Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are relatively low lung volumes . No focal consolidation is seen . Large hiatal hernia is seen . There is slight blunting of the posterior costophrenic angles may be due to atelectasis , however , trace pleural effusion not excluded . Cardiac and mediastinal silhouettes are stable . No pneumothorax is seen . There is no overt pulmonary edema . Degenerative changes of the partially imaged glenohumeral joints again noted .
    OUTPUT:
    
Large hiatal hernia . Slight blunting of the posterior costophrenic angles on the lateral view may be due to atelectasis , but trace pleural effusion not excluded .