Imaging Case of the Week 167 Answer

The abdominal x-ray shows a lap band O sign, indicative of band slippage. There is distension of the gastric fundus above the gastric band.

Lap band O sign

The gastric lap band on an AP abdominal x-ray, should have the following features –

  • The phi angle (the superior angle formed by the longitudinal axis of the lap band and the spinal column should be between 4 and 58 degrees.
  • The band should have a rectangular appearance on the x-ray because its anterior and posterior aspects are superimposed.