Search Results (3)

Background: Computed tomography perfusion (CTP)-estimated core volume is associated with functional outcomes in acute ischemic stroke. This relationship might differ among patients, depending on brain volume. Materials and Methods: We retrospectively included patients from the MR CLEAN Registry. Cerebrospinal fluid (CSF) and intracranial volume (ICV) were automatically segmented on NCCT. We defined the proportion of the ICV and total brain volume (TBV) affected by the ischemic core as ICV_core and TBV_core. Associations between the core volume, ICV_core, TBV_core, and functional outcome are reported per interquartile range (IQR). We calculated the area under the curve (AUC) to assess diagnostic accuracy. Results: In 200 patients, the median core volume was 13 (5–41) mL. Median ICV and TBV were 1377 (1283–1456) mL and 1108 (1020–1197) mL. Median ICV_core and TBV_core were 0.9 (0.4–2.8)% and 1.7 (0.5–3.6)%. Core volume (acOR per IQR 0.48 [95%CI 0.33–0.69]), ICV_core (acOR per IQR 0.50 [95%CI 0.35–0.69]), and TBV_core (acOR per IQR 0.41 95%CI 0.33–0.67]) showed a lower likelihood of achieving improved functional outcomes after 90 days. The AUC was 0.80 for the prediction of functional independence at 90 days for the CTP-estimated core volume, the ICV_core, and the TBV_core. Conclusion: Correcting the CTP-estimated core volume for the intracranial or total brain volume did not improve the association with functional outcomes in patients who underwent EVT. Full article

Background: Endovascular thrombectomy (EVT) through femoral access is difficult to perform in some patients with acute ischemic stroke due to challenging vasculature. We compared outcomes of EVT through femoral versus alternative arterial access. Methods: In this observational study, we included patients from the MR CLEAN Registry who underwent EVT for acute ischemic stroke in the anterior circulation between 2014 and 2019 in the Netherlands. Patients who underwent EVT through alternative and femoral access were matched on propensity scores in a 1:3 ratio. The primary endpoint was favorable functional outcome (modified Rankin Scale score ≤ 2) at 90 days. Secondary endpoints were early neurologic recovery, mortality, successful intracranial reperfusion and puncture related complications. Results: Of the 5197 included patients, 17 patients underwent EVT through alternative access and were matched to 48 patients who underwent EVT through femoral access. Alternative access was obtained through the common carotid artery (n = 15/17) and brachial artery (n = 2/17). Favorable functional outcome was less often observed after EVT through alternative than femoral access (18% versus 27%; aOR, 0.36; 95% CI, 0.05–2.74). The rate of successful intracranial reperfusion was higher for alternative than femoral access (88% versus 58%), although mortality (59% versus 31%) and puncture related complications (29% versus 0%) were more common after alternative access. Conclusions: EVT through alternative arterial access is rarely performed in the Netherlands and seems to be associated with worse outcomes than standard femoral access. A next step would be to compare the additional value of EVT through alternative arterial access after failure of femoral access. Full article

Thrombus volume in posterior circulation stroke (PCS) has been associated with outcome, through recanalization. Manual thrombus segmentation is impractical for large scale analysis of image characteristics. Hence, in this study we develop the first automatic method for thrombus localization and segmentation on CT in patients with PCS. In this multi-center retrospective study, 187 patients with PCS from the MR CLEAN Registry were included. We developed a convolutional neural network (CNN) that segments thrombi and restricts the volume-of-interest (VOI) to the brainstem (Polar-UNet). Furthermore, we reduced false positive localization by removing small-volume objects, referred to as volume-based removal (VBR). Polar-UNet is benchmarked against a CNN that does not restrict the VOI (BL-UNet). Performance metrics included the intra-class correlation coefficient (ICC) between automated and manually segmented thrombus volumes, the thrombus localization precision and recall, and the Dice coefficient. The majority of the thrombi were localized. Without VBR, Polar-UNet achieved a thrombus localization recall of 0.82, versus 0.78 achieved by BL-UNet. This high recall was accompanied by a low precision of 0.14 and 0.09. VBR improved precision to 0.65 and 0.56 for Polar-UNet and BL-UNet, respectively, with a small reduction in recall to 0.75 and 0.69. The Dice coefficient achieved by Polar-UNet was 0.44, versus 0.38 achieved by BL-UNet with VBR. Both methods achieved ICCs of 0.41 (95% CI: 0.27–0.54). Restricting the VOI to the brainstem improved the thrombus localization precision, recall, and segmentation overlap compared to the benchmark. VBR improved thrombus localization precision but lowered recall. Full article