著者

鈴木 真輔 本田 耕平 石川 和夫

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.19, no.1, pp.21-24, 2007-06-01 (Released:2012-09-24)

参考文献数

13

---

Laryngeal stenosis is caused by various reasons and we are usually able to detect a cause in many cases. Occasionally we encounter a case without an obvious cause. Recently we observed such a case, and we suspected that chlorine detergent possibly caused it. The patient was a 66-year-old female whose main complaint was stridor. She had been using chlorine detergent everyday for about ten years. She had been diagnosed and treated for bronchial asthma because of the stridor. Subsequently, supraglottic stenosis was observed and it was caused by this lesion. There was no particular past history and no distinguishing pathological character in the stenosis lesion. The stenosis was removed by laryngo-fissure with a supra-hyoid approach while a surgical lumen was maintained using a core mold. She stopped using the detergent after the treatment. After sixteen months of follow-up since the operation, the patient has shown no evidence of recurrent disease.

著者

篠原 宏 清水 啓成

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.31, no.01, pp.23-27, 2019-06-01 (Released:2019-09-18)

参考文献数

8

---

It is not uncommon for otolaryngologists to encounter laryngeal edema due to infection in routine practice. However, we rarely encounter laryngeal edema caused by allergic reactions to orally ingested food.We herein report two cases of oral allergy syndrome after consumption of manuka honey candy. Both cases developed laryngeal edema and subsequent steroid administration led to the prompt improvement of symptoms. A basophil activation test for manuka honey candy was negative in both cases.

著者

那須 隆 小池 修治 倉上 和也 青柳 優

出版者

THE JAPAN LARYNGOLOGICAL ASSOCIATION

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.22, no.1, pp.8-12, 2010-06-01 (Released:2010-10-08)

参考文献数

14

---

The objective of our study was to determine the risk factors of late-onset radiation induced morphologic change and function disorder in larynx. Six cases of late-onset laryngeal necrosis and fibrosis after radiotherapy for head and neck cancers between 1994 and 2008 were evaluated. All of the patients were male with ages ranging from 57 to 74 years. The cases included three with supraglottic laryngeal cancer (T2), two with glottic laryngeal cancer (T1a), and one with an unknown origin metastatic neck tumor. Radiation injury was found from as early as 4 months up to 77 months after radiotherapy. Laryngeal late-onset radiation-induced Morphologic change and functional disorder were observed in patients having had supraglottic laryngeal cancer (T2), concurrent chemoradiotherapy, LASER surgery, or an over exposure dose. Consequently these patients were thought to be at risk for delayed radiation-induced sequelae. While almost all laryngeal necrosis was found within 6 months, supra-laryngeal fibrous stenosis was observed even beyond 24 months. It was difficult to discriminate between i Laryngeal necrosis and recurrent cancer, as well as to determine an early diagnosis of supra-laryngeal fibrous stenosis. It is, Therefore, essential that patients with risk factor of late-onset radiation-induced sequelae be followed up over the long-term.

著者

喜友名 朝則 喜瀬 乗基 真栄田 裕行 又吉 宣 比嘉 麻乃 鈴木 幹男

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.28, no.1, pp.24-30, 2016-06-01 (Released:2016-10-28)

参考文献数

38

被引用文献数

3

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A laryngeal papilloma is a benign tumor that occurs due to human papilloma virus infection. Although basically benign, the lesions often recur and grow in size. Furthermore, they sometimes show malignant transformation and often suffer from treatment. We performed a retrospective clinical analysis of 15 patients with laryngeal papilloma who were treated at our department over the past ten years. As with previous reports, most cases involved adult males and occupied the glottis. Canceration only occurred in one patient. Human papilloma virus infections were detected in 14 patients. All of the cases involved with type 6 or type 11(benign types)infections. Canceration occurred in one patient who did not show infection. The treatments performed at our center included, surgical resection and/or transpiration by a CO2 laser. Recurrence was observed in some cases. This was treated with multiple surgeries. Remission was achieved by the combination of treatment under local anesthesia and adjuvant therapy. It is difficult to cure laryngeal papilloma radically because it is a viral disease. Thus, we treat the disease as follows; we first confirm the lesion with a laryngeal endoscope under general anesthesia and perform a biopsy; and then conduct resection and/or transpiration using CO2 laser. When recurrence is observed, we immediately attempt extraction or laser transpiration under local anesthesia while the lesion is small. As the number of cases increases, it will be necessary to examine surgical method and postoperative adjuvant therapies.

