This study aimed to develop a sensitive index from transcranial Doppler (TCD) signals for quantitatively evaluating the effects of long-term external counterpulsation (ECP) treatment on stroke rehabilitation. We recruited 27 patients with unilateral ischemic stroke and a good acoustic window within 7 days of stroke onset. 15 of them received 35 daily 1-hour ECP treatment (ECP group) and the others underwent conventional therapy without ECP treatment (No-ECP group). We monitored blood flow in middle cerebral arteries on both sides by TCD, and analyzed them via discrete wavelet analysis method. The overall changes of National Institutes of Health Stroke Scale (NIHSS) and Barthel Index were assessed. A ‘big-wave’ phenomenon was observed in TCD signals of patients in ECP group after 35 days’ treatment, with significant fluctuation in frequency interval from 0.010 to 0.034 Hz as main feature. A new index, which was denoted as ${I}$ , was derived from this phenomenon. The ${I}$ was significantly higher for patients in ECP group than that for patients in No-ECP group after 35-days’ treatment ( ${P} < $ 0.01). And the ${I}$ was positively correlated with NIHSS change in ECP group ( ${P} < 0.05$ ). The new index could be used as an effective indicator for evaluating enhancement of endothelial metabolism and neurogenic activity after long-term ECP treatment.

中文翻译：

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使用外部反搏评估中风康复的经颅多普勒信号指数

本研究旨在从经颅多普勒 (TCD) 信号中开发一个敏感指标，用于定量评估长期体外反搏 (ECP) 治疗对中风康复的影响。我们招募了 27 名患有单侧缺血性中风且在中风发病 7 天内具有良好声窗的患者。其中15人接受35次每日1小时ECP治疗（ECP组），其余接受常规治疗，未接受ECP治疗（No-ECP组）。我们通过TCD监测两侧大脑中动脉血流，并通过离散小波分析方法进行分析。评估美国国立卫生研究院卒中量表（NIHSS）和Barthel指数的整体变化。ECP组患者治疗35天后TCD信号出现“大波”现象，频率区间从 0.010 到 0.034 Hz 的显着波动为主要特征。一个新的索引，表示为 ${I}$ , 源于这种现象。这 ${I}$ 治疗 35 天后，ECP 组患者显着高于 No-ECP 组患者（ ${P} < $ 0.01）。而 ${I}$ 与 ECP 组 NIHSS 变化呈正相关（ ${P} < 0.05$ ）。新指标可作为评价长期ECP治疗后内皮代谢和神经源活性增强的有效指标。