Pitch Changing Surgery
(low to high)

Type IV thyroplasty

This surgery was originally named ‘cricothyroid approximation’. Isshiki invented the surgery for the people who are not able to speak in high pitch because of estrogen / androgen hormone secretion disorder, inappropriate intake of anabolic steroids, superior laryngeal nerve paralysis, etc. Recently, the surgery has been also done for transgender women (MTF).

When we phonate in high pitch the muscle connecting cricoid and thyroid cartilages contract to increase the tension of vocal folds. The surgery substitutes the contraction of the muscle by approximating cricoid and thyroid cartilages.

The surgical procedure is as follows. Following local anesthesia using xylocaine, a 4 to 5 cm incision is made at the front neck to expose the thyroid and cricoid cartilages. The four sutures which connect the cricoid cartilage and the lower edge of thyroid cartilage are made. The voice pitch is tuned higher by pulling the sutures, listening to the voice of a patient. The sutures are tightened at the point that patients feel comfortable with their voice pitch. Speaking is possible following three days of voice rest.

There is another surgical method for raising the voice pitch, Wendler’s glottoplasty which is performed under general anesthesia. The disadvantage of the surgery is that the voice after the surgery is unpredictable and time for recovery takes several months. Therefore, we believe that type IV thyroplasty under local anesthesia is a safe and sure procedure for raising the voice pitch.