The Regenerative Effects of Intracordal Injection of Basic Fibroblast Growth Factor for Vocal Fold Scar After Burn or Radiotherapy: A Preliminary Report.

OBJECTIVE

Vocal fold scar secondary to burn or radiotherapy is an intractable condition characterized by severe dysphonia. These scars are highly resistant to conventional treatments due to extensive cellular depletion and fibrosis. This study presents the preliminary results of intracordal basic fibroblast growth factor (bFGF) injection as a regenerative therapy for this challenging pathology.

METHODS

Six patients with severe vocal fold scar (one from burn and five from radiotherapy for head and neck cancer) were treated. Under topical anesthesia, 10 µg of bFGF was repeatedly injected into the vocal folds four times on a weekly basis. Therapeutic outcomes were assessed before and after treatment using maximum phonation time (MPT), the grade-roughness-breathiness-asthenic-strained (GRBAS) scale, the University of Wisconsin Score (UWS), and vocal fold vibratory amplitude (VFVA), which was calculated using stroboscopic images.

RESULTS

All patients completed the treatment protocol without any drug-related adverse events. The therapeutic effects varied among patients, resulting in no significant changes in MPT, UWS, or VFVA, while three cases showed remarkable improvement of vibratory properties with improvement of voice. Overall GRBAS scale showed significant improvement.

CONCLUSIONS

This preliminary report suggests that intracordal bFGF injection may be effective for some cases even with severe vocal fold scar caused by radiotherapy, while the effects for burn-related scar remain unclear. Further investigation in a larger cohort is warranted to explore more information about the therapy.