Laryngeal Cartilage Regeneration of Nude Rats by Transplantation of Mesenchymal Stem Cells Derived from Human-Induced Pluripotent Stem Cells.

Previous studies transplanted human-induced pluripotent stem cells (hiPSCs)-derived mesenchymal stem cells (iMSCs) into thyroid cartilage defect of X-liked severe combined immunodeficiency (X-SCID) rats and confirmed transplanted cell survival and cartilage regeneration. Thus, this study aimed to investigate the contribution of iMSC transplantation to thyroid cartilage regeneration of nude rats. iMSCs were induced from hiPSCs via a neural crest cell lineage. Then, clumps formed from an iMSC/extracellular matrix complex were transplanted into thyroid cartilage defects in nude rats. The larynx was removed and histological and immunohistochemical analyses were performed 4 or 8 weeks after the transplantation. Human nuclear antigen (HNA)-positive cells were observed in 11 of 12 (91.7%) rats, which indicated that transplanted iMSCs survived in thyroid cartilage defects in nude rats. HNA-positive cells co-expressed SOX9, and type II collagen was identified around HNA-positive cells in 8 of 12 rats (66.7%), which indicated cartilage-like regeneration. Cartilage-like regeneration in nude rats in this study was comparable to the previous report on X-SCID rats (HNA-positive cells were observed in all 14 rats and cartilage-like regeneration was observed in 10 of 14 rats). This result suggests that nude rats could be an alternative to X-SCID rats in thyroid cartilage regeneration experiments using iMSCs, and this nude rat cartilage transplantation model may develop cartilage regeneration research concerning fewer problems such as infection due to immunosuppression.

Intraoperative computed tomography imaging for laryngoplasty.

OBJECTIVES: Intraoperative cone beam computed tomography (CBCT) imaging has the potential to facilitate the surgical procedure. The current preliminary retrospective chart review investigated the benefits of intraoperative CBCT during laryngoplasty. METHOD: This study examined 26 cases that underwent intraoperative CBCT imaging during laryngoplasty, with one patient who counted twice due to first and revision surgery. The visual quality of structures of interest (glottal shape, thyroid cartilage, arytenoid cartilage, and implants) was determined using intraoperative CBCT during laryngoplasty. Each patient also underwent an aerodynamic assessment. RESULTS: CBCT provided unique information, such as surgical landmarks in severe scarring, the subglottal shape, and the rotation angle of the arytenoid cartilage during arytenoid adduction. Nonetheless, 26.9% (7 of 26) of cases were affected by motion artifact, due to the long acquisition time. When motion artifact-negative cases were evaluated, 100% of glottal shape and more than 89% of thyroid cartilage were well visualized. All arytenoids were well-visualized in patients ≥ 50 years of age and without motion artifact, while CBCT failed to visualize the arytenoids in 2 of 4 patients who were < 50 years, due to the lack of calcifications. After medialization surgery, the yields of improved maximal phonation times (MPTs) in the motion artifact-negative and -positive groups were 8.7 sec and 3.4 sec, respectively (p = 0.032; Welch's t test). This comparison indicates intraoperative CBCT would contribute in MPT improvement, if CBCT is taken in measurable quality. CONCLUSION: The potential benefits of intraoperative CBCT during laryngoplasty were demonstrated. A corollary, prospective study is warranted to further confirmation.

A retrospective analysis of revision framework surgeries for unilateral vocal fold paralysis / Análise retrospectiva das cirurgias de revisão do arcabouço laríngeo para paralisia unilateral de prega vocal

