Vocal fold augmentation with calcium hydroxylapatite

Preliminary Results on the Safety and Efficacy of Silk-Hyaluronic Acid for Treatment of Glottic Insufficiency

OBJECTIVES

Silk-Hyaluronic Acid (Silk-HA) is a novel vocal fold augmentation material that has been used in humans since July 2020. There is a paucity of published data on Silk-HA and its longevity remains a question. This study aimed to evaluate a single surgeon's initial experience performing Silk-HA injection laryngoplasty for the treatment of glottic insufficiency.

METHODS

Retrospective chart review of Silk-HA injections between July 2020 and December 2021. Subject demographics, diagnoses, volume of material injected, VHI-10 data, and complications were collected. A blinded perceptual voice analysis of voice samples was performed by two voice-specialized speech-language pathologists (SLP) for a subset of unilateral vocal fold paralysis patients before and 3-months following silk-HA injection. Univariate assessment of the change in VHI-10 and perceptual voice analyses at 3-month follow up was determined.

RESULTS

58 patients (43.1% female) underwent Silk-HA injection with a mean age of 64 (range 21-88). 38 subjects had unilateral paralysis (65.6%), and the remaining had scar, atrophy, paresis or a combination thereof. 49 injections were unilateral (84.5%). Mean volume of silk injected was 0.26 mL. Complications were rare, most notable though for 2 admissions for dyspnea and laryngoscopic evidence of hemi-laryngeal edema (3.4%). Mean change in CAPE-V overall severity rating was -32.9 (P<0.0001), and VHI-10 was -14.6 ± 10 (P=0.0013). 14 patients underwent a repeat silk-HA injection for ongoing glottic insufficiency (loss of augmentation vs under-augmentation).

CONCLUSIONS

Preliminary results for Silk-HA show potential for ongoing improvement of glottic insufficiency at 3 months from date of augmentation. Clinician and patient perception of voice outcomes showed overall improvement at three months, though longevity remains to be determined. While overall well tolerated and without serious complications in 96% of the cohort, patients should be counseled on the potential for airway edema and symptomatic dyspnea requiring steroid management and observation.

Glottal Insufficiency and Parkinson's Disease: A Scoping Review of Vocal Fold Medialization Procedures

OBJECTIVES/HYPOTHESIS

Vocal impairments are early and debilitating symptoms of Parkinson's disease (PD). Glottal insufficiency is a contributor to PD-related dysphonia. Vocal fold injection laryngoplasty (IL) and medialization thyroplasty (MT) are well-established techniques used to restore glottal closure for a range of causes. While use of these interventions to improve vocal function in people with Parkinson's disease (PWPD) has been described in literature, a scoping review of the nature, extent, and duration of benefits of procedural intervention to improve vocal fold closure is warranted to provide insight into patient candidacy for vocal fold medialization procedures in addition to standard PD-specific speech therapy protocols.

STUDY DESIGN

Scoping review.

METHODS

Seven biomedical databases and two gray literature resources were searched to retrieve English-language publications, without restrictions on publication type. Eligibility criteria were diagnosis of participants with PD in adults, presence of a voice concern (eg, dysphonia or glottal insufficiency), and intervention using IL or MT.

RESULTS

The search yielded 174 sources of evidence, 18 of which met inclusionary criteria. In total, 13 publications were research studies, three were reviews, one was a conference proceeding, and one was a book chapter. All available auditory-perceptual, quality of life, acoustic, endoscopic, and safety outcomes were tabulated for case studies and case reports. Studies revealed feasibility, and positive, yet varied, short-term outcomes of IL or MT. The quality of research articles was critically appraised using Joanna Briggs Institute checklists revealing trends of incomplete description of participant demographics, nonconsecutive enrollment of participants, absence of control participants, and lack of validity of several outcome measures.

CONCLUSIONS

Further research, using a rigorous, controlled, blinded, prospective research design to reduce potential bias and improve generalizability of findings is warranted to clarify the benefit of IL and MT, with or without speech therapy, to improve vocal function for PWPD and guide patient selection for vocal fold medialization procedures.

Duration of Effect and Associated Factors of Injection Laryngoplasty

OBJECTIVE

Injection laryngoplasty (IL) has become a mainstay in the treatment of unilateral vocal fold paralysis due to technical ease and avoidance of open surgery. The duration of IL effect depends on the injected material and has not been defined clearly. We aimed to define the effective duration of IL and to investigate the associated factors.

METHODS

Fifty-nine patients who underwent IL for unilateral vocal fold paralysis were included. IL was performed using a cricothyroid membrane approach under local anesthesia. During follow-up, in cases that developed subjective hoarseness with objective glottic insufficiency, a second IL was performed, and loss of IL effect was recorded. The duration of IL was analyzed using Kaplan-Meier estimates, and the associations between duration of effect and various factors such as postinjection voice therapy, injected material, and cause of paralysis were investigated using log-rank test.

RESULTS

Of 59 patients, 20 (33.9 %) received a second IL. The median time interval between the first and second IL was 3.3 months (95% CI, 0.4∼27.8 months). The mean duration of effect after IL was 42.5 months (95% CI, 32.1∼52.9 months), and the rate of persisting effect was 63.4% at 1-year after IL (1-year effect rate) and 59.4% at 2 years after IL. The 1-year effect rate was 80.8% in cases with postinjection voice therapy and 57.8% in those without postinjection voice therapy (P = 0.084). Injected material, DM, HTN, patient age and sex, and cause of paralysis had no effect on the 1-year effect rate.

CONCLUSIONS

The mean duration of IL effect was 42.5 months, and the rate of persisting effect was 63.4% at 1-year after IL. There were no significant factors affecting the duration of effect, although the duration tended to be slightly longer in cases with postinjection voice therapy. Further study with a prospective, randomized design is needed.

