Voice quality after transoral CO2 laser microsurgery (TOLMS): systematic review of literature

Establishing a Mouse Model of Surgical Vocal Fold Injury

OBJECTIVE

Animal models of vocal fold (VF) surgical injury and scar formation provide insight into the wound healing process. The purpose of this study was to establish an alternative model of surgical injury to the mouse VF using materials commonly available in most research laboratories or for purchase and to investigate wound healing of the epithelium (EP) and lamina propria (LP).

METHODS

Mice were anesthetized by isoflurane gas delivery and positioned on a platform so that the larynx could be observed using a laryngoscope and dissection microscope. Unilateral VF injury was created using a wire brush. Mice were euthanized and the larynx evaluated 1-, 3-, 5-, 7-, 14-, and 28-days following injury. Histological and immunofluorescent analysis was used to evaluate thickness of the EP, LP area, proliferative (Ki67+) and basal cells (p63+) in the EP, and collagen III content in the LP.

RESULTS

The depth of injury reached the superficial thyroarytenoid muscle on Day 1. The thickness of the EP of the injured VF was increased on Days 3 and 5, and the LP area was increased on Days 3, 5, and 7 as compared with the uninjured VF. Ki67+ and p63+ cells were increased on Day 3 and collagen III content was increased on Days 5 and 28 as compared with the uninjured VF.

CONCLUSION

We successfully established an alternative method of creating unilateral VF injury in the mouse. This method will be useful for future research regarding VF surgical injury and wound healing.

LEVEL OF EVIDENCE

NA Laryngoscope, 135:213-222, 2025.

Oncological and Functional Outcomes After Type III Cordectomy for Early Glottic Cancer (Tis, T1a): A Retrospective Study Based on Our 10-Year Experience

Background: The recommended treatment for early glottic cancer is trans-oral laser microsurgery, with excellent oncological and functional outcomes. The aim of this study is to evaluate oncological and functional outcomes in patients who underwent monolateral type III laser cordectomy for early glottic cancer. Methods: A total of 104 patients were enrolled. Staging, histological type, grading, assessment of surgical margins, mean time of relapse, OS, DFS, and DSS were obtained. Maximum phonation time, GIRBAS score, shimmer, jitter, fundamental frequency, and Yanagihara score were evaluated. Patients were submitted to the VHI-10 questionnaire. Results: Correlations between patients with single recurrence and the anterior commissure involvement were analyzed, as well as correlations between patients with recurrence and the status of margins. Correlations between VHI-10 scores and anterior commissure involvement were analyzed. Conclusions: The recurrence rate was higher in patients with anterior commissure involvement. A significant inversely proportional association between DSS and assessment of surgical margins was observed. The distribution of VHI-10 scores differed significatively in patients with and without anterior commissure involvement. Vocal results reflected mild dysphonia.

Factors Impacting Provider Treatment Decision-Making in Early Glottic Cancer

OBJECTIVES

Transoral laser microsurgery (TLMS) and radiotherapy (XRT) are mainstays of treatment for early glottic carcinoma (EGC). Here, we investigated case-dependent provider treatment preferences and identify factors which impact decision-making in EGC.

METHODS

This cross-sectional survey of laryngologists, head-and-neck surgeons, and radiation oncologists presented five diagrammatic cases of progressively advanced EGC (T1/2, N0). Respondents indicated preference for TLMS or XRT and ranked factors which influenced their recommendation for each case. Analysis utilized descriptive statistics, Fischer's exact tests, and Kruskal-Wallis tests for nonparametric data.

RESULTS

A total of 141 complete responses (69.5% laryngologists) were received. Most respondents practiced in academic settings (93.5%) and within multidisciplinary teams (94.0%). Anterior commissure involvement was the most important a priori tumor factor for case-independent treatment recommendation (Likert Scale: 4.22/5), followed by Laterality (Likert Scale: 4.02/5). Across all specialties, TLMS was recommended for unilateral T1a lesions. Laryngologists continued recommending TLMS in T2 lesions (41.0%) more than head-and-neck surgeons (5.0%) and radiation oncologists (0.0%). Across all cases, survival and voice outcomes were the most important clinical factors impacting treatment decisions. Radiation oncologists weighed voice more heavily than laryngologists in more complex presentations of EGC (rank: 1.6 vs. 2.7, Kruskall-Wallis: p < 0.05).

CONCLUSIONS

In more complex clinical presentations of EGC, preference for TLMS compared to XRT differed across specialists, despite similar rankings of factors driving these treatment recommendations. This may be driven by differing experiences and viewpoints on case-dependent voice outcomes following TLMS versus XRT, suggesting a need for increased understanding of how tumor location and depth impact voice outcomes.

LEVEL OF EVIDENCE

5 Laryngoscope, 134:3686-3694, 2024.

[The effect of narrow band imaging in CO2 laser therapy in early-stage glottic cancer]

