Mohammad Munir Izzati, Leong Sook Sam, Mahfudz Anis Shafina, Ch'ng Li Shyan, Wong Jeannie Hsiu Ding, Vijayananthan Anushya, Wong Chee Kuan
Centre for Medical Imaging Studies, Universiti Teknologi Mara, Puncak Alam, Selangor, Malaysia.
Centre for Medical Imaging Studies, Universiti Teknologi Mara, Puncak Alam, Selangor, Malaysia.
Ultrasound Med Biol. 2025 Sep;51(9):1547-1554. doi: 10.1016/j.ultrasmedbio.2025.05.027. Epub 2025 Jun 25.
Changes in diaphragmatic stiffness are associated with pathological conditions, including severe pneumonia, and the application of shear wave elastography (SWE) in evaluating diaphragmatic stiffness has been studied. This study investigates confounding factors in diaphragmatic SWE to facilitate the development of a standard protocol that may be used in a clinical setting.
A total of 84 healthy volunteers were subjected to SWE to determine the shear wave velocity (SWV) and coefficient of variation (CV) of their diaphragms. The effects of transducer frequency, respiration, scanning sides, body positioning and region of interest (ROI) were investigated. 20 volunteers from the recruited volunteers were re-scanned by a second observer.
No significant differences were observed in median SWV for transducer frequencies, scanning sides and ROI locations. For respiration, median SWV was higher during inspiration than during expiration (p < 0.001). There was also a significant difference in diaphragm CV between the former and the latter (p = 0.038). The median SWV for body position was significantly higher when sitting compared with lying in the supine position (p < 0.001). Regarding CVs, these were lower for the L10-2 transducer, inspiration, left side, supine position, and at inferior ROI locations, although most were not significant except for respiration. Inter-observer reliability appeared to have a low error rate, as indicated by the intra-class correlation coefficient of 0.911.
We recommend a protocol that uses a higher frequency L18-5 transducer. Imaging should be taken in the supine position during inspiration at the right middle hemi diaphragm area.
膈肌僵硬度的变化与包括重症肺炎在内的病理状况相关，且已对剪切波弹性成像（SWE）在评估膈肌僵硬度方面的应用进行了研究。本研究调查膈肌SWE中的混杂因素，以促进可用于临床环境的标准方案的制定。
共84名健康志愿者接受SWE检查，以确定其膈肌的剪切波速度（SWV）和变异系数（CV）。研究了换能器频率、呼吸、扫描侧、身体体位和感兴趣区域（ROI）的影响。从招募的志愿者中选取20名由第二名观察者重新扫描。
在换能器频率、扫描侧和ROI位置方面，中位SWV未观察到显著差异。对于呼吸，吸气时的中位SWV高于呼气时（p < 0.001）。两者之间的膈肌CV也存在显著差异（p = 0.038）。与仰卧位相比，坐位时身体体位的中位SWV显著更高（p < 0.001）。关于CV，L10 - 2换能器、吸气、左侧、仰卧位以及ROI下方位置的CV较低，尽管除呼吸外大多数差异不显著。组内相关系数为0.911，表明观察者间可靠性的错误率较低。
我们推荐使用较高频率的L18 - 5换能器的方案。成像应在吸气时于仰卧位在右中半膈肌区域进行。
