Meckel's diverticulum other imaging findings: Difference between revisions
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** European Association for Nuclear Medicine (EANM) | ** European Association for Nuclear Medicine (EANM) | ||
* [[Technetium-99m|Technetium-99m pertechnetate scanning]] helps in the detection of a symptomatic [[bleeding]] Meckel’s diverticulum. | * [[Technetium-99m|Technetium-99m pertechnetate scanning]] helps in the detection of a symptomatic [[bleeding]] Meckel’s diverticulum. | ||
* It is preferred as the investigation of choice for the diagnosis of Meckel's diverticula in children due to the following features: | * It is preferred as the investigation of choice for the diagnosis of Meckel's diverticula in children due to the following features:<ref name="urlFundamentals of Pediatric Surgery - Google Books">{{cite web |url=https://books.google.com/books?id=-AAD9WiIZLAC&pg=PA773&lpg=PA773&dq=Mattei,+P.+(2011).+Fundamentals+of+Pediatric+Surgery.+New+York,+NY:+Springer+Science%2BBusiness+Media,+LLC.&source=bl&ots=VWeSV7HsOo&sig=p2LET6NVySpB-ANSdF3G1YmAzw8&hl=en&sa=X&ved=0ahUKEwip4uPoya3YAhUG_IMKHUn8ABIQ6AEIQTAD#v=onepage&q=Mattei%2C%20P.%20(2011).%20Fundamentals%20of%20Pediatric%20Surgery.%20New%20York%2C%20NY%3A%20Springer%20Science%2BBusiness%20Media%2C%20LLC.&f=false |title=Fundamentals of Pediatric Surgery - Google Books |format= |work= |accessdate=}}</ref> | ||
** High accuracy | ** High accuracy | ||
** [[Non-invasive (medical)|Noninvasive]] nature | ** [[Non-invasive (medical)|Noninvasive]] nature | ||
** 95% [[Specificity (tests)|specificity]] | ** 95% [[Specificity (tests)|specificity]] | ||
** 85% [[Sensitivity (tests)|sensitivity]] | ** 85% [[Sensitivity (tests)|sensitivity]] | ||
** Approximately 50% of symptomatic Meckel's diverticula have [[Ectopia|ectopic]] [[Stomach|gastric]] or [[Pancreas|pancreatic cells]] contained within them | ** Approximately 50% of symptomatic Meckel's diverticula have [[Ectopia|ectopic]] [[Stomach|gastric]] or [[Pancreas|pancreatic cells]] contained within them<ref name="pmid10706156">{{cite journal |vauthors=Martin JP, Connor PD, Charles K |title=Meckel's diverticulum |journal=Am Fam Physician |volume=61 |issue=4 |pages=1037–42, 1044 |year=2000 |pmid=10706156 |doi= |url=}}</ref> | ||
* [[Technetium-99m|Technetium-99m pertechnetate scanning]] is not preferred in adults as [[Type I and type II errors|false negative]] rates are high with [[Specificity (tests)|specificity]] of 9% and [[Sensitivity (tests)|sensitivity]] of 62%. | * [[Technetium-99m|Technetium-99m pertechnetate scanning]] is not preferred in adults as [[Type I and type II errors|false negative]] rates are high with [[Specificity (tests)|specificity]] of 9% and [[Sensitivity (tests)|sensitivity]] of 62%. | ||
* [[Type I and type II errors|False-positives]] are seen in the following conditions: | * [[Type I and type II errors|False-positives]] are seen in the following conditions: | ||
Revision as of 20:49, 28 December 2017
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Meckel's diverticulum Microchapters |
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Meckel's diverticulum other imaging findings On the Web |
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Risk calculators and risk factors for Meckel's diverticulum other imaging findings |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Sudarshana Datta, MD [2]
Overview
A technetium-99m (99mTc) pertechnetate scan is the investigation of choice for the diagnosis of Meckel's diverticulum. This scan detects gastric mucosa; since approximately 50% of symptomatic Meckel's diverticula have ectopic gastric (stomach) cells contained within them. A Meckel's diverticulum containing gastric mucosa manifests as a small rounded area of increased activity in the right lower quadrant, while normal activity simultaneously appears in the stomach.
Other Imaging Findings
Technetium-99m pertechnetate radioisotope scanning
- September 2014: Guidelines for the Scintigraphy for Meckel’s diverticulum were laid down by:[1]
- Society of Nuclear Medicine and Molecular Imaging (SNMMI)
- European Association for Nuclear Medicine (EANM)
- Technetium-99m pertechnetate scanning helps in the detection of a symptomatic bleeding Meckel’s diverticulum.
- It is preferred as the investigation of choice for the diagnosis of Meckel's diverticula in children due to the following features:[2]
- High accuracy
- Noninvasive nature
- 95% specificity
- 85% sensitivity
- Approximately 50% of symptomatic Meckel's diverticula have ectopic gastric or pancreatic cells contained within them[3]
- Technetium-99m pertechnetate scanning is not preferred in adults as false negative rates are high with specificity of 9% and sensitivity of 62%.
- False-positives are seen in the following conditions:
- Intussusception
- Volvulus
- Obstruction of the small intestine
- Acute appendicitis
- Carcinoid of the appendix
- Carcinoma of the cecum
- On intravenous administration, the Technetium-99m pertechnate radioisotope is taken up by the gastric mucosa.
- In order to obtain a positive result, atleast 1.8 cm2 of ectopic gastric mucosa in Meckel's diverticulum is required.
- A Meckel's diverticulum containing gastric mucosa manifests as a small rounded area of increased activity in the right lower quadrant.
- Normal activity simultaneously appears in the stomach.
- Technetium-99m pertechnetate scanning requires 30 images, taken at 1-minute intervals to demonstrate terminal ileum activity.
- The use of Pentagastrin in Technetium-99m pertechnetate scanning has a synergistic effect:
- Role of Pentagastrin:
- Histamine-2 (H2) receptor blocker
- Enhances radioisotope uptake by the cells:
- Promotes isotope retention
- Blocks intraluminal release of isotope
- Minimizes false negative results
- Meckel's diverticulum is identified as a saccular, blind-ending structure located on the antimesenteric border of the ileum.
- Meckel's diverticulum is usually found in the right lower quadrant and pelvic region.
- The junction of the diverticulum with the ileum may show a mucosal triangular plateau or triradiate fold pattern (represents the site of omphalomesenteric duct attachment to the ileum).
Angiography
- Angiography may assist in determining the location and severity of bleeding in case of a bleeding Meckel's diverticulum.
- In patients presenting with acute GI bleeding, superior mesenteric angiography is effective if blood loss exceeds 0.5 mL/min(brisk bleeding).
References
- ↑ Spottswood SE, Pfluger T, Bartold SP, Brandon D, Burchell N, Delbeke D, Fink-Bennett DM, Hodges PK, Jolles PR, Lassmann M, Maurer AH, Seabold JE, Stabin MG, Treves ST, Vlajkovic M (2014). "SNMMI and EANM practice guideline for meckel diverticulum scintigraphy 2.0". J Nucl Med Technol. 42 (3): 163–9. doi:10.2967/jnmt.113.136242. PMID 24948825.
- ↑ "Fundamentals of Pediatric Surgery - Google Books".
- ↑ Martin JP, Connor PD, Charles K (2000). "Meckel's diverticulum". Am Fam Physician. 61 (4): 1037–42, 1044. PMID 10706156.