Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is a very large pleural effusion occupying much of the right hemithorax with mild leftward shift of mediastinal structures and inferred atelectasis of much of the right lung . A portion of the right upper lobe remains aerated , however . Patchy left basilar opacity suggests minor atelectasis . There is no definite pleural effusion on the left .
    OUTPUT:
    
Large right - sided pleural effusion . Evaluation with chest CT , preferably with intravenous contrast , may be helpful to assess further .