MRI evaluation of vocal fold paralysis before and after type I thyroplasty.

Magnetic resonance imaging (MRI) is a useful modality for three-dimensional evaluation of laryngeal anatomy. The authors present data on patients with unilateral vocal fold paralysis both before and after type I thyroplasty for medialization. Videoendoscopic and acoustic measures were obtained. MRI was performed preoperatively and postoperatively. Three-dimensional descriptive parameters were established to assess implant location. As well, vocal and endoscopic assessment were used to determine a successful result. Magnetic resonance images of two patients with satisfactory results were compared with images and vocal analysis of two dissatisfied patients. Use of MRI after type I thyroplasty provides additional information about implant location that can help determine the cause of poor results.