彩色多普勒超声检测不同运动方式对下肢静脉血流动力学的作用

目的选择能明显提高下肢静脉血流动力的有效运动方式，为预防下肢静脉血栓形成，提供理论依据。方法健康人128例，分成4种不同的运动组。使用高频彩超分别检测运动前后下肢静脉形态与血流动力学6项指标的变化。结果踮脚运动能显著增加股总静脉、浅静脉、深静脉及腘静脉的最大血流速度(Vmax)、时间速度积分面积(VTI)、血流量/min；其次为自主伸缩下肢运动。采用中频治疗仪、康复治疗仪的运动方式仅能有效改善腘静脉各血流参数。结论采用自主收缩小腿肌群的踮脚运动能有效改善下肢静脉血流动力学，有助于预防下肢静脉血栓形成。     

彩色多普勒超声在原发性下肢深静脉瓣功能不全中的应用

目的　应用彩色多普勒超声诊断原发性下肢深静脉瓣功能不全。方法　应用彩色多普勒超声检测了２２个病人（３６条腿）和１５个正常人（３０条腿）的下肢股浅静脉、腘静脉瓣及内径、彩色返流信号、血流频谱及时间平均流速（ＴＡＶ）。结果　２２个深静脉瓣功能不全的病人均有股浅静脉〔（９．３６±２．０） ｍ ｍ ｖｓ（５．３５±１．０） ｍ ｍ ; Ｐ＜ ０．００１〕和腘静脉〔（９．９０±２．３） ｍ ｍ ｖｓ （５．０６±１．４） ｍ ｍ , Ｐ＜ ０．０１〕的扩张; ＴＡＶ股浅静脉〔（３．９０±２．３） ｃｍ ／ｓ ｖｓ （６．５０±２．２） ｃｍ ／ｓ〕和腘静脉〔（２．７５±２１） ｃｍ ／ｓｖｓ （５．７５±２．３） ｃｍ ／ｓ, Ｐ＜ ０．００１〕明显减慢。在Ｖａｌｓａｌｖａ＇ｓ或平静呼吸时显示有彩色返流信号, 脉冲多普勒显示呈双向频谱, 其中, 股浅静脉瓣３例, 腘静脉瓣１４例, 双瓣１９例。正常组腘静脉瓣１例。二组差别有极显著意义。结论　彩色多普勒超声能明确瓣膜的返流的部位及返流程度, 诊断下肢深静脉瓣功能不全。对外科合理地选择手术方式及部位, 并在术后观察疗效。     

下肢动脉超声造影的初步研究

目的 探讨经静脉声学造影剂对下肢动脉彩色血流信号的增强作用,方法,19例患者分为2组;（1）正常组13例;（2）血管病变组6例,超声造影剂经左前臂浅静脉注射。结果 正常下肢动脉经造影剂增强后表现彩色血流信号增多,血流束增宽,4例股,国动脉闭塞者造影增强后管腔内仍无彩色血流信号,在闭塞管腔远侧,见3例胫前和1例胫后动脉内有彩色血流,上段有侧支血流进入,另2例患者胫前和颈后动脉彩色血流信号稀少,经造影增强后彩色血流信号增多并有充盈缺损,X线血管造影亦证实管腔有狭窄存在,结论 经静脉超声造影剂能够显著增强下肢动脉彩色血流信号,有助于肢血管病变的诊断。     

LEg venous oxygen saturation in the evaluation of intra-operative blood flow during arterial reconstructive surgery.

In twenty-four patients, undergoing a femoro-popliteal saphenous vein bypass graft for symptomatic atherosclerotic occlusion of the superficial femoral artery, oxygen saturation values for the femoral and popliteal veins were compared to the directly measured blood flows in the common femoral artery and in the bypass graft, respectively. Blood flow and venous oxygen saturation increased significantly after transfusion of 900 ml of blood. Pharmacological vasodilation caused a significant increase in blood flow both before and after transfusion, whereas the changes in venous oxygen saturation were significant only before blood transfusion. A close statistical relationship was found between initial femoral venous oxygen saturation and initial blood flow in the common femoral artery as well as between initial popliteal venous oxygen saturation and initial byapss blood flow. However, especially at low saturation values, the evaluation of blood flow was very uncertain. Whole leg and lower leg oxygen uptakes were not altered by intraoperative changes in blood volume. It is concluded that blood flow in the common femoral artery and the bypass graft can be roughly estimated from analysis of oxygen saturation in the femoral and popliteal veins, respectively. Furthermore, by determining leg venous oxygen saturation both before and after flow augmentation, induced by pharmacological vasodilation, a conception of the load on the vascular system may be obtained.     

