Intrarenal reflux (IRR) involves intrarenal extension of vesicoureteral reflux (VUR) into the tubular system of the kidney.
IRR occurs in 3-10% of cases and can lead to renal injury, which may eventually result in renal scarring. The condition can be diagnosed by micturating cystourethrography (MCUG). It is the main cause of renal injury in patients with VUR.
Radiographic features
MCUG is the main diagnostic tool for IRR. However, according to Darge et al 2, contrast-enhanced harmonic ultrasonography can facilitate the diagnosis along with avoidance of radiation exposure.