Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . There are bilateral lower lobe opacities at least in part explained by atelectasis . A left perihilar opacity has been present since at least mid-___ . The hilar and cardiomediastinal contours are normal . There is no pneumothorax . There is likely a small right - sided pleural effusion . Pulmonary vascularity is normal .
    OUTPUT:
    
Right lower lobe and middle lobe opacities likely secondary to atelectasis with a small right pleural effusion . Left perihilar opacity is subacute and has been present post - transplant since at least mid-___ .