Role of pulmonary perfusion magnetic resonance imaging for the diagnosis of pulmonary hypertension:A review

Among five types of pulmonary hypertension,chronic thromboembolic pulmonary hypertension(CTEPH)is the only curable form,but prompt and accurate diagnosis can be challenging.Computed tomography and nuclear medicine-based techniques are standard imaging modalities to non-invasively diagnose CTEPH,however these are limited by radiation exposure,subjective qualitative bias,and lack of cardiac functional assessment.This review aims to assess the methodology,diagnostic accuracy of pulmonary perfusion imaging in the current literature and discuss its advantages,limitations and future research scope.

Determination of the degree of pulmonary arteryhypertension by plasma atrial nateiuretic peptide levelsand pulmonary perfusion imaging

To evaluate the degree of pulmonary artery hypertension (PAH) and its significance, pulmonary perfusion tomographic imaging (PPTI) and radioimmunoassay of plasma atrial nateiuretic peptide (ANP) levels were examined in different stages of rabbit PAH models, controlled with cardiac catheterization. When the PAH was mild, ANP levels were not significantly changed (t= 1, p >0.05). The mean pulmonary artery pressures (mPAP) measured by catheterization had no significant change, but there was a significant increase of the ratio of dorsal/abdominal counts using pulmonary perfusion tomographic imaging (PPTI) (t=2.5, p <0.05). The ANP levels rose when PAH was moderate or severe, and the difference was significant compared with the control group (t=4 and 6.5, p <0.05). The other two methods also showed significant changes (p <0.01). There was positive correlation between the results of ANP/PPTI, ANP/catheterization, and PPTI/catheterizations (p <0.01). These results suggest that ANP levels can assess the degree of the PAH as a simple method, but it is not as sensitive as that of the PPTI in mild PAH.

Correlation analysis of dual-energy CT iodine maps with quantitative pulmonary perfusion MRI

AIM:To correlate dual-energy computed tomography(DECT) pulmonary angiography derived iodine maps with parameter maps of quantitative pulmonary perfusion magnetic resonance imaging(MRI).METHODS:Eighteen patients with pulmonary perfusion defects detected on DECT derived iodine maps were included in this prospective study and additionally underwent time-resolved contrast-enhanced pulmonary MRI [dynamic contrast enhanced(DCE)-MRI].DCE-MRI data were quantitatively analyzed using a pixel-by-pixel deconvolution analysis calculating regional pulmonary blood flow(PBF),pulmonary blood volume(PBV) and mean transit time(MTT) in visually normal lung parenchyma and perfusion defects.Perfusion parameterswere correlated to mean attenuation values of normal lung and perfusion defects on DECT iodine maps.Two readers rated the concordance of perfusion defects in a visual analysis using a 5-point Likert-scale(1 = no correlation,5 = excellent correlation).RESULTS:In visually normal pulmonary tissue mean DECT and MRI values were:22.6 ± 8.3 Hounsfield units(HU);PBF:58.8 ± 36.0 mL/100 mL per minute;PBV:16.6 ± 8.5 mL;MTT:17.1 ± 10.3 s.In areas with restricted perfusion mean DECT and MRI values were:4.0 ± 3.9 HU;PBF:10.3 ± 5.5 mL/100 mL per minute,PBV:5 ± 4 mL,MTT:21.6 ± 14.0 s.The differences between visually normal parenchyma and areas of restricted perfusion were statistically significant for PBF,PBV and DECT(P < 0.0001).No linear correlation was found between MRI perfusion parameters and attenuation values of DECT iodine maps(PBF:r = 0.35,P = 0.15;PBV:r = 0.34,P = 0.16;MTT:r = 0.41,P = 0.08).Visual analysis revealed a moderate correlation between perfusion defects on DECT iodine maps and the parameter maps of DCE-MRI(mean score 3.6,k 0.45).CONCLUSION:There is a moderate visual but not statistically significant correlation between DECT iodine maps and perfusion parameter maps of DCE-MRI.

