Presentation
Retrosternal heartburn, with epigastric discomfort.
Patient Data
Fluoroscopy examination demonstrates a gastric band (proximal radio-opaque ring) in abnormal orientation (more horizontal than normal). The phi angle measurement exceeds the normal range indicating a slipped gastric band. Delayed passage of contrast through the stoma is seen without evidence of obstruction. Repeated episodes of gastro-esophageal reflux were seen. The distal circular radio-opacity represents the port.
Case Discussion
The phi (φ) angle is easily measured. It is measured between a vertical axis of the spine and one along the long axis of the gastric band, A normal angle is between 4-58º, which is considered a useful adjunctive measurement in the assessment of gastric band position.