Esophageal Insufflation Computed Tomography in Normal Dogs

Abstract

Conventional CT for hollow organs such as esophagus is of limited value in evaluating esophageal lumen and luminal walls. The goals of this study were to determine the feasibility and describe the optimal technique for esophageal insufflation computed tomography (EICT) with CO2 insufflation alone and to develop a standardized methodology for EICT in dogs. Seven normal beagle dogs, each weighing 11.2–16.4 kg (mean, 14.27 kg) were used. EICT (unenhanced and contrast-enhanced) was performed using an electronic CO2 insufflator at pressures of 0, 5, and 10 mmHg in sternal recumbency during transient apnea by manual hyperventilation. After acquiring CT images at each pressure, measurements of esophageal cross-sectional luminal area (cm2) and wall thickness (cm) were performed at standardized locations (cervical, thoracic inlet, heart base, caudal intrathoracic, and abdominal segments) within the esophagus were evaluated. A value of P < 0.05 was considered as significant. Appropriate esophageal distention was observed at 5 and 10 mmHg, along with significant differences in the esophageal luminal cross-sectional areas at each pressure (P < 0.05). All dogs showed gas dilation of the stomach at a pressure of 10 mmHg and not 5 mmHg. The optimal initial insufflation pressure for EICT in this study was determined to be 5 mmHg. EICT resulted in consistent distension of the canine esophagus and is indicated for the evaluation of esophageal and extraesophageal disease in a single setting.