Preschooler referred with “stomach cysts”

US of multicystic dysplastic kidney — Sagittal US of the right kidney (above) shows it to contain multiple cysts, of varying size, that do not communicate and there is a paucity of renal parenchyma. Sagittal US of the left kidney (below) shows it to be normal.

The diagnosis was right multicystic dysplastic kidney.

Our DDX For This Week Is

View the illustrated DDX of cystic renal mass

School ager who fell off his bike and has abdominal pain

Surgical image of small bowel perforation — Surgical image shows an ileal perforation with the forceps placed through the perforation.

The diagnosis was small bowel perforation secondary to bowel trauma

Pediatric Imaging Pearl of the Week

View the illustrated DDX of solid renal mass

Toddler with presumed urinary tract infection

MRI of Wilms tumor — Sagittal US of the left kidney (upper left) shows a round hyperechoic lesion in the lower pole of the kidney. Axial T2 MRI without contrast of the abdomen (upper right) and coronal T1 MRI without (lower left) and with (lower right) contrast of the abdomen shows a well-circumscribed, solid T1 hypointense and T2 isointense mass in the lower pole of the left kidney that enhances minimally.

The diagnosis was Wilms tumor of the left kidney.

Toddler with a fever

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

The diagnosis was acute pyelonephritis in a patient with vesicoureteral reflux.

School ager with bilateral abdominal masses

CT of Burkitt lymphoma of kidney — Coronal T1 MRI without contrast of the abdomen (upper left) shows bilateral enlarged kidneys which after the administration of contrast (upper right) is seen to be due to multiple non-enhancing renal masses. Transverse US of the liver (below) shows a round hypoechoic mass in the liver, superior and to the left of the gall bladder.

The diagnosis was Burkitt lymphoma with renal and liver involvement.

Our DDX For This Week Is

View the illustrated DDX of solid renal mass

Teenager with a cystic abdominal mass

Surgical image shows a large thin-walled cystic structure arising from the mesentery of the small bowel.

The diagnosis was mesenteric cyst.

School ager with right flank pain

Axial (left) and coronal (right) CT without contrast of the abdomen and pelvis shows mild enlargement of the right kidney and a round calcified lesion at the right ureterovesical junction.

Toddler with urinary tract infection

Excretory phase image from an intravenous pyelogram shows marked dilation of the left renal collecting system and marked dilation of the left ureter throughout its course when compared to the right ureter. No vesicoureteral reflux was seen on a voiding cystourethrogram.

The diagnosis was left congenital megaureter.

Toddler with hypercalcemia

Sagittal US of the left and right kidneys shows echogenic medullary pyramids bilaterally and mild right hydronephrosis.

The diagnosis was nephrocalcinosis and a mild left ureteropelvic junction obstruction.

Newborn with abnormal prenatal ultrasound

Sagittal US of the right kidney shows a lobulated renal contour along the anterior aspect of the right kidney. The left kidney was absent.

The diagnosis was renal fetal lobulations in a patient with a solitary right kidney.

School ager with gross hematuria who is post bone marrow transplant and has received cyclophosphamide

Transverse (above) and sagittal (below) US of the pelvis shows an extremely thick-walled bladder containing echogenic debris and clots.

The diagnosis was hemorrhagic cystitis due to cyclophosphamide therapy.

Female infant with a single perineal opening

Lateral view (left) from a colostogram (lower left contrast collection) shows a rectovesical fistula with contrast filling the patient’s bladder (upper left contrast collection). Oblique view from later in the study (right) shows a filled bladder with a competent bladder neck, a long urethra-urogenital sinus and possibly a rudimentary vagina.

The diagnosis was cloacal malformation.

Teenager with an abdominal mass

Axial CT without contrast of the abdomen shows the right kidney to be normal in size and to contain multiple small low density lesions that when measured demonstrate negative Hounsfield units. The left kidney, which is massively enlarged, also contains multiple small low density lesions as well as one extremely large low density lesion in its anterior aspect.

The diagnosis was angiomyolipoma of the kidneys in a patient with tuberous sclerosis.

Premature newborn with abdominal distension and clinical deterioration

Surgical image of necrotizing enterocolitis — Surgical image shows the bowel was white and necrotic throughout its entire length from the duodenum to the colon. There was no salvageable bowel.

The diagnosis was total necrosis of the intestines due to necrotizing enterocolitis.

Pediatric Imaging Pearl of the Week

View the illustrated DDX of pelvic mass

Toddler with constipation and urinary retention

BE of presacral neuroblastoma — Lateral image from a barium enema performed after an intravenous pyelogram (below) shows anterior displacement and compression of the bladder (to the left of the image) and rectum (in the middle of the image) by a presacral mass. The scout image (above) showed the mass was not calcified.

The diagnosis was presacral neuroblastoma.

Preschooler with abdominal pain

CT of infected urachal cyst — Axial (left) and sagittal (right) images from a CT with contrast of the abdomen shows a midline cystic lesion with a thick enhancing wall and surrounding inflammatory change just inferior to the umbilicus that appears to course to the dome of the bladder on the sagittal image.

The diagnosis was an infected urachal cyst.

Female school ager with left lower quadrant abdominal pain and an abdominal mass

US and CT of ovarian dysgerminoma with torsion — Transverse and sagittal US of the pelvis (above) shows an echogenic and inhomgenous solid mass superior to the bladder. Neither ovary could be visualized. Axial CT with contrast of the abdomen shows a solid non-enhancing midline mass. The mass was found to be tossed in the operating room.

The diagnosis was an ovarian dysgerminoma which was found to be torsed in the operating room.

Female school ager with abdominal pain

CT of ovarian cystadenoma — Axial, coronal and sagittal images from a CT with contrast of the abdomen shows a large cystic mass with thin separations on the right side of the abdomen above the bladder. The uterus and left ovary were unremarkable.

The diagnosis was ovarian cystadenoma

Female infant with pelvic mass

US of hematocolpos — Transverse (above) and sagittal (below) US of the pelvis shows a large cystic structure filled with complex fluid posterior to the bladder which is visible on the right side of the sagittal image. The uterus was identified and was unremarkable and therefore the cystic structure was felt to represent a distended vagina.

The diagnosis was hydrocolpos.

Male preschooler with urinary retention

CT of prostatic rhabdomyosarcoma — Axial CT with contrast of the abdomen shows a soft tissue mass arising from between the bladder and rectum that is invading into the posterior wall of the bladder, resulting in filling defects within the bladder.

The diagnosis was genitourinary rhabdomyosarcoma arising from the prostate and invading the bladder.

School ager with suspected congenital anomaly of the urinary tract

IVP of pelvic kidney — AP image from the excretory phase of a vintage intravenous pyelogram shows a normal position of the right kidney in the right renal fossa. The left renal fossa is empty and the left kidney can be found in the left pelvis, over the left side of the sacrum.

The diagnosis was an ectopic kidney in the pelvis.