Pennati Francesca, Arrigoni Filippo, LoMauro Antonella, Gandossini Sandra, Russo Annamaria, D'Angelo Maria G, Aliverti Andrea
The Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Italy.
Scientific Institute, IRCCS E. Medea, Bosisio Parini, Italy.
J Magn Reson Imaging. 2020 Feb;51(2):461-471. doi: 10.1002/jmri.26864. Epub 2019 Jul 13.
Duchenne muscular dystrophy (DMD) is characterized by progressive weakness and wasting of skeletal, cardiac, and respiratory muscles, with consequent cardiopulmonary failure as the main cause of death. Reliable outcome measures able to demonstrate specific trends over disease progression are essential.
To investigate MRI as a noninvasive imaging modality to assess diaphragm impairment in DMD. In particular, we sought to correlate MRI measurement of diaphragm structure and function with pulmonary function tests and with the abdominal volumes (V ) measured by optoelectronic plethysmography, being an index of the action of the diaphragm.
Cross-sectional study.
Twenty-six DMD patients (17.9 ± 6.2 years) and 12 age-matched controls (17.8 ± 5.9 years).
FIELD STRENGTH/SEQUENCE: 3-Point gradient echo Dixon sequence at 3T.
Images were acquired in breath-hold at full-expiration (EXP) and full-inspiration (INSP). INSP and EXP lung volumes were segmented and the diaphragm surface was reconstructed as the bottom surface of the left and the right lung. The inspiratory and the expiratory diaphragm surfaces were aligned by a nonrigid iterative closest point algorithm. On MRI we measured: 1) craniocaudal diaphragmatic excursion; 2) diaphragm fatty infiltration.
Three-parameter sigmoid regression, one-way analysis of variance (ANOVA), Spearman's correlation.
In patients, diaphragm excursion decreased with age (r = 0.68, P < 0.0001) and fat fraction increased (r = 0.51, P = 0.0002). In healthy subjects, diaphragm excursion and fat fraction had no relationship with age. Diaphragm excursion decreased with decreasing FEV %pred (r = 0.78, P < 0.0001) and FVC %pred (r = 0.76, P < 0.0001) and correlated with V (r = 0.60, P = 0.0002). Fatty infiltration increased with decreasing FEV1 %pred (r = -0.88, P < 0.0001) and FVC %pred (r = -0.88, P < 0.0001).
The progressive structural and functional diaphragm impairment is highly related to pulmonary function tests and to V . The results suggest that MRI might represent a new and noninvasive tool for the functional and structural assessment of the diaphragm.
2 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2020;51:461-471.
杜氏肌营养不良症（DMD）的特征是骨骼肌、心肌和呼吸肌进行性无力和萎缩，最终因心肺功能衰竭成为主要死因。能够显示疾病进展过程中特定趋势的可靠结局指标至关重要。
研究磁共振成像（MRI）作为一种非侵入性成像方式，用于评估DMD患者的膈肌损伤情况。具体而言，我们试图将膈肌结构和功能的MRI测量结果与肺功能测试以及通过光电体积描记法测量的腹部容积（V）相关联，腹部容积是膈肌活动的一个指标。
横断面研究。
26例DMD患者（17.9±6.2岁）和12例年龄匹配的对照组（17.8±5.9岁）。
场强/序列：3T下的3点梯度回波狄克逊序列。
在屏气状态下于完全呼气（EXP）和完全吸气（INSP）时采集图像。对INSP和EXP时的肺容积进行分割，并将膈肌表面重建为左右肺的底面。通过非刚性迭代最近点算法对齐吸气和呼气时的膈肌表面。在MRI上我们测量：1）膈肌的头足向移动；2）膈肌脂肪浸润。
三参数S形回归、单因素方差分析（ANOVA）、斯皮尔曼相关性分析。
在患者中，膈肌移动随年龄下降（r = 0.68，P < 0.0001），脂肪分数增加（r = 0.51，P = 0.0002）。在健康受试者中，膈肌移动和脂肪分数与年龄无关。膈肌移动随预计第一秒用力呼气容积（FEV %pred）和预计用力肺活量（FVC %pred）的降低而下降（r = 0.78，P < 0.0001；r = 0.76，P < 0.0001），并与V相关（r = 0.60，P = 0.0002）。脂肪浸润随FEV1 %pred和FVC %pred的降低而增加（r = -0.88，P < 0.0001；r = -0.88，P < 0.0001）。
膈肌进行性的结构和功能损伤与肺功能测试及V密切相关。结果表明，MRI可能是一种用于膈肌功能和结构评估的新型非侵入性工具。
2 技术效能：5级 《磁共振成像杂志》2020年；51:461 - 471。
