Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: An opacity at the right heart border may represent crowding of mediastinal structures in the setting of low lung volumes , however pneumonia can not be excluded . There is no pneumothorax , fracture or dislocation . Limited assessment of the abdomen is unremarkable .
    OUTPUT:
    
Equivocal opacity at the right heart border may represent crowding of mediastinal structures due to low lung volumes , however pneumonia can not be excluded .