3D DCE MRPA诊断肺栓塞的临床应用研究

目的 :探讨三维动态增强磁共振肺动脉血管成像 (3DDCEMRPA)诊断肺动脉栓塞的价值及限度。方法 :先行MR平扫 ,然后应用快速梯度回波 (FFE)序列对 3 8例怀疑肺栓塞的患者进行 3DDCEMRPA扫描。参数为TR 9ms ,TE 3ms ,矩阵 2 5 6× 12 8,翻转角 2 0° ,对比剂Gd DTPA 0 .2mmol/kg快速注射。结果 :被确诊为肺栓塞的 3 0例患者 ,共发现栓塞 43处 ,其中 3例伴有肺动脉高压。肺栓塞的 3DDCEMRPA的直接征象为肺动脉内充盈缺损 (中心型、部分型、附壁型 )和肺动脉截断 (杵状、平直、锥形及鼠尾状截断 ) ;间接征象为栓塞所属肺野出现梗死灶 ,近心侧肺动脉增粗等肺动脉高压征象及少量胸腔积液。结论 :3DDCEMRPA对中心、叶和段的肺动脉栓塞的诊断价值较大 ,但它对段以下动脉栓子的显示尚有一定限度 ;3DDCEMRPA还是鉴别急性肺动脉高压 (肺栓塞引起 )和慢性肺动脉高压的一个安全有效的手段。     

兔实验性急性肺栓塞双源双能量CT与3.0T MR肺动脉成像联合肺灌注成像的对照研究

目的 评价双源双能量CT与3.0TMR诊断家兔急性肺栓塞的准确性.材料与方法 经股静脉注人明胶海绵栓子制作家兔急性肺动脉栓塞模型,栓塞后2h行双能量CT及MRI,得到CT肺动脉图像(CTPA)、双能量肺灌注图像(DEPI)及MR肺动脉图像(MRPA)和MR肺灌注图像(MRPP).以肺叶为单位,记录栓塞的数目和部位.以病理学为金标准,计算上述方法诊断肺栓塞的敏感性、特异性和一致性.结果 CTPA、DEPI检测肺动脉栓塞的敏感性分别为95.8%、95.8%;特异性分别为94.1%、90.2%;MRPA和MRPP的敏感性和特异性分别为83.3%、90.2%;37.5%、98%.CTPA与DEPI对急性肺动脉栓塞检测的吻合度非常好(Kappa值=0.971,P<0.001),DECT(CTPA和DEPI联合)与MRPA对急性肺动脉栓塞检测的吻合度较好(Kappa值=0.796,P<0.001).对于诊断急性肺动脉栓塞DECT与MRPA的差别无统计学意义(P>0.05);但DEPI诊断肺栓塞的准确性(92%)高于MRPP(78.7%),差别有统计学意义(P<0.001).结论 双源CT诊断家兔实验性急性肺动脉栓塞的敏感性略高于MRPA,但差别无统计学意义;DEPI显示肺栓塞所致的灌注缺损优于MRPP.     

螺旋CT肺血管造影诊断周围性肺栓塞的实验研究

目的 :探讨螺旋CT肺血管造影 (HCTPA)诊断周围性肺栓塞的价值 ,提高对肺栓塞HCTPA表现的认识。材料和方法 :8只犬于DSA下经导管注入直径 2～ 4mm、长 1cm的明胶海绵条后复制为单侧周围性肺栓塞动物模型 ,进行HCTPA检查 ,观察栓塞肺动脉之HCTPA的表现 ,分析HCTPA诊断肺栓塞的敏感性。结果 :栓塞侧肺野共观察到亚段以上肺动脉76支 ,DSA发现 2 6支栓塞肺动脉 ,均位于肺段及以下水平动脉。HCTPA共诊断了 2 0支肺动脉栓塞 ,其中 2支为误诊 ,敏感性为 69.2 % ,特异性为 96%。栓塞肺动脉于HCTPA主要表现为完全或不完全截断。结论 :HCTPA可以对周围性肺栓塞做出可靠的诊断 ,是诊断肺栓塞的理想方法。     

