Autologous fat injection into the vocal folds: technical considerations and long-term follow-up

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.

An Unusual Cause of Laryngeal Dyspnea

INTRODUCTION

Medialization laryngoplasty with autologous fat (MLA) is indicated in some patients with glottic insufficiency. The approach is usually safe but long-term complications are poorly described.

CASE REPORT

We present the history of a patient who developed progressive dyspnea and dysphonia two decades after bilateral MLA, which were due to the development of laryngea lipoma into the site of fat injection.

DISCUSSION

The potential relationship between MLA and the development of laryngeal lipoma was discussed. The lipoma may be a long-term survival of too much fat tissue, which was reorganized into a well-limited lipoma over the long-term. Another hypothesis consisted of the injection of fat tissue, including fatty stem cells, and the development of a lipoma over the year through the neovascularization process.

CONCLUSION

We reported the first case of lipoma developed into the laryngeal site of fat injection. Future studies are needed to explore the long-term evolution of injected fat tissue in the context of MLA.

Vocal Fold Fat injection for Glottic Insufficiency: Systematic Review

Vocal fold fat injection is a technique for treating glottic insufficiency (GI) resulting from various conditions. The use of fat as a graft has several advantages over other grafts. Similar pliability, and vibratory characteristics as a normal vocal fold, not causing foreign body reactions, having the potential to contain stem cells, and often can be done in the office. Long-term results, however, are unpredictable. The objective of this study is to carry out a systematic review of published articles using the technique of fat injection in the vocal folds.

STUDY DESIGN

Systematic review.

REVIEW METHODS

A literature search was conducted utilizing the combination of the following keywords "vocal folds fat injection," "laryngoplasty," and "autologous fat injection vocal folds." The criteria inclusion of the study for the systematic review were based on PICOTS (population, intervention, comparison outcome, timing, and setting) and Preferred Reporting Items for Systematic Reviews and Meta-analyses statements. Outcomes reviewed included technique, study duration, perceptual and acoustic analysis, and quality of life preoperation and 1-year postoperation.

RESULTS

A systematic review on PubMed, Cochrane, and Embase databases included 13 studies analyzing the data of 472 patients, that had fat injection laryngoplasty for treatment of GI. The causes of GI varied substantially across studies. Considerable heterogeneity across studies was found, including technique for harvest, processing the fat, site of injection, and acoustic analysis. In the studies that measured maximum phonation time (MPT) there was a significant improvement in a follow-up of at least 1 year after the injection. The patient's perception of vocal quality, measured by the Voice Handicap Index, also showed significant improvement in several studies after fat injection laryngoplasty.

CONCLUSION

Fat injection laryngoplasty seems to be safe and effective for GI for at least 12 months. Multiple studies show favorable outcomes, but the lack of control groups, the heterogeneity in inclusion criteria, nonstandardized techniques, and objective voice evaluations limit this evaluation.

Salvage Treatments for Poor Voice Outcomes Following Autologous Fat Injection Laryngoplasty

OBJECTIVE

Fat injection laryngoplasty (FIL) is a common procedure used to correct glottic insufficiency. Nevertheless, few studies have discussed potential treatments for cases with poor voice recovery after FIL.

METHODS

Eighteen patients with unfavorable vocal outcomes from FIL were analyzed. Each of these patients presented persistent dysphonia for more than 2 months following FIL, together with bulging vocal folds and poor mucosal wave. We applied microsurgery as the standard treatment to remove excessive fat. Vocal fold steroid injection (VFSI) was administered to patients that were hesitant or declined to undergo microsurgery. Voice outcomes were evaluated using the Voice Handicap Index-10 (VHI-10), grade-roughness-breathiness (GRB) scores, and smoothed cepstral peak prominence (CPPs).

RESULTS

Six patients underwent microsurgery directly, 6 patients received only VFSIs as a salvage treatment, and the remaining 6 patients received 1 to 3 courses of VFSIs before the decision to undergo microsurgery. Pathology reports were available for 10 patients, and contained 5 instances of adipose tissues, 3 of fat necrosis, 1 of chronic inflammation, and 1 of fibrosis. Seventeen patients reported satisfactory or improved outcomes. We found remarkable improvements in VHI-10, GRB, and CPPs (all P < .05) after salvage treatments for FIL. Subgroup analyses showed comparable voice outcomes for patients undergoing direct microsurgery, VFSI alone, and VFSI followed by microsurgery (P > .05).

CONCLUSIONS

This study demonstrated that fat overinjection and/or fibrotic change in the injected vocal folds may cause poor voice outcomes after FIL. Both microsurgery and VFSI could be applied as salvage treatments with good voice recovery profiles.

LEVEL OF EVIDENCE

Level 4.

Treatment Options and Voice Outcomes for Patients With Unilateral Vocal Fold Paralysis After Thyroidectomy

Objectives

This study investigated the treatment options and clinical outcomes of voice therapy (VT), hyaluronic acid (HA) injection, autologous fat injection (FI), and medialization thyroplasty (MT) in patients with unilateral vocal fold paralysis (UVFP) after thyroidectomy.

Study Design

Retrospective case series.

Setting

A tertiary teaching hospital.

Methods

This study included 51 patients with post-thyroidectomy UVFP who underwent VT (n = 20), HA injection (n = 14), FI (n = 12), or MT (n = 5) from January 2016 to June 2021. The treatment outcomes were evaluated using 10-item voice handicap index (VHI-10), maximal phonation time (MPT), and auditory perceptual rating using GRB scales (i.e., grade, roughness, and breathiness) before and 3 to 6 months after treatment.

Results

Patients received HA injection presented a significantly shorter interval after thyroidectomy (mean: 4.6 months), followed by VT (6.7 months), FI (12.3 months), and MT (22.4 months). The results exhibited improvement in most of the outcomes after all of the four treatments. Additional comparisons indicated that VHI-10 scores improved the most among patients receiving MT, followed by HA, FI, and VT. The differences of MPT and GRB scores among the 4 treatment groups were non-significant.

Conclusions

The results revealed that VT, HA, FI, and MT can all improve the voice outcomes of patients with post-thyroidectomy UVFP. The optimal treatment approach should be individualized according to the patient's preference and vocal demand, and the interval between thyroidectomy and intervention.

Clinical study of injectable collagen scaffold with autologous fat cells for repair of severe vocal fold injury

Cell retention and survival after transplantation remains a major problem for long-term efficiency in therapy of severe vocal fold injury with autologous cells. In this study, injectable collagen scaffold was used to deliver autologous fat cells (AFCs) for repairing of severe vocal fold injury. We found injectable collagen scaffold could enhance the retention and survival of green fluorescent protein (GFP) labeled fat cells in the transplantation sites in rats. Based on these data, a randomized controlled clinical trial was conducted to evaluate the safety and efficiency of transplantation of collagen scaffold with AFCs for severe vocal fold injury. Ten patients with vocal fold paralysis were randomly assigned to control (AFCs only) and intervention (AFCs + collagen) groups. AFCs with or without collagen scaffold were injected into vocal folds of patients under general anesthesia, respectively. The safety and efficacy were regularly assessed during 24 months post-surgery. No obvious complications occurred in all patients during the follow-up. The collagen scaffold maintained the stability of implants after injection and reconstructed the vocal fold structure. The improvement of voice quality of patients was observed through voice quality evaluation with the voice handicap index (VHI) questionnaire, as well as acoustic analysis of maximum phonation time, jitter, and shimmer. The VHI score of patients in AFCs + collagen group improved significantly than those in AFCs group at 6, 12 and 24 months post-surgery. It demonstrates the injectable collagen scaffold is safe and efficient for delivering AFCs for vocal fold injury.

