COMPARISON OF UPRIGHT INSPIRATORY AND EXPIRATORY CHEST RADIOGRAPHS FOR DETECTING PNEUMOTHORACES

OBJECTIVE, Expiratory films are regarded as being superior to inspirat ory films for pneumothorax detection, yet this has not been proved. In the current study, we compared inspiratory versus expiratory chest ra diographs for pneumothorax detection. MATERIALS AND METHODS. Eighty-fi ve paired inspiratory and expiratory radiographs with pneumothoraces a nd 93 pairs without pneumothoraces were randomly arranged and reviewed independently by three radiologists. A score of 1-5 was assigned for each hemithorax (5 = definite pneumothorax, 1 = definitely no pneumoth orax), Results were compared for inspiration and expiration using rece iver operating characteristic (ROC) analysis. RESULTS. The average are a under the ROC curves for all readers was .973 for inspiration and .9 72 for expiration (nonsignificant). McNemar's test and an alpha level of .05 also yielded no significant difference in sensitivity and speci ficity. Four of the 85 cases were scored as definite pneumothorax on i nspiration and as definitely not on expiration by all readers, and thr ee of the 85 cases were scored as definite pneumothorax on expiration and as definitely not on inspiration. CONCLUSION. Inspiratory and expi ratory upright films are equally sensitive for pneumothorax detection. Given the limitations of expiratory films, inspiratory films are reco mmended as the initial examination of choice for pneumothorax detectio n.