Prospective >12 Months Outcomes After Vocal Fold Injection Medialization With Silk Microparticle-Hyaluronic Acid Material

OBJECTIVE

Vocal fold injection medialization (VFIM) is widely used as an initial treatment for unilateral vocal fold paralysis (UVFP). Current practices employ materials that share the limitation of temporary clinical effect from variable resorption rates. A novel silk protein microparticle-hyaluronic acid-based material (silk-HA) has demonstrated cellular infiltration and tissue deposition that may portend a durable medialization effect. We report on ≥12 months outcomes after VFIM with silk-HA.

METHODS

Prospective open-label study of patients with UVFP that elected treatment with VFIM with silk-HA. Blinded experts rated laryngeal stroboscopic exams.

RESULTS

Seventeen patients with UVFP underwent VFIM with silk-HA. Twelve of the 17 patients have ≥12 months follow-up. Seven patients demonstrated durable treatment benefit ≥12 months after injection with median improvement of 19 (p = 0.0156) in VHI-10. There was no significant change in VHI-10 between 1 and 12 months for these patients. Blinded ratings indicated that 5/7 patients with sustained improvements in VHI-10 exhibited complete or touch glottal closure at 12 months. Two of the seven patients exhibited a small (<1 mm) glottal gap at 12 months. Seven patients experienced initial benefit with later regression 3-4 months after injection.

CONCLUSION

VFIM with silk-HA can offer durable improvement in voice-related outcomes for UVFP past 12 months. A subset of patients treated with silk-HA experienced early loss of effect around 3-4 months postinjection. Clinical factors predictive of sustained treatment response to silk-HA injection require further exploration.

LEVEL OF EVIDENCE

3 Laryngoscope, 134:3679-3685, 2024.

Swallowing improvement surgeries

PURPOSE

To discuss the different swallowing improvement surgeries that address one or more dysfunctional pharyngolaryngeal structures causing dysphagia. These surgeries reduce the risk of aspiration without sacrificing vocal function.

METHODS

We searched the PubMed database and used Google Scholar search engine to find studies discussing the different swallowing improvement surgeries. A manual search of references in selected articles and reviews was done as well. No chronologic limitation was set for the studies; however, only articles written in English and Japanese were considered. Due to the nature of this article, no particular inclusion or exclusion criteria were set when searching for studies to be used as references; however, all relevant studies were reviewed and agreed upon by the authors for inclusion in this review article.

RESULTS/DISCUSSION

Surgeries to improve swallowing function can be categorized into those that reinforce nasopharyngeal closure or pharyngeal contraction, improve laryngeal elevation or pharyngoesophageal segment opening, and those that improve vocal fold closure to protect the airway during swallowing. They are an effective alternative treatment that may significantly improve these patients' quality of life. Swallowing rehabilitation with the altered pharyngolaryngeal structures is required post-operatively to significantly improve patients' dysphagia.

CONCLUSIONS

Surgeries to improve swallowing function address specific dysfunctional sites involved in the swallowing mechanism. Choosing the most appropriate surgery for each patient requires knowledge of the pathophysiology for their dysphagia and detailed pre-operative work-up.

Flexible endoscopic phonosurgery for treatment of functional sequelae after laryngeal oncologic surgery: a narrative review

Flexible endoscopic phonosurgery (FEPS) is one of the most recent and constantly evolving operative techniques in the field of minimally invasive laryngeal surgery. Thanks in part to the possibility of using new technologies, such as digital endoscopes, laser fibres, and different laryngeal injection materials, its fields of application have rapidly expanded. This narrative review describes the current possible indications of FEPS ranging from injection laryngoplasties in cases of vocal cord paralysis or mass defect, to the correction of dysphagia after open partial horizontal laryngectomies. Use of microscissors, microforceps, and laser fibres also allows this technique to be applied for removal of superficial vocal cord lesions, avoiding general anaesthesia in an increasing number of patients.

Silk-Hyaluronic Acid for Vocal Fold Augmentation: Safety Profile and Long-Term Voice Outcomes

OBJECTIVES

Silk-hyaluronic acid (silk-HA) is a novel vocal fold augmentation material used in humans since July 2020. We aim to describe indications, voice outcomes, and longevity data for silk-HA injectable when used for vocal fold injection (VFI) augmentation in a large cohort of patients with longer-term follow-up than preliminary clinical studies.

METHODS

Retrospective chart review of Silk-HA injections for glottic insufficiency (GI) and follow-up between July 2020 and November 2023. Subject demographics, diagnoses, volume of material injected, VHI-10 data, time from injection, need for reinjection, and complications were collected. Blinded perceptual voice analysis of randomly selected pre- and post-intervention voice samples for unilateral vocal fold paralysis patients was performed by three voice-specialized speech-language pathologists, and changes in VHI-10 determined at various time intervals up to 1year and beyond.

RESULTS

A total of 160 silk-HA injection procedures were performed: 59% female, with a mean age of 66± 13 (range 21-90) years. Ninety-four subjects had unilateral paralysis (58.4%); the remainder had scar, atrophy, paresis, or a combination thereof. Mean volume of silk-HA injected was 0.24± 0.14 cc. Major complications were rare, most notable for laryngoscopic evidence of hemilaryngeal edema (n = 6, 3.8%), with a readmission rate to hospital of 1.3% (n = 2). There was a statistically significant decrease in paired ΔVHI-10 and CAPE-V ratings for each of the postoperative follow-up intervals. A total of 24 (27.2%) repeat medialization procedures were recommended following silk-HA injection for unilateral paralysis.

CONCLUSIONS

This study demonstrates that silk-HA is a safe product for VFI augmentation, and effective injectable for the treatment of GI due to unilateral vocal fold paralysis. Based on the current data, it is reasonable to counsel patients that they should expect benefit for several months following the injection. If patients reach 1year from their injection with a stable and satisfactory outcome, the majority experience ongoing benefit without need for additional procedures, however, the final duration of clinical effect appears to be years, but it is yet to be determined.

Tongue base augmentation to improve swallow function in a cadaveric model

Objectives

To evaluate the feasibility of using Calcium Hydroxylapatite (CaHA) to augment the tongue base for patients with swallowing impairment due to tongue base atrophy.

