肺通气/灌注显像与HCTPA诊断肺动脉栓塞的价值

目的　评价核素肺通气 灌注(V Q)显像、螺旋CT肺动脉造影(HCTPA)及血浆D 二聚体在诊断肺动脉血栓中的作用。方法　临床疑为肺动脉栓塞(PE)患者4 2例,男2 6例,女16例,平均年龄( 4 9 18±16 5 6 )岁,均行核素肺V Q显像、HCTPA及血浆D 二聚体测定。其中32例患者在行肺灌注显像时,选择双足背静脉注射肺灌注显像剂,同时完成双下肢静脉显像。结果　4 2例患者中34例经临床诊断为PE ,肺V Q显像诊断PE的灵敏度、准确性和阳性预测值分别为94 12 %、90 4 8%和94 12 % ,HCTPA分别为85 2 9%、83 33%和93 5 5 % ,D 二聚体分别为5 2 94 %、5 7 14 %和90 0 0 %。32例行下肢深静脉显像的PE患者中2 0例有下肢静脉血栓。结论　肺V Q显像无创、安全、简便,诊断PE的灵敏度、准确性高。核素肺显像诊断亚肺段水平PE的能力明显高于HCTPA。     

肺通气血流灌注显像、螺旋CT肺动脉造影及D-二聚体测定对诊断肺栓塞的临床价值

目的探讨放射性核素肺通气血流灌注比值(V/Q)显像和螺旋CT肺动脉造影(SCTPA)以及血浆D-二聚体(dimer)检测对肺栓塞(PE)诊断的临床价值。方法对我院2010年2月—2013年2月可疑肺栓塞的患者,行V/Q显像、SCTPA检查和血浆D-二聚体测定以及相关检查,以最终临床诊断为依据,分别评价V/Q显像、SCTPA和血浆D-二聚体测定对PE的诊断价值。结果 278例高度怀疑PE患者经上述检查确诊PE患者151例,V/Q显像、SCTPA检查和血浆D-二聚体测定诊断PE的灵敏度、特异性、阳性预测值、阴性预测值分别为93.6%(132/141)、96.0%(120/125)、96.4%(132/137)、93.0%(120/129);95.8%(137/143)、96.9%(124/128)、97.2%(137/141)、95.4%(124/130);99.3%(140/141)、43.1%(59/137)、64.2%(140/218)、98.3%(59/60)。结论血浆D-二聚体测定的价值主要用于排除PE。对PE患者的检查应力求全面,V/Q显像、SCTPA检查均有其优点和不足,只有全面掌握各项检查的特点,才能对该项检查对疾病的诊断价值做出正确评价,从而正确运用这一诊断方法更好地服务于临床。     

肺灌注/通气显像与肺动脉造影诊断肺动脉栓塞的对比研究

目的评价核素肺通气/灌注(V/Q)显像在肺动脉栓塞(PE)诊断中的价值。方法临床疑有PE患者30例,男女各15例,平均年龄(38.2±13.9)岁。均行胸部X线片检查、核素V/Q显像和肺动脉造影。11例患者在行肺灌注显像时,选择双侧足背静脉注射肺灌注显像剂,同时完成双下肢静脉显像。结果30例患者中22例V/Q显像示不相匹配的肺叶、肺段或多发亚肺段的放射性分布稀疏或缺损,提示为PE;但肺动脉造影证实22例中20例为PE。8例患者的V/Q显像为相匹配的肺叶、肺段或多发亚肺段的稀疏或缺损,提示不是PE,与肺动脉造影结果一致。核素V/Q显像诊断PE的灵敏度为100%（20/20例）,特异性为80.0%（8/10例）,准确性为93.3%（28/30例）。X线胸片和核素下肢静脉显像有助于PE的正确诊断。结论多数PE患者通过核素肺V/Q显像结合X线胸片可以作出明确诊断,少数肺V/Q显像与临床表现不符的患者需行肺动脉造影。     

