Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear stable . There is no pleural effusion or pneumothorax . There is again an opacity in the right middle lobe and , more generally , an interstitial abnormality in the lower lungs . However , this appearance is very similar to the prior radiographs . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Similar interstitial abnormality and focal right middle lobe opacities ; possibilities include an acquired chronic interstitial abnormality with right middle lobe atelectasis , but recurrence of acute infectious process with the same pattern as before is not excluded .