Perforated Viscus

  • Findings: Free gas (most important finding). In the absence of known benign cause, diagnosis is perforated viscus. Tract of gas from distal stomach is visualized posteriorly, which was the source.

  • Objectives:

    • To identify pneumoperitoneum and have a basic differential diagnosis

    • To practice identifying the source of pneumoperitoneum

  • Protocolling:

    • Contrast enhanced CT

  • Key points:

    • Anatomy:

      • Review small and large bowel anatomy

    • Differential diagnosis:

      • Perforated viscus (PUD, ischemic bowel, appendicitis, diverticulitis, etc)

      • Post-operative

      • Peritoneal dialysis

    • If perforated viscus is suspected, patient will go to OR.

    • Identifying the source of free gas:

      • Amount and location of gas collections (assess for intra and retroperitoneal gas)

      • Look for:

        • Localized air bubbles

        • Focal bowel wall thickening

        • Bowel wall discontinuity

        • Focal pathology (i.e. appendicitis, diverticulitis, PUD)