肺V/Q SPECT/CT显像对肺栓塞诊断价值研究

目的探讨肺V/Q SPECT/CT显像对肺栓塞的诊断价值。方法回顾性分析北部战区总医院自2016年11月至2017年10月收治的186例可疑肺栓塞患者的临床资料。所有患者均行肺Q SPECT/CT、肺V/Q SPECT、肺V/Q SPECT/CT显像,比较3种显像方法的灵敏度、特异性、准确性、阳性预测值、阴性预测值,分析其对肺栓塞的诊断效能。结果 186例可疑肺栓塞患者中,66例符合肺栓塞诊断标准,可以确诊。肺Q SPECT/CT显像的灵敏度、特异性、准确性、阳性预测值、阴性预测值分别为92.4%(61/66)、74.2%(89/120)、80.6%(150/186)、66.3%(61/92)、94.7%(89/94),肺V/Q SPECT显像分别为90.9%(60/66)、80.8%(97/120)、84.4%(157/186)、72.3%(60/83)、94.2%(97/103),肺V/Q SPECT/CT显像分别为92.4%(61/66)、92.5%(111/120)、92.5%(172/186)、87.1%(61/70)、95.7%(111/116)。肺Q SPECT/CT、肺V/Q SPECT显像的准确性均明显低于肺V/Q SPECT/CT显像,差异有统计学意义(P<0.05)。肺Q SPECT/CT显像的特异性明显低于肺V/Q SPECT/CT显像,差异有统计学意义(P<0.05)。结论肺V/Q SPECT/CT显像对肺栓塞的诊断效能高于肺Q SPECT/CT、肺V/Q SPECT显像,可提高诊断的准确性和特异性。     

SPECT/CT同机图像融合技术诊断肺动脉栓塞的临床价值

目的探讨SPECT/CT同机图像融合技术对肺动脉栓塞(PE)的诊断价值。方法选择58例可疑肺动脉栓塞(PE)患者,分别进行肺通气/灌注(V/P)显像、螺旋CT血管造影(SCTA)、SPECT/CT同机扫描以及图像融合处理,比较对PE诊断的灵敏度和特异性及准确性的差异。结果V/P显像,SCTA,SPECT/CT对PE诊断的灵敏度、特异性及准确性分别为90.00%、64.29%、77.59%;73.33%、85.71%、79.31%;90.00%、85.71%、87.93%。结论总体看,在PE诊断中,SPECT/CT融合图像技术准确性优于SCTA和V/P显像。     

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.     

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.     

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。     

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.     

Pulmonary embolism: is scintigraphy useful after initial angio-CT?

PURPOSE: To assess the value of ventilation-perfusion scintigraphy after an initial helical CT with absence of pulmonary embolism (PE). MATERIAL: and methods. Twenty eight consecutive patients with clinical suspicion of pulmonary embolism underwent helical CT scan to look for an intra-luminal clot. When the CT-scan was positive for PE, diagnosis was retained. If the result was negative, a ventilation-perfusion scintigraphy was performed. If the result was also negative, diagnosis of PE was excluded. In case of discrepancy, a pulmonary angiography was performed and used as gold-standard. RESULTS: Twenty-one patients showed PE at CT-angio and 7 did not. Two of these 7 had normal or low probability scintigraphy, excluding diagnosis of PE. One had intermediate V/P scan and 4 had high probability V/P scan. For these 5 discrepancies, none of them had PE on angiography. CONCLUSION: In this population, scintigraphy was not appropriate after a negative CT-angio for PE. In case of persistent doubt after a normal initial helical CT, pulmonary angiography is required     

Diagnosis of pulmonary embolism with spiral CT as a second procedure following scintigraphy

Our objective was to evaluate, in a routine clinical setting, the role of spiral CT as a second procedure in patients with clinically suspected pulmonary embolism (PE) and abnormal perfusion scan. We prospectively studied the role of spiral CT in 279 patients suspected of PE. All patients started their diagnostic algorithm with chest radiographs and perfusion scintigraphy. Depending on the results of perfusion scintigraphy, patients proceeded to subsequent levels in the algorithm: stop if perfusion scintigraphy was normal; CT and pulmonary angiography if subsegmental perfusion defects were seen; ventilation scintigraphy followed by CT when segmental perfusion defects were seen; and pulmonary angiography in this last group when results of ventilation/perfusion scintigraphy and CT were incongruent. Reference diagnosis was based on normal perfusion scintigraphy, high probability perfusion/ventilation scintigraphy in combination with abnormal CT, or pulmonary angiography. If PE was present, the largest involved branch was noted on pulmonary angiography, or on spiral CT scan in case of a high-probability ventilation/perfusion scan and a positive CT scan. A distinction was made between embolism in a segmental branch or larger, or subsegmental embolism. Two hundred seventy-nine patients had abnormal scintigraphy. In 27 patients spiral CT and/or pulmonary angiography were non-diagnostic and these were excluded for image analysis. Using spiral CT we correctly identified 117 of 135 patients with PE, and 106 of 117 patients without PE. Sensitivity and specificity was therefore 87 and 91%, respectively. Prevalence of PE was 53%. Positive and negative predictive values were, respectively, 91 and 86%. In the high-probability group, sensitivity and specificity increased to 97 and 100%, respectively, with a prevalence of 90%. In the non-high probability-group sensitivity and specificity decreased to 61 and 89%, respectively, with a prevalence of 25%. In a routine clinical setting single-detector spiral CT technology has limited value as a second diagnostic test because of low added value in patients with a high-probability lung scan and low sensitivity in patients with non-high-probability lung scan result.     

