An Integrated Experimental-Computational Study of Vocal Fold Vibration in Type I Thyroplasty.

Subject-specific computational modeling of vocal fold (VF) vibration was integrated with an ex vivo animal experiment of type 1 thyroplasty to study the effect of the implant on the vocal fold vibration. In the experiment, a rabbit larynx was used to simulate type 1 thyroplasty, where one side of the vocal fold was medialized with a trans-muscular suture while the other side was medialized with a silastic implant. Vocal fold vibration was then achieved by flowing air through the larynx and was filmed with a high-speed camera. The three-dimensional computational model was built upon the pre-operative scan of the laryngeal anatomy. This subject-specific model was used to simulate the vocal fold medialization and then the fluid-structure interaction (FSI) of the vocal fold. Model validation was done by comparing the vocal fold displacement with postoperative scan (for medialization), and by comparing the vibratory characteristics with the high-speed images (for vibration). These comparisons showed the computational model successfully captured the effect of the implant and thus has the potential for presurgical planning.

Impact of Wendler glottoplasty on acoustic measures and quality of voice in transgender women: a systematic review and meta-analysis.

PURPOSE: Since new evidence regarding the impact of Wendler glottoplasty (WG) on the voice in transgender women became available in the literature in recent years, we aimed to perform an updated systematic review and meta-analysis to determine the actual safety and efficacy of WG in the process of vocal feminization. METHODS: PubMed, Embase, and Cochrane were searched for English-language articles published until July 4, 2023. Studies were found eligible if they evaluated the impact of WG on the acoustic-aerodynamic measures and quality of voice in transgender women. RESULTS: Twenty-three studies were identified. After exclusion of three studies due to incomplete data, 20 studies including 656 patients were included in the meta-analysis. After WG, there was a significant increase of fundamental frequency, speaking fundamental frequency, and lower limit of the frequency range (p < 0.001). Concurrently, a significant reduction of frequency range and maximum phonation time was observed (p < 0.001). No significant differences were found between the pre- and postoperative values regarding the Grade, Roughness, Breathiness, Asthenia, and Strain scale score (p = 0.339). The overall score in the Trans Woman Voice Questionnaire (TWVQ) significantly improved after WG (p < 0.001). CONCLUSIONS: WG is an effective voice feminization method in transgender women, associated with a high procedural success and low risk of postoperative complications. Significantly improved TWVQ score after surgery suggests its positive impact on the voice-related quality of life. Postoperative decrease of maximum phonation time and frequency range does not seem to significantly impact the effectiveness of voice production.

Long-term voice outcomes of medialization thyroplasty with adjustable implant for unilateral vocal fold paralysis.

OBJECTIVES: Medialization thyroplasty (MT) using various implants has been employed as a corrective procedure for unilateral vocal fold paralysis (UVFP). A newly developed APrevent® vocal implant system (VOIS) offers an innovative solution with a finely adjustable design. This study aimed to investigate the long-term functional voice outcomes and benefits of postoperative adjustments in patients receiving MT using the VOIS-implant. METHODS: This is a prospective case series study at single tertiary medical center. Fourteen adult patients diagnosed with UVFP received MT with the VOIS implant and were followed up for more than 1 year. Implant adjustment procedure by injecting 0.9% physiological saline solution was performed both during and after the surgery to optimize glottal closure and voice quality. Objective voice outcomes and acoustic parameters were assessed preoperatively and postoperatively at various timepoints. RESULTS: Thirteen patients (93%) received intraoperative balloon adjustment, ranging from 0.05to 0.12 ml. Four patients underwent adjustments postoperatively and exhibited a positive trend towards immediately improving acoustic voice quality. Our long-term results demonstrated a notable improvement after the surgery in voice quality, with significant decreases in VHI-30 and improvements in perceptual parameters of GRBAS scale, acoustic measures such as jitter and signal-to-noise ratio (p < 0.001) and cepstral peak prominence smoothed in sustained vowel and short sentences. The voice outcomes remained stable more than 1 year follow-up. CONCLUSIONS: Overall, MT with VOIS implantation provides a favorable long-term outcomes and stability in voice quality for patients with UVFP and also an effective tool for postoperative adjustment without major revision surgeries.

