Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable semi-erect chest radiograph ___ at 11 :08 is submitted .
    OUTPUT:
    
Tracheostomy tube remains in satisfactory position . Lungs are diminished in volume but the parenchymal distortion is once again seen consistent with known underlying emphysema . There has been interval appearance of patchy opacity in the retrocardiac area which more likely reflects atelectasis , although aspiration and developing pneumonia should also be considered . No pneumothorax . Cardiac and mediastinal contours are stable with the heart being stably enlarged .