Colonoscopy procedural skills and training for new beginners

Figure 1 Comparison between normal-type colonoscope and long-type colonoscope (A), components of a colonoscope (B), control section; lateral and forward view (C, D). WL: Working length.

Figure 2 Posture of examinee and examiner (endoscopist). A: Left lateral decubitus position of the examinee; B: Two-man method; C: One-man standing method; D: One-man sitting method.

Figure 3 Basic techniques. A: Up deflection; B: Down deflection; C: Left deflection; D: Right deflection; E: Push forward and pull back; F: Air insufflation (simple closure of hole in the air/water infusion button; pushing button not required); G: Example of air insufflation; H: Air suction (pushing the button above air/water infusion button); I: Example of water suction (because air is invisible).

Figure 4 Advanced techniques. A: Jiggling; B: Effect of jiggling; C: Shaking; D: Effect of shaking; E: Right turn shortening; F: Left turn shortening.

Figure 5 Auxiliary techniques. A: Left lateral decubitus position; B: Supine position change; C: Right lateral decubitus position change; D: Prone position change; E: Abdominal compression. Left upper corner: Hepatic flexure compression; Right upper corner: Sigmoid colon compression; Left lower corner: Transverse colon compression; Right lower corner: Sigmoidodescending junction compression.

Figure 6 Schematogram of large intestine. Red dotted circles (rectosigmoid junction, sigmoidodescending junction, splenic flexure, hepatic flexure) and green dotted box (sigmoid colon) are potential difficult segments during the procedure.

Figure 7 Procedure description. A: For example, detailed left lateral decubitus position (the examinee with knees bent and pulled up); B: Perianal lesion; C: Various anal lesions; D: Red-out sign; E: Anal canal and distal rectum (Retroflexion view); F: rectum; G: Rectosigmoid junction; H: Sigmoid colon; I: Sigmoidodescending junction; J: Descending colon with horizontal fluid; K: Descending colon (fluid-removal view); L: Splenic flexure and spot; M: Comparison of splenic and hepatic flexures (barium study view); N: Transverse colon; O: Hepatic flexure and spot; P: Hepatic flexure and spot (retroflexion view); Q: Ascending colon; R: Cecum and ileocecal valve; S: Cecal base and appendix orifice; T, U, V: Terminal ileum (water filling view, indigocarmine-dye view, narrow-band imaging view, respectively).

Figure 8 Suggested algorithm for structured learning and training of colonoscopy in new beginners. ¹Technical skills include methods for handling the colonoscope and resolving the loops, the ability to perform the colonoscopic examination adequately and in a reasonable amount of time; ²Cognitive skills include the indications and contraindications of the colonoscopic examination, the identification and classification of lesions, clinical decision-making based on findings, and adequate reporting of the colonoscopy; ³Examination-related skills include risk assessment of the patient and the safe method of administration of sedatives and/or analgesics. CIR: Cecal intubation rate; ADR: Adenoma detection rate.