Type:
Educational Exhibit
Keywords:
Abdomen, Biliary Tract / Gallbladder, Gastrointestinal tract, Conventional radiography, CT, Ultrasound, Diagnostic procedure, Education, Education and training, Calcifications / Calculi
Authors:
T. Martínez Fernández1, L. Hernandez Munoz2, D. Soliva Martínez3, I. Belda Gonzalez4, M. E. Blanco López1, S. Relanzón Molinero1, M. A. Pérez Gil1, P. Fernández Iglesias1, J. A. Martínez Yunta1; 1Cuenca/ES, 2MADRID/ES, 3Tarancón/ES, 4Jódar/ES
DOI:
10.1594/ecr2013/C-1385
Imaging findings OR Procedure details
Gallstone ileus is an entity of complex diagnosis.
A better understanding of this condition allows a more precise diagnosis and early treatment,
essential in these patients.
Thus it is important to know the main radiological findings in the different imaging techniques (plain radiography,
ultrasound and CT).
Plain abdominal films
Findings suspicious of a gallstone ileus are:
Demonstration of the classic Rigler’s triad (Figure 1),
pathognomonic of gallstone ileus [7,
9] (two of our five patients).
It is characterized by:
- Air in the biliary tree (pneumobilia) and/or gallbladder (29-69%) [1,4-6,10] (Figure 5 A)
- Signs of partial or complete bowel obstruction (usually the small intestine) (53-86%) [5,6,10] (Figure 5A)
- Visualization of an ectopic gallstone (25-35%) [5,6,10].
Less than 15% of gallstones are visible [1,4] due to their radiolucency or because intestinal gas or bony structures may obscure them.
The triad is present in less than 15% of cases [5,7].
However, only 2 signs (present up to 40-50% of patients) may be enough to point out the diagnosis of the disease [4,
6,
8].
Abdominal Ultrasound
Ultrasonography can demonstrate the biliary-enteric fistula,
residual cholelithiasis,
choledocholithiasis and cholecystitis.
It can also visualize pneumobilia and/or air in the gallbladder (Figure 2A),
dilated bowel loops (Figures 2B,
3A) and ectopic gallstones (Figure 3A).
MDCT scanners
Newer MDCT scanners,
using multiplanar or 3D volume-rendering reconstructions,
have proved their effectiveness in the detection and evaluation of this entity,
with a sensitivity of 93% and specificity of 100% [10].
This technique can demonstrate pneumobilia and/or gas in the gallbladder (Figures 3B,
4A,
5B),
dilated bowel loops (Figure 4B) and ectopic gallstones (Figure 7 A),
and also provide information about :
- Direct visualization of biliary-enteric fistulae (Figures 6A,
6B).
- Number,
localization,
morphology and size of stones (Figure 7A).
- Signs of probable complication: free fluid,
ectopic extraintestinal gas,
gas in portal vein or pneumatosis intestinalis.