Correlation of fatty liver and abdominal fat distribution using a simple fat computed tomography protocol

AIM: To evaluate the relationship between hepatic fat infiltration and abdominal fat volume by using computed tomography (CT). METHODS: Three hundred and six patients who visited our obesity clinic between November 2007 and April 2008 underwent fat protocol CT scans. The age range of the patients was 19 to 79 years and the mean age was 49 years. The male to female ratio was 116:190. Liver and spleen attenuation measurements were taken with three regions of interests (ROIs) from the liver and two ROIs from the spleen. Hepatic attenuation indices (HAIs) were measured as follows: (1) hepatic parenchymal attenuation (CT_LP); (2) liver to spleen attenuation ratio (LS ratio); and (3) difference between hepatic and splenic attenuation (LS_dif). Abdominal fat volume was measured using a 3 mm slice CT scan starting at the level of the umbilicus and was automatically calculated by a workstation. Abdominal fat was classified into total fat (TF), visceral fat (VF), and subcutaneous fat (SF). We used a bivariate correlation method to assess the relationship between the three HAIs and TF, VF, and SF. RESULTS: There were significant negative correlations between CT_LP, LS ratio, and LS_dif with TF, VF, and SF, respectively. The CT_LP showed a strong negative correlation with TF and VF (r = -0.415 and -0.434, respectively, P < 0.001). The correlation between CTLP and SF was less significant (r = -0.313, P < 0.001). CONCLUSION: Fatty infiltration of the liver was correlated with amount of abdominal fat and VF was more strongly associated with fatty liver than SF.