多排螺旋CT肺血管成像结合血浆D-二聚体测定对肺动脉栓塞的诊断价值

目的探讨多排螺旋CT肺血管成像(MSCTPA)结合血浆D-二聚体(D-dimer,DD)测定在肺动脉栓塞(pulmonaryem-bolism,PE)诊断中的应用价值方法对48例临床可疑PE患者进行MSCTPA检查和血浆DD检测以临床诊断为依据,分别评价MSCTPA、DD测定及MSCTPA结合血浆DD测定对PE的诊断价值其中22例病人于MSCTPA检查结果阳性后即进行溶栓治疗,并于治疗后第2天、第3天、第7天及2周分别复查DD值,于治疗后2周内分别复查了1次MSCTPA结果DD测定值全部阳性(48例),阳性率100%;MSCTPA共检出PE45例,3例无明显栓塞征象(2例肺内见片状炎性浸润影,1例两肺见散在纤维束条影),45例PE中1例MSCTPA首诊结果可疑,在DD阳性的提示下行0.625mm薄层重建肯定了PE的诊断溶栓治疗后复查的22例中,13例于1周内DD测定值升高,1周后DD测定值下降,9例DD值变化不明显;MSCTPA复查中DD值先升高后下降的13例充盈缺损征象明显改善,9例DD值变化不明显者充盈缺损征象亦无明显变化结论MSCTPA和血浆DD测定结合可提高PE的检出率,对诊断PE具有重要的临床应用价值     

Diagnosis of acute pulmonary embolism in outpatients: comparison of thin-collimation multi-detector row spiral CT and planar ventilation-perfusion scintigraphy

PURPOSE: To compare multi-detector row computed tomography (CT) and ventilation-perfusion (V-P) scintigraphy in the diagnosis of acute pulmonary embolism (PE) in outpatients who were cared for in the emergency department. MATERIALS AND METHODS: Ninety-four nonconsecutive patients, in whom acute PE was suspected, underwent thin-collimation multi-detector row CT (collimation, 4 x 1 mm; pitch, 1.25; scanning time, 0.5 second) and V-P scintigraphy. Concordance between CT and scintigraphic images was used in the diagnosis of PE. Pulmonary angiography was performed within 24 hours if interpretations of V-P and spiral CT images were inconclusive or discordant. Sensitivity and specificity values were calculated for V-P scintigrams and CT scans of the lungs. The rates of conclusive results for scintigraphy and CT were compared. RESULTS: The sensitivity of thin-collimation multi-detector row CT and V-P scintigraphy for the detection of PE was 96% (27 of 28; CI: 82%, 99%) and 98% (65 of 66; CI: 92%, 99%), respectively. The specificity of CT and V-P scintigraphy was 86% (24 of 28; CI: 67%, 96%) and 88% (58 of 66; CI: 77%, 94%), respectively. Seven V-P scintigrams were of intermediate probability, and one spiral CT study was indeterminate. Examinations with spiral CT yielded conclusive results more often than examinations with planar V-P scintigraphy (P <.05). Five V-P scintigrams and spiral CT scans were discordant. Twelve pulmonary angiographic examinations were performed. Angiographic findings were concordant in 10 (91%) of 11 patients with conclusive CT scans in whom pulmonary angiography was attempted. CT was used to establish an alternative diagnosis in 19 (29%) of 66 patients in whom PE was excluded. CONCLUSION: Thin-collimation multi-detector row CT is more accurate than V-P scintigraphy in the diagnosis of acute PE in outpatients. Furthermore, CT provides alternative diagnoses for patients without PE on high-quality transverse or near-isotropic reformatted images.     

