核素肺显像RM—PIOPED与PISA-PED评价标准用于急性肺栓塞诊断的比较研究

目的比较放射性核素肺显像的2种评价标准和临床肺栓塞危险度分层对诊断急性肺动脉血栓栓塞症（PTE）的一致性和效能。方法分析2005年10月至2007年7月共104例连续性临床疑诊急性PTE患者的放射性核素肺显像和临床情况,分别采用麦克马斯特（McMaster）临床危险度分层：核素肺显像修订版肺栓塞诊断前瞻陛研究（RM—PIOPED）评价标准、急性肺栓塞诊断前瞻性调查研究（PISA-PED）评价标准进行诊断。以汇总肺动脉增强CT扫描（CTPA）、肺动脉造影（PAA）、各实验室检查、临床病史及临床治疗反应讨论得出的最终诊断作为“标准诊断”,然后比较2种显像评价标准及McMaster临床危险度分层相互之间的一致性和诊断效能。采用Kappa分析比较2种评价方法之间的一致性;配对,检验比较2种评价方法之间的差异有无统计学意义。结果2种显像评价标准及McMaster临床危险度分层之间：PISA—PED评价标准与RM—PIOPED评价标准的一致性好（Kappa值为0．92,P〈0．05）;McMaster临床危险度分层与RM—PIOPED评价标准及PISA—PED评价标准的一致性差（Kappa值均为0．35,P均〉0．05）。104例患者中55例被诊断为急性PTE,占52．9％。McMaster临床危险度分层、RM—PIOPED评价标准及PISA—PED评价标准的灵敏度分别为69．1％（38／55）、90．9％（50／55）、92．7％（51／55）;特异性分别为73．5％（36／49）、73．5％（36／49）、75．5％（37／49）;准确性分别为71．2％（74／104）、82．7％（86／104）、84．6％（88／104）。对于该2种评价标准及McMaster临床危险度分层,特异性两两之间差异均无统计学意义（χ^2值分别为0．00,0．05,0．05,P均〉0．05）;RM-PIOPED评价标准的灵敏度与PISA—PED评价标准之间差异亦无统计学意义（χ^2=0．12,P〉0．05）;但McMaster临床危险度分层的灵敏度与2种评价标准之间?     

肺通气/灌注显像与多层螺旋CT诊断慢性血栓栓塞性肺动脉高压的对比研究

目的 对比肺通气/灌注(V/Q)显像与多层螺旋CT肺血管造影(CTPA)诊断慢性血栓栓塞性肺动脉高压(CTEPH)的准确性,评价2种影像学方法的诊断符合程度.方法 49例肺动脉高压患者,经超声心动图排除瓣膜性心脏病和先天性心脏病,既往无急性肺栓塞病史.所有患者先后行肺V/Q显像和CTPA检查,并以肺动脉造影为"金标准"进行对比评价.对V/Q显像和CTPA检查结果比较进行χ2检验,采用SPSS 12.0统计软件.结果 肺V/Q显像对CTEPH的诊断灵敏度、特异性和准确性分别为100.0%(17/17),71.9%(23/32)和81.6%(40/49),CTPA分别为94.1%(16/17),81.2%(26/32)和85.7%(42/49).肺V/Q显像与CTPA的诊断符合率为75.5%(37/49),Kappa值为0.513,2种影像学方法的诊断结果差异无统计学意义(χ2=0.75,P>0.05).结论 肺V/Q显像和CTPA均是诊断CTEPH有效的无创性影像学方法,两者结合应用有助于更好地诊断CTEPH.     

