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Objectives: To investigate the accuracy in estimating single kidney glomerular filtration rate(GFR)derived from low dose dynamic contrast-enhanced MR(MR Renography,MRR)and Patlak model in swine with unilateral renal arterial stenosis(RAS)and hydronephrosis on 3.0T.Methods: In this animal care and use committee–approved study,RAS was surgically created in five pigs and hydronephrosis was surgically induced in another five pigs.Dynamic low-dose gadopentetate dimeglumine(0.04mmol/kg)contrast enhanced MR imaging was performed in all ten pigs with a 3.0-T scanner.99mTc-DTPA scintigraphy soon afterwards provided reference standard of single-kidney GFR.Average signal intensities(SI)of region of interest on bilateral renal cortex were measured for each series,weight relative SI increments were calculated and the time-SI curve were plotted.Patlak model was used to analyze the aortic and renal cortical signal intensity vs.time curves(MRR)to obtain split GFR.Values were reported as mean ± standard deviation(SD).GFRs measured with MRR were compared with the reference value from scintigraphy using Pearsons correlation coefficient.The agreements between the two methods were assessed with the Bland-Altman plots and intraclass correlation coefficients(ICC),respectively.Results: Unilateral GFR from MR renography derived from Patlak-Rutland model agreed well with reference measurements(40.72±15.27 ml/min,7.60 –74.90 ml/min)in cortex regions(39.60±12.42 ml/min,7.62–66.40 ml/min)(r =0.836,P =0.000,n=20).Bland-Altman analysis showed that the average difference between GFRMRand reference values was-1.11 ml/min with a 95%confidence interval from-17.46 ml/min to 15.24ml/min,all of 20 coupled GFRs discrpencies were within range of 95%confidence interval.The ICC value was 0.9508(P<0.001).There statistical analysis showed there was a good consistence between GFRMR and standard reference Conclusions: GFRs could be measured with low-dose MR renography and Patlak model,it has good consistence with standard reference from 99mTc-DTPA scintigraphy.