Abstract Introduction Revision framework surgeries might be required for unilateral vocal fold paralyses. However, outcomes and indications of revision surgeries have not been adequately documented. For a better understanding of indications for the procedure and to help in achieving better vocal outcomes, we performed a retrospective chart review of patients who underwent revision framework surgeries for unilateral vocal fold paralysis. Objectives This study aimed to present clinical features of patients who underwent revision framework surgeries for the treatment of unilateral vocal fold paralysis. Methods Of the 149 framework surgeries performed between October 2004 and October 2019, 21 revision framework surgeries were performed in 19 patients. Self-assessments by patients using the voice handicap index-10 questionnaire, and objective aerodynamic and acoustic assessments performed pre- and post-operatively were analyzed using the Wilcoxon's signed-rank test for paired comparisons. Results Undercorrection was indicated as reasons for revision surgeries in all cases. The revision techniques included type I thyroplasty, type IV thyroplasty, and arytenoid adduction, and revision surgeries were completed without any severe complication in all cases. Pre- and post-operative voice handicap index-10 scores were obtained in 12 cases, and other parameters were evaluated in 18 cases. Significant improvements were observed in voice handicap index-10 scores, maximum phonation time, mean flow rate, Current/Direct Current ratio, and pitch perturbation quotient. Conclusion Undercorrection was observed in all patients who underwent revision framework surgeries for unilateral vocal fold paralysis, and the initial assessment and planning are thought to be important in order to avoid revision surgeries. Revision surgeries were performed safely in all cases, and significantly improved vocal outcomes were observed, even after multiple procedures. Revision surgery should be considered for patients with unsatisfactory vocal functions after primary framework surgeries for unilateral vocal fold paralysis.

Resumo Introdução As cirurgias de revisão do arcabouço laríngeo podem ser necessárias em casos de paralisia unilateral de prega vocal. Entretanto, os resultados e as indicações das cirurgias de revisão não têm sido documentados de forma adequada. Para melhor compreensão das indicações do procedimento e para auxiliar na obtenção de melhores resultados vocais, fizemos uma revisão retrospectiva dos prontuários de pacientes submetidos a cirurgias de revisão do arcabouço laríngeo em paralisia unilateral de prega vocal. Objetivos Apresentar as características clínicas de pacientes submetidos a cirurgias de revisão do arcabouço laríngeo para tratamento de paralisia unilateral de prega vocal. Método Das 149 cirurgias de revisão do arcabouço laríngeo feitas entre outubro de 2004 e outubro de 2019, 21 cirurgias de revisão do arcabouço laríngeo foram feitas em 19 pacientes. As autoavaliações feitas pelos pacientes com o questionário voice handicap index‐10 e avaliações aerodinâmicas e acústicas objetivas feitas no pré e pós‐operatório foram analisadas com o teste de postos sinalizados de Wilcoxon para comparações pareadas. Resultados A hipocorreção foi apontada como o motivo das cirurgias de revisão em todos os casos. As técnicas de revisão incluíram tireoplastia tipo I, tireoplastia tipo IV e adução de aritenoide. As cirurgias de revisão foram feitas sem qualquer complicação grave em todos os casos. Os escores do questionário voice handicap index‐10 pré e pós‐operatórios foram obtidos em 12 casos e outros parâmetros foram avaliados em 18 casos. Melhorias significativas foram observadas nos escores do questionário, no tempo máximo de fonação, taxa de fluxo médio, relação antes/depois e no quociente de perturbação do pitch. Conclusão Hipocorreção foi observada em todos os pacientes submetidos a cirurgias de revisão do arcabouço laríngeo para paralisia unilateral de prega vocal e a avaliação inicial e o planejamento são considerados importantes para evitar cirurgias de revisão. As cirurgias de revisão foram feitas com segurança em todos os casos e melhoria significativa dos resultados vocais foi observada mesmo após múltiplos procedimentos. A cirurgia de revisão deve ser considerada para pacientes com funções vocais insatisfatórias após cirurgia primária do arcabouço laríngeo para paralisia unilateral de prega vocal.

Predictive factors for false negatives following sentinel lymph node biopsy in early oral cavity cancer.

Prophylactic elective neck dissection (ND) with navigation surgery using radioisotope-based sentinel lymph node biopsy (SLNB) is non-inferior to elective ND in terms of survival but has an advantage in postoperative functional disability. We conducted a subgroup analysis to identify predictive factors for false-negative (FN)-SLNB in patients with early oral cavity cancer. This study is a supplementary analysis using the dataset of a previously reported randomized clinical trial on SLN navigation surgery for oral cancers. This study investigated the association of clinical and SLN-related factors with false-negative cases in the SLNB group. From 2011 to 2016, 275 patients were enrolled and randomly assigned to the ND and SLNB study groups, with 134 patients assigned to the SLNB group. In the SLNB group, seven cases with negative SLNs and neck recurrences were judged as FN-SLNBs according to the general definition. The number of detected SLNs with and without adjusting for the propensity score was significantly associated with FNs in the logistic analysis. FN-SLNB was associated with the number of identified SLNs, suggesting the need for careful postoperative monitoring for neck recurrence in patients with one or two identified SLNs after acquiring sufficient experience in the identification technique.

