经颅多普勒超声在脑侧支循环评估中的临床应用

脑侧支循环的建立对于缺血性卒中的预后至关重要,便捷有效的脑侧支循环评估方法对 于临床预测卒中患者预后、血管再通治疗效益与风险评价尤为重要。TCD因其可实时检测脑血流动力 学指标、无创伤、可重复、操作便捷、廉价等优点在脑侧支循环评估中发挥着不可替代的作用。本文 检索文献就TCD对脑一、二级侧支循环和脑血管反应性的检测方法、意义及临床应用进展进行综述, 以期为临床诊疗提供帮助。     

The Clinical Relevance of Cerebral Microemboli Detection by Transcranial Doppler Ultrasound

This article reviews the studies on the detection of microemboli by transcranial Doppler ultrasound and the insight these studies have provided into the role of microemboli in the pathogenesis of symptomatic cerebral ischemia.     

Transcranial Doppler Ultrasound Evidence of Active Cerebral Embolization in COVID-19

ObjectiveTo report six consecutive patients with confirmed coronavirus disease-2019 (COVID-19) who underwent Transcranial Doppler (TCD) ultrasonography evaluation for cerebral microemboli in the setting of suspected or confirmed acute ischemic stroke.MethodsPatient data were obtained from medical records from Northwestern Memorial Hospital, Chicago, IL between May and June 2020. All patients with confirmed COVID-19 who underwent clinical TCD ultrasonography for microemboli detection were included.ResultsA total of eight TCD studies were performed in six patients with COVID-19 (4 men and 2 women, median age 65±5), four with confirmed ischemic stroke and two with refractory encephalopathy. Microemboli were detected in three male patients, two patients had suffered a confirmed ischemic stroke and one who developed prolonged encephalopathy. Microemboli of varying intensity were identified in multiple vascular territories in two patients, and microemboli persisted despite therapeutic anticoagulation in a third patient. Of the three patients without evidence of microemboli on TCD ultrasonography, two patients had suffered a confirmed ischemic stroke, while one remained with refractory encephalopathy.ConclusionsTCD ultrasonography for microemboli detection identified three patients with confirmed COVID-19 with evidence of cerebral arterial microemboli, including one who was therapeutically anticoagulated. TCD ultrasonography provides a non-invasive method for evaluating cerebral microemboli in patients with COVID-19 and may be useful in assessing response to treatment in cases with suspected or confirmed disorders of hypercoagulability. Further studies investigating the prevalence of cerebral microemboli and associated risk factors are needed to characterize their pathogenic mechanism and guide therapeutic interventions in hospitalized COVID-19 patients.     

多普勒技术检测药物与支架成形术治疗大脑中动脉狭窄疗效研究

目的 利用经颅多普勒超声（transcranial Doppler,TCD）回顾性对比药物与支架成形术治疗症状性大 脑中动脉（middle cerebral artery,MCA）狭窄的疗效。 方法 收集经数字减影血管造影术（digital s ubtraction a ngiography,DSA）证实一侧MCA存在中-重度 狭窄的患者,包括接受经皮腔内血管支架成形术（percutaneous transluminal angioplasty and stenting, PTAS）联合药物治疗者10例及单纯药物治疗者13例,对两组患者治疗前后TCD显示的血流动力情况 进行研究。 结果 （1）单纯药物治疗组平均随访223.00 d后病变血管血流速度改变较治疗前没有显著差异,而 PTAS联合药物治疗组平均随访496.10 d后支架治疗血管血流速度较治疗后1周显著增快（P =0.013）; （2）最终随访时PTAS联合药物治疗组病变血管血流速度显著低于单纯药物治疗组（P =0.042）;（3） PTAS术后1个月病变血管血流速度下降,但无显著差异,术后3个月、12个月病变血管血流速度与前一 时间段比较显著增快（P =0.002,P =0.020）。 结论 （1）单纯药物治疗可有效阻止血管狭窄的进展;（2）尽管PTAS术后血管发生了一定程度的狭 窄,但最终其血流改善情况明显优于单纯药物治疗组,PTAS的血管重建作用远期有效。     

