RADIOGRAPHIC EVALUATION OF INDUCED PNEUMOTHORAX IN THE DOG

Serial radiographic examinations were used to assess the incidence of bilateral and unilateral pneumothorax and its resolution following the introduction of air into a pleural space in each of 24 adult mix-bree d dogs. Twenty-two (92%) dogs developed bilateral pneumothorax and two dogs (8%) developed unilateral pneumothorax. Volumes of air equal to 5 ml/kg, 15 ml/kg, and 45 ml/kg of body weight had resolved in all dog s developing bilateral pneumothorax by 7, 10, and 14 days, respectivel y. The vertical beam left lateral recumbent and the expiratory horizon tal beam ventrodorsal views were the most effective radiographic views for the detection of pneumothorax. Separation of the visceral and par ietal pleural surfaces on the horizontal beam ventrodorsal view was a better indication of small amounts of air in the pleural spaces than s eparation of the heart from the sternum on the vertical beam lateral v iew. The right lateral recumbent view, regardless of beam orientation, was most sensitive for the detection of differences in the amount of air in the pleural spaces.