Objective: To evaluate skeletal muscle and adipose tissue areas on multi-detector computed tomography in patients over 18 years of age with acute illness.
Methods: A retrospective–prospective cross-sectional descriptive study was conducted on 170 patients aged over 18 years who underwent examination at Military Hospital 103 between June 2025 and May 2026 and presented with acute diseases. All patients underwent multidetector computed tomography (MDCT) of the abdomen, with or without intravenous contrast administration.
Adipose tissue and skeletal muscle areas were measured on axial CT images at the level of the third lumbar vertebra (L3) using Coreslicer software, based on internationally standardized Hounsfield unit thresholds.
Results: Patient age ranged from 22 to 89 years (mean 46.7 years), including 138 male and 32 female patients, with a mean BMI of 23,76 ± 3,20 kg/m². SAT, SATI, and TATI were statistically significantly higher in females compared to males (158.49 ± 50.93 and 106.02 ± 50.22 cm² p = 0.001; 65.62 ± 21.63 and 38.14 ± 17.88 cm² p < 0.001; 119.43 ± 31.75 and 88.28 ± 37.18 p < 0.001). Conversely, the VAT/SAT ratio was significantly higher in males (1.40 ± 0.54 vs 0.864 ± 0.27; p < 0.001), reflecting a predominance of visceral fat distribution in men. VAT, VATI, and TAT areas did not differ significantly between the two sexes (p > 0.05). Meanwhile, SMA and SMI muscle tissue were significantly higher in males compared to females (149.18 ± 27.28 and 101.69 ± 10.46 cm² p<0.001; 53.70 ± 8.91 and 42.09 ± 4.59; p = 0.001).
Conclusion: : Multi-detector computed tomography enables objective quantification of skeletal muscle and abdominal adipose tissue compartments at the L3 level. Men had higher muscle mass and VAT/SAT ratio, whereas women had higher subcutaneous and total abdominal adiposity – reflecting sex-specific fat distribution patterns in Vietnamese patients with acute illness.