Comparison of tomographic kidney volumes measured by semiautomatic segmentation method with scintigraphic split renal function in predicting posttransplant kidney functions.

Introduction: In this study, it was aimed to compare scintigraphic split renal function (SRF) and computed tomographic (CT) kidney volumes by semiautomatic segmentation method in predicting graft functions after kidney transplantation.

Methods: One hundred and twelve patients (77 males, 35 females) who had a living-donor kidney transplant between 2015 and 2017 in our centre were included in the study. While SRF was calculated with technetium-99m-diethylenetriaminepentaacetic acid ( Tc-DTPA) scintigraphy, CT angiography was used for volumetric calculations.

Results: CT-volumetric measurements, especially renal cortical volume (RCV: 103.8 ± 20 ml) and ratio to body mass index (RCV/BMI: 4.45 ± 1.3) were found to be more significant than Tc-DTPA-SRF in predicting graft functions. The correlations between SRF and RCV with 6th-month estimated glomerular filtration rate (eGFR) (rSRF: 0.052, rRCV: 0.317, p = 0.041) and 1st-year eGFR (rSRF: 0.104, rRCV: 0.374, p = 0.033) were found to be more significant in favour of RCV. The correlation between SRF/BMI and RCV/BMI with 1st-, 6th- and 12th-month eGFR (respectively, p = 0.02/0.048/0.024) were found to be more significant in favour of RCV/BMI. Although univariate analysis showed a significant relationship between most volumetric measurements and 1st-year graft functions, in multivariate analysis only RCV [odds ratio (OR): 1.04 (1.01-1.07), p = 0.023] and RCV/BMI [OR: 2.5 (1.27-5.39), p = 0.013] showed a significant relationship between graft functions.

Conclusion: In our study, it was shown that CT-based renal volumetric measurements, especially RCV and RCV/BMI, predicted graft functions more strongly than scintigraphic Tc-DTPA-SRF.