A retrospective analysis of revision framework surgeries for unilateral vocal fold paralysis.

INTRODUCTION: Revision framework surgeries might be required for unilateral vocal fold paralyses. However, outcomes and indications of revision surgeries have not been adequately documented. For a better understanding of indications for the procedure and to help in achieving better vocal outcomes, we performed a retrospective chart review of patients who underwent revision framework surgeries for unilateral vocal fold paralysis. OBJECTIVES: This study aimed to present clinical features of patients who underwent revision framework surgeries for the treatment of unilateral vocal fold paralysis. METHODS: Of the 149 framework surgeries performed between October 2004 and October 2019, 21 revision framework surgeries were performed in 19 patients. Self-assessments by patients using the voice handicap index-10 questionnaire, and objective aerodynamic and acoustic assessments performed pre- and post-operatively were analyzed using the Wilcoxon's signed-rank test for paired comparisons. RESULTS: Undercorrection was indicated as reasons for revision surgeries in all cases. The revision techniques included type I thyroplasty, type IV thyroplasty, and arytenoid adduction, and revision surgeries were completed without any severe complication in all cases. Pre- and post-operative voice handicap index-10 scores were obtained in 12 cases, and other parameters were evaluated in 18 cases. Significant improvements were observed in voice handicap index-10 scores, maximum phonation time, mean flow rate, Current/Direct Current ratio, and pitch perturbation quotient. CONCLUSION: Undercorrection was observed in all patients who underwent revision framework surgeries for unilateral vocal fold paralysis, and the initial assessment and planning are thought to be important in order to avoid revision surgeries. Revision surgeries were performed safely in all cases, and significantly improved vocal outcomes were observed, even after multiple procedures. Revision surgery should be considered for patients with unsatisfactory vocal functions after primary framework surgeries for unilateral vocal fold paralysis.

In vivo regeneration of rat laryngeal cartilage with mesenchymal stem cells derived from human induced pluripotent stem cells via neural crest cells.

The laryngotracheal cartilage is a cardinal framework for the maintenance of the airway for breathing, which occasionally requires reconstruction. Because hyaline cartilage has a poor intrinsic regenerative ability, various regenerative approaches have been attempted to regenerate laryngotracheal cartilage. The use of autologous mesenchymal stem cells (MSCs) for cartilage regeneration has been widely investigated. However, long-term culture may limit proliferative capacity. Human-induced pluripotent stem cell-derived MSCs (iMSCs) can circumvent this problem due to their unlimited proliferative capacity. This study aimed to investigate the efficacy of iMSCs in the regeneration of thyroid cartilage in immunodeficient rats. Herein, we induced iMSCs through neural crest cell intermediates. For the relevance to prospective future clinical application, induction was conducted under xeno-free/serum-free conditions. Then, clumps fabricated from an iMSC/extracellular matrix complex (C-iMSC) were transplanted into thyroid cartilage defects in immunodeficient rats. Histological examinations revealed cartilage-like regenerated tissue and human nuclear antigen (HNA)-positive surviving transplanted cells in the regenerated lesion. HNA-positive cells co-expressed SOX9, and type II collagen was identified around HNA-positive cells. These results indicated that the transplanted C-iMSCs promoted thyroid cartilage regeneration and some of the iMSCs differentiated into chondrogenic lineage cells. Induced MSCs may be a promising candidate cell therapy for human laryngotracheal reconstruction.

A novel method for live imaging of human airway cilia using wheat germ agglutinin.

Multiciliated epithelial cells in the airway are essential for mucociliary clearance. Their function relies on coordinated, metachronal and directional ciliary beating, appropriate mucus secretion and airway surface hydration. However, current conventional methods for observing human airway ciliary movement require ciliated cells to be detached from airway tissues. Determining the directionality of cilia is difficult. We developed a novel method to stain airway epithelial cilia to observe their movement without releasing ciliated cells. Human tracheae were obtained from patients (n = 13) who underwent laryngectomies to treat malignancies or swallowing disorders. The tracheae were treated with fluorescently labeled wheat germ agglutinin, which interacts with the acidic mucopolysaccharides present on the cilia. Epithelial surfaces were observed using an epi-fluorescence microscope equipped with a water-immersion objective lens and a high-speed camera. Ciliary movement was observable at 125 fps (13/13 samples). Ciliated cells in close proximity mostly exhibited well-coordinated ciliary beats with similar directionalities. These findings indicated that wheat germ agglutinin renders ciliary beats visible, which is valuable for observing human airway ciliary movements in situ.