家兔急性肺栓塞的DSA、CTPA及DEPI的对比研究

目的 通过对家兔急性肺栓塞(APE)模型的DSA、CT肺动脉造影(CTPA)及双能量肺灌注成像技术(DE-PI)结果进行对比研究,探讨双源CT肺血管成像技术(CTPA)及DEPI对家兔APE的诊断价值.方法 10只实验用兔,X线透视下将4F导管经由右心室插入双侧肺动脉,并注入大小不等的明胶海绵,建立家兔APE模型,然后行DSA及双源CT DEPI,处死家兔进行病理解剖学检查.(1)分别计算DSA、CTPA、DEPI诊断家兔APE的敏感性及特异性,利用Kappa分析比较3种方法(DSA、CTPA、DEPI)与病理解剖结果的一致性;(2)利用配对t检验计算并比较家兔栓塞前后的双室短轴最大径比(RV/LV)值.结果 (1)与病理解剖结果相比,DSA、CTPA及DEPI诊断APE的敏感性和特异性分别为90.5％和100％、71.4％和100％、85.7％和92.9％,Kappa值分别为0.884、0.667、0.767,DEPI及DSA的一致性较好,CTPA的一致性一般.DEPI上,栓塞区表现为蓝黑色的灌注减低区,非栓塞区表现为黄红色的正常灌注区.(2)栓塞前后家兔的RV/LV差异有统计学意义(P =0.02 ＜0.05),栓塞后家兔的RV/LV值明显高于栓塞前.结论 双源CT的CTPA能较好地显示肺解剖信息,DEPI能较好地评价肺功能信息,对APE有着重要的诊断价值.     

3D-CE-MRPA诊断周围性肺栓塞的研究

目的：探讨三维增强磁共振肺血管造影(3D-CE—MRPA)对周围性肺栓塞的诊断价值。方法：8只犬于DSA下经导管将直径2—4mm、长1cm左右的明胶海绵条注入单侧肺动脉后复制为周围性肺栓塞动物模型，然后进行3D-CE—MRPA检查，观察栓塞肺动脉的CEMRPA显示情况及表现形式，分析CEMRPA诊断肺栓塞的敏感性。结果：在DSA显示的26支肺段及其以下水平栓塞肺动脉中，CEMRPA显示了21支，敏感性为80．77％，特异性为100％。栓塞肺动脉主要表现为完全或不完全截断，远侧肺野可见低灌注区存在。多平面重建协助诊断了4支原始图像上显示不清的栓塞肺动脉。结论：3D-CE—MRPA对周围性肺栓塞有较高的诊断敏感性，是诊断周围性肺栓塞的理想方法。多平面重建有助于诊断原始图像上显示不清的栓塞肺动脉。     

能谱成像在肺栓塞诊断中的临床应用

目的探讨宝石CT能谱成像碘基图及最佳单能量成像在肺栓塞诊断中的价值。方法对28例肺栓塞患者行宝石CT能谱增强扫描,以70Kev单能量图为标准对照最佳单能量图像CTPA观察肺动脉内有无栓子,并记录栓子发生的部位及数量;定量测定肺组织碘基图中碘含量正常区与异常区的碘含量值并记录碘含量异常区的部位及数量,通过配对t检验分别观察两组结果间的差异;与70Kev CTPA单能量图的诊断一致性采用Kappa检验,同时计算出最佳单能量成像、肺组织碘基图诊断肺栓塞的敏感性、特异性、阳性预测值及阴性预测值。结果 28例患者利用70KevCTPA图像共发现肺栓塞108处,CTPA最佳单能量图共显示128处肺栓塞,肺组织碘基图共检出133处,碘含量异常区均值(0. 12±2. 11) 100μg/cm~3,碘含量正常区均值(18. 56±6. 37) 100μg/cm~3,二者的差异有统计学意义(t=21. 26,P 0. 05)。最佳单能量成像、肺碘基图与70Kev CTPA对肺栓塞的诊断经一致性Kappa检验K值分别为(K=0. 924、K=0. 935,P 0. 001),二者联合对照70Kev CTPA图像诊断肺栓塞具有良好的一致性。肺碘基图联合最佳单能量图诊断肺动脉主干栓塞的敏感性、特异性、阳性预测值及阴性预测值均为100%;诊断肺叶动脉栓塞的敏感性为95. 83%,特异性为100%,阳性预测值为100%,阴性预测值为99. 85%;诊断肺段动脉栓塞的敏感性为86. 76%,特异性为99. 19%,阳性预测值为95. 16%,阴性预测值为97. 62%;诊断肺亚段动脉栓塞的敏感性为80. 77%,特异性为99. 88%,阳性预测值为95. 45%,阴性预测值为99. 42%。结论宝石CT最佳单能量图像可以提高肺段以下动脉栓塞的显示率,能谱肺碘基图反映了肺组织血流灌注情况,能够显示肺栓塞时肺血管功能的改变,二者结合对肺栓塞的早期诊断、病情评估及疗效评价提供重要依据,具有重要的临床应用价值。     

