Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . Linear left base and right perihilar opacities may be due to atelectasis given lower lung volumes . Elsewhere , the lungs are clear . There is no effusion or pulmonary vascular congestion . Surgical clips project over the right lung apex as on prior . The cardiomediastinal silhouette is within normal limits . Posterior fixation hardware is seen at the lower thoracic , upper lumbar region as on prior . No acute osseous abnormality is detected .
    OUTPUT:
    
No definite acute cardiopulmonary process .