Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since the 5 :31 a .m . examination , there has been improved aeration of the left lower lobe , likely reflecting post - bronchoscopic change . However an underlying flat fluid level raises the suspicion for possible superimposed pneumo / hydro - thorax . There remains severe left lower lobe atelectasis . The cardiac and mediastinal contours are unchanged . The endotracheal tube , orogastric tube , and left subclavian lines are unchanged in position . There is no pneumothorax . A small left pleural effusion is again seen . There is central pulmonary vascular congestion with mild interstitial edema .
    OUTPUT:
    
Improved aeration of the left lower lobe , post bronch . Underlying flat fluid level raises the suspicion for possible superimposed pneumo / hydro - thorax . The findings were communicated by Dr . ___ to ___ of Cardiac Surgery via telephone at 12 : 16 , ___ .