经颅彩色多普勒在大脑中动脉狭窄经皮血管成型并支架植入术前后的应用价值

目的 评价经颅彩色多普勒（TCD）在大脑中动脉狭窄经皮血管成型并支架植入术前后的应用价值。方法 47例临床表现为反复发作一过性脑缺血（TIA）或脑梗死患者，TCD及数字减影血管造影（DSA）诊断为大脑中动脉狭窄，行血管成型并支架植入术（PTAS），对狭窄血管经PTAS治疗前后形态学及大脑中动脉血流动力学各项指标（平均流速Vm、收缩峰流速Vs、舒张峰流速Vd、脉动指数Pi、阻力指数Ri）进行分析和比较，并与DSA进行比较。结果 41例与术前比Vs、Vm、Vd下降，Pi值增高，Ri值变化不大，TCD及DSA随访所有例患者无再发狭窄；5例患者出现Vs、Vm、Vd增快，Pi值增高，但均未见反流信号；I例出现Vs增快，Vm增快，Vd降低。中、重度狭窄TCD与DSA相符率分别为75％、83％。结论 TCD能为血管内支架术治疗大脑中动脉狭窄前后疗效提供客观依据，其无创、便捷、廉价的优点，更有优势作为PTAS治疗中、重度MCA狭窄的初选、疗效评价和术后随访的评定方法。     

B超对老年高血压病人脑血管狭窄的诊断价值

目的：B超对老年高血压病人脑血管狭窄的诊断价值。方法：采用以色列Rjmed公司Translink9000 型TCD仪行颅底血管检测，采用美国ATL-Ultramark9型线阵探头彩色多普勒血流显像仪，探头频率5MHz，声束与血流的夹角为60度行颅外颈动脉血管检查。结果：脑动脉血流动力学(颅内以MCA为例)测定结果显示，高血压组和对照组比较，Vs、Vd、Vm、PI、RI有显著性差异。结论：TCD和颈动脉B超的双重检测对脑血管狭窄的诊断有较好的可靠性和准确性。     

福辛普利对糖尿病患者视网膜中央动脉血流动力学的影响

目的 观察糖尿病患者用福辛普利治疗前后视网膜中央动脉（CRA）血流动力学变化。方法 19例（38眼）糖尿病患者给予福辛普利10mg/d,于治疗前和治疗后1周用彩色多普勒超声检测CRA收缩期峰值血流速度（Vs）、舒张末期血流速度（Vd）、平均血流速度（Vm）、搏动指数（PI）和阻力指数（RI）,并与正常组对照。结果 糖尿病患者CRA的Vs、Vd、Vm低,而PI、RI高于对照组,治疗后患者的Vs、Vd和Vm增加,PI、RI降低（P＜0.05或0.01）。结论 福辛普利能改善糖尿病患者CRA血流动力学,彩色多普勒超声可用于评价糖尿病患者CRA血流动力学变化。     

经颅多普勒对颅内动脉狭窄诊断的临床应用

目的：探讨颅内动脉狭窄经颅多普勒（TCD）检测特点,筛选对于诊断有价值的检测指标。方法：TCD检测86例缺血性脑血管病（ICVD）患者收缩期峰流速（Vp）、舒张末期流速（Vd）、平均血流速度（Vm）、阻力指数（RI）及脉动指数（PI）,着重对血管反应性进行观察。结果：86例患者颅内动脉狭窄为中轻度31例,中度17例,重度12例,大脑中动脉闭塞5例,共计65例为颅内动脉狭窄组（狭窄组）,无动脉狭窄21例为无狭窄组。狭窄组患者大脑中及前动脉血管反应性明显低于非狭窄组（P〈0.05）;轻、中度患者Vp、Vd、Vm、RI及PI与非狭窄组比较无明显改变,重度患者则可见Vp低于非狭窄组（P〈0.01）。结论：TCD是诊断颅内动脉狭窄的有效手段;与MRI及血管造影取长补短,可提高颅内动脉狭窄的诊断率,并可作为ICVD高发人群筛选工具。血管反应性是诊断颅内动脉狭窄的敏感指标,血流速度只能起参考作用,不能作为颅内动脉狭窄的诊断依据及分级标准。     

被动吸烟大鼠脑血流动力学变化的实验研究

目的 研究被动吸烟大鼠颈动脉内皮细胞形态学与脑血流动力学的改变情况,探讨吸烟与脑血管病发生的关系.方法 制备被动吸烟大鼠模型;应用透射电镜观察颈动脉内皮细胞的形态学变化,利用经颅彩色多普勒(TCD)测定脑血管血流动力学参数.结果 1.吸烟组颈动脉内皮细胞正常超微结构被破坏.2.吸烟组脑血管Vs、Vd、Vm较对照组显著减慢(P＜0.05),PI、RI显著增高(P＜0.05).结论 吸烟通过引起血管内皮细胞的损伤与脑血流速度减慢、血管阻力增大,导致脑血管疾病的发生.     

