Preoperative Evaluation of Liver Parenchyma of Potential Donors in Living Donor Liver Transplantation.

BACKGROUND

Hepatic steatosis carries a risk of postoperative liver dysfunction in donors and graft nonfunction in recipients. This article discusses the evaluation of fatty infiltration in donor liver parenchyma on multidetector computed tomography.

MATERIALS AND METHODS

The methods of hepatic fat estimation include measurement of hepatic attenuation in HU and calculation of the liver attenuation index (LAI). Liver attenuation values reflect the degree of steatosis. Average attenuation of liver parenchyma is calculated by placing the circular region of interest of at least 1 cm area at multiple places in the liver on noncontrast CT images. Splenic attenuation is measured by placing the circular region of interest at its upper, middle, and lower poles. The LAI is the difference between mean hepatic attenuation and mean splenic attenuation.

RESULTS

A total of 52 donors were evaluated as potential recipients (34 men, 18 women; mean age, 33.2 years; range, 23-55 years). In 34 donors liver attenuation index (LAI) values were from 2 HU to 22 HU. An LAI > 5 HU correctly predicted the absence of significant macrovesicular steatosis. These donors were acceptable for a liver transplant. The LAI values of -10 to 5 HU were suggestive of mild to moderate steatosis (6%-30%); 18 (34.6%) volunteers did not proceed to donation because of negative LAI < -5 HU. In 2 cases with LAI of -7 and LAI of -8 liver biopsy was performed, and 30% steatosis was confirmed in the pathohistologic examination. Unacceptable liver biopsy result was considered as contraindication for donation. The LAI values of < -10 HU were suggestive of moderate to severe hepatic steatosis of 30% or greater. In these cases liver biopsy is not needed, as such donors are not acceptable for liver transplant.

CONCLUSION

Computed tomography imaging provides a detailed evaluation of fatty infiltration in donor liver parenchyma.