New aspects in spinal diagnostics with 3-D computed tomography

Three-dimensional imaging in computer tomography (3-D CT) has been rendered feasible by the development of special software programs. On the basis of the data from 50 spinal CTs, 3-D reformations are made. The method has proved effective especially in complicated vertebral fractures. There are regular correlations between the plane of the fracture and the choice of the axis of rotation as well as the nature of the reformations. A 3-D reformation is frequently more appropriate than a coronary or a sagittal 2-D reformation. In destructions of vertebrae due to tumors, the extent of bone destruction and the altered position of the vertebrae in relation to each other can be imaged. 3-D computer tomograms do not provide fundamentally new diagnostic information, but the understanding of pathological topography is improved.     

The colovesical fistula in congenital pouch colon: a histologic study

Purpose

The aim of this study was to perform a detailed histopathologic examination of the terminal colonic pouch and the colovesical fistula (CVF) excised during surgical management of male patients with the more severe forms (types I/II) of congenital pouch colon (CPC) associated with anorectal agenesis.

Methods

From January 2005 to December 2006, 25 male patients with types I/II CPC underwent abdominal exploration with dissection of the terminal portion of the colonic pouch and associated CVF till the bladder, division-ligation of the fistula, and excision of the colonic pouch. In 6 of the 25 patients, a complete dissection of the fistula to the bladder was possible, and in them, the terminal portion of the colonic pouch and the CVF were subjected to detailed histopathologic examination. The 6 patients included 3 newborns in whom this surgery was performed as a primary procedure, and 3 patients aged 3 months, 15 months, and 2 years, respectively, in whom a window colostomy of the pouch had earlier been performed. After due processing, multiple sections from the specimens were stained using the routine H&E method and examined under the microscope under different magnifications.

Results

In 4 specimens, the epithelial lining of the CVF consisted of transitional stratified epithelium with underlying anal/urethral glands. In 2 specimens, obtained from patients 15 months and 2 years old, respectively, the lining was of nonkeratinizing, stratified squamous epithelium. Other findings included aganglionosis in the muscle layers (n = 2), submucosal and subserosal fibrosis (n = 1), and thickening of muscle layers in the fistulous portion, suggestive of the presence of an internal sphincter (n = 2).

Conclusions

The CVF in patients with types I/II CPC shows histologic features of the normal anorectal canal.     

The spectrum of colovesical fistula and diagnostic paradigm

BACKGROUND: Our experience with colovesical fistula (CVF) over a 12-year period was reviewed to clarify its clinical presentation and diagnostic confirmation. METHODS: Twelve patients with CVF were identified. Presenting symptoms, etiologic factors, diagnostic investigations, and subsequent treatment were reviewed. RESULTS: Underlying etiologies were diverticular disease (75%), colon cancer (16%), and bladder cancer (8%). Pneumaturia (77%) was the most common presentation, followed by urinary tract infections, dysuria and frequency (45%), fecaluria (36%), hematuria (22%), and orchitis (10%). The ability of various preoperative investigations to identify a CVF were: computed tomography (CT) (90%), barium enema (BE) (20%), and cystography (11%), whereas cystoscopy, intravenous pyelogram (IVP), and colonoscopy were nondiagnostic. All patients underwent single- or multiple-staged repair of the fistula. CONCLUSIONS: In patients with a suspected CVF, we recommend CT followed by a colonoscopy as a first-line investigation to rule out malignancy as a cause of CVF. Other modalities should only be used if the diagnosis is in doubt or additional information is needed to plan operative management.     

Three-dimensional computed tomographic angiography in lower extremity revascularization

To evaluate the role of three-dimensional computed tomographic angiography (3D-CT) in peripheral artery bypass surgery, 49 patients with chronic lower limb ischemia underwent 3D-CT before and after a bypass operation. 3D-CT had a sensitivity of 96.8%, a specificity of 95.0% and an overall accuracy of 96.1% for the diagnosis of arterial and graft stenosis or obstructions. The ability to observe the acquired images at any angle was very useful for assessing the implanted graft in both aortoiliac and infrainguinal bypasses. Although these images equally identified arterial stenosis, obstruction, and the anastomotic morphology of bypass grafts as well as conventional angiography, the diagnostic accuracy was not helpful in the small arteries and grafts. 3D-CT is a low-invasive imaging method that is sufficient for forming strategies for bypass operations. In aortofemoral or femoropopliteal bypass surgery, 3D-CT thus provides sufficient imaging accuracy for bypasses up to the popliteal artery below the knee in patients with chronic limb ischemia.     

