彩色多普勒在门静脉穿刺注药治疗肝癌中的应用

本文探讨了彩色多普勒在门静脉穿刺注药治疗肝癌中的应用价值。对15例原发性肝癌和1例继发性肝癌患者门静脉穿刺注药前后及注药过程中彩色多普勒的应用表明;注药前彩色多普勒对肝肿瘤病灶及门脉血流动力学的检查有助于本治疗适应证的选择;注药过程中的彩色多普勒应用,有助于提高静脉穿刺注药的准确性和观察药液在肝内的弥散;注药后彩色多普勒检查及其穿刺活检有助于对肝癌疗效的观察;超声引导下的门静脉穿刺导向化疗,作为肝癌综合治疗的方法之一,值得进一步探讨。     

彩色多普勒超声在大隐静脉射频闭合术后随访中的应用

目的 探讨不同类型大隐静脉曲张经射频闭合术后,二维及彩色血流显像对其的呈像特点及随访价值.方法 68例大隐静脉曲张行射频闭合术的患者（共90支血管）,于术前1周,术后1周、1个月、3个月、6个月、12个月行超声检查,观察其二维图像及彩色血流信号随时间的演变规律.结果 术后6～12个月73%～81%的大隐静脉成闭锁或血栓样物质形成,术后3个月 93%大隐静脉几乎无血流显示,术后12个月后又有4.4%再通.结论 超声检查在大隐静脉曲张射频闭合术后的随访中有重要的价值.     

Imaging of intracranial aneurysm by three-dimensional contrast enhanced duplex sonography—two case reports

We report two cases of intracranial aneurysms to give an impression of the use of three-dimensional (3-D) transcranial duplex sonography in combination with the application of a transpulmonary stable contrast agent. Data acquisition was performed with a free-hand scanning of the transducer (2 MHz) and a prototype of a new magnetic sensor system to track the spatial orientation of the ultrasound probe while scanning the volume of interest. The 3-D data were stored and afterwards 3-D reconstructions performed. Three-dimensional transcranial color duplex system with power Doppler mode showed an exact spatial orientation of the intracranial arteries. The three-dimensional system lets the reader retrospectively choose the section plane through the 3-D data set, and the reconstructions through the data set allowed us to localize aneurysms in both cases. The increased freedom of movement of the transducer allows the sonographer to maintain transducer contact with the skin, while offering the freedom to move the transducer as needed to remain on the acoustic window.     

Early ovarian cancer: 3-D power Doppler

Transvaginal sonography plays an important role in the assessment of the morphology of ovarian lesions. However, the accuracy of the technique is limited due to the significant number of false-positive results. Color Doppler imaging and pulsed Doppler spectral analysis enable evaluation of ovarian tumor blood flow, analysis of the distribution of blood vessels, and quantitative measurement of blood flow velocity waveforms. These parameters increase the sensitivity and specificity of ultrasound evaluation of ovarian tumors. Unfortunately, there is no consensus as to which Doppler parameters and cutoff values are the most predictive of malignancy. Three-dimensional (3-D) power Doppler ultrasound provides a new tool to evaluate features of tumor vascularity. Three-dimensional ultrasound and 3-D power Doppler imaging in patients with “positive” findings on standard ultrasound tests, which encompass annual gray-scale transvaginal sonography followed by transvaginal color Doppler ultrasound in selected cases, represent a novel approach for early and accurate detection of ovarian cancer through screening. Combined evaluations of morphology and neovascularity by 3-D power Doppler ultrasound may improve early detection of ovarian carcinoma. Contrast-enhanced 3-D power Doppler sonography facilitates visualization of adnexal tumor vessels, which may aid in differentiating benign from malignant adnexal lesions.     

能量多普勒显像与彩色多普勒显像诊断13 例肾动脉狭窄意义的探讨

目的 研究能量多普勒显像（ＰＤＩ）在中型动脉的显示效果。探讨超声无创性诊断肾动脉狭窄的可能性。方法 使用彩色多普勒血流显像（ＣＤＦＩ）、能量多普勒显像及脉冲多普勒频谱分析（ＰＷＤ）对经血管造影证实的１３例肾动脉狭窄病人进行研究。结果 ＰＤＩ能够更好地反映狭窄血管的真实形态,明显增加肾动脉的显示长度和血流的稳定性。减少检查时间。结论 结合使用ＰＷＤ及其他超声新技术,ＰＤＩ可以很好的用来筛选和诊断肾动     

