Long-term results of the Belsey Mark IV antireflux operation in relation to the severity of esophagitis A retrospective analysis of the results of the Belsey Mark IV operation has been conducted, relating these to the degree of esophagitis present preoperatively. Analysis of 89 patients showed a 91.7% success rate in patients without esophagitis. Good results diminished steadily as the severity of esophagitis increased, giving 76.5%, 75%, 66.7%, and 50% success rates for first-, second-, third-, and fourth-degree esophagitis, respectively. We believe that shortening of the esophagus is an important factor in this. Shortening is obvious in third- and fourth-degree esophagitis but subtle in first- and second-degree esophagitis. We conclude that the Belsey operation is adequate for patients without esophagitis, but for patients with any degree of esophagitis more effective reflux control is needed. 