Practical Gastrointestinal Endoscopy

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CHAPTER 6
Fig. 6.83–Transillumination
deep in the iliac fossa suggests
the cecum.
Fig. 6.84–Finger pressure in
the right iliac fossa indents the
cecum.
become effective. Aspirate, and steer carefully down the center
of the deflating lumen, then push the last few centimeters into
the cecum. If it proves difficult to reach the last few centimeters
to the cecal pole, change the patient’s position to prone (even a
partial position change of 20–30° may help) or, if that does not
work, change to supine position. Once in the cecum, the bowel
can be reinflated to get a view.
The cecum can be voluminous with pronounced haustral in-foldings
and tendency to spasm making it confusing to examine. In
particular, it is possible to be mistaken about whether the pole
has actually been reached. One catch is that the ileo-cecal valve
fold, the major circumferential fold at the junction of the ascending
colon and the cecum—on which is situated the giveaway
bulge of the valve—has a tendency to be in tonic spasm. The
contracted fold may easily be mistaken by the unwary either
for the appendix orifice or for the ileo-cecal valve. Insufflating
and pushing in with the instrument tip and/or using extra intravenous
antispasmodic medication will reveal the cavernous
cecal pole beyond.
Be careful to identify landmarks before assuming ‘total colonoscopy’
has been performed. The appendix orifice or ileo-cecal valve should
be identified as landmarks, with or without imaging; also use
right iliac fossa transillumination (Fig. 6.83) or finger palpation
indenting the cecal region (Fig. 6.84) to confirm location of the
tip. At the same time the colonoscope should, after withdrawal,
be at 70–80·cm. The cecal pole is often difficult to examine, is not
always completely clean and is sometimes in tonic spasm; a ‘too
good to be true’ appearance may therefore actually be only the
ascending colon or even the hepatic flexure. Inability to locate
the ileo-cecal valve opening and noting that the shaft distance on
withdrawal is only at 60–70 ·cm should warn of this possibility.
Finding the ileo-cecal valve
The ‘appendix trick’ or ‘bow and arrow’ sign is an ingenious way
of finding the ileo-cecal valve—and simultaneously entering
it too—a ‘double whammy’ when it works first time, as it often
does!
1–Find the appendix orifice.
2–Imagine an arrow pointing in the direction of the appendix
lumen (Fig. 6.85a)
3–Angulate in that direction and pull back (still angled) for
about 3–4·cm.
4–At this point expect the proximal lip of the ileo-cecal valve
to start to ride up over the lens, with shiny bumps of close-up
ileal villi apparent, rather than the mirror-smooth crypt-spotted
colon mucosa. (Fig. 6.85b).
5–Slow completely, insufflate and twist or angle gently to
wangle into the ileum.