Computed Tomographic Imaging of Dogs With Primary Laryngeal or Tracheal Airway Obstruction

Abstract

Seventeen dogs with clinical signs attributable to nonneoplastic obstruction of the larynx, trachea, or large bronchi underwent computed tomography (CT) imaging. In 16 of the 17 dogs, CT was performed without general anesthesia using a positioning device. Fifteen of these 16 dogs were imaged without sedation or general anesthesia. Three-dimensional (3D) internal rendering was performed on each image set based on lesion localization determined by routine image planes. Visual laryngeal examination, endoscopy, video fluoroscopy, and necropsy were used for achieving the cause of the upper airway obstruction. The CT and 3D internal rendering accurately indicated the presence and cause of upper airway obstruction in all dogs. CT findings indicative of laryngeal paralysis included failure to abduct the arytenoid cartilages, narrowed rima glottis, and air-filled laryngeal ventricles. Laryngeal collapse findings depended on the grade of collapse and included everted laryngeal saccules, collapse of the cuneiform processes and corniculate processes, and narrowed rima glottis. Trachea abnormalities included hypoplasia, stenosis, or collapse syndrome. The CT findings in tracheal hypoplasia consisted of a severely narrowed lumen throughout the entire length. Tracheal stenosis was represented by a circumferential decrease in tracheal lumen size limited to one region. Tracheal collapse syndrome was diagnosed by severe asymmetric narrowing. Lobar bronchi collapse appeared in CT images as a narrowed asymmetric lumen diameter. CT imaging of unanesthetized dogs with upper airway obstruction compares favorably with traditional definitive diagnostic methods.

Glottic and skull indices in canine brachycephalic airway obstructive syndrome

“…Recently, cephalometric measurements and obstruction in brachycephalic dogs have also been evaluated by Computed Tomographic Imaging [6,38,39]. …”

Qualitative and quantitative interpretation of computed tomography of the lungs in healthy neonatal foals

“…A specially designed restraint device has greatly facilitated CT imaging in awake or minimally sedated cats and small dogs. 6,27,28 For safety and practical reasons, larger animals, particularly neonatal foals, cannot undergo imaging when awake; however, the use of short-term IV sedation may provide a safe alternative to anesthesia in this population of animals.…”

Effects of thiopentone, propofol and alfaxalone on laryngeal motion during oral laryngoscopy in healthy dogs

“…This may be achieved via direct visualisation of the larynx with a simple laryngoscope, transoral video-endoscopic laryngoscopy, transnasal video-endoscopic laryngoscopy, echolaryngography or computed tomography (CT) (MacPhail 2014, Radlinsky et al 2009, Stadler et al 2011. Transnasal video-endoscopic laryngoscopy, echolaryngography and CT avoid the need for heavy sedation/general anaesthesia, but these methods have not been shown to be superior to transoral laryngoscopy.…”