He recommended the operation only as a last resort in cases of airway obstruction by foreign bodies or secretions.[7] Fabricius' description of the tracheotomy procedure is similar to that used today. Julius Casserius (1561–1616) succeeded Fabricius as professor of anatomy at the University of Padua and published his own writings regarding technique and equipment for tracheotomy, recommending a curved silver tube with several holes in it. Marco Aurelio Severino (1580–1656), a skillful surgeon and anatomist, performed multiple successful tracheotomies during a diphtheria epidemic in Naples in 1610, using the vertical incision technique recommended by Fabricius.