Liver size evaluated by ultrasound: ROC curves for hepatitis and alcoholism.

A previous study determined the normal values and upper limits of liver size, as measured by the longitudinal and sagittal diameters in the midclavicular line and the midline. The present study was performed to determine which of the four sonographic diameters best differentiates between patients who have liver disease and those who do not. The sonographic liver size was prospectively measured in 50 patients who had acute viral hepatitis and in 50 subjects who had an increased alcohol intake, with data being analyzed in terms of receiver operating characteristic (ROC) curves. The results show that all diameters, except for the midline sagittal, are valuable parameters and that the midclavicular longitudinal diameter is best. The present ROC curves allow one to select a cutoff point that best differentiates between healthy subjects and those having acute viral hepatitis or those with an increased alcohol intake in each diagnostic setting. This analysis also shows that sonographic measurements of liver size may be helpful in differentiating patients who have acute viral hepatitis from those who do not and that it is less helpful in identifying subjects who have an increased alcohol intake.