Hiroki Ikuma MD, Presenter: Nothing to Disclose

Takayuki Masui MD, Abstract Co-Author: Nothing to Disclose

Kimihiko Sato MD, Abstract Co-Author: Nothing to Disclose

Motoyuki Katayama MD, Abstract Co-Author: Nothing to Disclose

Hidekazu Seo MD, Abstract Co-Author: Nothing to Disclose

Akihiko Kutsuna MD, Abstract Co-Author: Nothing to Disclose

Kenji Asano, Abstract Co-Author: Nothing to Disclose

Haruyuki Fukuchi, Abstract Co-Author: Nothing to Disclose

Atsushi Nozaki, Abstract Co-Author: Employee, General Electric Company

Hasnine Akter Haque DSc, Abstract Co-Author: Nothing to Disclose

Megumi Ishii, Abstract Co-Author: Nothing to Disclose

Masayoshi Sugimura, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

The increase of intra-abdominal fat is regarded as a risk factor of metabolic abnormalities and fat area measured by CT is one of the criteria of metabolic abnormalities. The purpose of this study was to clarify correlation between MR and CT measurements for the quantitative assessment of abdominal fat.

A total of 33 volunteers (23 men and 10 women) underwent whole-abdomen MR and CT. MR imaging was performed two times with an interval of about a week. All MR examinations were performed in a 1.5T system (Signa HDe, GE). In phase image, opposed phase image, water image, and fat image were obtained by Multi-Echo with 2-Point Dixon Reconstruction for Decomposition of Aqua/Lipid (MEDAL) sequence (TR msec/TE msec, 7.3/2.3, 4.6; matrix, 256x224; acquisition time, 24seconds; section thickness, 5mm; no gap). All CT examinations were performed in a 64detector CT scanner (Light Speed VCT, GE). Imaging analysis was performed on a workstation (AW suite, GE) or pc. In one slice at the umbilical level, we measured visceral, subcutaneous fat area, and Visceral fat/ total abdominal fat (visceral and Subcutaneous fat) ratio. MR and CT measurements were made by two radiologists, respectively and interobserver variability was also evaluated. Correlation was evaluated with linear regression analysis.

Good correlation between MR and CT measurements was observed. Visceral fat area of 33 subjects were 57.3±30.0 (mean±standard deviation) cm2 measured by MR, and 54.1±29.9 cm2 by CT (r=0.980, p<0.0001). Subcutaneous fat area were 135.6±60.4 cm2 by MR, and 136.4±61.7 cm2 by CT (r=0.956, p<0.0001). Visceral fat/ total abdominal fat ratio were 0.305±0.100 by MR, and 0.291±0.093 by CT (r=0.923, p<0.0001). Correlation between visceral fat area measured by first and second MR was good (r=0.959, p<0.0001). Interobserver correlation of visceral fat area was also good (r=0.971, p<0.0001 by MR; r=0.993, p<0.0001 by CT).

Good correlation was observed between MR and CT measurements of visceral and subcutaneous fat area. CT measurement of abdominal fat can be replaced by MR without ionizing radiation exposure.

MR can provide reliable measurements of abdominal fat area without radiation exposure in stead of CT.

Ikuma, H, Masui, T, Sato, K, Katayama, M, Seo, H, Kutsuna, A, Asano, K, Fukuchi, H, Nozaki, A, Haque, H, Ishii, M, Sugimura, M, et al, , Estimation of Abdominal Fat: Comparison with MR and CT Measurements.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6014027.html