Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Relatively low lung volumes are noted with secondary streaky left basilar opacity which is likely atelectasis . Elsewhere , lungs are clear . Cardiomediastinal silhouette is within normal limits . No acute osseous abnormalities . Compression deformity of the visualized upper lumbar vertebral body is unchanged .
    OUTPUT:
    
No definite acute cardiopulmonary process . Left basilar atelectasis .