Preliminary study on CT perfusion imaging in guiding biopsy of pulmonary lumps

Background CT perfusion imaging （CTP） has been proved to be a powerful functional imaging technique. This study aimed to evaluate the value of CTP in guiding biopsy of pulmonary lumps. Methods A total of 147 patients with pulmonary lumps who had CT guided biopsies were enrolled in this study from February 2005 to June 2007. The patients were assigned to 3 groups： 33 cases guided by CTP as group 1, 45 cases guided by contrast-enhanced scan of CT as group Ⅱ, and 69 cases guided by plain scan of CT as group Ⅲ. Each group was subdivided into central and peripheral types according to the location of the lumps. The achievement ratio of biopsy, the accuracy in grouping, and grading of lung cancer, and the incidence of complication were compared. Results The total achievement ratios of biopsy from group Ⅰ to Ⅲ were 100% （33/33）, 91% （41/45）, and 80% （55/69） respectively, and the difference was statistically significant between group Ⅰ and Ⅲ （P 〈0.05）. For the central type, they were 100% （18/18）, 88% （15/17）, and 79% （11/14） respectively, and the difference was also statistically significant between group Ⅰand Ⅲ （P 〈0.05）. For the peripheral type, they were 100% （15/15）, 93% （26/28）, and 80% （44/55） respectivelies, and the difference was not statistically significant among the three groups. The total accuracies in grouping and grading of lung cancer from group Ⅰ to Ⅲ were 100% （27/27）, 91% （31/34）, and 72% （33/46） respectively, and the difference was statistically significant between group Ⅰ and Ⅲ and between group Ⅱ and Ⅲ （P 〈0.05）. For the central type, they were 100% （16/16）, 94% （16/17）, and 70% （8/12） respectively, and the difference was statistically significant between group Ⅰ and Ⅲ （P〈0.05）. For the peripheral type, they were 100% （11/11）, 88% （15/17）, and 72% （26/36） respectively, and the difference was statistically significant between group Ⅰ and Ⅲ （P 〈0.05）. The total incidence of complication from group Ⅰ to Ⅲ were 15% （5/33）, 27% （12/45）, and 43% （30/69） respectively, and the difference was statistically significant between group Ⅰ and Ⅲ （P 〈0.01）. For the central type, they were 11% （2/18）, 24% （4/17）, and 57% （8/14） respectively, and the difference was statistically significant between group Ⅰ and Ⅲ （P 〈0.01）. For the peripheral type, they were 20% （3/15）, 29% （8/28）, and 40% （22/55） respectively, and no statistically significant difference was found among the three groups. Conclusions CTP guided biopsy of pulmonary lumps using multi-detector row CT has the potential to improve the accuracy of histopathological diagnosis with a lower risk and higher achievement ratio. More research and technical improvements are needed before it is widelv used.

Pulmonary functional MRI: an animal model study of oxygen-enhanced ventilation combined with Gd-DTPA-enhanced perfusion

Background The assessment of regional pulmonary ventilation and perfusion is essential for the evaluation of a variety of lung disorders. Pulmonary ventilation MRI using inhaled oxygen as a contrast medium can be obtained with a clinical MR scanner, without additional equipment, and has been demonstrated to be a feasible means of assessing ventilation in animal models and some clinical patients. However, few studies have reported on MR ventilation-perfusion imaging. In this study, we evaluated the usefulness of oxygen-enhanced ventilation in combination with first-pass Gd-DTPA-enhanced perfusion MRI in a canine model of pulmonary embolism and airway obstruction.Methods Peripheral pulmonary embolisms were produced in eight dogs by intravenous injection of gelfoam strips at the pulmonary segmental arterial level, and airway obstructions were created in five of the dogs by inserting a self-designed balloon catheter into a secondary bronchus. Oxygen-enhanced MR ventilation images were produced by subtracting images from before and after inhalation of pure oxygen. Pulmonary perfusion MR images were acquired with a dynamic three-dimensional fast gradient-echo sequence. MR ventilation and perfusion images were read and contrasted with results from general examinations of pathological anatomy, ventilation-perfusion scintigraphy, and pulmonary angiography. Results Regions identified as having airway obstructions matched using both MR ventilation and perfusion imaging, but regions of pulmonary embolisms were mismatched. The area of airway obstruction defects was smaller using MR ventilation imagery than that using ventilation scintigraphy. Abnormal perfusion regions due to pulmonary embolisms were divided into defective regions and reduced regions based on the time course of signal intensity changes. In the diagnosis of pulmonary embolisms with the technique of ventilation and perfusion MRI, sensitivity and specificity were 75.0% and 98.1%, respectively, and the diagnostic results of this MRI technique were in agreement with the results of ventilation-perfusion scintigraphy and pulmonary angiography (K: 0.899, 0.743).Conclusions Oxygen-enhanced ventilation in combination with pulmonary perfusion MRI can be used to diagnose abnormalities of airways and blood vessels in the lungs, and can provide regional functional information with high spatial and temporal resolution. This method possesses great potential value for clinical applications. F