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...     

飞行人员模拟急进高原缺氧后脑血管反应性的超声评估

目的应用经颅彩色多普勒(TCCD)对模拟急进高原缺氧暴露初期脑血管血流参数进行监测, 评估脑血流动力学及脑血管反应性变化趋势。方法选取2021年参加飞行训练的64名健康志愿者, 应用TCCD技术观察受检者快速进入模拟海拔4 500 m的低氧环境30 min后大脑中动脉收缩期峰值流速(Vs)、舒张末期流速(Vd)、平均血流速度(Vm)、阻力指数(RI)及搏动指数(PI)等血流参数变化情况;并结合屏气试验, 利用屏气指数(BHI)对受检者脑血管反应性(CVR)进行评估, 将受检者分为≤30岁和>30岁两个年龄段, 比较其缺氧后CVR的变化情况。结果进入缺氧环境初期, 与之前相比, 受检者脉搏血氧饱和度(SpO2)降低, 心率增快, 大脑中动脉血流速度(Vs、Vd、Vm)明显升高, BHI降低(均P<0.01);缺氧后, 与≤30岁受检者相比, >30岁者BHI变化率减低(P<0.05);屏气后, 脑血流速度均明显上升, PI和RI明显降低(均P<0.05)。结论脑血流对缺氧十分敏感, 应用TCCD技术可以实时、精准评估快速缺氧环境下脑血流动力学变化趋势和脑血管...     

缺血性脑卒中和颈内动脉迂曲的相关性研究

目的通过研究缺血性脑卒中并颈内动脉迂曲患者的脑血流动力学变化,探讨缺血性脑卒中和颈内动脉迂曲的相关性。方法选取我院收治的缺血性脑卒中伴双侧颈内动脉迂曲患者50例为双侧组,单侧颈内动脉迂曲患者50例为单侧组,并选取同期双侧颈内动脉正常患者50例设为正常组。三组患者均行磁共振血管成像(MRA)及经颅多普勒超声(TCD)后联合确诊为颈内动脉迂曲,并以TCD行血流动力学评估,比较三组患者颅内血流动力学变化。结果单侧组迂曲侧和非迂曲侧大脑中动脉平均血流速度(Vm)、收缩期峰速(Vs)、舒张末期流速(Vd)、搏动指数(PI)比较差异无统计学意义(P>0.05);双侧组Vm、Vs、Vd、PI明显低于正常组(P<0.05)。结论颈内动脉迂曲可引起颅内血流动力学变化,在一定状态下,严重的动脉迂曲可能是缺血性脑卒中相关因素之一。     

双功能经颅彩色多普勒超声对疑似椎-基底动脉供血不足的诊断价值

目的探讨双功能经颅彩色多普勒超声对疑似椎-基底动脉供血不足的诊断价值。方法对298例疑似椎-基底动脉供血不足患者采用双功能经颅彩色多普勒超声检查,并对椎动脉（VA）、基底动脉（BA）血管的收缩峰流速（Vs）、舒张期末流速（Vd）、平均血流速度（Vm）、搏动指数（PI）进行测定。结果 298例患者中,椎-基底动脉供血不足280例,正常18例。血流速度增高93例（33.2%）,VA：Vs（54.50±10.10）cm.s-1,Vd（29.80±9.70）cm.s-1,Vm（49.70±9.30）cm.s-1,P...     

老年糖尿病患者脑血管病变的经颅多普勒超声分析

目的探讨经颅多普勒超声(TCD)在诊断和预测老年糖尿病患者脑血管病变中的临床应用价值.方法对32例糖尿病无脑梗死患者,31例糖尿病并脑梗死患者及31例健康者的995条脑血管,进行TCD检测,就收缩期峰血流速度(Vs)、舒张末期血流速度(Vd)、平均血流速度(Vm)、脉动指数(PI)、阻力指数(RI)值等检测;各参数的结果作比较分析.结果 3组颅内血流参数比较,两疾病组血流速度异常以Vs增快为多见,尤以颈内动脉终末端(ICA)、基底动脉(BA)异常为突出特点;两疾病组血管涡流检出率和血管条数均高于对照组;糖尿病组TCD异常率52.3%,而糖尿病合并脑梗死组57.8%,均明显高于对照组.结论 TCD检测对预测和预防糖尿病患者脑血管病发生,判断预后,指导早期治疗,预防脑梗死发生具有重要价值.     