16层螺旋CT肺血管造影在肺动脉栓塞诊断中的应用

目的　研究 16层螺旋CT肺血管造影在肺动脉栓塞诊断中的应用价值。方法　使用 16层螺旋CT扫描机 (SiemensSensation 16 )对临床拟诊肺栓塞的 4 9例患者进行前瞻性研究。采用层厚 3mm行胸部增强扫描。利用原始数据行层厚 1mm的轴面及多平面重建 (MPR)。比较层厚 3mm、1mm的轴面图像及MPR图像。结果　CT诊断肺栓塞 4 2例。病变共累及肺动脉 35 2支。对于主肺动脉及肺叶动脉栓塞 ,三种图像检出结果一致。但对于肺段及亚段动脉栓塞 ,层厚 1mm较 3mm显示率高 ,差异有显著意义 (P <0 0 1) ,1mm的MPR较轴面图像显示率高 ,但差异无显著性意义 (P >0 0 5 )。结论　 16层螺旋CT肺血管造影无创、快速、敏感性高 ,应当作为肺栓塞的首选检查方法。     

肺栓塞MR增强肺灌注成像与核素肺灌注显像对比实验研究

目的:比较MR及SPECT核素肺灌注显像诊断肺栓塞的价值。方法:24只大白兔建立肺栓塞模型,栓塞后6h采用3D-FLASH序列,从耳缘静脉注入Gd-DTPA行肺灌注扫描,应用Evaluation自动生成肺灌注曲线,在冠状位原始图像上两侧对称性选取正常与病变区肺实质的ROI测量时间-信号强度曲线。从耳缘静脉注入99Tcm-MAA111-148MBq0·3ml8体位显像。病理学检查:分别于栓塞后分批处死实验动物,光学显微镜下观察栓塞肺组织及正常肺组织的表现。统计学采用t检验和χ2检验。结果:成功建立20只兔肺栓塞模型,栓塞后6hMR增强肺灌注成像正常和栓塞区肺实质增强率分别为317·5%和45·1%;正常肺组织灌注曲线峰值明显,栓塞区灌注曲线低平或峰值延迟(t=11·52,P<0·01)。MR增强肺灌注成像对肺栓塞模型检测的敏感性为95%,特异性为85%;SPECT肺灌注显像敏感性100%,特异性65%,统计学分析二者检查结果差异不具有统计学意义(χ2=2·06,P>0·05)。病理显示:梗死区可见大量的纤维素渗出,肺间质增厚,动脉腔内可见红细胞和血栓形成,其周围白细胞浸润伴肺淤血,部分可见点状出血及肺淤血。结论:Gd-DTPAMR增强肺灌注成像诊断肺栓塞是可行的;MR诊断肺栓塞与SPECT具有较好的一致性。     

