Vocal Fold Function Research Articles

Does Intralesional Steroid Injection Effectively Mitigate Vocal Fold Scarring in A Rabbit Model?

To assess the efficacy of intralesional steroid treatment in preventing vocal fold scarring following vocal fold surgery using a rabbit model. The research involved 42 male New Zealand white rabbits. Fourteen rabbits underwent vocal fold scar surgery using a 532nm laser and served as controls (control group). The remaining rabbits were divided into two groups of 14: one group received vocal fold scar surgery followed by dexamethasone injection (Dexa group) and the other received the same surgery followed by triamcinolone injection (Triam group). Four weeks after surgery, histological examinations and high-speed video analyses of vocal fold vibration were conducted. The maximum amplitude of vibration was the primary measure for assessing vocal fold function. In addition, real-time polymerase chain reaction (PCR) studies were undertaken to analyze scar regeneration and remodeling. The maximum amplitude differences were notably higher in the Dexa and Triam groups than in controls. Histologically, the collagen density (CD) ratios in both the Dexa and Triam groups were significantly reduced compared with controls. Real-time PCR analysis indicated marked elevations of Has-2 and Mmp-9 in the Dexa and Triam groups relative to controls. Intralesional steroid injections after vocal fold surgery are effective for reducing vocal fold scarring in a rabbit model. NA Laryngoscope, 2024.

Long-term Results of Endoscopic Percutaneous Suture Lateralization for Newborns with Bilateral Vocal Cord Paralysis.

Bilateral vocal fold paralysis (BVFP) is a critical condition in newborns, which may present with significant airway distress necessitating tracheostomy. The purpose of this study is to report the safety and effectiveness of endoscopic percutaneous suture lateralization (EPSL) for newborns with BVFP, and evaluated the long-term results and the stability of the lateralization. A review of patients undergoing EPSL for BVFP at our institutions was performed between October 2018 and June 2023. Preoperative and postoperative clinical information was collected. The functional outcomes of the surgery in terms of breathing, voice, and swallowing were evaluated and recorded. Twenty seven patients were included, with a median age at diagnosis of 12 days (range, 1-33 days). The maximum follow-up is for 5 years. EPSL was successful in 77.8% of cases, effectively avoiding the need for tracheostomy. Dyspnea was relieved within a month after surgery, enabling patients to tolerate oral feeds within 2 months after surgery. Notably, some patients experienced a return of vocal fold function, particularly in successful EPSL cases, underlining the procedure's efficacy. Minor complications, including granulation tissue and wound infection, were observed but were manageable. Major complications were notably absent. The results are durable and stable at long-term follow-up. EPSL for BVFP is a relatively simple, minimally invasive, non-destructive, safe, and effective procedure in newborns, which may avoid the need for a tracheostomy, preserves the laryngeal framework, and does not affect the natural recovery of vocal cords. Level 3: retrospective case series Laryngoscope, 2024.

Contribution of Streptococcus pseudopneumoniae and Streptococcus salivarius to vocal fold mucosal integrity and function.

Structural changes to the vocal fold (VF) epithelium, namely, loosened intercellular junctions, have been reported in VF benign lesions. The potential mechanisms responsible for the disruption of cell junctions do not address the contribution of resident microbial communities to this pathological phenomenon. In this study, we focused on determining the relationship between Streptococcus pseudopneumoniae (SP), a dominant bacterial species associated with benign lesions, and Streptococcus salivarius (SS), a commensal bacterium, with human VF epithelial cells in our three-dimensional model of the human VF mucosa. This experimental system enabled direct deposition of bacteria onto constructs at the air/liquid interface, allowing for the assessment of bacterium-host interactions at the cellular, molecular and ultrastructural levels. Our findings demonstrate that SP disrupts VF epithelial integrity and initiates inflammation via the exported products HtrA1 and pneumolysin. In contrast, SS attaches to the VF epithelium, reduces inflammation and induces Mmp2-mediated apical desquamation of infected cells to mitigate the impact of pathogens. In conclusion, this study highlights the complexity of microbial involvement in VF pathology and potential VF mucosal restoration in the presence of laryngeal commensals.

