Pulmonary embolism: comparison of gadolinium-enhanced MR angiography with contrast-enhanced spiral CT in a porcine model

RATIONALE AND OBJECTIVES: The purpose of this study was to compare gadolinium-enhanced magnetic resonance (MR) angiography with contrast material-enhanced computed tomography (CT) for the detection of small (4-5-mm) pulmonary emboli (PE), with a methacrylate cast of the porcine pulmonary vasculature used as the diagnostic standard. MATERIALS AND METHODS: In 15 anesthetized juvenile pigs, colored methacrylate beads (5.2 and 3.8 mm diameter-the size of segmental and subsegmental emboli in humans) were injected via the left external jugular vein. After embolization, MR angiographic and CT images were obtained. The pigs were killed, and the pulmonary arterial tree was cast in clear methacrylate, allowing direct visualization of emboli. Three readers reviewed CT and MR angiographic images independently and in random order. RESULTS: Forty-nine separate embolic sites were included in the statistical analysis. The mean sensitivity (and 95% confidence intervals) for CT and MR angiography, respectively, were 76% (68%-82%) and 82% (75%-88%) (P > .05); the mean positive predictive values, 92% (85%-96%) and 94% (88%-97%) (P > .05). In this porcine model, PE were usually seen as parenchymal perfusion defects (98%) with MR angiography and as occlusive emboli (100%) with CT. CONCLUSION: MR angiography is as sensitive as CT for the detection of small PE in a porcine model.     

螺旋CT肺动脉造影诊断肺栓塞的价值

本文报告经CT肺动脉造影(CT pulmonary angiography,CTPA)诊断的肺栓塞(pulmonary cmbolism,PE)18例，进行回顾性分析。以探讨CIPA的诊断价值及其扫描技术。     

64层螺旋CT血管成像在肺动脉栓塞中的诊断价值

目的:探讨64层螺旋CT血管成像在诊断肺动脉栓塞中的价值。方法:回顾性分析19例临床确诊为肺动脉栓塞的64层螺旋CT肺动脉成像资料,并用最大密度投影(MIP)、多平面重组(MPR)、容积再现(VR)等方法显示肺动脉。结果:19例患者中,其中左右肺动脉栓塞有8支,叶肺动脉栓塞27支,段及亚段肺动脉栓塞56支。偏心型41支,闭塞型38支,中央型8支,附壁环形型4支。结论:64层螺旋CT肺动脉成像可作为肺动脉栓塞诊断的首选方法。     

肺动脉栓塞病变螺旋CT诊断价值

肺动脉栓塞(pulmonary embolism,PE)早发现、早治疗是影响患者预后的关键,随着MSCT在心、肺大血管方面的成像技术越来越成熟,明显提高了肺小血管和血管内栓子的显示率[1～3].本文回顾性分析了我院2010年1月～2012年1月确诊的18例肺动脉栓塞治疗前后的临床资料,以其评价CT肺血管成像(MSCT pulmonary angiogram,MSCTPA)在肺动脉栓塞治疗前后中的临床价值.     

Pulmonary embolism in pregnant patients: a survey of practices and policies for CT pulmonary angiography

OBJECTIVE: We surveyed the practices and policies of the radiology departments of the Society of Thoracic Radiology members regarding the use of CT pulmonary angiography in pregnant patients suspected of having pulmonary embolism. MATERIALS AND METHODS: Surveys were mailed electronically to the 403 members of the Society of Thoracic Radiology (403 addresses). Respondents were asked to send one response from each institution or department. Information gathered included use of CT angiography in relation to ventilation-perfusion imaging in pregnant patients, written policies, informed consent procedures, and modifications of standard protocols for dose reduction. RESULTS: Fifty-seven members responded; 43 (75%) reported that they perform CT angiography in pregnant patients suspected of having pulmonary embolism. Of the 43 respondents who perform CT angiography in pregnant patients, 23 (53%) generally perform CT angiography as the initial study rather than ventilation-perfusion scanning, 26 (60%) require informed consent from the patient, seven (16%) have a written policy concerning CT angiography in pregnant patients, and 17 (40%) modify standard imaging protocols for pregnant patients. The most common modification for dose reduction is decreasing the scanning area along the z-axis. CONCLUSION: Most respondents perform CT angiography in pregnant patients suspected of having pulmonary embolism, but their policies and practices vary considerably.     

