Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal and hilar contours appear unchanged . There is patchy left basilar opacification , but decreased , and probably compatible with atelectasis . There is no definite pleural effusion , although an effusion would be difficult to exclude on the left side . There is no pneumothorax . Degenerative changes and spinal curvature appear similar along the visualized thoracolumbar spine .
    OUTPUT:
    
Patchy left basilar opacification , but decreased , and accordingly likely due to resolving atelectasis or potentially improving infection in the appropriate setting .