经颅彩色多普勒超声对大脑中动脉狭窄的诊断价值

经颅彩色多普勒超声（TCCD）能通过颅骨特定部位的声窗对颅内血管进行结构和功能评价,为成人颅内血管监测及脑血管疾病的诊断提供了一种有价值的检查手段。本研究通过TCCD对临床疑有颅内动脉狭窄的患者进行检查,并与数字减影血管造影（DSA）结果对照,旨在探讨TCCD诊断大脑中动脉（MCA）狭窄的准确性。     

TCD与经颅彩色多普勒对大脑中动脉狭窄的检测

目的 :比较 TCD与经颅彩色多普勒 (TCCD)和能量多普勒 (PDI)对 2 8例大脑中动脉 (MCA)狭窄的诊断。方法 :应用 TCD仪检出高流速改变的 MCA,再经 TCCD及 PDI准确测量 MCA的血流速度和血管内径 (或彩色血流直径 )。结果 :TCD对 MCA狭窄的检出率与 TCCD和 PDI的检出率明显相关。结论 :TCCD和 PDI极大提高了颅内血管病变检出的准确性 ,TCD对脑血管造影的患者起了良好的筛选作用     

经颅超声造影在大脑中动脉狭窄定位及定量诊断中的初步应用

目的探讨经颅超声造影(CE-TCCS)在大脑中动脉(MCA)狭窄闭塞病变诊断中的应用价值。方法对86例临床疑似大脑中动脉狭窄闭塞的患者分别行经颅彩色多普勒超声(TCCS)及经颅超声造影检查,比较造影前后大脑中动脉狭窄显示率、定位狭窄部位、评价狭窄程度,并与核磁共振血管成像和(或)数字减影血管造影检查结果进行对照。结果经核磁共振血管成像和(或)数字减影血管造影显示,86例中98支大脑中动脉狭窄,经颅彩色多普勒超声诊断狭窄79支(79/98,80.6%),经颅超声造影诊断狭窄98支(98/98,100%),其中M1段狭窄68支,M2段狭窄30支;经颅超声造影对大脑中动脉狭窄定位诊断准确率为94.9%(93/98),不同程度的大脑中动脉狭窄表现不同。结论经颅超声造影能够准确诊断大脑中动脉狭窄,狭窄部位定位准确,对狭窄程度的评价有一定作用,有望成为大脑中动脉狭窄闭塞病变首选的筛查方法。     

彩色多普勒超声成像与经颅多普勒超声成像联合检查对颈部血管狭窄的诊断价值

目的探讨彩色多普勒超声成像与经颅多普勒超声成像联合检查在颈部血管狭窄临床诊断中的价值。方法选取疑似颈内动脉狭窄的缺血性脑血管疾病患者99例,所有患者均做颈脑血管造影、彩色多普勒超声及经颅多普勒超声成像检查,以血管造影的检查结果为金标准,观察患者颈内血管病变情况;比较彩色多普勒超声、经颅多普勒超声成像的检查结果及二者联合检查结果与血管造影检查结果相比较的准确率和敏感性、特异性、阴性及阳性预测值。结果 99例患者经血管造影检查共检测198支血管,正常68支(34.3%);病变血管130支[包括闭塞32支(16.2%)、重度狭窄98支(49.5%)];双侧狭窄34例(34.3%),单侧闭塞32例(32. 3%),单侧狭窄33例(33. 3%)。对比血管造影检查结果 ,彩色多普勒超声的准确率为88. 9%,经颅多普勒超声成像检查结果的准确率为84. 8%,彩色多普勒超声+经颅多普勒超声成像联合检测的准确率为98. 99%。经颅多普勒超声成像与彩色多普勒超声+经颅多普勒超声成像对比血管造影的准确率差异有显著性(x^2=27. 3,P<0. 05);彩色多普勒超声与彩色多普勒超声+经颅多普勒超声成像对比血管造影的准确率差异有显著性(x^2=26.7,P<0.05)。彩色多普勒超声+经颅多普勒超声成像联合检测的敏感性为98.2%,特异性为100.0%,阴性预测值为96. 9%,阳性预测值为100.0%,显著高于彩色多普勒超声及经颅多普勒超声成像单独检测结果的敏感性、特异性及阴性、阳性预测值(P<0. 05)。结论彩色多普勒超声及经颅多普勒超声成像联合检查,可显著提高临床中对颈动脉闭塞或狭窄的诊断准确率。     

