Does Endoscope Position Detecting Unit Facilitate a Complete Colonoscopy Examination (UPD-3)

As the incidence of colorectal cancer (CRC) has been rapidly rising in Asian countries, more and more screening colonoscopies are now being performed for prevention or early detection of this fatal disease. Complete colonoscopy as indicated by caecal intubation is essential to make it a reliable screening tool for colorectal cancer or polyps. Cecal intubation rate is highly variable and dependent on individual experience. Colonic looping is the commonest cause of incomplete colonoscopy. Magnetic endoscope imaging (MEI) is a non-radiological imaging technique to provide real time, three-dimensional image and position of the colonoscope during the procedure. It may facilitate straightening of colonic loops and hence cecal intubation.

The investigators aim to evaluate the benefit of MEI in term of cecal intubation rate across endoscopists of all levels of experience by making use of the newly developed Endoscopy Position Detecting Unit (UPD-3)by Olympus Optical Co, Ltd, Japan.

The investigators propose to conduct a prospective randomized controlled trial to compare the caecal intubation rate of colonoscopy being performed with and without UPD-3 guidance. Colonoscopies performed by endoscopists with different level of experience will be randomized to UPD-3 guided group or conventional group (no UPD-3 guidance). Patient controlled sedation (PCS) containing propofol and alfentanil will be given to all patients. The investigators hypothesize that UPD-3 guided colonoscopy is associated with high caecal intubation rate (complete colonoscopy), shorter time to caecum, less patient pain and lower sedative medication requirement. A high caecal intubation rate facilitates a reliable colonoscopy screening. Decreased colonic looping and shorter time to caecum may reduce patient discomfort during the procedure. It may also facilitate learning and acquiring the skill of colonoscopy in trainees.