Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are low lung volumes . Enlargement of the cardiomediastinal silhouette may be accentuated by the low lung volumes and AP portable technique , however , if there is clinical concern for mediastinal injury , chest CTA is more sensitive . No definite focal consolidation is seen . There is no evidence of pneumothorax . Is difficult to exclude trace pleural effusions .
    OUTPUT:
    
Enlargement of the cardiomediastinal silhouette may be accentuated by the low lung volumes and AP portable technique , however , if there is clinical concern for mediastinal injury , chest CTA is more sensitive and should be considered . Difficult to exclude trace pleural effusions .