糖尿病患者下肢动脉病变彩色多普勒检查的应用价值

目的探讨彩色多普勒检查，在糖尿病患者下肢动脉病变诊断中的应用价值。方法糖尿病组70例，非糖尿病组35例。分别应用彩色多普勒超声观察双侧股总动脉、股浅动脉、股深动脉、膪动脉、足背动脉的血管内径、内－中膜的厚度、收缩期最大峰值血流速度、舒张期末血流速度、搏动指数、阻力指数；观察血管内有无硬化斑块、有无完全性和不完全性动脉闭塞。结果糖尿病组较非糖尿病组动脉内膜增厚（P〈0.01），动脉硬化斑块发生率90％。各项血流参数提示，在股动脉糖尿病和非糖尿病组之间差异不显著（P〉0．05）；在胭动脉和足背动脉糖尿病组的PSV和EDV低于非糖尿病组，血流阻力指数明显高于非糖尿病组（P〈0．05），严重者发生下肢动脉不完全性或完全性闭塞。结论彩色多普勒超声检查可对糖尿病伴动脉硬化程度的评估提供客观依据。     

On the IVUS plaque volume error in coronary arteries when neglecting curvature

Plaque volume determined by common linear 3-D IVUS analysis systems will show under- or overestimation in curved vessel segments because these systems approximate the true 3-D transducer pull-back trajectory by a straight line. We developed a mathematical model that showed that the error is primarily dependent on the curvature of the pull-back trajectory and not on vessel tortuosity. Furthermore, we measured this error in vivo in the coronary arteries of 15 patients, comparing the plaque volume using a true 3-D reconstruction method with that of the linear approach. The in vivo plaque volume error ranged from 2.3% to −1.2% for 15 coronary segments with lengths ranging from 38.8 to 89.1 mm (62.2 ± 13 mm). The volume error introduced by linear 3-D IVUS analysis systems is dependent on the curvature of the pull-back trajectory. The error measured in vivo was small and inversely related to segment length.     

In vivo kinetics of microbubbles of SH U 508 A (Levovist): comparison with indocyanine green in rabbits

The aim of this study was to evaluate in vivo kinetics of microbubbles of SH U 508 A, in comparison with Indocyanine Green, a dye used as an indicator of blood flow. Microbubble kinetics were evaluated in various vessels (i.e., vena cava, aorta, renal artery, renal vein and portal vein) in rabbits after injection of SH U 508 A by measuring Doppler signals (n = 5). The kinetics of Indocyanine Green were evaluated by measuring absorbance using a photodiode (n = 5). Test substances (SH U 508 A 300 mg/mL and Indocyanine Green 1.25 mg/mL) were injected IV at a dose of 0.1 mL/kg B.W. Peak signal intensity was observed immediately after injection of SH U 508 A, followed by biphasic decay. The rates of biphasic decay were similar in all vessels. A second peak of the signal, which indicated recirculation of the microbubbles, was observed in the vena cava. The circulation and recirculation times of the microbubbles after injection of SH U 508 A were similar to that of Indocyanine Green. These findings suggest that the majority of SH U 508 A microbubbles circulate through the body similarly to blood flow, without retention, in the vasculature.     

彩色多普勒超声对高血压和糖尿病患者下肢动脉硬化特征的研究

目的比较高血压和糖尿病患者下肢动脉病变的分布及严重程度。方法对164例高血压患者及178例糖尿病患者进行下肢动脉检查（包括股动脉、胭动脉、胫前、后动脉及足背动脉）,观察二维超声表现及CDFI表现。结果糖尿病组与高血压组相比：股总动脉、股浅动脉、股深动脉粥样硬化斑块、中层钙化的发生率无显著性差异（p〉0．05）;胭动脉、胫前动脉、足背动脉中层钙化及胭动脉粥样硬化斑块的发生率则存在差异（p〈0．05）;胫前动脉、胫后动脉、足背动脉粥样硬化斑块、胫后动脉中层钙化的发生率差别非常显著（p〈0．01）;膝以上动脉狭窄、闭塞率无显著性差异（p〉0．05）,膝以下（包括胭动脉、胫前、后动脉、足背动脉）动脉狭窄、闭塞率则差别非常显著（p〈0．01）。结论糖尿病患者下肢膝以下小动脉的损害较高血压组更为严重。     