著者

大津 和弥 竹内 万彦

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.22, no.1, pp.22-24, 2010-06-01 (Released:2010-10-08)

参考文献数

8

被引用文献数

1 1

---

In general, the primary therapy for mutational voice disorder has been voice therapy. However, we sometimes see cases in which voice therapy does not decrease the high pitch of mutational voice disorder. We performed an Isshiki type III thyroplasty on a patient with mutational voice disorder who had been treated by voice therapy for two years without remarkable improvement of his voice. His voice pitch became much lower after the Isshiki type III thyroplasty surgical procedure. The patient's fundamental frequency (F0) decreased from 276 Hz before surgery to 126 Hz after surgery. Isshiki type III thyroplasty was found to be useful as surgical treatment for higher pitch and resulted in a voice that was satisfactory to the patient with mutational voice disorder.

著者

讃岐 徹治 一色 信彦 中村 一博 湯本 英二

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.19, no.2, pp.54-58, 2007

被引用文献数

1

---

Thyroplasty was performed under local anesthesia on male-to-female transsexuals (MTF/GID) as well as patients with adductor spasmodic dysphonia (AdSD).<BR>There were 31 patients with MTF/GID who underwent type 4 thyroplasty during the period from 1999 to 2006. Voice fundamental frequency (F<SUB>0</SUB>) rose in all patients. Mean preoperative F<SUB>0</SUB> was 135Hz, and postoperatively the mean value was 236Hz. Type 4 thyroplasty requires specialized skill, and was found to be effective for pitch elevation surgery in MTF/GID. <BR>Forty-one patients with AdSD underwent type 2 thyroplasty with Titanium Bridge between December 2002 and December 2005. These patients were followed up 1 year postoperatively with a questionnaire. 70% of the patients judged their voice as "excellent, " and the remaining patients as improved to "good" or "fair". Type 2 thyroplasty is a highly effective therapy for AdSD.

著者

駒澤 大吾 廣崎 真柚 長谷川 智宏 渡邊 雄介

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.32, no.02, pp.129-145, 2020-12-01 (Released:2021-05-11)

参考文献数

44

---

Although it is generally accepted that phonomicrosurgery may be indicated for vocal fold mass lesions even in professional singers, the specific indications for surgery on stroboscopic findings for microlesions of the vocal folds in professional singers are not clear. The present study included 88 patients (male, n=36; female, n=52) who presented to the AKASAKA Voice Health Center with clear complaints in singing and who underwent phonomicrosurgery to resect microlesions of the vocal folds. At three months postoperatively, 102 of the total 117 subjective complaints in singing were resolved (87%). We classified five vertical locations of lesions (determined based on surgical findings) on the medial surface of the vocal folds, and statistically analyzed the differences in verticality according to the various attributes of the cases. The results showed that lesions were significantly more prevalent in the upper part of the vocal folds when the singing or disordered voice was in a high pitch and light register, while lesions were significantly more prevalent in the lower part of the vocal folds when the voice was in a low pitch and heavy register. Considering laryngeal regulation during singing, we hypothesize that lesions in the lower part of the mucosal wave-generating area are more likely to cause a malfunction in singing. A lesion in such a location can also be identified by stroboscopy, as a prominence on the medial margin in the closing phase (lesion on lower crest: LLC). Although individualized treatment is necessary, stroboscopic findings that demonstrate the presence of an irreversible LLC in singing may be a good indication for phonomicrosurgery.

著者

本橋 玲 渡嘉敷 亮二 平松 宏之 野本 剛輝 許斐 氏元 櫻井 恵梨子 豊村 文将 塚原 清彰 鈴木 衞

出版者

THE JAPAN LARYNGOLOGICAL ASSOCIATION

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.26, no.2, pp.93-98, 2014-12-01 (Released:2015-07-22)

参考文献数

11

---

Thyroarytenoid muscle myectomy (TAM) is a useful procedure for treating adductor spasmodic dysphonia (ADSD), in addition to type II thyroplasty (TP II), and both are performed in our department in Japan. In the present study, we examined the surgical outcomes of TAM. The subjects were 31 patients who underwent TAM between 2008 and 2013 at Tokyo Medical University Hospital, who could be followed up for at least six months following surgery and whose voice quality evaluation data were available. A comparison of voice evaluations pre-surgery and six months post-surgery was made. After six months, a significant improvement was seen in all of the voice quality evaluation items, including “strangulation”, “interruption”, “tremors” and voice handicap index (VHI). There was a marked recurrence of the symptoms in two of the 31 subjects within six months. Hemorrhage and scarring were observed as postoperative complications. In addition, we gave a questionnaire to 30 of the subjects who were followed up for at least one year following surgery, which asked about the recurrence of hoarseness and the degree of satisfaction with the surgery. Fifteen subjects responded (50%). The period of continuous hoarseness had ranged from one to 24 months. No subject felt that the hoarseness was a serious impediment in daily life, and the median period required for its disappearance was four months. Symptoms recurred in three subjects, but they tended to be mild. All 15 subjected reported experiencing a benefit from the surgery. The degree of satisfaction with TAM is very high, and we consider it to be a useful procedure for adductor spasmodic dysphonia.

