Magnetic Resonance Voiding Cystography in the Diagnosis of Vesicoureteral Reflux: Comparative Study with Voiding Cystourethrography

ABSTRACT

PURPOSE: To evaluate the availability of magnetic resonance (MR) voiding cystography for the diagnosis of vesicoureteral reflux (VUR) and to compare the sensitivity of MR voiding cystography (MRVC) with that of radiographic voiding cystourethrography (VCUG) in the detection of VUR. MATERIALS AND METHODS: MRVC was performed upon 20 children referred for investigation of VUR. Either coronal T1-weighted spin-echo or spoiled gradient-echo images were obtained before and after transurethral administration of a mixture of normal saline and gadopentetate dimeglumine, and immediately after voiding. The findings of MRVC were compared with those of VCUG performed within 6 months of MRVC. RESULTS: VUR was detected in 23 ureterorenal units (16 VUR's by both methods, five VUR's by VCUG, and two VUR's by MRVC). The sensitivity of VCUG and MRVC in detecting VUR was 91.3% (21/23) and 78.3% (18/23), respectively. MRVC detected renal scarring in 15 out of 17 kidneys with scintigraphically detected renal scarring. CONCLUSION: Although MRVC is slightly less sensitive than VCUG in the detection of VUR, it can be used for the diagnosis of VUR and renal scarring simultaneously, and thus will reduce the radiation hazard.