Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes . The bilateral hemidiaphragms , cardiac borders , and mediastinal silhouettes are normal without pleural effusion or pneumothorax . Right upper lobe opacification is noted without definite correlate on lateral view .
    OUTPUT:
    
Right upper lobe opacification may be due to overlapping osseous structures or pneumonia in the right clinical setting . Apical lordotic radiographs are recommended to differentiate osseous from pulmonary structures .