经颅彩色及频谱多普勒超声评价大脑中动脉狭窄支架术血流动力学变化

目的 应用经颅彩色及频谱多普勒超声观察大脑中动脉(MCA)支架成形术前后的血流动力学变化.方法 对30例大脑中动脉狭窄的患者行经颅超声检查,采用二维及频谱多普勒对比观察MCA支架成形术前、术中即刻及术后的血流动力学变化.所有患者均经数字减影血管造影检查确诊.结果 30例MCA狭窄患者彩色多普勒超声检查均成功显像.28例...     

经颅超声技术的应用与发展

经颅超声技术可分为两大类，一种为经颅多普勒超声（transcranial Doppler，TCD），采用经彩色编码的脉冲波多普勒超声检测脑血管，主要检测与脑动脉血流速度有关的参数。另一种为经颅彩色双功能超声（transcranial color-coded duplex sonography．TCCS）或经颅彩色多普勒超声（transcranial colordoppler ultrasound，TCCD），     

经颅彩色多普勒超声在诊断颅内动脉狭窄中的应用

目的探讨经颅彩色多普勒超声（TCCD）在颅内动脉狭窄诊断中的价值。方法对30例疑有颅内动脉狭窄的患者应用TCCD观察颅内各动脉的形态、走行，应用频谱多普勒测量各条血管的血流参数，包括收缩期峰值流速、舒张末流速、平均流速、阻力指数，并与数字减影血管造影（DSA）结果进行对比分析。结果16例TCCD诊断为颅内动脉狭窄，14例经DSA证实。TCCD诊断颅内动脉狭窄的特征是狭窄处彩色血流束变细，典型者呈“束腰征”；频谱多普勒显示狭窄处血流速度异常增高，频谱形态呈湍流，同时音频信号响亮。狭窄严重者彩色血流束连续性欠佳或者中断，血流速度不增快或者明显减低。血管闭塞者血流不显示。结论TCCD对于颅内动脉狭窄具有一定的诊断价值，可作为早期筛检性诊断方法。     

经颅超声造影在颅内动脉狭窄闭塞性疾病的应用

目的探讨经颅超声造影在颅内动脉狭窄闭塞性疾病的应用价值。方法 59例患者超声造影前、后分别经颅超声探查颅内动脉及颈内动脉颅内段,比较造影前、后颅内动脉的显示率,总结经颅超声造影在颅内动脉狭窄闭塞性疾病的血流特点,并与MRA或DSA结果对比。结果造影增强经颅彩色多普勒(CE-TCCS)对于大脑前动脉(ACA)、大脑中动脉(MCA)、大脑后动脉(PCA)显示率较常规经颅彩色多普勒(TCCS)明显提高,其中对于MCA(M2段)、ACA(A1、A2段)、PCA(P1、P2段)的显示率与TCCS比较,差异有统计学意义(P0.01)。21例椎-基底动脉造影前显示率为71.3%(15/21),造影后显示率为100%;CE-TCCS检出3例MCA闭塞,15例MCA狭窄,3例ACA狭窄,2例PCA狭窄;4例颈内动脉颅内段闭塞,7例颈内动脉颅内段狭窄。颈内动脉颅外段闭塞3例和狭窄8例,患者同侧颅内动脉血流灌注减少,血流速度减低。2例MCA狭窄支架置入术后,CE-TCCS显示血流通畅,速度在正常范围,所有结果均经MRA、DSA证实。结论经颅超声造影可以提高颅内动脉的显示率;有助于判断颅内动脉狭窄,也可用于颅内动脉狭窄支架置入术后疗效评价。     