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目的探讨多层螺旋CT(MSCT)平扫、增强并结合瘘管造影对肛瘘进行定位诊断的临床应用价值。方法2004年7月至2006年5月间温州医学院附属第一医院对32例临床疑诊为肛瘘的病人使用16层螺旋CT扫描和瘘管造影。原始图像采用多平面重建(MPR)和容积重建(VR)技术进行三维重建,后处理图像由放射科专业医生完成。将术前获取的影像学资料与显微肛瘘手术和随访结果进行比较。结果MSCT上4例未发现肛瘘,5例为单纯性肛瘘,23例为复杂性肛瘘,均经过手术证实,肛肠专科检查将8例复杂性肛瘘误诊为单纯性肛瘘。MSCT上低位肛瘘6例,高位肛瘘22例,均经过手术证实,其中肛肠专科检查将8例高位肛瘘误诊为低位肛瘘,MSCT上3例括约肌外瘘误诊为括约肌上瘘。MSCT对术前内口、支管、脓腔评价的准确率分别为62.1%、89.3%、100.0%。MSCT后处理重建技术中,MPR包括曲面重建(CPR)可清晰显示瘘管的具体位置及其与肛管内外括约肌、肛提肌的关系,VR能三维再现瘘管的形态和走行特点。结论MSCT平扫、增强并结合瘘管造影是一种有效而可靠的对肛瘘进行定位诊断的检查方法,可以为手术提供有效依据。     

计算机三维重现兔先天性尿道下裂包皮血管

目的探寻先天性尿道下裂阴茎包皮血管变异的规律，计算机重现变异血管的三维立体构像。方法新西兰兔服用非那雄胺构建尿道下裂动物模型，阴茎组织连续切片，HE染色，显微镜下数码成像生成JPG格式图像，photoshop7．0软件及3Dmax8．0软件平台重建正常及变异阴茎血管的三维立体构像。结果采用非那雄胺成功构建了尿道下裂兔模型，根据阴茎外观形念分为阴茎头型、阴茎体型和阴囊会阴型尿道下裂。计算机三维立体构像可见正常包皮血管呈单支主干型，阴茎头型及阴茎体型尿道下裂包皮血管呈双支主干型，阴囊会阴型尿道下裂包皮血管呈网状无主干型。结论非那雄胺可以构建稳定兔先天性尿道下裂模型，正常包皮与尿道下裂包皮血管分布存在差别，不同类型尿道下裂之间包皮血管立体构像不同。     

A radiologic classification of talocalcaneal coalitions based on 3D reconstruction

Purpose  

Talocalcaneal coalitions can be difficult to detect on plain radiographs, despite obvious clinical findings. The purpose of this study is two-fold: (1) to delineate the benefits of thin-cut computed tomography (CT) and 3D reconstructions and (2) to develop a classification scheme for talocalcaneal coalitions that will provide valuable information for surgical planning.     

螺旋CT三维重建成像在先天性高肩胛症手术方式选择中的作用

[目的]探讨螺旋CT三维重建技术在先天性高肩胛症分度和手术方式选择中的作用。[方法]22例先天性高肩胛症术前应用螺旋CT对病变部位进行扫描并三维重建，测量以肩胛骨肩胛冈内侧缘为参照点，两侧肩胛骨高度差。根据测量结果依据Cavendish分度将其分类，并根据三维重建成像选择不同的矫形手术术式。[结果]本组22例病人，随访2—4年，外观及功能均有不同程度的改善，未出现神经、血管和椎体等的损伤。[结论]根据螺旋CT扫描和三维重建检查结果，术前即可直观的明确先天性高肩胛症的病变程度，相互关系，伴发畸形，患侧肩胛骨与正常对侧肩胛骨的外观差异等，便于手术操作方案的制定，避免了手术操作的盲目性，减少医源性并发症的发生。     

A new 3-D laparoscope in gastrointestinal surgery

This study was set up to compare three-dimensional imaging of a new three-dimensional laparoscope with two-dimensional imaging in the inanimate and clinical settings. In the clinical setting the laparoscope was used in a total of 50 different laparoscopic operations. It provided excellent depth perception, definition, and resolution. The relationships of structures were more easily defined, and instrument manipulation was easier, doing away with the need for touch and feel to determine instrument position. Three-D imaging made cannulation of the cystic duct for cholangiography or with a flexible choledochoscope easier.In the inanimate setting basic simple tasks took the same time in 2-D as in 3-D, whereas a more complicated procedure of passing a needle and suture through a series of hoops was 25% faster when performed in 3-D compared to 2-D. Three-D imaging may reduce operative time for laparoscopic procedures, particularly the more complicated operations.     

