Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable semi-erect chest film dated ___ at 22 :07 is submitted .
    OUTPUT:
    
Lung volumes have diminished with patchy opacities at both bases suggestive of atelectasis in the setting of low lung volumes , although aspiration or pneumonia can not be excluded . There is likely a layering left effusion . No evidence of pulmonary edema . There is crowding of the vasculature given the low lung volumes . Overall cardiac and mediastinal contours are difficult to assess given the diminished lung volumes and patient rotation . No pneumothorax is appreciated .