Adipose-derived mesenchymal stromal cells prevented rat vocal fold scarring.

OBJECTIVES/HYPOTHESIS: This study aimed to reveal the effects of adipose-derived mesenchymal stromal cells (ASCs) on prevention of vocal fold scarring by investigating how the immediate ASCs transplantation into the injured rat vocal fold affect the levels of gene transcription and translation. STUDY DESIGN: Prospective animal experiments with controls. METHODS: ASCs harvested from green fluorescent protein transgenic rat (ASCs group) or saline (sham group) were injected into the thyroarytenoid muscle of Sprague-Dawley rats immediately after stripping the vocal fold. For histological examinations, larynges were extirpated at 3, 14, and 56 days after the injection. Quantitative real-time polymerase chain reaction (PCR) analyses were performed at 3 and 14 days after the injection. RESULTS: Transplanted ASCs were detected only in larynges at day 3. At days 14 and 56, histological examination showed significantly higher amounts of hyaluronic acid and lower deposition of collagen in the ASCs group compared to the sham group. Real-time PCR revealed that the ASCs group showed low expression of procollagen (Col)1a1, Col1a3, matrix metalloproteinase (Mmp)1 and Mmp8 in each time points. The ASCs group showed high expression of fibroblast growth factor (Fgf)2 and Hepatocyte growth factor (Hgf) compared to the sham group at day 14. CONCLUSIONS: ASCs increased expressions of Fgf2 and Hgf, and suppressed excessive collagen deposition during vocal fold wound healing. Given the fact that ASCs survived no more than 14 days, ASCs were thought to induce upregulations of growth factors' genes in surrounding cells. These results suggested that ASCs have potential to prevent vocal fold scarring. LEVEL OF EVIDENCE: NA. Laryngoscope, 128:E33-E40, 2018.

The effects of concurrent chemoradiation therapy to the base of tongue in a preclinical model.

OBJECTIVES/HYPOTHESIS: To develop a clinically relevant model of oropharyngeal concurrent chemoradiation therapy (CCRT) in order to quantify the effects of CCRT on tongue function and structure. CCRT for advanced oropharyngeal cancer commonly leads to tongue base dysfunction and dysphagia. However, no preclinical models currently exist to study the pathophysiology of CCRT-related morbidity, thereby inhibiting the development of targeted therapeutics. STUDY DESIGN: Animal model. METHODS: Twenty-one male Sprague-Dawley rats were randomized into three groups: 2 week (2W), 5 month (5M), and control (C). The 2W and 5M animals received cisplatin, 5-fluorouracil, and five fractions of 7 Gy to the tongue base; the C animals received no intervention. In vivo tongue strength and displacement, as well as hyoglossus muscle collagen content, were assessed. Analyses were conducted 2 weeks or 5 months following completion of CCRT in the 2W and 5M groups, respectively. RESULTS: Peak tetanic and twitch tongue forces were significantly reduced in both 2W and 5M animals compared to controls (tetanic: P = .0041, P = .0089, respectively; twitch: P = .0201, P = .0020, respectively). Twitch half-decay time was prolonged in 2W animals compared to controls (P = .0247). Tongue displacement was significantly reduced across all testing parameters in 5M animals compared to both the C and 2W groups. No differences in collagen content were observed between experimental groups. CONCLUSIONS: The current study is the first to describe a preclinical model of CCRT to the head and neck with an emphasis on clinical relevance. Tongue strength decreased at 2 weeks and 5 months post-CCRT. Tongue displacement increased only at 5 months post-CCRT. Fibrosis was not detected, implicating alternative causative factors for these findings. LEVEL OF EVIDENCE: NA Laryngoscope, 1783-1790, 2018.

Stem Cell-Mediated Paracrine Signaling Alters Fibroplasia in Human Vocal Fold Fibroblasts in Vitro.

