KUB (figure 01):
1. Increased opacity in whole abdomen with relative decreased
   bowel gas in middle and lower abdomen, nature to be determined.
2. Recommendation: Further evaluation with ultrasound of abdomen
   to exclude intraabdominal mass. Thank you!

Ultrasound (figure 02):
1. Big heterogeneous mass in abdomen, behind bladder.
2. Distended bladder and bilateral hydronephrosis, suggesting
   bladder outlet obstruction with bilateral obstructive uropathy.

CT (figure 03-19):
CT scan of abdomen with pre- and post- intravenous contrast, and
 with multiplanar reconstruction (after negative barium enema
 study):

1. A well-defined homogeneous enhancing huge mass, about 12x9x5cm,
   in lower abdomen, with faint calcifications (small white arrows
   in fig.3) and small cystic component, nature to be determined.
2. Marked mass effect of the lesion with compression of
   intraabdominal organs, including bilateral hydronephrosis,
   suggesting the tumor origin from retroperitoneum.
3. Small ascites, nature to be determined.
4. Contrast media retention in GI tract (yellow arrow in fig.3),
   may due to post contrast study.
5. Distended bladder with much intraluminal air.
   S/P Foley's catheter (red arrow in fig.3).

MRI (figure 20,21):
MRI of abdomen with T2 weighted echo train spin echo with fat
 saturation, multi-angle projective thick MR urography, and with
 intravenous gadolinium-enhancement:

1. A well-defined mild long T2 huge tumor with relative
   homogeneous contrast enhancement, about 12x9x5cm, in lower
   abdomen, with a long T2 and some short T2 intratumorous areas,
2. Marked mass effect of the lesion with compression of
   intraabdominal organs and lateral displacement of bilateral
   ureters (arrows in fig.21), suggesting the tumor origin from
   retroperitoneum.
3. Bilateral moderate hydronephrosis and hydroureter and
   marked distended bladder, possibly due to bladder outlet
   obstruction from posterior compression by the tumor.
   Much air retention in bladder.
4. Small ascites, nature to be determined.

Surgery (figure 22-25):
Laparotomy with tumor excision

Pathology:
Neuroblastoma