Type:
Educational Exhibit
Keywords:
Emergency, Abdomen, Gastrointestinal tract, CT, Diagnostic procedure, Education, Obstruction / Occlusion
Authors:
L. Aguilar Sánchez1, M. D. M. García Gallardo1, E. Carmona González2; 1MÁLAGA/ES, 2Osuna/ES
DOI:
10.26044/ecr2019/C-1318
Findings and procedure details
MDCT is a very useful diagnostic tool since clinical and laboratory findings are similar for bezoars and other causes of small-bowel obstruction.
It is superior to any other imaging technique for the differential diagnosis between those entities,
as well as to determine the degree of obstruction and complications.
MDCT allows evaluation of:
- Location of bezoar and transition point.
- Visualization of a gastric lesion with characteristics similar to the intestinal lesion.
- Size,
length,
and morphology of the lesion.
- Presence of "wall / capsule"
- Presence of floating fat density material dispersed in proximal bowel loops.
- Degree of obstruction.
- Intraperitoneal fluid.
Characteristically,
bezoars appear on CT as a well-defined heterogeneous and mottled intraluminal mass with interposed air bubbles,
proximal to the zone of intestinal caliber change together with a peripheral capsule and associated in some cases to a gastric lesion with similar radiological features.
Fig. 1
However,
some of these findings are similar to those seen in intestinal obstructions of other causes,
especially when they develop progressively,
in what is referred to as the " small-bowel faeces sign" Fig. 3 ,
Fig. 5 Fig. 7
This sign was described for the first time in 1995 by Mayo-Smith and it is mainly seen when the obstruction develops slowly and progressively due to decreased transit and absorption and increase in secretion.
Distinction between both is clinically important because small-bowel faeces sign is often present in obstructions secondary to adhesions whose initial treatment is conservative in most cases,
while bezoar will require surgery.
HOW TO DIFFERENTIATE BEZOAR FROM SMALL BOWEL FAECES SIGN
- Ovoid or round shape of Bezoars.
Fig. 1 ,
Fig. 2 ,
Fig. 4 ,
Fig. 6
- Bezoars usually have well-defined margins,
with presence of hyperdense peripheral wall or capsule,
a finding absent in "small-bowel faeces sign".
- Presence of a gastric mass with similar features (intraluminal mottled image with well-defined contours,
air bubbles and areas of fat density).
Fig. 2 ,
Fig. 6 .
Use of lung window is recommended for better visualization.
Fig. 1.
- Size less than 10 cm in Bezoars,
while "Small-bowel faeces" sign associated with obstructive symptoms usually have longer lengths.
Fig. 3 ,
Fig. 5 ,
Fig. 7 .
- A higher degree of obstruction is commonly associated with phytobezoars.
- "Floating fat-density residues" sign favours the diagnosis of Bezoar.
It corresponds to the presence of fat-density images floating in the dilated intestinal loops proximal to the obstructive lesion.
Fig. 2 ,
Fig. 4
In our opinion,
classic signs such as the detection of fat density (range between -50 and -150) in the interior of the bezoar and observing the lesion just at the transition point,
do not help in the differential diagnosis since they are generally found in both entities.