Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Right mainstem bronchus intubation , recommend retraction of endotracheal tube . Low lung volumes accounting for apparent bronchovascular crowding . No focal consolidations seen . Streaky retrocardiac opacity likely represents atelectasis . There is no pleural effusion or pneumothorax . Median sternotomy wires are present .
    OUTPUT:
    
Right mainstem bronchus intubation , recommend retraction of endotracheal tube for more optimal positioning .