Tan Fei, Eddy Rachel L, Diamond Vanessa M, Rayment Jonathan H, Larson Peder E Z
UC Berkeley-UCSF Graduate Program in Bioengineering, University of California, Berkeley, Berkeley, California, USA.
Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA.
NMR Biomed. 2025 Jun;38(6):e70033. doi: 10.1002/nbm.70033.
MRI can provide localized assessment of lung function for monitoring people with lung disease. Hyperpolarized Xe MRI directly images pulmonary gas distribution but requires specialized hardware. Conventional H MRI acquisitions can also provide functional maps using free-breathing approaches. The purpose of this study is to evaluate regional ventilation derived from 3D ultrashort echo-time (UTE) H MRI using Motion-Compensated Low-Rank constrained reconstruction (MoCoLoR), by comparing against Xe MRI and pulmonary function testing as reference-standard. The study is retrospective in design. The study included 57 participants (25.4 ± 15.8 years, 35 males and 22 females): 12 healthy volunteers, 20 pediatric, and 25 adult people with cystic fibrosis (CF) scanned between January 2022 and February 2023. Field strength/sequence: 3T; Xe: 2D multislice spoiled gradient-recalled sequence; UTE H: variable-density 3D radial sequence. K-means-based Xe ventilation defect percent (VDP), forced expiratory volume in 1 s (FEV), and lung clearance index (LCI) were evaluated against UTE H VDP from a modified k-means method. The correspondence of ventilation defect maps from Xe and UTE H was also evaluated. Statistical tests included the Pearson correlation coefficient (r) and t tests, with p < 0.05 considered significant. Xe and UTE H VDP were significantly correlated (r = 0.64, p = ). Bland-Altman analysis showed a bias of -0.05 (p = ) and limits of agreement of (0.07, -0.17). The Dice spatial accuracy of the UTE-based ventilation defect regions using Xe as reference was 0.64 ± 0.05. UTE H VDP was significantly correlated with FEV (r = -0.54, p = ) and LCI (r = 0.48, p = ) and was significantly different between healthy and CF participants (p = 0.017), although the correlations and differences were stronger for Xe VDP. UTE H VDP correlated with Xe VDP, FEV, and LCI, and demonstrated high, consistent Dice spatial accuracy against Xe VDP. UTE H VDP captured variations in lung ventilation and has the advantage that it can be widely implemented on any MR system for evaluation and monitoring of patients with lung disease.
磁共振成像（MRI）可为监测肺部疾病患者提供肺部功能的局部评估。超极化氙气MRI可直接成像肺部气体分布，但需要专门的硬件设备。传统的氢质子MRI采集也可采用自由呼吸方法提供功能图谱。本研究的目的是通过与氙气MRI和肺功能测试作为参考标准进行比较，评估使用运动补偿低秩约束重建（MoCoLoR）从三维超短回波时间（UTE）氢质子MRI得出的局部通气情况。该研究采用回顾性设计。研究纳入了57名参与者（年龄25.4±15.8岁，男性35名，女性22名）：12名健康志愿者、20名儿童以及25名成年囊性纤维化（CF）患者，于2022年1月至2023年2月期间进行扫描。场强/序列：3T；氙气：二维多层扰相梯度回波序列；UTE氢质子：可变密度三维径向序列。基于K均值的氙气通气缺陷百分比（VDP）、一秒用力呼气容积（FEV）和肺清除指数（LCI）与改良K均值法得出的UTE氢质子VDP进行评估比较。还评估了氙气和UTE氢质子通气缺陷图谱的对应性。统计检验包括Pearson相关系数（r）和t检验，p<0.05被认为具有统计学意义。氙气和UTE氢质子VDP显著相关（r = 0.64，p = ）。Bland-Altman分析显示偏差为-0.05（p = ），一致性界限为（0.07，-0.17）。以氙气为参考的基于UTE的通气缺陷区域的Dice空间准确性为0.64±0.05。UTE氢质子VDP与FEV（r = -0.54，p = ）和LCI（r = 0.48，p = ）显著相关，并且在健康参与者和CF参与者之间存在显著差异（p = 0.017），尽管氙气VDP的相关性和差异更强。UTE氢质子VDP与氙气VDP、FEV和LCI相关，并且相对于氙气VDP表现出高且一致的Dice空间准确性。UTE氢质子VDP捕捉到了肺通气的变化，并且具有可在任何磁共振系统上广泛实施以评估和监测肺部疾病患者的优势。