Methods

A fresh human cadaver was obtained through the institution's body donation program and baseline lateral fluoroscopic images were obtained. A total of 2 mL of CaHA (Prolaryn Plus) were injected into three sites of the base of tongue under flexible endoscopic guidance with a 22G, 1.5-inch needle (Monoject, Cardinal Health). Post-lateral fluoroscopic images were obtained and pharyngeal area (cm2) and tongue base to pharyngeal wall distance (cm) was measured pre- and postinjection using SwallowTail fluoroscopic measurement software (Belldev Medical).

Results

The procedure was easily performed and the CaHA flowed easily into the cadaveric tongue without evidence of extrusion. The pre-procedural pharyngeal area decreased from 24.36 to 23.14 cm after augmentation. The base of tongue to pharyngeal wall distance decreased from 2.21 to 1.32 cm after augmentation.

Conclusion

Tongue base augmentation with CaHA may be a feasible adjuvant therapy for the management of swallowing impairment secondary to tongue base atrophy. Further investigation is necessary to evaluate the clinical safety and efficacy.

Level of Evidence

4.

A Very Rare Complication of Vocal Fold Augmentation With Calcium Hydroxylapatite: Neck Abscess

INTRODUCTION

Vocal fold injection augmentation is performed routinely for the treatment of glottic insufficiency especially due to unilateral vocal fold paralysis. There are numerous materials that are used for injection laryngoplasty, calcium hydroxylapatite being one of them.

CASE REPORT

We present an interesting case of a 64-year-old male patient with metastatic acinic cell carcinoma of the right parotid gland, who underwent right vocal cord injection laryngoplasty with calcium hydroxylapatite for right vocal cord paralysis with glottal insufficiency and developed a neck abscess.

DISCUSSION

This is the first report in the literature of neck abscess following vocal fold injection laryngoplasty using calcium hydroxylapatite. It seems that over injection of the vocal fold gave rise to extravasation of the injected material outside the laryngeal framework which later became a nidus for infection.

CONCLUSIONS

We present the first case in the literature of neck abscess following vocal fold injection laryngoplasty using calcium hydroxylapatite. Clinicians should be aware of this rare but dangerous complication.

Acoustic and videoendoscopic effects of temporary vocal fold augmentation in an office-based setting: a quasi-experimental study

Background

Vocal-fold augmentation is a continuously developing treatment modality for glottic insufficiency. Patients with glottic insufficiency attend the phoniatrics clinics with increasing frequency. Glottic insufficiency may be due to vocal-fold paralysis, paresis, atrophy, sulcus vocalis, scarring, and vocal-fold deficiency after laryngeal surgery. A variety of materials exist for injection augmentation. This follow-up study aimed to assess the short-term as well as long-term outcomes of vocal-fold injection with calcium hydroxyapatite (CaHA) in patients with glottic gap 1–3 mm.

Method

This study included 25 patients with glottic insufficiency who underwent injection augmentation with CaHA. All patients were scheduled for voice evaluation using a comprehensive subjective and objective battery of assessments. Assessments were performed before the procedure and after the procedure at 2 months and at 1 year.

Results

Perceptual voice quality assessed with the GRBAS scale improved and the results were stable after 1 year. Shimmer and HNR improved continuously through the follow-up sessions, while jitter and f0 showed slight improvement after CaHA injection.

Conclusion

Voice improvement after injection of CaHA requires a minimum of 2 months to develop and may last for a long period.

Vocal fold medialization-A 5-year series of single surgeon consecutive medialization with review of literature

INTRODUCTION

ENT UK released guidelines in 2010 detailing the requisite structure for the creation of a laryngeal intervention clinic. The senior author's practice is the only one regionally that offers this service, and our objective was to review this to determine whether vocal cord medialization injections were showing an improvement in quality of voice for patients.

MATERIALS AND METHODS

Patients were reviewed in a specialist voice clinic prior to being offered vocal cord injection under local anaesthetic in a separate dedicated weekly clinic. They would be assessed by the senior author and a dedicated voice specialist speech and language therapist (SALT). This would include a preinjection grade, roughness, breathiness, asthenia, and strain (GRBAS), Voice Handicap Index (VHI)-10, and the measuring of maximum phonation time (MPT) with the aid of Opera Vox Apple iPad application.

RESULTS

Data were available for 186 injections, on patients with a median age of 66 years (interquartile range [IQR]: 51-75), of whom 61% were male. VHI-10 score improved significantly, from a mean of 26.7 to 12.5 (P < .001). A significant improvement in MPT was also observed, from a median of 3.0 to 6.3 (N = 66, P < .001). Improvements in all components of the GRBAS score were also observed (all P < .001), with between 43% and 88% of cases reporting reductions after the procedure. Patients receiving a repeat procedure saw a significantly smaller improvement in VHI-10 than those where it was the primary treatment (mean reduction: 9.8 vs 15.5, P = .018). Analysis of MPT found a significant correlation between the quantity of injection material used and the degree of improvement observed (rho = 0.355, P = .004).

CONCLUSION

Vocal Cord local anaesthetic medialization injection is a swift, safe, and effective short-term method of improving dysphonia.

Voice Restoration after Radiation and Supracricoid Partial Laryngectomy by Injection Augmentation of the Arytenoid

Supracricoid partial laryngectomy (SCPL) is an organ-preserving surgical technique intended to achieve oncologic control of laryngeal cancer while maintaining laryngeal functions. Most patients who undergo SCPL achieve a serviceable voice. However, several factors can affect the function of the neoglottis after SCPL. We report the case of a 53-year-old male referred for near aphonia after undergoing SCPL for recurrent laryngeal carcinoma initially treated with radiation. Calcium hydroxylapatite injection augmentation of the right arytenoid was performed to assist neoglottic closure. Flexible laryngoscopy demonstrated greatly improved neoglottic closure postoperatively, and the patient's voice was successfully restored. This case demonstrates a novel technique for voice restoration in patients who have undergone partial laryngectomy.