SonoVue™ in Transcranial Doppler Investigations of the Cerebral Arteries

BACKGROUND AND PURPOSE: The authors investigated the safety and diagnostic potential of a new ultrasound contrast agent (SonoVue) using transcranial color-coded duplex sonography (TCCS). METHODS: Forty patients were enrolled in a multicenter, open-label (on-site), blind (off-site), randomized, dose-ranging crossover study. SonoVue was administered as an intravenous bolus injection of 4 different dosages (0.3, 0.6, 1.2, and 2.4 mL). Efficacy was evaluated as (1) off-site assessment of global quality of the Doppler investigation (based on color or power Doppler images and spectral analysis) at baseline and following each dose of SonoVue according to a 4-point scale (from very poor to excellent imaging of blood flow) and (2) duration of clinically useful signal enhancement and color or power Doppler visualization of blood flow. Additional on-site efficacy assessments performed following each dose of SonoVue included confidence in diagnosis and global consequences of contrast enhancement on diagnosis. Safety evaluations included clinical laboratory tests, neurological examination, injection site tolerability, and incidence of adverse events and their relationship to the study agent. RESULTS: All doses of SonoVue significantly improved the global quality of Doppler examinations (P < .05). The median duration of clinically useful enhancement was dose related (P < .001) and ranged from 2 to 6 minutes at the highest dose. The administration of the contrast agent changed a nondiagnostic study to a diagnostic one in 66% of patients and increased the confidence in diagnosis in 74% of cases. No serious adverse events were recorded following SonoVue administration. The observed adverse reactions were all transient and mild in intensity. CONCLUSIONS: The results obtained from this multicenter study demonstrate that the administration of SonoVue to patients with ischemic cerebrovascular disease who undergo TCCS examination of cerebral vessels improves the visualization of intracranial arteries, providing a dose-dependent contrast enhancement and a clinically useful duration of signal enhancement related to the dose. During this multicenter study, SonoVue proved to be a safe and well-tolerated compound.     

彩色多普勒超声经颅成像与数字减影脑血管造影对颅内动脉瘤检测的比较分析

目的探讨彩色多普勒超声经颅成像（TCI）无创诊断颅内动脉瘤的临床应用价值。方法采用TCI探测已确诊或根据临床症状怀疑颅内动脉瘤的患者120例,与数字减影血管造影（DSA）比较分析。结果与DSA比较,TCI总检出率为71%,直径0.5-1.0cm的动脉瘤,TCI检出率为82%;直径〉1.0cm的动脉瘤,TCI检出率为100%。结论TCI对较大颅内动脉瘤,尤其对直径〉1.0cm动脉瘤的探测有其特征性表现;对较小颅内动脉瘤（直径〈0.5cm）探测,TCI无诊断价值,但可提供颅内血流动力学信息。     

经颅彩色多普勒超声显像在颅内巨大动脉瘤诊断中的应用

目的探讨颅内巨大动脉瘤的彩色多普勒超声血流显像(CDFI)表现,评价其在颅内巨大动脉瘤诊断中的应用价值。方法采用CDFI观察已确诊或根据临床症状怀疑为颅内巨大动脉瘤的21例患者的超声影像学表现,并与数字减影血管造影(DSA)表现进行比较分析。结果以DSA为金标准,CDFI检出率为100%,且能实时动态了解动脉瘤的部位、大小、瘤体内血流特征及载瘤动脉血流速度。结论CDFI对颅内巨大动脉瘤的诊断有其特征性表现,术前行压颈试验了解颅内侧支循环情况对于制定合理的治疗方案有明确的指导意义,CDFI还可作为术后评价疗效和随访的一种影像学检查方法。     

偏头痛相关脑梗死的经颅多普勒超声研究

目的:探讨偏头痛与脑梗死发生的相关性,并运用经颅多普勒(TCD)观察偏头痛性脑梗死患者的脑血流动力学变化方法:运用TCD检测53例偏头痛性脑梗死患者的脑血流,观察记录血流速度、频谱特征并与37例健康查体者比较结果:偏头痛相关脑梗死患者的颅内血流变化以增快为主,尤以后循环显著,与对照组差异有显著统计学意义结论:偏头痛相关脑梗死患者多存在大脑后循环的脑血管痉挛或痉挛性狭窄,TCD对于此类患者的临床诊断、治疗和预后评估具有重要的临床意义。     

Single-Photon Emission Computed Tomography,Transcranial Doppler Ultrasound,and Cerebral Angioplasty for Posttraumatic Vasospasm

Intracranial arterial vasospasm is an important consequence of subarachnoid hemorrhage. In posttraumatic patients, this phenomenon is becoming increasingly recognized with noninvasive techniques that evaluate (1) vascular stenosis, such as transcranial Doppler (TCD) ultrasound, and (2) regional cerebral blood flow, such as single-photon emission computed tomography (SPECT). A posttraumatic patient developed symptomatic vasospasm that was detected by TCD and SPECT and then treated with percutaneous transluminal balloon cerebral angioplasty, which improved the symptoms. The anatomical and functional results of angioplasty were evaluated also by TCD and SPECT, which showed a reduction in the severity of stenosis and improved blood flow, respectively.     

