Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Tracheostomy tube remains in unchanged position . Cardiac , mediastinal and hilar contours appear similar . Reduced lung volumes are re- demonstrated . Diffuse interstitial opacities are compatible with a chronic interstitial lung disease , not substantially changed from prior . Interval development of more focal patchy opacities in the lung bases compared to the recent radiograph may reflect superimposed infection or aspiration . There may be superimposed mild pulmonary vascular congestion . No pleural effusion or pneumothorax is seen . Mildly distended air-filled loops of bowel are seen within the imaged upper abdomen .
    OUTPUT:
    
Interval development of more focal bibasilar airspace opacities which may reflect infection or aspiration superimposed on a background of chronic interstitial lung disease . There may be mild pulmonary vascular congestion .