Dynamic Oxygen-Enhanced MR Imaging. Development for Clinical Stage Classification of COPD and TherapeuticEffect Evaluation

本研究的目的是建立动态氧增强MR成像用于COPD患者的临床分期和疗效评价，研究对象包括非吸烟者和本机构的COPD患者。所有患者均进行COPD的ATS/ERS分级或GOLD分级。所有受试者均前瞻性接受肺功能检查、动态氧增强MR成像、灌注扫描和/或CT检查。使用我们的专有软件计算动态氧增强MRI上的平均相对增强比和洗入时间以及定量CT上的基于CT的功能肺体积。比较动态氧增强MRI和定量CT对肺功能丧失的评估效果，两种指标均与肺功能参数相关。比较4个临床分期组的平均相对强化率和基于CT的功能肺体积，以确定两种方法对临床分期的有效性。此外，本研究还纳入了氧增强MRI评估的多中心研究，并在COPD临床分期中比较了氧增强能力和基于CP的功能肺容积。两项指标与肺功能参数的相关性均非常显著（P<0.0001）。肺功能参数和平均相对增强率在四组间差异有统计学意义（P<0.05）。“无COPD的吸烟者”和“轻度COPD”的基于CT的功能肺体积与“中度COPD”和“重度或极重度COPD”的功能肺体积有显著差异（p<0.05）。结论：动态氧增强MRI和定量CT对吸烟相关COPD的肺功能评估和临床分期是有效的。

The purpose of this study was to develop the dynamic oxygen-enhanced MR imaging for clinical stage classification and therapeutic effect evaluation in COPD subjects.Non-smoking subjects and COPD patients in our institution were included in this study. All patients were assessed ATS/ERS classification of COPD or GOLD classifications. All subjects were prospectively underwent pulmonary function test, dynamic oxygen-enhanced MR imaging, perfusion scan and/ or CT. Mean relative enhancement ratio and wash-in time on dynamic oxygen-enhanced MRI and CT-base functional lung volume on quantitative CT were computationally calculated by using our proprietary software. To compare the efficacy of dynamic oxygen-enhanced MRI and quantitative CT for pulmonary functional loss assessment, both indexes were correlated with pulmonary functional parameters. To determine the efficacy of two methods for clinical stage classification, the four clinical stage groups' mean relative enhancement ratio and CT-based functional lung volume were statistically compared. In addition, this study was also included the multicenter study for assessment of oxygen-enhanced MRI, and compared capability of oxygen-enhancement and CP-based functional lung volume in clinical stages in COPD. Correlations of both indexes with pulmonary functional parameters were significant (p<0.0001). Pulmonary functional parameters and mean relative enhancement ratio for the four clinical groups showed significant differences (p<0.05). CT-based functional lung volumes of ‘Smokers without COPD' and ‘Mild COPD' were significantly different from those for 'Moderate COPD' and 'Severe or Very Severe COPD' (p<0.05). In conclusion, dynamic oxygen-enhanced MRI is effective for pulmonary functional loss assessment and clinical stage classification of smoking-related COPD as well as quantitative CT.