Predictors of injection laryngoplasty volume for glottic insufficiency.

PURPOSE: Volume injected for glottic insufficiency is paramount in achieving desired outcome. Factors that determine the required volume have not been thoroughly investigated and may correlate with outcome. The first objective of this investigation was to evaluate the association between injectable volume and various parameters, including lifestyle characteristics, pre-procedural factors, and voice measures, while the second aim assessed the correlation of volume to clinical outcomes in patients who underwent injection laryngoplasty. METHODS: For the first objective, a one-way ANOVA and univariate linear regression were used to analyze data from 124 patients (injected material, pre-operative diagnosis, previous voice therapy, age etc.). One-sample t-tests and Pearson correlational coefficients were employed for statistical analysis of aim 2 in a subgroup of 28 patients that had pre- and post-injection voice evaluations (e.g., acoustic and aerodynamic analysis, perceptual assessment, questionnaires). RESULTS: Average injection volume was 0.39 ± 0.062 mL (range: 0.1-1.6mL). No pre-procedural or lifestyle factor significantly affected injection volume (p > 0.05). There was no relationship between pre-procedural voice outcomes and injection volume (p > 0.05). Of the factors that were significantly improved post-injection laryngoplasty (GFI, VHI, and GRBAS), there were no significant correlations between the magnitude of improvement in these measures and injection volume (p > 0.05). CONCLUSION: Injection volume does not appear to be affected by pre-procedural or lifestyle factors. In addition, injection volume does not significantly impact clinical outcomes assessed through voice analysis or patient-reported questionnaires. Our results underscore the complexity of factors at play in injection laryngoplasty for glottic insufficiency.

3D-exoscopic microlaryngoscopy in phonosurgery for glottic insufficiency.

PURPOSE: We hypothesized that using a 3D-exoscope (3Dex) in microlaryngoscopic phonosurgery is non-inferior to using a standard operating microscope (OM). To compare the above, we utilized a 3Dex and an OM for microlaryngoscopic vocal fold augmentation with autologous fat in patients with glottic insufficiency and compared the procedure itself and the long-term impact of vocal fold augmentation on subjective and objective voice parameters in both groups. METHODS: 36 patients with glottic insufficiency received microlaryngoscopic laryngeal augmentation with autologous fat. A 3Dex was utilized in 24 cases for visualization and compared to twelve cases in which an OM was used. Voice parameters were evaluated over a period of twelve months. RESULTS: Comparison of operation time and voice parameters between the 3Dex and OM groups did not reveal significant differences. Significant improvement of mean voice quality in all parameters excluding roughness was observed at 3 and 6 months followed then by a slight decrease of voice quality parameters between the 6 and 12 months interval in both groups. CONCLUSION: Our findings indicate no difference concerning operation time and outcome between the use of a 3Dex and an OM in phonosurgery. Our results highlight a significant voice improvement after vocal fold augmentation with autologous fat in glottic insufficiency mediated dysphonia. The smaller viewing system, better ergonomics for the primary surgeon and the assistant and a direct view for the entire surgical team make a 3Dex an interesting alternative for visualization in microlaryngoscopic phonosurgery.

Management of Implant Extrusion following Thyroplasty for Vocal Fold Paralysis: A Case Report.

The most widely used laryngeal surgery technique for patients with vocal fold paralysis is medialization thyroplasty. Materials such as Gore-Tex, silastic, and hydroxyapatite are often used, and the most worrisome possible complication is extrusion of the implant. A 36-year-old female patient with a history of pediatric cardiac surgery was diagnosed with left vocal cord paralysis after an episode of upper respiratory infection with a working diagnosis of subclinical left vocal cord paralysis following cardiac surgery. She underwent medialization thyroplasty with a Gore-Tex implant under local anesthesia. On the 21st postoperative day, she presented with sudden-onset hoarseness and dysphagia due to Gore-Tex implant extrusion. The implant was removed and augmentation of the left vocal cord with adipose tissue was performed. Only 14 cases of Gore-Tex implant extrusion have been described in the literature so far. The aim of this case report was not only to show one possible complication when using a Gore-Tex implant but also to present fat augmentation as one of the solutions for revision medialization and salvage treatment, with sustained long-term results.

