Safety and short-term outcomes of basic fibroblast growth factor injection for sulcus vocalis

Glottic insufficiency caused by vocal fold atrophy with or without sulcus: systematic review of outcome measurements

PURPOSE

Identifying outcome measurements instruments (OMIs) to evaluate treatment efficacy in patients with vocal fold atrophy and/or sulcus.

METHODS

Systematic review of records published before March 2021 by searching Pubmed and EMBASE. Included studies reported on adults (> 18 year) with dysphonia caused by glottic insufficiency due to vocal fold atrophy with or without sulcus, who were enrolled into a randomized controlled trial, a non-randomized controlled trial, a case-controlled study or a cohort study. All included studies described an intervention with at least one outcome measurement.

RESULTS

A total of 5456 studies were identified. After removing duplicates, screening title and abstract and full text screening of selected records, 34 publications were included in final analysis. From these 50 separate OMIs were recorded and categorized according to the ELS protocol by DeJonckere et al. (Eur Arch Otorhinolaryngol 258: 77-82, 2001). With most OMIs being used in multiple studies the total number of OMIs reported was 265. Nineteen (19) individual OMIs accounted for 80% of reports. The most frequently used OMIs according to category were: VHI and VHI-10 (subjective evaluation); G of GRBAS (perceptual evaluation); F0, Jitter and Shimmer (acoustic evaluation); MPT and MFR (aerodynamic evaluation) and glottic closure and mucosal wave (endoscopic evaluation). Of these OMIs VHI had a high percentage of significance of 90%.

CONCLUSION

This systematic review identifies the most used OMIs in patients with glottic incompetency due to vocal fold atrophy and/or sulcus as a step toward defining a Core Outcome Set (COS) for this population.

PROSPERO REGISTRATION

238274.

Perceptual, aerodynamic and acoustic outcomes of surgical technique for sulcus vocalis patients: A systematic review and meta analysis

BACKGROUND

Sulcus Vocalis (SV) is a voice disorder characterized by the parallel invagination of the vocal fold epithelium that adheres to the vocal ligament. This condition disrupts the vibratory function, leading to glottal incompetence, hoarseness, and vocal impairment. Despite various proposed surgical techniques, a standardized treatment approach remains elusive.

METHODS

We conducted a comprehensive search across PubMed/Medline, Embase, Web of Science, Scholar, and the Cochrane Library for studies on SV treatment. The inclusion criteria comprised original studies comparing pre- and post-treatment vocal outcomes in SV patients, published in English. We excluded case reports, reviews, studies without continuous data, and patients with vocal scar/atrophy.

RESULTS

Fifteen observational studies were included (361 patients, 53.73 % male, average age 41.64 years). 80 % of these studies employed self-reported outcomes, while 81.25 % analyzed acoustic/aerodynamic data. The follow-up period varied from 4 to 44 months. All techniques significantly improved Voice Handicap Index (VHI) scores (p < 0.001). Dissective and combined techniques exhibited greater reductions in VHI-30/10 (p < 0.001). Maximum Phonation Time (MPT) improved significantly across all techniques (p < 0.001), with dissective techniques demonstrating superior MPT outcomes (p < 0.001). Jitter improved significantly for dissective and injective techniques (p < 0.001), as did Shimmer for all techniques (p < 0.001). Notably, combined techniques displayed the most significant reductions (p < 0.001).

CONCLUSIONS

Surgical treatments significantly improve subjective, aerodynamic, and acoustic outcomes in SV patients. Dissective and combined dissective/injective techniques appear to yield better perceptual and phonatory outcomes compared to injective techniques alone. Further research is necessary to establish the optimal treatment approach for SV.

Predictive Factors Affecting the Outcomes Of angiolytic Laser-Assisted Glottoplasty for Sulcus Vocalis

OBJECTIVE

Glottoplasty using an angiolytic laser is an option for the surgical treatment of sulcus vocalis. In this study, we sought to evaluate the clinical outcomes of using a 532-nm diode laser in sulcus vocalis patients and to identify predictive factors of improved voice outcomes after angiolytic laser-assisted glottoplasty.