Objective:To explore efficacy of narrow band imaging（NBI） technique in CO2laser therapy in Early-Stage Glottic cancer. Methods:The clinical data of patients with Early-Stage Glottic cancer who underwent CO2laser vocal cord resection from June 2011 to August 2022 were retrospectively analyzed. Among these, 27 patients who underwent surgery assisted by NBI were assigned to the observation group, while 25 patients who underwent conventional CO2 laser microsurgery with a suspension laryngoscope were assigned to the control group. The differences between the two groups were analyzed in terms of intraoperative frozen pathology results, postoperative recurrence rates, 5-year cumulative disease-free survival rates, complications, and voice recovery. Results:All 52 patients were operated successfully. Temporary tracheostomy and serious complications did not occur during the operation. The postoperative patient's pronunciation was satisfactory. One patient experienced vocal cord adhesion, but there were no severe complications such as breathing difficulties or bleeding, with an overall complication rate of 1.92%. Postoperative follow-up was 1-5 years. The 5 years recurrence free survival in the general group was 77.90％, and the 5 years recurrence free survival in the NBI group was 100％, the difference was statistically significant（P<0.05）. NBI endoscopy is safer and more accurate than the general group in determining the safe margin of tumor mucosal resection（P<0.05）. Among the patients who accepted the voice analysis, the difference was no statistically significant（P>0.05）. Conclusion:Compared with conventional CO2laser surgery under microscope, NBI guided laser resection of Early-Stage Glottic cancer is more accurate. NBI guided laser resection could improve 5 years recurrence free survival rate. In a word, narrow-band imaging endoscopy can has very high value in clinical application.

Application of Platysma Myocutaneous Flap in Surgical Repair after T2-3 Glottic Carcinoma Resection

OBJECTIVE

Numerous methods and materials are available for vertical partial laryngectomy. In this study, the reparative effects of the platysma myocutaneous flap (PMF) and ribbon myocutaneous flap (RMF) on the postoperative voice quality of patients were compared to provide a reference for selecting a method conducive to improving postoperative voice quality.

METHODS

A retrospective analysis was performed on patients with unilateral T2-3 glottic carcinoma. Following vertical partial laryngectomy, the defect was repaired with a PMF or simple RMF. Twelve months after surgery, voice quality was assessed according to voice acoustics, aerodynamics, and subjective perceptual evaluation, and glottic morphology was recorded using a laryngeal stroboscopy.

RESULTS

A total of 70 patients were identified, including 54 in the PMF group and 16 in the RMF group. The PMF group was superior to the RMF group in terms of voice quality assessed by voice acoustics, aerodynamics, and subjective perceptual evaluation. In the PMF group, 72.2% of patients performed phonation with their vocal cords, and approximately 27.8% of patients were affected by supraglottic compression. In the RMF group, 81.3% of patients were affected by supraglottic compression. No significant difference was found in the 5-year survival rate between the two groups.

CONCLUSION

For defect repair following vertical partial laryngectomy, a PMF can allow better postoperative voice quality to be achieved than an RMF because a PMF can provide more tissue (including strap muscle under the flap) for padding, which enables the glottic portion corresponding to the vocal cord to close well.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:3181-3186, 2024.

Injuries of Different Surgical Instruments on the Vocal Folds of Dogs

OBJECTIVE

This study aimed to compare the damage of vocal folds caused by four different surgical instruments: CO2 laser, electrosurgical knife, plasma radiofrequency ablation, and steel knife.

STUDY DESIGN

Randomized controlled study.

METHODS

The CO2 laser, electrosurgical knife, plasma radiofrequency ablation, steel knife, and other instruments were used to simulate the laryngeal microsurgery on experimental dogs. Both total vocal fold resection and punctate ablation were performed. On the day of surgery and 6 days later, the vocal fold tissue from the surgical site was removed for histological evaluation. The extent of vocal fold damage was assessed using the automatic digital pathological scanning system.

RESULTS

We detected varying degrees of damage to the laryngeal tissues. Only the steel knife caused epidermal defects on the vocal fold tissue, while other instruments produced thermal damage of different degrees. Furthermore, the steel knife also showed better and faster healing. The plasma radiofrequency ablation was found to cause more severe thermal burns to vocal folds than other surgical instruments (P < 0.05). Six days postsurgery the inflammatory reaction from the steel knife had basically subsided, with only hyperplasia and tissue repair visible microscopically, showing the best healing degree. On the other hand, the radiofrequency ablation group showed the heaviest inflammatory reaction, indicating relatively poor prognosis (P < 0.05).

CONCLUSION

Compared with the CO2 laser, the electrotome and steel knife showed less damage and better healing, while the plasma radiofrequency ablation showed the most obvious thermal burns to laryngeal and vocal tissues during surgery, with relatively poor healing.

Polycystic Ovary Syndrome and Alteration of Vocal Function: A Systematic Review and Meta-Analysis

INTRODUCTION

Polycystic ovary syndrome (PCOS) is a common hormonal disorder among young women, correlated with hyperandrogenism. Among the symptoms of PCOS, vocal alterations are quite unknown. Dysphonia may be related to hyperandrogenism, and there is no consensus about its prevalence and the severity of vocal disorders, which can cause noticeable discomfort.

METHODS

A systematic review of the literature was conducted. Four studies on PCOS that evaluated the phonatory system were included for a total of 174 patients (96 PCOS, 78 controls), and a meta-analysis on comparable data was performed.

RESULTS

Four studies evaluated parameters related to vocal symptomatology, altered audiometric examination, and findings at the laryngoscopy in patients affected by PCOS versus controls. Although the individual studies showed increased incidence of alterations and a tendency to develop speech fatigue in women with PCOS, when the results of studies were pulled in meta-analysis, the overall difference was not statistically significant. The studies themselves were very different from each other; therefore, it is hard to draw any firm conclusions.

DISCUSSION

The aim of this study was to assess the prevalence of vocal alterations, the correlation with hyperandrogenism, the quality of life, and the voice changes after starting a therapy for PCOS. The present meta-analysis failed to find any difference in terms of PCOS and control cohort. However, the lack of high-quality studies makes it difficult to draw firm conclusions. New and larger studies or big population program data are therefore warranted.