Proposed method of intracordal injection and gelation of poly (vinyl alcohol) solution in vocal cords: polymer considerations.

Intracordal polymer solution and/or suspension injection has potential in the swelling of paralysed or partially removed vocal cords to the midline laryngeal position. This technique allows the normally functioning cord to vibrate against the swollen one in order to produce sound. Polymeric systems which may possibly be used for the treatment of vocal cords are presented and analysed with special reference to poly(vinyl alcohol). Aqueous poly(vinyl alcohol) solution in concentrations of 3% to 10% (wt/wt) are gelled by glutaraldehyde. The gelation kinetics are followed and the gelation point, final crosslinking density and structure are determined in terms of the initial molar ratio of crosslinking agent to polymer. The mechanical properties of poly(vinyl alcohol) gels are discussed. Finally a proposed technique for the application of these systems for the treatment of certain vocal cord impairments is presented.