Noninvasive assessment of the viscoelasticity of peripheral arteries

Currently used methods of examining the mechanical properties of blood vessel walls are either indirect or invasive, or measure vessel diameter and pressure waveforms at different sites. We developed a noninvasive technique to assess the mechanical properties and viscoelasticity of peripheral arteries. The pressure-strain elastic modulus (Ep) and the viscoelastic properties (energy dissipation ratio, EDR) of the common carotid artery (CCA), brachial artery (BA), radial artery (RA) and dorsalis pedis artery (DPA) were determined by means of palpating pressure and diameter distension waveforms extracted from high-resolution ultrasonography. The methodology was validated in vitro using an elastic tube phantom, as well as in vivo. In vivo study in 10 healthy volunteers (mean age 22 y) showed that the pressure-diameter curves were nonlinear, with an inflection at about 85–90 mmHg, and routed clockwise with slight hysteresis. The CCA (n = 5) had a mean diameter of 6.74 mm and the pulsatile diameter distension was 12.2%. The Ep calculated at the CCA was 0.44 × 10⁶ dyne/cm² with an EDR of 7.18%. The BA, RA and DPA (n = 10) had mean diameters of 3.91 mm, 2.21 mm and 2.12 mm; arterial strains of 4.60%, 4.25% and 8.91%; mean Ep of 1.39, 1.45, 0.90 × 10⁶ dyne/cm²; and mean EDRs of 6.34%, 6.15% and 5.60%, respectively. The method presented is relatively simple to implement clinically and has potential as a new diagnostic tool for detecting local vascular changes.     

经静脉声学造影诊断下肢动脉病变的初步研究

目的：探讨经静脉声学造影诊断下肢动脉病变的应用价值,方法：12例患者接受造影检查,造影剂经左前臂静脉注射,结果：注射造影剂后,下肢动脉彩色血流信号增多,血流束增宽,8例股,Guo动脉得造影前闭塞段及其远侧血管均无彩色血流信号,造一闭塞段仍无彩色血流信号,但远侧2例胫前动脉和6例胫后动脉有细窄彩色血流束,并可见侧支血流汇入,另4例股,国动脉狭窄者,造影前3例胫前动脉和2例胫后动脉无彩色血流信号,但造影后仅2例胫产动脉无彩色血流信号,4例胫后动脉均有彩色血流,结论：经静脉超声造影有助于准确诊断下肢血管病变。     

彩色多普勒超声在下肢静脉病变中的诊断效率与误诊分析

目的评价彩色多普勒显像(CDI)对不同节段下肢静脉血栓、侧支循环形成及瓣膜功能不全的诊断效率。方法将80例患者90条静脉分为髂静脉段、股-腘静脉段、胫-腓静脉段共270个节段,并与X线静脉造影对照,分析CDI对各节段静脉血栓、侧支循环形成及瓣膜功能不全的诊断效率,分析漏、误诊原因。结果 CDI诊断髂静脉段、股-腘静脉段、胫-腓静脉段深静脉血栓、侧支循环形成、瓣膜功能不全的敏感度分别为83.33%(20/24)、94.59%(35/37)、77.78%(21/27)、66.67%(8/12)、84.09%(37/44);特异度分别为76.47%(13/17)、94.34%(50/53)、90.48%(57/63)、93.59%(73/78)、91.30%(42/46);准确率分别为80.49%(33/41)、94.44%(85/90)、77.78%(78/90)、90.00%(81/90)、87.78%(79/90);阳性预测值分别为83.33%(20/24)、92.11%(35/38)、86.67%(21/27)、61.54%(8/13)、90.24%(37/41)。髂静脉段血栓漏、误诊8条,股-腘静脉段血栓漏、误诊5条,均为急性、部分栓塞。胫-腓静脉段血栓漏、误诊12条,11例为急性、完全栓塞,1例为慢性、部分栓塞。结论 CDI诊断股-腘静脉段血栓的敏感度、特异度高于髂静脉、胫-腓静脉段。尽管CDI对侧支循环形成的敏感度和阳性预测值较低,但特异度和准确度较高。急性栓塞较易造成漏、误诊。     

Doppler indices in the umbilical arteries: influence of vessel curvature induced by bladder filling

