Body Electrical Loss Analysis (BELA) – An Electromagnetic Method for the Assessment of Abdominal Visceral Fat Accumulation

Abstract

A new electromagnetic measurement method for the direct assessment of abdominal visceral adiposity is presented. The method relies on the measurement of the electrical losses arising from the subject standing in a tuned radio frequency coil excited into resonance. The coil is positioned so that it surrounds an individual at the abdomen. The conductive tissue (muscle) loads the coil more being lossier than the low conductive fatty tissue. The idea here is that, measuring the losses at multiple frequencies, the fat distribution of the subject could be assessed by weighting outer structural components as the frequency increases. The coil voltage was used as an indication of the loss changes. The method was tested by phantom measurements and, for a demonstration, in a one-volunteer measurement. Phantom A had saline in the middle of its volume and fat in the outer shell volume while phantom B had the reversed conductivity distribution. The measured coil-loading rates as a function of frequency were 0.14 mV/kHz and 0.41 mV/kHz for phantoms A and B, respectively. This result suggests that the loading rate can be a potential index for body composition analysis, which should be applicable in the assessment of visceral fat accumulation, so that the higher rates are an indication of a larger amount of visceral fat. In the one-volunteer measurement, the loading rate of 0.64±0.04 mV/kHz was observed. The 1.5-T magnetic resonance imaging showed that visceral and subcutaneous fat areas in this volunteer were 112.1 cm² and 269.4 cm², respectively, at the umbilicus level.