Regional Renal Blood Flow Measurements Using Radioactive Microspheres in a Chronic Porcine Model with Unilateral Vesicoureteral Reflux

Abstract

95Niobium labeled radioactive microspheres were used to determine regional renal blood flows in a porcine model of chronic sterile vesicoureteral reflux. Unilateral vesicoureteral reflux was surgically created in 5 mini-pigs and regional renal blood flows were determined by microsphere injection 6 months later. The contralateral nonrefluxing kidney acted as a control. There was a significant reduction of flow in the inner cortical regions of the middle (78% of control, p < or = 0.0437) and lower poles (69% of control, p < or = 0.0274), and the juxta-medullary cortical region of the lower pole (67% of control, p < or = 0.0124). There was no difference in flow in the other regions or when comparing whole kidneys. There were no differences between refluxing and nonrefluxing kidneys when comparing ratios of inner to outer cortical flow level by level. These observations are in contrast to those in acutely created vesicoureteral reflux in a porcine model, which had no significant differences in flow in any region using the microsphere technique. Decreases of blood flow in certain cortical regions may help explain some of the physiological changes in vesicoureteral reflux in children and experimental models of reflux.

Color-Doppler sonographic tissue perfusion measurements reveal significantly diminished renal cortical perfusion in kidneys with vesicoureteral reflux

“…[ 21 ] Nevertheless, the same authors found in the same model clear perfusion changes preferentially in the upper and lower pole region. [ 22 ] In another porcine model renal function as well as maintenance of renal perfusion was disturbed after 3–4 months after experimental induction of reflux. [ 23 ] Porcine kidneys are prone to intrarenal reflux due to the fusion of MPs in the upper and lower poles with gaping collecting ducts[ 24 25 26 ] and differ from human kidneys in this aspect.…”

“…and their group. [ 21 22 ] Frauscher et al . found a significantly increased vascular resistance with color-Doppler sonographic measurements and a good correlation to scintigraphy in 46 children with VUR.…”