Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Heart size is normal . The aorta remains mildly tortuous . Mediastinal and hilar contours are unremarkable . Streaky atelectasis is demonstrated in both lung bases , more pronounced on the left . No focal consolidation , pleural effusion , or pneumothorax is present . Pulmonary vasculature is not engorged . Known soft tissue lesion involving the left seventh anterolateral rib likely accounts for the somewhat triangular opacity projecting over the left costophrenic angle , better assessed on the previous CT .
    OUTPUT:
    
Bibasilar atelectasis and low lung volumes .