肺通气/灌注显像与多层螺旋CT肺动脉造影诊断慢性血栓栓塞性肺动脉高压的前瞻性对比研究

目的 比较肺V/Q显像与多层螺旋CT肺动脉造影(CTPA)对慢性血栓栓塞性PAH(CTEPH)的诊断效能.方法 2006年1月至2010年12月间疑诊为CTEPH的PAH患者133例[男54例、女79例,15～78(43.1±14.9)岁]均在7d内接受肺V/Q显像、CTPA和肺动脉造影检查.以肺动脉造影为“金标准”,评价其他2种方法诊断准确性.V/Q显像结果包括CTEPH高度可能性、中度可能性和低度可能性;CTPA结果包括CTEPH阳性、阴性及不能诊断.应用Kappa检验分析这2种方法诊断结果的一致性.结果 其中51例患者被最终确诊为CTEPH(38.3％);其余82例中,60例诊断为IPAH,19例诊断为肺血管炎,3例为房间隔缺损.以CTEPH高度可能性作为阳性标准时,V/Q显像的诊断灵敏度为96.1％(49/51),特异性为75.6％(62/82),准确性为83.5％(111/133);以CTEPH高度和中度可能性均作为阳性标准时,V/Q显像的诊断灵敏度为100％(51/51),特异性为73.2％(60/82),准确性为83.5％(111/133).CTPA的诊断灵敏度为92.2％(47/51),特异性为92.7％(76/82),准确性为92.5％(123/133).V/Q显像以CTEPH高度可能性作为阳性标准时,V/Q显像与CTPA的诊断符合率为80.5％(107/133),Kappa=0.612,P＜0.001.结论 对于CTEPH的诊断,V/Q显像灵敏度较高;而CTPA则特异性较高,且对肺血管炎等其他PAH疾病鉴别力较好.两者结合可能有助于提高对CTEPH诊断的准确性.     

放射性核素肺显像诊断肺栓塞研究进展

PE是常见的危及患者生命的急重症,早期准确诊断至关重要.放射性核素肺显像是诊断PE的无创影像学方法.近年来,肺V/Q显像取得了重要研究进展.(1)20世纪90年代初由肺栓塞诊断前瞻性研究(PIOPED)制定了目前广泛应用的V/Q显像PIOPED Ⅰ诊断标准.在该研究中,PE中度可能性和低度可能性患者(即非诊断性结果)的比例很高.因此,PIOPED Ⅰ标准存在缺陷,众多学者对此进行了研究,并制定了多个新的诊断标准,如PIOPEDⅡ、PISAPED和EANM标准；(2) SPECT V/Q显像为三维成像,具有空间分辨率高和受组织重叠影响少的优势,能发现亚段水平和肺底部位的病灶,其诊断准确性高于V/Q平面显像和多层螺旋CT；(3)近年出现的SPECT/CT一次检查可同时获取SPECT图像和CT图像,两者融合可同时提供功能信息和解剖信息,优势互补,提高了PE诊断的准确性.     

核素肺灌注显像结合PISA-PED评价标准与CT肺动脉造影诊断肺栓塞的对比研究

目的 比较核素肺灌注显像结合PE诊断前瞻性研究(PISA-PED)评价标准与CT肺动脉造影(CTPA)诊断PE的效能.方法 前瞻性纳入104例连续性疑似PE患者,其中男54例,女50例,年龄(50±15)岁.排除标准为:孕妇、肾功能衰竭患者、已接受溶栓或抗凝治疗患者或有造影剂过敏史患者.所有患者均行核素肺灌注显像、CTPA及胸部X线检查.采用PISA-PED评价标准判读核素肺灌注显像图.最终诊断采用临床综合诊断.应用Kappa检验分析肺灌注显像与CTPA结果的一致性,应用非参数检验或x2检验分析2种诊断方法结果间的差异性.结果 104例患者中55例被最终诊断为PE.在排除3例(2.9％)CTPA“不能诊断”者后,肺灌注显像的灵敏度、特异性、阳性预测值及阴性预测值分别为92.6％ (50/54)、83.0％( 39/47)、86.2％( 50/58)和90.7％ (39/43);CTPA的灵敏度、特异性、阳性预测值及阴性预测值分别为96.3％ (52/54)、93.6％( 44/47)、94.5％( 52/55)和95.7％ (44/46).2种显像方法的诊断符合率为89.1％(90/101),Kappa =0.78,P＜0.05.在肺段水平,共分析了1664个肺段,肺灌注显像与CTPA的诊断符合率为79.7％ (1327/1664),Kappa=0.58,P＜0.05.结论 核素肺灌注显像结合PISA-PED评价标准与CTPA诊断PE的效能相近,两者均有较好的诊断效能.2种显像方法在肺段水平为中度符合.     