Solitary Bone Plasmacytoma of the Skull Base With an Unusual Presentation.

Solitary bone plasmacytoma (SBP) is a rare hematological malignancy that usually occurs in the spine and rarely in the skull. It rarely presents in the skull base, but presenting symptoms are associated with cranial nerve involvement depending on the site of the disease. We present the case of a 61-year-old man with an unusual presentation of hoarseness secondary to vocal fold palsy. Imaging showed a large bony lesion in the temporo-occipital region with involvement of the jugular foramen. Further detailed diagnostic procedures confirmed SBP of the skull base. Radiotherapy was given with an uneventful recovery of vocal fold function. Skull base plasmacytoma can be considered as a differential diagnosis of causes of unilateral vocal fold palsy. Early therapeutic management may improve vocal fold function.

Automatic Segmentation of Membranous Glottal Gap Area with U-Net-Based Architecture.

While videostroboscopy is recognized as the most popular approach for investigating vocal fold function, evaluating the numerical values, such as the membranous glottal gap area, remains too time consuming for clinical applications. We used a total of 2507 videostroboscopy images from 137 patients and developed five U-Net-based deep-learning image segmentation models for automatic masking of the membranous glottal gap area. To further validate the models, we used another 410 images from 41 different patients. During development, all five models exhibited acceptable and similar metrics. While the VGG19 U-Net had a long inference time of 1654 ms, the other four models had more practical inference times, ranging from 16 to 138 ms. During further validation, Efficient U-Net demonstrated the highest intersection over union of 0.8455, the highest Dice coefficient of 0.9163, and the lowest Hausdorff distance of 1.5626. The normalized membranous glottal gap area index was also calculated and validated. Efficient U-Net and VGG19 U-Net exhibited the lowest mean squared errors (3.5476 and 3.3842) and the lowest mean absolute errors (1.8835 and 1.8396). Automatic segmentation of the membranous glottal gap area can be achieved through U-net-based architecture. Considering the segmentation quality and speed, Efficient U-Net is a reasonable choice for this task, while the other four models remain valuable competitors. The models' masked area enables possible calculation of the normalized membranous glottal gap area and analysis of the glottal area waveform, revealing promising clinical applications for this model. NA Laryngoscope, 134:2835-2843, 2024.

I-scan combined with laryngovideostroboscopy for predicting malignancy in vocal fold leukoplakia.

This study evaluated vocal fold leukoplakia using i-scan combined with laryngovideostroboscopy for risk assessment prediction. A total of 141 patients with 218 lesions were enrolled in this study. Morphological characteristics of leukoplakia, assessment of the vascular pattern using i-scan, and vocal fold vibratory function were analyzed. The number of patients with no, mild, moderate, severe dysplasia, and invasive carcinoma were 68, 40, 17, 46 and 47, respectively. The sensitivity of morphological characteristic, vascular pattern, vibratory function and predictive model were 77.4%, 72%, 69.9%, and 82.8%, respectively. Receiver operating characteristic curve analysis of morphological characteristic, vascular pattern, vibratory function and predictive model were 0.771, 0.824, 0.769, and 0.923, respectively. The results of logistic regression analysis showed that rough morphological types, perpendicular vascular pattern, severe decrease and absence of mucosal waves increased the risk of malignancy (OR = 5.531, 4.973, and 16.992, respectively; P < 0.001). I-scan combined with laryngovideostroboscopy can improve the differential diagnosis of low-risk and high-risk vocal fold leukoplakia.