METHODS

A total of 66 patients with sulcus vocalis who underwent laser-assisted glottoplasty with a 532-nm diode laser were included in this study.

RESULTS

3 months after surgery, GRBAS scores, patient-reported outcome measures, fundamental frequency (F0), jitter percent, and noise-to-harmonic ratio decreased significantly, while cepstral peak prominence (CPP) of vowel and sentence production increased. Patients with auditory-perceptual improvements showed greater improvement in the Voice Handicap Index (VHI) scores, F0, and CPP of vowel and sentence production compared to those with no improvement. While young male patients with preoperatively high F0 were predicted to have favorable outcomes, the type of sulcus vocalis was not predictive of treatment outcomes. Patients treated with lower laser power showed better improvement in the VHI scores postoperatively than those who received higher laser power per vocal fold. Combined injection laryngoplasty with laser glottoplasty was effective in lowering the F0, especially in male patients with high F0.

CONCLUSION

A 532-nm diode laser is useful for treating sulcus vocalis. Young male patients and individuals with preoperatively high F0 showed better voice outcomes after laser glottoplasty. Laser power and combined injection laryngoplasty are considered to affect improvement in the VHI and lowering F0 after laser glottoplasty in sulcus vocalis.

Vocal fold fibroblasts and exposure to vibration in vitro: Does sex matter?

Studies have shown that certain vocal fold pathologies are more common in one sex than the other. This is often explained by differences in the composition of the lamina propria and anatomical differences between female and male vocal folds, resulting in e.g. different fundamental frequencies. Here, we investigated a potential sex-specific voice frequency effect in an in vitro setting using vocal fold fibroblasts from one male and one female donor with and without cigarette smoke extract (CSE) addition. After exposure to either male or female vibration frequency with or without CSE, cells and supernatants were harvested. Gene and protein analysis were performed by means of qPCR, western blot, ELISA and Luminex. We found that exposure of cells to both male and female vibration pattern did not elicit significant changes in the expression of extracellular matrix-, inflammation-, and fibrosis-related genes, compared to control cells. The addition of CSE to vibration downregulated the gene expression of COL1A1 in cells exposed to the female vibration pattern, as well as induced MMP1 and PTGS2 in cells exposed to both female and male vibration pattern. The protein expression of MMP1 and COX2 was found to be significantly upregulated only in cells exposed to CSE and female vibration pattern. To conclude, different vibration patterns alone did not cause different responses of the cells. However, the female vibration pattern in combination with CSE had a tendency to elicit/maintain more pro-inflammatory responses in cells than the male vibration pattern.

Evaluating Interventions for Sulcus Vocalis or Vocal Fold Scar: A Systematic Review and Meta-analysis

BACKGROUND

Sulcus vocalis reflects varying degrees of vocal cord lamina propria (LP) damage. Many interventions have been discussed in the literature for addressing sulcus vocalis, but there is no universally accepted gold standard for its management.

AIM

We aim in our study to collectively evaluate the effectiveness of different relevant interventions in the literature used for sulcus vocalis or vocal fold scar.

METHODS

We searched five electronic databases to collect all relevant studies. Records were screened for eligibility. Data were extracted from the included studies independently. Our continuous outcomes were pooled in our single-arm meta-analysis as mean change (MC) and with 95% confidence interval (CI).

RESULTS

Our systematic review and meta-analysis included 43 studies encompassing 1302 patients. The jitter parameter indicated that laser degeneration and LP regeneration/scar degradation led to the highest improvements compared to their baseline, with pooled MC of -0.897 and -0.893, respectively. Graft interposition showed a MC of -0.848, while medialization and dissection had less pronounced changes at -0.200. Shimmer parameter results were similar, with medialization and laser degeneration leading to MC of -2.129 and -2.123, while LP regeneration/scar degradation and graft interposition showed smaller changes MC -1.530 and -1.217. For the noise-to-harmonic ratio (NHR) parameter, LP regeneration/scar degradation demonstrated MC = -0.028. In aerodynamics outcomes, graft interposition and LP regeneration/scar degradation showed the highest MCs in mean phonatory time (MPT) (4.214 and 3.467, respectively). Endoscopic outcomes for mucosal wave showed high improvements in medialization and graft interposition (MC = 10.40 and 10.18, respectively). Perceptual outcomes favored graft interposition in various parameters, while laser degeneration performed well in most categories. Graft interposition and LP regeneration/scar degradation had a high voice handicap index (VHI) (MC = -27.195 and -19.269, respectively).

