Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart is normal size and mediastinal contours are unremarkable . Lucent appearance of the upper lungs , right more than left , and hyperinflation is suggestive of underlying emphysema . Diffuse bilateral interstitial opacities with prominence of the hilar structures may represent mild pulmonary interstitial edema , however , an atypical infection may have a similar appearance . Opacification of the left costophrenic angle may represent pleural thickening or a small pleural effusion .
    OUTPUT:
    
1 . Underlying emphysema and chronic interstitial changes . 2 . Bilateral interstitial opacities may be due to mild pulmonary interstitial edema or atypical pneumonia . Follow - up chest radiograph after diuresis would be helpful .