Inclusion Criteria:  Persistent clinical signs of inspiratory stridor, combined with high pitched cry, hoarse voice, persistent cough or recurrent inspiratory tract infections Bronchoscopic conferment of tracheal stenosis from the subglottic area to the area above carina Maintenance of clinical symptoms despite intensive and long drug therapy with inhalational steroids, adrenalin or salbutamol Urgent need for expansion of trachea, because of risk of full obstruction of trachea  Exclusion Criteria:  children with haemodynamic instability prior or during the procedure children with active respiratory tract infection children with low hemoglobin levels - anemia children with physical status, according to the American Society of Anesthesiologists, III and IV parents who refuse the participation of their children in the study and to sign the informed consent