Today’s case is a 12-year-old male Labrador Retriever with 1.5-year history of cough and stridor. What do you think? Please comment!
On lateral radiographs of the neck, there is increased opacity in the region of the larynx. There is air collected in the laryngeal saccules. The soft palate appears thickened, and there is air in the proximal esophagus. The patient is obese.
Within the thorax, there is poor inflation with the diaphragm remaining in a relatively vertical position and contacting the entire caudal border of the heart. There is increased opacity throughout the lungs, with a bronchointerstitial pattern. The cranial mediastinum is uniformly widened on the d/v projection with no evidence of a mass on the lateral projection. The heart and vessels appear normal.
The air in the laryngeal saccules can be associated with laryngeal paralysis. Thickening of the larynx and soft palate may be due to edema or fibrosis from chronic upper airway obstruction. The pulmonary changes are likely mainly due to hypoinflation from upper airway obstruction; however, additional airway or parenchymal disease cannot be ruled out. Thoracic radiographs under positive pressure ventilation or post laryngeal surgery may be considered to rule out other lung changes.
Bilateral laryngeal paralysis was confirmed by visualization under anesthesia, and a unilateral arytenoid lateralization surgery was performed.
Although laryngeal thickening and air in the saccules are non specific, they are often associated with laryngeal paralysis. This, along with the history, supported the clinical suspicion of laryngeal paralysis. The changes in the appearance of the lung due to upper airway obstruction and obesity can be profound; however, they often improve once the ability to fully inflate is restored.