OBJECTIVES: Interactions between mesenchymal stem cells (MSCs) and native vocal fold fibroblasts (VFFs) have not been described in spite of promising preliminary data regarding the effects of MSCs on vocal fold repair in vivo. The current study employed a conditioned media (CM) model to investigate the paracrine effects of bone marrow-derived mesenchymal stem cells (BMSCs) on VFFs. METHODS: Human VFFs were treated with transforming growth factor-ß1 (TGF-ß1; 10 ng/mL), CM from human BMSCs following 48 hours of TGF-ß1 stimulation, or CM+TGF-ß1. Proliferation, immunocytochemistry for alpha smooth muscle actin (αSMA), migration, and collagen gel contraction were quantified as well as transcription of components of the TGF-ß signaling pathway. RESULTS: Transforming growth factor-ß1 accelerated proliferation and induced αSMA in VFFs; these effects were suppressed with CM ( P = .009, P < .001, respectively). The CM+TGF-ß1 condition increased cell migration ( P = .02) and decreased gel contraction; CM+TGF-ß1 also inhibited TGF-ß signaling via significant upregulation of NR4A1 as well as downregulation of S MAD3 and TGF-ß1 relative to TGF-ß1 stimulation in the absence of CM ( P = .002, P < .001, and P = .005, respectively). CONCLUSIONS: Conditioned media affected many profibrotic cell activities in TGF-ß1-stimulated VFFs, likely related to altered TGF-ß signaling. These data provide preliminary insight regarding the antifibrotic effects of MSCs and further support their progression to clinical utility.

Imiquimod Injection to Rabbit Vocal Folds: A Preliminary, Preclinical Investigation.

Objective Given the recalcitrant nature of recurrent respiratory papillomatosis, targeted therapies to reduce disease burden are fundamental to improved patient care paradigms. We seek to demonstrate the safety of imiquimod injection into vocal fold mucosa by evaluating the degree of laryngeal edema, histopathologic changes to vocal fold structure, and serologic interferon α (IFNα) levels following injection. Study Design Preclinical. Setting Academic institution. Subjects and Methods Six New Zealand White rabbits underwent unilateral injection of 100 µg of sterile imiquimod (1 µg/µL), with 100 µL of normal saline injected into the contralateral vocal fold. Direct laryngoscopy was performed on days 3, 7, and 30 following injection. Larynges from 3 rabbits were harvested on postinjection day 7 for histologic analysis. The remaining 3 rabbit larynges were harvested on day 30. Serial serum samples were drawn for IFNα quantification via immunoassay. Results No signs of respiratory distress were observed at any point. Vocal fold appearance was not clinically divergent between imiquimod and control conditions via serial direct laryngoscopic evaluation. No inflammatory lesions or scarring were identified following injection. Histology showed no signs of acute inflammatory processes or changes in the control or imiquimod injection groups. Serum IFNα increased at days 3 and 7 following imiquimod injection ( P < .0001 and P = .0368, respectively), before returning to baseline by day 14. Conclusions Vocal fold imiquimod injection did not result in notable morbidity in this preclinical model. However, serum IFNα concentrations increased transiently. These data are critical to advance the therapeutic utility of this compound, particularly in the setting of recurrent respiratory papillomatosis.

Mesenchymal stem cells have antifibrotic effects on transforming growth factor-ß1-stimulated vocal fold fibroblasts.

OBJECTIVES/HYPOTHESIS: Mesenchymal stem cells (MSCs) hold therapeutic promise for vocal fold scar, yet the precise mechanism(s) underlying tissue level changes remain unclear. We hypothesize that MSCs interact with native fibroblasts to favorably affect healing. Furthermore, we hypothesize that these interactions vary based on MSC source. METHODS: Vocal fold fibroblasts (VFFs), adipose-derived stem cells, and bone marrow-derived stem cells (BMSCs) were extracted from Sprague-Dawley rats; and a coculture model was employed culturing VFFs ± transforming growth factor (TGF-ß1) (10 ng/mL) ± MSCs. Monoculture MSCs were also prepared as a control. Both extracellular matrix (ECM) and components of the TGF-ß signaling pathway were analyzed via polymerase chain reaction and western blotting. RESULTS: Significantly decreased TGF-ß1 mRNA and α-smooth muscle actin protein was observed in VFFs in response to TGF-ß1 in the coculture with both MSCs (P < 0.05, P < 0.01). BMSCs significantly downregulated collagen I (P < 0.05), collagen III (P < 0.05), Smad3 (P < 0.01), and TGF-ß1 receptor I (P < 0.01) mRNA in VFFs. Hyaluronic synthase-1 and 2 increased in cocultured BMSCs when compared with monocultured BMSCs at baseline and in response to TGF-ß1 (P < 0.01). CONCLUSION: MSCs had a favorable effect on ECM regulation as well as suppression of TGF-ß1 signaling in VFF. Bidirectional paracrine signaling was also observed as VFFs altered ECM regulation in MSCs. These data provide insight into the regenerative effects of MSCs and provide a foundation for clinical application. LEVEL OF EVIDENCE: NA Laryngoscope, 127:E35-E41, 2017.

