Tic Tac Toe
Since the 1980s, people
suffering from intestinal
complaints such as
constipation have sometimes
been given a handful of plastic
pellets containing barium (radiopaque
markers) to help diagnose their problem
using X-ray diagnostics, explains Dr
Luca Marciani, University of Nottingham
associate professor in gastrointestinal
MRI (pictured, with patient Jed Randall).
These tests can provide some objective
evidence, as opposed to the patient
reporting their toilet stops – or a parent
doing it for the child. “There are various
facets of this, from the more normal gut
transit with symptoms of pain to slowtransit
constipation, to retention and
obstruction,” Marciani points out. In
X-rays, the heavy element barium shows
up as opaque in an X-ray scan, so the
pellets’ progress or lack of progress in
the bowel can indicate what factors might
be causing the problem. Bunching at the
top of the bowel indicates severely slow
transit; piling up at the bottom suggests
function. A missing group of pellets
suggests a bowel movement has occurred.
But the test is not ideal for children.
First, it involves exposing them to ionizing
radiation, large doses of which are bad
for developing organs and can cause
problems in later life. Second, the X-ray
image itself is dif cult to interpret, as
internal organs tend to come out fuzzy,
and the bowel curls around the abdominal
cavity in complex way, he adds.
Still, a test was needed to help
clinicians diagnose the causes of
childhood constipation, to nd the right
treatment. The condition peaks
in school-age children, some
14% of whom suffer from it
at some point. And as many
as 30,000 in England per year
end up in hospital as a result,
according to government gures.
Much better results -- without
the health risks -- are to be found
from more recent technology,
particularly the MRI, magnetic resonance
imaging, technologies of which were
software module).
The way in which MRI
acquires images of the body
differs from the way that X-rays
do, so the two technologies’
images look very different. In particular,
plastic pellets don’t stand out; but
oil-water emulsions do.
So the idea was a capsule containing
a medically-safe fat emulsion. Drug
capsules are a great way to carry material
into the body, but they are designed to
disintegrate; the gastrointestinal transit
test process requires something hard
enough to resist stomach acid and bowel
water for a few days of transit. Also, the
size of the capsule would need to be
adapted to suit children, whose smaller
throats make it dif cult to swallow fullsized
tablets.
His vision of the way the test would
work is to provide a patient with 24
minicapsules a day for three days
A new improvement of an old method of diagnosing intestinal
problems has relied on a novel manufacturing process to
produce a new kind of tracker bead
a retention problem; being spread around
implies more normal
invented by Nottingham
University physicist Prof
Sir Peter Mans eld in the
1970s. MRI scans can
be stitched together
into 3D images. (A
further goal of the
project, down the
line, is to develop
add-on software
to automatically
analyse the images;
specialist rm
Motilent designed
an initial analysis
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