To describe characteristics of 3-dimensional (3-D) computed tomographic (CT) endoscopic images of the larynx in unilateral vocal fold paralysis and the changes of the paralyzed vocal fold after phonosurgery as indicated by 3-D CT endoscopy.
A university medical center.
Twelve consecutive patients with unilateral vocal fold paralysis who underwent helical CT examination. Five of them underwent the CT examination before and after phonosurgical treatment.
Three patients underwent arytenoid adduction, and 2 underwent type 1 thyroplasty.
Main Outcome Measures
"Sagging," defined as caudal displacement of the vocal fold; and "thinning," defined as a decrease in the vertical thickness of the vocal fold and expansion of the ventricle on the affected side, were evaluated.
Excessive motion artifacts in one patient prevented detailed description of his 3-D images. Sagging and thinning of the vocal fold and expansion of the ventricle on the affected side were noted on 6, 11, and 8 occasions, respectively. Adduction or augmentation of the paralyzed vocal fold after phonosurgery was observed in 3-D CT endoscopic images when displayed with bony densities.
The use of 3-D CT endoscopy enables description of 3-D characteristics of unilateral vocal fold paralysis and supplements stroboscopic findings. Furthermore, CT endoscopic images, when simultaneously displayed with bony densities, may help in evaluating the effects of phonosurgical treatment of the paralyzed vocal fold.