Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is at the upper limits of normal size . The mediastinal and hilar contours appear within normal limits . Incidental note is again made of an azygos fissure , consistent with a normal variant . There is a patchy left basilar opacity , predominantly in the left lower lobe , which is nonspecific but probably compatible with atelectasis . There is no pleural effusion or pneumothorax . Bony structures are unremarkable . A deformity involving the course of the right lateral seventh rib appears unchanged and may be due to remote prior trauma .
    OUTPUT:
    
Patchy left basilar opacity , new but probably compatible with atelectasis . Clinical correlation is suggested , however .