A visual probe localization and calibration system for cost-effective computer-aided 3D ultrasound

The 3D ultrasound systems produce much better reproductions than 2D ultrasound, but their prohibitively high cost deprives many less affluent organization this benefit. This paper proposes using the conventional 2D ultrasound equipment readily available in most hospitals, along with a single conventional digital camera, to construct 3D ultrasound images. The proposed system applies computer vision to extract position information of the ultrasound probe while the scanning takes place. The probe, calibrated in order to calculate the offset of the ultrasound scan from the position of the marker attached to it, is used to scan a number of geometrical objects. Using the proposed system, the 3D volumes of the objects were successfully reconstructed. The system was tested in clinical situations where human body parts were scanned. The results presented, and confirmed by medical staff, are very encouraging for cost-effective implementation of computer-aided 3D ultrasound using a simple setup with 2D ultrasound equipment and a conventional digital camera.     

Line filtering for surgical tool localization in 3D ultrasound images

We present a method for automatic surgical tool localization in 3D ultrasound images based on line filtering, voxel classification and model fitting. This could possibly provide assistance for biopsy needle or micro-electrode insertion, or a robotic system performing this insertion. The line-filtering method is first used to enhance the contrast of the 3D ultrasound image, then a classifier is chosen to separate the tool voxels, in order to reduce the number of outliers. The last step is Random Sample Consensus (RANSAC) model fitting. Experimental results on several different polyvinyl alcohol (PVA) cryogel data sets demonstrate that the failure rate of the method proposed herein is improved by at least 86% compared to the model-fitting RANSAC algorithm with axis accuracy better than 1 mm, at the expense of only a modest increase in computational effort. The results of this experiment show that this system could be useful for clinical applications.     

Monoamniotic twins with one fetal anencephaly and cord entanglement diagnosed with three dimensional ultrasound at 14 weeks of gestation

A 29-year-old pregnant woman with parity 0-0-0-0 was diagnosed with monoamniotic twin pregnancy discordant for anencephaly at 14 weeks gestation. Umbilical cord entanglement, which is an important cause of fetal death in monoamniotic twins, was confirmed by three-dimensional ultrasound. Cesarean section was performed at 34 weeks of gestation, and the normal newborn infant was discharged without any complications. We report a case of monoamniotic twin pregnancy discordant for anencephaly and diagnosed with cord entanglement by three-dimensional ultrasound at 14 weeks of gestation, and now report it along with a literature review.     

应用三维超声断层成像技术产前诊断胎儿阴茎阴囊转位

目的 分析胎儿阴茎阴囊转位在三维超声断层成像（TUI）中的图像特征,评价TUI诊断胎儿阴茎阴囊转位的价值。方法 34例可疑为阴茎阴囊转位的胎儿,胎儿孕周为24 ～ 40周,平均孕周32.0周。分别应用二维超声和三维超声TUI技术进行诊断,将两种检查技术所得到的检查结果进行比较。结果 34例胎儿中,生后或尸检证实31例为阴茎阴囊转位,应用三维TUI技术诊断胎儿阴茎阴囊转位的准确度（93.94 %）比应用二维超声诊断的准确度（66.67 %）高;两种方法对于诊断胎儿阴茎阴囊转位的差异有统计学意义（P 〈 0.05）。结论 三维TUI技术在产前诊断胎儿阴茎阴囊转位上具有较高的临床应用价值。 更多还原     

A comparison of 3D ultrasound to MRI for the measurement and estimation of gastrocnemius muscle volume in adults and young people with and without cerebral palsy