Role of MR-DWI and MR-PWI in the radiotherapy of implanted pulmonary VX-2 carcinoma in rabbits

Objective： To detect the activity of tumor cells and tumor blood flow before and after the radiotherapy of implanted pulmonary VX-2 carcinoma in rabbit models by using magnetic resonance diffusion-weighted imaging（MR-DWI） and magnetic resonance perfusion weighted imaging（MR-PWI）, and to evaluate the effectiveness and safety of the radiotherapy based on the changes in the MR-DWI and MR-PWI parameters at different treatment stages.Methods： A total of 56 rabbit models with implanted pulmonary VX-2 carcinoma were established, and then equally divided into treatment group and control group. MR-DWI and MR-PWI were separately performed using a Philips Acheiva 1.5T MRI machine（Philips, Netherland）. MRI image processing was performed using special perfusion software and the WORKSPACE advanced workstation for MRI. MRDWI was applied for the observation of tumor signals and the measurement of apparent diffusion coefficient（ADC） values; whereas MR-PWI was used for the measurement of wash in rate（WIR）, wash out rate（WOR）, and maximum enhancement rate（MER）. The radiation treatment was performed using Siemens PRIMUS linear accelerator. In the treatment group, the radiotherapy was performed 21 days later on a once weekly dosage of 1,000 c Gy to yield a total dosage of 5,000 c Gy.Results： The ADC parameters in the region of interest on DWI were as follows： on the treatment day for the implanted pulmonary VX-2 carcinoma, the t values at the center and the edge of the lesions were 1.352 and 1.461 in the treatment group and control group（P〉0.05）. During weeks 0-1 after treatment, the t values at the center and the edge of the lesions were 1.336 and 1.137（P〉0.05）. During weeks 1-2, the t values were 1.731 and 1.736（P〈0.05）. During weeks 2-3, the t values were 1.742 and 1.749（P〈0.05）. During weeks 3-4, the t values were 2.050 and 2.127（P〈0.05）. During weeks 4-5, the t values were 2.764 and 2.985（P〈0.05）. The ADC values in the treatment group were significantly higher than in the control group. After the radiotherapy（5,000 c Gy）, the tumors remarkably shrank, along with low signal on DWI, decreased signal on ADC map, and remarkably increased ADC values. As shown on PWI, on the treatment day for the implanted pulmonary VX-2 carcinoma, the t values of the WIR, WOR, and MER at the center of the lesions were 1.05, 1.31, and 1.33 in the treatment group and control group（P〉0.05）; in addition, the t values of the WIR, WOR, and MER at the edge of the lesions were 1.35, 1.07, and 1.51（P〉0.05）. During weeks 0-1 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 1.821, 1.856, and 1.931（P〈0.05）; in addition, the t values of the WIR, WOR, and MER at the edge of the lesions were 1.799, 2.016, and 2.137（P〈0.05）. During weeks 1-1 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 2.574, 2.156, and 2.059（P〈0.05） and the t values of the WIR, WOR, and MER at the edge of the lesions were 1.869, 2.058, and 2.057（P〈0.05）. During weeks 2-3 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 2.461, 2.098, and 2.739（P〈0.05） and the t values of the WIR, WOR, and MER at the edge of the lesions were 2.951, 2.625, and 2.154（P〈0.05）. During weeks 3-4 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 2.584, 2.107, and 2.869（P〈0.05） and the t values of the WIR, WOR, and MER at the edge of the lesions were 2.057, 2.637, and 2.951（P〈0.05）. During weeks 4-5 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 2.894, 2.827, and 3.285（P〈0.05） and the t values of the WIR, WOR, andMER at the edge of the lesions were 3.45, 3.246, and 3.614（P〈0.05）. After the radiotherapy（500 c Gy）, the tumors shrank on the T1 WI, WIR, WOR, and MER; meanwhile, the PWI parameter gradually decreased and reached its minimum value.Conclusions： MR-DWI and MR-PWI can accurately and directly reflect the inactivation of tumor cells and the tumor hemodynamics in rabbit models with implanted pulmonary VX-2 carcinoma, and thus provide theoretical evidences for judging the clinical effectiveness of radiotherapy for the squamous cell carcinoma of the lung.

