Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is again a large pleural effusion occupying the mid - to - lower hemithorax with rightward mass effect although it is likely that the left lower lobe and parts of the left upper lobe , at least the lingula , are collapsed . The right lung remains clear . There is no pneumothorax . A prior healed right posterior lateral seventh rib fracture appears unchanged . Mild degenerative changes are similar along the lower thoracic spine .
    OUTPUT:
    
Similar large left - sided pleural effusion .