颈内动脉严重狭窄或闭塞的近、远段动脉血流动力学改变

[目的]探讨颈内动脉严重狭窄或闭塞的近、远段动脉的血流动力学改变.[方法]对121例经数字减影血管造影(DSA)或磁共振血管成像(MRI)证实的颈内动脉严重狭窄或闭塞患者(患者组)和80例无颈内动脉病变患者(对照组)行经颅多普勒超声(TCD)检测.[结果]近段的颈总动脉血流波形异常,表现为收缩峰尖窄、舒张期血流速明显减低或消失或舒张早期血流逆转;与对照组比较血流速度减低,搏动指数明显增高(P＜0.01).远段的大脑中动脉血流波形异常,表现为收缩峰圆钝、舒张期血流速增高;血流速度和搏动指数明显低于对照组(P＜0.01).[结论]TCD有助于了解颈内动脉严重狭窄或闭塞的近、远段动脉的血流动力学改变,为临床确定诊断和更深入研究缺血性脑血管病的发病机制提供重要的客观依据.     

Receiver operating characteristic curves of transvaginal Doppler blood flow measurements in benign and malignant adnexal tumors.

The role of receiver operating characteristic curves of transvaginal Doppler velocimetry in predicting malignancy was evaluated in 80 patients with benign and 40 patients with malignant adnexal tumors. The mean values of peak systolic velocity did not differ significantly. Malignant tumors had a significantly higher end diastolic velocity and mean flow velocity than benign tumors. Benign tumors had a significantly higher ratio of peak systolic to end diastolic velocity, pulsatility index, and resistive index than malignant tumors. The diagnostic accuracies in predicting malignancy were as follows: peak systolic velocity, 62%; end diastolic velocity, 79%; ratio of peak systolic to end diastolic velocity, 63%; mean flow velocity, 73%; pulsatility index, 91%; resistive index, RI 92%. Doppler velocimetry analysis allows us to predict the presence of malignancy with limited reliability.     

TCD检测系统性红斑狼疮患者脑血流动力学变化

目的：了解系统性红斑疮患者脑血流动力学状况,方法;利用经颅我镨勒（ＴＣＤ）测定纤斑疮患者和健康对照组脑血管收缩峰速度（Ｖｓ）、舒张期血流速度（Ｖｄ）、平均血流速度（Ｖｍ）、收缩／舒张比值（Ｓ／Ｄ）、血管搏动指数（ＰＩ）、阻力指数ＲＩ）。结果：红斑狼疮患者无Ｖｓ、Ｖｍ是否升高,各脑血管Ｖｄ均较对照组显著增快（Ｐ〈０．０１）,ＰＩ、ＲＩ显著降低（Ｐ〈０．０１）,突出表现为低的ＴＣＤ频谱改变。结论：红斑     

Comparison of visually evoked peak systolic and end diastolic blood flow velocity using a control system approach.

Transcranial Doppler sonography measures blood flow velocity in basal cerebral vessels with high accuracy. For quantification, time averaged mean blood flow velocities are used most because the peak systolic and end diastolic blood flow velocities mark the velocity extremes of one heart cycle. It is known, from hemodynamic measurements of the neurovascular coupling mechanism, that the end diastolic velocity is more sensitive for change in hemodynamics than the peak systolic velocity. Thus, we used a recently introduced control system approach to compare both indices for their use in functional transcranial Doppler tests focusing on hemodynamics of blood flow velocity change. We enrolled 65 healthy young volunteers without a medical history of cardiovascular risk factors, and performed a visual stimulation test. Peak systolic and end diastolic maximal blood flow velocities were used after transformation to relative data for control-system analysis. Due to Doppler artefacts, 95% of peak systolic and 86% of end diastolic data sets were analyzed. Results showed statistically significant differences for resting blood flow velocity and the control system parameter gain, attenuation and rate time, whereas the parameters' natural frequency and time delay were equal. Increase in relative blood flow velocity in the posterior cerebral artery due to visual-cortical stimulation was higher in end diastolic values than peak systolic data. Using a complex visual stimulation paradigm, the higher sensitivity of the end diastolic index is of no practical use. Being less influenced by Doppler artefacts, the peak systolic velocity index is more feasible for control-system analysis of dynamic blood flow regulation.     

