Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . Relatively low lung volumes are again noted . There is a left basilar opacity which silhouettes portion of the hemidiaphragm . Superiorly , the left lung and the right lung are clear . There is also suggestion of trace right - sided effusion given blunting of the right posterior costophrenic angle . The cardiomediastinal silhouette is unchanged and likely accentuated by low lung volumes . No acute osseous abnormality is identified .
    OUTPUT:
    
Left basilar opacity potentially due to a combination of effusion , atelectasis with possible superimposed infection . Probable trace right pleural effusion .