Predictability Of 64-slice CT Perfusion Imaging In The Restorability Of Renal Function Of Hydronephrotic Kidney

Objective To approach the value of multi-slice spiral computed tomography perfusion imaging in assessment of renal function of unilateral hydronephrotic kidney and restorability of renal function of hydronephrotic kidneys with unilateralpartial ureteric obstructed rabbit model.Material and Method 30 healthy adult male rabbits were involved in the study,aged more than 8 weeks and weighted 2.0~3.0Kg. Six were selected at random as controls before operation and were performed MSCT scaning and SPECT examination. Other twenty four with experimentally induced partial obstruction of left ureter,six were selected at random respectively at 1 week,3 week,5 week,7 week(respectively called as 1 week group,3 week group,5 week group and 7 week group)were performed MSCT perfusion imaging and SPECT examination then obstruction was released in 1 week group,3 week group and 5 week group. 3 group rabbits were fed for 2 months at the same situation and were again performed MSCT scaning. Hydronephrotic kidneys were examined at microscopy at different stages.Results (1) After obstruction,BF and BV value of renal cortex and medulla gradually decrease than those in the contral group,there were significant change bewteen different groups(P<0.05). MTT value of renal cortex and medulla was prolong,P value of renal cortex and medulla was lower. MTT value and P value of renal cortex and medulla were no significant change between the control group and 1 week group,3 week group,there are significant chang in 5 week group and 7 week group. On SPECT, glomerular filtration rate (GFR) of the obstructed kidneys were much lower than those before the obstruction(P<0.05),Tb was much longer (P<0.05) and T1/2 was much longer(P<0.05). After partial ureteric obstruction,blood flow(BV) and boold volume(BV) of the left renal cortex and medulla gradually decreased,there were significant difference between 4 groups(P<0.05). BF and BV value of left renal cortex and medulla in 1 week group increased significantly after the release of obstruction(P<0.05), but no significant difference between in 1 week group and contral group(P>0.05). BF and BV value of left renal cortex and medulla in 3 week group were no change after the release of obstruction (P>0.05), but significant difference between in 3 week group and contral group. BF and BV value of left renal cortex and medulla in 5 week group decreased significantly after the release of obstruction(P<0.05), and significant difference between in 5 week group and contral group(P<0.05). (2) Histologically,renal pelvis and renal tubules dilated withsome atrophic renal tubules.Intertubular distance widened because of interstitial fibrosis. there was a positive correlation between the duration of obstruction and the seriousness of pathologic changes Those chang mentioned above become more serious as time went on.Conclusion BF and BV value in MSCT perfusion parameters have the most significance in obstructive renal cortex and medulla,and both chang parallel resultsof SPECT. Chang of MTT and P value probobly are relative to the fibrotic degree of hydronephrotic kidney. MSCT perfusion imaging provide a novel approach for functional examination of hydronephrotic kidney,can provide information notonly morphologically but also functionally and is valuable in predictability of therestorability of renal function of hydronephrotic kidney.