Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Interstitial markings are increased in the pulmonary vasculature is indistinct . There is no pneumothorax . The cardiac silhouette is prominent but may be exaggerated by AP technique . Mediastinal structures are otherwise unremarkable and appear stable . There are degenerative changes in the spine . Bilateral stimulator generator packs and leads overlie the upper chest and neck as before .
    OUTPUT:
    
Increased interstitial markings , possibly representing edema .