脑动脉硬化诊断与经颅多普勒超声

自Aaslid在1981年发明经颅多普勒超声（transcranial Doppler,TCD）并将其应用于临床已经有近50年的历史,从上世纪八十年代末以超声科华扬教授和神经科黄一宁教授为代表的中国第一批学者将其引入我国也走过二十年的路程,TCD的临床价值在世界范围内已经得到广泛认同,对颅内动脉狭窄的诊断已经被写入美国和欧洲卒中指南,对脑血流中微栓子信号的识别也被写入欧洲早中指南,对脑动脉自动调节功能研完的文章正如雨后春笋般出现在国际医学杂志。但在我国,TCD依然被误读误解,王拥军教授心痛无比地比喻TCD在中国是一个被委屈的孩子。     

经颅多普勒超声评价脑血管反应性和脑血流自动调节

经颅多普勒超声（transcranial Doppler,TCD）能无创、快速地对脑血流动力学进行检查和监 测,被称为脑血管的“听诊器”。目前,TCD不仅用于脑血管痉挛或狭窄等的检查,还被用于脑血管反 应性（cerebral vasoreactivity,CVR）和脑血流自动调节（cerebral autoregulation,CA）的研究,从而预测 卒中发生风险和预后,评估自主神经功能障碍。本文就TCD评价CVR和CA的临床应用价值进行综述, 旨在扩大其应用范围。     

Practice Standards for Transcranial Doppler Ultrasound: Part I—Test Performance

Indications for the clinical use of transcranial Doppler (TCD) continue to expand while scanning protocols and quality of reporting vary between institutions. Based on literature analysis and extensive personal experience, an international expert panel started the development of guidelines for TCD performance, interpretation, and competence. The first part describes complete diagnostic spectral TCD examination for patients with cerebrovascular diseases. Cranial temporal bone windows are used for the detection of the middle cerebral arteries (MCA), anterior cerebral arteries (ACA), posterior cerebral arteries (PCA), C1 segment of the internal carotid arteries (ICA), and collateralization of flow via the anterior (AComA) and posterior (PComA) communicating arteries; orbital windows-for the ophthalmic artery (OA) and ICA siphon; the foraminal window-for the terminal vertebral (VA) and basilar (BA) arteries. Although there is a significant individual variability of the circle of Willis with and without disease, the complete diagnostic TCD examination should include bilateral assessment of the M2 (arbitrarily located at 30-40 mm depth), M1 (40-65 mm) MCA [with M1 MCA mid-point at 50 mm (range 45-55 mm), average length 16 mm (range 5-24 mm), A1 ACA (60-75 mm), C1 ICA (60-70 mm), P1-P2 PCA (average depth 63 mm (range 55-75 mm), AComA (70-80 mm), PComA (58-65 mm), OA (40-50 mm), ICA siphons (55-65 mm), terminal VA (40-75 mm), proximal (75-80), mid (80-90 mm), and distal (90-110 mm) BA]. The distal ICA on the neck (40-60 mm) can be located via submandibular windows to calculate the VMCA/VICA index, or the Lindegaard ratio for vasospasm grading after subarachnoid hemorrhage. Performance goals of diagnostic TCD are to detect and optimize arterial segment-specific spectral waveforms, determine flow direction, measure cerebral blood flow velocities and flow pulsatility in the above-mentioned arteries. These practice standards will assist laboratory accreditation processes by providing a standard scanning protocol with transducer positioning and orientation, depth selection and vessel identification for ultrasound devices equipped with spectral Doppler and power motion Doppler.     

脑供血侧支循环的影像学评估

缺血性脑血管病是危害人类健康的常见病和多发病,随着人们生活水平的提高,发病率 也逐年提高。改善和恢复缺血区的血流灌注是治疗缺血性脑血管病的关键,而良好的侧支循环情况 在此环节发挥着重要作用。对于如何选择最佳的治疗方案以构建良好的侧支循环,系统的影像学评 估是关键。全脑数字减影血管造影术（digital subtraction angiography,DSA）是评估侧支循环的金标准, 能够清晰地显示出侧支血管的分布和所代偿的供血区域,若碍于其有创性,可考虑选择无创技术：经 颅多普勒超声（transcranial Doppler,TCD）测量侧支循环血管的血流流速、确定血流的方向等,计算机 断层扫描血管造影（computed tomography angiography,CTA）从任何角度动态观察颅内的血管和磁共 振成像（magnetic resonance imaging,MRI）显示成像范围内的全部主要的血管及其分支,但各种技术 均存在局限性,掌握各评估技术的优缺点对于做出合理的联合选择非常重要,本文对此展开综述。     

