Ileocolic nipple valve anastomosis for preventing recurrence of surgically treated Crohn's disease. Long-term follow-up of six patients. To prevent coloileal reflux after ileocecal resection, an ileocolic nipple valve anastomosis was constructed in six patients with Crohn's disease. The patients were observed for more than 7 years and were compared with 21 Crohn patients in whom conventional end-to-end ileocolic anastomosis was performed during the same period. The outcome was more favorable in the group with nipple valve anastomosis, i.e., longer interval between surgery and symptomatic relapse, and tendency to less frequent recurrence and re-resection. An association was found between radiologically preserved nipple valve and remission, and two patients with intact valve at long-term follow-up remained symptom-free. The observations implied that protection of the terminal ileum from coloileal reflux after ileocecal resection for Crohn's disease may favorably influence the prognosis. 