Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable chest radiograph demonstrates unremarkable mediastinal , hilar and cardiac contours . Low lung volumes are noted bilaterally with vascular crowding in the lung bases . No focal opacifications evident . No pleural effusion or pneumothorax identified . On this non-dedicated rib series no displaced rib fractures are identified .
    OUTPUT:
    
No acute intrathoracic process .