Lipoinjection for Unilateral Vocal Fold Paralysis Treatment: A Systematic Review and Meta-Analysis

INTRODUCTION

Lipoinjection is one of the available treatments for unilateral vocal fold paralysis.

OBJECTIVE

To evaluate lipoinjection predictability, and analyze the differences in safety and efficacy of the different techniques.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS AND RESULTS

A systematic review on Medline, Cochrane, and Scopus databases included 49 articles analyzing the data of 1,166 patients, concerning technical details and voice parameters changes. Lipoinjection used a mean volume of 1.3 mL, 95% confidence interval (CI) (0.92, 1.69)-average overcorrection of 30%. Meta-analysis of pre- and postoperative voice parameters' means showed a significant improvement at 6 months of mean phonation time (preoperative: 5.12, 95% CI [4.48, 5.76]-6 months: 10.46, 95% CI [9.18, 11.75]), Jitter (preoperative: 2.71, 95% CI [2.08, 3.33])-6 months: 1.37, 95% CI [1.05, 1.70]), Shimmer (preoperative: 4.55, 95% CI [3.04, 6.07]-6 months: 2.57, 95% CI [1.69, 3.45]), grade (preoperative: 2.15, 95% CI [1.73, 2.57]-6 months: 0.12, 95% CI [0.97, 1.43]), breathiness (preoperative: 2.012, 95% CI [1.48, 2.55]-6 months: 0.99, 95% CI [0.58, 1.40]), and asthenia (preoperative: 1.90, 95% CI [1.33, 2.47]-6 months: 0.75, 95% CI [0.17, 1.33]) of GRBAS (Grade, Roughness, Breathiness, Asthenia and Strain), and Voice Handicap Index-30 (preoperative: 72.06, 95% CI [54.35, 89.76]-6 months: 26.24, 95% CI [19.58, 32.90]). Subgroup analysis by harvesting technique concluded in no statistically significant difference between them. Few complications were reported. Reintervention was only required for 86 patients.

CONCLUSION

Lipoinjection seems a safe therapeutic option for unilateral vocal fold paralysis, with available data showing an efficacy lasting 6 months to 1 year. Laryngoscope, 2021.

Autologous Adipose Tissue Injection of Vocal Cords in Presbyphonia

OBJECTIVE

This series evaluates the long-term results of autologous adipose injection (AAI) in patients older than 65 years with presbyphonia.

STUDY DESIGN

Retrospective cohort study.

SETTING

Academic secondary medical center.

METHODS

This was a retrospective study with a minimum follow-up of 12 months. All patients underwent AAI for atrophy of both vocal folds due to presbyphonia. We measured subjective parameters as Voice Handicap Index-10 (VHI-10) or GRBAS scale (grade, roughness, breathiness, asthenia, strain) and objective measures such as maximum phonation time (MPT) or square pixel closure defect. We reviewed the medical records of patients undergoing AAI during the 2011-2018 period. An analysis of the demographic variables of the group was performed, as well as the values of VHI-10, GRBAS, and MPT, and the minimum closure defect measured in square pixels and the number of closed frames in the glottal cycle before and after the intervention.

RESULTS

At 12 months, 17 of 18 patients reported subjective and VHI-10 improvement. The mean preoperative VHI-10 (26.7) was significantly higher than the postoperative value (14.4), and the GRBAS scale had a preoperative mean of 8.7 and a postoperative mean of 4.3, both with statistical significance. MPT increased from 7.7 to 12.4 seconds (P < .0001). The minimum closure defect measurements obtained in square pixels changed from 305 to 124, achieving complete closure in 3 patients. The closed phase of the glottal cycle change from 14.3% to 38.2% after the AAI.

CONCLUSIONS

AAI improves long-term vocal fold closure, demonstrating utility in patients with presbyphonia.

Autologous Lipoaugmentation Long-Term Clinical Outcomes: A Systematic Review

OBJECTIVES/HYPOTHESIS

Vocal fold (VF) lipoaugmentation can be employed to treat glottal insufficiency although variable data exist on its length of effectiveness. We aimed to review published long-term outcomes following lipoaugmentation across the literature and compile outcome data.

STUDY DESIGN

Systematic review.

METHODS

A systematic search in September 2020 of PubMed, MEDLINE, Cochrane Library, and Web of Science used the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines to identify 128 relevant articles related to VF lipoaugmentation effectiveness duration. Primary search terms included the following: vocal cord, fat, lipo, and atrophy. Forty-eight full-text articles were reviewed and 31 were included in the final analysis. Primary endpoints included the following: duration of effectiveness per patient-reported outcome measures, objective findings, and additional procedures performed. In addition, fat harvest location and processing techniques were recorded.

FINDINGS

Thirty-one studies totaling 764 patients were included in the review. Indications for augmentation were VF paralysis (N = 690) and atrophy (N = 74). Fat was harvested from the abdominal region in 21 studies (529 patients), the thigh/abdomen in 5 studies (91 patients), and buccal/submental region in 2 studies (33 patients). Processing techniques and injectable volume varied. Across included studies, only 11 of 764 patients (1.4%) reported no improvement in voice and/or swallowing. Within the first year, 71 of 608 patients (11.7%) reported a regression toward baseline. Beyond 1 year and up to 8 years, 27 of 214 patients (12.6%) reported regression from initial improvement. Thirty-three patients underwent additional procedures.

CONCLUSION

Although improvements in voice and swallowing after lipoaugmentation taper over time, most patients experienced long-term benefit. Laryngoscope, 2021.

Pre- and post-operative high-speed videolaryngoscopy in unilateral vocal cord paralysis following autologous fat augmentation

PURPOSE

To compare high-speed videolaryngoscopy (HSV) parameters such as open quotient (OQ), amplitude symmetry index (ASI), phase symmetry index (PSI), and frequency symmetry index (FSI), of the unilateral vocal cord paralysis (UVCP) patients pre and post (after 6 months) autologous fat augmentation.

MATERIALS AND METHODS

This retrospective study evaluated all age and gender patients with UVCP that underwent autologous fat augmentation from July 2016 to July 2019. The OQ, ASI, PSI, and FSI were calculated from the HSV recordings by using the montage and fast Fourier transform point analysis. The pre-and post-operative means were compared using a paired student t-test, with a p-value less than 0.05 considered significant.

