Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There has been interval development of a moderate right pneumothorax with slight contralateral shift of the mediastinal structures . Cardiac , mediastinal and hilar contours are otherwise normal . Lungs are clear . No pleural effusion is demonstrated . No acute osseous abnormalities detected .
    OUTPUT:
    
Moderate size right pneumothorax with mild leftward shift of mediastinal structures suggesting early tension .