URODYNAMICS AND MASSIVE VESICOURETERAL REFLUX

Purpose: Urodynamic studies are the key to management and reconstructi on of bladder pathology. In the face of high grade vesicoureteral refl ux measured pressures and volumes reflect the combined storage charact eristics of the upper and lower tracts. We examined the influence of h igh grade reflux on measured volume and compliance (change in volume/c hange in pressure), Materials and Methods: A total of 18 children with high grade vesicoureteral reflux underwent urodynamic evaluation with and without ureteral occlusion. Occlusion was created in the operativ e suite using ureteral occlusion balloons, After fluoroscopic confirma tion of the absence of reflux bladder pressure was measured during fil ling at a rate of 12.5 cc per minute. During ureteral occlusion bladde r capacity was defined as leakage around the urethral catheter, bladde r pressure greater than 40 cm. water or volume exceeding estimated bla dder capacity for age, as determined by the formula, bladder capacity in ml, = (age + 2) x 30. The ureteral occlusion balloons were removed and similar measurements were obtained in the presence of reflux. Comp liance was calculated for the first and last 50% (initial and terminal compliance, respectively) of bladder capacity. Results: Mean initial compliance without and with ureteral occlusion was 19.6 versus 13.2 cm , water (33% decrease), Mean terminal compliance without and with occl usion was 12.9 versus 8.6 cm, water (33% decrease, p < 0.005), Bladder capacity decreased a median of 16%. Underlying bladder pathology was evaluated to determine the patients who would benefit most from ureter al occlusion studies. Patients with neurogenic bladder, pasterior uret hral valves and primary reflux had similar changes in measured complia nce with ureteral occlusion. Patients with poor terminal compliance wi thout occlusion and those with bilateral vesicoureteral reflux had gre ater changes in compliance with occlusion but these changes were not s tatistically significant (p > 0.05). Age was indicative of a significa nt decrease in terminal compliance with ureteral occlusion, since olde r patients had the greatest change in terminal compliance (p < 0.005). Conclusions: High grade vesicoureteral reflux influences measured low er tract volume and compliance.