PULMONARY BLOOD DISTRIBUTION AFTER TOTAL CAVOPULMONARY CONNECTION OF DIFFERENT TYPES

Objective.To assess the feature of pulmonary blood flow distribution after total cavopulmonary connection(TCPC)of different types,and to provide the selection of the best type.Methods. Thirty-two consecutive survival patients after TCPC underwent radionuclide lung perfusion imaging. According to the radionuclide counts in the left and right lungs,analyses of the distribution of blood flow from superior venous cava(SVC) and inferior venous cava(IVC)and the whole pulmonary blood flow in both lungs were made. All patients were divided into 4 groups by the the anastomosis between IVC and pulmonary artery.Results. GroupⅠ:The flow ratio of the IVC to left lung was greater than that to the right lung,P≤0.01;the flow ratio of the SVC to right lung was greater than that to the left lung,P≤0.01;and the whole pulmonary blood flow went dominantly to the left lung,P≤0.05,which is not in line with physiological distribution. GroupⅡ:the flows from the SVC and IVC were mixed in the middle of the junction and ran evenly into the right and left lungs,the whole pulmonary blood flow went to both lungs,P≥0.05. Group Ⅲ:the flow ratio of the SVC to both lungs were the same,P≥0.05,and major part from IVC went to the right lung,P≤0.01;the pulmonary blood flow go dominantly to the right lung,P≤0.05,which is in accord with physiological distribution. Group Ⅳ:the flows from the right SVC went to right lung by 100%,P≤0.01,and that from the left SVC went to left lung by 100% too,P≤0.01;the flows from IVC went dominantly to the left lung,with little part to the right lung ,P≤0.05.Conclusions. Different types of TCPC can result in different pulmonary blood distributions. The best flow distribution between the left and right lungs can be obtained by an offset of the IVC anastomosis toward the RPA with widening anastomosis for the patients without persist left superior venous cava(PLSVC).

职业性尘肺病患者胸部CT影像表现与肺通气功能的相关性

目的探讨职业性尘肺病患者胸部CT影像表现与肺通气功能相关性。方法选取2019年1月至2021年12月焦作市疾病预防控制中心收集的86例职业性尘肺病患者纳入尘肺病组,早期煤尘肺病HRCT分期法分为Ⅰ期33例、Ⅱ期29例和Ⅲ期24例,另选取86例同期行健康体检者纳入健康对照(HC)组,均接受胸部CT检查和肺通气功能检查,采用Camiciotoli视觉评分法评估两组胸部CT影像肺间质纤维化评分,记录呼气流量峰值(PEF)、第1秒用力呼气容积(FEV_(1))、FEV_(1)/用力肺活量(FCV)、最大自主通气量(MMV)。分析职业性尘肺病患者胸部CT影像表现;比较尘肺病组和HC组胸部CT影像肺纤维化评分和肺通气功能指标水平;比较不同分期职业性尘肺病患者胸部CT影像肺纤维化评分和肺通气功能指标水平;Pearson相关性分析职业性尘肺病患者胸部CT影像肺纤维化评分与肺通气功能指标的关系。结果职业性尘肺病患者胸部CT影像主要表现为小结节影、小结节聚集、纤维斑块形和小叶间隔增厚、胸膜斑;尘肺病组胸部CT影像肺纤维化评分为(20.16±5.01)分,其FEV_(1)、PEF、FEV_(1)/FVC值、MVV低于HC组(P<0.05);Ⅲ期职业性尘肺病患者胸部CT影像肺纤维化评分高于Ⅰ期、Ⅱ期患者,FEV_(1)、PEF、FEV_(1)/FVC值、MVV低于Ⅰ期、Ⅱ期患者(P<0.05);Pearson相关性分析,职业性尘肺病患者胸部CT影像肺纤维化评分与FEV_(1)、PEF、FEV_(1)/FVC值、MVV呈负相关(r=-0.625,-0.865,-0.636,-0.673,P<0.05)。结论职业性尘肺病患者胸部CT影像肺纤维化评分与肺通气功能指标之间存在负相关性,可作为临床判断职业性尘肺病和评估病情进展的可靠的影像学指标。

