The evolving uroradiographic evaluation of the lower urinary tract in neonates with myelomeningocele.

Radiographic cystography (VCUG) has been advocated to detect dynamic and anatomic abnormalities of the lower urinary tract in the neonate with myelomeningocele (MM). We reviewed the VCUG in 120 neonates and the radionuclide cystograms (RNC) or cystometrograms (RNCMG) in 30 neonates to reevaluate the role of cystography in this population. Surgery was not required to treat the anatomic abnormalities detected by VCUG. The absence/presence of reflux and a bladder residual volume of greater than 15 cc were the two most important criteria in determining the neonatal voiding regimen. Because RNC provides this information equally well with a much smaller radiation dose and because of the additional functional information available from RNCMG, we now recommend that RNC or RNCMG be used to evaluate the lower urinary tract of neonates with MM.