CT of superior mesenteric artery syndrome
Authors:
Rodrigo Horstmann Castilhos; Mikael Häggström [notes 1]
Also known as Wilkie's syndrome, this condition occurs when the third part of the duodenum is compressed between the superior mesenteric artery and the aorta. Under normal conditions, there is retroperitoneal fat around the third part of the duodenum, which avoids compression by creating an aortomesenteric angle > 28º.
Planning
Indications
Imaging is indicated in the presence of risk factors of the condition:[1]
- Most common in females aged 10-39 years
- Previous accentuated weight loss
- Previous surgery for scoliosis
- Anatomical variations in the ligament of Treitz, with consequent elevation of the duodenum
- Signs and symptoms[1]
- Postprandial upper abdominal pain that is relieved in ventral or left lateral decubitus
- Nausea
- Emesis
- Weight loss
Choice of modality
- CT of superior mesenteric artery syndrome is generally the investigation of choice in adults.[2]
- Abdominal ultrasonography combined with endoscopy is preferred in children.[2]
Evaluation
Measure the following relations between the aorta and superior mesenteric artery:
- Aortomesenteric angle, where <25º indicates the condition[1]
- Aortomesenteric distance, where a distance <8 mm indicates the condition[1]
Also exclude:
- Compression of the left renal vein.[2]
- Portal venous pneumatosis[2]
- Abdominal aortic aneurysm,[2] see CT of abdominal aortic aneurysm.
Notes
- ↑ For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Radlines:Authorship for details.
References
- ↑ 1.0 1.1 1.2 1.3 Cardarelli Leite, Leandro et al. Abdominal vascular syndromes: characteristic imaging findings. Radiol Bras [online]. 2016, vol.49, n.4 [cited 2019-07-12], pp.257-263. Available from: <http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-39842016000400011&lng=en&nrm=iso>. ISSN 0100-3984. http://dx.doi.org/10.1590/0100-3984.2015.0136.
- ↑ 2.0 2.1 2.2 2.3 2.4 Frederick Merrill Karrer. Superior Mesenteric Artery (SMA) Syndrome Workup. Medscape. Updated: Dec 31, 2018