Center for Pulmonary Imaging Research, Pulmonary Medicine and Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.
POLARIS, Imaging Sciences, Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, Sheffield, UK.
Magn Reson Med. 2023 Dec;90(6):2420-2431. doi: 10.1002/mrm.29808. Epub 2023 Aug 1.
The underlying functional and microstructural lung disease in neonates who are born preterm (bronchopulmonary dysplasia, BPD) remains poorly characterized. Moreover, there is a lack of suitable techniques to reliably assess lung function in this population. Here, we report our preliminary experience with hyperpolarized Xe MRI in neonates with BPD.
Neonatal intensive care patients with established BPD were recruited (N = 9) and imaged at a corrected gestational age of median:40.7 (range:37.1, 44.4) wk using a 1.5T neonatal scanner. 2D Xe ventilation and diffusion-weighted images and dissolved phase spectroscopy were acquired, alongside H 3D radial UTE. Xe images were acquired during a series of short apneic breath-holds (˜3 s). H UTE images were acquired during tidal breathing. Ventilation defects were manually identified and qualitatively compared to lung structures on UTE. ADCs were calculated on a voxel-wise basis. The signal ratio of the Xe red blood cell (RBC) and tissue membrane (M) resonances from spectroscopy was determined.
Spiral-based Xe ventilation imaging showed good image quality and sufficient sensitivity to detect mild ventilation abnormalities in patients with BPD. Xe ADC values were elevated above that expected given healthy data in older children and adults (median:0.046 [range:0.041, 0.064] cm s ); the highest value obtained from an extremely pre-term patient. Xe spectroscopy revealed a low RBC/M ratio (0.14 [0.06, 0.21]).
We have demonstrated initial feasibility of Xe lung MRI in neonates. With further data, the technique may help guide management of infant lung diseases in the neonatal period and beyond.
早产儿（支气管肺发育不良，BPD）出生后肺部潜在的功能和微观结构疾病仍未得到充分描述。此外，缺乏可靠评估该人群肺功能的合适技术。在此，我们报告了我们在患有 BPD 的新生儿中使用超极化 Xe MRI 的初步经验。
招募了患有已确诊 BPD 的新生儿重症监护病房患者（N=9），并在中位校正胎龄：40.7（范围：37.1，44.4）wk 时使用 1.5T 新生儿扫描仪进行成像。采集了二维 Xe 通气和扩散加权图像以及溶解相光谱，以及 H 3D 径向 UTE。Xe 图像是在一系列短暂的窒息呼吸暂停期间采集的（约 3 s）。H UTE 图像是在潮式呼吸期间采集的。手动识别通气缺陷，并与 UTE 上的肺结构进行定性比较。在体素基础上计算 ADC。从光谱确定 Xe 红细胞（RBC）和组织膜（M）共振的信号比。
基于螺旋的 Xe 通气成像显示出良好的图像质量和足够的灵敏度，可检测患有 BPD 的患者的轻度通气异常。Xe ADC 值高于预期的健康儿童和成人的数据（中位数：0.046 [范围：0.041，0.064] cm s ）；从一个非常早产的患者中获得的最高值。Xe 光谱显示 RBC/M 比值低（0.14 [0.06，0.21]）。
我们已经证明了 Xe 肺部 MRI 在新生儿中的初步可行性。随着更多的数据，该技术可能有助于指导新生儿期和以后婴儿肺部疾病的管理。