Contralateral laryngeal reinnervation in the patient with the right-sided vocal cord paralysis – case-report

Introduction: Paralysis of the nerves supplying the larynx leading to the vocal fold paralysis may have iatrogenic, proliferative, idiopathic or post-traumatic etiology. The most common etiology is iatrogenic, including a complication of the removal of paraganglioma tumors. One of the therapeutic options for vocal cord paralysis in the course of nerve damage is reinnervation of the larynx. One of the most frequently used reinnervation techniques is the anastomosis of the recurrent laryngeal nerve with the cervical ansa, usually ipsilateral or, less often, contralateral. Case presentation: The description concerns a 41-year-old patient with right-sided laryngeal paralysis after removal ofa paraganglioma of the parapharyngeal space, the area of the jugular foramen and the skull base who underwent laryngeal reinnervation using a contralateral cervical ansa. Conclusion: Laryngeal reinnervation procedure involving anastomosis of the recurrent laryngeal nerve with the contralateral cervical ansa allows recovery of the vocal fold function in a situation when the ipsilateral cervical ansa is damaged. This reinnervation involves taking a much longer section of the cervical ansa than in cases of ipsilateral reconstruction. Moreover this method requires creating a tunnel under the prelaryngeal muscles and passing the cervical ansa over the trachea or larynx.

Tension-free thyroidectomy (medial thyroidectomy)-a prospective study: surgical technique and results of 259 operations.

Thyroid surgery is associated with a number of surgical complications including recurrent laryngeal nerve (RLN) injury and hypoparathyroidism. The existing methods share the same principle-the mobilization of the thyroid from the lateral side. The aim of this study was to evaluate the safety of a novel technique of thyroidectomy-tension-free thyroidectomy (TFT) based on the medial approach to the laryngeal nerves and parathyroid glands (PTGs). The study was conducted between August 2021 and July 2022 in Saint Petersburg State University Hospital. A total of 261 patients with thyroid diseases were enrolled in the study and operated on using the TFT technique. The operations with the use of TFT technique were completed in all but two cases which required the conversion to the standard lateral approach. Of 259 TFT cases unilateral laryngeal paresis was registered in 6 (2.3%) cases or in 1.7% of the number of RLNs at risk. In all but one case the vocal fold function recovered in less than 6 months of the follow-up. Among 87 patients who underwent total thyroidectomy transient postoperative hypoparathyroidism was found in 10 cases (11.5%), rate of persistent hypoparathyroidism was 0%. One case of postoperative bleeding was recorded (0.4%). The TFT technique demonstrated high safety and several advantages over the traditional method of performing operations on the thyroid gland.

Development and Application of Automated Vocal Fold Tracking Software in a Rat Surgical Model.

The rat is a widely used model for studying vocal fold (VF) function after recurrent laryngeal nerve injury, but common techniques for evaluating rat VF motion remain subjective and imprecise. To address this, we developed a software package, called RatVocalTracker1.0 (RVT1.0), to quantify VF motion and tested it on rats with iatrogenic unilateral vocal fold paralysis (VFP). A deep neural network was trained to identify the positions of the VFs andarytenoid cartilages (ACs) in transoral laryngoscope videos of the rat glottis. Software was developed to estimate glottic midline, VF displacement, VF velocity, and AC angle. The software was applied to laryngoscope videos of adult rats before and after right recurrent and superior laryngeal nerve transection (N = 15; 6M, 9F). All software calculated metrics were compared before and after injury and validated against manually calculated metrics. RVT1.0 accurately tracked and quantified VF displacement, VF velocity, and AC angle. Significant differences were found before and after surgery for all RVT1.0 calculated metrics. There was strong agreement between programmatically and manually calculated measures. Automated analysis was also more efficient than nearly all manual methods. This approach provides fast, accurate assessment of VF motion in rats with minimal labor and allows for quantitative comparison of lateral differences in movement. Through this novel analysis method, we can differentiate healthy movement from unilateral VFP. RVT1.0 is open-source and will be a valuable tool for researchers using the rat model for laryngology research. NA Laryngoscope, 134:340-346, 2024.

