Comparative study of color doppler voiding urosonography without contrast enhancement and direct radionuclide voiding cystography for diagnosis of vesicoureteric reflux in children

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 underwent 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—Wehave 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