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Slipped gastric band

Case contributed by Dr Henry Knipe


Upper abdominal pain, nausea.

Patient Data

Age: 35
Gender: Female

Fluoroscopy demonstrates a gastric band device with a more horizontal lie than normal. The phi angle measures 63 degrees (normally 4-58 degrees), indicative of a slipped gastric band. 

Annotated image

The phi (φ) angle is easily measured. It is measured between a vertical line oriented with the spine and one along the long axis of the lap band - a normal phi angle is between 4 and 58 degrees. The lap band should also be "flat" and not "obliqued" so that it appears as a horizontal block rather than a ring. 

Case Discussion

The phi angle is a useful adjunctive measurement in the assessment of gastric lap band position. This patient went to to have a revision surgery for correction of this slipped band. 

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Case information

rID: 30761
Published: 2nd Sep 2014
Last edited: 15th Jan 2020
Inclusion in quiz mode: Included

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