Formation and Assessment of a Laryngology Pathology Video Atlas for Resident Education

Conventional reference images of laryngeal pathologies may provide educational value for Otolaryngology-Head & Neck Surgery (OHNS) residents, but observing dynamic vocal fold function is critical for diagnosis. Our aim was to develop and validate a video atlas of laryngeal pathologies for resident education in OHNS. A multi-institution, prospective case-control study. Ten videos showing 10 representative laryngeal pathologies were verified by two laryngologists. Six videos per category with kappa>0.8 were included in the video database. A collection of the videos was shown to a group of OHNS residents in a quiz fashion to determine if senior trainees would score higher than junior trainees. Another group of residents in OHNS was recruited and randomized to control or intervention. The control group was shown a quiz of 10 laryngeal videos at baseline and 24 weeks later. The intervention group was shown quizzes at baseline and every 6 weeks, ending at 24 weeks. Free-text diagnoses were scored for accuracy. Descriptive statistics, two-tailed tests, and analysis of covariance were performed. Twenty-nine residents participated, with 14 (48.3%) randomized to control, and 15 (51.7%) to the intervention. The postgraduateyear (PGY) level had a significant impact on diagnostic performance. PGY1 and 2 had a significantly lower score than PGY5 (P=0.017 and P=0.035, respectively). PGY3 and PGY4 scores were not statistically different from PGY5 scores. The mean score difference between groups decreases as the PGY level increases (mean difference between groups=0.87, P=0.153), but this was not significant. The current study has created a validated collection of videos that are representative of common laryngeal pathologies and can be easily incorporated into resident video-based learning. Future directions include larger multi-site studies to further elucidate whether repeated viewing of this video atlas can improve OHNS resident laryngology knowledge.

Direct Transvestibular Feminization Thyroid Laryngochondroplasty.

Feminization laryngochondroplasty (FLC) methods have evolved from using a midcervical incision to a submental, less visible incision. The scar may be unacceptable to the patient because it signals gender reassignment surgery. An endoscopic transoral approach to FLC inspired by transoral endoscopic thyroidectomy was recently suggested to avoid the neck scar; however, it requires special equipment and has a long learning curve. A vestibular incision is used to approach the chin in lower-third facial feminization surgery. The authors propose that this incision may be extended to the thyroid cartilage in performing direct FLCs. The authors describe their experience with a novel, minimally invasive, direct transvestibular use of the chin-reshaping incision. The medical records of all patients who underwent direct transvestibular FLC (DTV-FLC) from December of 2019 to September of 2021 were retrieved and reviewed for this retrospective cohort study. Data on the operative, postoperative, and follow-up courses, complications, and functional and cosmetic results were retrieved. Nine transgender women were included. Seven DTV-FLCs were performed during lower-third facial feminization surgery, and two were isolated DTV-FLCs. One was a revision DTV-FLC. Transient minor complications were encountered and resolved by the postoperative visit at 1 to 2 months. Vocal fold function and voice quality remained intact. Eight available patients were satisfied with the surgical results. A blinded assessment by eight plastic surgeons determined that seven procedures were successful. The novel DTV-FTLC approach either in isolation or as part of lower-third facial feminization surgery facilitated scar-free FLC with satisfactory cosmetic and functional results. Therapeutic, IV.

High-Speed Videoendoscopic and Acoustic Characteristics of Inspiratory Phonation.

Given the importance of inspiratory phonation for assessment of vocal fold structure, the aim of this investigation was to evaluate and describe the vocal fold vibratory characteristics of inspiratory phonation using high-speed videoendoscopy in healthy volunteers. The study also examined the empirical relationship between cepstral peak prominence (CPP) and glottal area waveform measurements derived from simultaneous high-speed videoendoscopy and audio recordings. Vocally healthy adults (33 women, 28 men) volunteered for this investigation and completed high-speed videoendoscopic assessment of vocal fold function for two trials of an expiratory/inspiratory phonation task at normal pitch and normal loudness. Twelve glottal area waveform measures and acoustic CPP values were extracted for analyses. Inspiratory phonation resulted in shorter closing time, longer duration of the opening phase, and faster closing phase velocity compared to expiratory phonation. Sex differences were elucidated. CPP changes for inspiratory phonation were predicted by changes in the glottal area index and waveform symmetry index, whereas changes in CPP during expiratory phonation were predicted by changes in asymmetry quotient, glottal area index, and amplitude periodicity. Vocal fold vibratory differences were identified for inspiratory phonation when compared to expiratory phonation, the latter of which has been studied more extensively. This investigation provides important basic inspiratory phonation data to better understand laryngeal physiology in vivo and provides a basic model from which to further study inspiratory phonation in a larger population representing a broader age range. https://doi.org/10.23641/asha.22223812.

