Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lungs are low in volume but clear aside from minimal bibasilar atelectasis . There is no pleural effusion or pneumothorax . The heart is likely top normal in size though not well assessed due to low lung volumes . Hilar and mediastinal contours are unremarkable .
    OUTPUT:
    
No acute intrathoracic process .