Treatment of vocal fold scar by carbon dioxide laser and collagen injection: retrospective study on 12 patients

Vocal fold scars are the result of injury to the vocal fold lamina propria. This condition leads to an impaired vibration and usually to poor voice quality. The purpose of our study was to compare the pre- and posttreatment voice assessment scores in patients treated by CO₂ laser-assisted freeing of the scar followed by collagen injection. A group of 12 patients (10 women and 2 men) with vocal fold scars was studied retrospectively. Voice assessment was based on stroboscopy and on perceptual scores using the Grade (G) of the GRABS scale, subjective evaluation by the use of the Voice Handicap Index (VHI), aerodynamic measurements [maximum phonation time (MPT) and phonation quotient (PQ)], and acoustical measurements (frequency range and low intensity). Stroboscopy showed an improvement on the mucosal vocal fold wave and on the glottic competence. The mean VHI was improved from 63.16 to 45.5; G from 2 to 1.41; MPT from 7.05 to 8.62 s; and PQ from 463.02 to 358.54 ml/s. CO₂ laser freeing of vocal fold scars followed by collagen injection, combined with speech therapy, improved significantly the aerodynamic parameters (efficiency of voice), but not the acoustical scores.