经颅多普勒与彩色多普勒超声联合应用对锁骨下动脉盗血综合征的血流动力学观察

目的 探讨经颅多普勒超声（TCD）与彩色多普勒血流显像联合检查锁骨下动脉盗血综合征的诊断价值。方法 锁骨下动脉盗血综合征患者24例，均经临床检查及相关影像学检查确诊，其中14例经血管造影（DSA）检查，10例经磁共振血管造影检查（MRA），采用TCD方法观察椎动脉颅内段血流方向及频谱的变化，二维超声显示椎动脉颅外段、颈动脉、锁骨下动脉及无名动脉的内膜和内径，彩色及频谱多普勒检测血流方向及速度。结果 TCD检查时，24例患者中18例均表现为椎动脉血流反向，肢体束臂试验反向血流增加，6例血流方向正常，束臂试验患侧椎动脉反向峰值血流速度增快，或由正向变为反向。二维超声示引起锁骨下动脉盗血综合征的病因动脉硬化占90％，大动脉炎占10％。结论 TCD诊断锁骨下动脉盗血综合征具有直观、快捷、准确的优点，结合二维及彩色多普勒超声可以明确锁骨下动脉盗血综合征的病因、病变部位及程度。     

经颅二维彩色多普勒超声对脑梗死患者大脑中动脉血流速度的研究

目的探讨经颅二维彩色多普勒超声(TCCS)对脑梗死患者大脑中动脉血流速度。方法应用经颅彩色多普勒超声对临床经血管造影确诊为脑梗死的患者48例(其中18例大脑中动脉主干梗死,14例大脑中动脉分支梗死,16例颅外单侧颈内动脉梗死)和50例健康成人分别采用经颅彩色多普勒血流显像(CDF I)进行探测,测量双侧大脑中动脉舒张末期血流速度(EDV),并计算舒张末期双侧大脑中动脉血流速度比率(健侧与患侧的比值)。结果在健康成人组中,舒张末期血流速度和舒张末期比率为:(42.79±13.72)cm/s、1.25±0.31;在大脑中动脉水平段主干梗死组及大脑中动脉分支梗死组舒张末期血流速度和舒张末期比率分别为:(17.20±5.65)cm/s、3.56±1.20,(20.14±4.35)cm/s、1.82±0.46;颅外单侧颈内动脉梗死组中,梗死侧的舒张末期血流速度和舒张末期比率为:28.70±11.21(cm/s)、1.68±0.57,所有梗死组舒张末期血流速度明显低于对照组,而舒张末期比率明显高于对照组。结论经颅二维彩色多普勒对大脑中动脉(MCA)水平段血流速度和舒张末期比率的检测,有助于大脑中动脉梗死的鉴别诊断。     

经颅多普勒超声对椎-基底动脉供血不足的诊断及评定价值

为探讨经颅多普勒超声对椎－基底动脉供血不足患者的诊断及评定价值,按临床诊断标准收集椎－基底动脉供血不足患者８０例,对照组为年龄相近的健康人５１例,采用ＭＴ－１０００型彩色经颅多普勒超声仪对基底动脉、椎动脉、大脑后动脉、大脑前动脉和大脑中动脉的血流速度、搏动指数及血流频谱图像进行检测分析。结果：疾病组椎－基底动脉流速明显低于对照组（Ｐ〈０．００１）,且搏动指数值增高（Ｐ〈０．０５）。疾病组经颅多普勒     

Transcranial Doppler Sonography in Pediatric Neurocritical Care

Transcranial Doppler sonography is a noninvasive, real‐time physiologic monitor that can detect altered cerebral hemodynamics during catastrophic brain injury. Recent data suggest that transcranial Doppler sonography may provide important information about cerebrovascular hemodynamics in children with traumatic brain injury, intracranial hypertension, vasospasm, stroke, cerebrovascular disorders, central nervous system infections, and brain death. Information derived from transcranial Doppler sonography in these disorders may elucidate underlying pathophysiologic characteristics, predict outcomes, monitor responses to treatment, and prompt a change in management. We review emerging applications for transcranial Doppler sonography in the pediatric intensive care unit with case illustrations from our own experience.     