肺通气/灌注平面显像与肺灌注SPECT/CT对肺栓塞诊断价值的对比性研究

目的：探讨传统的肺通气/灌注（V/Q）平面显像、肺灌注断层显像与低剂量平扫CT相结合（肺Q SPECT/CT）对肺栓塞的诊断价值。方法收集69例临床可疑肺栓塞患者,在对其行肺V/Q平面显像的同时,进行了肺Q SPECT/CT显像。以临床最终确诊结果为金标准,对两种方法的诊断结果进行对比分析。结果69例临床可疑肺栓塞患者,最终确诊43例,排除26例。肺Q SPECT/CT对肺栓塞诊断的灵敏度、准确率、阴性预测值及与临床最终确诊结果的Kappa值均较肺V/Q平面显像高;肺Q SPECT/CT对合并有慢性阻塞性肺疾病（COPD）的病例诊断的特异度较肺V/Q平面显像低。排除COPD病例的影响后,肺Q SPECT/CT的特异度明显提高,且高于肺V/Q平面显像的特异度。两种方法检出肺栓塞的一致性为85%（34/40）,且两种方法检出率之间的差异有统计学意义（χ2=8.10,P<0.05）。结论肺Q SPECT/CT明显提高了对不伴有COPD的肺栓塞患者的诊断价值,用肺Q SPECT/CT取代肺V/Q平面显像值得商榷。     

肺通气/灌注平面与断层显像诊断肺栓塞效能的多中心对比研究

目的 运用ROC分析方法对比一日法肺V/Q断层显像与传统平面显像在PE诊断中的效能.方法 对2010年9月至2011年10月北京市6家三级甲等医疗机构收治的确诊或疑诊急性或亚急性PE,且Wells评分≥2分或血浆D-二聚体＞500 μg/L的患者272例,均行一日法肺V/Q平面及断层显像.肺V/Q平面显像结果参照PE诊断前瞻性研究Ⅱ(PIOPEDⅡ)标准,分为PE高度可能性(确诊PE)、中度或低度可能性(不能确定)、极低度可能性或肺灌注正常(排除PE),灌注显像结果也分为确诊PE、不能确定(非特定疾病典型表现的多发V/Q异常)、排除PE.全部患者显像后随访6个月.最终以综合分析各影像学检查、实验室检查、临床可能性评估和6个月的随访结果来判定为确诊或排除PE.应用Kappa检验分析2种显像方法结果的一致性,应用x2检验对肺V/Q断层显像和平面显像在PE诊断上的常用评价指标进行比较;运用ROC曲线分析,计算并比较(Z检验)各AUC及其95％ CI;比较2种方法不确定诊断率的差异.结果 肺V/Q断层显像在诊断PE中的不确定诊断率(1.8％,5/272)仅为平面显像(9.2％,25/272)的1/5.以最终诊断为标准,肺V/Q断层和平面显像对272例PE的诊断指标分别为:Se 83.6％ (117/140)与78.3％(101/129,x2=1.217,P＞0.05),Sp 89.8％ (114/127)与94.9％(112/118,x2=2.269,P＞0.05),PPV 90.0％(117/130)与94.4％ (101/107),NPV 83.2％ (114/137)与80.0％(112/140),Ac 86.5％(231/267)与86.2％ (213/247).2种显像方法诊断PE的符合率为84.9％(231/272,Kappa=0.727,P＜0.05),一致性较好.运用ROC分析2种显像方法的AUC及95％ CI,断层显像分别为0.891 (0.848 ～0.933),平面显像分别为0.865(0.819～0.911)(Z=2.65和2.03,均P＜0.05),提示肺V/Q断层显像对PE具有更高的诊断效能.结论 一日法肺V/Q断层显像较平面显像显著降低PE不确定诊断的比例,明显提高V/Q显像的临床实用性;肺V/Q断层显像在诊断PE的总体效能上高于平面显像.     