Safety of office-based percutaneous injection laryngoplasty with calcium hydroxylapatite

OBJECTIVE

To evaluate the safety of office-based calcium hydroxylapatite (CaHA) injection laryngoplasty via the cricothyroid approach through an analysis of all procedures performed over a period of 10 years at a single institution.

METHODS

In total, 962 office-based CaHA injection laryngoplasty via the cricothyroid approach procedures were performed by a single physician at our institution between 2007 and 2016. From these, 955 procedures performed in 617 patients were included in our analysis. The medical records of all 617 patients were retrospectively reviewed. We classified all procedure-related complications according to the time of onset. Complications that occurred during the procedure were considered intraprocedural complications, whereas complications that developed within 1 week after injection and those that developed after 1 week and were recorded more than twice in the medical records were considered acute and delayed complications, respectively. Failed cases were categorized separately as failure.

RESULTS

Five cases were failed (0.5%). Intraprocedural complications included superficial injection in eight cases (0.8%). Acute and delayed onset of dyspnea was observed in three (0.3%) and two (0.2%) cases, respectively. The incidence of failures and major complications requiring active intervention was 1.6%.

CONCLUSION

Our findings suggest that office-based CaHA injection laryngoplasty via the cricothyroid approach is as safe as conventional transoral injection laryngoplasty.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:2361-2365, 2019.

Speech disorders in Parkinson's disease: pathophysiology, medical management and surgical approaches

The prevalence of speech disorders among individuals with Parkinson's disease (PD) has been reported to be as high as 89%. Speech impairment in PD results from a combination of motor and nonmotor deficits. The production of speech depends upon the coordination of various motor activities: respiration, phonation, articulation, resonance and prosody. A speech disorder is defined as impairment in any of its inter-related components. Despite the high prevalence of speech disorders in PD, only 3–4% receive speech treatment. Treatment modalities include pharmacological intervention, speech therapy, surgery, deep brain stimulation and vocal fold augmentation. Although management of Parkinsonian dysarthria is clinically challenging, speech treatment in PD should be part of a multidisciplinary approach to patient care in this disease.

Decreased intramuscular calcium hydroxyapatite implant resorption in a murine model of osteoporosis

OBJECTIVE

Calcium hydroxyapatite (CaHA) is a common material for vocal fold injection augmentation. Durability is variable, and factors involved in implant longevity are not understood. Animal models of osteoporosis show decreased bone density and increased mineral liberation, suggesting CaHA retention may be altered in these conditions.

STUDY DESIGN

Prospective murine investigation.

METHODS

Fourteen skeletally mature, 10-month-old female Sprague-Dewley rats were treated by one of three interventions: oophorectomy, laparotomy without oophorectomy (sham), or monthly risedronate injection (90 μg/kg, subcutaneous). CaHA was implanted into the right lateral thigh muscle in all animals at the time of procedure or first risedronate injection. After 17 weeks, all rats were sacrificed, and the residual CaHA isolated from excised lateral thigh muscle through incubation in a 900 °C calcinator for 9 hours.

RESULTS

Mean CaHA mass remaining in the oophorectomy group was 65.9 (standard deviation ± 16.1) mg, compared to 44.4 ± 10.0 mg CaHA in the risedronate group and 48.6 ± 7.5 mg in the sham group. One-way analysis of variance found a statistically significant difference between the oophorectomy and risedronate groups but not between the sham and other groups, F(2,11) = 4.404, P = 0.039.

CONCLUSION

Persistent estrogen deficiency in a murine model of osteoporosis demonstrated decreased rate of CaHA resorption. This suggests that hormone alterations associated with osteoporosis may alter the longevity of CaHA implant resorption through an uncertain mechanism.

LEVEL OF EVIDENCE

NA. Laryngoscope, 2576-2580, 2018.

Bilateral Vocal Fold Medialization: A Treatment for Abductor Spasmodic Dysphonia

INTRODUCTION

Abductor spasmodic dysphonia, a difficult-to-treat laryngologic condition, is characterized by spasms causing the vocal folds to remain abducted despite efforts to adduct them during phonation. Traditional treatment for abductor spasmodic dysphonia-botulinum toxin injection into the posterior cricoarytenoid muscle-can be both technically challenging and uncomfortable. Due to the difficulty of needle placement, it is often unsuccessful. The purpose of this investigation is to present a previously undescribed treatment for abductor spasmodic dysphonia-bilateral vocal fold medialization.

METHODS

A retrospective case review of all cases of abductor spasmodic dysphonia treated in a tertiary care laryngology practice with bilateral vocal fold medialization over a 10-year period was performed. The Voice Handicap Index and the Voice-Related Quality of Life surveys were utilized to assess patient satisfaction with voice outcome.

RESULTS

Six patients with abductor spasmodic dysphonia treated with bilateral vocal fold medialization were identified. Disease severity ranged from mild to severe. All six patients reported statistically significant improvement in nearly all Voice Handicap Index and Voice-Related Quality of Life parameters. They reported fewer voice breaks and greater ease of communication. Results were noted immediately and symptoms continue to be well controlled for many years following medialization.

CONCLUSIONS

Bilateral vocal fold medialization is a safe and effective treatment for abductor spasmodic dysphonia. It is performed under local anesthesia and provides phonation improvement in the short and long term.

Injection laryngoplasty as miniinvasive office-based surgery in patients with unilateral vocal fold paralysis - voice quality outcomes

Introduction

Injection laryngoplasty (glottis augmentation) is the preferred method in surgical management of unilateral vocal fold paralysis (UVFP). Traditionally, these procedures are performed in the operating room. Nowadays, however, these procedures have moved into the office.

Aim

To evaluate the voice quality after transoral injection laryngoplasty under local anaesthesia in patients with unilateral vocal fold paralysis.

Material and methods

Fourteen subjects (5 women and 9 men) with unilateral vocal fold paresis (9 with right vocal fold paresis and 5 with left vocal fold paresis) were included in the study. The mean age of the group was 57.8 ±19.0 years (32–83 years). All of the injection laryngoplasties were performed transorally, under local anaesthesia. The injection material was calcium hydroxylapatite. Before and 1, 3 and 6 months after the procedure the following variables were evaluated: voice perception, videostroboscopy, acoustic analysis, aerodynamic evaluation, and the subjective rating of the voice quality by the patient.

