title: Vesicoureteral refux detection in children: a comparison of the midline-to-orifice distance measurement by ultrasound and voiding urosonography.
abstract: BACKGROUND
  Due to the questionable clinical role of vesicoureteral reflux (VUR) and the search for noninvasive, radiation-free procedures sufficiently reliable to detect VUR, we compared the correlation between the midline-to-orifice distance (MOD) measured by ultrasonography (US) and echo-enhanced voiding urosonography (VUS) for detecting VUR in children. The aim of the study was to determine whether measuring MOD by US could be a reliable predictor of VUR in children.
  
  
  METHODS
  A total of 116 children, aged 0.25-84 months, with 232 potentially refluxing units were investigated simultaneously by measuring the MOD and performing VUS. Indications for cystography were urinary tract infection and follow-up of a previously detected VUR. VUS was performed after the MOD measurement. The results were analyzed with VUS as the reference method.
  
  
  RESULTS
  The MOD was significantly larger in VUR grade III (10.7 mm; p = 0.003) and VUR grade II (9.9 mm; p = 0.001) refluxing units than in non-refluxing units (7.8 mm), even when controlling for the estimated volume/expected maximal capacity (Vest/Vmax) ratio. A MOD cutoff value of 7.4 mm was chosen as a predictor of either the presence or absence of VUR; the sensitivity and specificity of this cutoff measurement for VUR detection were found to be 89 and 24%, respectively.
  
  
  CONCLUSIONS
  Despite the statistically significant difference between the MOD of refluxing versus non-refluxing units identified in our study, the MOD measurement needs further evaluation to determine its potential value as a diagnostic tool for the detection of VUR.
authors.affiliation: Department of Pediatric Nephrology, University Medical Centre Ljubljana, Ljubljana, Slovenia. nina.battelino@mf.uni-lj.si.
authors.forename: Nina
authors.initials: N
authors.lastname: Battelino
authors.affiliation: Department of Pediatric Radiology, University Medical Centre Ljubljana, Ljubljana, Slovenia.
authors.forename: Damjana
authors.initials: D
authors.lastname: Ključevšek
authors.affiliation: Department of Pediatric Radiology, University Medical Centre Ljubljana, Ljubljana, Slovenia.
authors.forename: Mojca
authors.initials: M
authors.lastname: Tomažič
authors.affiliation: Department of Pediatric Nephrology, University Medical Centre Ljubljana, Ljubljana, Slovenia.
authors.forename: Tanja Kersnik
authors.initials: TK
authors.lastname: Levart
mesh_terms: D002648:Child; D002675:Child, Preschool; D003287:Contrast Media / Q000008:administration & dosage / Q000009:adverse effects; D000070621:Cystography / Q000009:adverse effects / Q000379:methods; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods; D014513:Ureter / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D001743:Urinary Bladder / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D014552:Urinary Tract Infections / Q000000981:diagnostic imaging; D014718:Vesico-Ureteral Reflux / Q000145:classification / Q000000981:diagnostic imaging*
chemical_list: D003287:Contrast Media
keywords: Children; Midline-to-orifice distance; Noninvasive method; Vesicoureteral reflux; Voiding urosonography