Equine laryngoplasty: Effects of three anchoring techniques in the muscular process and three positions for suture implantation in the cricoid cartilage.

OBJECTIVE: To compare the effects of three anchoring techniques in the muscular process and three positions of laryngoplasty suture implantation in the cricoid cartilage on abduction of the arytenoid cartilage and interaction with the cricoarytenoid dorsalis (CAD) muscle compartments. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Twenty-two cadaveric equine larynges. METHODS: Three implantation techniques were assessed in the left muscular process. They were the use of a titanium corkscrew (CS), a standard caudal passage using a Jamshidi needle (JCa), and a standard cranial passage using a Jamshidi needle (JCr). Each was assessed in combination with three caudal locations in the cricoid cartilage (right, left, and left lateral). Each suture combination was tightened to submaximal abduction (Dixon grade 2). Force on the suture, degree of larynx caudal rotation, and CAD muscle indentation were evaluated. RESULTS: The force required for optimal arytenoid cartilage abduction was lower (p < .01) for constructs involving a CS (7.45 ± 4 N). The CS also resulted in lower (p < .01) CAD muscle indentation (2.01 ± 1.25 mm) and less larynx rotation (9 ± 3.87°; adjusted p < .05). CONCLUSION: When inserted into the muscular process at the CAD tendon insertion point, the biomechanical properties of the CS reduced the force required for optimal arytenoid cartilage abduction. The CS also minimized interference with the CAD muscle compartments and reduced caudal displacement of the left arytenoid cartilage when it was under suture tension. CLINICAL SIGNIFICANCE: The CS implantation avoided larynx deformation and muscle interaction, offering the possibility to combine a nerve graft and laryngoplasty as a treatment for recurrent laryngeal neuropathy.

Enhancing prosthesis stability at the cricoid cartilage in equine laryngoplasty using 3-D-printed laryngeal clamps: An ex vivo model study.

OBJECTIVE: To assess a three-dimensional (3-D)-printed laryngeal clamp (LC) designed to enhance the anchoring of laryngeal prostheses at the cricoid cartilage. STUDY DESIGN: Ex vivo biomechanical study. SAMPLE POPULATION: A total of 22 equine larynges. METHODS: Two experimental groups included larynges with standard prosthetic laryngoplasty (PL; n = 10) and larynges with prosthetic laryngoplasty modified with laryngeal clamps (PLLC; n = 10). All constructs underwent 3000 cycles of tension loading and a single tension to failure. Recorded biomechanical parameters included maximum load, actuator displacement, and construct failure. Finite element analysis (FEA) was performed on one PL and one PLLC construct. RESULTS: The maximum load at single tension to failure was 183.7 ± 46.8 N for the PL construct and 292.7 ± 82.3 N for the PLLC construct (p = .003). Actuator displacement at 30 N was 1.7 ± 0.5 mm and 2.7 ± 0.7 mm for the PL and PLLC constructs, respectively (p = .011). The cause of PL constructs failure was mostly tearing through the cartilage whereas the PLLC constructs failed through fracture of the cricoid cartilage (p = .000). FEA revealed an 11-fold reduction in the maximum equivalent plastic strain, a four-fold reduction in maximum compressive stress, and a two-fold increase in the volume of engaged cartilage in PLLC constructs. CONCLUSION: The PLLC constructs demonstrated superior performance in biomechanical testing and FEA compared to standard PL constructs. CLINICAL SIGNIFICANCE: The use of 3-D-printed laryngeal clamps may enhance the outcomes of laryngoplasty in horses. In vivo studies are necessary to determine the feasibility of performing laryngoplasty using the laryngeal clamp in horses.

A systematic review and meta-analysis on the outcomes of type I thyroplasty in the irradiated neck.

