CT를 이용한 복부지방 측정

Measurement of Abdominal Fat Using CT

Purpose The number of obesity patients, as well as interest towards them is increasing rapidly due to improvements in living standards and changes to dietary habits in life. In exanumng the relationship between obesity and related diseases, focus is being drawn to the distribution of body fat, rather than the measurement of total body fat. For such measurements, CT is emerging as a new and alternative method to previous measuring methods. This paper purposes to set a measurement standard to ensure objective and consistent results. Materials & Methods Among 100 patients whose abdominal obesity was measured using CT in our hospital from january 2004 to december 2005, 20 patients were selected to set the range for fat content. To do this, 10*10 pixel CT number of the patients were examined. Also, all 100 patients were observed to see if the distribution of subcutaneous and visceral fat shows maximum value at the umbilical level. Results In an axial image of 20 patients whose abdominal obesity was measured, all CT Numbers ranged between -140 to -80 when 10*10 pixel was randomly placed on any location within subcutaneous and visceral fat area, which are anatomically fatty areas. During follow-up, L2~3, L3~4, L4~5 and S-I joints were examined based on the spine to scan the identical area. In this examination, umbilical level was visualized in the center of the four areas scanned. Observing each cross-section, the distribution of visceral fat, which is deeply related to abnormal metabolism, had the maximum value at the umbilical level for only 45 patients out of 100. Among these 45 patients, the maximum value of subcutaneous and visceral fat matched in 23 patients, while they differed in the remaining 22 patients. Conclusion Although there are many methods to measure body fat, only CT can objectively numerate fat in each area of the body. Thus, the range of CT No. must be preset to ensure accurate measurement. Also, measurement should be made for subcutaneous and visceral fat not only at the umbilical level, but also at levels above and below the umbilical level to assess abdominal obesity.