Risk Factors Associated With Incomplete Colonoscopy Based on the Analysis of Computed Tomographic Colonography Findings:

Three-dimensional reconstruction of computed tomography colonography discloses anatomic features associated with colonoscopy failure

Objectives:

Three-dimensional virtual reality (3D VR) permits precise reconstruction of computed tomography (CT) images, and these allow precise measurements of colonic anatomical parameters. Colonoscopy proves challenging in a subset of patients, and thus CT colonoscopy (CTC) is often required to visualize the entire colon. The aim of the study was to determine whether 3D reconstructions of the colon could help identify and quantify the key anatomical features leading to colonoscopy failure.

Design:

Retrospective observational study.

Methods:

Using 3D VR technology, we reconstructed and compared the length of various colonic segments and number of bends and colonic width in 10 cases of CTC in technically failed prior colonoscopies to 10 cases of CTC performed for non-technically failure indications.

Results:

We found significant elongation of the sigmoid colon (71 ± 23 cm versus 35 ± 9; p = 0.01) and of pancolonic length (216 ± 38 cm versus 158 ± 20 cm; p = 0.001) in cases of technically failed colonoscopy. There was also a significant increase in the number of colonic angles (17.7 ± 3.2 versus 12.7 ± 2.4; p = 0.008) in failed colonoscopy cases.

Conclusion:

Increased sigmoid and pancolonic length and more colonic bends are novel factors associated with technical failure of colonoscopy.

TEACHING BASIC COLONOSCOPY SKILLS: QUALITY AND SAFETY STANDARDS CAN BE FULFILLED IN AN OUTPATIENT UNIVERSITY CENTER

BACKGROUND

Recent studies have shown that endoscopy fellows can perform colonoscopy effectively and safely. However, little is known about the performance of surgical residents without prior knowledge of endoscopic techniques.

OBJECTIVE

To assess whether quality indicators were met at an outpatient endoscopy center and whether surgical residents, without prior upper or lower endoscopy skills, could perform colonoscopy adequately.

METHODS

A prospective non-randomized cohort study was undertaken. All exams were performed either by assistant physicians or by residents. Quality measures were compared between those groups.

RESULTS

A total of 2720 colonoscopies were analyzed. In the resident group, we observed older patients (57.7±12.7 years vs 51.5±14.5 years, P<0.001), a higher prevalence of screening colonoscopies (52% vs 39.4%, P<0.001) and a higher prevalence of colorectal cancer (6.4% vs 1.8%, P<0.001). The cecal intubation rate was higher in the attending group (99.9% vs 89.3%; P<0.001). The polyp detection rate was 40.8%, and no differences were observed between the studied groups. The residents had a higher rate of perforation in all exams (0.4% vs 0%; P=0.02). Postpolypectomy bleeding and 7-day readmission rates were the same (0.2%). All readmissions in 7 days occurred due to low digestive bleeding, and none required intervention.

CONCLUSION

Quality indicators were met at a university outpatient endoscopy center; however, medical residents achieved lower rates of cecal intubation and higher rates of perforation than the attending physicians.