64层螺旋CT肺动脉造影在诊断肺栓塞中的应用

<正>肺动脉栓塞(pulmonary embolism,PE),简称肺栓塞,是由于内源性或外源性栓子堵塞肺动脉,引起肺循环障碍的临床和病理生理综合征,其中发生肺出血或坏死者称为肺梗死。栓子包括内源性栓子和外源性栓子,如血栓栓子、脂肪栓子、羊水栓子及     

Pulmonary embolism findings on chest radiographs and multislice spiral CT

Multislice spiral CT is becoming an increasingly important tool for diagnosing pulmonary embolism. However, in many instances, a chest radiograph is usually performed as a first-line examination. Many parenchymal, vascular, and other ancillary findings may be observed on both imaging modalities with a highly detailed depiction of abnormalities on multislice CT. A comprehensive review of chest radiograph findings is presented with side-by-side correlations of CT images reformatted mainly in the frontal plane.     

MSCT肺血管成像对肺动脉栓塞的诊断价值

目的:探讨多层螺旋CT肺血管成像对肺动脉栓塞的诊断价值.方法:对24例肺动脉栓塞病例行多层螺旋CT肺动脉成像检查,图像采用1.0mm层厚、0.7mm层间距和0.75mm层厚、0.5mm层间距进行重建,CTPA后处理采用容积再现(VRT)、最大密度投影(MIP)和多平面重建(MPR),对重建的图像进行对照分析、比较优缺点.结果:24例病例中,病变共累及76支肺动脉,其中,主肺动脉6支、肺叶动脉36支、肺段动脉27支、亚段动脉7支.肺动脉栓塞病变显示,1.0mm及0.75mm层厚重建无显著性差异意义.结论:多层螺旋CT肺动脉成像具有安全、快速、无创优点,对肺动脉栓塞诊断特异性强、敏感性高,可作为肺动脉栓塞的首选检查方法.     

64层螺旋CT肺血管造影在肺栓塞诊疗中的应用价值

目的 探讨64层螺旋CT在肺栓塞诊断及治疗中的指导作用.方法 63例患者均行64层螺旋CT肺血管造影(CTPA),并进行多种形式的图像重建结合轴位图像分析.结果 64层螺旋CTPA对63例患者肺动脉各级管腔内的栓子均明确显示,共累及肺动脉303支;图像分析结果伞部显示肺栓塞的直接征象为:主肺动脉和(或)左右肺叶、段、亚段血管腔内充盈缺损和血管阻塞;部分显示肺栓塞的间接征象为:马赛克征、右心房及右心室肥厚及扩张、肺动脉扩张、胸腔积液、肺不张及实变(肺梗死)等.62例患者经溶栓治疗后复查CTPA,其中,栓子完全消失者47例,栓子明显缩小者11例,溶栓治疗效果差者3例,考虑为慢性肺栓塞.结论 64层螺旋CTPA是临床最有效的诊断肺栓塞及溶栓后疗效评价的无创性方法之一.     

64层螺旋CT肺血管造影在肺栓塞诊疗中的应用价值

目的 探讨64层螺旋CT在肺栓塞诊断及治疗中的指导作用。方法 63例患者均行64层螺旋CT肺血管造影(CTPA),并进行多种形式的图像重建结合轴位图像分析。结果 64层螺旋CTPA对63例患者肺动脉各级管腔内的栓子均明确显示,共累及肺动脉303支;图像分析结果伞部显示肺栓塞的直接征象为:主肺动脉和(或)左右肺叶、段、亚段血管腔内充盈缺损和血管阻塞;部分显示肺栓塞的间接征象为:马赛克征、右心房及右心室肥厚及扩张、肺动脉扩张、胸腔积液、肺不张及实变(肺梗死)等。62例患者经溶栓治疗后复查CTPA,其中,栓子完全消失者47例,栓子明显缩小者11例,溶栓治疗效果差者3例,考虑为慢性肺栓塞。结论 64层螺旋CTPA是临床最有效的诊断肺栓塞及溶栓后疗效评价的无创性方法之一。     

16排螺旋CT血管造影在肺动脉栓塞诊断中的应用

目的探讨16排螺旋CT血管造影（MSCTA）在肺动脉栓塞（PE）诊断中的临床应用价值。方法8例临床疑诊PE患者行MSCTA检查,并将薄层数据行多平面重组（MPR）与容积重建（VR）。结果CT诊断PE8例,共35处肺动脉栓子,其中,段及段以上栓子26处,亚段及以下栓子9处。栓子显示为部分性充盈缺损,附壁性充盈缺损,中心性充盈缺损以及完全性充盈缺损。结论MSCTA能直观地显示肺动脉各级栓子的部位和形态,对临床治疗方案的选择及疗效评价有较高的应用价值。     