Development of an in vivo model of laryngeal burn injury.

OBJECTIVES/HYPOTHESIS: Inhalation injury significantly increases morbidity and mortality in burn patients. Approximately one in five burn patients have acute injury to the larynx, trachea, and/or lungs-and as many as 70% have long-term laryngeal abnormalities. Although inhalation injury to the lung has been studied extensively, no models exist to study these insults to the larynx. As such, we developed an in vivo rabbit model to create precise and reproducible laryngeal burn with resultant tissue damage as a foundation for interventional studies. METHODS: Following tubeless tracheotomy, a custom temperature-control device was employed to apply heated air (70°C-80°C, 150°C-160°C, or 310°C-320°C) ± smoke derived from unbleached cotton to the larynx, endoscopically, minimizing adjacent tissue damage in six rabbits. Pain, nutrition, and level of activity were monitored. Direct laryngoscopy and histological examination were performed 24 hours following insult. RESULTS: All animals survived injury with appropriate pain control; oral intake was initiated and all were adequately ventilating via tracheostomy. Burn sequelae were noted under direct visualization 24 hours after injury, and graded levels of edema and tissue damage were observed as a function of temperature. Edema obstructed true vocal fold visualization at increased temperatures. These injury patterns correlated with graded tissue damage on histology. CONCLUSION: We created an in vivo model of laryngeal burn injury employing a custom burn device resulting in graded tissue injury. This model is critical for investigation of the mechanisms underlying burn injury, and ultimately, the development and evaluation of therapies for this challenging population. LEVEL OF EVIDENCE: NA Laryngoscope, 127:186-190, 2017.

Voice Outcome in Patients Treated With Endoscopic Laryngopharyngeal Surgery for Superficial Hypopharyngeal Cancer.

OBJECTIVES: Endoscopic laryngopharyngeal surgery (ELPS) is a minimally invasive transoral surgery that was developed to treat superficial larygo-pharyngeal cancer, in which a mucosal lesion is resected transorally while preserving deeper structures by subepithelial injection. The purpose of this retrospective study is to evaluate voice outcome in patients who underwent ELPS for superficial hypopharyngeal cancer. As important structures in producing voice, such as intrinsic laryngeal muscles, their fascia, and recurrent laryngeal nerve, are located in the medial side of the piriform sinus and the postcricoid region of the hypopharynx, we focused on patients with cancer lesions involving these regions. METHODS: From April 2010 to March 2011, 25 consecutive patients with superficial laryngopharyngeal cancer were treated with ELPS at Kyoto University Hospital. Among the 25 patients, 11 patients with cancer lesions on the medial side of the piriform sinus or the postcricoid area were studied. Preoperative and postoperative voice functions including maximum phonation time (MPT), mean flow rate (MFR), jitter, shimmer, soft phonation index (SPI), and noise-to-harmonic ratio (NHR), were compared retrospectively. RESULTS: Five of 11 cancer lesions had submucosal invasion and no lesion had invaded the muscular layer pathologically. T stage was classified as Tis in 5 cases, T1 in 4 cases, and T2 in 2 cases. All lesions involved the medial side of the piriform sinus and 2 also involved the postcricoid area. Vocal fold movement was normal in all cases after the surgery. Average preoperative and postoperative values for MPT, MFR, jitter, shimmer, SPI, and NHR, were 22.7 seconds and 23.4 seconds, 165 mL/sec and 150 mL/sec, 1.53% and 1.77%, 3.82% and 5.17%, 35.5 and 36.6, and 0.13% and 0.14%, respectively. There was no statistical difference between preoperative and postoperative data for all values examined. CONCLUSION: ELPS is useful in preserving voice function in the treatment of superficial hypopharyngeal cancer. Preserving the deeper structures including intrinsic muscles and their fascia may be important for preserving voice function as long as the lesions are superficial.

