Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a chronic diffuse interstitial abnormality that is not significantly changed compared to the prior radiograph from ___ from ___ . Focal heterogeneous opacity in the left retrocardiac region has been seen on prior radiographs , possibly scarring / atelectasis , although infection is certainly possible . Mild enlargement of the cardiac silhouette is not significantly changed . The mediastinal contours are normal . There are no definite pleural effusions . No pneumothorax is seen .
    OUTPUT:
    
1 . Heterogeneous left retrocardiac opacities are not significantly changed compared to prior radiographs dating back through ___ , possibly reflecting atelectasis or scarring , although new infection in this region is certainly possible . If there is persistent concern for infection , recommend dedicated PA and lateral views for further evaluation . 2 . Chronic diffuse interstitial abnormality , not significantly changed .