Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single supine view of the chest . As on prior , low lung volumes are seen . There is no evidence of confluent consolidation or large effusion . The cardiomediastinal silhouette is stable . Degenerative changes noted at the shoulders bilaterally and an old left lateral inferior rib fracture .
    OUTPUT:
    
Low inspiratory effort . No evidence of acute cardiopulmonary process .