Doppler indices are widely used to assess normal versus pathologic haemodynamics. In obstetrics, the assessment of abnormal values in some critical compartments, such as the umbilical arteries (UA), may be crucial in the clinical management of growth-restricted foetuses. It was recently proposed that the UA should be sampled in their perivesical portion (PVC), i.e., where they surround the foetal urinary bladder. However, measurements at this site could be biased by the degree of curvature of the vessel due to bladder filling. We investigated this possibility in vivo and in vitro, i.e., measurements on rubber tubes at different radii of curvature R_c. There was significant dependence of the Doppler indices A/B and PI on the vessel curvature and insonation angle; in fact, we recorded errors of about 25% when R_c was 10 times larger than the radius of the vessel and about 100% when R_c was five times larger than the radius of the vessel. Therefore, measurements of the UA at the PVC site should only be performed when the foetal bladder is empty. (E-mail: caterina.guiot@unito.it)     

超声评估下肢浅静脉手术后深静脉瓣膜功能变化

目的 应用超声评估下肢浅静脉手术改善深静脉瓣膜功能的程度及其影响因素.方法 60例住院治疗的下肢原发性深静脉瓣膜功能不全的患者(70条患肢),术前经彩色多普勒超声检查深静脉血流动力学指标,术后6个月对患者进行超声随访,比较手术前后深静脉瓣膜功能的改善程度.结果 下肢浅静脉手术后深静脉瓣膜功能的总体改善率为65.7%,股浅静脉和腘静脉的瓣膜功能亦均得到了改善,且二者在改善程度上没有差异.激光腔内闭合术与大隐静脉高位结扎剥脱术对深静脉反流的改善程度无差异.结论 超声检查可用于下肢浅静脉手术改善深静脉瓣膜功能的评估.     

In vivo time-dependent gene expression of cationic lipid-based emulsion as a stable and biocompatible non-viral gene carrier

To make stable and biocompatible non-viral gene carriers for therapeutic gene therapy, we developed a cationic lipid-based emulsion (CLE) prepared by an oil-in-water (O/W) emulsion method, wherein squalene oil was used as an oil core and the cationic lipid, 1,2-dioleoyl-sn-glycero-3-trimethylammonium-propane (DOTAP), was employed as an emulsifier. To evaluate in vivo characteristics such as toxicity and time-dependent gene expression, a bioluminescence reporter gene in pCMV-luc plasmid DNA was simply mixed with CLE in aqueous condition, resulting in a CLE/DNA complex. The CLE/DNA complex was optimized to form a compact and stable nano-sized particle by adding different amounts of plasmid DNA, and an optimal cationic lipid-to-DNA (C/D) weight ratio of 4 was identified. Freshly prepared CLE/DNA complex, with a C/D of 4, showed a high transfection efficiency and minimal cytotoxicity in vitro, compared to controls of a liposome (DOTAP)/DNA complex and a branched poly(ethyleneimine) (Mw = 25 kDa) (bPEI)/DNA complex, respectively. The in vivo characteristics of the CLE/DNA complex were evaluated after intravenous injection into Balb/c mice. Time-dependent gene expression data in vivo were obtained using a non-invasive, whole animal bioluminescence imaging system. These data showed that the CLE/DNA complex offered prolonged high-level gene expression for 1 week, particularly in the liver and spleen. On the other hand, the controls of DOTAP/DNA complex and bPEI/DNA complex showed a relatively lower gene expression, because of the unstable and toxic properties of the control carriers. Our in vivo gene expression data demonstrate the potential of the CLE/DNA complex as a non-viral gene carrier for in vivo gene delivery.     

Image-directed Doppler ultrasound in the diagnosis of lower-limb venous insufficiency

Ninety-eight legs in 73 patients were evaluated with image-directed Doppler ultrasound for suspected chronic venous insufficiency. Examinations of the entire venous system were performed to determine lumen patency and valvular competence. Reflux during Valsalva maneuver in the femoral and great saphenous vein, and, after release of distal compression in the popliteal vein, indicated valvular incompetence. Twenty limbs had normal veins; Baker's cysts were found in three. Superficial venous insufficiency was found in 25 cases. Deep reflux, either alone or in combination with superficial reflux, was the predominant pathological feature (53 legs). Photoplethys-mographic studies of the veins were performed on 24 limbs. Image-directed Doppler ultrasound was more successful in defining the exact site of venous incompetence and in detecting nonvenous pathology. By the combination of real-time imaging of the vein with gated Doppler sonography of flow, image-directed Doppler sonography is becoming the method of choice for the investigation of chronic venous insufficiency. © 1994 John Wiley & Sons, Inc.     

