Kevin O’Connor, MD
Visser MJ, Yang JYM, Calamante F, Kean M, Adamson CL, Sharma G, Anderson V, Campbell BCV, Mackay MT. Automated Perfusion-Diffusion Magnetic Resonance Imaging in Childhood Arterial Ischemic Stroke. Stroke. 2021.
Visser et al. explore the feasibility of automated software to evaluate MRI perfusion-diffusion mismatch in children with acute ischemic stroke. Their retrospective study examined 29 children with acute ischemic stroke and MR perfusion imaging obtained within 72 hours of symptom onset at a single center. They excluded 158 children, predominantly for lack of perfusion imaging, among other reasons.
Perfusion-diffusion mismatch assessment was automated with RAPID software. The software detected an ischemic core in 19 children (66%). The remaining children (n=10, 34%) tended to present later (undetected onset-to-imaging time median 21.8 hours, IQR, 14.3–27 versus detected onset-to-imaging time median 11 hours, IQR, 7.2–23.5) and have smaller ischemic lesions (undetected core volume median 2.7 mL, IQR, 1.1–6.2 versus detected core volume median 17.3 mL, IQR, 12.4–49.6) that limited the software’s effectiveness. Eighteen of the 29 children required sedation, and they tended to be younger (median age 4.4, IQR, 2.8–7.3 versus median age 14.8, IQR, 10.7–15.7).
Of the 29 children with acute ischemic stroke, 12 had angiography consistent with vascular occlusion (ICA/M1, n=5; M2, n=5; posterior circulation, n=2). Five of the 29 children had inadequate contrast bolus administration for RAPID analysis. Most of the remaining children (21/24) did not have detected mismatch as they may have completed their strokes or reestablished perfusion by the time they were imaged. Three children (3 of 24) had perfusion-diffusion mismatch on imaging, and all had vessel occlusions. The overall median time from symptom onset to imaging was 13.7 hours (IQR, 7.5-25.3); the three mismatch patients underwent imaging at 3.75, 11, and 23.5 hours post-symptom onset.
The approach to the triage and management of pediatric acute ischemic stroke continues to evolve. Automated software such as RAPID may help identify perfusion-diffusion mismatch in pediatric patients that could prompt an acute intervention such as chemical thrombolysis or endovascular mechanical thrombectomy. Further study is needed to optimize imaging technology and protocols across institutions to better recognize and select pediatric stroke patients for acute treatment options. Additionally, younger pediatric patients need sedation more often than older and adult counterparts, which may limit the utilization of RAPID and similar software with MR imaging.