Results

After injection laryngoplasty, complete glottal closure was achieved or there was a significant improvement in the glottal closure of each subject. We noted great improvement in the post-injection objective and subjective voice outcomes and patients reported improvement in the voice-related quality of life.

Conclusions

The transoral approach for injection laryngoplasty under local anaesthesia is an effective and safe way to treat incomplete glottal closure in patients with UVFP. The transoral approach is an efficient alternative to other surgical techniques used for vocal fold injection.

Medialization Laryngoplasty After Injection Augmentation

OBJECTIVES

This study aims to assess the effect of vocal fold injection augmentation (IA) on subsequent medialization laryngoplasty (ML).

STUDY DESIGN

A retrospective cohort study with follow-up telephone survey was carried out.

METHODS

Clinical records of patients with unilateral vocal fold paralysis or paresis (VFP) who underwent ML between April 2006 and March 2015 were reviewed. Patients who underwent IA before ML were compared with patients who did not, with respect to demographic information, symptoms, Voice Handicap Index-10 (VHI-10), etiology of VFP, and revision rate. Among patients undergoing IA, the effects of injection material and of interval from IA to ML on revision rate were assessed. Follow-up telephone surveys were conducted to evaluate long-term outcomes using VHI-10 and a condition-specific questionnaire.

RESULTS

One hundred thirty-five patients (70 male:65 female) with vocal fold paralysis (125) or paresis (10) underwent ML (96 left:39 right). Sixty-six (48.9%) patients underwent concurrent arytenoid adduction. Fourteen (10.4%) patients required revision. Fifty-six (41.5%) patients had prior IA; five (8.9%) patients underwent revision. Seventy-nine (58.5%) patients did not have IA; nine (11.4%) patients required revision (P = 0.78). Neither augmentation material nor length of interval between last IA and ML affected the revision rate (P = 1.00; P ≥ 0.11 for all tested intervals, respectively). No difference in follow-up VHI-10 score was found between patients who had IA before ML and patients who had not (P = 0.73).

CONCLUSIONS

IA does not appear to affect the revision rate or long-term outcome of subsequent ML.

Effectiveness of Calcium Hydroxylapatite Paste in Vocal Rehabilitation

Objectives

We determined the effectiveness of calcium hydroxylapatite (CaHA) paste in vocal rehabilitation.

Methods

We examined a retrospective case series of 39 adult patients who underwent CaHA paste injection for vocal fold rehabilitation over a 5-year period. The outcomes included the change in the Voice Handicap Index (VHI) score; procedure-related complications; and the need for follow-up voice procedures.

Results

The VHI scores demonstrated overall improvement, with a decrease from the preoperative mean of 61.2 ± 24.0 to a postoperative mean of 35.9 ± 26.3 (p = 0.0001) after a mean follow-up time of 17.8 ± 13.6 months. The procedure was more likely to succeed in patients with paralysis and/or paresis than in patients with glottic soft tissue defects. After injection, the VHI scores worsened in 3 of 7 patients (43%) in the soft tissue defect group, compared to only 2 of 28 (7%) in the paralysis and/or paresis group (p = 0.04). Four of 7 patients with soft tissue defects (57%) required secondary vocal procedures to improve the voice, compared to only 2 of 32 (6%) in the paralysis and/or paresis group (p = 0.006).

Conclusions

Injection of CaHA paste results in significantly improved vocal scores in the majority of patients. Use of the paste was less satisfactory in patients with soft tissue defects because of poor retention of the paste in the scarred vocal fold remnant.

The use of injectable calcium hydroxylapatite in the surgically pretreated larynx with glottal insufficiency

OBJECTIVES/HYPOTHESIS

To evaluate the efficacy of vocal fold (VF) augmentation with calcium hydroxylapatite (CaHA) microspheres in the surgically pretreated larynx with glottal insufficiency.

STUDY DESIGN

Prospective clinical pilot study.

METHODS

After several prior reconstructive attempts (following tumor resection, VF paralysis, in sulcus vocalis, and VF scarring), CaHA was injected under general anaesthesia using a transoral microlaryngoscopic approach in 10 patients with residual glottal insufficiency ≤1.5 mm. The postinterventional result was assessed after 1 day, and 1 and 3 months. Evaluation of augmentation comprised intraoperative video/photo documentation, pre-/postoperative videolaryngostroboscopy, as well as established subjective and objective voice function diagnostics (Grade, Roughness, Breathiness [GRB] Scale; Voice Handicap Index; voice range profile; and acoustic-aerodynamic analysis).

RESULTS

In the pretreated VF with no or minimal lamina propria remaining, the exact placement of CaHA was not possible due to unpredictable propagation into the scarred tissue. The results showed an insufficient postoperative augmentation. Accordingly, the voice function did not improve. However, a significant increase of the vocal range from 6.2 ± 3.2 to 8.7 ± 3.9 semitones was observed in the speaking voice profile (P =.02). All other acoustic and aerodynamic parameters remained on the whole unchanged; the slight differences between pre- and postoperative findings were not significant.

CONCLUSIONS

The application of CaHA in the surgically pretreated scarred larynx is not reliable to achieve a sufficient glottal closure and a satisfactory improvement of voice. Though CaHA is a welcome addition to our armamentarium against glottal insufficiency, the suitability for augmentation of scar tissue in the larynx must be considered carefully in each individual case.

LEVEL OF EVIDENCE

4 Laryngoscope, 127:1125-1130, 2017.

Polydimethylsiloxane Particles for Permanent Injection Laryngoplasty

Objectives:

Polydimethylsiloxane (PDMS) particles are a nonresorbable material that allows for permanent vocal fold augmentation. This study investigated morbidity and voice quality in patients treated for unilateral vocal fold paralysis by injection of PDMS particles.

