spatial distribution might refine infarct prediction models.
Our new data will be presented at the Canadian Stroke Congress meeting in Quebec this month.
Reference
- Goyal M, Demchuk AM, Menon BK, et al; ESCAPE Trial Investigators. Randomized assessment of rapid endovascular treatment of ischemic stroke. N Engl J Med 2015; 372:1019–30. doi: 10.1056/NEJMoa1414905