CONCLUSION

Laser degeneration and LP regeneration/scar degradation were particularly effective in improving acoustic parameters. In aerodynamics, graft interposition and LP regeneration/scar degradation improved vocal efficiency compared to their baselines. Medialization and laser degeneration had the largest impact compared to their baseline on shimmer and MPT. Endoscopic assessments showed that medialization and graft interposition had high improvement in mucosal waves, and perceptual outcomes were generally high with graft interposition and laser degeneration.

The use of basic fibroblast growth factor to improve vocal function: A systematic review and meta-analysis

OBJECTIVES

This systematic review and meta-analysis examines if intralaryngeal injection of basic fibroblast growth factor 2 (FGF2) can improve voice outcomes in those with vocal disability.

DESIGN

A Systematic review of original human studies reporting voice outcomes following intra-laryngeal injection of basic fibroblast growth factor 2 in those with vocal dysfunction. Databases searched were Medline (1946-July 2022), Embase (1947-July 2022), Cochrane database and Google Scholar.

SETTING

Secondary or tertiary care centres that undertook the management of voice pathology Hospital.

PARTICIPANTS

Inclusion criteria were original human studies reporting voice outcome measurements following intralaryngeal injection of FGF2 to treat vocal fold atrophy, vocal fold scarring, vocal fold sulcus or vocal fold palsy. Articles not written in English, studies that did not include human subjects and studies where voice outcome measures were not recorded before and after FGF2 injection were excluded from the review.

MAIN OUTCOME MEASURES

The primary outcome measure was maximum phonation time. Secondary outcome measures included acoustic analysis, glottic closure, mucosal wave formation, voice handicap index and GRBAS scale.

RESULTS

Fourteen articles were included out of a search of 1023 and one article was included from scanning reference lists. All studies had a single arm design without control groups. Conditions treated were vocal fold atrophy (n = 186), vocal cord paralysis (n = 74), vocal fold fibrosis (n = 74) and vocal fold sulcus (n = 56). A meta-analysis of six articles reporting on the use of FGF2 in patients with vocal fold atrophy showed a significant increase of mean maximum phonation time of 5.2 s (95% CI: 3.4-7.0) at 3-6 months following injection. A significant improvement in maximum phonation time, voice handicap index and glottic closure was found following injection in most studies assessed. No major adverse events were reported following injection.

CONCLUSIONS

To date, intralaryngeal injection of basic FGF2 appears to be safe and it may be able to improve voice outcomes in those with vocal dysfunction, especially vocal fold atrophy. Randomised controlled trials are needed to further evaluate efficacy and support the wider use of this therapy.

Evaluation of Safety After Intracordal Basic Fibroblast Growth Factor Injection

OBJECTIVES

Although there are many reports of voice improvement with intracordal trafermin (a basic fibroblast growth factor) injections under local anesthesia, few papers have documented the safety of trafermin. Therefore, we aimed to investigate whether trafermin is safer than control drugs (triamcinolone acetonide) early after intracordal injection under local anesthesia.

METHODS

We conducted a retrospective review from the medical records of patients who underwent intracordal injection with trafermin and triamcinolone acetonide under local anesthesia at our institution. Early postinjective complications were defined as changes in vital signs and chief complaints early after intracordal injection.

