OBJECTIVETo determine the consistence of the parameters related to type I thyroplasty measured by laryngeal specimens and CT scan.

METHODSThe related parameters of 50 laryngeal specimens (unilateral) obtained following total laryngectomy were measured postoperative immediately, and compared with those measured by spiral CT scan with multiple plain reconstructive (MPR) technique preoperatively. Comparative results were analyzed to evaluate the statistical significance between these two methods.

RESULTSThere were no significant statistical differences among the 6 parameters between two methods (P > 0.05), and the results (x +/- s) measured by CT scan and laryngeal specimens showed that the length of the thyroid notch to the inferior thyroid border were (20.7 +/- 1.7) mm and (20.6 +/- 1.7) mm; the length of the vocal cord were (17.3 +/- 1.8) mm and (17.3 +/- 1.8) mm; the length of the oblique line were (28.6 +/- 3.2) mm and (29.1 +/- 2.7) mm; the length of the presumptive horizontal line were (26.2 +/- 2.0) mm and (26.2 +/- 2.0) mm; the endolaryngeal vertical length of the anterior of the vocal cord to the presumptive horizontal line were (4.5 +/- 0.6) mm and (4.5 +/- 0.7) mm; the endolaryngeal vertical length of the vocal process to the presumptive horizontal line were (10.8 +/- 1.1) mm and (10.9 +/- 1.1) mm, respectively. As a result, the endolaryngeal anterior and posterior width of the wedge inserted in the thyroid cartilage were 4 - 5 mm and 8 - 9 mm respectively.

CONCLUSIONSMPR technique of spiral CT scan is able to design the size of the window and the prosthesis of type I thyroplasty preoperatively, which was testified to be a precise and reliable method to measure the larynx.