64层CT血管成像与肺通气灌注显像诊断肺栓塞的对比研究

目的:通过比较两种无创影像检查为临床诊断肺栓塞提供有指导意义检查方法。方法:64层螺旋CT肺动脉成像和肺通气/灌注显像图像依据相同的诊断标准进行独立的分析。V/Q显像和多层螺旋CT肺动脉成像两种检查方法的判定结果进行相关分析,两者准确性、符合性及不确定性诊断比率的差异采用2检验进行比较。结果:180例患者中CTPA和V/Q显像诊断PE的敏感性、特异性、符合率分别为90.5%对83.8%,91.5%对85.0%,91.1%对84.4%。CTPA和V/Q显像诊断PE的κ值分别为0.680,0.648。结论:疑诊肺栓塞病例中两者皆可作为确诊及排除疑诊肺栓塞病例的检查方法。     

放射性核素肺显像与螺旋CT诊断急性肺栓塞的对比研究

目的 比较肺通气／灌注（V／Q）显像与多层螺旋CT肺动脉造影（CTPA）在诊断急性肺动脉血栓栓塞症（PTE）方面的临床价值。方法 前瞻性分析2005年10月～2006年5月共51例临床疑诊急性PTE患者的肺灌注显像，其中18例行肺通气显像，并与CTPA对比。以汇总所有临床资料、各实验室检查及影像学检查后讨论得出的最终诊断作为“标准”。结果 最终24位患者被诊断为PTE占47．1％（24／51例），V／Q显像与CTPA的灵敏度分别为95．8％（23／24例）和95．8％（23／24例），特异性分别为88．9％（24／27例）和92．6％（25／27例），准确性分别为92．2％（47／51例）和94．1％（48／51例）。在定性诊断方面，2种影像学检查结果差异无统计学意义（χ^2=0．14，P=0．71），两者定性诊断符合率为86．3％（44／51例），Kappa值为0．73。24例PTE患者中，CTPA显示为“完全阻塞”的肺动脉血管所对应的44个肺段中，肺灌注显像显示为“放射性稀疏、缺损”的肺段数为32个（72．7％）；CTPA显示为“部分充盈缺损”的肺动脉血管所对应的266个肺段中，肺灌注显像显示为“放射性稀疏、缺损”的肺段数为155个（58．3％），显示为“亚肺段放射性稀疏、缺损”的肺段数为9个（3．4％）。结论 V／Q显像与CTPA在PTE定性诊断方面符合率高，一致性好，但在定位方面存在差异；两者为互补关系。     

肺通气/灌注显像在慢性血栓栓塞性肺动脉高压诊断中的临床价值

目的 探讨肺通气/灌注(V/Q)显像在慢性血栓栓塞性肺动脉高压(CTEPH)诊断中的临床价值.方法 回顾性分析临床怀疑CTEPH的76例患者(男46例,女30例,年龄27～84岁)的肺V/Q断层显像结果,与CT肺动脉造影(CTPA)检查结果进行比较.分别计算核素显像与CTPA诊断CTEPH的灵敏度、特异性、准确性、阳性预测值和阴性预测值,并应用SPSS 11.5软件行x2检验,对2种方法诊断效能进行比较.同时对CTEPH患者V/Q显像受累肺段的分布进行分析.结果 临床最终确诊CTEPH 47例(肺动脉造影或病史结合影像学检查结果确诊),非CTEPH 29例.V/Q显像对CTEPH的诊断灵敏度、特异性、准确性、阳性预测值和阴性预测值分别为97.9％(46/47)、86.2％ (25/29)、93.4％(71/76)、92.0％(46/50)和96.2％ (25/26),CTPA的检查对应结果分别为78.7％ (37/47)、93.1％ (27/29)、84.2％ (64/76)、94.9％ (37/39)和73.0％(27/37),V/Q显像的灵敏度(x2=5.818,P=0.012)和阴性预测值(x2=5.693,P=0.017)均高于CTPA.V/Q显像可以对CTEPH和特发性PAH及遗传性PAH进行鉴别诊断:CTEPH患者灌注显像呈肺叶、肺段分布的稀疏缺损区,而通气显像基本正常,特发性及遗传性PAH灌注显像则表现为不呈肺段分布的多发、散在的“斑片状”稀疏缺损区或血流灌注基本正常.在47例CTEPH患者的940个肺段中,肺灌注断层显像共检出585个(62.2％)受累肺段,平均每例患者有12.4个肺段受累,右肺受累比例明显高于左肺[36.2％ (340/940)与26.1％ (245/940);x2=40.85,P＜0.01].结论 V/Q显像在CTEPH的诊断和鉴别诊断中具有较高的临床应用价值.V/Q显像正常可排除CTEPH的诊断;而在临床高度怀疑CTEPH、CTPA与肺动脉造影检查均为阴性时,V/Q显像对CTEPH的诊断具有重要意义.     

