Histology of Isshiki thyroplasty type I

Isshiki thyroplasty type I, an open surgical procedure to medialize the true vocal cord, has been proposed as an alternative to Teflon injection in selected cases of recurrent nerve paralysis or vocalis muscle atrophy. This operation was performed in a man with a mediastinal tumor and a paralyzed vocal cord in an intermediate position. He died 1 month later, and his larynx and recurrent nerve were studied histologically. The gross and microscopic changes in the larynx caused by this operation are discussed, and the pathologic changes in the recurrent nerve leading to the paralysis are examined.