Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Within this limitation , the lungs are clear . The heart size is mildly enlarged . There is no large pleural effusion or pneumothorax . Mediastinal silhouette and hilar contours are normal allowing for low lung volumes . Pulmonary vasculature is normal . There is no osseous abnormality .
    OUTPUT:
    
No acute intrathoracic abnormality .