Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is normal . The aorta is mildly tortuous . Mediastinal and hilar contours are otherwise unremarkable . Lung volumes are low which results in crowding of bronchovascular structures . No overt pulmonary edema is present . Patchy atelectasis is seen in the lung bases without focal consolidation . Minimal blunting of the right costophrenic angle suggests a trace right pleural effusion . No pneumothorax is present . There is no subdiaphragmatic free air . Mild degenerative changes are noted in the thoracic spine .
    OUTPUT:
    
No subdiaphragmatic free air . Mild bibasilar atelectasis and possible trace right pleural effusion .