Co-registered perfusion SPECT/CT: Utility for prediction of improved postoperative outcome in lung volume reduction surgery candidates

Purpose

To directly compare the capabilities of perfusion scan, SPECT, co-registered SPECT/CT, and quantitatively and qualitatively assessed MDCT (i.e. quantitative CT and qualitative CT) for predicting postoperative clinical outcome for lung volume reduction surgery (LVRS) candidates.

Materials and methods

Twenty-five consecutive candidates (19 men and six women, age range: 42-72 years) for LVRS underwent preoperative CT and perfusion scan with SPECT. Clinical outcome of LVRS for all subjects was also assessed by determining the difference between pre- and postoperative forced expiratory volume in 1 s (FEV₁) and 6-min walking distance (6MWD). All SPECT examinations were performed on a SPECT scanner, and co-registered to thin-section CT by using commercially available software. On planar imaging, SPECT and SPECT/CT, upper versus lower zone or lobe ratios (U/Ls) were calculated from regional uptakes between upper and lower lung fields in the operated lung. On quantitatively assessed CT, U/L for all subjects was assessed from regional functional lung volumes. On qualitatively assessed CT, planar imaging, SPECT and co-registered SPECT/CT, U/Ls were assessed with a 4-point visual scoring system. To compare capabilities of predicting clinical outcome, each U/L was statistically correlated with the corresponding clinical outcome.

Results

Significantly fair or moderate correlations were observed between quantitatively and qualitatively assessed U/Ls obtained with all four methods and clinical outcomes (−0.60 ≤ r ≤ −0.42, p < 0.05).

Conclusion

Co-registered perfusion SPECT/CT has better correlation with clinical outcome in LVRS candidates than do planar imaging, SPECT or qualitatively assessed CT, and is at least as valid as quantitatively assessed CT.     

Quantitative Computed Tomography of Pulmonary Emphysema and Ventricular Function in Chronic Obstructive Pulmonary Disease Patients with Pulmonary Hypertension

Objective

This study strived to evaluate the relationship between degree of pulmonary emphysema and cardiac ventricular function in chronic obstructive pulmonary disease (COPD) patients with pulmonary hypertension (PH) using electrocardiographic-gated multidetector computed tomography (CT).

Materials and Methods

Lung transplantation candidates with the diagnosis of COPD and PH were chosen for the study population, and a total of 15 patients were included. The extent of emphysema is defined as the percentage of voxels below -910 Hounsfield units in the lung windows in whole lung CT without intravenous contrast. Heart function parameters were measured by electrocardiographic-gated CT angiography. Linear regression analysis was conducted to examine the associations between percent emphysema and heart function indicators.

Results

Significant correlations were found between percent emphysema and right ventricular (RV) measurements, including RV end-diastolic volume (R² = 0.340, p = 0.023), RV stroke volume (R² = 0.406, p = 0.011), and RV cardiac output (R² = 0.382, p = 0.014); the correlations between percent emphysema and left ventricular function indicators were not observed.

Conclusion

The study revealed that percent emphysema is correlated with RV dysfunction among COPD patients with PH. Based on our findings, percent emphysema can be considered for use as an indicator to predict the severity of right ventricular dysfunction among COPD patients.     

CT of pulmonary emphysema - current status, challenges, and future directions

Pulmonary emphysema is characterized by irreversible destruction of lung parenchyma. Emphysema is a major contributor to chronic obstructive pulmonary disease (COPD), which by itself is a major cause of morbidity and mortality in the western world. Computed tomography (CT) is an established method for the in-vivo analysis of emphysema. This review first details the pathological basis of emphysema and shows how the subtypes of emphysema can be characterized by CT. The review then shows how CT is used to quantify emphysema, and describes the requirements and foundations for quantification to be accurate. Finally, the review discusses new challenges and their potential solution, notably focused on multi-detector-row CT, and emphasizes the open questions that future research on CT of pulmonary emphysema will have to address.     

慢性阻塞性肺气肿上呼吸道病变的CT观察

目的　分析慢性阻塞性肺气肿上呼吸道的变化。方法　对 4 0例确诊为慢性阻塞性肺气肿患者和同期 39例正常对照者行肺部螺旋CT扫描。测量以下指标并进行统计学分析 :(1)气管横截面积 (Ta) ;(2 )气管指数 (Ti) ,即气管的最大横径 (Tc)和最大矢径 (Ts)的比率 ;(3)左、右主支气管直径 (分别记为Bl和Br) ;(4 )左、右主支气管的分叉角度 (Ba) ;(5 )胸廓指数 (Thi) ;(6 )气体潴留指数 (Ati)。结果　除Ba外 ,气肿组与对照组上述指标的均值差异都有显著性意义 ,气肿组的Ti与Ati呈明显的负相关 (r =- 0 5 93,P <0 0 0 1) ,Ti与Thi呈明显的正相关 (r =0 5 37,P <0 0 1)。Ta与Ati(r =0 10 5 ,P >0 0 5 )和Ta与Ti(r =- 0 12 5 ,P >0 0 5 )均无明显的相关关系。结论　Ti减小是慢性阻塞性肺气肿气管的主要变化 ,而且这种改变与肺气体潴留和胸廓改变相关     

