Objectives: Most available studies investigating the diagnostic accuracy of color Doppler voiding urosonography in the detection of vesicoureteric reflux used an echo contrast agent. It is unknown whether echo contrast agents are necessary for diagnosis or follow-up of vesicoureteric reflux. We compared color Doppler voiding urosonography without contrast enhancement and direct radionuclide voiding cystography in the detection and grading of vesicoureteric reflux with respect to the sex and age of patients as well as the severity of reflux.
Methods: In the 66 patients enrolled (56 girls and 10 boys), 132 renoureteral units were investigated. All patients under went Doppler voiding urosonography and direct radionuclide voiding cystography within 3 hours. Direct radionuclide voiding cystography was used as the reference standard.
Results: Our results indicate good overall sensitivity (83%) and specificity (77%) for color Doppler voiding urosonography without contrast enhancement in comparison with direct radionuclide voiding cystography. As the age of the patients decreased, the sensitivity of urosonography increased, reaching 100% among patients younger than 1 year. In the comparison of different grades of reflux severity, we found that the sensitivity and specificity were elevated as the grade increased (both parameters reaching 100% in the most severe cases). Severity grading was equal between the two methods.
Conclusions: We have shown that Doppler voiding urosonography without contrast enhancement is a comparably reliable method versus direct radionuclide voiding cystography in the detection and grading of vesicoureteric reflux, especially at higher grades of reflux and in children younger than 1 year.