Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright portable chest radiograph was provided . Upper lobe lucency is compatible with underlying emphysema . Vague opacities in the lower lungs may represent atelectasis versus scarring . These findings are less likely to reflect pneumonia . A tiny right pleural effusion is seen . The heart size is within normal limits . The mediastinal contour is unremarkable . Bony structures are intact .
    OUTPUT:
    
Emphysema with vague opacities in the lower lungs which most likely represent atelectasis / scarring , though pneumonia not entirely excluded in the correct clinical setting .