Photocoagulation therapy for laryngeal dysplasia using angiolytic lasers.

In the management of laryngeal pre-cancerous lesions such as dysplasia or carcinoma in situ (CIS), it is important that lesion regression occur without any complications. As a minimally invasive treatment option, photocoagulation therapy using angiolytic lasers has been attracting attention. Therapeutic effects have been reported for this type of treatment, however, vocal function after treatment has not been well discussed. In this retrospective case series, we examined the therapeutic effects of photocoagulation therapy on laryngeal dysplasia and the impact on vocal function. Twenty-four patients with laryngeal dysplasia or CIS were treated with photocoagulation therapy using angiolytic lasers. Two patients were treated under general anesthesia, the remaining 22 patients were treated with topical anesthesia. Before and after treatment the extent of the lesion and vocal function was evaluated by endoscopic examination and acoustic and aerodynamic analyses, respectively. More than 50 % disease regression was observed in 20 of 24 patients. Acoustic and aerodynamic analyses revealed improvement in pitch perturbation quotient with no impairment in other parameters. Photocoagulation therapy using angiolytic lasers has proven to be feasible and safe for the treatment of laryngeal dysplasia.

Comparison of ASCs and BMSCs combined with atelocollagen for vocal fold scar regeneration.

OBJECTIVES/HYPOTHESIS: Vocal fold scar remains a therapeutic challenge. Mesenchymal stromal cells (MSCs) are promising tools for regenerative medicine. Nevertheless, few in vivo studies have directly compared various sources of MSCs. The aim of this study was to investigate the therapeutic potential of adipose-derived stromal cells (ASCs) in comparison with bone marrow-derived stromal cells (BMSCs) for vocal fold regeneration. STUDY DESIGN: Prospective animal experiments with controls. METHODS: Two months after stripping of the lamina propria, 18 beagles were divided into four implantation groups: atelocollagen alone (collagen group), atelocollagen with BMSCs (BMSC-collagen), atelocollagen with ASCs (ASC-collagen), or a sham-treated group. One or 6 months after implantation, vibratory and histological examinations were performed. RESULTS: Mucosal vibration was significantly improved in both of the MSC-implanted groups compared with the sham-treated group, whereas only the ASC-collagen group showed a significantly smaller glottal gap than the collagen group. Moreover, in the ASC-collagen group, a significant reduction of collagen density was observed compared to the sham-treated group, and there was a trend for better restoration of hyaluronic acid (HA). Implanted MSCs were detected 1 month postimplantation; however, none survived 6 months postimplantation. CONCLUSIONS: Although implantation of an atelocollagen sponge and ASCs into vocal fold scars induced vibratory recovery comparable to that of BMSCs, ASCs might have more potential in terms of restoration of HA and suppression of excessive collagen deposition. LEVEL OF EVIDENCE: NA Laryngoscope, 126:1143-1150, 2016.

Comparison of vocal outcomes after angiolytic laser surgery and microflap surgery for vocal polyps.

OBJECTIVE: The microflap technique is a standard procedure for the treatment of vocal fold polyps. Angiolytic laser surgery carried out under topical anesthesia is an alternative method for vocal polyp removal. However, it is not clear whether angiolytic laser surgery has the same effects on vocal outcomes as the microflap technique because of a lack of studies comparing both procedures. In the current study, vocal outcomes after both procedures were compared to clarify the effects of angiolytic laser surgery for vocal polyp removal. METHODS: Vocal outcomes were reviewed for patients who underwent angiolytic laser surgery (n=20, laser group) or microflap surgery (n=34, microflap group) for vocal polyp removal. The data analyzed included patient and lesion characteristics, number of surgeries required for complete resolution, and aerodynamic and acoustic examinations before and after surgery. RESULTS: In the laser surgery group, complete resolution of the lesion was achieved with a single procedure in 17 cases (85%) and with two procedures in 3 cases (15%). Postoperative aerodynamic and acoustic parameters demonstrated significant improvement compared to preoperative parameters in both the laser surgery group and the microflap surgery group. There were no significant differences in any postoperative aerodynamic and acoustic parameters between the two groups. CONCLUSION: The current retrospective study demonstrated that angiolytic laser surgery achieved complete resolution of vocal polyps within two procedures. Postoperative effects on aerodynamic and acoustic functions were similar to those after microflap surgery.