对比肺通气/灌注显像和CT肺动脉造影对急性肺栓塞患者发生慢性血栓栓塞性肺动脉高压的预测价值

目的:比较肺通气/灌注(ventilation/perfusion,V/Q)显像和CT肺动脉造影(pulmonary angiography,PA)预测急性肺栓塞(acute pulmonary embolism,APE)后慢性血栓栓塞性肺动脉高压(chronic thromboembolic pulmonary hypertension,CTEPH)发生的价值。方法:回顾性收集了2012年1月至2020年8月,确诊为APE患者的资料,所有患者经至少3个月规范化抗凝后复查肺V/Q显像和CTPA。分别评估并计算肺V/Q显像和CTPA图像中的残余肺栓塞,并分别记录为肺灌注缺损百分比(percentage of pulmonary defect scores,PPDs%)和CT肺动脉阻塞指数(pulmonary artery obstruction index,PAOI)。评价PPDs%和CTPAOI预测CTEPH发生的一致性。绘制受试者工作特征(ROC)曲线,评估PPDs%和CTPAOI对APE后CTEPH发生的预测效能。结果:共纳入224例APE患者,1年内随访,共有26例进展为CTEPH。Bland-Altman图示两检查评估APE治疗后残余肺栓塞的一致性较好。ROC分析示PPDs%的AUC>CTPAOI(0.958 vs.0.868,P=0.03);预测CTEPH发生的阈值分别为20.5%和15.0%,相应的敏感性和特异性分别为92.3%、88.9%和76.9%、89.4%,差异均无统计学意义(敏感性:P=0.13;特异性:P>0.999)。结论:肺V/Q显像预测APE后CTEPH发生率比CT PA更敏感,但特异性略低。

MSCT灌注成像参数鉴别诊断孤立性肺结节良恶性的价值

目的:探讨多层螺旋CT(multi-slice spiral CT,MSCT)灌注成像参数鉴别诊断孤立性肺结节(solitary pulmonary nodules,SPN)良恶性的价值。方法:选取2021年10月至2022年10月我院收治的80例SPN患者,所有患者入院后均行MSCT灌注成像检查、病理检查。根据组织病理学检查结果将患者分为良性结节组和恶性结节组。比较2组患者的MSCT灌注成像参数(血容量、平均通过时间、血流量、表面渗透系数),采用受试者工作特征曲线分析MSCT灌注成像参数鉴别诊断SPN良恶性的价值。结果:80例SPN患者中,经组织病理学检查确诊47例为恶性结节,33例为良性结节。2组患者MSCT灌注成像参数中的平均通过时间比较,差异无统计学意义(P>0.05);恶性结节组MSCT灌注成像参数中的血容量、血流量、表面渗透系数高于良性结节组(P<0.05)。受试者工作特征曲线结果显示,MSCT灌注成像参数中的血容量、血流量、表面渗透系数单独及联合诊断SPN良恶性的曲线下面积(AUC)分别为0.823(95%CI:0.721~0.926)、0.855(95%CI:0.761~0.949)、0.850(95%CI:0.752~0.948)、0.963(95%CI:0.924~1.000),均有一定诊断价值,且当血容量、血流量、表面渗透系数分别为4.405 ml/100 g、51.325 ml/(min·100 g)、21.115 ml/(min·100 g)时,可获得最佳诊断效能,且联合诊断的价值较高。结论:MSCT灌注成像参数中血容量、血流量、表面渗透系数联合诊断SPN良恶性的价值较高,可为SPN良恶性的早期诊断与治疗提供有效依据。

肺通气/灌注显像在慢性血栓栓塞性肺动脉高压诊断和评估中的应用

慢性血栓栓塞性肺动脉高压是一种严重的肺血管疾病,其诊断和治疗过程极具挑战性。作为一种非侵入性检查技术,肺通气/灌注显像在慢性血栓栓塞性肺动脉高压的诊断、病情评估和治疗决策中发挥着关键作用。本文综合分析了肺通气/灌注显像在慢性血栓栓塞性肺动脉高压诊断和评估中的应用,探讨了其技术原理、优势以及未来技术发展的潜在方向。