肝脏肿瘤三维超声成像的临床意义

目的探讨彩色三维多普勒超声对肝脏实性占位病变形态、大小及内部血供的诊断价值.方法对常规灰阶超声显示有肝脏实性占位病变的患者28例,采用腹部彩色三维超声成像仪自由臂方式对肝脏病变处及其周围进行扫查取像,取样结束后在三维超声仪上进行脱机后处理,以病变处为中心,对X、Y、Z 3个互相垂直切面上的病变范围进行勾划,生成三维的肿瘤球体,计算程序可自动计算球体体积、内部血流容积及两者之比.结果肿瘤体积最大为117 cm3,最小为2.0 cm3.三维超声可显示肿瘤供给血管走行及其分支情况,并可透视肿瘤内部血管分布情况.部分病变在二维图像上显示为"晕环"、"绕行"的肿瘤周边血管,在三维重建后显示出"抱球征",展现血管全貌,进入肿瘤内部后呈现出"提篮征",发出多支小血管,显示了恶性肿瘤的血供特征.结论彩色三维超声可对肝脏实性占位性病变的形态、体积、周边及内部血供进行综合评价,丰富了超声诊断依据.     

Assessment of fetal breathing movements using three different ultrasound modalities

Twenty-five consecutive women in the third trimester of pregnancy were studied to determine the presence or absence of fetal breathing movements using three different ultrasound imaging techniques. Using real-time B-mode observation of the fetal trunk as the standard, image-directed pulsed wave Doppler insonation of the umbilical vein confirmed the presence of breathing movements with a sensitivity of 100% and the absence of breathing movements with a specificity of 100%. The sensitivity and specificity of color Doppler imaging of the fetal naso-and oropharynx for the presence or absence of fetal breathing movements were 96% and 100%, respectively. In the current study, the detection of fetal breathing movements by three different ultrasound modalities was virtually interchangeable. © 1995 John Wiley & Sons, Inc.     

Specific Ultrasound Data Acquisition for Tissue Motion and Strain Estimation: Initial Results

Ultrasound applications such as elastography can benefit from 3-D data acquisition and processing. In this article, we describe a specific ultrasound probe, designed to acquire series of three adjacent imaging planes over time. This data acquisition makes it possible to consider the out-of-plane motion that can occur at the central plane during medium scanning, and is proposed with the aim of improving the results of strain imaging. In this first study, experiments were conducted on phantoms, and controlled axial and elevational displacements were applied to the probe using a motorized system. Radiofrequency ultrasound data were acquired at a 40-MHz sampling frequency with an Ultrasonix ultrasound scanner, and processed using a 3-D motion estimation method. For each of the 2-D regions of interest of the central plane in pre-compression data, a 3-D search was run to determine its corresponding version in post-compression data, with this search taking into account the region-of-interest deformation model chosen. The results obtained with the proposed ultrasound data acquisition and strain estimation were compared with results from a classic approach and illustrate the improvement produced by considering the medium's local displacements in elevation, with notably an increase in the mean correlation coefficients achieved.     

Enhanced color flow imaging of breast cancer vasculature: continuous wave Doppler and three-dimensional display.

Two methods of potentially improving the detection and assessment of breast cancer vasculature by color flow Doppler ultrasonography were studied. Use of continuous wave (CW) Doppler imaging was one method evaluated by a comparison of system sensitivity to small vessel flow by continuous wave and pulsed Doppler methods. The second technique demonstrated color flow image acquisition and three-dimensional (3D) display. Six breast cancer patients were examined with both a color flow pulsed system and a CW Doppler system employing a hand-held transmitter-receiver pair with crossed-beam patterns. The CW unit consistently revealed more regions of tumor flow and multidirectional flow. Good 3D displays were achieved on larger pulsatile vessels, from images obtained during systole and selected for minimal noise.     

Freehand ultrasound elastography with a 3-D probe

This paper presents the first near-real-time freehand ultrasound elastography system using a (3-D) mechanical probe. Acquisition is complete within two sec, and only an additional 20 sec are required for generation of a full 3-D strain volume. The strain is axial, with estimates of lateral and elevational tissue movement used to increase the accuracy of the axial strain measurement. This is the first time all system components have been extended to 3-D, i.e., 3-D windows are used to track displacement, which is tracked in all directions, and 3-D kernels are used for least-squares gradient estimates. Normalization of the freehand 3-D strain data is also applied across the whole volume. The system is tested using a novel research 3-D radiofrequency (RF) system with real-time control over the stepper motor driving the ultrasound probe, and real-time streaming of RF ultrasound data. The paper proves the concept, rather than making significant comments on the achievable accuracy in 3-D, although we demonstrate that the high performance of the 2-D techniques that we extend appears to carry through to in-vitro and in-vivo 3-D data. The result is a fast and high-resolution 3-D image of normalized axial strain. (E-mail: gmt11@eng.cam.ac.uk).     

