Accuracy of computed tomography perfusion-defined ischemic core and follow-up infarction after basilar artery thrombectomy

Chen Pengjun¹Xia Li¹Yechao Huang¹Junguo Hui²Jie Rao³Wenya Zhang¹Lijun Shang⁴Xiao Chen¹Ruijie Gao¹Jinwei Zhou¹Shuiwei Xia¹Qiao-Ling Ding^5*Jian Song Ji^1*

• ¹Zhejiang Key Laboratory of Imaging and Interventional Medicine, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Hospital of Zhejiang University, Lishui, China
• ²Zhejiang Chinese Medical University, Zhejiang Chinese Medical University, Hangzhou, China
• ³Department of Neurology, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Hospital of Zhejiang University, Lishui Central Hospital, Lishui, China
• ⁴Department of Radiology, Jinyun County People's Hospital, Lishui, China
• ⁵Affiliated Hangzhou Xixi Hospital, Zhejiang University School of Medicine, Hangzhou, China

Purpose: Accurate identification of computed tomography (CT) perfusion ischemic core in patients with basilar artery occlusion (BAO) on admission remains challenging despite its critical role in prognostic prediction and treatment decision-making. We aimed to define the optimal threshold for identifying the ischemic core by assessing agreement in lesion extent and spatial distribution using Syngo.Via. Methods: We retrospectively analyzed 91 patients with BAO who achieved successful recanalization after endovascular thrombectomy at our center. The ischemic core was estimated using the following thresholds: cerebral blood flow (CBF) < 10 or 15 mL/100 g/min by Syngo.via, cerebral blood volume < 1.2 mL/100 mL by Syngo.via, and time to maximum > 10 s by RAPID. The Posterior Circulation Alberta Stroke Program Early CT Score was used to assess the extent of the infarction. Statistical analyses included the intraclass correlation coefficient (ICC) and receiver operating characteristic analyses. Results: The CBF <10 mL/100 g/min threshold demonstrated good agreement in extent with follow-up infarction (ICC: 0.81 [95% confidence intervals 0.72–0.87]), with overestimation or underestimation the most uncommon (n = 9). For the detection of midbrain, pontine, and cerebellar infarction, this threshold yielded the best performance with the area under the curve ranging from 0.79 (midbrain, 0.66–0.93; P < 0.001) to 0.90 (pons, 0.83–0.98; P < 0.001). Conclusion: In patients with BAO after successful recanalization, the optimal threshold for the ischemic core was a CBF <10 mL/100 g/min. This threshold may serve as a reliable imaging biomarker, aiding in the prediction of tissue outcomes and treatment decision-making.