A novel cerebral small vessel disease burden score including brain atrophy predicts collateral status in ischemic stroke treated with thrombectomy

Background and aims: Cerebral small vessel disease (cSVD) could impact collateral efficiency. This study had the objective to evaluate whether the total cSVD burden including brain atrophy is associated with the ability to recruit collaterals in acute ischemic stroke (AIS). Methods: This retrospective study included consecutive adult patients with AIS admitted to the Sapienza University of Rome teaching hospital in 2023 and treated with mechanical thrombectomy (MT) (alone or combined with IV thrombolysis). STRIVE criteria were followed to assess the cSVD signs on MRI. A novel modified cSVD burden score was constructed by adding brain atrophy (measured by the Pasquier’s scale) to the standard score. Collateral status was evaluated by the adapted American Society of Interventional and Therapeutic Radiology/Society of Interventional Radiology (ASITN/SIR) score on pre-treatment CT-Angiography dichotomized into good (3-4) versus poor (0-2). Results: Overall, 80 patients (51.2% females; mean[SD] age of 73.1[13.8] years) were eligible for analysis; 44(55%) patients had poor collaterals and 41(51.2%) patients had any cSVD sign. Multivariate analysis showed that, conversely to standard cSVD score, a moderate to severe modified total cSVD burden score resulted an independent predictor of poor collateral status (OR adjusted for age 3.733, 95%CI 1.462-9.535, p=0.006; OR adjusted for cSVD risk factors and baseline NIHSS 4.905, 95%CI 1.657- 14.515, p=0.004;AUC significantly improved by 20%). Conclusions: Our study showed that brain atrophy as additional radiological sign of cSVD and index of brain frailty could have a significant role in improving prediction of leptomeningeal collateral recruitment potential in AIS patients treated with MT.