RESULT

A total of 37 patients, age 41.2 ± 11.3 years (21 to 67 years), 59.4% females and 40.6% males, were included in the study. The average duration of symptom onset was 2.3 ± 0.87 months. The post-operative mean values of OQ, ASI, PSI, and FSI following the fat augmentation were significantly improved compared to the pre-operative mean values with p-values <0.0001, 0.0018, 0.0011, and 0.0006, respectively.

CONCLUSION

There was a significant improvement in the OQ, ASI, PSI, and FSI in UVCP patients after 6 months of autologous fat augmentation, signifying an enhanced vibratory function. The ability of HSV to measure the minute details of vocal cord vibration by providing quantitative measurements has also been highlighted. The need for future prospective research with an increased sample size and longer duration of follow up is recommended.

Vocal Fold Fat Augmentation for Atrophy, Scarring, and Unilateral Paralysis: Long-term Functional Outcomes

OBJECTIVE

There is a debate regarding the durability of fat implants. Our experience and recent publications suggest fat implantation may deliver a long-lasting improvement. This study aims to present the long-term outcomes for vocal fold fat augmentation using strict harvesting, preparing, and implantation protocols.

STUDY DESIGN

A prospective cohort conducted between 2014 and 2020 (recruitment 2014-2017).

SETTING

An academic tertiary referral center.

SUBJECTS AND METHODS

Twenty-two patients with glottic insufficiency were enrolled: 11 had unilateral vocal fold paralysis (UVFP), and 11 had atrophy or scar. Harvested fat was injected unilaterally or bilaterally into multiple sites. Six of these patients also had simultaneous microlaryngoscopic removal of other benign glottic lesions. Outcome measurements included video stroboscopy; Grade, Roughness, Breathiness, Asthenia, Strain (GRBAS) score; Voice Handicap Index (VHI); and acoustic analysis, performed preoperatively, 3, 12, 24, and 36 months after surgery.

RESULTS

Ten augmentations were unilateral and 12 bilateral. Comparing the preoperative and 36-month postoperative periods, the mean VHI score improved from 73.45 (±22.78) to 44.88 (±28.93), P = .001, and the mean GRBAS decreased from 8.64 (±3.89) to 2.82 (±2.3), P = .001; 24 months postoperatively, the mean fundamental frequency decreased from 163.88 Hz (±41.61) to 150.44 Hz (±41.47), P = .012. Stroboscopic analysis revealed statistically significant improvement in mucosal wave propagation, phase closure, and phase symmetry. Best results were achieved in the UVFP subgroup. Computed tomography scans demonstrated long-term viability of the implanted adipose tissue.

CONCLUSION

Fat is an excellent source of autologous graft. With careful patient selection and proper surgical technique, fat is suitable for long-term correction of glottic insufficiency. Fat augmentation should be considered as a long-lasting or even permanent solution, rather than temporary.

Augmentation of Scarred Vocal Folds With Centrifuged and Emulsified Autologous Fat Grafts

Objective

To review the results of a series of patients with glottic insufficiency caused by scarred vocal folds who underwent injection laryngoplasty with centrifuged and emulsified autologous fat.

Study Design

Prospective cohort.

Setting

Single center, tertiary institution.

Subjects and Methods

Examination of the medical records of 21 patients operated on through injection laryngoplasty with fat grafts for the treatment of dysphonia was performed. All patients were operated on between January of 2015 and September of 2019. The voice variables measured were the GRABS (Grade, Roughness, Breathiness, Asthenia, Strain) scale, the Voice Handicap Index–10 (VHI-10), maximum phonation time, jitter, shimmer, and harmonic/noise ratio before surgery and 8 months later.

Results

Twenty-six injection laryngoplasties were performed in 21 patients during the reviewed period. Seventeen were men, and 4 were women. Mean age was 57.2 (range, 18-80) years. Mean (SD) follow-up time was 20.7 (9.3) months. Etiology of dysphonia was scarring after tumor resection in 17 patients and sulcus vocalis in 4. Five patients received an additional injection laryngoplasty. Statistically significant improvements were observed in all the parameters evaluated ( P < .05).

Conclusions

Injection laryngoplasty with fat grafts processed through centrifugation and emulsification is an effective technique for the treatment of dysphonia caused by glottic insufficiency related to scarred vocal folds, with minimal complication rates.

Autologous Fat Augmentation in the Treatment of Unilateral Vocal Fold Paralysis - A 15-year Experience in a Single Institution

Autologous fat vocal fold augmentation is a widespread surgical procedure that aims to repair glottal incompetence in patients with unilateral vocal fold paralysis (UVFP). However, there are some concerns in the literature about the long-term results of this technique. At the ENT Department of the Zagreb University Hospital Centre, this technique has been in use for more than 15 years, and a retrospective medical chart review was conducted from June 2005 to November 2019. Overall, 78 patients with UVFP met the inclusion criteria for enrolment in the study. All patients underwent at least one preoperative and two postoperative voice assessments, one early (within 3 months from surgery) and one late (at least 1 year after surgery). All tested voice outcome parameters (maximum phonation time (MPT), jitter, shimmer, noise-to-harmonic ratio (NHR)) significantly improved after surgery, both early and late postoperatively (p<0.001). The reoperation rate was only 10.3% (8/78), with the majority of patients in our series experiencing long-term benefits from this surgical procedure. According to the results of our study, autologous fat vocal fold augmentation appears to be a highly useful and effective surgical technique with long-lasting results in the majority of patients suffering from UVFP.

Autologous Fat Augmentation in Post Type III Cordectomy Patients

Neocord formation after Type III cordectomy is insufficient for complete glottic closure due to scarring and soft tissue deficit. This study evaluates the role of autologous fat injection (AFI) in phonosurgical management of patients who have previously undergone Type III cordectomy for early glottic cancer. Data was collected from hospital records of patients who underwent AFI after previously undergoing Type III cordectomy. A minimum duration of 6 months post-cordectomy was maintained before fat injection. Trans-oral injection was performed at a single site. Pre-operative voice evaluation was done using VHI, GRBAS scale and MDVP software. Post-operative evaluation was done at 6 weeks. 21 out of 62 post-Type III cordectomy patients chose to undergo fat augmentation and were included in the study. A comparison of pre-operative and 6 months post-operative AFI voice analysis showed a significant improvement in VHI, all parameters of GRBAS scale, and improvement in Jitter, Shimmer, SPI and NHR. There was a decrease in fundamental frequency but this was not statistically significant. AFI is an effective procedure for surgical voice rehabilitation of patients who have undergone Type III cordectomy for early laryngeal cancer.

Mesenchymal stromal cell injection promotes vocal fold scar repair without long-term engraftment

BACKGROUND

Regenerative medicine holds promise for restoring voice in patients with vocal fold scarring. As experimental treatments approach clinical translation, several considerations remain. Our objective was to evaluate efficacy and biocompatibility of four bone marrow mesenchymal stromal cell (BM-MSC) and tunable hyaluronic acid based hydrogel (HyStem-VF) treatments for vocal fold scar using clinically acceptable materials, a preclinical sample size and a dosing comparison.

