“…The earlier surgical procedures for the prevention of tracheobronchial collapse implied support of the pars membranacea (Hertzog, 1958;Rainer, Newby & Kelble, 1968;Rainer, Newby & Dirks, 1971;Hertzog, Keller & Allgower, 1972). However, during asthmatic attack both the cartilaginous and membranous parts collapse (Rayl, 1965;Standertskjold-Nordenstam, Halttunen & Meurala, 1981).…”