Radiology Quiz
Case history
After routine blood tests had been taken this
69 year old woman was found to have microcytic, hypochromic anaemia. Her general
practitioner could not find any obvious cause
and asked for further investigations.
Questions
(1) What procedure has this patient undergone and what radiological abnormalities can you identify?
(2) Estimate the relative dose of radiation from this radiological procedure compared with a posterior-anterior chest radiograph.
(3) What are the potential complications of the benign pathology seen on the film?
(4) If you suspected that this patient had a perforated bowel how would your radiological approach change? On further questioning by the consultant physician the patient admitted to otherwise unidentified symptoms of altered bowel habit and some pain in the abdomen, especially in the left iliac fossa.
(5) Given the findings seen on the radiograph what else might you consider doing?
Abdominal xray of a 69 year old woman with microcytic, hypochromic anaemia
Answers
(1) A double contrast barium enema has
been carried out. This means that a mixture of barium (a radio-opaque contrast
agent) and air has been used. This provides a better image of the fine detail of
the bowel mucosa.
There are two main radiological abnormalities. A bowel stricture can be seen
just proximal to the rectosigmoid junction. There is "shouldering" of this lesion
with loss of the normal mucosal detail. There is also an abrupt change from normal to abnormal mucosa, which suggests
a neoplastic stricture. There are also multiple diverticula in the sigmoid colon.
Ninety per cent of diverticular disease is
identified incidentally, as it is frequently
asymptomatic in nature.
(2) A barium enema has the same radiation
dose as 350 posterior-anterior chest radiograms. This is equivalent to three years
of background radiation. You should be
aware of radiation doses when ordering
radiological procedures.
(3) The diverticular disease is the benign disease in this case, but several complications
may occur. These include haemorrhage,
abscess formation, fistula formation (with
neighbouring bowel, vagina, or bladder),
large bowel obstruction (caused by fibrotic stricturing), and bowel perforation.
(4) Administering barium is dangerous in
cases of perforation as it may leak from
the bowel - for example, perforated diverticulum - into the peritoneum. A water soluble agent, such as astrografin, will be
required as this is safe and allows the
bowel to be seen.
(5) You should be concerned in a patient of
this age to rule out any malignancy of the
bowel. Altered bowel habit and abdominal pain are shared symptoms of diverticular disease and colorectal carcinoma,
both of which often present in elderly
people. Furthermore, as this barium
enema illustrates, multiple diverticula in
the sigmoid colon may make it difficult to
interpret whether any concurrent pathology is present. It would be wise to undertake appropriate flexible bowel endoscopy
to rule out any malignancy.
Diverticular disease and colorectal
carcinoma can coexist as this film readily
illustrates with diverticular disease masking
fine mucosal detail.
Key
- Colonic diverticulum: a pouch or sac of
bowel mucosa that has caused a hernia
through a weakened part of the muscular
wall of the colon at the point of least
resistance.
- Diverticular disease: a condition in which
there are diverticula in the colon. It is a
loose term to cover both diverticulosis
(the existence of diverticula) and
diverticulitis (inflammation of the
diverticula).
- Stricture: a narrowing of any tubular
structure-for example, the bowel-in the
body.
Barry Kelly, consultant radiologist, Royal Victoria Hospital, Belfast
Ian C Bickle, fourth year medical student, Queen's University, Belfast
studentBMJ 2001;09:43-84 March ISSN 0966-6494
