Neural Analytics, Inc., 2440 S. Sepulveda Blvd. Suite 115, Los Angeles, CA, 90064, USA.
Cardiac Biomechanics Group, University of Virginia, Charlottesville, VA, USA.
Transl Stroke Res. 2019 Oct;10(5):475-484. doi: 10.1007/s12975-018-0667-2. Epub 2018 Oct 6.
Despite being a conveniently portable technology for stroke assessment, Transcranial Doppler ultrasound (TCD) remains widely underutilized due to complex training requirements necessary to reliably obtain and interpret cerebral blood flow velocity (CBFV) waveforms. The validation of objective TCD metrics for large vessel occlusion (LVO) represents a first critical step toward enabling use by less formally trained personnel. In this work, we assess the diagnostic utility, relative to current standard CT angiography (CTA), of a novel TCD-derived biomarker for detecting LVO. Patients admitted to the hospital with stroke symptoms underwent TCD screening and were grouped into LVO and control groups based on the presence of CTA confirmed occlusion. Velocity curvature index (VCI) was computed from CBFV waveforms recorded at multiple depths from the middle cerebral arteries (MCA) of both cerebral hemispheres. VCI was assessed for 66 patients, 33 of which had occlusions of the MCA or internal carotid artery. Our results show that VCI was more informative when measured from the cerebral hemisphere ipsilateral to the site of occlusion relative to contralateral. Moreover, given any pair of bilateral recordings, VCI separated LVO patients from controls with average area under receiver operating characteristic curve of 92%, which improved to greater than 94% when pairs were selected by maximal velocity. We conclude that VCI is an analytically valid candidate biomarker for LVO diagnosis, possessing comparable accuracy, and several important advantages, relative to current TCD diagnostic methodologies.
尽管经颅多普勒超声（TCD）是一种用于评估中风的便捷便携式技术，但由于获得和解释脑血流速度（CBFV）波形所需的复杂培训要求，它的应用仍然非常有限。客观 TCD 指标对大血管闭塞（LVO）的验证代表了使其能够被接受程度较低的人员使用的重要的第一步。在这项工作中，我们评估了一种新的 TCD 衍生生物标志物在检测 LVO 方面的诊断效用，与当前的标准 CT 血管造影（CTA）相比。因中风症状而住院的患者接受了 TCD 筛查，并根据 CTA 确认的闭塞情况将其分为 LVO 组和对照组。从大脑中动脉（MCA）的多个深度记录 CBFV 波形，计算速度曲率指数（VCI）。对 66 名患者进行了 VCI 评估，其中 33 名患者的 MCA 或颈内动脉有闭塞。我们的结果表明，与对侧相比，同侧大脑半球记录的 VCI 更具信息量。此外，对于任何一对双侧记录，VCI 将 LVO 患者与对照组区分开来，平均接受者操作特征曲线下面积为 92%，当通过最大速度选择对时，该面积提高到大于 94%。我们得出结论，VCI 是一种分析有效的 LVO 诊断候选生物标志物，与当前的 TCD 诊断方法相比，具有相当的准确性和几个重要优势。