Studying the glottal vibration onset and offset using laryngeal high-speed videoendoscopy in connected speech

Laryngeal high-speed videoendoscopy (HSV) is a powerful tool to study the detailed vibratory characteristics of the vocal folds. The use of HSV in connected speech enables us to study the transitory behaviors of the vocal folds during different vocalizations. The onset and offset of voicing contain critical information about the health and function of the vocal folds. In this work, HSV is used to study how the voicing begins/ends at the laryngeal level at the onset/offset of phonation. HSV data were obtained during production of connected speech from participants with non-pathological voices and patients with different neurogenic voice disorders. The data collection was performed using a Photron FASTCAM mini AX200 high-speed camera coupled with a flexible nasolaryngoscope. The glottal attack time and glottal offset time were measured at the onset and offset of different vocalizations, respectively, from the HSV data. The findings show differences in the onset and offset measures between the two groups of participants. The vocal fold vibratory behaviors will be discussed qualitatively and quantitatively using these measures. The use of HSV in connected speech could help us develop accurate voice assessment procedures to assess the vocal folds function during connected speech.

Outcomes of endoscopic percutaneous suture lateralization for neonatal and infantal bilateral vocal ford paralysis.

Bilateral Vocal Fold Paralysis (BVFP) is a rare but significant resource of respiratory distress in neonates and infants. The objective of this study was to evaluate the efficacy and functional outcomes of Endoscopic Percutaneous Suture Lateralization (EPSL) for the treatment of BVFP in neonates and infants. A case series study of nine patients undergoing EPSL for BVFP between January 2019 and June 2021 was conducted. All patients were candidates for tracheostomy prior to EPSL. Demographic features including gender, age at diagnosis and surgery, main symptoms, airway comorbidities, airway support, and etiology were collected preoperatively. Patients were evaluated for breathing, swallowing and phonation postoperatively. Surgical success was defined as the ability to avoid tracheostomy. Functional Endoscopic Evaluation of Swallowing (FEES) was conducted to identify aspiration. Voice evaluation was based on clinical observation. Nine patients underwent ten EPSL procedures (one in the left vocal fold, and nine in the right vocal fold). Eight patients (8/9) were able to successfully avoid tracheostomy and feed orally without aspiration after the procedure. One patient experienced clinical improvement in respiratory support requirements and underwent laparoscopic nissen and gastrostomy tube placement. At the last follow-up, two patients regained normal voice, two patients had mild dysphonia, and five patients had moderate dysphonia. Five patients showed partial return of the contralateral vocal fold function. EPSL is an effective and safe treatment for neonatal and infantal BVFP, which enables patients free from tracheostomy without significant impact on swallowing function or phonation. Level 4.

Localization and quantification of glottal gaps on deep learning segmentation of vocal folds

The entire glottis has mostly been the focus in the tracking of the vocal folds, both manually and automatically. From a treatment point of view, the various regions of the glottis are of specific interest. The aim of the study was to test if it was possible to supplement an existing convolutional neural network (CNN) with post-network calculations for the localization and quantification of posterior glottal gaps during phonation, usable for vocal fold function analysis of e.g. laryngopharyngeal reflux findings. 30 subjects/videos with insufficient closure in the rear glottal area and 20 normal subjects/videos were selected from our database, recorded with a commercial high-speed video setup (HSV with 4000 frames per second), and segmented with an open-source CNN for validating voice function. We made post-network calculations to localize and quantify the 10% and 50% distance lines from the rear part of the glottis. The results showed a significant difference using the algorithm at the 10% line distance between the two groups of p < 0.0001 and no difference at 50%. These novel results show that it is possible to use post-network calculations on CNNs for the localization and quantification of posterior glottal gaps.