RESULTS

A total of 699 and 297 patients underwent intracordal injection under local anesthesia with trafermin and triamcinolone acetonide, respectively. Of these, 227 and 130 patients had early postinjective complications with trafermin and triamcinolone acetonide, retrospectively. The most common complications occurring with trafermin was increased blood pressure in 39 cases (5.58%): 17 cases (2.43%) of blood pressure increase of ≥20 mm Hg. Other complications included pharyngeal discomfort in 37 (5.29%), lightheadedness in 33 (4.72%), and phlegm discharge in 29 (4.15%). Triamcinolone acetonide caused pharyngeal discomfort in 28 patients (9.43%), phlegm discharge in 17 patients (5.72%), lightheadedness in 12 patients (4.04%), sore throat in 11 patients (3.70%), increased blood pressure in 10 patients (3.37%): 7 cases (2.36%) of blood pressure increase of ≥20 mm Hg, and dizziness in seven patients (2.36%). Statistical analysis of the complications between trafermin and triamcinolone acetonide showed no significant differences.

CONCLUSIONS

The proportion of early postinjective complications from intracordal injection of trafermin is no significant difference in that of triamcinolone acetonide. The results suggest that the early postinjective complications are not due to the drug action of trafermin, but rather to complications from the intracordal injection procedures. Intracordal trafermin injection may be safe in the short term.

Changes in serum basic fibroblast growth factor concentration following intracordal injection

Objective

Although many studies have reported improvements in voice outcomes with intracordal trafermin injection, there is a lack of data documenting its changes in serum basic fibroblast growth factor (bFGF) blood concentration. This study examined whether serum bFGF concentrations change after intracordal trafermin injection.

Methods

This retrospective study was conducted at Tokyo Voice Center. We investigated serum bFGF concentrations before and after injection in 40 patients who underwent intracordal trafermin injection. There were 26 males and 14 females, with an age ranging from 13 to 88 years (average 53.25 years). They were diagnosed with paralysis (15 patients), atrophy (15 patients), sulcus (8 patients), and others (2 patients: scar and functional), presenting with severe hoarseness that interfered with daily life.

Results

The mean pre- and post-injective serum bFGF concentration of the 40 patients was 6.689 and 4.658 pg/mL, respectively. The difference in mean serum bFGF concentration between pre- and post-injective was -2.031 pg/mL. The Pearson correlation coefficient was calculated to evaluate the correlation between dosage of trafermin and post-injective serum bFGF concentration, and a moderate correlation was found at r = 0.52. Generalized linear model regression analysis was performed for the purpose of adjusting for confounding among variables. The only variable that showed a statistically predominant association with post-injective serum bFGF concentrations was the dosage of trafermin, with an estimated regression coefficient of 0.048.

Conclusion

In this study, the dosage of trafermin we injected and post-injective serum bFGF concentrations were dose-dependent but the amount of changes in the serum bFGF concentration was negligible within the physiological range. Therefore, as with subcutaneous and wound administration, intracordal trafermin injections may be safe.

Level of Evidence

Level IV.

The life-cycle and restoration of the human vocal fold

Objective

To better understand the challenges of designing therapies to treat damaged vocal fold lamina propria, it is essential to understand the biophysical and pathophysiological mechanisms involved in vocal fold development, maintenance, injury, and aging. This review critically analyses these points to try and direct future efforts and new strategies toward science-based solutions.

Data Sources & Review Methods

MEDLINE, Ovid Embase, and Wed of Science databases were used to identify relevant literature. A scoping review was performed following the preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews checklist.

Results

The layered arrangement of the vocal fold, develops during early childhood and is maintained during adulthood unless injury occurs. The stellate cells of the macular flava are likely to be important in this process. The capacity for vocal fold regeneration and growth is lost during adulthood and repair results in the deposition of fibrous tissue from resident fibroblasts. With advancing age, viscoelastic tissue declines, possibly due to cell senescence. Strategies aimed at replacing fibrous tissue within the vocal folds must either stimulate resident cells or implant new cells to secrete healthy extracellular protein. Injection of basic fibroblast growth factor is the most widely reported therapy that aims to achieve this.

Conclusions

The pathways involved in vocal fold development, maintenance and aging are incompletely understood. Improved understanding has the potential to identify new treatment targets that could potentially overcome loss of vocal fold vibratory tissue.

