Aim: To determine the frequency of identification of the triradiate fold during colonoscopy and evaluate its reliability as a marker of caecal intubation.
Methods: One hundred consecutive patients undergoing colonoscopy in a tertiary hospital colorectal unit from May to September 2013 were studied. Video documentation of the caecum was recorded and shown to consultant colorectal surgeons on the unit. Each reviewer was asked through a series of questions to independently identify the triradiate fold. The main outcome was the frequency of visualisation of the triradiate fold in the caecum.
Results: The triradiate fold was seen on average in 18% of cases, but inter-observer agreement was poor. There were only four patients (4%) in which all reviewers agreed on the presence of a triradiate fold. In patients who had undergone previous appendicectomy, the appendiceal orifice was less frequently seen compared with patients who had not undergone appendicectomy.
Conclusion: The triradiate fold is infrequently seen during colonoscopy and is therefore an unreliable landmark of caecal intubation.
Keywords: Appendiceal orifice; Caecal intubation; Colonoscopy; Prospective study; Triradiate fold.