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غرفة التنظير الداخليEndoscopy suite

Colonoscopy

Drive a colonoscope from the rectum to the caecum and into the terminal ileum, the way the examination is done: the patient on the left side, the scope's up toward the front of the body. Find the valves of Houston, retroflex to see the dentate line, take the sigmoid and the two flexures, and prove caecal intubation by the appendiceal orifice and the ileocaecal valve.

  • Bronchoscopy
  • Gastroscopy
  • Colonoscopy
  • Cystoscopy
  • Ventriculoscopy

Scope view

Preparing the organ…

Tip 0° up, 0° rightShaft turned 0°

↑ ↓ or scroll: advance and withdraw · drag or W A S D: bend the tip · Q E: turn the scope · Enter: go into the chosen orifice

Picture orientation

The picture is what the colonoscope sees, with its up mark at 12 o'clock. It goes in with its up toward the patient's front; looking up the colon toward the head, the patient's right is then on the left of the picture. The patient lies on the left side, so fluid pools on the left wall. Every loop and every turn of the shaft changes this, so read the rim letters.

The letters on the rim follow the scope as it turns: A anterior, P posterior, R and L the patient's right and left, S and I superior (toward the head) and inferior. An axis shows only while it lies across the picture; one running along the view fades out.

Map

Seen from the front, the patient's right on your left.

You are in

Labels are off: nothing in the picture is named, the breadcrumb is hidden and the map shows no scope until you find it.

Anatomy: BodyParts3D, © DBCLS, CC BY-SA 2.1 Japan — the lumen, its centreline and its landmarks built for this trainer. The lighting, the mucosa and its patterns are drawn, not photographed. Also drawn rather than measured:

  • The sigmoid colon is missing from BodyParts3D 4.0: it is drawn as an S-shaped loop of about 12 cm in the pelvis, from the top of the rectum to the lower descending colon, kept short so the depths read as with a straightened scope (rectosigmoid about 14 cm, splenic flexure 45, hepatic flexure 62, caecum 81).
  • The wall is drawn as an insufflated tube of the usual calibre (rectal ampulla about 6 cm across, colon 4–5 cm) along BodyParts3D's course, its tightest bends rounded; BodyParts3D's own shells are narrower and uninflated.
  • Haustral folds are drawn as crescents every 2.5–3.5 cm, interrupted by three taeniae coli 120° apart; in the transverse colon they are drawn as chords, which makes the triangular lumen.
  • The three valves of Houston are drawn as semilunar shelves at about 7, 9.5 and 12 cm from the anal verge, on the left, right and left walls.
  • The caecal pouch is deepened to about 5 cm below the ileocaecal valve; the valve's lips, the appendiceal orifice and the three converging taeniae (the trifold) are drawn.
  • The terminal ileum is a drawn tube of about 5 cm leaving the valve medially; BodyParts3D's ileum lies collapsed against the caecum.
  • The anal canal is only a short closed funnel below the start, so that a retroflexed view has an anorectal junction and a dentate line to find; nothing outside the body is modelled.
  • The colours are painted: pink-orange colonic mucosa, the blue-grey shadow of the liver at the hepatic flexure, the yellowish ileocaecal valve, the paler ileum.