METHODS

Vocal folds of 84 rabbits were injured and injected with four treatment variations (BM-MSC, HyStem-VF, and BM-MSC in HyStem-VF at two concentrations) 6 weeks later. Efficacy was assessed with rheometry, real-time polymerase chain reaction (RT-PCR) and histology at 2, 4 and 10 weeks following treatment. Lung, liver, kidney, spleen and vocal folds were screened for biocompatibility by a pathologist.

RESULTS AND DISCUSSION

Persistent inflammation was identified in all hydrogel-injected groups. The BM-MSC alone treatment appeared to be the most efficacious and safe, providing an early resolution of viscoelasticity, gene expression consistent with desirable extracellular matrix remodeling (less fibronectin, collagen 1α2, collagen 3, procollagen, transforming growth factor [TGF]β1, alpha smooth muscle actin, interleukin-1β, interleukin-17β and tumor necrosis factor [TNF] than injured controls) and minimal inflammation. Human beta actin expression in BM-MSC-treated vocal folds was minimal after 2 weeks, suggesting that paracrine signaling from the BM-MSCs may have facilitated tissue repair.

Voice Outcomes following a Single Office-Based Steroid Injection for Vocal Fold Scar

OBJECTIVE

Persistent dysphonia from vocal fold scar remains a clinical challenge, with current therapies providing inconsistent outcomes. We evaluated voice outcomes after a single office-based steroid injection.

STUDY DESIGN

Case series with chart review.

SETTING

Academic medical center.

SUBJECTS AND METHODS

This study was based on pre- and postoperative analysis of patient-reported, perceptual, acoustic, aerodynamic, and videostroboscopic parameters. The sample comprised 25 patients undergoing office-based dexamethasone injection into the superficial lamina propria for mild/moderate vocal fold scar. Average follow-up was 13.7 ± 4.4 weeks; patients completed 3.5 ± 2.3 sessions of voice therapy between assessments. Complete data sets were not available for each parameter; sample size is noted with results.

RESULTS

Voice handicap index (n = 24; P < .001) and glottal function index (n = 22; P < .001) decreased after injection. Total GRBAS score (grade, roughness, breathiness, asthenia, strain) decreased (n = 25; P < .001). Fundamental frequency range increased (n = 24; P = .024). Phonation threshold pressure decreased (n = 14; P = .017). Videostroboscopic parameters of vocal fold edge (P = .004), glottic closure (P = .003), and right mucosal wave (P = .016) improved after injection.

CONCLUSIONS

Office-based steroid injection combined with voice therapy for mild/moderate vocal fold scar is associated with improved patient-reported and functional voice measures. These findings provide preliminary support for this approach. Importantly, the procedure is low risk and can be performed in the office, thus offering a simple treatment alternative to patients with a disorder that has traditionally been difficult to manage. Prospective studies evaluating the effects of multiple injections are warranted.

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.

Airway Resistance and Airflow Dynamics after Fat Injection into Vocal Folds

Objectives:

The aim of this prospective study was to verify whether vocal fold fat augmentation (VFFA) modifies upper airway patency. To the best of our knowledge, this is the first study analyzing the impact of VFFA on laryngeal resistance to airflow.

Methods:

Twenty-one consecutive patients 16 to 74 years of age underwent 24 VFFA operations because of glottic incompetence due to laryngeal hemiplegia (13 patients) or vocal fold tissue defects (8 patients). Flow-volume loop spirometry and body plethysmography were performed before and 1 to 6 months after surgery.

Results:

There were no significant differences between preoperative and postoperative pulmonary volumes (FVC and FEV1), expiratory flows (PEF, FEF50), or inspiratory flows (PIF, FIF50), although a slight increase in inspiratory flows meant that FEF50/FIF50 slightly decreased. Specific airway resistance (sRaw) increased after VFFA, but not in a statistically significant manner (p = .078). None of the patients experienced postoperative stridor. One obese woman with laryngeal hemiplegia had postoperative effort dyspnea; her respiratory studies showed a reduction in inspiratory flows and an increase in sRaw, and demonstrated progressive improvement.

Conclusions:

Flow-volume loop spirometry showed that VFFA does not significantly modify respiratory airflows, although a slight increase of inspiratory airflows suggested an improvement in variable extrathoracic obstruction. Body plethysmography proved to be a sensitive procedure that highlighted the subtle increase in upper airway resistance. Hence, VFFA can be considered a relatively safe procedure for achieving vocal fold medialization, and spirometry and plethysmography can be useful for preoperative assessment and postoperative follow-up.

Combination of Fascia Transplantation and Fat Injection into the Vocal Fold for Sulcus Vocalis: Long-Term Results

Fat injection and fascia transplantation alone have been used to treat patients with sulcus vocalis. No information is available on the effectiveness of these two procedures used in concert to treat sulcus vocalis. The objectives of this study were to conduct the two procedures together and report the long-term results. This article assesses, retrospectively, the effectiveness of the combination treatment of fascia transplantation and fat injection (FTFI) in patients with sulcus vocalis (n = 22). Perceptual acoustic, phonatory function, and videolaryngostroboscopic data were evaluated before and after FTFI treatment in 18 patients. The mean follow-up time was 16.6 months. Sixteen patients had excellent results, 3 reported improvement, and 3 indicated no change. Phonatory function improved significantly in terms of phonation time, grade, roughness (p < .05), and breathiness (p < .001). The videolaryngostroboscopic rating showed significant improvement in vocal fold vibration amplitude and excursion of the mucosal wave (p < .05). Type 3 sulcus responded better to this treatment than did type 2 (sulcus vergeture). No postoperative complications were noted. The FTFI technique consists of an autogenous implant and delivers positive results. It may be considered as an option for patients with sulcus vocalis. It has been demonstrated to achieve excellent results in a majority of patients and to deliver a better prognosis than fat injection alone. Although resorption of fat and fascia is associated with FTFI, the FTFI procedure may be repeated multiple times.

Injection Laryngoplasty with Calcium Hydroxylapatite Gel Implant in an in Vivo Canine Model

The ideal injectable agent for vocal fold medialization is biocompatible, durable, sized to prevent phagocytosis and migration, and formulated for easy injection and does not adversely affect the viscoelastic properties of the vocal fold. We tested a cohesive implant of calcium hydroxylapatite (CaHA) particles in a gel carrier in an in vivo canine model of phonation. Six dogs underwent unilateral recurrent laryngeal nerve section and injection laryngoplasty of the paralyzed vocal fold with a CaHA implant. The six follow-up examinations were performed at 1,2, 3, 6, 9, and 12 months, and the larynx and bilateral neck lymphatic system were harvested for histologic analysis. The CaHA implant adequately medialized the vocal fold to regain glottal closure. The mucosal waves remained unaltered from baseline. The implant remained soft in the larynx and did not migrate to the neck lymphatic system. A localized foreign body giant cell reaction was present on histologic evaluation, but not acute or other chronic inflammation. A size analysis revealed no resorption of the CaHA particles. A decrease in medialization was noted at all follow-up intervals related to resorption of the aqueous-based gel carrier. The CaHA implant appears to be relatively safe and suitable for injection laryngoplasty.