Kr-81m ventilation imaging: clinical utility in suspected pulmonary embolism

The results of Kr-81m/Tc-99m ventilation-perfusion (VP) lung scintigraphy were correlated with the results of pulmonary angiography for 74 patients suspected of having pulmonary embolism (PE). Among patients having a diagnostic scan, the sensitivity and specificity of scintigraphy were 91% and 94%, respectively. Also, 157 consecutive cases of Kr-81m/Tc-99m VP lung scintigraphy were reviewed, and the frequency of an indeterminate scan was found to be 22%. A similar frequency was found for VP scintigraphy with xenon-133. Of eight patients who had indeterminate scans due to the presence of a single VP mismatch, four were demonstrated to have PE by angiography. Kr-81m is an excellent agent for VP scanning in cases of suspected PE, offering accuracy in diagnosis as well as favorable physical properties.     

Scintigraphic probability and angiographic diagnostic certainty in acute pulmonary embolism

The objectives of this study were to determine if diagnostic certainty on angiography correlates with scintigraphic probability for the diagnosis of pulmonary embolism. From a total of 160 consecutive patients who underwent both nuclear imaging and invasive selective pulmonary angiography, we reviewed the xenon-133 ventilation images in 2 posterior oblique views and the Tc-99m macroaggregated serum albumin perfusion scans and angiograms of 40 patients (15 men, 25 women; average age 57 years) who were discharged from the hospital on anticoagulants with a diagnosis of pulmonary embolism. The angiograms were reviewed and the diagnosis of embolism was considered certain in the presence of an intraluminal filling defect, a trailing embolus, or a branch occlusion equal to or larger than a segmental branch (n=29; 73%), and uncertain when the studies were reinterpreted as either equivocal or negative or in the presence of a single, small subsegmental filling defect of questionable clinical significance. The ventilation-perfusion scans were read as high (n=18; 45%), intermediate (n=10; 25%), or low (n=12; 30%) probability. The proportion of patients with diagnostic certainty on angiography in the high-, intermediate-, and low-probability scintigraphic subgroups was, respectively, 100% (18 of 18), 70% (7 of 10), and 33% (4 of 12) (P=0.004). In patients diagnosed with pulmonary embolism based on selective angiography, a lower probability of pulmonary embolism on ventilation-perfusion scintigraphy correlates with a lesser degree of diagnostic certainty on angiography and a higher incidence of single subsegmental emboli.     

Complementarity of lung scintigraphy and D-dimer test in pulmonary embolism

D-dimer assay (DDA), measuring fibrin degradation products, was compared with lung scintigraphy (LS) in a prospective unselected series of 83 consecutive patients referred owing to suspicion of pulmonary embolism (PE). This patient series was also used to compare several methods of performing and interpreting LS images. The final diagnosis was established independently by a separate panel with all available information except for the result of DDA. D-dimer was determined by ELISA (threshold value 500 ng/ml). LS, including perfusion (Q) and pseudo-ventilation (Technegas) (V), was classified according to PIOPED, (1) immediately by the physician on duty, and (2) retrospectively by a blinded panel. A positive (19) or negative (61) diagnosis of PE was achieved in 80 patients, the prevalence of PE being 24%. Only one false-negative was noted on DDA (sensitivity=95%) but there were 42 false-positives (specificity=31%), resulting in a positive predictive value of 30% and a negative predictive value of 95%. Emergency and retrospective interpretations of LS were close (kappa=0.4). In a minority of patients, PE may be excluded with reasonable certainty if DDA is normal, resulting in a significant saving in terms of time and money.     