Multidimensional Analysis on the Effect of Vocal Function Exercises on Aged Vocal Fold Atrophy.

OBJECTIVES: Age-related voice change is characterized as weak, harsh, and breathy. These changes are caused by histologic alteration of the lamina propria of the vocal fold mucosa as well as atrophy of the thyroarytenoid muscle. Several therapeutic strategies involving laryngeal framework surgery and injection laryngoplasty have been tried, but effects have been limited. Vocal function exercises (VFE) have been used to treat age-related vocal fold atrophy although the effectiveness has been shown with limited analysis. The present study aims to determine the effectiveness of VFE for the treatment of aged atrophy using multidimensional analysis. STUDY DESIGN: This is a retrospective study. METHODS: Sixteen patients with vocal fold atrophy aged 65-81 years underwent voice therapy using VFE. Six patients with vocal fold atrophy aged 65-85 years were involved as a historical control group. The grade, roughness, breathiness, asthenia, strain (GRBAS) scale, stroboscopic examinations, aerodynamic assessment, acoustic analysis, and Voice Handicap Index-10 (VHI-10) were performed before and after VFE. Normalized mucosal wave amplitude (NMWA), normalized glottal gap (NGG), and bowing index (BI) were measured by image analysis during stroboscopic examinations. RESULTS: After VFE, significant improvements were shown in GRBAS, maximum phonation time, jitter, NMWA, NGG, and VHI-10 although BI has not changed significantly. There were no significant improvements in the historical control. CONCLUSIONS: The data suggest that VFE produces significant improvement in subjective, objective, and patient self-evaluation and deserves further attention as a treatment for aged atrophy of the vocal fold. It was also suggested that VFE does not improve the vocal fold bowing but may improve muscular function during voicing.

Adipose-derived stem cells versus bone marrow-derived stem cells for vocal fold regeneration.

OBJECTIVES/HYPOTHESIS: Vocal fold scarring presents therapeutic challenges. Recently, cell therapy with mesenchymal stromal cells has become a promising approach. The aim of this study was to compare the therapeutic potential of adipose-derived stem cells (ASC) with bone marrow-derived stem cells (BMSC) for vocal fold regeneration. STUDY DESIGN: Prospective animal experiments with controls. METHODS: The vocal folds of Sprague-Dawley rats were unilaterally injured. Two months after injury, rats were treated with a local injection of ASC (ASC group), BMSC (BMSC group), or saline (sham-treated group). The GFP-labeled ASC and BMSC were extracted from CAG-EGFP rats. Larynges were harvested for histological and immunohistochemical examinations 1 and 3 months posttransplantation and for quantitative real-time polymerase chain reaction (PCR) 1 month posttransplantation. RESULTS: After 1 month, no surviving cells from the transplant were detected. Histological examination showed significantly increased hyaluronic acid (HA) and decreased dense collagen deposition in both ASC and BMSC groups compared to shams 1 and 3 months after treatment. Real-time PCR revealed that hyaluronan synthase 1 (Has1) and Has2 were upregulated in only the ASC group compared with the sham-treated group. Fibroblast growth factor 2 (basic) (Fgf2), hepatocyte growth factor (Hgf) and Has3 were upregulated in both cell transplantation groups. ASC seemed to upregulate Hgf more than did BMSC. CONCLUSIONS: The regenerative effects of ASC and BMSC transplantation were found to be similar for the restoration. It is suggested that ASC might have more potential because of better recovery of HA, a superior antifibrotic effect, and the upregulation of Hgf. LEVEL OF EVIDENCE: N/A.

Early-onset postirradiation sarcoma of the tongue after pseudotumor phase.

Radiation-induced sarcoma usually develops after an interval of more than 10 years from the completion of radiation therapy to the diagnosis of secondary sarcoma. However, the theory of radiation-induced transformation does not rule out postirradiation sarcomas with a short latency period. We experienced the case of a patient with postirradiation leiomyosarcoma of the tongue, which occurred 19 months after he had received chemoradiotherapy. Besides the short latency period, a pseudotumor stage developed between the time of radiation exposure and the development of leiomyosarcoma. In this article, we also describe an immunohistochemical approach to diagnose leiomyosarcoma and the efficacy of a gemcitabine and docetaxel regimen.