Methods:

Fourteen patients who had neurogenic unilateral vocal fold paralysis of different causes were included in this prospective study. Each patient underwent videostroboscopic assessment before and after operation. Friedrich's dysphonia index (DI), a score system combining subjective and objective parameters, was used to describe voice quality. A DI of 0 reflects a normal voice, and a DI of 3 stands for complete aphonia. The PDMS particles were injected into the paraglottic space by microlaryngoscopy under general anesthesia.

Results:

The median follow-up was 4.1 months. There was no complication attributable to the injection of PDMS particles. The mean DI was 2.8 before operation. After the operation, voice quality improved significantly in each patient, as reflected by a mean postinjection DI of 1.4.

Conclusions:

Particles of PDMS provide a relatively safe and minimally invasive option for permanent vocal fold augmentation. The functional results in terms of voice improvement are comparable to those obtained with other techniques, including thyroplasty. In the European Community, PDMS particles are officially approved for use in the human larynx.

Vocal fold augmentation with calcium hydroxylapatite (CaHA)

Objectives

Evaluate the effectiveness of CaHA injection for patients with glottal incompetence.

Methods

Multi-center, open-label, prospective clinical study with each patient serving as his/her own control. Voice-related outcome measures were collected for pre-injection and 1, 3, and 6 months.

Results

Sixty-eight patients were available for evaluation. Fifty percent of the injection procedures were done in office. Fifty-seven percent were diagnosed with unilateral paralysis and 42% with glottal incompetence with mobile vocal folds. Patient satisfaction 6 months post showed 56% had significantly improved voice and 38% reported moderately improved voice. Paired t tests from baseline to 6 months showed significant improvements on the VHI and VAS (vocal effort), CAPE-V judgments of voice severity and videoendostroboscopy ratings of glottal closure, and objective voice measures of glottal closure (MPT and S:Z ratio).

Conclusions

Preliminary results in this large cohort of patients demonstrate excellent clinical results.

Autologous grafts for treatment of vocal sulcus and atrophy

Objectives

To obtain complete glottal closure, and evaluate improvement of vocal fold vibration amplitude and vocal quality in patients with sulcus vocalis.

Methods

Autogenous fat and/or fascia augmentation was used in 34 patients with sulcus vocalis. Mean follow-up time was 1 year. The perceptual acoustic and phonatory functions and videolaryngostroboscopic data were evaluated before and after the procedure.

Results

Most of the individuals reported an improvement of vocal quality, a complete glottal closure, an enhancement of mucosal wave excursion, and significant results of acoustic perceptual and phonatory functions after the surgery.

Conclusion

Fat and fascia injections are effective autogenous implants and should be considered options in the treatment of patients with sulcus vocalis and vocal fold atrophy.

Injectable treatments for female stress urinary incontinence

The use of injectable agents for the treatment of stress urinary incontinence (SUI) is an option for female patients who are unwilling to undergo surgery, or have concurrent conditions or diseases that render surgical treatment unsuitable. To be effective for SUI, an injectable agent must be nonimmunogenic, hypoallergenic, biocompatible, permanent, nonerosive, nonmigratory and painless. It must also heal with minimal fibrosis, possess a long-term bulking effect, and be easily stored and handled. Glutaraldehyde cross-linked bovine collagen (Contigen), silicone polymers (Macroplastique), Durasphere, calcium hydroxyapatite (Coaptite), polyacrylamide hydrogel (Aquamid, Bulkamid), Permacol, and stem cell therapy have been used as injectable agents. Patients must be informed that treatment with injectable agents is not as effective as surgical treatment, and that such agents might necessitate additional and repeated administrations in order to achieve the desired therapeutic effect.

Serial computed tomographic and positron emission tomographic properties of injection material used for vocal fold augmentation

OBJECTIVES/HYPOTHESIS

This study aimed to demonstrate the radiological properties of hyaluronic acid (HA) and calcium hydroxylapatite (CAHA) on serial computed tomography (CT) and positron emission tomography (PET) scan.

STUDY DESIGN

Retrospective Case Series.

METHOD

Retrospective chart and imaging analysis of patients who underwent HA or CAHA injection laryngoplasty.

RESULT

Total of 243 patients who underwent more than one CT of PET after last injection laryngoplasty were included. Sixty-eight patients received HA injection and 175 patients received CAHA injection. In all cases HA showed hypo-density in CT and no abnormal uptake on PET. CAHA showed bright calcific density on CT scan and high uptake on PET but had disappeared with time in 18 months if injected less than 0.85 mL in amount.

CONCLUSION

These findings support previous clinical studies on CAHA longevity and provide proper radiological interpretation on injection materials in the vocal folds.

LEVEL OF EVIDENCE

IV (Case series).

Comparative analysis on the efficiency of the injection laryngoplasty technique using calcium hydroxyapatite (CaHA): the thyrohyoid approach versus the cricothyroid approach

OBJECTIVES

Temporary or permanent vocal paralysis can occur after head and neck surgery for thyroid cancer, esophageal resection, a chest operation that includes lung parenchymal resection due to a vagus or recurrent laryngeal nerve injury, and so forth. These days, the main treatment for vocal fold paralysis is the injection laryngoplasty through the cricothyroid (CT) approach. However, the CT approach is difficult in that an operator cannot see from the tip of the needle to the vocal fold. The aim of this study was to determine the efficacy of the thyrohyoid (TH) approach compared with the CT approach using calcium hydroxyapatite (CaHA) in patients with permanent unilateral vocal fold palsy.

METHODS

From March 2008 to July 2012, 68 consecutive injection laryngoplasties were performed in patients with unilateral glottic insufficiency. Percutaneous injection was performed under local anesthesia into the vocalis muscle, using disposable 25 gauge, 11cm long spinal needles through the CT membrane or TH membrane. Of the 68 patients, videostroboscopic findings and acoustic, perceptual, and subjective evaluations were completed for 64 patients before injection and at 3 months after injection.

