Comparison of direct radionuclide cystography with micturating cystourethrography for the diagnosis of vesicoureteric reflux, and its correlation with cystoscopic appearances of the ureteric orifices.

Forty-eight patients with strong clinical suspicion of vesicoureteric reflux (VUR) as the cause for their renal disease; were subjected to direct radionuclide cystography and roentgenographic micturating cystourethrography for its detection. Forty-four of them underwent cystoscopy under local anaesthesia to document the position and appearance of the ureteric orifices. Of the 92 kidney-ureter 'units' available for study, 20 had reflux positive on micturating cystourethrography and 22 had direct radionuclide cystography positivity. Two of the three units picked up on direct radionuclide cystography but missed on micturating cystourethrography were severe refluxes up to the renal pelvis. On the other hand, one unit missed on direct radionuclide cystography but picked up on micturating cystourethrography was a lower ureteric reflux. The sensitivity and specificity of direct radionuclide cystography to detect VUR as compared to micturating cystourethrography is 95% and 95.8% respectively. The localization and appearance of ureteric orifices which were classified as per Lyon's classification greatly enhanced the predictive value of determining past or present VUR. Patients with golf-hole orifices placed laterally had 100% incidence of reflux. Thus, combining direct radionuclide cystography with cystoscopy may enhance the predictive value for diagnosis of VUR even higher than a micturating cystourethrography study.