Effect of mouse nerve growth factor combined with the exposure of the external branch of superior laryngeal nerve on voice changes after thyroidectomy: a prospective non-randomized controlled trial.

The superior laryngeal nerve (SLN) injury may also affect vocal fold function and voice quality. It is efficient yet simple approach to expose the external branch of the superior laryngeal nerve (EBSLN). Neurotrophic agent mouse nerve growth factor (mNGF) to treat patients after thyroid surgery, and found it had significant efficacy in improving the voice of patients. However, the potential effectiveness and safety of mNGF combined with EBSLN were unclear. In this study, 96 patients who suffered from hoarseness after thyroidectomy at Hangzhou First People's Hospital between January 2018 and October 2019 were screened and divided into the control group and the observation group by patients' choice. In the control group, the SLN was not exposed. In the observation group, the SLN was exposed. The mNGF treatment was administered for observation group once a day at 20 µg each time for 4 weeks. The data of acoustic voice indicators was analysis by univariate analyses. Patients in both groups were followed up for more than 6 months. The rate of SLN damage was compared between two groups. The baseline clinical characteristics of the two groups showed no statistic difference. The results showed that the fundamental frequency was significantly lower 1 month after surgery than 3 days after surgery in both groups. The fundamental frequency perturbation, shimmer, maximum phonation time, highest fundamental frequency, and dysphonia severity index in 1 month after surgery were significantly higher than they were 3 days after surgery (all P<0.001). There was no significant difference in the postoperative harmonic-to-noise ratio between the 2 groups (P=0.426). MNGF combined with the exposure and protection of the EBSLN effectively may prevent voice damage after thyroid surgery.

PSAT383 Tension-free Thyroidectomy in the Treatment of Thyroid Cancer and Follicular Neoplasia: Experience of the First 100 Cases

Abstract Background and aims. The safety of thyroid surgery in terms of recurrent laryngeal nerve palsy and hypoparathyroidism was increasing in the last decade. In this study, we present a new method of tension-free thyroidectomy (TFT), which could be used to further decrease the complication rate after thyroidectomy. Patients and Methods The procedure is based on the medial approach to the recurrent laryngeal nerve and the parathyroid glands after the division of isthmus and successive total dissection of Barry ligament. One hundred consecutive patients (128 nerves at risk) underwent "tension-free thyroidectomy" (TFT) from August to November 2021 performed by one surgeon. There were 80 females and 20 male patients (ratio 4: 1) with a mean age of ninety-two 46,4 (range from 17 to 75). Lobectomy was carried out in 74 (74%) patients, total thyroidectomy in 26 (26%). In 42 cases patients additionally underwent central or/and lateral neck dissection. Indications for surgery were papillary carcinoma (N=52), medullary cancer (N=2), follicular neoplasia - Bethesda IV group after fine-needle biopsy (N=46). Mean thyroid nodule size was 25,3 mm (ranged 7 - 120 mm). Intraoperative transient neuromonitoring was used in all the cases (5 mA), in 20 cases permanent neuromonitoring was also used. Translaryngeal untrasound or direct laryngoscopy were routinely used prior and after surgery to evaluate vocal cords mobility. Calcium and parathormone level were measured in patients after thyroidectomy on the first, 14th and 30th postoperative days. Results The mean operating time of lobectomy was 80±39 (range: 25-120), for total thyroidectomy 80 ±36 (range: 55-130). There was no conversion to the conventional lateral-to-medial approach. No fluctuation of electric activity of laryngeal nerves during surgery was revealed. Intraoperative loss of signal (LOS) due to thermal effect of electrocautery and subsequent transient unilateral laryngeal nerve palsy occurred in 3 cases (2,3% from the total number of nerves at risk). In all these patients normal vocal fold function was confirmed on the 30th day after surgery. No permanent nerve palsy cases revealed. Three patients (out of 26 in the total thyroidectomy group – 11,5%) exhibited a decrease of parathyroid hormone level on the postoperative day 1 which was resolved in two weeks under the substitution therapy with calcium and alfacalcidol. No cases of permanent hypoparathyroidism occurred. Conclusion TFT (tension-free thyroidectomy) can be considered a safe and feasible operation in patients with thyroid cancer and follicular neoplasia. Larger and comparative (randomized) studies with conventional dissection technique should be performed to investigate the hypothesis that this approach can provide a lower complication rate. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