双能量CT肺灌注及血管成像与核素肺通气灌注成像诊断肺栓塞的对照研究

目的 通过与核素肺通气灌注显像比较,评价双能量CT肺血管成像(DE-CTPA)及双能量CT肺灌注成像(DE-CTLP)技术诊断肺栓塞的能力.方法 比较50例临床怀疑肺栓塞的患者DE-CTPA、DE-CTLP及核素肺通气灌注显像结果,以非线性相关检验比较DE-CTPA显示肺血管腔内充盈缺损与DE-CTLP显示灌注缺损之间的相关性,以核素为参考标准,应用一致性检验方法(Kappa检验)对照分析两者之间的一致性及DE-CTLP诊断肺栓塞的敏感性和特异性.结果 (1)50例临床怀疑肺栓塞患者中,4例CT图像质量差,不能评价.余46例共920个有效肺段中,DE-CTPA显示262个肺段肺血管腔内充盈缺损,DE-CTLP显示266个肺段明确灌注缺损.核素肺通气灌注扫描显示268个肺段灌注与通气不匹配.(2)DE-CTLP与DE-CTPA两者间显著相关(r=0.883,P<0.01);DE-CTLP与核素肺通气灌注显像的一致性良好(Kappa=0.940,P<0.01);以核素肺通气灌注成像为诊断参考标准,应用DE-CTLP诊断肺栓塞的阳性预测值95.5%(279/292),阴性预测值98.3%(641/652),敏感性96.2%(279/290),特异性98.0%(641/654).(3)应用CareDose 4D技术,DE-CTPA和DE-CTLP患者平均射线损伤剂量为(4.37±0.47)mSv.结论 应用DE-CTPA和DE-CTLP技术可以在一次扫描中同时获得常规CT肺血管成像的血管形态学信息和肺实质血流灌注情况,为临床诊断肺栓塞提供直观、有效的综合影像信息.     

MR肺通气联合灌注成像的动物模型研究

目的 探讨氧增强MR肺通气成像联合肺灌注成像诊断气道阻塞和肺栓塞(PE)病变的可行性和价值。方法 对8只犬通过肺段动脉水平注入凝胶海绵颗粒复制周围型PE模型，其中5只经自制球囊导管插入二级气道又建立气道阻塞模型。通过吸纯氧前后的图像减影可获得氧增强MR肺通气图像。利用对比剂首次通过法可进行MR肺灌注成像。观察MR肺通气和灌注成像的表现，并与大体病理解剖、核素肺通气-灌注成像和肺血管造影进行对照。结果 MR肺通气和灌注成像在气道阻塞区的表现相匹配，但在肺栓塞区不匹配。气道阻塞区在MR肺通气成像中的缺损区域小于核素肺通气成像。根据信号强度随时间变化曲线，肺灌注异常区可分为灌注缺损和减低区。MR肺通气联合灌注成像诊断肺栓塞的敏感度和特异度分别为75．0％和98．1％；其诊断结果与核素肺通气一灌注成像和肺血管造影的一致性较好(K=0．743、0．899)。结论 氧增强MR肺通气成像联合肺灌注成像可用来诊断肺内气道和血管异常，该方法与核素肺通气-灌注成像类似，并能提供量化的功能信息和更高的时间、空间分辨率，具有临床应用价值。     

Improving the diagnostic performance of lung scintigraphy in suspected pulmonary embolic disease

AIM: to determine the effectiveness of a new imaging algorithm in the investigation of suspected pulmonary embolism (PE). MATERIALS AND METHODS: A new imaging algorithm for suspected PE was introduced following the installation of a multisection computed tomography (CT) machine at our institution. Before its installation, patients with suspected PE were evaluated with ventilation/perfusion (V/Q) scintigraphy. Subsequently, patients were triaged according to chest radiography (CR) and respiratory history to either lung scintigraphy or CT pulmonary angiography (CTPA). Patients with a normal CR and no history of lung disease were evaluated using perfusion (Q) scintigraphy [ventilation (V) scintigraphy was no longer performed]. Patients with an abnormal CR, asthma or chronic lung disease were evaluated using CTPA. All V/Q images in a continuous 3-year period before the introduction of the new imaging algorithm and all Q images performed in a 3-year period after its introduction were retrospectively reviewed. Imaging reports were categorized into normal, non-diagnostic (low or intermediate probability) or high probability for PE. Patients in the later group who subsequently underwent CTPA, were also reviewed. RESULTS: After the policy change the percentage of normal scintigrams significantly increased (39 to 60%; p<0.001). There was a non-significant increase in the percentage of high probability scintigrams (15 to 18%; p=0.716). Overall the diagnostic yield of lung scintigraphy improved significantly (54 to 78%; p<0.001). CONCLUSION: the diagnostic performance of lung scintigraphy can be improved by careful triage of patients to either Q scintigraphy or CTPA based on clinical history and CR findings. Q scintigraphy remains a valuable diagnostic test in the investigation of suspected PE in carefully selected patients.