Effect of mitomycin-C on vocal fold healing in a canine model.
For evaluation of the effect of topical mitomycin-C on vocal fold healing and return of function after surgical excision of mucosa, 6 dogs underwent suspension microlaryngoscopy with bilateral microflap excision of vocal fold mucosa. Topical mitomycin-C, a chemotherapeutic agent and a fibroblast inhibitor, was applied randomly to one side, with the contralateral side serving as the control. Laryngeal videostroboscopy (LVS) was performed on each animal before the operation, at 2 weeks, and before sacrifice at 4 weeks. Both functional analysis with LVS and histologic analysis were performed in a blinded fashion to determine the effect of mitomycin-C on healing. Histologic analysis was augmented with computer morphometrics. The LVS revealed diminished mucosal wave vibration in the vocal folds treated with mitomycin-C, as well as a more atrophic appearance to the vibratory surface. The vocal folds treated with mitomycin-C showed fewer fibroblasts and less collagen within the superficial layer of the lamina propria than the control vocal folds (p < .05, Student's t-test, paired analysis). Inflammatory infiltrate was not significantly different between the two sides. Consistent with the known suppression of fibroblast proliferation by mitomycin-C, the treated vocal folds showed less connective tissue response to the surgical injury. In contrast to the reported positive effects of mitomycin-C on tracheal and glottic stenosis, the observed decrease in the healing response in the present study had negative consequences on the vocal fold vibratory pattern.
Garrett
C G
CG
Department of Otolaryngology, Vanderbilt Bill Wilkerson Center for Otolaryngology and Communication Sciences, Nashville, Tennessee, USA.
Soto
J
J
Riddick
J
J
Billante
C R
CR
Reinisch
L
L
D000287:Administration, Topical; D000818:Animals; D000963:Antimetabolites / Q000008:administration & dosage / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D004285:Dogs; D005347:Fibroblasts / Q000473:pathology; D016685:Mitomycin / Q000008:administration & dosage / Q000494:pharmacology*; D014827:Vocal Cords / Q000473:pathology / Q000601:surgery*; D014945:Wound Healing / Q000187:drug effects*
D000963:Antimetabolites; D016685:Mitomycin