主动脉夹层的MRI诊断

目的：评价MPd对主动脉夹层的诊断价值。方法：回顾性分析7例主动脉夹层的MRI表现。采用Siemens Impact 1．0T CTMR成像仪，行轴位、冠状位及平行主动脉弓斜位扫描，SE序列T1WI、T2WI成像。扫描范围自肺尖至左右髂血管分叉处。结果：按DeBakey分型：Ⅰ型2例，Ⅱ型2例，Ⅲ型3例。按Stanford分型：A型2例，B型5例。MPI表现：直接征象：①主动脉管腔内的内膜片，7例显示内膜片呈线样螺旋状稍高信号；②双腔主动脉，7例显示真腔较假腔小，呈三角形或半圆形，假腔宽大，信号较真腔高；③1例显示内膜破口。间接征象：①主动脉增宽5例；②胸腔积液3例，呈长T1长T2信号，1例腹膜后渗出，表现为肾筋膜增厚；③累及动脉瓣和主要大血管分支，2例主动脉瓣受累，2例累及头臂血管，1例腹腔动脉受累，2例累及肾动脉，2例累及髂血管。受累血管内信号增高，内壁不光整。结论：主动脉夹层具有典型MPI征象。MRI对主动脉夹层的诊断具有较高的敏感性和特异性，是一种无创、安全、有效的检查方法。     

多层螺旋CT在不典型主动脉夹层诊治中的应用

目的:探讨多层螺旋CT(MSCT)在主动脉不典型夹层(AIH)诊断和治疗中的应用价值。方法:对临床疑似主动脉病变的患者行MSCT增强前后扫描,发现17例AIH,并对保守治疗15-30天后的CT图像进行比较。结果:17例AIH,A型4例,B型13例。CT表现:①主动脉壁环形或新月形增厚>5mm,平扫血肿高密度5例,等密度3例,低密度9例,增强后均表现为充盈缺损;②6例见钙化的内膜内移;③12例并发胸腔积液或心包积液;④经内科保守治疗后,8例完全吸收,6例部分吸收,3例无明显变化。结论:MSCT能清楚显示AIH的部位、范围及并发症,是诊断AIH有效的首选影像学检查方法,并对治疗后AIH的转归提供影像学信息。     

Time-resolved CT angiography in aortic dissection

Objectives

We performed this study to assess feasibility and additional diagnostic value of time-resolved CT angiography of the entire aorta in patients with aortic dissection.

Materials and methods

14 consecutive patients with known or suspected aortic dissection (aged 60 ± 9 years) referred for aortic CT angiography were scanned on a dual-source CT scanner (Somatom Definition Flash; Siemens, Forchheim, Germany) using a shuttle mode for multiphasic image acquisition (range 48 cm, time resolution 6 s, 6 phases, 100 kV, 110 mAs/rot). Effective radiation doses were calculated from recorded dose length products. For all phases, CT densities were measured in the aortic lumen and renal parenchyma. From the multiphasic data, 3 phases corresponding to a triphasic standard CT protocol, served as a reference and were compared against findings from the time-resolved datasets.

Results

Mean effective radiation dose was 27.7 ± 3.5 mSv. CT density of the true lumen peaked at 355 ± 53 HU. Compared to the simulated triphasic protocol, time-resolved CT angiography added diagnostic information regarding a number of important findings: the enhancement delay between true and false lumen (n = 14); the degree of membrane oscillation (n = 14); the perfusion delay in arteries originating from the false lumen (n = 9). Other additional information included true lumen collapse (n = 4), quantitative assessment of renal perfusion asymmetry (n = 2), and dynamic occlusion of aortic branches (n = 2). In 3/14 patients (21%), these additional findings of the multiphasic protocol altered patient management.

Conclusions

Multiphasic, time-resolved CT angiography covering the entire aorta is feasible at a reasonable effective radiation dose and adds significant diagnostic information with therapeutic consequences in patients with aortic dissection.     

不典型主动脉夹层的多层螺旋CT诊断价值

目的:回顾性分析不典型主动脉夹层(atypical aortic dissection,AAD)的CT表现,探讨螺旋CT诊断AAD的价值。方法:25例AAD患者,全部行平扫及增强扫描,并结合多平面重组、曲面重组等方法显示AAD及穿透溃疡,根据Stan-ford分类法分型。结果:25例AAD,A型7例,B型18例。主要CT表现:主动脉壁呈新月型或环形增厚,无内膜破裂形成的双腔主动脉征象,增强扫描假腔无强化。内膜钙化向内移位7例,穿透性溃疡征3例。并发心包、纵隔及胸腔积液和积血共10例。经内科保守治疗后,6例完全吸收,3例部分不典型吸收,2例无明显变化。结论:螺旋CT清楚显示夹层的部位、范围及并发症,可作为主动脉夹层的首选检查及随访方法。     

Aortic dissection presenting as acute pancreatitis: CT diagnosis

A 42-year-old male developed epigastric pain and elevation of serum amylase of 2045 U/L. A contrast-enhanced abddominal CT disclosed inflammatory changes involving the pancreas and peripancreatic tissues and findings indicative of aortic dissection. The possibility of aortic dissection should be considered in the management of patients with acute pancreatitis.     

