Ultrasonographical Diagnosis of Fatty Liver: Significance of the Liver-Kidney Contrast

Abstract

In order to investigate the reliability of ultrasonography in the diagnosis of fatty liver, retrospective evaluation was made of abdominal echograms in 45 patients with various diffuse liver diseases who underwent liver biopsy within 2 weeks after the ultrasound study. Instead of the well-recognized but subjective diagnostic criterion, i.e. the bright liver pattern, liver-kidney contrast is proposed as a new criterion. The liver-kidney contrast is based on the brightness of the liver in comparison to the renal parenchyma where fatty change seldom occurs. Combination of this liver-kidney contrast with two other well-known ultrasonographical findings of fatty liver, vascular blurring and deep attenuation, enables us to grade fatty change semiquantitatively. When fatty change of over 30% in the hepatic lobule was adopted as the definition of fatty liver, the satisfaction of both liver-kidney contrast and vascular blurring presented an ultrasound diagnostic criterion for fatty liver, with sensitivity of 83%, specificity of 100%, and an accuracy of 96%.

Fatty liver incidence and predictive variables

“…23 Ultrasonography is a sensitive and reasonably accurate diagnostic tool for assessing fat infiltration of the liver. Others have found 83% sensitivity and 100% specificity in comparison with histology, and 100% sensitivity and 56% specificity in comparison with CT. 23,24 In this study, a second radiologist blindly reviewed 40 films originally classified as fatty liver and 80 films from age-and sex-matched persons that were not so classified. The positive agreement rate by the second rater was 80% and the negative agreement rate was 95%, yielding a kappa coefficient of agreement of 0.77.…”

The incidence rate of hepatosteatose in virus carriers with inactive Hepatitis B

“…Since histological workup is difficult to perform in order to make a diagnose, USG scanning can be used as the most practical and invasive method [10]. USG yields with a sensitivity of 83 % and a specificity of 100% [11]. In this study, the frequency of hepatosteatosis in inactive HBV carriers was found 68.7% which suggested an increased rate compared to the general population.…”

A case of idiopathic fatty liver detectable only by ultrasonography.

“…According to our ultrasound diagnostic criteria for the fatty liver (Yajima et al 1982b), a fatty change of about 50% of the area in the hepatic lobule was suspected (Fig. 1).…”

“…Moreover the influence of the thick abdominal wall must be taken into consideration and the advanced fibrosis of liver has been said to show bright liver pattern, too (Joseph et al 1979; Dewbury and Clark 1979). In the previous paper (Yajima et al 1982b), we proposed "liver-kidney contrast" which was defined as the relative brightness of the liver to the renal parenchyma where fatty change seldom occurs. In addition, it was also reported that combination of this liver-kidney contrast with two other well-known ultrasound findings of fatty liver, vascular blurring and deep attenuation, enabled us to grade fatty change semiquantitativel.y.…”

“…We have recently reported our experience on the significance of "liver-kidney contrast" in the ultrasound diagnosis of fatty liver (Yajima et al 1982b). Thereafter many patients with fatty liver were encountered in the ultrasound mass screening of the liver, biliary tract and pancreas (Ohta et al 1982).…”