RABBIT PNEUMOTHORAX - FEASIBILITY OF AN ANIMAL-MODEL TO SIMULATE NEONATAL PNEUMOTHORAX

RATIONALE AND OBJECTIVES. The feasibility of developing an animal model to simulate radiographic features of neonatal pneumothorax was investigated, and supine computed radiography (CR) and film-screen radiography (FS) images were compared. METHODS. 5-Fr pigtail catheters were inserted into the right pleural space of three New Zealand white rabbits. Two CR and two FS supine images were obtained using identical technique. After serial 4-mL injections of air, one CR and one FS supine image were obtained. The images were masked and randomized, and four radiologists reviewed the images for typical signs of pneumothorax. Chest computed tomography (CT) was performed before the injection of any air and after completion of the study. RESULTS. At zero-mL air volume, radiologists did not perceive a pneumothorax. As the air volume increased, the number of signs of a pneumothorax increased; there was no significant difference between CR and FS in the number of signs of pneumothorax detected at any volume. Chest CT confirmed that there was no unexplained air leak. The volume of air injected correlated with the calculated volume from the CT. CONCLUSIONS. This induced, volume-controlled, animal model simulated the supine radiographic features of neonatal pneumothorax.