Endoscopic lung volume reduction coils for patients with severe emphysema—a single-centre retrospective analysis

 Open in a separate windowOBJECTIVESPatients with chronic obstructive pulmonary disease and lung emphysema may benefit from surgical or endoscopic lung volume reduction (ELVR). Previously reported outcomes of nitinol coil-based ELVR techniques have been ambiguous. The analysis was done to analyse outcomes of ELVR with nitinol coils in patients with severe pulmonary emphysema.METHODSFrom September 2013 to November 2014, our centre performed a total of 41 coil implantations on 29 patients with severe emphysema. Coils were bronchoscopically placed during general anaesthesia. Twelve out of 29 patients received staged contralateral treatments up to 112 days later to avoid bilateral pneumothorax. Lung function and 6-min walking distance were assessed 1 week prior, 1 week after as well as 6–12 months after the procedure. Patients were followed up to 48 months after ELVR and overall mortality was compared to a historic cohort.RESULTSWhile coil-based ELVR led to significant short-term improvement of vital capacity (VC, +0.14 ± 0.39 l, P = 0.032) and hyperinflation (Δ residual volume/total lung capacity −2.32% ± 6.24%, P = 0.022), no significant changes were observed in 6-min walking distance or forced expiratory volume in 1 s. Benefits were short-lived, with only 15.4% and 14.3% of patients showing sustained improvements in forced expiratory volume in 1 s or residual volume after 6 months. Adverse events included haemoptysis (40%) and pneumothorax (3.4%), major complications occurred in 6.9% of cases. Overall survival without lung transplant was 63.8% after 48 months following ELVR, differing insignificantly from what BODE indices of patients would have predicted as median 4-year survival (57%) at the time of ELVR treatment.CONCLUSIONSELVR with coils can achieve small and short-lived benefits in lung function at the cost of major complications in a highly morbid cohort. Treatment failed to improve 4-year overall survival. ELVR coils are not worthwhile the risk for most patients with severe emphysema.     

Subcutaneous emphysema of the lower extremity secondary to a perforated esophageal carcinoma

The psoas muscle is a potential pathway of disease from the mediastinum to the leg. We describe a case of subcutaneous emphysema of the lower extremity due to a perforated esophageal carcinoma in a 58-year-old man.     

Native lung complications after single lung transplantation for emphysema

We reviewed the impact of the presence of the native diseased contralateral lung on the outcome after single lung transplantation for emphysema. Twenty consecutive recipients of single lung transplants for emphysema were reviewed for complications related to the native lung. Five patients (25 %) suffered major complications arising in the native lung and resulting in serious morbidity and mortality. The timing of onset varied from 1 day to 43 months after transplantation. We conclude that the susceptibility of the native lung to complications such as those described in this report is an additional fact to be considered in choosing the ideal transplant procedure for patients with obstructive lung disease. Received: 2 July 1996 Received after revision: 15 October 1996 Accepted: 28 October 1996     

慢阻肺气肿患者肺通气功能的CT评价

目的探讨双源CT检查肺容积和肺密度与慢性阻塞性肺疾病肺气肿患者肺通气功能的相关性。方法选取2015年1月至2016年6月在河南中医药大学第一附属医院就诊的COPD肺气肿患者102例进行研究,抽取同期在我院健康体检者102例作为对照组,2组患者均在3天内接受双源CT和肺通气功能检测,记录患者全肺容积(V):Vin、Vex,肺容积差(Vin-Vex),肺容积比(Vex/Vin);平均肺密度(MLD):MLDin和MLDex,平均肺密度差(VD);肺总量(TLC)、残气量(RV)、用力肺活量(FVC)、RV/TLC和第1秒用力呼气量与用力肺活量百分比(FEV1/FVC)。结果 COPD肺气肿组患者TLC、RV、RV/TLC、Vex、Vin、Vex/Vin均较对照组显著升高(P均0.05),FVC、FEV1/FVC、MLDin、MLDex和MLDex-MLDin水平均较对照组显著降低(P均0.05)。Vin-Vex与RV/TLC、FVC呈显著负相关,与FEV1/FVC呈正相关;Vex/Vin与RV、RV/TLC、FVC呈显著正相关,与FEV1/FVC呈显著负相关;MLDexMLDin与TLC、RV、RV/TLC呈显著负相关,与FVC、FEV1/FVC呈显著正相关,差异均有统计学意义(P均0.05)。结论双源CT检测肺容积和肺密度与COPD肺气肿患者肺通气功能指标有较好相关性,具有较高临床价值。