Long-term histological outcomes of injected autologous fat into human vocal folds after secondary laryngectomy

OBJECTIVE: To histologically evaluate the long-term outcomes of autologous fat grafts after injection laryngoplasty in the human larynx.

STUDY DESIGN AND SETTING: We injected liposuctioned fat for vocal fold augmentation in patients with vocal fold paralysis. We suctioned autologous fat from the low abdomen with an 18-G disposable needle and a 20-mL disposable syringe under negative pressure. This is different from the conventional liposuction technique and avoids the use of special equipment. In this article, we report the histological evaluation of 2 patients (patient 1: 12 months, patient 2: 41 months) who required total laryngectomy after autologous fat injection into the vocal folds.

RESULTS: Histological examination revealed normal-appearing viable adipocytes with minimal inflammatory response in both patients.

CONCLUSIONS: Our liposuctioned autologous fat injection histologically offered long-term improvement in patients with impaired glottal closure from vocal fold paralysis. (Otolaryngol Head Neck Surg 2005;132:685-688.)

Vocal fold augmentation by autologous fat injection with lipostructure procedure

BACKGROUND: Fat is theoretically the ideal implant for vocal fold augmentation because it is soft, easily available and biocompatible. However, reabsorption is a frequent cause of long-term failure.

OBJECTIVE: We prospectively tested Coleman's “li-postructure” technique used for facial recontouring in the treatment of glottic incompetence.

STUDY DESIGN AND SETTING: Fourteen patients (aged 18–74 years, mean 48) with breathy dysphonia secondary to laryngeal hemiplegia (7) or anatomical defects (7) underwent vocal fold lipoinjection. Fat harvested by liposuction was centrifuged, and the fat cell layer injected into the vocalis muscle. The patients underwent pre- and postoperative videolaryngostroboscopy, maximum phonation time (MPT) measurements, GRBAS perceptual evaluations, and Voice Handicap Index (VHI) self-assessments.

RESULTS: Voice quality improved soon after surgery and remained stable over 3–26 months (mean 10.6), being confirmed by the GRBAS, MPT and VHI evaluations ( P < 0.005). The results were best in the seven patients with paralytic dysphonia.

CONCLUSION: Lipostructure is a valuable technique for voice rehabilitation in glottic incompetence.

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.

Endoscopic Rehabilitation of Vocal Cord Paralysis with a Silicone Elastomer Suspension Implant

OBJECTIVES: Because of the side effects of Teflon, the risk of infection from the use of collagen, autologous fat resorption, and the lack of alternative substances, injection laryngoplasty tends to be replaced by laryngeal framework surgery as the method of choice for the treatment of unilateral vocal cord recurrent paralysis (LP). The aim of this study was to evaluate the results, for morbidity and voice quality, of treating this paralysis by injection of a silicone suspension elastomer implant (SSEI).

STUDY DESIGN: The study was retrospective, and 19 patients were included. Average follow-up was 25 months (range: 8.3-43).

METHODS: Each patient underwent clinical and videostroboscopic assessment, and had an electroglottographic recording. Subjective assessment was obtained by self-evaluation. Results were classified as good, fair, or poor, and were based on 2 objective and 3 subjective criteria. A search was made for biologic signs of autoimmune disorders.

RESULTS: Good, fair, and poor results were respectively 79%, 16%, and 5%. Each set of subjective data showed voice improvement ( P < 0.05). The fundamental frequency range, percentage of irregularity, and aspiration decreased significantly ( P < 0.05). There was only one case of postoperative dyspnea, which resolved after steroid injection. No biologic signs of autoimmune disorders were found.

CONCLUSIONS: The use of SSEI is safe. Injection laryngoplasty is easy to perform and avoids cervical scarring. Its results are comparable to those obtained with other techniques, including laryngeal framework surgery, even if there is no standard criterion for the evaluation of voice quality. SSEI injection can reasonably be proposed as a surgical treatment for permanent unilateral vocal cord LP.

Assessment of Chinese-Version Voice Outcome Survey in Patients with Unilateral Vocal Cord Paralysis

BACKGROUND: To develop a Mandarin Chinese outcome measure for the assessment of quality of life among unilateral vocal cord paralysis (UVCP) patients.

METHODS: Voice Outcome Survey (VOS) was translated into Mandarin Chinese using a parallel model. The Chinese (Taiwan) version of the VOS (CVOS) was administered to 48 patients with symptomatic UVCP in a prospective manner; the CVOS was validated according to established criteria for reliability, validity, and longitudinal sensitivity.

RESULTS: CVOS demonstrates moderate test-retest reliability (r = 0.59, P < 0.001) and internal consistency (Cronbach's α = 0.63). CVOS significantly correlates with most of the subscales in the Mandarin Chinese (Taiwan) version of 36-Item Short-Form Health Survey (SF-36) with only two exceptions (GH, general health; VT, vitality). The standardized response mean for the CVOS total score is 1.91, indicating excellent sensitivity to detect clinical changes.

CONCLUSIONS: Performance characteristics of the CVOS are equivalent to the English-version VOS. CVOS is a valid tool to evaluate adults with UVCP-related problems among Chinese-speaking populations.

Augmentation Autologous Adipose Injections in the Larynx

OBJECTIVE

Autologous adipose injection (AAI) is a recognized method for vocal fold augmentation. The study's purpose is to explore short- and long-term outcomes of AAI.

METHODS

Retrospective chart review of 43 patients undergoing AAI was performed; patient perception of outcome, Voice Handicap Index (VHI), maximum phonatory time (MPT), and disposition were evaluated.

RESULTS

Over 5 years, 43 AAI patients had documented postoperative follow-up (25 paralysis, 8 paresis, 9 bowing/presbylarynges, and 5 scar/sulci). Mean follow-up was 32 weeks. There was gradual patient loss to follow-up. Thirty-nine of 40 (98%) had patient-reported improvement at 6 weeks, 28 of 34 (82%) had improvement at 2 to 6 months, with 10 of 12 (83%) sustaining their improvement for >1 year. Significant improvement in mean VHI was observed at 4 to 6 weeks (mean reduction, 26; P < .0001) and 2 to 6 months (mean reduction, 23; P < .0001). Improvement in mean MPT was observed at 4 to 6 weeks (mean increase, 8 s; P < .0001), 2 to 6 months (6 s; P = .007), and >1 year (4 s; P = .03). Eight patients went on to medialization laryngoplasty.

CONCLUSION

AAI successfully augments vocal folds in short-term outcomes with some gradual decrease in effectiveness. Although patient attrition limited conclusions, objective long-term benefit may occur in >50% of patients.