经颅多普勒超声对脑死亡的诊断意义

目的:探讨经颅多普勒超声(TCD)对脑死亡的诊断意义。方法:选择临床拟诊断脑死亡患者32例,行TCD检查双侧大脑中动脉、基底动脉,每12 h观察1次,至少重复2次,终点事件为患者心跳不可逆停止,记录每种血流频谱出现的时间及持续时间。结果:所有患者均在发现振荡波后1-7 d内出现心跳不可逆停止,出现钉子波频谱后患者于0-48 h内出现心跳不可逆停止,出现血流信号消失的患者于0-12 h内出现心跳不可逆停止,每种频谱持续的时间长短不同。结论:在脑电图及诱发电位基础上行TCD检查可提高脑死亡诊断准确性达100%;脑死亡各种TCD频谱呈规律性改变,依次出现振荡波、钉子波及血流信号消失。     

超声评价脑血流自身调节功能时不同脑血管阻力变化差异性的研究

目的观察冷加压试验（CPT）下多普勒超声所测不同脑血管阻力变化的差异性，为通过多普勒超声评定脑电流的自身调节功能选择合适的脑血管。 方法记录CPT中27例健康青年人右侧大脑中动脉，右侧颈内动脉和右侧椎动脉的时间平均最大流速（Vm），并同步记录血压，计算相对血管阻力（VR），进行统计学分析。 结果CPT中，右侧大脑中动脉（RMCA）、右侧颈内动脉（RICA）和右侧椎动脉（RVA）的VR均随着平均动脉压（MAP）的上升而明显增加，其中RICA的VR增加率与MAP上升率基本一致，而RMCA和RVA的VR增加率略小于MAP的上升率（P＜0．05）。 结论在CPT中，交感神经兴奋对颈内动脉内径的影响比对大脑中动脉和椎动脉内径的影响要小，因此，颈内动脉Vm的变化能较准确地反映其实际血流量的变化。颈内动脉是多普勒超声评定腩血流自身调节功能最为适宜的脑血管。     

经颅彩色多谱勒与DSA对比研究颅内动脉瘤的诊断价值

目的：评价经颅彩色多谱勒（TCCS）诊断颅内动脉瘤的临床价值。方法：采用TCCS对43例临床怀疑脑血管病患者进行检测,观察颅内主要动脉走行、形态,检测各项血流参数,盲法与DSA结果进行对比分析。结果：TCCS诊断颅内动脉瘤灵敏度71％,特异度83％,准确度79％,假阳性率17％,假阴性率29％,阳性预告值67％,阴性预告值86％,阳性似然比4．2,阴性似然比0．35,约登指数0．54。结论;TCCS对颅内动脉瘤的诊断具有较高的实用价值,可作为早期筛检性诊断。     

Contribution of transcranial color-coded real-time sonography to the etiopathogenetic classification of middle cerebral artery stenosis

Transcranial color-coded real-time sonography (TCCS) and cranial computed tomography were applied to patients with middle cerebral artery (MCA) stenosis to evaluate whether these techniques may disclose additional aspects of the pathophysiology of the stenotic lesion. In 15 patients with MCA stenosis identified by transcranial Doppler sonography, the echogenicity of the stenotic segment was estimated subjectively by TCCS. The density of the stenotic segment, prior to being detected by TCCS, was quantified by computed tomography. In 5 of the 15 patients, transcranial image-directed Doppler sonography identified a hyperechogenic lesion in association with the stenotic vascular segment; computed tomography demonstrated a “dense” artery (Hounsfield units [HU] > 120) in the corresponding vascular segment. In 10 patients the echogenicity of the stenotic segment was found to be normal, with a computed tomography density of >100 HU in the corresponding segment. Hyperechogenic and hyperdense stenotic vascular segments in TCCS and computed tomography, respectively, may indicate an arteriosclerotic vascular lesion with calcium deposits. Normal echogenicity and normal to slightly elevated computed tomography-density of a stenotic vascular segment may suggest the presence of a thrombotic/embolic lesion. © 1994 John Wiley & Sons, Inc.     