64层螺旋CT血管成像在主动脉夹层诊断中的临床价值

目的:探讨64层螺旋CT血管成像(CTA)在主动脉夹层(AD)诊断及术前评价中的应用价值。方法:58例连续性AD患者行64层螺旋CTA,对所有数据进行MPR、MIP、VR等重建分析。结果:CTA结果显示依据DeBakey分类法,Ⅰ型夹层14例,Ⅱ型2例,Ⅲ型42例。所有患者均存在明确的撕裂内膜片及真假腔,动脉期真腔平均CT值较假腔高,差异有统计学意义(P=0.000<0.05)。所有患者均明确显示了初始破口的位置,55例显示了一个或多个再破口,3例Ⅲ型患者未显示再破口。39例Ⅲ型患者初始破口位于主动脉弓降部或降胸主动脉近端,其近端瘤颈长度、宽度分别为0.4～10.8cm(平均3.5cm)、2.2～3.6cm(平均2.8cm),瘤体最大径为3.2～9.2cm(平均5.4cm)。图像准确显示了所有患者主动脉重要分支受累以及假腔内血栓形成情况。结论:64层螺旋CT血管成像具有无创、快速、准确性高等优点,是主动脉夹层诊断及术前评价的可靠影像学检查方法之一。     

螺旋CT血管造影术在夹层动脉瘤诊断中的应用

目的评价螺旋CT血管造影技术在夹层动脉瘤诊断中的临床应用价值。方法21例夹层动脉瘤行螺旋CT连续容积增强扫描，并将获得的数据传至工作站行三维重建，结合横断面及三维重建图像进行分析。结果根据Debakey分型，De．bakeyⅠ型10例，DebakeyⅢ型11例，两型中不典型夹层各2例。典型夹层动脉瘤的CT征象主要是分离移位的内膜、真假腔、主动脉壁增厚、钙化、主动脉不规则扩张；不典型主动脉夹层动脉瘤的征象为主动脉壁呈半月状或环状增厚，伴或不伴有内膜钙化内移。结论螺旋CT血管造影检查在诊断主动脉夹层动脉瘤中是一种安全有效的便于治疗后观察对比的方法。     

Pitfalls in the diagnosis of thoracic aortic dissection at CT angiography.

Two hundred seventy-five computed tomographic (CT) angiograms of the thoracic aorta were obtained over a period of approximately 4 years in patients with suspected or known aortic dissection. In all cases, unenhanced images were initially obtained, followed by contrast material-enhanced images. A variety of pitfalls were encountered that mimicked aortic dissection. These pitfalls were attributable to technical factors (eg, improper timing of contrast material administration relative to image acquisition); streak artifacts generated by high-attenuation material, high-contrast interfaces, or cardiac motion; periaortic structures (eg, aortic arch branches, mediastinal veins, pericardial recess, thymus, atelectasis, pleural thickening or effusion adjacent to the aorta); aortic wall motion and normal aortic sinuses; aortic variations such as congenital ductus diverticulum and acquired aortic aneurysm with thrombus; and penetrating atherosclerotic ulcer. Although several of these pitfalls are easy to recognize and therefore unlikely to present a diagnostic problem, others are potentially confusing. Familiarity with these common pitfalls, coupled with a knowledge of normal intrathoracic anatomy, will facilitate recognition of true aortic dissection and help avoid misdiagnosis at thoracic aortic CT angiography.     

Mesenteric panniculitis: findings on CT, MRI, and angiography case report

The computed tomography (CT), magnetic resonance (MR), and angiographic features of a case of mesenteric panniculitis are presented. The MR characteristics of this rare disorder have not previously been reported. The value of MR in arriving at the preoperative diagnosis of this disorder is discussed.     