基于EIT的不同体位下肺通气、肺灌注区域分布和通气/灌注匹配研究

目的:基于电阻抗断层成像(electrical impedance tomography,EIT)比较不同体位下的肺通气、肺灌注区域分布和通气/灌注(V/Q)匹配情况。方法:选取10只健康实验猪,采集其仰卧位、俯卧位、左侧卧位、右侧卧位下的EIT肺部通气和血流灌注数据。使用MATLAB R2022b,基于EIDORS v3.9进行EIT数据分析和图像重构,以最大像素值20%作为阈值确定具有通气和灌注的有效区域,并进行V/Q匹配区域计算。比较不同体位下V/Q匹配评价指标(匹配分数%、死腔分数%、分流分数%)及通气、灌注区域在不同感兴趣区域(ROI1、ROI2、ROI3、ROI4)内的分布。结果:实验动物在不同体位下的匹配分数%、死腔分数%、分流分数%差异无统计学意义(P>0.05)。在不同体位下,通气、灌注的区域分布发生改变,通气区域在ROI1、ROI2、ROI3分布差异有统计学意义(P<0.05),灌注区域在ROI1、ROI2分布差异有统计学意义(P<0.05)。在仰卧位和俯卧位下,通气、灌注区域分布呈现出与重力依赖区分布一致的现象,而在右侧卧位和左侧卧位下,通气、灌注区域分布则呈现出与重力依赖区分布相反的现象。结论:同一实验对象在不同体位下的全局V/Q匹配参数具有较好的检验一致性;测量体位的变化将导致肺重力依赖区的变化,进而影响局部肺通气和肺灌注区域的分布;EIT能够对体位改变导致的肺通气、肺灌注改变进行测定,明确体位变化对肺通气、肺灌注和V/Q匹配的影响。

双能量CT成像技术在肺血管疾病中的应用进展

双能量CT(DECT)应用两种能量、两套探测器,根据不同能量下物质衰减特性的差异进行定性及定量的数据采集。DECT具有高分辨率、易获得等优势,通过后处理技术,从形态学、功能学两方面获取疾病信息。近年来,DECT在肺血管疾病如肺栓塞、慢性血栓栓塞性肺动脉高压、动脉型肺动脉高压、肺静脉闭塞性疾病/肺毛细血管瘤等诊治中展现出优越的作用。现从DECT的技术原理及其在肺血管疾病中的应用进展做一综述。

肺通气/血流灌注显像与螺旋CT肺动脉造影诊断肺栓塞的实验研究

目的评价肺通气/血流灌注(pulmonary perfusion/ventilation,V/Q)显像与64层螺旋CT肺动脉造影(spiral computed tomographic pulmonary angiography,SCTPA)诊断肺栓塞的灵敏度和特异性。方法12只家兔按不同时间点分成4个实验组,每组3只,另设2只作为对照组。实验组经颈静脉插管注入海绵栓子制备急性肺栓塞模型,建模后分组行V/Q显像和SCTPA检查,随后处死实验动物行病理解剖,查找并记录肺动脉栓子位置及数目。对照组颈静脉插管注入生理盐水,于24 h和第3天处死。结果实验组家兔术中死亡1只,11只建模成功。家兔处死后共解剖动脉165支,发现栓子43个,栓塞肺动脉39支。V/Q显像共检出36处节段肺动脉栓塞,与病理解剖对照,假阳性7处、假阴性10处;SCTPA共诊断栓塞肺动脉32支,假阳性6支、假阴性13支。V/Q显像、SCTPA诊断实验家兔肺栓塞的灵敏度分别为74.4%、66.7%,特异性分别为94.4%和95.2%,准确性分别为89.7%和88.5%。结论肺通气/血流灌注显像诊断肺栓塞的灵敏度和准确性高于64层螺旋CT肺动脉造影,而特异性稍低,但无统计学差异。

CTPA与V/Q扫描诊断肺栓塞的比较研究

目的 以肺动脉造影为金标准 ,评价CT血管造影 (CTPA)和肺通气灌注扫描 (V/Q扫描 )对肺栓塞的临床诊断价值。方法 检索Cochrane图书馆、PubMed、Ovid数据库和中国期刊网中关于CTPA诊断肺栓塞的中英文文献 ,按照Cochrane协作网推荐的诊断试验的纳入标准筛选文献 ,提取纳入研究的特征信息。将入选研究和一项多中心的V/Q扫描的研究结果进行加权定量合并 ,计算汇总灵敏度和特异度及其 95 %可信区间 ,绘制汇总受试者工作特征曲线 (SROC) ,计算曲线下面积。评价两种检查方法与肺动脉造影结果的一致性。结果 8篇评价CTPA的文献符合纳入标准。CTPA的汇总灵敏度和特异度分别为 0 .86和 0 .90 ,V/Q扫描的汇总灵敏度和特异度为 0 .82和 0 .60。二者的SROC曲线下面积 (% )分别为 94.43和 81.90。CTPA与金标准肺动脉造影的诊断结果一致性较高。结论 CTPA诊断PE在准确性和确定性方面较V/Q扫描的价值高。鉴于CTPA的无创性及其与肺动脉造影结果的一致性 ,CTPA可作为肺动脉造影不能使用时的首选检查方法。