Cerebrovascular reserve capacity in patients with hyperlipidemia

PURPOSE: Because recent data are conflicting, it is not certain whether hyperlipidemia is an independent risk factor for cerebrovascular diseases. Decreased cerebrovascular reserve capacity refers to the decreased ability of the cerebral arterioles to adapt in critical conditions and probably predicts a higher risk of stroke. The aim of this study was to compare cerebrovascular reserve capacity in hyperlipidemic patients and healthy controls using transcranial Doppler sonography. METHODS: Thirty-four hyperlipidemic patients and 21 healthy controls were examined. With transcranial Doppler sonography, the mean blood flow velocity in the middle cerebral artery was registered at rest and at 5, 10, 15, and 20 minutes after intravenous administration of 1,000 mg acetazolamide. Cerebrovascular reactivity and reserve capacity were calculated from mean blood flow velocities. Various laboratory measurements were also made and assessed for correlation with resting cerebral blood flow velocity and cerebrovascular reserve capacity. RESULTS: No significant differences could be observed between controls and hyperlipidemic patients in cerebrovascular reactivity or cerebrovascular reserve capacity. No correlation was found between various laboratory measurements and resting cerebral blood flow velocity or cerebrovascular reserve capacity. CONCLUSIONS: We could not demonstrate any differences in cerebrovascular reserve capacity between hyperlipidemic patients and healthy controls. Thus, the vasodilatory ability of the cerebral arterioles seems to remain unchanged in this patient group and is not correlated with the severity of hyperlipidemia.     

Cerebral blood flow and CO2 reactivity in interictal migraineurs: a transcranial Doppler study

There is still some controversy about alterations in velocity of blood flow and in cerebral vasomotor reactivity of intracranial arteries in migraineurs during the interictal phase. By means of simultaneous bilateral transcranial Doppler ultrasonography we, therefore, assessed intracranial blood flow velocities and cerebrovascular reactivity to carbon dioxide of all three basal brain arteries in 20 migraineurs during the interictal phase and 30 nonheadache-prone control subjects. Mean blood flow velocities were higher in migraineurs than in controls in all three arteries on both sides, with a significant difference (P < 0.05) for the right anterior cerebral artery and middle cerebral artery under basal conditions and for the right posterior cerebral artery during hypercapnia. Similarly, the cerebrovascular reactivity to carbon dioxide was always higher in patients than in controls, with a significant difference for the left anterior and the right middle cerebral arteries (P < 0.05) and the right posterior cerebral artery (P < 0.01). The broad overlap of cerebrovascular blood flow velocities and CO2 reactivities in patients and controls precluded identification of values diagnostic of migraine. Nevertheless, transcranial Doppler ultrasonography offers the opportunity to noninvasively monitor cerebral blood flow parameters and, therefore, represents a valuable tool for vascular research in migraine.     

肝脏肿瘤谐波造影三维超声与造影二维超声的比较

目的通过与谐波造影二维超声的比较．探讨谐波造影三维超声在评价肝脏肿瘤血供中的作用。方法采用编码谐波造影功能对21例肝脏肿瘤患者行造影二维超声检查，并在此基础上进行三维重建，比较两者在显示肿瘤血管像、灌注像、血管及灌注综合像方面的不同。结果谐波造影三维超声较造影二维超声能更清楚地显示肿瘤的血管像，显示血管及灌注综合像的能力亦优于造影二维超声，但在显示肿瘤灌注像方面，二者作用相似。结论谐波造影三维超声能更好地反映肝脏肿瘤的血供特点，可为肝脏肿瘤的影像研究提供一种新方法。