Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size remains moderately enlarged . Mediastinal and hilar contours are unremarkable . The pulmonary vasculature is not engorged . Minimal patchy opacity is seen within the left lung base , possibly reflective of atelectasis . No pleural effusion or pneumothorax is seen . The osseous structures are diffusely demineralized .
    OUTPUT:
    
Patchy left basilar opacity most likely reflective of atelectasis . Infection however is not completely excluded .