BACKGROUND: Type I thyroplasty has been well-documented as a safe and effective treatment modality for vocal fold motion impairment, as well as other select cases of persistent glottic insufficiency. However, history of prior radiation to the neck has traditionally been viewed as a relative, if not formal contra-indication to this procedure. The objective of this systematic review was to analyze all available data in the literature on type I thyroplasty in previously irradiated patients and perform a meta-analysis assessing whether complications and revision rates are significantly different between radiated and non-irradiated patients. Secondary outcomes were to compare voice outcomes between these cohorts. METHODS: Several databases were screened for relevant citations using the PICO process. The quality of studies and risk of bias were evaluated using the MINORS scoring system. Main endpoints for analysis in this study were complication rate and revision rate. Secondary endpoint was reported voice outcome. RESULTS: Three articles were included in the analysis. Zero major complications were reported, including no instances of implant extrusion or explantation. There was an 11.8 % rate of minor complications. There were similar rates of revision between radiation and control groups. There was no significant difference in voice outcomes between groups. The average MINORS score of the studies suggested a high risk of bias. CONCLUSIONS: Based on limited quality evidence, this review suggests that type I thyroplasty is safe and feasible in carefully selected irradiated patients, with comparable complication and success rates as their non-irradiated cohorts. Further large-scale studies are warranted.

Securing injection laryngoplasty with anti-reflux valve.

BACKGROUND: Injection laryngoplasty (IL) is a common procedure performed by the laryngologist to treat glottal insufficiency. It can be performed under general anaesthesia (GA) or as an office-based procedure. One of the common problems faced during IL is the disconnection between the injection needle and injection material syringe due to high-pressure effect. This may lead to leakage of the injectates especially when injecting high-viscosity materials such as calcium hydroxylapatite (CaHa) or injecting through hard fibrotic scar of the vocal fold. PURPOSE: Due to this recurring issue, we propose anti-reflux valve as a connector to link up these two devices. The function of anti-reflux valve is to ensure secure connection between these two devices and overcome the problem. METHODS: The anti-reflux valve that can be used is NeutraClearTM needle-free connector EL-NC1000 or MicroClaveTM clear connector. In our practice, these anti-reflux valves are used together with Integra MicroFrance straight malleable injection needle (0.5 mm diameter, 250 mm length) for IL under GA. However, any other injection needle suitable for IL may also be used with these anti-reflux valves. RESULTS: Our 3 years' experience has shown good outcome with no reported incidence of device detachment or leakage of injectates during IL procedure. CONCLUSIONS: Anti-reflux valve is a readily available device in the operating theatre or clinic and only involve simple preparation prior to IL. It is beneficial as an added device in IL procedure.

Primary injection laryngoplasty after chordectomy for small glottic carcinomas.

OBJECTIVES: The purpose of this study was to analyze the short- and middle-term effects of primary injection laryngoplasty in patients having tumor resection within the same surgery concerning the vocal outcome. Injection laryngoplasty was performed after harvesting autologous adipose tissue via lipoaspiration. METHODS: A prospective study was performed with 16 patients (2 female; 14 male) who received tumor resection and an injection laryngoplasty using autologous adipose tissue during a single stage procedure. Multidimensional voice evaluation including videostroboscopy, patient self-assessment, voice perception, aerodynamics, and acoustic parameters was performed preoperatively, as well as 1.5, 3 and 6 months postoperatively. RESULTS: Results show an improvement in the roughness-breathiness-hoarseness (RBH) scale, voice dynamics and subjective voice perception 6 months postoperatively. Maintenance of Voice Handycap Index, jitter and shimmer could be observed 6 months postoperatively. There was no deterioration in RBH and subjective voice perception 2 and 6 weeks postoperatively. No complications occurred in the fat harvesting site. CONCLUSIONS: Using the lipoaspiration and centrifugation approach, primary fat injection laryngoplasty shows short-term maintenance und middle-term improvement in voice quality in patients with vocal fold defect immediately after chordectomy 6 months postoperatively. Cancer recurrence rate is comparable to the reported cancer recurrence rate for laryngeal carcinoma and thus not elevated through primary augmentation.

A New Technique for Chondrolaryngoplasty in Patients Assigned Female at Birth.

