A Proposal of a New Index, Liver Index, Based on a Simplified Measurement of Liver Sizes by Ultrasonography-Part 1-
山田 伸夫, 新沢 陽英, 高橋 恒男, 石川 誠
Nobuo YAMADA, Haruhide SHINZAWA, Tsuneo TAKAHASHI, Makoto ISHIKAWA
The Second Department of Internal Medicine, Yamagata University School of Medicine
Liver Index, Liver volume, Ultrasonography, CT scan, Chronic liver diseases
We analyzed the correlation of the ultrasonographically determined dimensions of the liver, and their mathematical product to the liver volume determined by a CT scan in 59 cases of chronic liver diseases undergoing ultrasound examination and CT scans almost simultaneously. The results indicated that the product of LL and LD in the left lobe, and the product of RAL and RAD in the right lobe showed the best correlation with the liver volume. Therefore, we calculated the Liver Index as LL×LD divided by RAL×RAD. When the Liver Index was determined in duplicate almost simultaneously in 64 cases of chronic liver diseases, the variance of the index was as small as 6.6±5.6%. In the 192 healthy controls, the Liver Index did not correlate with sex, age, height, weight or body surface area, and it remained almost unchanged at 0.45±0.10. The upper limit of the normal range of the Liver index was 0.65, and a Liver Index exceeding 0.65 was, therefore, suspected to be abnormal. These results allow us to conclude that the Liver Index, which can be calculated from the left and right lobe dimensions of the liver on two-dimensional ultrasound images, is a useful index for the objective evaluation of morphological changes related to chronic liver disease.