IMPACT OF HIGH-FLOW NASAL CANNULA THERAPY ON SWALLOWING: A PROSPECTIVE COHORT STUDY

IMPACT OF HIGH-FLOW NASAL CANNULA THERAPY ON SWALLOWING: A PROSPECTIVE COHORT STUDY

Preliminary dynamic observation of wound healing after low-temperature plasma radiofrequency ablation for laryngeal leukoplakia

Background Low-temperature plasma ablation (LTPA) is an emerging technique for laryngeal leukoplakia (LL). Objective To initially observe the healing process of trauma after LTPA for LL. Materials and methods Seventeen patients who underwent LTPA for LL were collected, and the degrees of wound healing were analyzed. Results Only 1 patient in who dysbiosis of the pharyngeal flora was induced by self-administered hormone nebulization treatment during the follow-up period. In the remaining patients, the wound healing was characterized by a crater-shaped defect on the vocal folds surface with pseudo-membranes, congestion, and mild edema on postoperative day 1. These symptoms became worse on postoperative day 7. On postoperative day 15, the pseudo-membrane was fully formed and some patients had granulomatous swelling of the vocal cords. These symptoms became better and better on postoperative day 30 and day 45. On postoperative day 60, the mucosa of the vocal folds had essentially returned to normal. On postoperative day 90, the vocal folds morphology and function had recovered well. Conclusion It takes 2–3 months for the wound to heal completely after LTPA for LL. Significance A proper understanding of the wound healing process can reduce unnecessary surgical and pharmacologic interventions and avoid excessive treatment.

Correlation Between Detection Results of Pepsin in Vocal Fold Polyp Tissues and the Postoperative Efficacy

To explore the correlation between detection results of pepsin in vocal fold polyp tissues and the postoperative efficacy. The clinical data of 112 patients with vocal fold polyp who received surgical procedures in our hospital from June 2019 to March 2021 were retrospectively analyzed. The vocal fold morphology and vocal acoustic function were assessed at postoperative week 12. Using binary logistic regression, we explored whether the factors, ie, detection result of pepsin in vocal fold polyp tissue, microscopic suturing, the use of CO2 laser, and the history of smoking, affected the postoperative morphological repair of vocal fold polyps. Then, to observe and compare the influence of the detection results of pepsin on the recovery of vocal acoustic function, we divided the enrolled patients into the pepsin group and the pepsin-free group based on the postoperative detection results of pepsin in the polyp tissues by immunohistochemistry, RESULTS: In the 112 patients with vocal fold polyps, positive staining of pepsin in the postoperative samples was found in 76 patients (67.86%) and negative in 36 (32.14%). Totally 80 patients returned to normal in vocal fold morphology, among whom 32 (88.89%) were in pepsin-free group and 48 (63.16%) in pepsin group. Binary logistic regression showed that pepsin was a clinically significant indicator that affected the postoperative morphological recovery of the vocal fold (P = 0.003). Although hoarse voice was improved in all patients at postoperative week 12, the differences were statistically significant in the proportion of patients with grade, roughness, breathiness, asthenia, strain class G, voice handicap index, maximum phonation time, Jitter, Shimmer and noise-to-harmonic ratio between the pepsin group and the pepsin-free group (P < 0.05), with the pepsin-free group being superior to the pepsin group in the improvement of vocal acoustic function. Pepsin in vocal fold polyps is a clinically significant indicator affecting the postoperative morphological recovery and acoustic efficacy, and patients with negative pepsin are superior to those with positive pepsin in the postoperative recovery of vocal fold morphology and function.