The Pattern of Leptomeningeal Collaterals on CT Angiography Is a Strong Predictor of Long-Term Functional Outcome in Stroke Patients With Large Vessel Intracranial Occlusion

Abstract

Background and purpose The role of non-invasive methods in the evaluation of collateral circulation has yet to be defined. We hypothesized that a favorable pattern of leptomeningeal collaterals, as identified by computed tomography angiography (CTA), correlates with improved outcomes. Methods Data from a prospective cohort study at two university based hospitals where CTA was systematically performed in the acute phase of ischemic stroke were analyzed. Patients with complete occlusion of the intracranial internal carotid artery (ICA) and/or the middle cerebral artery (MCA-M1 or M2 segments) were selected. Leptomeningeal collateral pattern was graded as a three category ordinal variable (less, equal, or greater than the unaffected contralateral hemisphere). Univariate and multivariate analyses were performed to define the independent predictors of good outcome at 6 months (mRS≤2). Results 196 patients were selected. The mean age was 69 ±17 years and the median NIHSS score was 13 (IQR 6-17). In the univariate analysis, age, baseline NIHSS, pre-stroke mRS, ASPECT score, admission blood glucose, history of hypertension, coronary artery disease, congestive heart failure, atrial fibrillation, site of occlusion, and collateral pattern were predictors of outcome. In the multivariate analysis, age (OR 0.95; 95%CI [0.93-0.98], p=0.001), baseline NIHSS (OR 0.75; [0.69-0.83], p<0.001), pre-stroke mRS (OR 0.41; [0.22-0.76], p=0.01), intravenous r-tPA (OR 4.92; [1.83-13.25], p=0.01), diabetes( OR 0.31; [0.01-0.98], p=0.046) and leptomeningeal collaterals (OR 1.93; [1.06-3.34], p=0.03) were identified as independent predictors of good outcome. Conclusion Consistent with angiographic studies, leptomeningeal collaterals on CTA are also a reliable marker of good outcome in ischemic stroke.

Effect of the Interaction between Recanalization and Collateral Circulation on Functional Outcome in Acute Ischaemic Stroke

“…We did not find any association between the extent of collateral circulation and other baseline features of the population in study. In particular, the distribution of CCS was not influenced by age, hypertension or other vascular risk factors 13 , differently from previous reports [14][15][16][17] . Nor was the distribution of the collateral circulation influenced by the time of ischaemia, and that could be explained if we consider that the presence of collaterals mainly depends on individual pre-existing anatomy.…”

Proximal flow to middle cerebral artery is associated with higher thrombus density in terminal internal carotid artery occlusion

“…Such a proximal collateral flow was present in 21% and the rate was in the range of a previous study (12%) 10. The relevance of proximal and pial (distal) collaterals for clinical outcome in acute stroke is already established 11. Most importantly, we detected more hyperdense clots and a higher frequency of leptomeningeal collaterals in patients with proximal collateral flow to the MCA.…”

“…Two examples are shown in Figure 2, Panel A. We used a visual scale to assess the status of leptomeningeal collateralization on CTA 11. Briefly, the leptomeningeal collateral pattern was graded by using a three‐category ordinal variable (absent, less, or equal to the unaffected contralateral hemisphere).…”

Collateral state and the effect of endovascular reperfusion therapy on clinical outcome in ischemic stroke patients

“…2009; Lima et al. 2010) on clinical outcome. Others looked at the interaction of reperfusion and collaterals on final outcome in acute stroke patients treated with both IVT (Miteff et al.…”