Sebastian Ekkehard Beyer, Presenter: Nothing to Disclose

Louisa von Baumgarten, Abstract Co-Author: Nothing to Disclose

Kolja Thierfelder MD, MSc, Abstract Co-Author: Nothing to Disclose

Hendrik Janssen MD, Abstract Co-Author: Nothing to Disclose

Thorsten R. C. Johnson MD, Abstract Co-Author: Nothing to Disclose

Birgit Betina Ertl-Wagner MD, Abstract Co-Author: Nothing to Disclose

Maximilian F. Reiser MD, Abstract Co-Author: Nothing to Disclose

Wieland H. Sommer MD, Abstract Co-Author: Nothing to Disclose

Recent studies in dynamic CTA assessment of collateralization of leptomeningeal vessels in the evaluation of strokes have been promising. Our aim was to evaluate the predictive value of the velocity of collateral filling for initial and follow-up lesion size.

We included all patients with an M1±ICA occlusion, that had follow-up imaging, from an existing cohort of 1791 consecutive patients who underwent multimodal CT, including whole brain CT perfusion (WB-CTP), for suspected stroke. WB-CTP raw datasets were reconstructed as dynamic angiographies. The velocity of collateral filling was quantified using the mean difference between time to peak contrast enhancement of the M2 segment distal to the occlusion compared to the contralateral M2 segment (figure). CBV and MTT-CBV mismatch were assessed in initial CTP. Follow-up lesion size was assessed by MRI or NECT. Multivariate analyses were performed to adjust for extent and origin of collateralization, additional ICA occlusion and type of treatment.

Our study comprised 116 patients. In the multivariate analysis, a fast collateral filling was an independent predictor of a small CBV lesion (p<0.001) and a large relative mismatch (p<0.001) on initial CTP, of a small follow-up lesion (p<0.001), and of a small difference between initial CBV and follow-up lesion size (p=0.024). Other independent predictors of a small lesion on follow-up were a high morphological collateral grade (p=0.001), lack of an additional ICA occlusion (p=0.009), and IV thrombolysis (p=0.022).

Fast filling of collateral vessels predicts initial CTP and follow-up lesion size and is independent of the extent of collateralization. The independent association with the CBV-follow-up difference indicates a role in the process of penumbral loss and may help to select treatment.

Time-resolved dynamic CT angiography allows to assess the velocity of collateral filling which adds important functional information about collateralization.

Beyer, S, von Baumgarten, L, Thierfelder, K, Janssen, H, Johnson, T, Ertl-Wagner, B, Reiser, M, Sommer, W, The Velocity of Collateral Filling as Determined by Dynamic CT-Angiography Predicts Initial and Final Infarct Size in Patients with Acute Ischemic Stroke.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14015403.html