腔内射频闭合术治疗大隐静脉曲张3年超声随访结果

目的观察超声引导下腔内射频闭合术治疗大隐静脉曲张的3年临床疗效。方法对6例大隐静脉曲张患者的6条无深静脉及穿静脉功能不全的中至重度大隐静脉曲张患肢，在超声引导下行腔内射频闭合大隐静脉主干，术后2—4周及术后3年对治疗下肢行超声随访。结果6条曲张的大隐静脉均成功实施腔内射频闭合术，术后2—4周随访，患者下肢酸痛、酸胀、乏力和浅表静脉曲张均减轻；超声检查6条大隐静脉主干均闭塞，无反流。术后3年随访，除1例尚有轻度下肢乏力外，其余患者症状消失；超声检查发现5条治疗段大隐静脉主干部分或全部管段呈条索状实变，直径小于2．0mm，另一条大隐静脉主干明显变细，内径3．0mm，有少量反流信号。结论超声引导下腔内射频闭合术治疗大隐静脉曲张术后3年随访结果佳，值得进一步研究。     

Three-dimensional (3-D) ultrasonography for obtaining the four and five-chamber view: comparison with cross-sectional (2-D) fetal sonographic screening.

OBJECTIVES: To assess the ability of Doppler-gated 3-D fetal echocardiography to reconstruct and display specific cardiac structures routinely visualized during antenatal ultrasound in a population at low risk for cardiac anomalies. To determine whether any advantage is offered by 3-D sonographic cardiac examination over conventional sonographic fetal screening techniques. DESIGN: After routine two-dimensional sonographic examination, 3-D cardiac data were collected prospectively in 30 fetuses with gestational ages between 19 and 23 weeks from a low risk patient population. Basic echocardiographic key views were derived from 3-D data and selected for reconstruction and analysis. Four- and five-chamber views were rated and only those views judged to be well visualized were considered as positive results. RESULTS: The four- and five-chamber views were well visualized in all but one fetus using conventional 2-D imaging. Gated 3-D volume data sets enabled visualization of these structures in only 19 of 30 fetuses but provided additional structural depth and allowed a dynamic 3-D perspective of valvar morphology and ventricular wall motion. The right ventricular outflow tract was available from the 3-D volumes in 16 subjects. CONCLUSIONS: Considering the versatility of gated 3-D fetal cardiac imaging we believe that it may soon become an important component of fetal screening thus helping to retrieve standard cardiac cross sections when 2-D imaging is limited by lack of sonographer experience or sonographic windows. Diagnostically acceptable echocardiographic views were obtained more consistently with 2-D ultrasound than with 3-D volume data.     

Feasibility study: real-time 3-D ultrasound imaging of the brain

We tested the feasibility of real-time, 3-D ultrasound (US) imaging in the brain. The 3-D scanner uses a matrix phased-array transducer of 512 transmit channels and 256 receive channels operating at 2.5 MHz with a 15-mm diameter footprint. The real-time system scans a 65 degrees pyramid, producing up to 30 volumetric scans per second, and features up to five image planes as well as 3-D rendering, 3-D pulsed-wave and color Doppler. In a human subject, the real-time 3-D scans produced simultaneous transcranial horizontal (axial), coronal and sagittal image planes and real-time volume-rendered images of the gross anatomy of the brain. In a transcranial sheep model, we obtained real-time 3-D color flow Doppler scans and perfusion images using bolus injection of contrast agents into the internal carotid artery.     

High-intensity focused ultrasound ablation assisted using color Doppler imaging for the treatment of hepatocellular carcinomas

Purpose

We evaluated the usefulness of color Doppler flow imaging to compensate for the inadequate resolution of the ultrasound (US) monitoring during high-intensity focused ultrasound (HIFU) for the treatment of hepatocellular carcinoma (HCC).

Materials and methods

US-guided HIFU ablation assisted using color Doppler flow imaging was performed in 11 patients with small HCC (<3 lesions, <3 cm in diameter). The HIFU system (Chongqing Haifu Tech) was used under US guidance. Color Doppler sonographic studies were performed using an HIFU 6150S US imaging unit system and a 2.7-MHz electronic convex probe.

