Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes remain low . The cardiac and mediastinal contours are unchanged , with mild cardiomegaly re - demonstrated . Diffuse interstitial opacities are again noted , compatible with known chronic interstitial lung disease . Crowding of the bronchovascular structures with mild cephalization and indistinctness of the pulmonary vascular markings suggest mild superimposed pulmonary edema . No pleural effusion or pneumothorax is seen . No acute osseous abnormalities are demonstrated .
    OUTPUT:
    
Little interval change compared to the prior exam with mild pulmonary edema superimposed on a background of chronic interstitial lung disease .