Muscle volume (MV) is an important parameter for understanding muscle morphology and adaptations to training, growth and pathology. In this study, we assessed the validity of freehand 3D ultrasound (3DUS) for measuring medial gastrocnemius MV in adults, typically developing (TD) children and children with cerebral palsy (CP). We also assessed the validity between our direct measures of MV and estimates derived from anatomical cross sectional area (ACSA) and muscle length (ML), using previously outlined methods. The medial gastrocnemius of all groups was scanned with 3DUS and MRI. Images from both methods were digitized to derive MV, ACSA and ML. Measured MV was compared between methods and compared to estimated MV derived from recently published algorithms. MV had a mean difference of ?0.13% (standard error of estimate (SEE) = 2.23%, R² = 0.99) between MRI and 3DUS and 19.82% (SEE = 4.73% and R² = 0.99) and ?3.11% (SEE = 6.55%, R² = 0.99) mean differences between the measured and estimated MV from two methods of estimation. The 3DUS is a valid method for the measurement of MV in adults, TD children and those with CP. Estimation methods of MV may be useful in clinical practice, but require further replication on various populations and careful methodological consideration. Clin. Anat. 32:319–327, 2019. © 2018 Wiley Periodicals, Inc.     

Diagnosis of true umbilical cord knot

Introduction

Many abnormalities are observed in the morphology and pathology of the umbilical cord. The aim of the study was to assess the role of 3D sonography in pathology of true umbilical cord knots.

Material and methods

In our materials we observed 10 cases of true umbilical cord knots in a population of 2,864 deliveries. The 2-dimensional transverse scan of the umbilical cord was shown in 3- and 4-dimensional volume scan in order to get a precise image.

Results

Four knots were diagnosed prenatally, 3 knots were not diagnosed before the delivery and in the 3 remaining cases ultrasound examinations were not undertaken because the patients were in the course of delivery. In the pregnant subjects with diagnosed true umbilical cord knot once a week the Doppler blood flow indices were examined in the umbilical cord sections before and after the knot. In the three shown cases there were no signs of constriction or tightening of the knot. Four newborns were delivered spontaneously and five by caesarean section. In none of the cases was a pathological FHR trace an indication for emergency delivery.

Conclusions

Four-dimensional and Color Doppler examination is very important to diagnose a true umbilical cord. To make a precise diagnosis a longer observation of the abnormality is necessary and its repeated confirmation by color Doppler and power Doppler. This diagnosis requires strict monitoring of fetal wellbeing during pregnancy and the delivery. Perfection of true umbilical cord knot diagnoses may reduce sudden and unforeseen fetal distress.     

Rapid construction of a patient-specific torso model from 3D ultrasound for non-invasive imaging of cardiac electrophysiology

One of the main limitations in using inverse methods for non-invasively imaging cardiac electrical activity in a clinical setting is the difficulty in readily obtaining high-quality data sets to reconstruct accurately a patient-specific geometric model of the heart and torso. This issue was addressed by investigation into the feasibility of using a pseudo-3D ultrasound system and a hand-held laser scanner to reconstruct such a model. This information was collected in under 20 min prior to a catheter ablation or pacemaker study in the electrophysiology laboratory. Using the models created from these data, different activation field maps were computed using several different inverse methods. These were independently validated by comparison of the earliest site of activation with the physical location of the pacing electrodes, as determined from orthogonal fluoroscopy images. With an estimated average geometric error of approximately 8 mm, it was also possible to reconstruct the site of initial activation to within 17.3 mm and obtain a quantitatively realistic activation sequence. The study demonstrates that it is possible rapidly to construct a geometric model that can then be used non-invasively to reconstruct an activation field map of the heart.     