RESULTS

In the 64 patients, the CT and TH approaches were used in 30 and 34 patients, respectively. The videostroboscopic findings, acoustic and perceptual parameters (maximum phonation time, jitter, shimmer, and noise-to-harmonic ratio), and Voice Handicap Index significantly improved after the injection in both the CT and TH groups (P<0.05).

CONCLUSION

Based on the results of this trial, injection laryngoplasty using the TH approach is an effective alternative to the CT approach, especially for the injection of CaHA in patients with permanent unilateral vocal fold palsy.

Complications of injection laryngoplasty using calcium hydroxylapatite

OBJECTIVE

To report the adverse effects of using calcium hydroxylapatite (CaHA) paste as a vocal fold filler.

METHODS

Approval of this study was obtained through the institutional review board at Drexel University College of Medicine. Sixteen patients had 22 vocal fold injections with CaHA paste to treat glottic insufficiency. The initial procedures were performed at three different institutions between January 2006 and August 2009. Diagnosis and treatment of the complications in all cases were performed at our institution. Pre- and postinjection mucosal waves were assessed using strobovideolaryngoscopy when possible. All stroboscopic examinations were reviewed independently. Decreases in amplitude and waveform were classified as mild, moderate, or severe. Implant location was examined using computed tomography (CT) scan with 1-mm cuts through the larynx in patients suspected of having implant malposition. Vocal fold function was compared before and after injection, as well as after implant removal in selected cases. Histological section of explanted material was obtained. Major and minor complications were noted in 19 vocal folds.

RESULTS

Ten major complications were encountered after surgery at three institutions. These included four vocal folds with adynamic mucosa, six with a severely decreased wave, and two granulomas affecting the vibratory margin. CT scanning confirmed six cases of implant malposition (possibly migration). Six implants were removed through endoscopic lateral cordotomy between 2 and 24 months after injection. Mucosal wave function recovered in five vocal folds after explantation. Minor complications were encountered in nine additional vocal folds. These included tissue inflammation marked by edema, erythema, and mild-to-moderate mucosal wave restriction and hypervascularity.

CONCLUSION

Injection laryngoplasty using CaHA paste has been regarded as an effective treatment for glottic insufficiency. In some patients, CaHA can cause an intense inflammatory reaction, potentially migrate, and compromise vocal fold function. It should be used with full understanding of the potential serious adverse reactions and risk of at least minor impairment of vibratory function.

Implantation of an atelocollagen sponge with autologous bone marrow-derived mesenchymal stromal cells for treatment of vocal fold scarring in a canine model

OBJECTIVES

Vocal fold scarring remains a therapeutic challenge. A new regenerative approach is needed to restore disorganized extracellular matrix. Tissue regeneration requires appropriate cells and a scaffold. Bone marrow-derived mesenchymal stromal cells (BMSCs) are multipotent and secrete many kinds of growth factors to regenerate tissues. Atelocollagen sponges have many large pores that permit cell entry. The present study was performed to evaluate whether implantation of an atelocollagen sponge plus BMSCs is effective for the treatment of vocal fold scarring.

METHODS

Twelve beagles underwent implantation of an atelocollagen sponge or of an atelocollagen sponge with autologous BMSCs (1.0 x 10(6) cells) in the subepithelial pockets of scarred vocal folds. Six months after the operation, vibratory examinations and histologic examinations were performed.

RESULTS

Mucosal vibrations improved significantly for the atelocollagen sponge-implanted vocal folds. Histologic analyses revealed favorable restoration of the extracellular matrix in the lamina propria. Increased distribution of hyaluronic acid and decreased dense collagen deposition were also noted. These improvements were enhanced by implantation of BMSCs.

CONCLUSIONS

Implantation of atelocollagen sponges with autologous BMSCs into scarred vocal folds significantly increased hyaluronic acid distribution and decreased dense collagen deposition in the lamina propria, leading to better mucosal vibration.

Chondrocytes suspended in modified fibrin glue for vocal fold augmentation: An in vitro study in a porcine larynx model

BACKGROUND

Injection laryngoplasty is an option for treatment of dysphonia following vocal fold paralysis. Modified fibrin glue with suspended chondrocytes might be a favorable cell-based material for permanent vocal fold medialization.

METHODS

We compared fibrin glue with suspended chondrocytes to collagen and hyaluronic acid gels concerning alteration of vocal fold vibration and correct intralaryngeal placement after intralaryngeal injection into porcine larynges. Viscoelastic properties of the materials were analyzed by means of a parallel plate rheometer.

RESULTS

Fibrin glue with cells was comparable to collagen and hyaluronic acid with respect to amplitudes, symmetry, and periodicity of vocal fold vibration. Application and positioning of fibrin glue with suspended chondrocytes were technically undemanding and comparable with controls. Complex stress modulus of fibrin glue with suspended cells was comparable to that of collagen gel.

CONCLUSIONS

Fibrin glue with suspended chondrocytes seems suitable for the indication of injection laryngoplasty and holds promise for permanent vocal fold medialization.

Correlação entre o envelhecimento e as dimensões das pregas vocais

OBJETIVO: avaliar as dimensões das pregas vocais em ambos os sexos e correlacioná-las com o envelhecimento. MÉTODO: foram estudados 30 cadáveres (15 mulheres e 15 homens) na faixa etária de 60 a 102 anos. Para isto foram seguidas quatro etapas sequenciais: 1ª) História clínica do cadáver; 2ª) Remoção da laringe; 3ª) Dissecação da laringe; 4ª) Morfometria das dimensões das pregas vocais. Trata-se de um estudo experimental. RESULTADOS: o comprimento da prega vocal masculina com média de 15,90 mm foi maior que o da feminina com 10,39 mm. A largura da prega vocal masculina foi maior com média de 2,37 mm que a feminina com 2,31 mm. A média geral da espessura também foi maior no sexo masculino com média de 2,55 mm em comparação com a feminina com 2,38 mm. Não foram encontradas diferenças estatísticas entre a idade e o comprimento, largura e espessura das pregas vocais em ambos os sexos. CONCLUSÃO: as dimensões de comprimento, largura e espessura das pregas vocais foram maiores no sexo masculino. Entretanto, não houve diferença, estatisticamente significante, entre as três dimensões das pregas vocais durante o envelhecimento em ambos os sexos.

