bubble_chart Overview

Superior Mesenteric Artery Compression Syndrome, also known as Wilkie's disease or compressive ileus, refers to a series of symptoms caused by partial or complete obstruction of the horizontal part of the duodenum due to compression by the superior mesenteric artery.

bubble_chart Pathogenesis

The anatomical characteristics of the duodenum, the superior mesenteric artery, and the abdominal aorta are closely related to the occurrence of this disease. Under normal circumstances, the duodenum is located within the angle formed by the abdominal aorta and its forward branch—the superior mesenteric artery. The front of the duodenum is the obliquely running superior mesenteric artery, while the back is the abdominal aorta and the spine. Through angiography, the normal angle in healthy individuals is 47-60°. When the mesentery is too long or too short, visceral ptosis, spinal anteversion, or variations in the superior mesenteric artery itself occur, the mesentery may pull downward, reducing the angle to often less than 6-25°, compressing the horizontal part of the duodenum, leading to intestinal narrowing and resulting in symptoms of duodenal obstruction.

bubble_chart Clinical Manifestations

This disease can occur at any age, but is more common in emaciated young and middle-aged women or those who are bedridden for long periods. It presents as a chronic intermittent illness, which can resolve on its own after several days, though acute onset is occasionally seen. The main clinical manifestations are those of duodenal obstruction, including postprandial epigastric fullness and pain, followed by nausea and vomiting, with a large volume of vomitus, similar to pyloric obstruction. A distinctive feature of this disease is that the symptoms are related to body position; symptoms worsen in the supine position due to posterior compression, while they are alleviated in the prone, knee-chest, or left lateral positions. Severe obstruction may be accompanied by dehydration and electrolyte imbalances. Patients with recurrent episodes may exhibit signs of malnutrition such as emaciation and anemia. Additionally, some patients may present with neurological Guanneng symptoms.

bubble_chart Auxiliary Examination

1. Intestinal X-ray contrast: In the stage of remission, no abnormalities are usually found. In the stage of attack, signs of duodenal compression can be observed, with a longitudinal knife-like obstruction or a waterfall-like descent at the center of the third segment (horizontal end). The passage of barium is slow and can remain in the duodenum for more than 6 hours. There is dilation of the proximal intestinal tract, which is related to changes in body position. 20% may be accompanied by gastric dilation.

2. Type B ultrasound examination: Some believe that timed ultrasound imaging has high diagnostic value and have proposed diagnostic criteria for this disease: ① After drinking water, the maximum width of the duodenal transverse segment during peristalsis is less than 10mm within the angle between the superior mesenteric artery pulse and the main artery pulse. ② Dilation of the descending duodenum, Neijing >30mm. ③ Type B ultrasound shows a "funnel-shaped" or "bottle gourd peel-shaped" image. ④ The angle between the main artery pulse and the superior mesenteric artery pulse is less than 13°.

bubble_chart Diagnosis

After intermittent fasting, symptoms such as abdominal distension and fullness, nausea, and vomiting are related to body position, worsening in the supine position and alleviating in the prone or lateral positions. Diagnosis is generally confirmed when X-ray imaging shows signs of compression at the horizontal segment of the duodenum, and B-ultrasound or angiography reveals a reduced angle between the superior mesenteric artery pulse and the abdominal aortic pulse.

bubble_chart Treatment Measures

Patients with mild symptoms should control their diet and rest in bed, preferably in a prone or lateral position. For those with significant nausea and vomiting, intravenous fluids and electrolytes should be supplemented. Most patients can gradually alleviate symptoms with symptomatic treatment. If internal medicine treatment is ineffective, a side-to-side duodenojejunostomy or Treitz ligament release can be performed, with satisfactory results.

bubble_chart Differentiation

Attention should be paid to differentiating from other diseases that cause duodenal stasis, such as duodenal tumors, stones, Chinese Taxillus Herb worms, and external compressions from other lesions (such as tumors and cysts).