数字化原位子宫动脉血管3D可视化模型的构建及意义

目的探讨构建女性原位子宫动脉血管3D可视化模型和研究子宫动脉血管的结构特征。方法采用聚乙烯醇-氧化铈血管造影术进行2例女尸盆腔动脉血管灌注,X线平位摄影、64排螺旋CT扫描后采集数据,导入计算机Mimics10.01重建软件进行子宫动脉血管3D可视化模型构建,观察子宫动脉血管的形态及血供分布情况。结果①构建的子宫动脉血管三维模型图像清晰,管道饱满,立体空间感强,均能清晰地显示子宫动脉的4级以上血管,各级分支血管的形态、走行、分布及各血管间的吻合显影清晰,效果满意。2例子宫及附件无实质性病变,为正常子宫。②清晰显示子宫动脉血管网的构建特点:子宫动脉自主干依次发出膀胱支、输尿管支、上行支、下行支等分支动脉;上行支较粗呈弓状沿子宫体侧缘迂曲上行,至宫角处分为宫底支、输卵管支和卵巢支,主要向子宫体和子宫附件供血;下行支较细分布于宫颈及阴道上段,但分布于阴道的血管较少;子宫动脉通过其卵巢支与卵巢动脉相交通;同时子宫动脉的供血还存有着明显的同侧倾向,双侧子宫动脉在子宫的中轴线处有少量细小的交通支。结论采用聚乙烯醇-氧化铈血管造影术盆腔动脉血管灌注可构建理想的子宫动脉血管网3D可视化模型,为系统研究人子宫动脉血管网的形态结构和血供分布提供了血管解剖学基础。     

IVUSAngio Tool: A publicly available software for fast and accurate 3D reconstruction of coronary arteries

There is an ongoing research and clinical interest in the development of reliable and easily accessible software for the 3D reconstruction of coronary arteries. In this work, we present the architecture and validation of IVUSAngio Tool, an application which performs fast and accurate 3D reconstruction of the coronary arteries by using intravascular ultrasound (IVUS) and biplane angiography data. The 3D reconstruction is based on the fusion of the detected arterial boundaries in IVUS images with the 3D IVUS catheter path derived from the biplane angiography. The IVUSAngio Tool suite integrates all the intermediate processing and computational steps and provides a user-friendly interface. It also offers additional functionality, such as automatic selection of the end-diastolic IVUS images, semi-automatic and automatic IVUS segmentation, vascular morphometric measurements, graphical visualization of the 3D model and export in a format compatible with other computer-aided design applications. Our software was applied and validated in 31 human coronary arteries yielding quite promising results. Collectively, the use of IVUSAngio Tool significantly reduces the total processing time for 3D coronary reconstruction. IVUSAngio Tool is distributed as free software, publicly available to download and use.     

Primary pancreatic diffuse large B‐cell lymphoma diagnosed by endoscopic ultrasound guided FNAC: A rare entity

Primary pancreatic lymphoma (PPL) is an uncommon neoplasm which can clinico‐radiologically mimic carcinoma. But the management of these patients differs from that of a carcinoma. Endoscopic ultrasound (EUS) guided fine‐needle aspiration (FNA) serves as a potential tool to identify pancreatic lymphomas and thus prevent an invasive diagnostic test. This case report describes the presentation and diagnosis of primary pancreatic lymphoma. A 37‐year‐old female presented with nausea, vomiting with signs of icterus and elevated liver function test and Bilirubin. Abdominal computed tomography (CT) revealed a hypodense lesion in the head of the pancreas. EUS guided FNA was performed and cytological material was collected. The lesion was diagnosed as Non‐Hodgkin Lymphoma (NHL) and subtyped as diffuse large B‐cell lymphoma‐germinal centre (DLBCL‐GCB) base on immunohistochemistry on cell block. The patient was started on rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (RCHOP) regimen. EUS guided FNA along with ROSE, cell bock, and immunocytochemistry helps in the diagnosis of primary pancreatic lymphoma.     

GPU-accelerated 3D mipmap for real-time visualization of ultrasound volume data

Ultrasound volume rendering is an efficient method for visualizing the shape of fetuses in obstetrics and gynecology. However, in order to obtain high-quality ultrasound volume rendering, noise removal and coordinates conversion are essential prerequisites. Ultrasound data needs to undergo a noise filtering process; otherwise, artifacts and speckle noise cause quality degradation in the final images. Several two-dimensional (2D) noise filtering methods have been used to reduce this noise. However, these 2D filtering methods ignore relevant information in-between adjacent 2D-scanned images. Although three-dimensional (3D) noise filtering methods are used, they require more processing time than 2D-based methods. In addition, the sampling position in the ultrasonic volume rendering process has to be transformed between conical ultrasound coordinates and Cartesian coordinates. We propose a 3D-mipmap-based noise reduction method that uses graphics hardware, as a typical 3D mipmap requires less time to be generated and less storage capacity. In our method, we compare the density values of the corresponding points on consecutive mipmap levels and find the noise area using the difference in the density values. We also provide a noise detector for adaptively selecting the mipmap level using the difference of two mipmap levels. Our method can visualize 3D ultrasound data in real time with 3D noise filtering.     