宝石CT能谱成像技术在肺栓塞诊断中的价值

目的探讨宝石CT能谱成像技术在肺栓塞诊断中的价值。方法对22例肺栓塞患者行宝石CT能谱增强扫描,通过数据处理同时获得CT肺动脉造影(CTPA)及肺组织碘基图。在CTPA图上观察肺动脉内有无栓子,并记录栓子发生的部位及数量;定量测定肺组织碘基图中碘含量正常区与异常区的碘含量值,并记录碘含量异常区的部位及数量,通过配对t检验观察两组结果间的差异;以CTPA诊断结果为参照,肺组织碘基图与CTPA的诊断一致性采用Kappa检验,同时计算出肺组织碘基图诊断肺栓塞的敏感性、特异性、阳性预测值及阴性预测值。结果22例患者CTPA共诊断124处肺栓塞,其中左右肺动脉6处,肺叶动脉24处,肺段动脉68处,肺亚段动脉26处。肺组织碘基图共检出113处肺组织碘含量降低,碘含量异常区均值0.12±2.11(100μg/cm3),碘含量正常区均值18.56±6.37(100μg/cm3),二者的差异有统计学意义(t=22.43,P<0.05)。以CTPA为参照,肺碘基图诊断了左右肺动脉水平6处,肺叶动脉水平23处,肺段动脉水平59处,肺亚段动脉水平21处肺栓塞;另有4处肺碘基图异常而CTPA诊断为阴性。肺碘基图与CTPA对肺栓塞的诊断经一致性Kappa检验(K=0.913,P<0.001),二者具有良好的一致性。肺碘基图诊断左右肺动脉栓塞的敏感性、特异性、阳性预测值及阴性预测值均为100%;诊断肺叶动脉栓塞的敏感性为95.83%,特异性为100%,阳性预测值为100%,阴性预测值为98.85%;诊断肺段动脉栓塞的敏感性为86.76%,特异性为99.19%,阳性预测值为95.16%,阴性预测值为97.62%;诊断肺亚段动脉栓塞的敏感性为80.77%,特异性为99.88%,阳性预测值为95.45%,阴性预测值为99.42%。结论宝石CT能谱肺碘基图反映了肺组织血流灌注情况,能够显示肺栓塞时肺血管功能的改变,对肺栓塞的早期诊断、病情评估及疗效评价提供重要依据,具有重要的临床应用价值     

多层螺旋CT肺血管造影在肺动脉栓塞中的应用

目的：探讨多层螺旋CT肺血管造影在肺动脉栓塞诊断中的应用。方法：使用6层螺旋CT对39位肺动脉栓塞患者进行血管成像检查。应用准直1．0mm,螺距1．25进行扫描,将得到的原始数据行层厚1．25mm、3．0mm轴面重建,MIP2mm、5mm多视角多平面重组及MRP重组。分析不同后处理技术的检出栓塞动脉支数进行比较。结果：39例肺动脉栓塞患者,共累及肺动脉血管326支,以上5种重建方法对肺动脉主干及叶动脉的栓塞,显示检出结果一致。对段及亚段动脉的栓塞MPR优于其它后处理方法（P〈0．05）。结论：多层螺旋CT血管造影是肺栓塞安全、敏感性且特异性高的无创性诊断方法,其图像后处理技术更为直观、全面的显示栓子的形态、部位、范围。     

慢性阻塞性肺部疾病的肺功能与CT肺功能研究

慢性阻塞性肺疾病(chronic obstructive pulmonarydisease,COPD)是指具有气流阻塞的慢性支气管炎和肺气肿。没有气流阻塞的慢性支气管炎和肺气肿不属于COPD。慢性阻塞性肺疾病以不可逆性气流受限为特征,继发于气道炎症和肺实质的肺气肿性改变。气道高反应性也是COPD的常见征象[1]。因此,对怀疑有COPD的患者,临床诊断常用肺功能试验(pulmonaryfunction test,PFT)测定第1秒用力肺活量实测值与预测值百分比(forced expiratory volume at1second,FEV1%)、第1秒用力肺活量与用力肺活量(forced vi-tal volume,FVC)的比值(FEV1/FVC)等…     

Pulmonary arteriography

Developments in catheter design, contrast media, and radiologic equipment have simplified the performance of pulmonary arteriography. With proper precautions the procedure is acceptably safe even in critically ill patients. This procedure should be part of the repertoire of any active and properly equipped angiographic laboratory.     