Autologous fat augmentation of the vocal fold with basic fibroblast growth factor: Computed tomographic assessment of fat tissue survival after augmentation

CONCLUSION

The volume of fat tissue loss after vocal fold augmentation can be decreased when augmentation is performed with addition of basic fibroblast growth factor (b-FGF).

OBJECTIVES

The effectiveness of augmentation is easily decreased due to absorption. Canine experiments have confirmed that the decreased effectiveness caused by absorption after augmentation can be reduced by administering low-concentration b-FGF. Clinical application was trialed after acquiring approval from the institutional clinical review committee.

METHOD

Autologous fat tissue with b-FGF was injected into the vocal folds in cases of unilateral vocal cord paralysis. This study compared fat tissue survival after injection by assessing images from computed tomography (CT).

RESULTS

Assessments using CT revealed that the decrease in volume of injected fat tissue was smaller in cases treated using b-FGF than in cases using the conventional method. No severe complications were encountered using this method.

Management of Dysphonia After Radiation Therapy

Radiation-induced dysphonia can develop after radiation for primary laryngeal cancer or when the larynx is in the radiation field for nonlaryngeal malignancy. The effects are dose dependent and lead to variable degrees of dysphonia in both short- and long-term follow-up. Rehabilitation of the irradiated larynx can prove frustrating but can be facilitated through behavioral, pharmacologic, or surgical interventions.

A systemic review of autologous fat grafting survival rate and related severe complications

OBJECTIVE

Clinical application of autologous fat grafting (AFG) is quickly expanding. Despite the widely acceptance, long-term survival rate (SR) of AFG remains a question not yet solved. Meanwhile, although rare, severe complications related to AFG including vision loss, stroke even death could be seen in the literature.

DATA SOURCES

A comprehensive research of PubMed database to June 2013 was performed according to guidelines of the American Society of Plastic Surgeons Fat Graft Task Force Assessment Methodology. Articles were screened using predetermined inclusion and exclusion criteria.

STUDY SELECTION

Data collected included patient characteristics, surgical technique, donor site, recipient site, graft amount, and quantified measurement methods. Patient cohorts were pooled, and SR was calculated. All the severe complications were also summarized according to the different clinical characteristics.

RESULTS

Of 550 articles, 16 clinical articles and 10 animal studies met the inclusion criteria and provided quantified measurement methods. Totally, 596 patients were included. SR varied from 34% to 82% in breast and 30-83% in the facial area. Nude mice were applied to investigate human fat grafting SR (38.3-52.5% after 15 weeks). Rabbits were commonly used to study animal AFG SR (14.00-14.56% after 1-year). Totally, 21 severe complications were reported, including death (2), stroke (10), vision loss (11, 8 of which accompanied with stroke), sepsis (3), multiple abscess (1) and giant fat necrotic cyst (2). Ten of these complications happened within 10 years.

CONCLUSIONS

There is no unified measurement method to evaluate fat graft SR until now and no clinical evidence to show better SR according to different donor and recipient cite. Body mass index change between pre- and postoperation may be the bias factor in evaluating fat SR. Fat embolisms of the ophthalmic artery and the middle cerebral artery are the most severe complication of AFG and still lack of effective treatment.

Histological findings of an autologous dermal fat graft implanted onto the pectoralis major muscle of a rat model

Background

The aim of this study was to investigate the maintenance of volume as a spacer by comparing vascular supply and apoptosis in an implanted autologous-free dermal fat graft (FDFG) and free fat graft (FFG). An autologous FDFG is a material used in plastic surgery and oncoplastic breast surgery that is ideal for immediate volume replacement after partial mastectomy because of its easy availability and minimal invasion of the donor site; however, immunohistochemical findings and survival procedures have not yet been reported.

Methods

An experimental protocol using a unique animal model was designed for the present study. The expression of vascular endothelial growth factor (VEGF) was measured in FDFGs and FFGs implanted onto the pectoral major muscle of Wistar rats. Thirty Wistar rats were divided into two groups and postoperatively 1, 2, 4, 8, and 16 weeks (POW1, 2, 4, 8, 16). Six samples from three rats in each group were used as control samples (POW0).

Results

The thickness of the implanted FDFG was not significantly different from the control sample at POW1, 2, 4, 8, and 16 between FDFG and FFG group; however, the thickness at POW8 and 16 was significantly lesser in the FFG group than in the control samples.

The average proportion of fatty tissue to whole tissue ranged from 34.2 to 48.6 % in the FDFG group and from 57.2 to 76.7 % in the FFG group during the observation period; however, there was no significant difference in the proportion of fatty tissue between these two groups. There were no significant differences between the average number of VEGF-positive cells in the FDFG group and the FFG group at POW1, 2, 4, 8, and 16. The average number of TUNEL-positive cells in the early period at POW1 was significantly lower in the FDFG group than in the FFG group.

Conclusions

This rat model was useful for investigating the mechanisms of angiogenesis, apoptosis, structure maintenance, and fibromatous changes. From the present experimental study, we believe that FDFG is one of the most convenient materials currently available to repair small defects at the time of BCS even in the clinical field.

Alternative injectable materials for vocal fold medialisation in unilateral vocal fold paralysis

BACKGROUND

Patients with unilateral vocal fold paralysis (UVFP) usually present with dysphonia, but can also be breathless and have problems with their swallowing. Speech and language therapy forms the initial mainstay of management in cases of UVFP, since up to 60% of cases will resolve spontaneously. If vocal fold paralysis persists surgery, in the form of injection medialisation, has been shown to be an effective intervention. What is currently unclear is which is the most effective material available for injection.

OBJECTIVES

To assess the effectiveness of alternative injection materials in the treatment of UVFP.

SEARCH METHODS

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the most recent search was 23 March 2012.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of injectable materials in patients with UVFP. The outcomes of interest were patient and clinician-reported improvement, and adverse events.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies from the search results and extracted data. We used the Cochrane 'Risk of bias' tool to assess study quality.

MAIN RESULTS

We identified no RCTs which met the inclusion criteria for this review. We excluded 18 studies on methodological grounds: 16 non-randomised studies; one RCT due to inadequate randomisation and inclusion of non-UVFP patients; and one RCT which compared two different particle sizes of the same injectable material.

AUTHORS' CONCLUSIONS

There is currently insufficient high-quality evidence for, or against, specific injectable materials for patients with UVFP. Future RCTs should aim to provide a direct comparison of the alternative materials currently available for injection medialisation.

Autologous fat transfer in velopharyngeal insufficiency: indications and results of a 25 procedures series

OBJECTIVE

To assess the efficiency of autologous fat transfer (AFT/Coleman procedure) in the management of velopharyngeal insufficiency (VPI).

SETTINGS

Tertiary academic center, retrospective case series over a 4 year period. Pre- and post-speech assessment by a speech pathologist using the Borel-Maisonny scale.