螺旋CT血管造影及三维重建在主动脉夹层诊断中的应用

目的:评价螺旋CT血管造影(SCTA)及三维重建在主动脉夹层诊断中的临床应用。方法:对21例主动脉夹层患者进行了SCTA成像及三维重建,并与手术及血管造影对照。结果:SCTA能清楚显示主动脉夹层病变及其复杂的解剖关系,如双腔、内膜片及累及的范围等。与血管造影及手术对照,SCTA的诊断符合率达100％。结论:SCTA二维与三维重建的联合应用,有助于主动脉夹层的诊断并可指导手术,且有望取代传统血管造影。     

Spiral CT aortography: an efficient technique for the diagnosis of traumatic aortic injury

The objective of this study was to assess the efficiency of spiral CT (SCT) aortography for diagnosing acute aortic lesions in blunt thoracic trauma patients. Between October 1992 and June 1997, 487 SCT scans of the chest were performed on blunt thoracic trauma patients. To assess aortic injury, the following SCT criteria were considered: hemomediastinum, peri-aortic hematoma, irregular aspect of the aortic wall, aortic pseudodiverticulum, intimal flap and traumatic dissection. Aortic injury was diagnosed on 14 SCT examinations (2.9 %), five of the patients having had an additional digital aortography that confirmed the aortic trauma. Twelve subjects underwent surgical repair of the thoracic aorta, which in all but one case confirmed the aortic injury. Two patients died before surgery from severe brain lesions. The aortic blunt lesions were confirmed at autopsy. According to the follow-up of the other 473 patients, we are aware of no false-negative SCT examination. Our limited series shows a sensitivity of 100 % and specificity of 99.8 % of SCT aortography in the diagnosis of aortic injury. It is concluded that SCT aortagraphy is an accurate diagnostic method for the assessment of aortic injury in blunt thoracic trauma patients. Received 18 July 1997; Revision received 11 September 1997; Accepted 23 October 1997     

双源CT大螺距联合智能调制及迭代重建技术在主动脉夹层成像中的应用

目的 探讨第2代双源CT大螺距扫描联合智能调制技术及迭代重建技术在急诊主动脉夹层成像中的临床应用价值。方法 连续纳入临床怀疑主动脉夹层成像的急诊患者40例,按随机数表法分为对照组和试验组,每组各20例。对照组行常规扫描,试验组行大螺距联合智能调制技术及迭代重建技术扫描。对主动脉平均CT值、平均噪声、信噪比（SNR）、对比噪声比（CNR）、有效剂量,图像整体质量和主动脉根部图像质量进行评价和分析。结果 40例患者均成功完成CT主动脉夹层成像。对照组与试验组的图像整体质量无差异（P>0.05）;但试验组主动脉根部图像质量比对照组好,差异有统计学意义（χ²=22.556,P<0.05）。对照组主动脉平均CT值、平均噪声略高于试验组,但试验组的SNR、CNR高于对照组,差异有统计学意义（t=-21.042、-15.924、8.530、11.495,P<0.05）。对照组有效剂量（10.59±3.89）mSv明显高于试验组的（6.39±0.81）mSv,差异有统计学意义（t=-12.327,P<0.05）。结论 双源CT大螺距扫描联合智能调制技术及迭代重建技术能保证图像整体质量,降低有效剂量,可作为急诊CT主动脉夹层的对照成像方法。     

双源CT对主动脉壁内血肿影像诊断

目的：评价双源CT（DSCT）诊断主动脉壁内血肿的价值。方法：采用西门子DSCT扫描机,连续容积增强扫描,对25例主诉急性胸背痛患者进行DSCT检查并诊断为主动脉壁内血肿。结果：25例按Stanford分型：A型7例,B型18例。DSCT所见主动脉壁内血肿的直接征象：主动脉壁呈新月形或环形增厚≥5mm,无内膜破裂形成的主动脉征象。间接征象：钙化内移7例,穿透性溃疡征12例,主动脉壁粥样硬化改变18例,内膜渗漏5例。并发征象：心包积液5例,胸腔积液14例,主要分支血管受累5例,主动脉夹层3例,主动脉瘤4例。结论：DSCT能为主动脉壁内血肿的诊断和治疗提供重要信息,且便于治疗后随诊观察。     

主动脉夹层的CT及MRI诊断

目的探讨主动脉夹层的CT及MRI表现,评价CT及MRI的诊断价值。方法18例经手术或临床证实的主动脉夹层患者均经CT及MRI检查,CT检查15例,MRI检查14例。结果本组18例中,I型8例,Ⅲ型10例。主动脉夹层位于主动脉轮廓外,CT平扫和增强扫描显示层状密度瘤体,早期强化和显影,MRI显示主动脉夹层壁厚薄不均和信号不均质,均有破裂口。结论CT及MRI对主动脉夹层的诊断有重要价值且操作简单、安全、诊断明确,能帮助和指导手术。     

