What is SMA syndrome?
SMA syndrome is a condition secondary to compression of the third portion of the duodenum between the abdominal aorta and the SMA. Patients may present with abdominal pain, early satiety, nausea, and vomiting. This is a rare condition which typically occurs in people who have rapidly lost weight, such as in patients hospitalized with burns or who suffer from anorexia nervosa, and most commonly affects young women.
The normal aortomesenteric distance (AMD) between the abdominal aorta and SMA is 10 to 28 mm. The normal aortomesenteric angle (AMA) between the abdominal aorta and SMA is 25° to 60°. Compression of the duodenum is typically seen when the AMD is ≤ 8 mm and when the AMA is ≤ 22°. Upstream dilation of the proximal duodenum and stomach is also typically seen in this condition.