PATIENTS AND METHOD

Twenty-five (25) procedures were performed on 22 patients during the considered period. Mean age at surgery was 12.4 ± 4.1 years-old. Main associated conditions were 22q11 deletion (n=6 including 2 with cleft palate), isolated cleft palate (n=3), and Robin sequence (n=2). Indications were VPI grade 2a (n=5), 2b (n=11) and 3 (n=6), despite prolonged speech therapy (pre-op mean duration: 4.2 years) and previous surgery (velopharyngoplasty, n=13). Four patients had a contraindication of velopharyngoplasty (aberrant internal carotid arteries).

RESULTS AND CONCLUSION

Fat harvesting sites were umbilicus (n=23) and buttock (n=2). Mean injected fat volume was 7.8 ml, in the posterior wall of the pharynx (n=25) the soft palate (n=15), the peritonsillar arches (n=3), and the pre-existing flap (n=3). Mean follow-up was 17 months. Two patients relapsed once and one patient twice, requiring additional injections. Final post-operative examination 1 year after the last procedure showed an improvement of speech in 90% of cases (grade 1, n=2; 1/2a, n=5; 2a n=10; 2b, n=5). AFT is a safe technique indicated in the primary and secondary management of VPI, with stable results on speech. However, if a complete return to normal is difficult to achieve, its simplicity allows multiple procedures in the same patient.

Pulse dye and other laser treatments for vocal scar

PURPOSE OF REVIEW

Vocal fold scar is a challenging clinical problem, resulting in a spectrum of voice-related complaints. While there are a variety of treatment options available, it is rare to obtain outcomes similar to the perfectly normal voice. The pulsed dye and other lasers are an emerging treatment option for cutaneous scar and have shown promise for the treatment of vocal fold scarring. The purpose of this review is to summarize the theory, and describe clinical outcomes from both cutaneous and vocal fold scarring treated with lasers.

RECENT FINDINGS

There are a growing number of papers in the literature substantiating the use of pulsed dye and other lasers used to treat cutaneous scars. Some experimental models describe potential mechanisms of laser effect, which include the development of a sub-basement membrane cleavage plane, as well as up-regulation of proteins which may actively modulate continued fibrosis. One prospective pilot study of 11 patients with vocal fold scarring treated with the pulsed dye laser has also shown statistically significant improvement in subjective and objective voice measures, as well as laryngeal stroboscopy findings after treatment.

SUMMARY

The pulsed dye and other lasers have shown effectiveness and potential in treating cutaneous and vocal scarring.

Speech and magnetic resonance imaging results following autologous fat transplantation to the velopharynx in patients with velopharyngeal insufficiency

OBJECTIVE

To measure velopharyngeal closure with magnetic resonance imaging (MRI) and to evaluate speech when treating velopharyngeal insufficiency (VPI) with autologous fat transplantation to the velopharynx.

PATIENTS

Nine patients were recruited. Six patients had undergone cleft palate repair and subsequently developed VPI. Three were noncleft patients of which one had developed VPI after nasopharyngeal cancer treatment; another patient had developed VPI after combined adenotonsillectomy, and a third patient had VPI of unknown etiology.

MAIN OUTCOME MEASURE

Preoperative and 1-year postoperative MRIs were obtained during vocal rest and during phonation. Data measured were the velopharyngeal distance in the sagittal plane and the velopharyngeal gap area in the axial plane. Preoperative and 1-year postoperative audio recordings were blinded for scoring independently by three senior speech therapists.

RESULTS

When comparing preoperative and 1-year postoperative MRI during phonation we found a significant reduction of the median velopharyngeal distance from 4 to 0 mm (p = .011), and a significant reduction of the median velopharyngeal gap area from 42 to 34 mm(2) (p = .038). Nasal turbulence improved significantly (p = .011). Hypernasality/hyponasality and audible nasal emission did not change significantly.

CONCLUSIONS

Autologous fat transplantation to the velopharynx resulted in a significant reduction of the velopharyngeal distance and the velopharyngeal gap area during phonation, as measured by MRI. This was in accordance with a significant improvement in nasal turbulence. However, hypernasality and audible nasal emission did not change significantly and could not be correlated to the MRI findings.

Larynx: implants and stents

In the human larynx, implants a primarily used for the correction of glottis insufficiency. In a broader sense laryngeal stents may be considered as implants as well. Laryngeal implants can be differentiated into injectable and solid. The most important representatives of both groups are discussed in detail along with the respective technique of application. Laryngeal stents are primarily used perioperatively. Different types and their use are presented.

Elasticity measurements in scarred rabbit vocal folds using air pulse stimulation

This study aimed to compare vocal fold elasticity data from a new method for non-invasive analysis by stimulations of the mucosa with short air pulses. The depth of the mucosal deflections is measured with laser pulses by means of a special algorithm. Ten scarred New Zealand rabbit vocal folds and four normal rabbit folds were measured directly after sacrifice. The elastic data were compared to histological sections from the scarred vocal folds analysed by a pathologist. The results showed significantly lower elasticity (higher stiffness) values for the more scarred vocal folds as compared to samples with minor damage (P=0.03). It is concluded that the air pulse stimulation method is a promising tool for non-invasive quantification of vocal fold scarring.

Indirect low-intensity ultrasonic stimulation for tissue engineering

Low-intensity ultrasound (LIUS) treatment has been shown to increase mass transport, which could benefit tissue grafts during the immediate postimplant period, when blood supply to the implanted tissue is suboptimal. In this in vitro study, we investigated effects of LIUS stimulation on dye diffusion, proliferation, metabolism, and tropomyosin expression of muscle cells (C2C12) and on tissue viability and gene expression of human adipose tissue organoids. We found that LIUS increased dye diffusion within adjacent tissue culture wells and caused anisotropic diffusion patterns. This effect was confirmed by a hydrophone measurement resulting in acoustic pressure 150–341 Pa in wells. Cellular studies showed that LIUS significantly increased proliferation, metabolic activity, and expression of tropomyosin. Adipose tissue treated with LIUS showed significantly increased metabolic activity and the cells had similar morphology to normal unilocular adipocytes. Gene analysis showed that tumor necrosis factor-alpha expression (a marker for tissue damage) was significantly lower for stimulated organoids than for control groups. Our data suggests that LIUS could be a useful modality for improving graft survival in vivo.

Laryngeal complications after lipoinjection for vocal fold augmentation

OBJECTIVES/HYPOTHESIS

Vocal fold augmentation with autologous fat has been widely used for the last 15 years with varying success. Autologous fat is biocompatible, readily available, and easily harvested, making it a commonly used material for vocal fold augmentation. Although felt to be a relatively safe procedure, few studies have looked at the complication rate of lipoinjection for vocal fold augmentation.

STUDY DESIGN

Retrospective review.

METHODS

Ninety-eight vocal fold injections were performed at one institution from 1997 to 2008. The charts were reviewed retrospectively, and age, diagnosis, side of procedure, concurrent procedures, length of follow-up, and complications during or subsequent to the injection were recorded in a database. Patients were excluded if data was inadequate to make a determination regarding complication during or after lipoinjection.