CT灌注成像在肺部肿物诊断及鉴别诊断中的应用研究

背景与目的:良、恶性肿瘤的血流供应与代谢在质、量上有着明显的差异,目前正在开发使用新的影像学技术来鉴别恶性、良性结节的血供情况,灌注成像技术是其中一种。本文采用多层螺旋CT灌注成像技术,定量评价肺内块状病灶的血流特点及其对良、恶性肿瘤进行鉴别诊断的价值。方法:52例初诊为肺部肿物的患者(37例恶性、7例良性、8例活动性炎性),行16排螺旋CT灌注扫描。利用功能软件包自动获取动、静脉、病灶的时间-密度曲线及病变的灌注参数,包括灌注量(perfusionvolume,PV)、血容量(bloodvolume,BV)、对比剂平均通过时间(meantransittimeMTT)、增强峰值(peakheight,PH)。结果:恶性、活动性炎性、良性病变PV值分为(27.63±15.06)ml·min-1·ml-1、(30.80±20.33)ml·min-1·ml-1、(11.81±3.74)ml·min-1·ml-1,PH值分别为(28.46±12.07)Hu、(32.15±15.89)Hu、(10.41±3.77)Hu,BV分别为(21.64±10.97)ml/100g、(28.38±14.55)ml/100g、(10.61±5.33)ml/100g,恶性及活动性炎性病变这3值均显著高于良性病变。恶性、活动性炎性、良性病变的MTT值分别为(28.39±21.66)s、(25.91±14.57)s、(29.86±13.57)s,三者差异没有统计学意义。恶性、活动性炎性病变间4个灌注参数均没有统计学差异。若以PV值>20ml·min-1·ml-1,且PH>15Hu作为鉴别恶性、良性病变(除外活动炎性病变)的阈值,其灵敏度、特异度、准确性分为91.9%、100%、84.1%。结论:多层螺旋CT灌注成像能定量评价肺部肿物血流模式,可用于无创性诊断和鉴别诊断肺部病变。

预测CT肺动脉造影联合肺通气灌注显像检查降低肺栓塞复发率的临床价值

目的:评估采用CT肺动脉造影(CTPA)联合肺通气灌注显像(V/Q)的检查方法指导肺栓塞抗凝治疗终点,对于减少肺栓塞复发率的临床价值。方法:159例经CTPA确诊的肺栓塞患者随机分为实验组80例及对照组79例,实验组经正规低分子肝素联合华法林抗凝治疗后采用CTPA联合V/Q显像检查的方法评估肺栓塞吸收情况,进一步指导抗凝治疗终点,评估停止抗凝治疗1年时肺栓塞的复发率,并与单纯采用CTPA指导抗凝治疗终点的对照组对比分析,评估两组复发率的差异。结果:实验组抗凝疗程为(5.90±1.80)个月,较对照组(3.57±1.09)个月显著延长(P<0.05);实验组停止抗凝治疗1年时肺栓塞的复发率为7.5%,较对照组复发率(22.8%)明显降低(P<0.05);但两组患者抗凝治疗期间的出血率(8.75%vs.3.80%)差异无显著性(P>0.05)。结论:采用CTPA联合V/Q显像检查的方法指导肺栓塞抗凝治疗终点,对于降低肺栓塞的复发率具有重要的临床价值。

