Type I thyroplasty is for -

Type 1: Medial displacement of vocal cord (done by injection of gel foam/Teflon paste) Type 2: Lateral displacement of the cord (done to improve the airway). Type 3: Shortening (relax) the cord, to lower the pitch (gender transformation from female to male). Type 4: Lengthening (tightening) the cord, to elevate the pitch (gender transformation from male to female).