Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size is within normal limits . No typical configurational abnormality is identified . Unremarkable appearance of thoracic aorta contour . The pulmonary vasculature is not congested . There exists a right - sided paramediastinal density within the concave outer contour most likely representing an atelectasis of the apical portion of the right upper lobe . There is no evidence of pneumothorax . No other acute pulmonary abnormalities are seen on this portable chest examination . As our records do not include a preceding chest examination , the scout film of a PET - CT examination transferred into our records and dated ___ was inspected . The atelectasis resembling right superior density existed already at that time .
    OUTPUT:
    
No evidence of pneumothorax .