彩色多普勒超声诊断血管外膜囊肿

目的 观察血管外膜囊肿（CAD）的超声表现。方法 回顾性分析9例经手术后病理证实的CAD的超声声像图表现。结果 9例CAD中,7例单发,均见于腘动脉;2例多发,其中1例发生于股动脉,1例发生于髂外静脉。超声诊断正确7例,1例误诊为夹层动脉瘤伴血栓形成,1例误诊为腹股沟淋巴结肿大。声像图中CAD表现为囊性无回声区,与管壁关系密切,管腔局部可受压变细;发生于动脉者病变远心端收缩期峰速正常或相对减低;发生于静脉者病变处远心端回流速度缓慢。结论 彩色多普勒超声能够显示CAD形态、评估管腔受压程度,为诊断和术后随访提供有力依据。     

腘血管陷迫综合征超声表现及误诊原因

目的 分析腘血管陷迫综合征(popliteal vascular entrapment syndrome,PVES)超声表现及误诊原因、防范措施.方法 回顾性分析6例PVES的临床资料.结果 PVES 6例中超声检查误诊1例,误诊率16.7％.6例均表现为患肢间歇性跛行,超声检查可见腘动脉近段向内侧不同程度移位,腘动静...     

M型超声和脉冲多普勒超声检测外周血管的对比研究

目的 检测不同节段外周血管M型波形和脉冲多普勒血流频谱时间间隔的差异性，探讨超声评价外周血管压力和血流传导的关系。方法 35例健康成人，23例冠心病患者，应用M型超声和脉冲多普勒超声扫查主动脉（AO）、颈动脉（RCCA）、腋动脉（RAA）、肱动脉（RHA）、桡动脉（RRA）、股动脉（RFA）、腘动脉（RPA），获得M型曲线和多普勒血流频谱，同步连接心电图，计算Q波起始点与M型曲线波形起始点的时间间隔（ΔT1）以及Q波起始点与血流频谱起始点的时间间隔（ΔT2）。结果 健康成人脉冲多普勒方法检测上述动脉时间间隔增长速度RCCA/AO、RAA/AO、RHA/AO、RRA/AO、RFA/AO、RPA/AO，较M型超声方法检测值为大，上述各值比较均有显著性差异（P〈0.05），冠心病患者脉冲多普勒方法和M型超声检测上述动脉时间间隔增长速度无明显差异性（P〉0.05）。结论 健康成人M型波形时间间隔增长速度快于脉冲多普勒时间间隔增长速度，冠心病患者两种时间间隔增长速度无明显差异性，可能与动脉僵硬度有关。     

Ultrasonic enhancement of gene transfection in murine melanoma tumors

The enhancement of gene transfection by ultrasound (US) was evaluated in vitro and in vivo using the B16 mouse melanoma model. Cultured cells were either exposed in suspensions in vitro or implanted subcutaneously in female C57BL/6 mice for 10–14 days and, subsequently exposed, in vivo. For comparison to results with a luciferase plasmid, a reporter plasmid for green fluorescent protein (GFP) was used to evaluate transfection efficiency. US was supplied by a system, similar to a Dornier HM-3 lithotripter, that produced shock waves (SW) of 24.4 MPa peak positive and 5.2 MPa peak negative pressure amplitudes at the focus. The plasmids were mixed with the suspensions to achieve 20 μL mL⁻¹, or were injected intratumorally to provide 0.2 mg DNA per mL of tumor. Acoustic cavitation was promoted by retaining 0.2 mL of air in the 1.2-mL exposure chambers in vitro and by injecting air at 10% of tumor volume in vivo. In vitro, cell counts declined to 5.3% of shams after 800 SW exposure, with 1.4% of the cells expressing GFP after 2 days of culture. In vivo, 2 days after 400 SW exposure, viable-cell recovery from excised tumors was reduced to 4.2% of shams and cell transfection was enhanced by a factor of about 8, reaching 2.5% of cell counts (p < 0.005 in t-test). These results show that strong tumor ablation induced by US shock wave treatment can be coupled with simultaneous enhancement of gene transfection.     

A method to estimate wall shear rate with a clinical ultrasound scanner

A simple technique to estimate the wall shear rate in healthy arteries using a clinical ultrasound scanner has been developed. This method uses the theory of fully developed oscillatory flow together with a spectral Doppler trace and an estimate of mean arterial diameter. A method using color flow imaging was compared with the spectral Doppler method in vascular phantoms and found to have errors that were on average 35% greater. Differences from the theoretic value for the time averaged wall shear rate using the spectral Doppler method varied by artery: brachial −9 (1) %; carotid −7 (1) %; femoral −22 (4) %; and fetal aorta −17 (10) %. Test measurements obtained from one healthy volunteer demonstrated the feasibility of the technique in vivo. E-mail: (james.blake@ed.ac.uk)