2013 Radiology Exam - Abdomen Case 1

Signalment: 11.5 year old male English Setter
History: Acute onset vomiting
Radiographs: Three images of the abdomen: Right lateral, left lateral, ventrodorsal projection

Observation:

  • There is a focal mass effect caudal to the stomach with displacement of adjacent organs (caudal displacement of the transverse colon, cranial displacement of the stomach).
  • The duodenum is gas filled and mildly dilated on the VD and left lateral projections.
  • Loss of serosal detail in the right cranial abdomen.
  • Increased soft tissue opacity in the right cranial abdomen with widening of the pyloroduodenal angle.

Synthesis:

  • Pancreatitis is the primary differential diagnosis. Pancreatic neoplasia, abscess, or pseudocyst considered as differential diagnoses. Detail loss indicative of regional peritonitis or effusion such as hemorrhage or paraneoplastic effusion.

Case Management:

  • Abdominal ultrasound
  • Thoracic radiography

Notes on the case: Many candidates noted the duodenal dilation, but many struggled to identify the subtle mass effect or regional detail loss. Duodenal dilation was incorrectly assumed by some to be due to mechanical obstruction, despite the fact the duodenum tapers distally. Successful candidates tended to refer to the clinical history of acute vomiting, and noted that pancreatitis was consistent with that history. Some candidates noticed the vertically oriented lines on the VD projection and were concerned about an abdominal or subcutaneous foreign body, rather than an artifact from the positioning trough.