An Experimental Study of MSCT Perfusion in the Half Functional Assessment of Hydronephrotic Kidney

Objective To evaluate the diagnostic value of MSCT perfusion in assessment of half renal function of hydronephrotic kidney by measuring perfusion parameters of hydronephrotic model with MSCT perfusion techniques.Materials and Methods 20 healthy adult male rabbits aged more than 8 weeks with experimentally induced partial obstruction of right ureter were performed sequential MSCT perfusion,SPECT and CDFI before and 4 weeks after the establishment of hydronephrotic model.The hydronephrotic kidneys were examined at microscopy.Results Pelvicalyceal dilatation and renal parenchymal thinning were found on MSCT.BF and BV values in both renal cortex and medulla were significantly lower than those in the control group(P(0.01).No significant change in MTT was found and PS of renal cortex was slightly lower than that before obstruction but not significantly while PS of renal medulla was significantly lower than that in the control group(P0.01).Color duplex flow imaging(CDFI) showed a significant lower peak systolic velocity(PSV) in both renal arteries and veins than that before the obstruction((P0.05)and a more significant decline in end diastolic velocity(EDV)(P0.01).There was a significant higher resistive index(RI) in the renal and intrarenal arteries 4 weeks after the obstruction(P0.01).On SPECT,glomerular filtration rate(GFR) of the obstructed kidneys were much lower than those before the obstruction(P0.001),Tb were much longer(P(0.001) and T_(1/2 were much longer which had no practical significance in measurement.Histologically,the specimen of obstructed kidneys showed cystic dilated renal tubules with some atrophic renal tubules.The tubular epithelial cells were flat.Lobular structure of some of the glomerulum still remained.Intertubular distance widened because of interstitial fibrosis.Cloudy swelling of the tubular epithelium and prolate nucleus were found.Conclusion BF and BV are perfusion parameters that have the most significance in the post obstructive renal cortical and medullar.MSCT perfusion parameters were consistent with the renal hemodynamic changes reflected by PSV,EDV and RI measured by CDFI.MSCT with perfusion technique can provide anatomic images of high temporal and spatial resolution which the renal function highly accord with that with CDFI.With advance in the software,MSCT perfusion will be of great value in the assessment for renal function.