Tissue Engineering as a Promising Treatment for Glottic Insufficiency: A Review on Biomolecules and Cell-Laden Hydrogel

Glottic insufficiency is widespread in the elderly population and occurs as a result of secondary damage or systemic disease. Tissue engineering is a viable treatment for glottic insufficiency since it aims to restore damaged nerve tissue and revitalize aging muscle. After injection into the biological system, injectable biomaterial delivers cost- and time-effectiveness while acting as a protective shield for cells and biomolecules. This article focuses on injectable biomaterials that transport cells and biomolecules in regenerated tissue, particularly adipose, muscle, and nerve tissue. We propose Wharton's Jelly mesenchymal stem cells (WJMSCs), induced pluripotent stem cells (IP-SCs), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), insulin growth factor-1 (IGF-1) and extracellular vesicle (EV) as potential cells and macromolecules to be included into biomaterials, with some particular testing to support them as a promising translational medicine for vocal fold regeneration.

Intracordal injection therapy for vocal fold scarring: Steroid versus basic fibroblast growth factor

Objectives

Vocal fold scarring is caused by replacement of vocal fold mucosa with fibrous tissue due to repeated inflammation or trauma. It can lead to severe dysphonia. It is currently treated conservatively and with phonosurgery and intracordal injections. Intracordal injection of steroid or basic fibroblast growth factor (bFGF) has been recently found to be useful for treating vocal fold scarring that does not respond to voice therapy.

Methods

This retrospective study involved the administration of steroid injection and bFGF injection bilaterally under local anesthesia in 16 patients each. Laboratory measurements of voice parameters were performed before and 3–6 months after injection.

Results

In the steroid injection group, the Voice Handicap Index (VHI) score significantly improved from 57.1 to 40.5, total Grade, Roughness, Breathiness, Asthenia, Strain (tGRBAS) score significantly improved from 4.2 to 2.6, and mean speech fundamental frequency (SFF) increased from 192.5 to 211.4 dB, but there was no improvement in maximum phonation time (MPT) and mean airflow rate (MFR). In the bFGF injection group, significant improvements in the VHI score (from 53.3 to 35.7), MPT (from 16.9 to 21.8 s) and MFR (from 314.6 to 210.5 ml/s) were seen; however, the tGRBAS score did not improve. In addition, the SFF significantly decreased from 178.1 to 160.5 Hz.

Conclusion

These results suggest that both steroid and bFGF injections are effective for treating vocal fold scarring, with steroids improving voice quality and bFGF improving glottic closure, thereby contributing to improvements in VHI scores.

Level of Evidence

4.

Current approaches to management of vocal fold scar

PURPOSE OF REVIEW

Vocal fold (VF) fibrosis remains an insoluble problem in most cases, with a severe impact on vocal quality and effort. This review examines current investigations and research strands that explore the understanding of VF wound healing and applied treatments for the management of VF scar.

RECENT FINDINGS

Recent work focused on VF fibrosis has examined wound healing in the glottis, fibrosis-modifying medication, and tissue engineering approaches that span cytokine and growth factor therapy, scaffold and cell delivery platforms, seeded scaffolds, conditioned media and stem cell therapy. Many show promise and may deliver improvements in the wound bed favouring less fibrogenic healing patterns, ultimately with the goal of preserving or restoring VF vibration. Further collaborative research is required that examines combined approaches, long term outcomes, better three-dimensional modelling of cell-cell interactions and delivery modalities for molecular therapies.

SUMMARY

VF fibrosis research continues to expand and explore a variety of mechanistic pathways in order to understand VF healing and identify novel and complementary targets for manipulation. Many different approaches show promise and may also offer synergistic benefits. Research continues to strive for healing that more closely resembles true VF architecture and function.

