Early Satiety, Nausea, and Vomiting After Meals: Case Presentation

A 55-year-old woman presents to the surgical clinic with early satiety, nausea, and vomiting of partially digested food. These symptoms have been increasing over the past 2 years and substantially worsened over the past 3 months. The patient also reports epigastric fullness, especially after meals, which improves after vomiting. The woman has a slightly distended abdomen on examination. She is sent for an upright abdominal radiograph (shown). What is the suspicious finding on this radiograph?

Image from Radiopaedia.org, courtesy of Dr. Hani Alsalam.

Answer: “Double bubble” sign

The “double bubble” sign—recognized as dilation of both stomach and proximal duodenum—can indicate a partial duodenal obstruction. Causes of the double bubble sign are shown. The patient’s weight is 134 lbs; height is 67 inches. All vital signs are within normal limits. The patient denies rapid weight loss, fever, or change in bowel habits. Her medical history is remarkable for scleroderma, dysphagia due to esophageal stricture, Raynaud syndrome, congestive heart failure, and degenerative joint disease.

The patient is sent for a an upper GI series (shown), which reveals distention of the stomach (S) as well as the first and second part of duodenum (D). Only a small amount of contrast passed through the rest of the duodenum and proximal jejunum, which is suggestive of obstruction at level of second part of duodenum. What study may help to exclude mechanical causes of duodenal obstruction?
A. Upright abdominal radiograph
B. Abdominal pelvic computerized tomography scan
C. Esophagogastroduodenoscopy
D. Colonoscopy
E. Abdominal ultrasound

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Answer: C. Esophagogastroduodenoscopy

Esophagogastroduodenoscopy (EGD) is performed. A dilated second portion of the duodenum extending approximately 10 cm distal to the pylorus was found, filled with partially digested food. Erosive gastritis (arrow) and esophageal stricture were also identified. What additional imaging studies may be needed?

A contrast-enhanced computerized tomography (CT) scan of the abdomen and pelvis is performed, revealing a dilated stomach (S) and proximal duodenum (D). What other abnormality can be identified?

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Answer: A compressed third part of the duodenum, measuring approximately 4 mm across (blue arrow), is shown between the superior mesenteric artery (SMA) and aorta (Ao). Based on these studies, what is the patient’s diagnosis?
A. Gastric outlet obstruction
B. Chronic idiopathic intestinal pseudo-obstruction
C. Superior mesenteric artery syndrome
D. Large-bowel obstruction
E. Mesenteric ischemia

Image from Radiopaedia.org, courtesy of Dr. Yuranga Weerakkody and Dr. Erik Ranschaert.

Answer: C. Superior mesenteric artery syndrome

Superior mesenteric artery syndrome (Wilkie syndrome) is a rare but well-recognized vascular compression disorder. The condition is characterized by a decrease in the angle of the SMA in relationship to the aorta, resulting in compression of the third part of the duodenum between the SMA and the aorta, thus leading to obstruction. SMA syndrome results in chronic, intermittent, or acute complete or partial duodenal obstruction.^[1,2]

Image from Radiopaedia.org, courtesy of Dr. Charudutt Jayant Sambhaji.

This abdominal and pelvic CT scan shows duodenal compression (black arrow) by the SMA (red arrow) and the aorta (blue arrow). What are the possible causes of SMA syndrome?

Image from Wikipedia Commons, courtesy of Samantha S. Mina.

Several causes have been implicated in SMA syndrome, including high insertion of the duodenum at the ligament of Treitz, low origin of the SMA, and compression of the duodenum due to peritoneal adhesions.^[3] Other factors that can decrease the aortomesenteric angle are shown.^[3,5,7] Rare causes of SMA syndrome include traumatic aneurysm of the SMA after a stab wound, as well as prior or family history of SMA syndrome.

This image shows high-grade partial obstruction at the distal second portion of the duodenum is due to SMA syndrome. The most common cause for this condition is a decrease in the angle between the SMA and the abdominal aorta. A normal aortomesenteric angle measures approximately 45° (range 38-60°) with the abdominal aorta. The transverse or third part of the duodenum crosses the aorta just inferior to the origin of the superior mesenteric artery. Any decrease in the aortomesenteric angle within 6-25° can cause compression of the third part of the duodenum as it passes between the superior mesenteric artery and aorta, resulting in SMA syndrome.^[3]

In this computed tomography (CT) image, the SMA traversed the loop of the duodenum in apparently normal anatomic position, but with reduction in the aortomesenteric angle (shown). In SMA syndrome, the aortomesenteric distance is also decreased, usually to within 2-8 mm (normal aortomesenteric distance is 10-20 mm).

Image from Radiopaedia.org, courtesy of Dr. Yuranga Weerakkody and Dr. Erik Ranschaert.

Patients with SMA syndrome often present with chronic upper abdominal symptoms (shown). Symptoms are often relieved when the patient is in the knee-to-chest, prone, or left lateral decubitus position. These positions are thought to decrease tension on the small bowel at the aortomesenteric angle. Symptoms may be exacerbated when the patient is in the supine position.^[8]

Radiologic studies are essential in the diagnosis of SMA syndrome. CT can best visualize retroperitoneal and mesenteric fat as well as measure the aortomesenteric distance. An upper GI series (shown) may reveal abrupt compression of the duodenal mucosal folds, dilated first and second portions of the duodenum, and a 4- to 6-hour delay in gastroduodenal transit. Endoscopy helps to rule out mechanical causes of duodenal obstruction. Both arteriography and ultrasound are useful for measuring the aortomesenteric distance and the angle of the SMA, which should be measured at the level of the third lumbar vertebral body.^[9,10,11]

Image from Radiopaedia.org, courtesy of Dr. Yuranga Weerakkody and Dr. Erik Ranschaert.

Several treatment options for have been proposed for SMA syndrome. Many patients with an acute first episode are successfully treated with medical intervention only.^[12,13] The general consensus for medical intervention is to initiate intravenous fluids, frequent small meals of liquids, and positioning the patient in the knee-chest position after eating. Metoclopramide therapy may also be helpful. Most chronic cases require surgery; indications are shown.

When surgical treatment is required, duodenojejunostomy is successful in the majority of cases. The procedure involves the creation of an anastomosis between the duodenum and jejunum bypassing the compression caused by the abdominal aorta and the SMA. Another approach involves lysis of the ligament of Treitz and mobilization of the duodenum, which eliminates the need for anastomosis and can be done laparoscopically.^[14] In our patient, no rapid weight loss was present. Scleroderma was the only condition that could be related to GI motility and enlarged duodenum. Upper GI tract series clearly showed dilatation of the second portion of the duodenum and abrupt compression of the duodenal folds.

Image from Wikipedia Commons, courtesy of Samantha S. Mina.

The aortomesenteric distance of 6.25 mm was measured on CT at the lower level of L2 (shown). Endoscopy showed no other mechanical reason to explain the patient's condition. The patient elected to have exploratory laparotomy. During the procedure, a dilated second portion of the duodenum was identified and a duodenojejunal bypass was done. Her postoperative course was satisfactory, and she was tolerating liquids within 72 hours without any evidence of epigastric fullness or vomiting. At her 1-year follow-up visit, the patient’s weight was 140 lb. She has remained free of symptoms.

Image from Radiopaedia.org, courtesy of Dr. Yuranga Weerakkody and Dr. Erik Ranschaert.