Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left costophrenic angle and lateral left lung base is excluded from the film . A tracheostomy tube is again noted . There is upper zone redistribution , with mild vascular plethora , consistent with early CHF , slightly more pronounced . There are non-specific bibasilar opacities , slightly improved at the right lung base . As before , the differential includes CHF , aspiration , or pneumonic infiltrates .
    OUTPUT:
    
As above . .