Can CT pulmonary angiography replace ventilation-perfusion scans as a first line investigation for pulmonary emboli?

A prospective study was performed to determine efficacy of diagnosis of pulmonary emboli by computed tomographic pulmonary angiography (CTPA) in patients who underwent both CTPA and ventilation-perfusion (V/Q) scanning. The results were compared with the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study in which conventional pulmonary angiography had been performed instead of CTPA. Forty-two of 161 (26%) patients had a positive CTPA compared with a 27% prevalence in the PIOPED population. Fourteen of 16 patients (87.5%) with high-probability V/Q scans also had a positive CTPA compared with 87% in PIOPED. Twelve of 40 patients (30%) with intermediate probability V/Q scans also had a positive CTPA compared with 34.7% in PIOPED, while 12 of 80 patients (15%) who had low-probability V/Q scans had positive CTPA compared with 14.5% in PIOPED. Four of 25 patients (16%) with normal V/Q scans had positive CTPA compared with 0% in PIOPED. While the present study size was relatively small, the results compared favourably with PIOPED, suggesting that equivalent prevalence of clot was being detected using CTPA. This result, together with the cost considerations, has led us to replace V/Q scanning with CTPA for investigation of the majority of cases of suspected, acute pulmonary emboli.     

V/Q SPECT and computed tomographic pulmonary angiography

Planar ventilation and perfusion (V/Q) scintigraphy has been largely displaced by computed tomography pulmonary angiography (CTPA) in recent years for the diagnosis of pulmonary embolism (PE). This change can be attributed to multiple studies that demonstrate CTPA has a reasonable sensitivity and good prognostic value in negative cases, associated with the ability to deliver few indeterminate results and provide an alternate diagnosis in a significant number of patients. However, the technique has significant limitations. The Prospective Investigation of Pulmonary Embolism Diagnosis II (PIOPED II) study has shown a sensitivity of 83%, which is not optimal. However, CT technology has greatly progressed since this time, and therefore it is likely that this number has improved. The PIOPED II study has also shown that there may be a problem in positive or negative predictive value when the imaging results are discordant with the clinical probability. Additional concerns include allergies, contrast nephropathy associated with the use of intravenous contrast in patients with impaired creatinine clearance, suboptimal results in pregnant women, and high radiation exposure. In recent years, V/Q single-photon emission computed tomography has emerged as a mature technique for the diagnosis of PE and has been shown to be clearly superior to planar V/Q. The technique has excellent sensitivity for PE and is not associated with most of the limitations of CTPA, although it has its own set of limitations in patients with very severe chronic obstructive pulmonary disease or with a severely abnormal chest x-ray. V/Q single-photon emission computed tomography can be used as the initial modality for PE diagnosis in a wide variety of situations although CTPA remains invaluable in specific scenarios.     

同机低剂量CT在肺通气／灌注SPECT显像诊断肺栓塞中的价值

目的评价同机低剂量cT对放射性核素肺V／QSPECT显像诊断PE的辅助价值。方法回顾性分析102例疑似PE患者的V／QSPECT显像和同机低剂量cT资料。采集患者的相关临床资料和检查结果,并随访3个月或以上。依据欧洲心脏病学会2008年指南所述标准作临床最终诊断,并以临床最终诊断作为“金标准”,评价V／QSPECT显像及其结合同机低剂量CT诊断PE的效能。分析同机低剂量cT在V／QSPECT显像所示异常部位的表现及其对PE鉴别诊断的价值。采用SPSS13．0软件进行统计分析,以四格表,检验比较V／QSPECT显像与其结合同机cT诊断效能间差异。结果在纳入研究的102例患者中,29例（28．43％）被最终诊断为PE。V／QSPECT显像的灵敏度、特异性及准确性分别为93．10％（27／29）、90．41％（66／73）及91．18％（93／102）,无“不确定”结果。V／QSPECT显像结合同机低剂量CT后,其灵敏度、特异性及准确性分别为93．10％（27／29）、95．89％（70／73）及95．10％（97／102）,无“不确定”结果,与单独的V／QSPECT显像相比,灵敏度无变化,特异性和准确性提高,但差异无统计学意义（,值分别为1．72和1．23,P均〉0．05）。结论V／QSPECT显像结合同机低剂量CT对PE的诊断效能较高。同机低剂量CT有助于PE的鉴别诊断。     

Comparison of observer variability and accuracy of different criteria for lung scan interpretation.