三维超声影像导航机器人系统的临床应用

为了提高三维超声引导下微波消融治疗肝癌穿刺机器人系统的末端精度,本研究用指数积方法建立了穿刺机器人正运动学模型,设计了特殊神经网络标定方法,并对机器人末端位置进行了标定.标定实验结果表明,经过此种方法标定后的穿刺机器人,在手术常用工作空间内的末端位置精度提高100%以上.此系统已在北京301医院获得成功的临床实验应用,手术结果表明该系统可以准确定位病灶区域,精确放置手术器械,摆脱穿刺引导架的角度限制.介入治疗机器人实现了大角度准确穿刺并满足介入手术的需求,有效地提高了囊肿穿刺手术的治疗效果.     

Validity and reliability of a structured‐light 3D scanner and an ultrasound imaging system for measurements of facial skin thickness

Three‐dimensional (3 D)‐scanning‐based morphological studies of the face are commonly included in various clinical procedures. This study evaluated validity and reliability of a 3 D scanning system by comparing the ultrasound (US) imaging system versus the direct measurement of facial skin. The facial skin thickness at 19 landmarks was measured using the three different methods in 10 embalmed adult Korean cadavers. Skin thickness was first measured using the ultrasound device, then 3 D scanning of the facial skin surface was performed. After the skin on the left half of face was gently dissected, deviating slightly right of the midline, to separate it from the subcutaneous layer, and the harvested facial skin's thickness was measured directly using neck calipers. The dissected specimen was then scanned again, then the scanned images of undissected and dissected faces were superimposed using Morpheus Plastic Solution (version 3.0) software. Finally, the facial skin thickness was calculated from the superimposed images. The ICC value for the correlations between the 3 D scanning system and direct measurement showed excellent reliability (0.849, 95% confidence interval = 0.799–0.887). Bland‐Altman analysis showed a good level of agreement between the 3 D scanning system and direct measurement (bias = 0.49 ± 0.49 mm, mean±SD). These results demonstrate that the 3 D scanning system precisely reflects structural changes before and after skin dissection. Therefore, an in‐depth morphological study using this 3 D scanning system could provide depth data about the main anatomical structures of face, thereby providing crucial anatomical knowledge for utilization in various clinical applications. Clin. Anat. 30:878–886, 2017. © 2017 Wiley Periodicals, Inc.     

Freehand三维超声体数据重建的最新研究进展

Freehand三维超声成像系统因其扫描方式自由、能提供更大的成像视角和更高的图像分辨率等优点,比较符合医生习惯和手术室环境,成为近年来超声影像引导介入手术的主要研究方向。Freehand三维超声从一系列不规则的二维B超图像入手,重构器脏结构的三维体数据,并进行三维渲染显示。体数据重建是Freehand三维超声成像系统的关键技术,对提高重建图像质量有着重要的作用。对Freehand三维超声体数据的重建算法进行归纳和分类,比较分析其中的典型算法,最后对Freehand三维超声体数据重建算法的研究状况和未来的发展方向进行展望。     

