Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . The cardiomediastinal silhouette is unchanged and unremarkable since the prior examination . The aorta is unfolded . There is no focal consolidation . No pleural effusion or pneumothorax is identified . Air-filled colon is seen in the subdiaphragmatic region .
    OUTPUT:
    
No acute intrathoracic abnormality .