Results

The color Doppler images were used because of the influence of multi-reflections and the emergence of hyperecho. In 1 of the 11 patients, multi-reflections were responsible for the poor visualization of the tumor. In 10 cases, the tumor was poorly visualized because of the emergence of a hyperecho. In these cases, the ability to identify the original tumor location on the monitor by referencing the color Doppler images of the portal vein and the hepatic vein was very useful. HIFU treatments were successfully performed in all 11 patients with the assistance of color Doppler imaging.

Conclusion

Color Doppler imaging is useful for the treatment of HCC using HIFU, compensating for the occasionally poor visualization provided by B-mode conventional US imaging.     

Vein graft surveillance with scanhead tracking duplex ultrasound imaging: a preliminary report

A severe arterial occlusion in the leg usually is bypassed by implanting a saphenous vein harvested from the limb. Once implanted, the vein functions well but over time may develop stenoses that may lead to occlusion. In order to detect and correct the stenoses that may lead to graft failure, frequent surveillance of the vein graft is required. A new ultrasound imaging method was developed to display the panoramic view of the vein graft in combination with its blood flow velocity waveform for surveillance. The panoramic view is the projection (ray-casting) image of multiple B-mode images with sequential longitudinal view of the vein graft. The velocity waveform also is recorded along the vessel with pulsed Doppler ultrasound. The acquired images and waveforms from the ultrasound scanner are registered individually in three-dimensional space with an electromagnet-based position and orientation sensor located on the scanhead. A prominent point on the scar from the surgery is used as the fiducial mark for spatial registration, so that the same lesion in the vein graft can be tracked automatically at each visit for retrospective study.     

能量多普勒显像与彩色多普勒显像诊断13 例肾动脉狭窄意义的探讨

目的 研究能量多普勒显像(PDI) 在中型动脉的显示效果,探讨超声无创性诊断肾动脉狭窄的可能性。 方法 使用彩色多普勒血流显像(CDFI) 、能量多普勒显像及脉冲多普勒频谱分析(PWD) 对经血管造影证实的13 例 肾动脉狭窄病人进行研究。结果 PDI 能够更好地反映狭窄血管的真实形态,明显增加肾动脉的显示长度和血流的 稳定性,减少检查时间。结论 结合使用PWD 及其他超声新技术,PDI 可以很好的用来筛选和诊断肾动脉狭窄。     

Proof-of-Concept Study of a 3-D Ultrasound Scanner Used for Ankle Joint Assessment

Joint arthropathies often require continuous monitoring of the joint condition, typically performed using magnetic resonance (MR) or ultrasound (US) imaging. US imaging is often the preferred screening or diagnostic tool as it is fast and inexpensive. However, conventional 2-D US has limited capability to compare imaging results between examinations because of its operator dependence and challenges related to repeat imaging in the same location and orientation. Comparison between several imaging sessions is crucial to assess the interval progression of joint conditions. We propose a novel 3-D US scanner for ankle joint assessment that can partially overcome these issues by enabling 3-D imaging. Here, we (i) present the design of the 3-D US ankle scanner system, (ii) validate the geometric reconstruction accuracy of the system, (iii) provide preliminary images of healthy volunteer ankles and (iv) compare 3-D US imaging results with MR imaging. The 3-D ankle scanner consists of a tub filled with water, a linear US probe attached to the wall of the tub and a motorized unit that rotates the US probe 360° around the center of the tub. As the probe rotates, a 3-D US image is formed of the ankle of the patient positioned in the middle of the tub. US probe height, angle and distance from the tub center can be adjusted. The reconstruction accuracy of the system was validated in each of the coordinate directions at different probe angles using two test phantoms. A phantom consisting of numerous Ø200-µm nylon threads with known spacing and a metal rod with machined grooves was used for validation in the horizontal and vertical directions, respectively. The volumetric reconstruction accuracy validation was performed by imaging an agar phantom with two embedded spheres of known volumes and comparing the segmented sphere volume and surface area with the expected. Three-dimensional US and MR images of both ankles of five healthy volunteers were acquired. Distal tibia and proximal talus were segmented in both imaging modalities and the surfaces of these segmentations were compared using the 95% Hausdorff and mean surface distances. The observed mean linear measurement error in all the coordinate directions and over several probe angles was 2.98%. The mean measured volumetric measurement error was 3.45%. The volunteer study revealed useful features for joint assessment present in the 3-D ankle scanner images, such as joint spacing, distal tibia and proximal talus. The mean 95% Hausdorff and mean surface distances between segmentations in 3-D US and MR images were 5.68 ± 0.83 and 2.01 ± 0.30 mm, respectively. In this proof-of-concept study, the 3-D US ankle scanner enabled visualization of the ankle joint features that are useful for joint assessment.     