Use of multidetector computed tomography for evaluating coronary artery disease in patients undergoing dialysis

Aim: Cardiovascular disease is the most common cause of death in patients undergoing dialysis. The accuracy of multidetector computed tomography (MDCT) for detecting coronary disease has not been determined, and little information is available regarding the performance of MDCT in patients undergoing dialysis. Methods: Twenty‐nine patients undergoing dialysis were analyzed and MDCT and coronary angiography (CAng) were performed consecutively. The coronary arteries were divided into four segments for analysis. We compared the significant stenosis lesions (≥50% luminal narrowing) identified by MDCT with those found by CAng. The total coronary artery calcium (CAC) score was determined by summing the individual lesion scores from each of the coronary branches. Results: One hundred and sixteen coronary artery branches in 29 patients were analyzed. The sensitivity, specificity, and positive and negative predictive values of MDCT for detecting significant coronary artery stenosis (≥50% stenosis) were 68%, 94%, 71% and 93%, respectively. The CAC scores were significantly higher in subjects with coronary artery disease (CAD) (514.0 ± 493.6 vs 254.3 ± 375.3, P = 0.05). The severe CAC score (>500) was related to the presence of significant CAD (P = 0.05) and the sensitivity and specificity for detecting significant CAD were 50% and 80%, respectively. Conclusion: MDCT is a useful and non‐invasive approach for detecting or excluding CAD in patients undergoing dialysis.     

基于CT影像组学胰十二指肠切除术后胰瘘风险预测模型及其价值

目的 探讨基于CT影像组学模型术前预测胰十二指肠切除术后胰瘘(POPF)的应用价值。方法 回顾性分析106例接受胰十二指肠切除术患者的临床及腹部CT资料,其中POPF(+)组36例,POPF(-)组70例。采用ITAK-SNAP软件勾画CT图像感兴趣区域(ROI),Python程序的radiomics包进行影像组学特征提取,使用最小绝对收缩和选择算子(least absolute shrinkage and selection operator,LASSO)回归进一步筛选特征、建立影像组学评分(Rad-score),构建影像组学预测模型。然后将临床特征、Rad-score纳入多因素Logistic回归分析,筛选出POPF发生的独立危险因素,构建临床预测模型以及联合影像学组学特征的混合模型。最后采用受试者工作特征曲线(ROC)评估不同模型的预测效能。结果 共筛选出7个非零影像组学特征并建立了Rad-score。BMI、胰管扩张及Rad-score均是发生POPF的独立危险因素。影像组学预测模型、临床特征预测模型及混合预测模型预测POPF的曲线下面积(AUC)为分别为0.72、0.69、0...     

一种新的三维复杂曲面测量算法分析

提出了一种全新的非接触式三维复杂曲面测量方法，利用片激光源产生的光切面在被测物表面形成一个封闭光带，并使光带同时成像在3个互成固定角度的CCD摄像机中.经过CCD摄像机像面和光切平面之间的空间映射变换及图象处理后,可一次获得被测物的某一个截面的二维轮廓信息.随着测量系统以固定的间距沿垂直于光切面的方向步进测量，最终以被测物表面的大量离散点数据非常近似地获得了整个被测物的三维曲面信息.     

Validation of computed tomographic lung densitometry for monitoring emphysema in alpha1-antitrypsin deficiency

BACKGROUND: Lung densitometry derived from computed tomographic images offers an opportunity to quantify emphysema non-invasively, but a pathological standard cannot be applied to validate its use in longitudinal monitoring studies. Consequently, forced expiratory volume in 1 second (FEV1) remains the standard against which new methods must be judged. We related progression of densitometry (15th percentile point and voxel index, threshold -950 Hounsfield units) to disease stage and FEV1 decline in two studies of subjects with alpha1-antitrypsin deficiency (PiZ). METHODS: Consistency of progression, measured using densitometry and FEV1, was assessed in relation to disease stage in a 2 year study of 74 subjects grouped according to the FEV1 criteria employed in the GOLD guidelines. In the second study of a subgroup of subjects with extended data (n=34), summary statistics were applied to measurements performed annually over 3 years and the rate of progression of densitometry was related to FEV1 decline. RESULTS: The progression of percentile point was consistent across a wide spectrum of disease severity, but voxel index progression varied in association with disease stage (p=0.004). In the second study, FEV1 decline correlated with progression of lung densitometry (percentile point: rS=0.527, p=0.001; voxel index: rS=-0.398, p=0.012). CONCLUSIONS: 15th percentile point is a more consistent measure of lung density loss across a wide range of physiological impairment than voxel index. However, both methods are valid for use in longitudinal and interventional studies in which emphysema is the major outcome target.     

MSCT及后处理技术诊断食管闭锁并气管食管瘘

目的探讨MSCT及后处理技术诊断先天性食管闭锁合并气管食管瘘(EA-TEF)的价值。方法收集8例临床疑诊为EA-TEF的新生儿,于手术前行食管造影及MSCT扫描并进行重建,重建方法包括MPR、MinIP、VR等;将术前MSCT诊断结果与手术结果进行对照研究。结果 8例中,1例为EA-TEFⅠ型,7例为Ⅲ型(其中Ⅲa型4例,Ⅲb型3例);5例伴有其他先天性畸形。利用MPR、VR重建图像测得的闭锁食管上下盲端的距离与手术结果基本相符,7例仿真内镜图像能明确显示瘘管开口。结论 MSCT及其后处理技术可以准确诊断EA-TEF并进行分型,显示闭锁食管上下盲端情况及气管-食管瘘口位置可靠,还能显示肺部病变及其他伴随畸形。