Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiograph demonstrates clear lungs without effusion or pneumothorax . A paired tubular structure superimposed upon the left mid-lung is noted of uncertain significance . The cardiac silhouette is normal , the mediastinal contours are unremarkable . The pulmonary vasculature is normal in appearance .
    OUTPUT:
    
A paired tubular structure superimposed upon the left mid-lung is noted of uncertain significance . While this may be a normal vascular variant , further evaluation with contrast enhanced CT chest is recommended . Findings discussed with Dr . ___ by phone at 5 : 15 pm .