乳腺典型髓样癌与非典型髓样癌的超声诊断分析

目的探讨高频彩色多普勒超声对乳腺髓样癌的诊断价值。方法 56例乳腺髓样癌患者,均为女性,年龄25～87岁,平均年龄50.92岁;其中典型髓样癌35例,非典型髓样癌21例。患者手术前行乳腺超声检查,先用灰阶超声观察肿块的部位、大小、形态、边界、内部回声、有无钙化、后方回声增强或衰减,再启用彩色多普勒血流显像(CDFI)检查肿块的血流信号,频谱多普勒分析肿块血流阻力指数(RI),最后检查腋窝淋巴结有无肿大。结果乳腺髓样癌发生于左侧乳腺者占57.14%,高于右侧乳腺的42.86%,但差异无统计学意义(P>0.05)。典型髓样癌最大径平均值为2.39cm,略小于非典型髓样癌的2.52cm(P>0.05)。与非典型髓样癌比较,典型髓样癌形态较规则、边界较清楚、内部回声较均匀,多伴后方回声增强,钙化较少见。乳腺髓样癌血液供应多较丰富,该组32例典型髓样癌、18例非典型髓样癌进行了CDFI检查,血流Ⅱ/Ⅲ级者分别占65.63%、61.11%(P>0.05),其中20例进行了多普勒频谱分析,RI>0.70。结论典型髓样癌与非典型髓样癌在肿块的边界、回声均匀与否,有无钙化及后方回声增强等超声表现明显不同,术前高频彩色多普勒超声检查具有重要诊断价值。     

三维运动分析系统动态校准新方法

本文用格子平板校准法在albavison ACAM50 3D运动动态分析系统下进行校准,并对照了其他的三维分析系统和校准方法。结果显示本方法和系统的精度远高于目前使用的系统和方法,具有很高的实验和应用价值。     

用于肝癌介入治疗的术中三维超声导航系统

目前,介入治疗越来越多地被应用到肝癌患者的治疗中,相对于传统手术而言,介入治疗是一种简单、安全、有效的治疗方法。由于超声图像具有实时性,其被广泛地应用到介入治疗手术过程的导航。但是,在二维超声引导下,手术过程中病灶区域靶点的定位以及手术器械的精确放置难以达到实践的要求。本研究描述了用于肝癌介入治疗术中三维超声导航系统,该系统不仅可以提高穿刺路径规划,而且能够跟踪穿刺针并且实时的切片图像。通过试验证明,该系统穿刺精度可控制在5mm之内。该系统的应用可以准确定位病灶区域,精确放置手术器械,提高了手术的效果。     

3D可视化联合3D打印在肝癌大部分肝切除术中的应用

目的:探讨基于3D重建系统软件的肝体积评估和3D可视化、3D打印辅助肝癌大部分肝切除术的应用价值。方法:将符合要求的肝癌行大部分肝切除术患者46例,随机分为观察组和对照组,每组23例。观察组（3D组）患者采用3D可视化技术和3D打印模型进行围手术期规划和指导,主要基于肝体积评估等术前规划和3D可视化分析、3D打印指导肝切除术手术;对照组（CT组）患者采用传统CT资料进行肝体积评估等术前规划、CT二维影像资料指导肝切除术。观察指标:虚拟切除肝体积、实际切除肝体积、残肝体积、标准残肝体积比、手术时间、术中出血量、术后并发症、患者满意度等。结果:3D组与CT组虚拟切除肝体积与实际切除肝体积、虚拟（术前）残肝体积与实际（术后）残肝体积比较,差异均无统计学意义（P>0.05）,相关性分析显示虚拟切除肝体积与实际切除肝体积呈正相关性（3D组r=0.990, P<0.001;CT组r=0.943, P<0.001）。3D组与CT组虚拟残肝体积比、实际残肝体积比比较,差异均无统计学意义（P>0.05）,且相关性分析显示呈正相关性（3D组r=0.931, P<0.001;CT组r=0.902, P<0.001)。3D组术中出血量少于CT组（P<0.05）,3D组患者满意度优于CT组（P<0.05）。两组患者手术时间、术后并发症等比较,差异无统计学意义（P>0.05）。结论:3D重建系统软件和CT软件在评估肝癌大部分肝切除术的肝体积均可行、准确,具有很好的临床应用价值,有助于肝切除术的安全实施。3D可视化联合3D打印在围手术规划可减少手术出血,提高患者满意度,在临床应用中具有潜在优势。