Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are somewhat low but unchanged from prior . The cardiomediastinal silhouette , hilar contours and pleural surfaces are normal . There is no cardiomegaly . There is no frank pulmonary edema . A VP shunt is in stable position compared to prior study of ___ . There is no large pleural effusion or pneumothorax .
    OUTPUT:
    
No acute cardiopulmonary abnormality .