KUB Signs

Rigler Sign (Double Bowel Wall Sign)

  • Free gas/air is seen on both sides of the bowel causing the bowel wall to be very pronounced

  • Indicates the presence of pneumoperitoneum

  • Radiopaedia article

Phi Angle

  • Angle formed between gastric lap band and spine

  • Normal = 4-58 deg (just remember between 6-60 as it is easier to remember and its very unlikely you’ll be tested on a case of 59 or 5 degrees)

  • If angle is greater than this it suggests compromised lap band

    • If lap band is perpendicular to the spine = bad

References:

  • Case courtesy of J Yeung, Radiopaedia.org, rID: 14905 (Rigler case)

  • Case courtesy of Jeremy Jones, Radiopaedia.org, rID: 8041 (Rigler case)