Cornacchia Samantha, La Tegola Luciana, Maldera Arcangela, Pierpaoli Elena, Tupputi Umberto, Ricatti Giovanni, Eusebi Laura, Salerno Sergio, Guglielmi Giuseppe
Medical Physics Unit, Dimiccoli Hospital Barletta, Barletta, ASL Barletta-Andria-Trani, Italy.
Department of Clinical and Experimental Medicine, Foggia University School of Medicine, Foggia, Italy.
Quant Imaging Med Surg. 2020 Aug;10(8):1723-1738. doi: 10.21037/qims-19-1035.
Body composition assessment (BCA) represents a valid instrument to evaluate nutritional status through the quantification of lean and fat tissue, in healthy subjects and sick patients. According to the clinical indication, body composition (BC) can be assessed by different modalities. To better analyze radiation risks for patients involved, BCA procedures can be divided into two main groups: the first based on the use of ionizing radiation (IR), involving dual energy X-ray absorptiometry (DXA) and computed tomography (CT), and others based on non-ionizing radiation (NIR) [magnetic resonance imaging (MRI)]. Ultrasound (US) techniques using mechanical waves represent a separate group. The purpose of our study was to analyze publications about IR and NIR effects in order to make physicians aware about the risks for patients undergoing medical procedures to assess BCA providing to guide them towards choosing the most suitable method. To this end we reported the biological effects of IR and NIR and their associated risks, with a special regard to the excess risk of death from radio-induced cancer. Furthermore, we reported and compared doses obtained from different IR techniques, giving practical indications on the optimization process. We also summarized current recommendations and limits for techniques employing NIR and US. The authors conclude that IR imaging procedures carry relatively small individual risks that are usually justified by the medical need of patients, especially when the optimization principle is applied. As regards NIR imaging procedures, a few studies have been conducted on interactions between electromagnetic fields involved in MR exam and biological tissue. To date, no clear link exists between MRI or associated magnetic and pulsed radio frequency (RF) fields and subsequent health risks, whereas acute effects such as tissue burns and phosphenes are well-known; as regards the DNA damage and the capability of NIR to break chemical bonds, they are not yet robustly demonstrated. MRI is thus considered to be very safe for BCA as well US procedures.
身体成分评估（BCA）是一种通过量化健康受试者和患病患者的瘦组织和脂肪组织来评估营养状况的有效工具。根据临床指征，身体成分（BC）可通过不同方式进行评估。为了更好地分析相关患者的辐射风险，BCA程序可分为两大类：第一类基于电离辐射（IR）的使用，包括双能X线吸收法（DXA）和计算机断层扫描（CT），另一类基于非电离辐射（NIR）[磁共振成像（MRI）]。使用机械波的超声（US）技术则自成一类。我们研究的目的是分析关于IR和NIR影响的出版物，以使医生了解接受BCA评估医疗程序的患者所面临的风险，从而指导他们选择最合适的方法。为此，我们报告了IR和NIR的生物学效应及其相关风险，特别关注辐射诱发癌症导致的额外死亡风险。此外，我们报告并比较了不同IR技术获得的剂量，给出了优化过程的实际建议。我们还总结了当前使用NIR和US技术的建议和限制。作者得出结论，IR成像程序带来的个体风险相对较小，通常因患者的医疗需求而合理，特别是在应用优化原则时。至于NIR成像程序，关于MR检查中涉及的电磁场与生物组织之间的相互作用已开展了一些研究。迄今为止，MRI或相关的磁场和脉冲射频（RF）场与后续健康风险之间尚无明确联系，而诸如组织灼伤和光幻视等急性效应是众所周知的；至于DNA损伤以及NIR破坏化学键的能力，尚未得到有力证实。因此，MRI以及US程序在BCA中被认为是非常安全的。