BACKGROUND: Chondrolaryngoplasty is a classical facial feminization surgery for transgender women. In recent years, however, an increasing number of patients assigned female at birth are seeking chondrolaryngoplasty for esthetic purposes. Traditional chondrolaryngoplasty can no longer cope with problems of the growing group whose leading cause of laryngeal prominence differs from the transgender population. METHODS: A modified technique is designed as a supplement to the classical procedure. After the cartilage reduction process, paired platysma flaps are raised and advanced successively, resulting in an overlapped area over the thyroid notch, to further camouflage the thyroid prominence. To evaluate the efficiency of the new technique, a retrospective survey of 34 patients (5 men and 29 women) who underwent the surgery from 2016 to 2021 was performed, via a 5-point Likert scale including 7 questions. Physician assessment was also accomplished to provide an extra estimation. Complications were followed up and analyzed to evaluate the safety of modified surgery as well. RESULTS: Although only half of the patients graded prominence changes more than "moderately changed," as many as 75.0% of them still expressed "completely satisfied" or "satisfied very much" with the outcome. Similarly, physician assessment indicated a satisfactory result in appearance improvement. No severe and irreversible complications occurred after surgery, but lasting scar-related issues were reported by 4 patients and should be paid more attention to. CONCLUSIONS: Generally speaking, the new technique is both safe, efficient, and satisfying for most patients, especially ones assigned females at birth with esthetic demand.

Custom Laser-Cut Silastic® Implants for Type I Thyroplasty in a Preclinical Model.

This study aimed to produce customized silicone elastomer implants of varied size and shape for optimization of type I thyroplasty procedures in a rabbit model. Computer-aided design models of different implant designs were designed and used to program laser cutting of a medical-grade Silastic® sheet. Laser-cut implants were produced rapidly and cost-efficiently. Surgical implantation demonstrated vocal fold medialization and phonation in 5 test subjects. This technique may provide a low-cost alternative or adjunct method to hand-carving or commercial implants.

An Analysis of Postoperative Complications in Medialization Thyroplasty: NSQIP Data.

INTRODUCTION: Medialization thyroplasty is a procedure indicated for treatment of impaired vocal fold movement. The purpose of this study was to identify variables associated with length of hospital stay (LOS), reoperation, and readmission in patients who underwent a medialization thyroplasty procedure for unilateral vocal cord paralysis. METHODS: Adults who underwent unilateral medialization thyroplasty were identified using the 2017 to 2019 NSQIP databases via Current Procedural Terminology code 31591. Data collected included patient demographics, comorbidities, preoperative labs, American Society of Anesthesiologists classification, inpatient status, operative length, and complications. Univariate and multivariate logistic regression were used to analyze effects on total LOS, reoperation, and readmission. RESULTS: 320 patients were identified, with a mean age of 61 years (95% Cl 59.4-62.7) and a female-to-male ratio of 1.1:1. Forty-two (13.1%) patients reported dyspnea as a preoperative symptom. Seven patients (2.2%) reported postoperative complications, 2 with multiple complications: 2 surgical site infections, 2 pneumonias, 2 unplanned intubations, 2 myocardial infarctions, 1 septic shock, 1 cardiac arrest, 1 ventilator use (>48 h), and 1 acute renal failure. Fifty-one (15.9%) were inpatient procedures, with a mean LOS of 1.43 days (95% CI 0.92-1.94). Preoperative functional status and bilirubin were significantly associated with longer LOS (p < 0.001). There were 6 (1.9%) readmissions and 2 (0.6%) reoperations. In univariate analysis, dyspnea varied with reoperation which is important to note in this patient population with glottic insufficiency. CONCLUSION: Medialization thyroplasty is a procedure with a low risk of mortality. However, preexisting patient comorbidities are associated with an increased risk of postoperative complications and an increased length of stay.

Variations in the application of equine prosthetic laryngoplasty: A survey of 128 equine surgeons.

