Measurement of mean subcutaneous fat thickness: eight standardised ultrasound sites compared to 216 randomly selected sites

Abstract

Ultrasound (US) provides the most accurate technique for thickness measurements of subcutaneous adipose tissue (SAT) layers. This US method was recently standardised using eight sites to capture SAT patterning and allows distinguishing between fat and embedded fibrous structures. These eight sites chosen for fat patterning studies do not represent the mean SAT thickness measured all over the body that is necessary for determining subcutaneous fat mass. This was obtained by SAT measurements at 216 sites distributed randomly all over the body. Ten participants with BMI below 28.5kgm−2 and SAT means (from eight sites) ranging from 3 mm to 10 mm were selected. The means from eight sites overestimated the means obtained from 216 sites (i.e. 2160 US measurements in the ten participants); the calibration factor of 0.65 corrects this; standard deviation (SD) was 0.05, i.e. 8%. The SD of the calibration factor transforms linearly when estimating the error range of the whole body’s SAT volume (body surface area times the calibrated mean SAT thickness). The SAT masses ranged from 3.2 to 12.4 kg in this group. The standard deviations resulting from solely the calibration factor uncertainty were ±0.3 and ±1.0 kg, respectively. For these examples, the SAT percentages were 4.9(±0.4)% and 13.3(±1.0)%.

Relative Body Weight and Standardised Brightness-Mode Ultrasound Measurement of Subcutaneous Fat in Athletes: An International Multicentre Reliability Study, Under the Auspices of the IOC Medical Commission

“…Ultrasound images were evaluated interactively using an evaluation software (Rotosport, Austria; rotosport.at) for semiautomatic evaluations of SAT thicknesses. Sound speed was set to 1450 m s −1 for distance determination in fat [3,[18][19][20][21][22]. At each site, the software detects the SAT segments between the lower border of the skin and the upper border of the muscle fascia (for example, see Fig.…”

“…Diagnostic (brightness-mode) ultrasound has been used for fat measurement since 1965 [33,34], and many publications followed. At sufficiently high probe frequency (12)(13)(14)(15)(16)(17)(18), the thickness measurement accuracy is approximately 0.1-0.2 mm [3,6,35], provided that the appropriate speed of sound in the given tissue is used (1450 ms −1 in fat [18][19][20][21][22]). The high accuracy enables measuring the embedded fibrous structures, which amount to substantial percentages of the SAT (Fig.…”

“…This is an important feature of this US measurement technique [3][4][5][6][7] as adipose tissue is highly compressible, and this degree of compressibility varies from site to site and between individuals [3]. Factors influencing accuracy are analysed in the ESM and in various publications [3,6,22]. However, the technical accuracy limits for US are not the crucial point: the limitations are set by biological reasons including detection of furrowed borders and visco-elastic deformations of adipose tissue.…”

On the possibility of using temperature to aid in thyroid nodule investigation

“…As future studies, it is very important to properly evaluate the neck fat layer of the patient before any consideration of the feasibility of using Infrared Thermography exams for TN investigation. For instance, this can be done by US thickness measurements of subcutaneous adipose tissue layer in the same US exam used to nodule size evaluation 26 . Mathematical model.…”

Структурні Зміни Внутрішніх Органів Свійських Кота Та Собаки У Разі Ожиріння, Зумовленого Цукровим Діабетом

“…Подібно до тварин з аліментарним ожирінням у котів і собак у разі цукрового діабету з симптомом ожиріння реєстрували значний вміст жирової тканини, що могло змінювати якість ультрасонографічної картини. Внаслідок поглинання ультразвуку жировою тканиною жирові прошарки можуть впливати на розміри внутрішніх органів, що погіршує оцінку стану їх паренхіми [14]. Підшкірний жировий прошарок візуалізується як нерухома субстанція під час дихання тварини, на відміну від абдомінального жиру та інших органів черевної порожнини [15].…”