Renal function study on computed tomography perfusion of distal ureteral obstruction in rabbits

Objective To explore the value of anatomical and functional assessments of computed tomography(CT) perfusion imaging in a rabbit model of distal ureteral obstruction. Methods A total of 35 male New Zealand rabbits(2-2.5 kg) were randomly divided into two groups of normal control(A, n=15) and experiment(B, n=20). And ureteral cannula depressing method was employed for modeling of unilateral distal ureteral obstruction while there was no treatment in control group. Before surgery, single-photon emission computed tomography(SPECT) was used to compare kidney functions to ensure that kidney function of samples was normal and there was no individual inter-group difference(Pboth kidneys =0.557>0.05, Pleft kidney=0.298>0.05, Pright kidney=0.937>0.05). Then left unilateral distal ureteral obstruction model was established. SPECT and CT perfusion imaging were performed for two groups at 4 weeks after surgery. The parameters blood flow(BF), blood volume(BV) of renal cortex and medulla, permeability surface(PS) and mean transit time(MTT) were recorded. And glomerular filtration rate was measured by SPECT. And statistical analyses were performed. Results Blood flow(BF), blood volume(BV) of renal cortex and medulla decreased significantly in experiment group(P=0.000 0.05, Pmedulla=0.741>0.05). There was a high degree of positive correlation between BF, BV of cortex as well as medulla and GFR. However, no correlation existed between MTT, PS and GFR. Conclusions The animal model of distal ureteral obstruction is both simple and feasible. CT renal perfusion imaging provides quantitative assessments of cortex and medulla blood flow perfusion and renal function of hydronephrosis. There is a good correlation between BF, BV of renal cortex and medulla and GFR. Key words: Ureteral obstruction; Model, animal; Computer tomography