Endoscopic placement of collagen at the lower esophageal sphincter to inhibit gastroesophageal reflux: a pilot study of 10 medically intractable patients.

Ten highly symptomatic and medically refractory refluxing patients were treated with a new endoscopic technique to decrease gastroesophageal reflux. Cross-linked bovine dermal collagen was injected beneath the mucosa in the area of the lower esophageal sphincter through a 23 gauge needle-tipped catheter. A mean volume of 85 ml of implant was injected in 0.5- to 4-ml increments over 3 to 10 injection sessions. All patients developed objective evidence of decreased reflux by one or more parameters. Nine out of 10 patients had decreased symptoms, and 8 of 9 patients had an increase in lower esophageal pressure after implant injection. Endoscopic implant treatment resulted in statistically significant improvement in symptom scores (p less than 0.001), the standard acid reflux test (p = 0.009), and lower esophageal sphincter pressures (p = 0.002), but not in the endoscopic appearance of the esophagus (p = 0.131). Subjective and objective improvements in reflux parameters generally lasted 6 to 9 months with return toward pretreatment status by 12 months. Antibodies to bovine collagen developed in 5 of 10 subjects with no clinical sequelae and no apparent reactivity with human collagen. The technique is not difficult to perform and is well tolerated by patients, and the results indicate the potential for more general use with a more suitable implant material.