Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are grossly clear . No confluent opacities identified . There is no pulmonary edema or pleural effusions . No pneumothorax is evident . Moderately severe enlargement of the pulmonary arteries is similar to prior and consistent with patient 's underlying history of pulmonary arterial hypertension , better assessed on prior chest CT from ___ . Additional rounded hyperdensities overlying the mediastinum likely correspond with known calcified mediastinal lymph nodes . vague opacity right midzone laterally is consistent with scarring seen on ___ CT scan . Known small calcificed granulomas not visualized .
    OUTPUT:
    
No acute pulmonary process .