Different criteria have been advocated for the interpretation of ventilation/perfusion (V/Q) lung scans in patients with suspected pulmonary embolism (PE). Besides these predefined criteria, many physicians use an integration of the different sets of criteria and their own experience-the so-called Gestalt interpretation. The purpose of this study was to evaluate interobserver variability and accuracy of 3 sets of criteria: the Hull and PIOPED (Prospective Investigation of Pulmonary Embolism Diagnosis) criteria and the Gestalt interpretation. METHODS: Two experienced observers interpreted V/Q scans of all 328 patients according to the 3 different schemes. The diagnostic classification obtained for the different sets of criteria was analyzed against the presence or absence of PE. RESULTS: The interobserver variabilities as assessed by the kappa statistics of the PIOPED and Hull criteria and for the Gestalt interpretation were 0.70 (95% confidence interval [CI], 0.64-0.76), 0.79 (95% CI, 0.73-0.85), and 0.65 (95% CI, 0.58-0.72), respectively. The differences in kappa values between the Hull and PIOPED criteria and between the Hull criteria and Gestalt interpretation were statistically significant (P < 0.05 and P < 0.001, respectively). For 16 patients (14 without PE) with a normal lung scan result according to the Hull criteria, the result according to the PIOPED criteria was low probability. For 21 patients (12 with PE), the scans were intermediate probability according to the PIOPED criteria, whereas the result with the Hull criteria was high probability. Analysis of receiver-operating-characteristic curves yielded a comparable area under the curve for all sets of criteria (0.87-0.90). CONCLUSION: The Hull, PIOPED, and Gestalt interpretation of V/Q lung scans all have a good accuracy and interobserver variability. However, the reproducibility of the Hull criteria is superior in comparison with that of the other sets of criteria.     

Distribution of ventilation/perfusion ratios in pulmonary embolism: an adjunct to the interpretation of ventilation/perfusion lung scans.

Diagnosis of pulmonary embolism (PE) by visual interpretation of ventilation/perfusion (V/Q) scans is limited by the high percentages of patients classified in the intermediate- and low-probability categories. This study proposes a quantitative analysis of the distribution of V/Q ratios to better identify patients with PE. METHODS: We studied 99 consecutive patients who underwent dual-isotope (81m)Kr/(99m)Tc-macroaggregate V/Q scanning and arterial blood gas analysis within 48 h. The 8-view V/Q scans were visually analyzed by 2 observers according to the revised criteria of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) (normal scan or low, intermediate, or high probability of PE). Quantitative analysis of the posterior-view distribution histogram of V/Q ratios was performed using dedicated software. Briefly, regions of interest were drawn around the lungs on the matched V/Q images, smooth filtering was applied, normalized regional V/Q ratios were calculated within each pixel, and a distribution histogram was built. RESULTS: Patients with normal scans (n = 16) had a predominance of V/Q ratios (63.3% +/- 13.0%) between 0.8 and 1.2. They had only 9.8% +/- 5.8% of ratios > 1.2, and the remaining 26.9% +/- 7.5% of ratios were <0.8. By contrast, patients with PE (n = 34) were characterized by a significant increase (15.5 +/- 10.0%, P = 0.04) in high V/Q ratios (>1.2) and a significant increase (34.5% +/- 8.2%, P = 0.003) in low V/Q ratios (<0.8). Interestingly, a similar pattern was found in patients with a high PIOPED probability of PE, 21.3% +/- 11.0% and 37.5% +/- 9.2%, respectively. Within the nondiagnostic group (intermediate- + low-probability scans, n = 58), 17 patients were finally diagnosed with PE. Analysis of the distribution histogram in this group allowed the identification of 5 patients with PE (specificity, 78%). CONCLUSION: A quantitative approach to lung scan interpretation, based on the distribution histogram of V/Q ratios, may be helpful for categorizing patients with suspected PE.