ERS3068. A New Twist on Gastric Volvulus: An Interdisciplinary Approach Redefining Organo-Axial Rotation versus Volvulus
Authors * Denotes Presenting Author
  1. Clare Arroyo *; The University of New Mexico Hospital
  2. Ujwal Chadha; UT Health Houston
  3. Jonathan Revels; NYU Grossman School of Medicine
  4. Martha Terrazas; Cleveland Clinic
  5. Rachel Runde; University of Kansas Health System
  6. Steven Eberhardt; The University of New Mexico Hospital
  7. William Thompson; The University of New Mexico Hospital
Volvulus can occur at any point along the alimentary and grave sequelae can result if untreated. Imaging has been a mainstay in diagnosing acute gastric volvulus; however, due to its inherent rarity, clinical non-specificity, overlap with comorbidities, confusion in nomenclature and inappropriate synonymous application of terminology between organo-axial volvulus (OAV) and organo-axial rotation (OAR), these disease processes continue to prove a diagnostic challenge to radiologists. Previous literature has only sought to identify various computed tomography findings that correlate with diagnosis of volvulus; but we investigated how radiologists can apply these findings to delineate OAV from OAR. Additionally, we seek to depart from the literary consensus that volvulus requires a 180° of torsion to be diagnostic and instead postulate that any degree of gastric torsion in conjunction with the presence of least one secondary radiographic sign suggestive of gastric obstruction or vascular compromise is diagnostic of volvulized stomach. This interdisciplinary definition ensures that there is nomenclature and clinical agreement.

Materials and Methods:
Clinical records were queried for patients with OAR and OAV in radiologic dictations from 1/1/13-12/31/18. 45 patients with CT imaging were selected. Five fellowship trained, four body and one dual body and thoracic, radiologists with post-fellowship, attending level experience ranging from two to forty-three years were blinded and asked to independently analyze the CTs for the presence, absence, or indetermination of sixteen previously established secondary signs linked with the diagnosis of OAV. No preliminary training sessions were provided to prevent priming and subsequent skew of true inter-observer reliability when establishing a diagnosis of OAV or OAR. Statistical analysis evaluated inter-observer agreement and the sensitivity of CT findings differentiating OAR from OAV. Analysis was performed to determine if any clinical indicators are diagnostic of OAV vs OAR.

True OAV occurred in 4 of 45 patients (8.9%), with 41 of 45 exhibiting OAR (91.1%). Among the radiologists, agreement of secondary CT signs was greater than 90% on all scales except for classification of OAV or OAR which had 67% agreement. We were unable to prove with statistical significance that any one clinical symptom is predictive of OAV due to the small number of true OAV cases.

Historically, OAV has been defined as more than 180° of torsion along the longitudinal axis; however, a quantitative degree of rotation cannot be determined by imaging and is not definitively supported in the literature. There is a profound gap in the current knowledge that can lead to dramatic consequence as these two processes imply stark differences in severity of illness and clinical management. We seek to reinforce that the radiologist and surgeon must utilize this new definition of OAV/OAR relying on secondary signs, laid out and validated through our study, to diagnose a volvulized stomach.