Cricothyroid approximation raises the vocal pitch by simulating contraction of the cricothyroid muscle with sutures. The aim of this study was to determine the role of spiral CT in patients scheduled for cricothyroid approximation. 29 transsexual patients were examined with spiral CT prior to and after laryngoplastic surgery. CT findings were correlated with phonographic findings in all patients. The average reduction of the cricothyroid distance was 6 mm (range 2-10 mm). Vocal pitch elevation was greatest in patients with the largest reduction of the cricothyroid distance. CT accurately determines the cricothyroid distance prior to and after surgery and is an ideal method for follow-up, especially in post-operative reversion towards a lower pitch. In addition, CT provides important data in determining the most appropriate extent and site of intracordal intervention to achieve a desired pitch elevation.