Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single portable view of the chest . Lower lung volumes seen on the current exam . Patchy region of opacity identified at the left lung base . Elsewhere , the lungs are clear . The cardiomediastinal silhouette is within normal limits . Tortuosity of the descending thoracic aorta is noted . Partially visualized apparently chronic deformity of the proximal right humerus is also seen .
    OUTPUT:
    
Left basilar opacity could be due to atelectasis , although infection can not be entirely excluded and please correlate clinically . Otherwise , no acute cardiopulmonary process . If desired , PA and lateral could be obtained to further characterize .