Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographdemonstrates mildly hypoinflated lungs with crowding of vasculature and left lower lobe linear platelike opacity only seen on frontal view . No pleural effusion or pneumothorax . Heart size , mediastinal contour , and hila are unremarkable . Limited assessment of the upper abdomen is within normal limits . A chronic lateral fifth rib fracture is noted .
    OUTPUT:
    
Left lower lobe atelectasis . No definite pneumonia .