Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest were obtained . There are linear densities in the lower lungs which are most compatible with scarring and appear essentially stable from the prior exam . There is no definite sign of pneumonia or CHF . No pleural effusion or pneumothorax is seen . Cardiomediastinal silhouette is stable with top normal heart size with atherosclerotic calcifications along the unfolded thoracic aorta . The imaged osseous structures demonstrate diffuse osseous demineralization and old rib deformities in the left rib cage .
    OUTPUT:
    
Areas of scarring in the lower lungs . Please note , given this appearance , a subtle nodule may be obscured . If there are elevated risk factors for lung cancer , non-emergent CT of the chest may be obtained . No definite signs of acute intrathoracic process .