Presentation
Upper abdominal pain, nausea.
Patient Data
Age: 35 years
Gender: Female
From the case:
Slipped gastric band
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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.
From the case:
Slipped gastric band
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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.