Authors’ contributions
HMH and LCKS contributed equally to this paperPHJ, HMH, PCV and LCKS conceived and developed the idea for the project. PHJ, HMH and LCKS wrote the study protocol. PHJ was responsible for all communication with the ethical committee. HMH and LCKS planned and organized the procedures. PCV performed the colonoscopies. PCV, LCKS and HMH screened the potential participants. ØA performed the viscosity measurementsMarianne Hovig, Martin Myreng and Roy Vestjord at the radiology department at the University Hospital of North Norway Harstad, performed all the X-ray pictures in the study. Pål Løvhaugen (Competence center for diagnostic physics) calculated the radiation dose for the X-ray pictures.PHJ, LCKS and HMH wrote the manuscript. PHJ, PCV, LCKS, HMH, FEJ, ØA and RG performed critical revision for important intellectual content and approved the final version of the manuscript.