[Clinical study on vocal cords spontaneous rehabilitation after CO2 laser surgery]

To study the spontaneous rehabilitation and phonation quality of vocal cords after different types of CO2 laser microsurgery.

Surgical procedures based on Remacle system Type I, Type II, Type III, Type IV and Type V a respectively. Three hundred and fifteen cases with hoarseness based on strobe laryngoscopy results were prospectively assigned to different group according to vocal lesions apperence,vocal vibration and imaging of larynx CT/MRI. Each group holded 63 cases. The investigation included the vocal cords morphological features,the patients' subjective feelings and objective results of vocal cords.

There are no severe complications for all patients in perioperative period. Vocal scar found in Type I ,1 case; Type II, 9 cases ;Type III, 47 cases; Type IV, 61 cases and Type Va 63 cases respectively after surgery. The difference of Vocal scar formation after surgery between surgical procedures are statistical significance (χ2 = 222.24, P < 0.05). Hoarseness improved after the surgery in 59 cases of Type I , 51 cases of Type II, 43 cases of Type III, 21 cases of Type IV and 17 cases of Type Va. There are statistically significance (χ2 = 89.46, P < 0.05) between different surgical procedures. The parameters of strobe laryngoscope: there are statistical significance on jitter between procedures (F 44.51, P < 0.05), but without difference within Type I and Type II (P > 0.05). This happened in shimmer parameter and the maximum phonation time (MPT) as jitter. There are no statistical significance between Type IV and Type Va on MPT (P > 0.05).

Morphological and functional rehabilitation of vocal cord will be affected obviously when the body layer is injured. The depth and range of the CO2 laser microsurgery are the key factors affecting the vocal rehabilitation.