呼气末正压通气对腹腔热灌注化疗患者呼吸力学及肺功能的影响

目的探讨不同呼气末正压通气对腹腔热灌注化疗患者呼吸力学及肺功能的影响。方法选择择期行腹膜癌热灌注化疗的患者90例,男55例,女35例,年龄40~70岁,ASAⅠ~Ⅲ级。随机分为三组,每组30例。A组为容量控制通气(VCV)组,VT10 ml/kg;B组为VCV+低PEEP组,VT6ml/kg,PEEP 5cm H_2O;C组为VCV+高PEEP组,VT6ml/kg,PEEP 10cm H_2O;术中调整RR维持PETCO2 35~45 mm Hg。于气管插管后5 min(T_1)、腹腔热灌注化疗开始前(T2)、化疗结束时(T_3)、气管拔管前(T4)记录气道峰压(Ppeak)、气道平台压(Pplat)和平均气道压(Pmean),计算动态肺顺应性(C_(dyn))。并取桡动脉血进行血气分析,计算氧合指数(OI)、呼吸指数(RI)、肺泡-动脉血氧分压差(A-aDO_2)及死腔率(VD/VT)。记录术后7d内肺部相关并发症情况。结果与A组比较,T_1~T_4时B、C组Ppeak、Pplat、A-aDO_2和RI明显降低,OI和VD/VT明显升高(P<0.05);T_2~T_4时B、C组Pmean明显降低,Cdyn和PaO_2明显升高(P<0.05)。与T_1比较,T_2~T_4时A组Ppeak、Pplat和Pmean明显升高,C_(dyn)明显降低(P<0.05);T_3时B组Ppeak和Pplat明显升高(P<0.05),T_2~T_4 Pmean明显升高(P<0.05),T3、T4时C_(dyn)明显降低(P<0.05);T_2~T_4时C组Ppeak、Pplat和Pmean明显升高(P<0.05),T_3、T_4时Cdyn明显降低(P<0.05)。与T0时比较,T2~T4时三组PaO_2和OI明显降低,A-aDO_2、RI和VD/VT明显升高(P<0.05)。术后7d内B、C组肺部感染、低氧血症和肺不张的发生率明显低于A组(P<0.05)。结论小潮气量(6ml/kg)联合PEEP(5cm H_2O)通气可以显著改善腹膜癌患者术中热灌注期间肺功能,降低围术期肺部并发症的发生风险。

SPECT/CT肺灌注显像与肺通气/灌注平面显像在肺栓塞诊断中的应用比较

目的分析单光子发射型计算机断层/低剂量平扫CT(SPECT/CT)肺灌注显像与肺通气/灌注(V/Q)平面显像在肺栓塞诊断中的应用。方法将2017年6月至2018年10月我院收治的120例疑似肺栓塞患者作为研究对象,所有患者均进行SPECT/CT肺灌注显像和V/Q平面显像检查,以临床最终诊断结果为准,评估SPECT/CT肺灌注显像和V/Q平面显像对肺栓塞的诊断效能。结果 120例患者中最终有100例诊断为肺栓塞,其中肺段病变247个,亚肺段病变285个。SPECT/CT肺灌注显像对肺栓塞诊断灵敏度、特异度、准确度、阳性预测值、阴性预测值分别为89.00%、90.00%、89.17%、97.80%、62.07%,均大于V/Q平面显像的81.00%、80.00%、80.83%、95.29%、45.71%。SPECT/CT肺灌注显像对肺栓塞肺段病变检出率87.04%与V/Q平面显像的82.19%无显著差异(P>0.05),对亚肺段病变检出率92.28%高于V/Q平面显像的85.96%(P<0.05)。结论 SPECT/CT肺灌注显像对肺栓塞的诊断效能优于V/Q平面显像,且可提高对亚肺段病变检出率。

MSCT灌注成像鉴别诊断肺结节良恶性:Meta分析

目的应用Meta分析方法评价MSCT灌注成像鉴别诊断肺结节良恶性的价值。方法检索Cochrane图书馆、Cochrane协作网、Pubmed、Web of science、中国知网及万方数据库中于2004年1月—2015年10月发表的有关CT灌注成像诊断肺结节的中英文文献,提取符合纳入标准的诊断试验数据。采用Meta disc 1.4分别汇总MSCT以不同灌注参数[血容量(BV)、表面通透性(PS)、BV+PS]诊断恶性肺结节的敏感度、特异度及95%可信区间(CI),拟合工作特征曲线(SROC)并计算曲线下面积(AUC)。结果共纳入文献18篇,肺结节1 221个,其中恶性结节780个,良性结节441个。依次以BV、PS、BV+PS作为灌注诊断指标进行分析,其汇总敏感度分别为0.91[95%CI(0.89,0.93)]、0.88[95%CI(0.85,0.90)]、0.91[95%CI(0.88,0.93)],汇总特异度分别为0.77[95%CI(0.73,0.81)]、0.83[95%CI(0.79,0.86)]、0.91[95%CI(0.87,0.94)];相应AUC分别为0.92、0.93、0.97。结论 MSCT以BV、PS作为灌注诊断参数对鉴别肺结节良恶性具有较高的敏感度及特异度,当二者结合时诊断效能更高,可作为鉴别诊断的标准化灌注指标。