经颅彩色多普勒超声造影在颞骨声窗受限的脑梗死患者颅内侧支循环评价中的应用

目的 探讨经颅彩色多普勒超声造影 （contrast-enhanced transcranial color-coded doppler, CE-TCCD） 技 术在判断颞骨声窗受限的脑梗死及短暂性脑缺血发作 （transient ischemic attack, TIA） 患者颅内侧支 循环方面的应用。 方法 选择由于声窗的限制, 经颅彩色多普勒超声检查未探及颅内血流信号的70例脑梗死及TIA 患者, 应用CE-TCCD检测其颅内血流及Willis环的开放情况, 进一步完善磁共振血管成像 （magnetic resonance angiography, MRA） 后比较两者的诊断结果。 结果 70例患者中男51例, 女19例, 平均年龄 （66.4±11.9） 岁 , CE-TCCD共检出41条交通动脉开放, 其 中38条与MRA诊断一致, 超声造影与MRA诊断一致性好 （Kappa值为0.696, P ＜0.001） 。 超声造影检测 的灵敏度为79.2%, 特异度为91.9%。 结论 在颞骨声窗受限的脑梗死及TIA患者中 , CE-TCCD可用于颅内侧支循环的评价。     

Power Doppler Compared to Color-Coded Duplex Sonography in the Assessment of the Basal Cerebral Circulation

Power–based transcranial duplex sonography (p–TDS) is a new promising ultrasound technique that generates intravascular coloc slgnols from the omplltode of the echo slgnol. The pcesentinvestigation was undertaken to determine the advantages and limitations of power Doppler in the assessment of the basal cerebral circulation compared with transcranial color–coded realtime sonography (TCCS) and contrast–enhanced transcranial color–coded real–time sonography (CE–TCCS). Thirty–eight patients without cerebrovascular diseases were examined with p–TDS and TCCS, and in 11 patients CE–TCCS studies were performed. The M1 segment could be identified in 100% by both ultrasound techniques. p–TDS visualized M2 (67/70 vs 46/70, p < 0.0001), A2 (63/70 vs 46/70, p < 0.001), and P2 (67/70 vs 44/70, p < 0.0001) segments significantly more frequently and accurately compared to TCCS. The posterior communicating artery (25170) and P3 segments (32/70) were only detectable by p–TDS and not by conventional TCCS. In comparison with CE–TCCS, p–TDS had no important advantages in the detection of intracranial vessels. In conclusion, p–TDS and CE–TCCS were superior to TCCS with regard to identification of the basal arterial circulation. Both methods permit noninvasive and reliable identification of the basal cerebral circulation.     

床旁TCD监测对蛛网膜下腔出血后迟发性脑缺血价值研究

目的 探讨床旁经颅多普勒超声（transcranial Doppler,TCD）监测在蛛网膜下腔出血（subarachnoid hemorrhage,SAH）后预测和发现脑血管痉挛,减少迟发性脑缺血（delayed cerebral ischemia,DCI）发生 的价值。 方法 连续纳入2011年10月至2013年10月首都医科大学附属北京天坛医院神内重症监护病房 （intensive care unit,ICU）住院的完成床旁TCD监测的222例SAH患者。记录患者的临床及影像资料、治 疗及并发症。入院24小时内完成TCD基线监测,根据结果分成正常组85例、流速增快组14例、血 管痉挛组123例,比较患者抗血管痉挛强化治疗的使用率、DCI及不良预后［3个月后改良Rankin量表 （modified Rankin Scale,mRS）评分4～6分］的发生率和治疗改善率的差异。 结果 3组患者比较,血管痉挛组和血流增快组的GCS评分低、Hunt-Hess分级Ⅰ～Ⅲ级比例少、世界 神经外科医师联盟（World Federation of Neurosurgical Society,WFNS）分级Ⅰ～Ⅲ级比例少、改良Fisher 分级3～4级所占比例多、颅内血肿发生率多,差异均具有显著性（P <0.05）。血管痉挛组和流速增快 组患者DCI 发生率高于正常组（68.2%、35.7%、3.2%,P＜0.01）。TCD流速增快组和血管痉挛组患者给 予的抗血管痉挛加强治疗（70.6%、100%、4.1%）及脑脊液置换治疗（21.2%、7.1%、5.7%）多,临床缓 解率（56.5%、28.6%、10.6%）高（P＜0.01）。90天随访血管痉挛组和流速增快组预后不良高于正常组 （30.6%、21.4%、15.4%,P =0.031）。 结论 TCD结果异常的患者（血管痉挛组和血流增快组）发病后的病情重,出血量大,尽管给予加强 治疗,DCI的发生率及预后不良率仍高于正常组。床旁TCD监测能够筛查出DCI高危患者并评价治疗效 果,是防治DCI所需的有效检测工具。