Evaluation Of Voice Quality Variation Before And After Surgery For Vocal Cord Precancerous Lesions And Early Stage Of Glottic Carcinoma

Objective:To discuss and compare the changes of voice quality of patients who undergo different operations for vocal cord precancerous lesions and early stage of glottic carcinoma.Methods:During September 2018 to March 2019,70 patients with early stage of glottic carcinoma or precancerous lesions of vocal cord were selected as the case group.According to the pathogenic condition,five different methods of minimally invasive surgery of vocal cord were respectively operated,and the patients were divided into five groups by operation types.Subjective and objective examinations were taken one day before and one month after the surgery,including computerized acoustic analyses of voice[to obtain acoustic parameters:Fundamental frequency（F₀）,jitter,shimmer,noise-harmonic ratio（NHR）],aerodynamics examination[to obtain parameters:maximum phonation time（MPT）,maximal loudest phonation time（MLPT）],vocal cords morphological examination via strobolaryngoscope,subjective assessment of voice[to obtain voice handicap index（VHI）].At the same time,15 normal volunteers were selected as the control group.The results of acoustic analysis,aerodynamics examination and subjective assessment between before and after operation were compared in different groups.Results:The acoustic analysis of voice before and after operation showed that jitter,shimmer and NHR of patients after Group I operation were significantly lower than those before operation（P<0.01）,and MPT,MLPT increased after operation（P<0.05）;jitter,shimmer and NHR showed no significant difference before and after the Group II operation,but MPT and MLPT increased obviously（P<0.05）;after Group III operation,only F₀ increased significantly（P<0.05）;after Group IV operation,F₀,jitter,shimmer and NHR all largely increased（P<0.05）,and MPT,MLPT shortened largely（P<0.01）;after Group Va operation,F₀ increases,jitter（P<0.05）,shimmer and NHR increased significantly（P<0.01）,but MPT was shorter than that before operation（P<0.01）.Comparing with the control group,jitter,shimmer and NHR of patients in 5case groups before operation all apparently higher than those of the control group（P<0.05）,but MPT was shorter than that in control group（P<0.05）.According to multiple comparison,jitter,shimmer and NHR of patients before Group Va operation were higher than those in other case groups（P<0.05）,and MPT was apparently shorter than that in others（P<0.05）.The MPT of patients in 5 case groups after operation were shorter than those of control group（P<0.05）,as for acoustic analysis parameters,Group III,IV and Va showed higher jitter,shimmer and NHR（P<0.05）,and the acoustic analysis parameters of Group I were basically the same as those of the control group.Only the patients after Group I operation,the total scores of VHI and physiological（P）reduced significantly（P<0.05）.Through sStrobolaryngoscope examination,we found that 8 patients after Group I operation whose mucosal waves of the lesion side returned to normal;the mucosal waves of the lesion side after Group II operation all failed to recover,but the inward-movement of ventricular fold and the closure of glottis showed improvement to some extent;there were 3 patients after Group III operation whose mucosal waves of the lesion side vocal cord returned to normal,and 5 patients showed pseudomembrane after the operation;all the patients after Group IV and Va operation,we found that their glottis closure cannot be closed completely,disappearance of the mucosal waves of the lesion side,and the loss of vocal cord structure,scar generation,pseudomembrane and granulation formation which can be observed under laryngoscope.Conclusion:（1）The larger the surgical scope is,the more obvious the influence on F₀ will be.The surgical scope is positively correlated with the increase of F₀.（2）It is very important to make an overall preoperative assessment,and then choose the most suitable surgical way for the patients to recover the voice quality after operation.