3-D Transcranial Ultrasound Imaging with Bilateral Phase Aberration Correction of Multiple Isoplanatic Patches: A Pilot Human Study with Microbubble Contrast Enhancement

With stroke currently the second-leading cause of death globally, and 87% of all strokes classified as ischemic, the development of a fast, accessible, cost-effective approach for imaging occlusive stroke could have a significant impact on health care outcomes and costs. Although clinical examination and standard computed tomography alone do not provide adequate information for understanding the complex temporal events that occur during an ischemic stroke, ultrasound imaging is well suited to the task of examining blood flow dynamics in real time and may allow for localization of a clot. A prototype bilateral 3-D ultrasound imaging system using two matrix array probes on either side of the head allows for correction of skull-induced aberration throughout two entire phased array imaging volumes. We investigated the feasibility of applying this custom correction technique in five healthy volunteers with Definity microbubble contrast enhancement. Subjects were scanned simultaneously via both temporal acoustic windows in 3-D color flow mode. The number of color flow voxels above a common threshold increased as a result of aberration correction in five of five subjects, with a mean increase of 33.9%. The percentage of large arteries visualized by 3-D color Doppler imaging increased from 46% without aberration correction to 60% with aberration correction.     

Ultrasonographic Imaging Features of Female Urethral and Peri-urethral Masses: A Retrospective Study of 95 Patients

The aim of this study was to assess the imaging features of urethral and peri-urethral masses on transvaginal or transperineal ultrasound (US) in a cohort of 95 women. In this retrospective study, medical records of 95 female patients with 98 asymptomatic or symptomatic urethral and peri-urethral masses were retrospectively reviewed. Data regarding patient demographic characteristics, symptoms, signs, imaging features on 2-D and 3-D transvaginal or transperineal US, diagnostic tests and physical and intra-operative findings were extracted. The US imaging features and clinicopathologic characteristics of each urethral or peri-urethral mass were compared. On ultrasound, 39 masses (in 39 patients) were diagnosed as urethral diverticula, which manifested mostly as complex cystic masses (24/39, 61.5%); 35 masses (in 33 patients) were diagnosed as para-urethral cysts, which manifested mostly as simple cystic masses (19/35, 54.3%); 13 hypo-echoic solid masses (in 12 patients) exhibiting blood flow signals on color Doppler imaging were diagnosed as urethral leiomyomas; hypo-echoic or heterogeneous solid masses (in 8 patients) exhibiting blood flow signals on color Doppler imaging were diagnosed as urethral caruncles, including one complicated by malignant transformation; solid masses with mixed echogenicity (in 2 patients) exhibiting blood flow signals on color Doppler imaging were diagnosed as urethral squamous cell carcinoma or adenocarcinoma, and a hypoechoic solid mass (in one patient) with blood-flow signals on color Doppler imaging was diagnosed as urethral condyloma associated with human papillomavirus infection. This study confirmed transvaginal or transperineal 2-D and 3-D ultrasonography to be a valid, non-invasive, cost-effective diagnostic modality for the differential diagnosis of urethral and periurethral masses.     

A 3-D Region-Growing Motion-Tracking Method for Ultrasound Elasticity Imaging

A 3-D region-growing motion-tracking (RGMT) method for ultrasound elasticity imaging is described. This 3-D RGMT method first estimates the displacements at a sparse subset of points, called seeds; uses an objective measure to determine, among those seeds, which displacement estimates to trust; and then performs RGMT in three dimensions to estimate displacements for the remaining points in the field. During the growing process in three dimensions, the displacement estimate at one grid point is employed to guide the displacement estimation of its neighboring points using a 3-D small search region. To test this algorithm, volumetric ultrasound radiofrequency echo data were acquired from one phantom and five in vivo human breasts. Displacement estimates obtained with the 3-D RGMT method were compared with a published 2-D RGMT method via motion-compensated cross-correlation (MCCC) of pre- and post-deformation radiofrequency echo signals. For data from experiments with the phantom, the MCCC values in the entire tracking region of interest averaged approximately 0.95, and the contrast-to-noise ratios averaged 4.6 for both tracking methods. For all five patients, the average MCCC values within the region of interest obtained with the 3-D RGMT were consistently higher than those obtained with the 2-D RGMT method. These results indicate that the 3-D RGMT algorithm is able to track displacements with increased accuracy and generate higher-quality 3-D elasticity images than the 2-D RGMT method.