OBJECTIVE: To document variations in the application of equine prosthetic laryngoplasty among equine surgeons. STUDY DESIGN: Cross-sectional survey. SAMPLE POPULATION: Six hundred and seventy-eight equine surgeons performing prosthetic laryngoplasty. METHODS: An online questionnaire was sent to equine surgeons, including diplomates of the American College of Veterinary Surgeons and European College of Veterinary Surgeons. Questions focused on participant profile, surgical technique, antimicrobial therapy, and concurrent procedures. Descriptive statistical analysis was performed on the survey output. RESULTS: Complete responses were received from 128/678 individuals, mostly from experienced surgeons. Most participants used 2 prostheses (106/128, 82.8%) and a single loop was the most common method used to anchor the prosthesis in the cricoid (95/128, 74.2%) and arytenoid (125/128, 97.7%) cartilages. Use of general anesthesia was common, although 46/128 (35.9%) participants now performed most laryngoplasty surgery with standing sedation. The material used as a prosthesis varied among surgeons, although participants typically aimed to achieve grade 2 intraoperative arytenoid abduction. Participants most commonly administered perioperative systemic antimicrobial therapy for 1-3 days (57/128, 44.5%) and 48/128 (37.5%) used local antimicrobial therapy. CONCLUSION: Most surgeons performed laryngoplasty with 2 prostheses, a single loop construct at the muscular process of the arytenoid cartilage and systemic antimicrobial therapy. There was variation in the preferred method of surgical restraint, prosthesis material selection, and use of local antimicrobial therapy. CLINICAL SIGNIFICANCE: Long-established techniques remain popular in clinical practice despite evidence that variations offer advantages, particularly in relation to biomechanics. Other factors are also likely to influence technique selection in a clinical context.

Injection laryngoplasty as an effective treatment method for glottal insufficiency in aged patients.

PURPOSE: The purpose of the study was to assess outcomes of injection laryngoplasty (IL) for treating glottal insufficiency in elderly patients with presbyphonia or unilateral vocal fold paralysis (UVFP). METHODS: A single-center retrospective study was performed. The study group consisted of 34 patients with glottal insufficiency aged between 60 and 82 years who had been treated with injection laryngoplasty. Of them, 16 patients were diagnosed with presbyphonia and 18 with UVFP. RESULTS: After IL, glottal closure improved in both groups. The change was statistically significant in the patients with presbyphonia (marginal homogeneity test MH = 3.80; p < 0.001) and in the UVFP patients (MH = 4.04; p < 0.001). Voice quality improved after IL and 12 months after surgical intervention remained significantly better compared to before augmentation (MH tests were statistically significant at p < 0.05 for R, B, A, and S parameters). In the patients with UVFP, significant improvement was observed in 7 of 12 evaluated parameters (Jitt, RAP, PPQ, Shim, APQ, sAPQ, and NHR) but in the patients with presbyphonia only average fundamental frequency (F0) improved significantly. Comparison of the Voice Handicap Index outcomes before and 12 months after surgery showed improvement of subjectively assessed voice quality in both groups; however, the change was statistically significant only in the UVFP patients. CONCLUSIONS: Injection laryngoplasty is a safe and effective treatment method for glottal insufficiency in the elderly. This study shows a significant and clinically relevant improvement to at least12 months, especially in patients with UVFP.

Endoscopic treatment of paediatric subglottic stenosis and cyst (with video).

OBJECTIVE: The aim of this article is to describe step by step the endoscopic treatment of acquired subglottic stenosis (SGS) in an infant and to show the endoscopic results one month after surgery. STUDY DESIGN: Case presentation with instructional video. SETTING: University Hospital of Verona, Italy. METHODS: We present the case of a 6-month-old ex-26-week preterm female infant who required prolonged intubation in the neonatal period. She referred to our hospital for persistent inspiratory and expiratory stridor, and laboured breathing. The endoscopic dynamic examination of upper airway revealed the presence of type 3 laryngomalacia and subglottic stenosis grade III according to Myers-Cotton classification. An endoscopic balloon laryngoplasty was planned. Two laryngeal dilatations were performed. The endoscopic exploration after the first dilatation showed the presence of a subglottic cyst on the anterior surface of the subglottis. The treatment of subglottic cyst consisted of marsupialization of the cyst with cold microinstruments, and subsequent suction of its content. RESULTS: An endoscopic check-up was carried out one month after surgery. The examination of the upper airway under spontaneous respiration didn't show significant subglottic stenosis. A very small subglottic cyst under the anterior commissure was observed. However, no more balloon dilatations or marsupialization of the cyst were performed in order to avoid the formation of synechiae. CONCLUSION: Treatment of SGS must be planned according to the extent of the stenosis and the history of the patient. Endoscopic procedures, such as balloon dilatation and cyst marsupialization, are best chosen for patients with isolated SGS without prior treatment failure.

Comparison of 24-month voice outcomes after injection laryngoplasty with calcium hydroxylapatite or hyaluronic acid in patients with unilateral vocal fold paralysis.

