E1357. Untwisting the Confusion Between Organo-Axial Volvulus and Rotation: What the Radiologist Needs to Know
  1. Ujwal Chandha; University of New Mexico
  2. Clare Arroyo; University of New Mexico
  3. Tabitha Kirkendall; University of New Mexico
  4. Herbert Davis; University of New Mexico
  5. Steven Eberhardt; University of New Mexico
  6. William Thompson; University of New Mexico
Organo-axial volvulus (OAV) is a rare diagnosis defined as gastric rotation >180° along its long axis with subsequent obstruction and ischemia. OAV classically present with Borchardt's Triad of epigastric pain, non-productive retching, and inability to pass an NGT. Confusion emerges in terminology as some patients have a partial <180° gastric rotation with no symptoms of obstruction, termed organo-axial rotation (OAR). OAR and OAV are often used interchangeably by radiologists and clinicians, but these terms imply different severity of illness and clinical management and must be differentiated. OAR is not uncommon, often incidentally found on CT or barium studies, and comparatively more common than OAV. Surgery for OAR is usually to correct comorbid hiatal hernia. As it is infeasible to measure the exact angle of gastric rotation radiologically, OAV is diagnosed on CT by presence of secondary signs of gastric outlet obstruction, peri-gastric fluid, and gastric ischemia. However, even these secondary signs may be unreliable predictors of acute symptoms and need for urgent surgical intervention. We assert that OAR is a chronic, acutely asymptomatic finding, and should be diagnosed as a distinct entity. These patients commonly have symptoms of Gastroesophageal Reflux Disease (GERD) and are treated accordingly. OAV is not a purely radiologic diagnosis and must be supported by clinical findings. These patients undergo emergent endoscopic gastric decompression and/or surgery.

Educational Goals / Teaching Points
After reviewing this poster the reviewer will: 1. Know the appropriate clinical, imaging and treatment for OVR and OAV. 2. Know the specific imaging findings of OAR and OAV. 3. Know the role of CT and the UGI in the evaluation of patients with OAR and OAV. 4. Know the appropriate terminology for the two entities.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
OAR versus OAV. Rotation of Stomach. Gastric Outlet Obstruction and Gastric Ischemia. Imaging findings of OAR and OAV.

1. OAR is not uncommon. 2. OAV is rare. 3. The clinical presentation, imaging findings and treatment are very different for OAR versus OAV. 4. Most patients with OAR have symptoms of GERD and are treated clinically or have anti-reflex surgery. 5. OAV classically can present with Borchardt's Triad of epigastric pain, non-productive retching, and inability to pass an NGT. 6. The CT findings of QAV are gastric outlet obstruction and gastric ischemia (thickened gastric wall, decreased contrast enhancement of the gastric wall and peri-gastric fluid). 7. OAV patients are treated with emergent endoscopic gastric decompression and/or surgery. 8. Clinicians and radiologists must correctly characterize OAR versus OAV.