经颅多普勒在颅内动脉狭窄支架成形术前后及再狭窄监测中的应用

目的评价经颅多普勒（TCD）在颅内动脉狭窄支架成形术前后及再狭窄监测中的应用。方法85例脑梗死或短暂性脑缺血发作（TIA）患者,经数字减影血管造影（DSA）检查证实为颅内动脉重度狭窄。在支架置入术前、术后3d及术后半年进行TCD检查,检测大脑中动脉（MCA）、颈内动脉终末段（ICA1）、椎动脉（VA）、基底动脉（BA）的血流动力学指标收缩峰流速（Vs）、声频等。结果85例患者术前术后DSA及TCD检查符合率为100％。3例术后半年TCD复查诊断为再狭窄,DSA检查3例患者支架内狭窄〉50％。与术前比较,85例患者术后3d MCA、ICA1、VA及BA的Vs明显下降,P〈0．01,差异有统计学意义;涡流、杂音消失。术后半年TCD复查,与术后3d比较,P值分别为：0．461、0．968、0．974及1．000,差异无统计学意义。结论TCD是理想判定颅内血管内支架成形术后疗效及随访的首选检测方法。     

Prediction of brain blood flow using pulsed Doppler ultrasonography in newborn lambs

The purpose of this study was to evaluate the ability of pulsed Doppler ultrasonography to predict brain blood flow by comparing measurements made in basal cerebral arteries using a pulsed Doppler system with measurements of brain blood flow using radioactive microspheres in lambs. We measured the instantaneous maximum velocity during peak systole and end diastole and the mean velocity over the pulse cycle in basal cerebral arteries, calculated Pourcelot's index of resistance and Gosling's pulsatility index, and used regression analysis to compare the pulsed Doppler measurements with brain blood flow measured with radioactive microspheres. Pulsed Doppler measurements of the peak systolic, end diastolic, and mean flow velocity in basal cerebral arteries were directly related to brain blood flow. In contrast, no linear relationship was detected between the resistance or pulsatility indices and brain blood flow measured by microspheres (p greater than 0.14). Prediction of brain blood flow for individual subjects lacks the quantitative precision necessary for use as a clinical tool. However, the direct relationship between brain blood flow and the peak systolic, end diastolic, and mean flow velocities in basal cerebral arteries supports the use of these measurements in clinical research for the qualitative assessment of change in brain blood flow.     

Use of intravascular Doppler velocimetry during angioplasty of failing hemodialysis shunts.

To correlate angiographic stenoses, pressure gradients, and intravascular Doppler velocity measurements, we studied 12 patients with failing hemodialysis shunts who were undergoing percutaneous transluminal angioplasty. Seven patients had a stenosis at the site of venous anastomosis, two had a stenosis of the central vein, and three had stenoses at both sites. The mean degree of angiographic stenosis was reduced by percutaneous transluminal angioplasty from 74 +/- 8% to 23 +/- 7% diameter, and the mean pressure gradient was reduced from 48 +/- 13 to 7 +/- 3 mm Hg. The proximal to distal peak systolic velocity ratio was significantly different before and after the angioplasty (3.3 +/- 1.4 and 1.6 +/- 0.6, respectively, P < 0.001). The lesion to proximal peak systolic velocity ratio was 2.5 +/- 0.8 before and 1.2 +/- 0.2 after percutaneous transluminal angioplasty (P < 0.001). Cutoff values of 1.9 for the proximal to distal velocity ratio and 1.5 for lesion to proximal velocity ratio were used to assess hemodynamic significance of lesions in our series. Velocity gradients derived from intravascular Doppler measurements correlate with angiographic and pressure measurements in failing hemodialysis shunts treated with percutaneous transluminal angioplasty. Further studies are needed to assess the exact role of these measurements in percutaneous revascularization procedures.     

彩色多普勒超声观测妊娠妇女肾动脉血流改变

应用彩色多普勒超声诊断仪对１５６例妊娠妇女及７６例正常妇女的肾动脉血流进行了观察，探讨了妊娠对肾动脉血流动力学的影响。结果显示：①无论正常或妊娠妇女，肾动脉血流速度及外周血管阻力在左右肾无明显差异。②妊娠后血流速度较非孕妇女增加，但外周血管阻力Ｓ／Ｄ、ＰＩ、ＲＩ与非孕妇女比较无明显变化。③随孕周增加，肾动脉血流速度在２８周前有增大趋势，孕２８周达高峰并维持高水平。肾动脉外周血管阻力在各孕周间无明显差异。研究证明，彩色多普勒血流检测可以准确了解肾脏血液动力学情况，有较高临床价值。