Superior mesenteric artery syndrome: Diagnosis and management

Abstract

Superior mesenteric artery (SMA) syndrome (also known as Wilkie's syndrome, cast syndrome, or aorto-mesenteric compass syndrome) is an obstruction of the duodenum caused by extrinsic compression between the SMA and the aorta. The median age of patients is 23 years old (range 0-91 years old) and predominant in females over males with a ratio of 3:2. The symptoms are variable, consisting of postprandial abdominal pain, nausea and vomiting, early satiety, anorexia, and weight loss and can mimic anorexia nervosa or functional dyspepsia. Because recurrent vomiting leads to aspiration pneumonia or respiratory depression via metabolic alkalosis, early diagnosis is required. The useful diagnostic modalities are computed tomography as a standard tool and ultrasonography, which has advantages in safety and capability of real-time assessments of SMA mobility and duodenum passage. The initial treatment is usually conservative, including postural change, gastroduodenal decompression, and nutrient management (success rates: 70%-80%). If conservative therapy fails, surgical treatment (i.e., laparoscopic duodenojejunostomy) is recommended (success rates: 80%-100%).

Keywords: Aorto-mesenteric compass syndrome; Cast syndrome; Superior mesenteric artery syndrome; Wilkie’s syndrome.

Figure 1

Anatomy related to superior mesenteric artery syndrome. SMA: Superior mesenteric artery.

Figure 2

Published patient age. Dot indicates an individual case. The data is based on our review. IQR: Interquartile range.

Figure 3

Upper gastrointestinal series (barium X-ray) of a 16-year-old male with superior mesenteric artery syndrome. Arrow indicates obstructive compression of the third portion of the duodenum.

Figure 4

Enhanced computed tomography images of a 56-year-old female with superior mesenteric artery syndrome. A: Coronal view; B: Axial view; C: Sagittal view. Computed tomography images show a markedly distended stomach and proximal duodenum by extrinsic compression between the superior mesenteric artery (arrow in panel B) and aorta.

Figure 5

Abdominal ultrasonographic images of a 53-year-old female with superior mesenteric artery syndrome. A and B: Upper abdominal ultrasonography shows a markedly dilated stomach (A) and obstruction of duodenum (B, which looks like beak, beak sign) by extrinsic compression between the superior mesenteric artery (SMA) and aorta (Ao); C: The SMA-Ao angle (7.5 degree) and distance (5 mm) are decreased. SMA: Superior mesenteric artery; Ao: Aorta.

Figure 6

Endoscopic findings of patients with superior mesenteric artery syndrome. A and B: Esophagitis (A) and gastric ulcer (B) with retained luminal contents; C: compression area in the third portion of the duodenum.