Book contents
- Frontmatter
- Contents
- Preface
- Acknowledgements
- Section 1 Diaphragm and adjacent structures
- Section 2 Liver
- Section 3 Biliary system
- Section 4 Spleen
- Section 5 Pancreas
- Section 6 Adrenal glands
- Section 7 Kidneys
- Section 8 Retroperitoneum
- Section 9 Gastrointestinal tract
- Case 54 Gastric antral wall thickening
- Case 55 Pseudoabscess due to excluded stomach after gastric bypass
- Case 56 Strangulated bowel obstruction
- Case 57 Transient ischemia of the bowel
- Case 58 Angioedema of the bowel
- Case 59 Small bowel intramural hemorrhage
- Case 60 Pseudopneumatosis
- Case 61 Meckel's diverticulitis
- Case 62 Small bowel intussusception
- Case 63 Pseudoappendicitis
- Case 64 Portal hypertensive colonic wall thickening
- Case 65 Pseudotumor due to undistended bowel
- Case 66 Gastrointestinal pseudolesions due to oral contrast mixing artifact
- Case 67 Perforated colon cancer mimicking diverticulitis
- Section 10 Peritoneal cavity
- Section 11 Ovaries
- Section 12 Uterus and vagina
- Section 13 Bladder
- Section 14 Pelvic soft tissues
- Section 15 Groin
- Section 16 Bone
- Index
- References
Case 66 - Gastrointestinal pseudolesions due to oral contrast mixing artifact
from Section 9 - Gastrointestinal tract
Published online by Cambridge University Press: 05 November 2011
- Frontmatter
- Contents
- Preface
- Acknowledgements
- Section 1 Diaphragm and adjacent structures
- Section 2 Liver
- Section 3 Biliary system
- Section 4 Spleen
- Section 5 Pancreas
- Section 6 Adrenal glands
- Section 7 Kidneys
- Section 8 Retroperitoneum
- Section 9 Gastrointestinal tract
- Case 54 Gastric antral wall thickening
- Case 55 Pseudoabscess due to excluded stomach after gastric bypass
- Case 56 Strangulated bowel obstruction
- Case 57 Transient ischemia of the bowel
- Case 58 Angioedema of the bowel
- Case 59 Small bowel intramural hemorrhage
- Case 60 Pseudopneumatosis
- Case 61 Meckel's diverticulitis
- Case 62 Small bowel intussusception
- Case 63 Pseudoappendicitis
- Case 64 Portal hypertensive colonic wall thickening
- Case 65 Pseudotumor due to undistended bowel
- Case 66 Gastrointestinal pseudolesions due to oral contrast mixing artifact
- Case 67 Perforated colon cancer mimicking diverticulitis
- Section 10 Peritoneal cavity
- Section 11 Ovaries
- Section 12 Uterus and vagina
- Section 13 Bladder
- Section 14 Pelvic soft tissues
- Section 15 Groin
- Section 16 Bone
- Index
- References
Summary
Imaging description
Incomplete mixing of oral contrast and bowel content may create a spurious appearance of an intraluminal mass or bowel wall thickening at CT (Figures 66.1–66.4).
Importance
A false positive diagnosis of bowel pathology may lead to unnecessary testing and anxiety.
Typical clinical scenario
While the potential for incomplete mixing of positive oral content with gastrointestinal content to create pseudolesions has been described in the stomach [1], I have encountered this pitfall most commonly in the right colon, likely due to the entry of liquid positive oral contrast from the terminal ileum into the semi-viscous content in the large bowel.
Differential diagnosis
Artifactual masses or wall thickening due to oral contrast mixing artifact can usually be recognized by the presence of air bubbles within the apparently thickened wall (Figures 66.3 and 66.4), or by failure of the abnormalities to extend onto the non-dependent portion of the bowel wall (Figure 66.2). Occasionally, follow-up imaging (Figure 66.1) or other testing may be required to confirm the absence of pathology.
Teaching point
An apparent mass or wall thickening in the gastrointestinal tract of a patient who has received positive oral contrast, especially if seen in the cecum or right colon, should be examined carefully for the possibility of a pseudolesion due to incomplete mixing of oral contrast and bowel content.
- Type
- Chapter
- Information
- Pearls and Pitfalls in Abdominal ImagingPseudotumors, Variants and Other Difficult Diagnoses, pp. 224 - 227Publisher: Cambridge University PressPrint publication year: 2010