Pérez Miguelsanz M J, Cabrera Parra W, Varela Moreiras G, Garaulet M
Departamento de Anatomía y Embriología humana I, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, España.
Nutr Hosp. 2010 Mar-Apr;25(2):207-23.
Fat mass is the most variable component in the human body, both when comparing several individuals and when considering changes in the same person throughout life. Obesity is characterized by an excess of body fat that affects health and well-being of individuals. Risk associated with excess body fat is due, in part, to location of fat rather than to total amount. Today is stated that causes and metabolic consequences of regional distribution of fat are of particular clinical importance. To identify a compartment of morbid adipose tissue and to be able to act on it is one of the main aims of the present research. In this review, we have revised the existing literature on location and characteristics of total body fat in human adult. We have focused on abdominal region, basing this review on the use of modern imaging techniques available nowadays, such as computerized tomography and magnetic resonance imaging, with their advantages and limitations. The purpose of this review is to assess whether it is possible to know the body composition and fat distribution on the basis of image methods. Computed tomography technique was first applied in studies of obesity, but today, due to the inconvenience of irradiating the patient, this technique is being replaced by magnetic resonance that, in addition to avoid radiation, provides images of extraordinary quality. Both methods allow to subdivide the classic general fat depots in others more specific. Subcutaneous fat depot can be superficial or deep, while visceral can be divided in mesenteric, omental or epiploic, retroperitoneal and perirrenal fat. In addition, these modern techniques of imaging permit to study muscular fat, considered by some authors as the new fat compartment. Muscular fat includes fat located between skeletal muscle fibers, called extramyocellular fat, as well as lipids located within skeletal muscle fibers (intramyocellular fat). Its importance lies not only in size, similar to visceral fat, but on its pathophysiological implications. Finally, techniques of image analysis have prove to be extremely useful in studying the location and extent of abdominal fat compartments, becoming reference to validate equations obtained from the so-called "indirect methods".
脂肪量是人体中最具变化性的组成部分，无论是在比较不同个体时，还是在考虑同一个人一生中的变化时。肥胖的特征是体内脂肪过多，这会影响个体的健康和幸福。与过多体脂相关的风险部分归因于脂肪的位置而非总量。如今人们认为，脂肪区域分布的原因和代谢后果具有特别重要的临床意义。识别病态脂肪组织的一个部分并能够对其采取行动是本研究的主要目标之一。在这篇综述中，我们回顾了关于成年人体全身脂肪的位置和特征的现有文献。我们将重点放在腹部区域，本次综述基于当今可用的现代成像技术，如计算机断层扫描和磁共振成像，以及它们的优缺点。本综述的目的是评估是否有可能基于图像方法了解身体成分和脂肪分布。计算机断层扫描技术最初应用于肥胖研究，但如今，由于对患者进行辐射带来不便，该技术正被磁共振成像所取代，磁共振成像除了避免辐射外，还能提供高质量的图像。这两种方法都可以将经典的一般脂肪库细分为更具体的脂肪库。皮下脂肪库可以是浅表的或深部的，而内脏脂肪可以分为肠系膜、网膜或腹膜脂肪、腹膜后和肾周脂肪。此外，这些现代成像技术还可以研究肌肉脂肪，一些作者认为肌肉脂肪是新的脂肪库。肌肉脂肪包括位于骨骼肌纤维之间的脂肪，称为细胞外脂肪，以及位于骨骼肌纤维内的脂质（细胞内脂肪）。其重要性不仅在于大小，类似于内脏脂肪，还在于其病理生理学意义。最后,图像分析技术已被证明在研究腹部脂肪库的位置和范围方面极其有用，成为验证从所谓“间接方法”获得的方程的参考标准。
