Volvulus

Gastric volvulus is a rotational torsion of the stomach around either its longitudinal or transverse axis. Typically > 180 degrees of twisting is required to produce complete luminal obstruction. In order for volvulus to occur there must be relaxation of the suspensory ligaments or mesenteries. One third of cases have associated diaphragmatic abnormalities. Additional factors predisposing to volvulus include acute gastric dilatation, overfilling, prolonged vomiting, and sudden increases in intraabdominal pressure.

Gastric volvulus may occur at any age and can be either an acute or chronic condition. Acute volvulus typically presents with abrupt onset of epigastric pain and intractable retching. It is a surgical emergency as vascular occlusion with necrosis may ensue. There are two types of volvulus:

1. Organoaxial: Rotation around the gastric long axis extending from the cardia to pylorus. This form of volvulus is most common and is rarely associated with gastric ischemia.

2. Mesenteroaxial: Rotation around the gastric short axis extending from the greater to lesser curvature along the mesenteric attachment of the omemtum (perpendicular to the long axis). This form of volvulus is generally considered to be more serious due to an increased incidence of vascular compression and resulting tissue ischemia.

Radiographic Findings:

• Massively distended stomach with potentially two air fluid levels demonstrated on upright abdominal film

• Incomplete or absent contrast filling the stomach

• "Beak" sign at transition point

• Organoaxial: The greater curvature will be situated superiorly with the lesser curvature lying inferiorly. The GE junction and pylorus will be in their normal locations.

• Mesenteroaxial: The locations of the GE junction and pylorus are reversed relative to the body midline; the GE junction is located to the right, the pylorus to the left.