[Office-based phonosurgery]

Wesentliche und neue Impulse, die das Behandlungskonzept für ambulante phonochirurgische Eingriffe am unsedierten Patienten betreffen, stammen aktuell aus dem angloamerikanischen Sprachraum. Die dort etablierten „office-based procedures“ werden als eine Alternative zu vielen konventionellen operativen Larynxeingriffen in Vollnarkose propagiert. Maßgeblich für diese Entwicklung ist der Einsatz neuer endoskopischer Techniken in Kombination mit photoangiolytischen Laserverfahren (KTP-Laser und blauer Laser), die eine sichere und effiziente ambulante Phonochirurgie ermöglichen. Die Akzeptanz seitens der Patienten ist hoch, da ambulante Eingriffe als risikoärmer gelten. Ungeachtet der verbreiteten Euphorie fehlen weiterführende Studien, welche die medizinischen Entscheidungskriterien und das Sicherheitsmanagement bei dieser neuen ambulanten Ausrichtung der Kehlkopfchirurgie bewerten.

A Systematic Review on Surgical Treatments for Sulcus Vocalis and Vocal Fold Scar

OBJECTIVES/HYPOTHESIS

Vocal fold sulcus and scars are benign vocal fold lesions that present as a challenge to the laryngologist. A number of different surgical techniques have been proposed, aiming at restoring the lamina propria (LP), closing the glottal gap, or both. This study aimed to provide a systematic review of surgical treatment for sulcus and scar and to propose a new classification for these techniques.

STUDY DESIGN

A literature search using MEDLINE and Google Scholar through August 2020.

METHODS

Data on study design were retrieved and outcomes were classified as acoustic, aerodynamic, self-reported, perceptual, and stroboscopic. Methodological quality was assessed using the MINORs criteria. Each technique was classified as direct, indirect, or combined.

RESULTS

Our search included 31 studies with a total of 617 patients. Direct techniques included dissection, graft interposition, or LP regeneration/scar degradation while indirect techniques aimed for glottal gap closure. Only one article performed a comparison between different types of techniques and only eight studied the five types of outcomes. No superiority of any technique was noted in our analysis. Self-reported outcomes were the most frequently improved.

CONCLUSIONS

There seems to not exist a one-fits-all treatment for this clinical picture and no clear decision-making pattern. A recent trend toward sequential approaches, starting with less invasive procedures, can be observed. Laryngoscope, 2021.

Assessment of Dysphonia Using the Japanese Version of the Voice Handicap Index and Determination of Cutoff Points for Screening

INTRODUCTION

The Voice Handicap Index (VHI) is recognized as a useful subjective assessment method for dysphonia. The original VHI has been translated into numerous other languages, including Japanese (J-VHI). Although the reliability and validity of the J-VHI have already been established, the cutoff point has not been determined. The aims of this study were to investigate the relationship between the J-VHI and other voice laboratory measurements, and determine the cutoff point.

METHOD

This study included 167 dysphonic patients and 55 healthy volunteers. All patients and volunteers completed the J-VHI at the initial visit, and the following outcomes were determined: VHI scores of patients with dysphonia and healthy volunteers, VHI scores according to disease, cutoff point, and correlations between VHI scores and other voice laboratory measurements.

RESULTS

Both the total VHI (VHI-T) and individual domain (functional domain [VHI-F], emotional domain [VHI-E], physical domain [VHI-P]) scores were significantly higher in the dysphonia group compared to the healthy volunteer group. VHI-T, VHI-F, and VHI-E scores were significantly lower in the benign mucosal lesion subgroup, compared to the other disease subgroups. The G scale and B scale of the grade-roughness-breathiness-asthenia-strain scale showed a significant association with VHI-T, VHI-F, and VHI-P scores. Similarly, the A scale showed a significant association with VHI-T, VHI-F, and VHI-E scores. The cutoff point (12) for VHI-T was chosen from the receiver operating characteristic curve to maximize sensitivity and specificity. Similarly, the cutoff points for VHI-F (5), VHI-P (5), and VHI-E (3) were also obtained. Significant differences in maximum phonation time, pitch range, G scale, and B scale were observed between the VHI-T negative (VHI ≤ 12) and positive (VHI-T > 13) groups.

CONCLUSION

These findings suggest that self-evaluation using the VHI could serve as an independent assessment and screening tool for patients with dysphonia.