主动脉夹层螺旋CT血管造影成像的方法与技巧

目的：探讨在主动脉夹层中进行SCTA影像后处理的方法与技巧。方法：选择成功进行SCTA的47例主动脉夹层病例，扫描层厚4－8mm，重建间隔2－3mm，螺距1．25－1．75，数据输入工作站，采用MPR、MIP、SSD及VR等方式进行影像后处理。结果：影像后处理方法有技巧需要在VQ工作站上反复摸索方能熟练掌握；不同的后处理方式得到的图像有不同的显示特点；通过采用不同的显示技术或多种技术相结合；主动脉夹层真假腔、内膜片等得到全面、立体、良好地显示。结论：除了合理地制定扫描计划、选择扫描参数等扫描因素之外，影像后处理方法及技巧的熟练掌握亦是成功获取高质量主动脉夹层图像必不可少的要素。     

Thrombosis of the IVC and azygous continuation of IVC by bronchogenic cancer: CT and MRI appearance

The authors describe the computed tomography (CT) and magnetic resonance imaging (MRI) findings in a patient with thrombosis of the inferior vena cava (IVC) and azygous continuation of the IVC caused by bronchogenic carcinoma. CT has been touted as the modality of choice for mediastinal evaluation. MRI is presently considered to be the initial modality of choice for mediastinal vessel evaluation. MRI is noninvasive, there is no radiation dose to the patient, multiplanar imaging can be done, and there is no need for iodinated contrast material. The satisfactory evaluation of an individual patient may require the use of MRI and CT in a complementary fashion.     

MRI in spontaneous dissection of vertebral and carotid arteries

Summary Fifteen patients were observed between 1987 and 1990: there were six with angiographically confirmed vertebral artery dissection, and 9 with carotid artery dissection. Results showed concordance of MRI and angiographic findings, in all cases but one. The dissected portion consistently showed a semilunar hyperintensity narrowing the residual eccentric signal void of the lumen when the artery was not completely occluded. In one angiographically occluded vessel, MR detected a small signal void within the hyperintensity, indicating that the artery was not completely occluded. The length of the dissected portion was clearly demonstrated by MR. Follow up MR and angiographic studies confirmed the regression of the dissection, and also allowed examination of the cerebral parenchyma.     

多层螺旋CT血管成像技术对主动脉夹层的诊断价值

目的探讨多层螺旋CT血管成像技术对主动脉夹层的诊断价值。方法主动脉夹层(AD)患者17例全部经螺旋CT平扫加增强扫描,并结合二维三维图像重建技术观察。结果本组17例按DeBakey分型,Ⅰ型3例,Ⅱ型1例,Ⅲ型13例。多层螺旋CT血管成像技术的敏感性,特异性较高,能直观、立体地显示真假腔、破裂口、内膜瓣、夹层累及范围和主动脉各分支情况。结论多层螺旋CT血管成像技术可以迅速准确诊断主动脉夹层,是最实用的并值得首选的影像检查方法。     

64-slice spiral CT angiography in the diagnosis of aortic dissection

目的:探讨64层螺旋CT血管成像(CTA)在主动脉夹层(AD)诊断及术前评价中的应用价值.方法:58例连续性AD患者行64层螺旋CTA,对所有数据进行MPR、MIP、VR等重建分析.结果:CTA结果显示依据DeBakey分类法,Ⅰ型夹层14例,Ⅱ型2例,Ⅲ型42例.所有患者均存在明确的撕裂内膜片及真假腔,动脉期真腔平均CT值较假腔高,差异有统计学意义(P=0.000＜0.05).所有患者均明确显示了初始破口的位置,55例显示了一个或多个再破口,3例Ⅲ型患者未显示再破口.39例Ⅲ型患者初始破口位于主动脉弓降部或降胸主动脉近端,其近端瘤颈长度、宽度分别为0.4～10.8 cm(平均3.5 cm)、2.2～3.6 cm(平均2.8 cm),瘤体最大径为3.2～9.2 cm(平均5.4 cm).图像准确显示了所有患者主动脉重要分支受累以及假腔内血栓形成情况.结论:64层螺旋CT血管成像具有无创、快速、准确性高等优点,是主动脉夹层诊断及术前评价的可靠影像学检查方法之一.     

痛风性关节炎的超声研究进展

痛风性关节炎是临床常见疾病,由单钠尿酸盐结晶沉积在软骨、关节和周围软组织引发。超声不仅能用于痛风性关节炎的诊断和疗效评估,还可以引导细针穿刺获得诊断所需的组织样本。介绍痛风性关节炎的实用超声检查方法（六分钟检查法）,以及超声在痛风性关节炎不同时期（无症状高尿酸血症期、急性期、发作间期和慢性期）中的诊断应用。在痛风性关节炎的诊治上,超声比X线、CT和MRI更有效,而且无辐射、检查费用低。