RESULTS

Eighty-eight patients met the criteria for review with an average age of 57.4 years. The most common indications for injection were vocal fold paresis, vocal fold scarring, and presbylaryngeus. Mean follow-up was 20.2 months with a range of 0 months to 126 months. Overall, four laryngeal complications occurred (4.5%), including three over-injections (3.4%) leading to poor voice quality and one granuloma formation (1.1%). The over-injections were managed using cordotomy with fat removal, resulting in vocal improvement in all cases.

CONCLUSIONS

Although lipoinjection vocal fold augmentation is a safe procedure, over-injection of autologous fat is a risk. Lipoinjection for vocal fold augmentation can lead to over-injection with dysphonia in a small number of patients. The complications can be managed with lateral cordotomy and fat removal.

Intracordal fat assessment by 3-dimensional imaging after autologous fat injection in patients with thyroidectomy-induced unilateral vocal cord paralysis

BACKGROUND

Complications of thyroidectomy are the most frequent cause of unilateral vocal cord paralysis (UVCP) in Taiwan. Autologous fat injection for UVCP is a well-established procedure for temporary symptom relief. The aims of this study were to identify the long-term residual fat volume by 3-dimensional computed tomography (3-D CT) and to investigate the voice outcome.

METHODS

During this cross-sectional study, 28 consecutive patients who had undergone lipoinjection surgery for symptomatic UVCP resulting from thyroidectomy were enrolled. They received 3-D CT evaluations of the larynx and upper airway after lipoinjection surgery to assess the residual fat volume.

RESULTS

The mean duration from lipoinjection surgery to 3-D CT study was 26 months (range, 12-58). The mean residual fat volume remained consistent (0.39 +/- 0.35 mL; range, 0.01-1.6). The maximal phonation time, s/z ratio, jitter, and harmonic-to-noise ratio were significantly improved during follow-up.

CONCLUSION

Injected fat can survive chronically and provide clinically important improvement in voice in the patients with throidectomy-induced UVCP.

[Surgical voice rehabilitation in unilateral vocal fold paralysis]

Unilateral recurrent nerve paralysis leads to glottic insufficiency, significantly reducing vocal ability. Due to its unusually long course, the recurrent laryngeal nerve is prone to iatrogenic lesions involves many medical fields generally with little expertise in voice disorders. Whenever the etiology is uncertain, a complete diagnostic work-up is mandatory. Indirect laryngoscopy confirms the diagnosis. Laryngeal electromyography is of great value because it differentiates between paralysis and ankylosis of the cricoarytenoid joint. Moreover in many cases laryngeal electromyography yields a reliable prognosis of clinical outcome. While unfavorable results can be predicted with high accuracy, correct prognosis of complete recovery is more difficult. Speech therapy is the treatment of choice in cases of unilateral recurrent nerve palsy. Patients with persistent glottal gap may express the wish for surgical voice rehabilitation. Nowadays a broad spectrum of endoscopic and open approaches are available for this purpose. This review describes advanced techniques of voice-improving surgery available in specialized centers today.

The use of the pulse dye laser in the treatment of vocal fold scar: a preliminary study

OBJECTIVES/HYPOTHESIS

Dysphonia due to vocal fold scarring is a challenging problem to the laryngologist. Vocal fold scarring after radiation, phonosurgery, and laser cordectomy causes moderate to severe dysphonia. Surgical attempts at scar removal and voice restoration have limited success. Pulsed dye laser (PDL) treatment has been shown to be effective in softening scarred skin by serial office treatments. The objective of this preliminary study was to evaluate the use of the PDL in the management of patients with established vocal fold scar.

STUDY DESIGN

This is an Institutional Review Board-approved prospective study involving 11 patients. The causes of scarring were phonosurgery (n = 7), radiation (n = 2), and partial laryngectomy (n = 2). The subjects were evaluated pre- and postprocedure using the voice handicap index (VHI), laryngeal stroboscopy rating, voice recordings with acoustic and aerodynamic analysis, and self-evaluation.

METHODS

The PDL was applied with the fiberoptic delivery system by three treatments at 1-month intervals in the office setting. Each treatment endpoint was blanching of the treatment site.

RESULTS

: There were three women and eight men in our study group. Ten of 11 patients subjectively improved by self-rating. No patients were worse. VHI improved from 48.44 pretreatment to 35.55 at 6 months posttreatment (P < .05). The jitter at 6 months improved from 2.230% to 1.654% (P = NS) and shimmer improved from 3.679% to 3.196% (P = NS). The noise to harmonic ration improved from 0.1428 to 0.1316 (P = NS). The mean phonotory flow went from 0.177 to 0.254 L/S (P < .05). Three raters blinded to treatment sequence rated the posttreatment stroboscopy findings as better than pretreatment in a forced choice comparison, kappa score 0.903.

CONCLUSION

PDL is a safe and potentially promising treatment for established vocal fold scar. Subjectively, no patients were worse and 10 of 11 patients reported improved voice. There was improvement in the VHI, acoustic measures of shimmer and jitter, and stroboscopy findings. Further study using this approach in a larger cohort seems to be warranted.

Lipoaugmentation of the vocal folds: a survey on alternative donor sites for graft harvesting

Lipoaugmentation is a treatment option for patients suffering from glottic insufficiency. Autologous fat is a nearly ideal material for vocal-fold augmentation from the view of biocompatibility and viscoelasticity, but there is still the problem of high graft resorption. As distribution and biological behavior of fatty tissue is very different in the human body, the aim of the study was to elucidate possible donor sites with respect to the quantity of harvested fat, the surgical accessibility to the region, the donor site morbidity and possibility of aesthetic defects and the quality of harvested tissue. Possible donor sites for harvesting were examined by magnetic resonance imaging in thirty-five patients with special emphasis to the buccal fat pad, the neck, the dorsolateral side of the proximal upper extremity, the subcutaneous layer of the abdominal wall, the superficial trochanteric region, the medial thigh, and the infrapatellar fat pad. Identified regions that failed to be chosen into consideration because of an elaborate surgical approach (superficial axillary's space, ischio-anal fossa, subcutaneous layer of buttock, popliteal fossa) were not taken into consideration. The mean volume of the buccal fat was 3.994 cm(3); the average thickness of the fat at the level of C7 was 1.721 cm, the mean value in the upper extremities was 1.913 cm laterally and 1.275 cm dorsally. The subcutaneous fat of the abdominal wall was divided into a superficial compartment (mean: 1.527 cm) and a deep one (average: 3.545 cm). In the superficial trochanteric region, the mean thickness was 2.536 cm, in the medial thigh 2.127 cm; the mean volume of the infrapatellar fat pad was 20.198 cm(3). All regions of interest showed reproducible and sufficient amounts of harvestable tissue, we found significant intersexual differences in dorsolateral side of the upper arm, subcutaneous layer of the abdominal wall and superficial trochanteric region. When harvesting subcutaneous tissue of the abdominal wall, grafts of the deep layer should be preferred, in the upper extremity the deep, muscle-neighbored parts. An alternative method is the surgically accessible fat of the neck. Solid fat pads could be harvested from the buccal region or the infrapatellar fat.