16层螺旋CT肺动脉造影对肺栓塞诊断的临床价值

目的:探讨16层螺旋CT肺血管造影术(MSCTPA)诊断肺动脉栓塞的临床价值。方法:对临床拟诊肺栓塞的46例患者行MSCTPA检查及后重建技术,后重建方法包括容积再现(VR)、多平面重建(MPR)、最大密度投影(MIP)。结果:46例共发现栓子698个,其中肺动脉主干4个,左右肺动脉41个,叶动脉114个,段及亚段动脉539个。直接征象:①)血管截断征,表现为肺动脉管腔完全闭塞;②轨道征,表现为腔内充盈缺损位于血管中央,周围有对比剂环绕;③偏心性充盈缺损,表现为管腔内不规则充盈缺损偏向管壁一侧,边缘欠光整;④附壁性充盈缺损。间接征象:①肺窗观察见局限性的血管纹理稀疏,呈"马赛克征";②肺梗死,表现为肺外围以胸膜为基底的楔形或条状实变影;③胸腔积液、肺动脉高压、右心室肥大以及心包积液等。结论:MSCTPA能对肺动脉栓塞作出准确诊断,是无创、快速、安全、敏感的检查方法,并可追踪复查,评估治疗效果。     

64层螺旋CT血管造影对肺动脉栓塞的临床诊断价值

目的探讨64层螺旋CT血管造影对肺动脉栓塞的临床诊断价值。方法 30例患者行肺动脉CTA检查,并采用多平面重建（MPR）对原始数据进行后处理。结果 30例均能显示肺栓塞的部位、范围及局部管腔狭窄程度,CT表现为肺动脉内不规则斑块状、附壁样缺损,周围有或无高密度对比剂包绕。结论 64层螺旋CT血管造影是临床诊断肺动脉栓塞最有效的无创性方法之一。     

Pulmonary fat embolism syndrome: CT findings in six patients

PURPOSE: Our purpose is to describe the CT findings in pulmonary fat embolism syndrome (FES). METHOD: Chest radiographs and CT scans of six patients with pulmonary FES were reviewed. Initial and follow-up CT findings were noted, and the extent of CT abnormalities was correlated with partial pressure of arterial oxygen (PaO2). RESULTS: Focal areas of consolidation or ground-glass opacity and nodules were seen in all patients, predominantly in the upper lobes of the lungs. Association between these opacities and pulmonary vessels was indicated in three patients. In the lower lobes of all patients, gravity-dependent opacities predominated. Diffuse ground-glass opacity was noted in five patients. Follow-up CT scans showed rapid improvement in three patients, but the gravity-dependent opacity progressed. The extent of CT abnormalities correlated positively with PaO2 (r = 0.8, p < 0.05). CONCLUSION: CT findings reflect the pathophysiology of this syndrome, which differs from that of simple capillary permeability pulmonary edema.     

Intracranial aneurysms: evaluation in 200 patients with spiral CT angiography

The goal of this study was to assess the usefulness of spiral CT angiography (CTA) with three- dimensional reconstructions in defining intracranial aneurysms, particularly around the Circle of Willis. Two hundred consecutive patients with angiographic and/or surgical correlation were studied between 1993 and 1998, with CTA performed on a GE HiSpeed unit and Windows workstation. The following clinical situations were evaluated: conventional CT suspicion of an aneurysm; follow-up of treated aneurysm remnants or of untreated aneurysms; subarachnoid haemorrhage (SAH) and negative angiography; family or past aneurysm history; and for improved definition of aneurysm anatomy. Spiral CTA detected 140 of 144 aneurysms, and an overall sensitivity of 97 %, including 30 of 32 aneurysms 3 mm or less in size. In 38 patients with SAH and negative angiography, CTA found six of the seven aneurysms finally diagnosed. There was no significant artefact in 17 of 23 patients (74 %) with clips. The specificity of CTA was 86 % with 8 false-positive cases. Spiral CTA is very useful in demonstrating intracranial aneurysms. Received: 13 April 1999 Revised: 22 March 2000 Accepted: 3 May 2000