Coorelation of renal doppler ultrasonography and diffusion MRI for renal perfusion evaluation in chronic liver parenchymal disease

WHO defines cirrhosis as a chronic process characterized by fibrosis leading to conversion of normal liver architecture into structurally abnormal diffuse nodules. Cirrhosis is an important health issue due to expenses that are being spent on its protection, diagnosis and treatment as well as its treatment's difficulty. Cirrhosis induces systemic hemodynamic changes such as increase in cardiac output and frequency and decrease in mean arterial pressure and total peripheral resistance. On the contrary in some solid organs such as the kidney, resistance to arteriolar flow increases leading to progressive decrease in organ perfusion. In our study we included 50 healthy controls and 40 cirrhosis patients in between June 2013 and January 2014. Cirrhosis patients were classified with Child-Pugh scores and also fibrosis staging and HAI scores which were revealed by liver biopsies. Creatinine clearences were calculated in order to evaluate kidney functions. Renal arteries, interlobar and interlobular arteries of bilateral kidneys were examined with color doppler ultrasound and at least three values were derived to calculate the mean resistive index for each artery. In upper abdomen MRI protocol we estimated the b value as 600 sn/mm2 in order to provide low perfusion effect and high diffusion effect while obtaining adequate DWI image quality. ADC values were calculated after the images were processed on the work station and bilateral kidneys', also right and left liver lobes' ADC values were measured. When ADC values of cirrhosis patients' and healthy controls' ADC right and left liver lobe values, it was found that cirrhosis patients' right lobe ADC values were significantly lower than the control group. Yet, there was no significant difference among left lobes' ADC values. This could be due to perfusion changes as well as motion artifacts caused by especially left lobe's vessels, heart and bowel movements. While renal perfusion changes in cirrhotic patients were evaluated, first renal Doppler ultrasound results of cirrhosis patients and healthy control were compared and it was found that renal artery resistive indexes (RA-RI) of cirrhosis patients were significantly higher than the control group. It is concuded that in cirrhotic cases renal resistive indexes increased as the subgroup of CHILD classification went from CTP A to CTP C. However there was no statistically signicant difference in these subgroupus. Mean ADC values of right and left kidneys and the creatinine clerance values of cirrhosis patients were also compared. There had been a statistically siginificant decrease in renal ADC values as the creatinine clearence values decline. In conclusion, renal DWI from which the quantitative ADC values were provided is a quick and non-ionizing method which can be used as an effective imaging method in addition to routine laboratory tests and an alternative method for the color Doppler ultrasonography in determining early perfusion changes.