Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable chest . The opacity seen in the left lower lobe on the prior radiograph is no longer present . There is chronic interstitial prominence as well as lucency of the upper lungs consistent with severe bullous emphysema . The hilar and cardiomediastinal contours are normal . There is no pneumothorax or pleural effusion .
    OUTPUT:
    
1 . Previous left lower lobe opacity has cleared . No evidence of new infectious process . 2 . Findings consistent with chronic lung disease including interstitial prominence and bullous emphysema .