Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and two lateral chest radiographs were obtained . Lung volumes are low . The lungs are clear without nodule , consolidation , effusion , or pneumothorax . Mild cardiomegaly is unchanged . No displaced rib fracture is identified .
    OUTPUT:
    
Low lung volumes . No acute cardiopulmonary process .