Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest . The lungs are clear . There is a small to moderate left - sided pneumothorax . There is no evidence of mediastinal shift . Cardiomediastinal silhouette is within normal limits . Osseous and soft tissue structures are unremarkable .
    OUTPUT:
    
Small to moderate left pneumothorax . Findings were paged to emergency department resident Dr . ___ at 19 :53 at time of discovery .