Vocal fold injection: review of indications, techniques, and materials for augmentation

Vocal fold injection is a procedure that has over a 100 year history but was rarely done as short as 20 years ago. A renaissance has occurred with respect to vocal fold injection due to new technologies (visualization and materials) and new injection approaches. Awake, un-sedated vocal fold injection offers many distinct advantages for the treatment of glottal insufficiency (vocal fold paralysis, vocal fold paresis, vocal fold atrophy and vocal fold scar). A review of materials available and different vocal fold injection approaches is performed. A comparison of vocal fold injection to laryngeal framework surgery is also undertaken. With proper patient and material selection, vocal fold injection now plays a major role in the treatment of many patients with dysphonia.

Tubeless anaesthesia with sevoflurane and propofol in adult laryngeal surgery

The presence of endotracheal intubation tube or jet ventilation cannula can compromise free view and access to operation area in certain endolaryngeal operations. The objective of this prospective study was to test whether adequate level of anaesthesia could be obtained in adults using tubeless sevoflurane inhalation anaesthesia with spontaneous breathing. In 23 ASA 1-2 patients, 31 treatments were included in the study of which 19 were laser-assisted papilloma or other tumour resections and 12 were fascia injection laryngoplasties. Anaesthesia was induced with propofol and maintained by insufflating sevoflurane mixture to the patient's oropharynx. The adequacy of the anaesthesia level was assessed by monitoring bispectral index, haemodynamic parameters and peripheral oxygen saturation during the anaesthesia. The ENT surgeon estimated operating conditions, whilst the two participating anaesthesiologists assessed the quality of anaesthesia using a 100 mm VAS scale. Sevoflurane contamination in the operating theatre was measured during five treatments. Mean bispectral index was below 40 throughout the operation. Haemodynamic parameters showed only minor changes during the anaesthesia. Both attending anaesthesiologists and operating ENT surgeon were satisfied with the quality of the anaesthesia and operating conditions (VAS 83 ± 15, mean ± SD, range 42-100, and VAS 93 ± 10, range 55-100, respectively). Sevoflurane room air contamination was high in most measured cases. The modification of tubeless inhalation anaesthesia used in this study produced adequate level of anaesthesia with stable haemodynamics and good operating conditions. Sevoflurane contamination can be reduced with more efficient scavenging systems.

Office-based injection laryngoplasty in the irradiated larynx

OBJECTIVES/HYPOTHESIS

To review the clinical results of office-based injection laryngoplasty with two different therapeutic materials in patients with vocal fold paralysis and history of radiation therapy to the larynx.

STUDY DESIGN

Retrospective study.

METHODS

Chart review of 11 patients who underwent office-based injection laryngoplasty with calcium hydroxylapatite or micronized Alloderm. All patients had a history of radiation therapy to the neck, with the larynx included in the radiation field. Voice analyses, clinical outcomes, and complications were reviewed. Efficacy of the procedure was evaluated by comparing pre- and postinjection mean phonation time (MPT) results from voice analysis data.

RESULTS

A total of 15 injections were performed in 11 patients with vocal fold paralysis (one females, 10 males, mean age 62 years). Data from voice analyses before and after the procedure were available for nine injections. The MPT was significantly increased among patients undergoing the procedure (P < .05). All procedures were successful, and only one self-limited complication was reported.

CONCLUSIONS

Office-based injection laryngoplasty is a safe procedure with acceptable clinical results in patients with vocal fold paralysis who have a history of radiation therapy to the larynx.

Injection laryngoplasty with calcium phosphate cement

Objective: To assess the feasibility of injection laryngoplasty with calcium phosphate cement (CPC), which is an injectable paste, self-hardening, and which recrystallizes to calcium hydroxylapatite after injection.

Study Design: A case series with planned data collection.

Methods: Fifty-six patients with unilateral vocal fold paralysis, who received injection laryngoplasty with CPC between August 2003 and August 2007 with a minimum follow-up period of six months, were enrolled in this study. Volumetric and migration analysis for injected CPC were performed using CT after surgery. Vocal function was also assessed by GRBAS subjective voice assessment scale and maximum phonation time (MPT), acoustic analysis including period perturbation quotient (PPQ), amplitude perturbation period (APQ), and noise-to-harmonics ratio (NHR).

Results: No remarkable migration or absorption of injected CPC was observed on CT up to two years after surgery. The average remaining volume of CPC was 87.8% ± 5.3% two years after injection compared to immediately after injection. Significant improvements in GRBAS scales, MPT, PPQ, APQ, and NHR were observed postoperatively. No adverse effects were observed.

Conclusions: Our clinical experience revealed that CPC was safe, nonabsorbable, and effective. Injection laryngoplasty with CPC may be a useful option in the treatment of glottic insufficiency.

Therapy of unilateral vocal fold paralysis with polydimethylsiloxane injection laryngoplasty: our experience

The objective of this study was to document functional results and to compare objective and subjective voice measures after endoscopic laryngoplasty with injection of polydimethylsiloxane (PDMS) for the treatment of unilateral vocal fold paralysis, and to verify PDMS biocompatibility in vocal fold. The design used was a longitudinal prospective study. Fifteen patients with unilateral vocal fold paralysis underwent endoscopic injection of PDMS in general anesthesia. Accurate voice evaluation protocol (acoustic and aerodynamics analyses, GIRBAS [Grade, Instability, Roughness, Breathiness, Asthenia, and Strain] scale, videostrobolaryngoscopy, and Voice Handicap Index test) before, after surgery, and at follow-up time was performed. The median follow-up was 21.7 months (range, 6-35). Data obtained were statistically significant. All acoustic, aerodynamics, perceptive, and subjective evaluations showed a significant improvement. No complications due to PDMS were reported. Functional results were found comparable to framework surgery. Endoscopic injection laryngoplasty with PDMS is a safe and long-term option for treatment of unilateral vocal fold paralysis.