SAEVA Proceedings 2018 4. Proceedings | Page 53

SAEVA Congress 2018 Proceedings | 12-15 February 2018 | ATKV Goudini Spa Rib fracture Lung contusion The cells and cellular debris in pyothorax are more echogenic, heavier, and in the most ventral location while the less cellular fluid or gas cap is detected dorsally. Free gas within the fluid (polymicrobullous fluid) is imaged as small, very bright hyperechoic echoes within pleural fluid with more free gas echoes imaged dorsally in the pleural fluid. The echoes from the microbubbles are usually pinpoint and linear. The mixing of air or gas microbubbles and pleural fluid creating polymicrobullous fluid. The microbubble echoes move rapidly and spontaneously in various directions depending upon respiratory, cardiac, and the horse's movements. The free gas echoes often adhere to the fibrinous pleural surfaces and may be detected here initially without being mixed into the pleural fluid . Free gas echoes may also be compartmentalized in only one portion of the thorax when initially imaged, but usually spread rapidly to all portions of the thorax. Free gas echoes are usually caused by an anaerobic infection within the pleural cavity. Free gas echoes were detected in the pleural or abscess fluid of 74% of horses with confirmed anaerobic pneumonia. 48