Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and 2 lateral views of the chest . On the frontal exam , the lungs are clear . On 1 of the 2 lateral exams there is increased opacity projecting near the posterior costophrenic sulci which clears on the ___ lateral view and is likely due to atelectasis . There is no pleural effusion . The cardiomediastinal silhouette is within normal limits . No acute osseous abnormalities detected .
    OUTPUT:
    
No definite acute cardiopulmonary process .