Pulmonary circulation

Evaluation of the pulmonary vasculature is mainly indicated in patients with suspected pulmonary thromboembolism. The routine procedure so far is ventilation-perfusion scintigraphy alone or in combination with diagnostic assessment of the legs to rule out deep venous thrombosis. The results are still not reliable for the majority of patients. In the case of equivocal diagnosis, invasive conventional angiography is considered the gold standard. With steady improvements in tomographic imaging techniques, such as computed tomography (CT) or magnetic resonance imaging (MRI), non-invasive alternatives to the routine diagnostic work-up are given. Helical CT and CTA techniques are already in clinical use and estimated to sufficiently serve the demands for detection/exclusion of pulmonary thromboembolism. The disadvantages mainly concern peripheral disease and reconstruction artifacts. MRI and MR angiography have been implemented in the diagnosis of pulmonary vascular disease since the introduction of contrast-enhanced MRA. In breath-hold techniques, the entire lung vascularization can be delineated and thromboemboli can be detected. The clinical experience in this field is limited, but MRI has the potential to demonstrate its superiority over CT due to its improved delineation of the vascular periphery and the more comprehensive three-dimensional reconstruction. Received: 20 January 1998; Accepted: 10 February 1998     

Balloon Pulmonary Angioplasty for Chronic Thromboembolic Pulmonary Hypertension

CardioVascular and Interventional Radiology - Chronic thromboembolic pulmonary hypertension (CTEPH) is a potentially lethal outcome of pulmonary embolism. Balloon pulmonary angioplasty (BPA) is...     

Pulmonary embolism

Pulmonary embolism is a common medical problem whose incidence is likely to increase in our aging population. Although it is life-threatening, effective therapy exists. The treatment is not, however, without significant complications. Thus, accurate diagnosis is important. Unfortunately, the clinical manifestations of pulmonary embolism are nonspecific. Furthermore, in many patients the symptoms of an acute embolism are superimposed on underlying chronic heart or lung disease. Thus, a high index of suspicion is needed to identify pulmonary emboli. Laboratory parameters, including arterial oxygen tensions and electrocardiography, are as nonspecific as the clinical signs. They may be more useful in excluding another process than in diagnosing pulmonary embolism. The first radiologic examination is the chest radiograph, but the clinical symptoms are frequently out of proportion to the findings on the chest films. Classic manifestations of pulmonary embolism on the chest radiograph include a wedge-shaped peripheral opacity and a segmental or lobar diminution in vascularity with prominent central arteries. However, these findings are not commonly seen and, even when present, are not specific. Even less specific findings include cardiomegaly, pulmonary infiltrate, elevation of a hemidiaphragm, and pleural effusion. Many patients with pulmonary embolism may have a normal chest radiograph. The chest radiograph is essential, however, for two purposes. First, it may identify another cause of the patient's symptoms, such as a rib fracture, dissecting aortic aneurysm, or pneumothorax. Second, a chest radiograph is essential to interpretation of the radionuclide V/Q scan. The perfusion scan accurately reflects the perfusion of the lung. However, a perfusion defect may result from a variety of etiologies. Any process such as vascular stenosis or compression by tumor may restrict blood flow. In addition, areas of the lung that are not well ventilated will be poorly perfused. Thus, a ventilation scan and a chest radiograph are essential to optimal interpretation of the perfusion scan. Ventilation/perfusion scans are interpreted as degrees of probability of pulmonary embolism. Emboli are not present in patients with a normal V/Q scan. An embolus is unlikely (10%-15%) among patients with a low-probability V/Q scan. However, small emboli that are nonocclusive may be present, and pulmonary arteriography may be used to further evaluate patients with a high clinical suspicion of pulmonary embolus.(ABSTRACT TRUNCATED AT 400 WORDS)