Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . There is elevation of the left hemidiaphragm with colonic interposition . Aside from the left lower lobe subsegmental atelectasis , the lungs are grossly clear . There is no pneumothorax . The heart and mediastinum are grossly unremarkable . A chronic left distal clavicular fracture and AC joint dislocation is incidentally noted . Irregularly shaped opacities at the left AC joint may be due to heterotopic ossification .
    OUTPUT:
    
Assessment limited by low lung volumes . Left lower lobe subsegmental atelectasis with no evidence of pneumonia .