The value of sonography for estimation of liver volume by using a simple geometric formula ascertained in cadaveric livers.

ABSTRACT

Accurate assessment of liver size and its volume are important. However, as the clinical methods do not produce reliable results especially when the liver is shrunken, and the previous attempts to accurately assess liver volume by radio-isotopes, CT scans and computer assisted ultrasonography have not gained popularity due to high cost and complex techniques, the need to devise a simpler technique for estimation of liver volume continues. In doing so, we estimated volume of 10 cadaveric livers by water displacement technique to serve as the reference value. Thereafter, assuming the shape of liver like a right-angled pyramid, we calculated its volume by a simple geometric formula of '1/2 abc'. However, a reduction of 15% was made from this to compensate for depression on the inferior surface of liver. This method was subsequently implemented to assess liver volume of 14 healthy individuals and 20 patients of fulminant hepatic failure (FHF) by using ultrasonography. Our findings revealed smaller liver volume in Indians as compared to the reported Western figures, and a significantly smaller liver volume in females as compared to males. The liver volume of 6 FHF patients who died was significantly smaller (696.5 +/- 143.5 cm3) as compared to that of the 14 FHF patients who survived (1083 +/- 365.3 cm3). Moreover, mortality rate was 100 per cent in 3 patients of FHF who showed markedly shrunken globular liver with a liver volume of less than 500 cm3. Thus, a markedly reduced liver size in FHF patients suggests a poor prognosis. However, since the number of FHF patients in the present series is small, it is our contention that a larger series is mandatory to confirm the findings of the present study.