PURPOSE: The objective was to evaluate the long-term voice outcomes in pa-tients with unilateral vocal fold paralysis treated with injection laryngoplasty using either cal-cium hydroxylapatite (CaHA) or hyaluronic acid (HA). METHODS: A single-centre retrospective study was performed. There were 75 patients with dysphonia due to unilateral vocal fold paralysis: injected with CaHA or injected with HA. We analysed Voice Handicap Index-30 (VHI), videostroboscopic images, auditory-perceptual (GRBAS), and acoustic measures (MDVP) in 6, 12, and 24 months after augmentation. RESULTS: The mean change in VHI 24 months after augmentation was 29.14 in the CaHA group, and 22.88 in the HA group. There was an improvement of glottal gap 6, 12, and 24 months after augmentation in both groups. The GRBAS parameters were similar in both groups throughout the whole period. The MDVP pa-rameters decreased 6 and 12 months after augmentation and were similar in both groups. There were 4 patients augmented with CaHA (12.5%) who needed reintervention within 2 years of surgery and another 4 (9.3%) augmented with HA. CONCLUSION: This study demonstrates that there are no long-term differences in voice outcomes or number of reaugmentations for injection laryn-goplasty with CaHA compared to HA.

Injection laryngoplasty with hyaluronic acid for glottal insufficiency in unilateral vocal fold paralysis: a systematic review of the literature.

BACKGROUND: Glottal insufficiency, mostly caused by unilateral vocal fold paralysis (UVFP) or vocal fold atrophy can be treated by injection laryngoplasty (IL). Materials such as hyaluronic acid (HA) gels are now widely available and used to improve voice quality. Various durability and effects of HA injection laryngoplasties have been reported. The aim of this study is to provide a systematic review of the literature for the use of HA in injection laryngoplasties. METHODS: A systematic literature search was conducted in PubMed and Cochrane Libraries. Three reviewers assessed original research studies concerning vocal fold augmentation with HA for eligibility. English written full-text human studies from 2000 to 2020 with EBM level 1b-2 were included. In vitro studies, animal studies, case reports, case-control studies, correspondence and review articles, and articles with other injection materials were excluded. Demographical data, indication, type of HA, evaluation methods, follow-up, durability of implanted material and complications were assessed. RESULTS: A total number of 311 articles were found in PubMed and Cochrane Library, 13 studies were eligible for final analysis with 1063 patients, mean age of patients was 58.7 years. Main indication for HA IL was unilateral vocal fold paralysis, evaluation methods were subjective-VHI (Voice Handicap Index) questionnaire and objective-acoustic and aerodynamic measurements, mean time of follow-up was 5.9 months. Large-particle HA gels were more favorable for longer durability than small-particle HA, reported time of resorption of HA gels ranges between 6 and 12 months, and complication rate was low. CONCLUSION: Hyaluronic acid injection laryngoplasty increases voice quality, improves results of voice therapy, and can be recommended as overlap treatment before permanent medialization surgery. Compared to other injected materials, HA seems to have more favorable effect on vibratory functions of the vocal folds and thus on the voice quality parameters.

Long-term voice outcomes of laryngeal framework surgery for unilateral vocal fold paralysis.

OBJECTIVE: To evaluate the short- and long-term voice outcomes after unilateral medialization thyroplasty (MT) and unilateral medialization thyroplasty with arytenoid adduction (MT + AA) in patients with unilateral vocal fold paralysis. METHODS: Voice outcomes were assessed preoperatively, and postoperatively at 3 and 12 months according to a standardized protocol. Voice assessment was performed using Voice Handicap Index (VHI), GRBAS Grade, Maximum Phonation Time (MPT), s/z-ratio and subjective numeric rating scales on voice quality, effort, performance and influence on life. RESULTS: Sixty-one patients were included (34 MT and 27 MT + AA). Significant pre- to postoperative improvements were seen in all voice outcome parameters. No significant differences in post-operative values were identified between the groups. CONCLUSION: Based on our findings, we conclude that patients with unilateral vocal fold paralysis who undergo MT and MT + AA achieve comparable and significant long time voice improvement, although voices do not completely normalize. We also conclude that this does not mean that AA is a superfluous procedure, but can indicate the accurate identification of patients in need of the additional AA procedure based on clinical parameters.