Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size remains mildly enlarged . Mediastinal contour is similar . Perihilar haziness and vascular indistinctness is compatible with mild pulmonary edema , somewhat improved from the previous study . Emphysematous changes are again seen within the upper lobes . Focal opacity in the left perihilar region could reflect an area of superimposed infection . Increased interstitial opacities in the lung bases are compatible with a mild chronic interstitial lung disease , as seen on the previous CTs . No pleural effusion or pneumothorax is seen . The osseous structures are diffusely demineralized with multiple compression deformities noted at the thoracolumbar junction , unchanged . Cervical spinal fusion hardware is not completely imaged . Multiple clips are noted in the upper abdomen .
    OUTPUT:
    
Mild pulmonary edema superimposed on a background of chronic interstitial lung disease . More focal opacity in the left perihilar region could reflect an area of infection .