In 1956, Rockey and his associates developed and reported tracheal fenestration operation for the treatment of purulent infections of the lungs through animal experiments. In 1970, Hiroto recognized wide applicability of the tracheal fenestration operation, and modified Rockey's original complicated method into a simpler one. The authors applied the Hiroto's modification of tracheal fenestration operation to the patient, and found many advantages of this method in comparison with conventional tracheostomy. Furthermore, another modified method was applied with satisfactory result to the cases who had decanulation difficulty due to overgrowth of granulation tissue at the tracheostomy site.