Pediatric Vesicoureteral Reflux

Etiology: incompetent vesicoureteral valve, ureteral insertion into ureterocele or bladder diverticulum
VCUG: grading – Grade I (reflux only in ureter) / Grade II (reflux into non-dilated collecting system) / Grade III (reflux into mildly dilated collecting system) / Grade IV (reflux into moderately dilated collecting system) / Grade V (reflux into markedly dilated collecting system)
RNC: less spatial resolution than VCUG but has lower radiation dose and continuous monitoring, excellent for following reflux once it is diagnosed
US: artificial collagen injections at vesicoureteral valve appear as echogenic bump at base of bladder
Treament: lower grades of reflux can be treated temporarily with artificial collagen injections at vesicoureteral valve
Clinical: lower grades of reflux usually resolve on their own as patient grows older

Radiology Cases of Vesicoureteral Reflux

Radiology Cases of Vesicoureteral Reflux Grade I

Radiology Cases of Vesicoureteral Reflux Grade II

VCUG of posterior urethral valves — Oblique image from a voiding cystourethrogram (left) shows left vesicoureteral reflux up into a non-dilated left renal collecting system (Grade 2 vesicoureteral reflux). The posterior urethra appears dilated. Magnified lateral image of the urethra (right) shows the dilation of the posterior urethra is due to a fixed narrowing in the posterior urethra.

Radiology Cases of Vesicoureteral Reflux Grade III

US of acute pyelonephritis / acute lobar nephronia — Sagittal US of the right kidney (above) shows an ill-defined hypoechoic mass in the right upper pole that is obscuring the normal outline of the echogenic fat in the renal hilum. The mass was hypoperfused on color and power doppler US. AP image from a voiding cystourethrogram (below) shows bilateral vesicoureteral reflux, grade II on the left and grade III on the right

US and VCUG of vesicoureteral reflux and neurogenic bladder — Sagittal US of the right kidney (above) shows moderate hydronephrosis. AP image from a voiding cystourethrogram (below) shows right-sided vesicoureteral reflux into a dilated collecting system and a trabeculated bladder. The urethra was normal in appearance.

VCUG of ectopic ureter inserting into the urethra — Sagittal US of the right kidney (above left) is normal while sagittal US of the left kidney (above right) shows a parenchymal bar between the upper and lower pole collecting systems. AP image of the bladder (below left) obtained during filling of the bladder during a voiding cystourethrogram (VCUG) shows right-sided vesicoureteral reflux into a dilated collecting system with the right ureter inserting normally into the base of the bladder. AP image of the bladder (below right) obtained during the voiding phase of the VCUG shows new left-sided grade I vesicoureteral reflux with the left ureter inserting into the urethra.

Radiology Cases of Vesicoureteral Reflux Grade IV

CT of reflux nephropathy and VCUG of vesicoureteral reflux — Coronal CT with contrast of the abdomen (left) shows a normal appearing left kidney and a shrunken right kidney with diffuse loss of renal parenchyma and scarring. AP image from a voiding cystourethrogram (right) shows left grade II vesicoureteral reflux and right grade IV vesicoureteral reflux.

US of cystic renal dysplasia — Sagittal US of the kidneys (above) show small echogenic kidneys bilaterally with some cysts but no hydronephrosis. AP image from a VCUG (below left) shows bilateral grade 4 vesicoureteral reflux with intrarenal reflux and the bladder is trabeculated. Lateral image from the VCUG (below right) shows a urachal diverticulum arising from the dome of the bladder anteriorly. The urethra was normal.

Radiology Cases of Vesicoureteral Reflux Grade V

VCUG of ectopic ureterocele — AP images from a voiding cystourethrogram (above) show a lucent filling defect in the base of the bladder. Oblique image (below) shows reflux into an extremely dilated right renal collecting system. The right ureter inserts into a dilated structure that is inside and outside of the bladder.

VCUG of posterior urethral valves — AP image from a voiding cystourethrogram (above) shows bilateral grade 5 vesicoureteral reflux, right greater than left, and a narrow pinecone-shaped bladder in the inferior midline aspect of the image. Lateral image of the urethra taken during the voiding phase of the voiding urethrogram (below) shows marked dilation of the posterior urethra and a thin lucent membrane at the transition zone where the urethra assumes a more normal caliber.