Contrast-enhanced Voiding US for Grading of Reflux in Adult Patients Prior to Antireflux Ureteral Implantation1

PURPOSE: To prospectively assess contrast material–enhanced voiding ultrasonography (US) for grading of vesicoureteral reflux (VUR) and to compare results with those of voiding cystourethrography (VCUG) in adult patients undergoing antireflux ureteral implantation. MATERIALS AND METHODS: Thirty-seven consecutive adult patients who had undergone renal transplantation with Politano-Leadbetter (18 patients) or Lich- Gregoire (19 patients) technique were included on the basis of previous urinary tract infections (UTIs) and time elapsed after renal transplantation. Exclusion criterion was current UTI. US was performed by one of two sonologists with injection of saline and microbubble suspension and was recorded on videotape. Sonologists assigned VUR diagnosis in consensus after videotape review. VCUG was performed by one of two radiologists immediately after US. Radiologists were blinded to US findings and assigned VCUG diagnoses in consensus. Contingency table was used to compare US and VCUG. Agreement between US and VCUG was determined with statistics. RESULTS: With VCUG, VUR was diagnosed in 15 patients and not diagnosed in 22 patients. US and VCUG results were in agreement in 14 patients with VUR and 21 patients without VUR. US sensitivity and specificity for detection of VUR were 93% (14 true-positive results in 15 abnormal cases) and 95% (21 true-negative results in 22 normal cases), respectively. Agreement between US and VCUG was 95% (0.89, P .001). In 11 of 14 patients, VUR grades were in agreement for US and VCUG. In three of 14 patients, US indicated a higher grade than did VCUG. VUR was diagnosed in seven of 18 Politano-Leadbetter cases and eight of 19 Lich-Gregoire cases. CONCLUSION: A high rate of agreement was seen between voiding US and VCUG.