Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Rotated positioning . Compared with ___ , there has been progressive opacification of the left lung , now with only a small residual area of aerated lung seen at the left lung apex . There is probable slight shift of mediastinum to the left , similar to prior . Appearance is not fully characterized , but suggests the presence of a large effusion with underlying collapse and / or consolidation . The left hemidiaphragm could be elevated . Right lung is grossly clear , without focal infiltrate or effusion . Atelectasis noted in the right cardiophrenic region . There is slight upper zone redistribution , but no overt CHF . As before , the patient 's left elbow is flexed , with the hand overlying the lateral edge of the upper left chest .
    OUTPUT:
    
Progressive opacification of the left lung , with leftward shift of the mediastinum again seen and with possible elevation left hemidiaphragm , all suggesting considerable left side volume loss . Presence of a left - sided effusion is suspected . Interval improvement in degree of vascular plethora . Aside from upper zone redistribution , doubt CHF . Right lung grossly clear . Minimal atelectasis at the right cardiophrenic region is noted .