Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Rotated positioning . Left - sided pacemaker is present , lead tips unchanged . This obscures small portion of the left lateral chest . Compared with the prior film , catheter at the left lung base is no longer visualized . Otherwise , the appearance is similar , except for slight increase in the amount of increased retrocardiac density -- ___ could reflect some increased pleural fluid and / or collapse and / or consolidation . The ovoid lucency seen medially , as before , could represent a small amount of loculated pneumothorax . No pneumothorax is seen at the left lung apex . The appearance of the right lung is unchanged , with a small right base pleural effusion , but otherwise no infiltrate or consolidation . No right - sided pneumothorax . No CHF .
    OUTPUT:
    
Left base catheter no longer seen . Slight interval increase in degree of retrocardiac opacity / left base fluid . As before , loculated pneumothorax at the right base medially can not be excluded , similar to prior . Alternatively , this could represent aerated lung , in the context of left base opacity . Small amount of right base pleural fluid is unchanged .