Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal upright and lateral chest radiographs demonstrate well - expanded lungs . Heart is top normal in size and cardiomediastinal contour is unchanged compared to the prior examination . Linear bibasilar opacities including linear retrocardiac opacities on the lateral projection were also present on the prior examination and likely reflect atelectasis / scarring . There is no pleural effusion . There is no pneumothorax . Degenerative changes are noted in the spine .
    OUTPUT:
    
No acute cardiopulmonary process .