Mujanovic Adnan, Windecker Daniel, Serrallach Bettina L, Kurmann Christoph C, Almiri William, Meinel Thomas R, Seiffge David J, Piechowiak Eike I, Dobrocky Tomas, Gralla Jan, Fischer Urs, Dorn Franziska, Chapot René, Pilgram-Pastor Sara, Kaesmacher Johannes
Department of Diagnostic and Interventional Neuroradiology, Inselspital University Hospital Bern, University of Bern, Bern, Switzerland.
Graduate School of Health Sciences, University of Bern, Bern, Switzerland.
J Neurointerv Surg. 2024 Dec 26;17(e1):e47-e54. doi: 10.1136/jnis-2023-021218.
Immediate non-contrast post-interventional flat-panel detector CT (FPDCT) has been suggested as an imaging tool to assess complications after endovascular therapy (EVT). We systematically investigated a new imaging finding of focal hyperdensities correlating with remaining distal vessel occlusion after EVT.
A single-center retrospective analysis was conducted for all acute ischemic stroke patients admitted between July 2020 and December 2022 who underwent EVT and immediate post-interventional FPDCT. A blinded core lab performed reperfusion grading on post-interventional digital subtraction angiography (DSA) images and evaluated focal hyperdensities on FPDCT (here called the distal occlusion tracker (DOT) sign). DOT sign was defined as a tubular or punctiform, vessel confined, hyperdense signal within the initial occlusion target territory. We assessed sensitivity and specificity of the DOT sign when compared with DSA findings.
The median age of the cohort (n=215) was 74 years (IQR 63-82) and 58.6% were male. The DOT sign was positive in half of the cohort (51%, 110/215). The DOT sign had high specificity (85%, 95% CI 72% to 93%), but only moderate sensitivity (63%, 95% CI 55% to 70%) for detection of residual vessel occlusions. In comparison to the core lab, operators overestimated complete reperfusion in a quarter of the entire cohort (25%, 53/215). In more than half of these cases (53%, 28/53) there was a positive DOT sign, which could have mitigated this overestimation.
The DOT sign appears to be a frequent finding on immediate post-interventional FPDCT. It correlates strongly with incomplete reperfusion and indicates residual distal vessel occlusions. In the future, it may be used to complement grading of reperfusion success and may help mitigating overestimation of reperfusion in the acute setting.
介入后即刻非增强平板探测器CT（FPDCT）已被推荐作为评估血管内治疗（EVT）后并发症的成像工具。我们系统地研究了一种新的成像发现，即与EVT后残留的远端血管闭塞相关的局灶性高密度影。
对2020年7月至2022年12月期间收治的所有接受EVT及介入后即刻FPDCT的急性缺血性卒中患者进行单中心回顾性分析。一个盲法核心实验室对介入后数字减影血管造影（DSA）图像进行再灌注分级，并评估FPDCT上的局灶性高密度影（此处称为远端闭塞追踪器（DOT）征）。DOT征定义为初始闭塞目标区域内的管状或点状、局限于血管内的高密度信号。我们将DOT征与DSA结果进行比较，评估其敏感性和特异性。
该队列（n = 215）的中位年龄为74岁（四分位间距63 - 82岁），男性占58.6%。该队列中有一半（51%，110/215）的患者DOT征呈阳性。DOT征具有较高的特异性（85%，95%可信区间72%至93%），但检测残留血管闭塞的敏感性仅为中等（63%，95%可信区间55%至70%）。与核心实验室相比，操作人员在整个队列的四分之一（25%，53/215）中高估了完全再灌注情况。在这些病例中，超过一半（53%，28/53）存在阳性DOT征，这可能减轻了这种高估。
DOT征似乎是介入后即刻FPDCT上的常见表现。它与再灌注不完全密切相关，提示残留远端血管闭塞。未来，它可用于补充再灌注成功的分级，并可能有助于减轻急性情况下对再灌注的高估。
