Chowdhury B, Sjöström L, Alpsten M, Kostanty J, Kvist H, Löfgren R
Department of Medicine, University of Göteborg, Sahlgrenska Hospital, Sweden.
Int J Obes Relat Metab Disord. 1994 Apr;18(4):219-34.
The objective of this study was to develop a body composition method based on computerized tomography (CT) which would make it possible to divide the body into multiple compartments at the tissue and organ level. Eight healthy males (21-42 years old) with BMIs ranging from 18.6 to 25.3 kg/m2 were used for the methodological development. Areas of tissues, organs and air/gas were measured in 28 cross-sectional scans having defined and identical positions in all examined subjects. The area determinations were performed with the following attenuation intervals (given in Hounsfield units, HU): air, gas and lungs: -1001 to -191 HU; adipose tissue (AT): -190 to -30 HU; all other soft tissues and organs: -29 to +151 HU; skeleton: 152 to 2500 HU. Various tissue and organ areas in the -29 to +151 HU interval were obtained by means of cursor circumscriptions, while area determinations in other intervals were based on the number of pixels fulfilling given attenuation criteria. Volumes of tissues, organs and gas were obtained from corresponding areas and the distances between the scans. The body was divided into 12 main volumes of tissues, organs and gas that could be further subdivided by region. The main volumes observed (in litres; mean +/- s.d.) were: skeleton (subdivisible into dense skeleton, red and yellow bone marrow): 8.7 +/- 0.9; skeletal muscle: 31.9 +/- 5.1; visceral AT (subdivisible into intra- and retroperitoneal, cardiac, other thoracic AT): 3.0 +/- 1.7; intra- and retroperitoneal organs other than AT: 4.6 +/- 0.8; gastrointestinal gas: 0.25 +/- 0.09; heart: 0.61 +/- 0.12; lungs and bronchial air: 5.1 +/- 1.1; other thoracic organs: 0.32 +/- 0.08; mammary glands: 0.001 +/- 0.004; CNS (subdivisible into brain and contents of spinal channel): 1.6 +/- 0.15; air in sinuses and trachea: 0.19 +/- 0.05; subcutaneous AT: 11.6 +/- 2.8; skin: 2.4 +/- 0.39. Precision errors as determined from double analyses of different tissue volumes ranged from 0.01 to 0.3 litres. For validation purposes, CT-estimated organ weights were obtained by multiplying organ volumes by their assumed densities. The sums of all organ weights were then compared with the measured body weights. The error calculated from the individual differences between these weights was 0.6 kg (0.85%). The multicompartmentation technique described has a high validity and reproducibility and is applicable over a wide range of medical fields which require body composition measurements at the tissue and organ level.
本研究的目的是开发一种基于计算机断层扫描（CT）的身体成分分析方法，该方法能够在组织和器官层面将身体划分为多个部分。选取了8名健康男性（年龄在21至42岁之间，体重指数为18.6至25.3kg/m²）用于方法开发。在所有受试对象中，于28个具有明确且相同位置的横断面扫描中测量组织、器官以及空气/气体的面积。面积测定采用以下衰减区间（以亨氏单位，HU表示）：空气、气体和肺：-1001至-191HU；脂肪组织（AT）：-190至-30HU；所有其他软组织和器官：-29至+151HU；骨骼：152至2500HU。在-29至+151HU区间内，通过光标划定获取各种组织和器官的面积，而其他区间的面积测定则基于满足给定衰减标准的像素数量。组织、器官和气体的体积通过相应面积以及扫描之间的距离得出。身体被划分为12个主要的组织、器官和气体体积部分，这些部分可进一步按区域细分。观察到的主要体积（单位：升；均值±标准差）如下：骨骼（可细分为致密骨骼、红骨髓和黄骨髓）：8.7±0.9；骨骼肌：31.9±5.1；内脏脂肪组织（可细分为腹膜内和腹膜后、心脏、其他胸腔脂肪组织）：3.0±1.7；除脂肪组织外的腹膜内和腹膜后器官：4.6±0.8；胃肠道气体：0.25±0.09；心脏：0.61±0.12；肺和支气管空气：5.1±±1.1；其他胸腔器官：0.32±0.08；乳腺：0.001±0.004；中枢神经系统（可细分为脑和脊髓腔内容物）：1.6±0.15；鼻窦和气管内空气：0.19±0.05；皮下脂肪组织：11.6±2.8；皮肤：2.4±0.39。通过对不同组织体积进行双份分析确定的精确误差范围为0.01至0.3升。为进行验证，通过将器官体积乘以假定密度来获得CT估算的器官重量。然后将所有器官重量的总和与测量的体重进行比较。由这些重量之间的个体差异计算出的误差为0.6kg（0.85%）。所描述的多部分划分技术具有高度的有效性和可重复性，适用于广泛需要在组织和器官层面进行身体成分测量的医学领域。
