Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Cardiac silhouette size remains mild to moderately enlarged . Mediastinal and hilar contours are unchanged , with mild calcification of the aortic knob . The pulmonary vasculature is normal . Apart from minimal atelectasis within the left lung base , the lungs are clear without focal consolidation , pleural effusion or pneumothorax . Right VP shunt catheter is partially imaged . Fusion hardware within the thoracolumbar junction is also partially imaged .
    OUTPUT:
    
Minimal left basilar atelectasis . Otherwise , no acute cardiopulmonary abnormality .