School ager with progressive abdominal distension and abdominal pain over the last month and new onset urinary retention

CT of constipation causing bladder outlet obstruction
Coronal (left) and sagittal (right) images from a CT with IV and oral contrast of the abdomen shows a hugely distended bladder whose dome nearly touches the inferior margin of the liver. There is a marked amount of stool throughout the colon, especially in the rectum where a fecaloma is pinching off the bladder neck and urethra.

The diagnosis was constipation causing bladder outlet obstruction.

Newborn with marked bilateral hydronephrosis on prenatal US

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.

The diagnosis was posterior urethral valves.

Toddler with right scrotal pain who had suffered non-accidental trauma

CT of testicular hematoma
Axial CT with contrast of the abdomen (above) shows a heterogenous appearance to the enlarged right testicle which is surrounded by an edematous scrotal sac. Sagittal US of the right scrotum (below) again shows the thickened edematous scrotal sac, the heterogenous testicle, and an anechoic fluid collection surrounding the testicle.

The diagnosis was testicular hematoma surrounded by a reactive hydrocele and a scrotal hematoma secondary to trauma.

Infant with enlarged left scrotum and elevated AFP

US of testicular yolk sac tumor
Transverse color doppler US of the scrotum (above) shows the left testicle is hypervascular and much larger in size than the right testicle. Sagittal US of the left testicle (below) shows the testicular enlargement is due to a large round mass in the superior aspect of the testicle that is discrete from the normal testicle inferiorly.

The diagnosis was yolk sac tumor of the testicle.

Infant with non-bilious and bilious vomiting

Surgical image of Meckel's diverticulum
Surgical image shows shows multiple dilated loops of small bowel in the background with a sharp transition point seen in the center of the image in the terminal ileum where on its anti-mesenteric border a diverticulum is seen with an omphalomesenteric duct remnant coming off it. This remnant had been attached to the under surface of the umbilicus, serving as a fulcrum for a small bowel volvulus, resulting in a small bowel obstruction.

The diagnosis was Meckel’s diverticulum causing a small bowel volvulus and a small bowel obstruction.

Infant with urinary tract infection

US of duplicated kidney with ectopic ureterocele and hydroureteropyonephrosis
Sagittal US of the right kidney (upper left) shows a duplicated renal collecting system with the upper pole replaced by a round structure filled with echogenic material. Sagittal US of the right upper pole ureter (upper right) shows a tortuous ureter filled with echogenic material. Transverse US of the bladder (lower left) shows a round structure in the right side of the bladder that has echogenic material in its inferior portion and anechoic material in its superior portion. Sagittal US of the right ureter and bladder (lower right) shows the tortuous right ureter filled with echogenic material on the left side of the image and the rounded structure with the fluid-fluid level in the right side of the bladder.

The diagnosis was acute pyelonephritis in a duplicated kidney with an ectopic ureterocele with hydroureteropyonephrosis throughout the upper pole of the right kidney and right upper pole ureter and ureterocele.