Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Evaluation is limited by head positioning , which obscures the lung apices . Within this limitation , there is little change in left upper lung opacity . Low lung volumes and reticular opacities at the lung bases are unchanged and consistent with stated history of IPF . The cardiomediastinal silhouette is stable . There is no pneumothorax .
    OUTPUT:
    
No change in left upper lung opacity or findings related to IPF .