From the Departments of Radiology (S.J.C., N.D.S.) and Anaesthetics (J.C.), Hammersmith Hospital, Imperial College Healthcare National Health Service (NHS) Trust, Du Cane Road, London W12 0HS, England; Department of Radiology, Guy's and St Thomas' NHS Foundation Trust, London, England (L.C.J.); Department of Imaging, North Bristol NHS Trust, Bristol, England (A.E.); Department of Bariatric Surgery, St Mary's Hospital, Imperial College Healthcare NHS Trust, London, England (A.R.A.); and Interstitial Lung Disease Unit, the Royal Brompton and Harefield NHS Foundation Trust, London, England (A.U.W.).
Radiology. 2020 Mar;294(3):669-675. doi: 10.1148/radiol.2020191060. Epub 2020 Jan 28.
Background There is significant pulmonary functional deficit related to obesity, but no prospective CT studies have evaluated the effects of obesity on the lungs and trachea. Purpose To evaluate lung parenchymal and tracheal CT morphology before and 6 months after bariatric surgery, with functional and symptomatic correlation. Materials and Methods A prospective longitudinal study of 51 consecutive individuals referred for bariatric surgery was performed (from November 2011 to November 2013). All individuals had undergone limited (three-location) inspiratory and end-expiratory thoracic CT before and after surgery, with concurrent pulmonary function testing, body mass index calculation, and modified Medical Research Council (mMRC) dyspnea scale and Epworth scoring. Two thoracic radiologists scored the CT extent of mosaic attenuation, end-expiratory air trapping, and tracheal shape. The inspiratory and end-expiratory cross-sectional areas of the trachea were measured. The paired test or Wilcoxon signed-rank test was used for pre- and postsurgical comparisons. Spearman correlation and logistic regression were used to evaluate correlations between CT findings and functional and symptom indexes. Results A total of 51 participants (mean age, 52 years ± 8 [standard deviation]; 20 men) were evaluated. Before surgery, air trapping extent correlated most strongly with decreased total lung capacity (Spearman rank correlation coefficient [] = -0.40, = .004). After surgery, there were decreases in percentage mosaic attenuation (0% [interquartile range {IQR}: 0%-2.5%] vs 0% [IQR: 0%-0%], < .001), air trapping (9.6% [IQR: 5.8%-15.8%] vs 2.5% [IQR: 0%-6.7%], < .001), and tracheal collapse (201 mm [IQR: 181-239 mm] vs 229 mm [186-284 mm], < .001). After surgery, mMRC dyspnea score change correlated positively with air trapping extent change ( = 0.46, = .001) and end-expiratory tracheal shape change ( = 0.40, = .01). At multivariable analysis, air trapping was the main determinant for decreased dyspnea after surgery (odds ratio, 1.2; 95% confidence interval: 1.1, 1.2; = .03). Conclusion Dyspnea improved in obese participants after weight reduction, which correlated with less tracheal collapse and air trapping at end-expiration chest CT. © RSNA, 2020
背景 肥胖与显著的肺功能缺陷相关，但尚无前瞻性 CT 研究评估肥胖对肺部和气管的影响。
目的 评估肥胖患者在减重手术后肺实质和气管的 CT 形态，同时进行功能和症状相关性分析。
材料与方法 对 51 例连续患者进行前瞻性纵向研究，这些患者因减重手术而转诊（2011 年 11 月至 2013 年 11 月）。所有患者均在术前和术后进行了有限的（三个部位）吸气和呼气胸部 CT 检查，同时进行了肺功能测试、体重指数计算以及改良的医学研究委员会（mMRC）呼吸困难量表和 Epworth 评分。两位胸部放射科医生对马赛克衰减、呼气末空气滞留和气管形状的 CT 程度进行了评分。测量气管的吸气和呼气时的横截面积。采用配对 t 检验或 Wilcoxon 符号秩检验比较手术前后的结果。采用 Spearman 相关和逻辑回归评估 CT 结果与功能和症状指标之间的相关性。
结果 共评估了 51 例参与者（平均年龄，52 岁±8[标准差]；20 例男性）。术前，空气滞留程度与肺活量降低的相关性最强（Spearman 秩相关系数[]=-0.40， =.004）。术后，马赛克衰减百分比下降（0%[四分位距{IQR}：0%-2.5%]比 0%[IQR：0%-0%]， <.001），空气滞留（9.6%[IQR：5.8%-15.8%]比 2.5%[IQR：0%-6.7%]， <.001）和气管塌陷（201 mm[IQR：181-239 mm]比 229 mm[186-284 mm]， <.001）减少。术后，mMRC 呼吸困难评分的变化与空气滞留程度的变化呈正相关（ = 0.46， =.001），与呼气末气管形态的变化也呈正相关（ = 0.40， =.01）。多变量分析显示，空气滞留是术后呼吸困难减轻的主要决定因素（比值比，1.2；95%置信区间：1.1，1.2； =.03）。
结论 肥胖患者减重后呼吸困难改善，与呼气末胸部 CT 显示的气管塌陷和空气滞留减少相关。