著者

米川 紘子 安達 薫 太田 文彦

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.1, no.2, pp.139-145, 1989-12-01 (Released:2012-09-24)

参考文献数

16

被引用文献数

1

---

A total of 300 patients, 167 males and 133 females, with recurrent laryngeal nerve paralysis examined at the Department of Otolaryngology of Kinki University Hospital during the period from 1975 to 1988 were reviewed retrospectively. The results were as follows : (1) The age ranged from 40 to 79 years in 81 percent of the entire patients. (2) The incidence was higher for males than for females in the age group of 50 years and over. (3) The nerve was affected on the left in 187 (62.3%), on the right in 98 (32.7%) and on both sides in 15 patients (5.0%). (4) The paralysis was post-surgical in 125 patients and non-surgical in 175. The cause of paralysis was chest disease in 67, idiopathic in 48, neck disease (thyroid cancer in the majority) in 45, thyroid surgery in 40, chest surgery in 39 and endotracheal intubation in 36 patients. Chest diseases and surgeries were more frequent in males than in females whereas neck disease and thyroid surgeries were more frequent in females. (5) In 87 patients, paralysis resulted from malignant neoplasms. Forty-six of the 87 patients developed malignancies in the thorax. (6) The initial symptom of eight lung cancer, one mediastinal neoplasm, one esophageal cancer and three aneurysm cases was hoarseness. (7) Chest X-ray, CT and MRI and fluoroscopy of the esophagus were useful in detecting intrathoracic pathologies.

著者

片田 彰博

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.18, no.2, pp.101-106, 2006-12-01 (Released:2012-09-24)

参考文献数

15

被引用文献数

1 1

著者

金子 真美 杉山 庸一郎 平野 滋

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.32, no.01, pp.52-57, 2020-06-01 (Released:2020-09-04)

参考文献数

20

---

Medialization procedures, such as type I thyroplasty, arytenoid adduction, and vocal fold injection, are currently popular treatments for hoarseness due to unilateral vocal fold paralysis. However, hoarseness occasionally remains after medialization procedures due to tension imbalance. This tension imbalance causes diplophonia, asymmetry and aperiodic vibrational flutter in travelling wave motion. This is mostly due to incomplete glottic closure, imbalance in muscular tension, and increased air flow through an incompetent glottis. There is no established treatment for tension imbalance. We herein report two cases with remaining hoarseness post-medialization for chronic unilateral vocal fold paralysis. These patients underwent voice therapy using flow phonation to establish respiratory support and a resonant voice to facilitate vocal fold vibration. As a result, the functional vocal fold vibration, aerodynamic assessments, acoustic analysis findings and self-rated condition improved in both cases after therapy. These results suggest that voice therapy involving flow phonation and resonant voice may help improve the vocal function in cases of tension imbalance with dysphonia. Further studies with a larger number of participants or a prospective randomized controlled trial are warranted.

著者

片岡 英幸 福原 隆宏

出版者

THE JAPAN LARYNGOLOGICAL ASSOCIATION

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.26, no.2, pp.118-123, 2014-12-01 (Released:2015-07-22)

参考文献数

35

著者

竹山 勇 漆畑 保 堤 康一朗

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.5, no.1, pp.6-11, 1993-06-01 (Released:2012-09-24)

参考文献数

14

---

A marked difference in the incidence of laryngeal carcinoma between male and female has been widely unknown. The reason to this, however, has been unknown. In this connection, the affinity of the laryngeal tissue for androgen hormone was investigated in the present study. An auto radio-graphic study was conducted with the tissue of normal laryngeal mucosa and that of moderately differentiated squamous cell carcinoma of the larynx. 3H-T and its metabolites were found in the nuclei of epithelial cells of male vocal folds and some parts of male laryngeal carcinoma tissues. This suggest the existence of some effect of testosterone on the cell nuclei of these tissues. Quantitative analyses of the intracellular distribution of radioactivity conducted by means of the silver grain counting method showed that approximately 60-70% of 3H-T were located in the nuclear compartment of cancer cells of small size and the epithelium of the vocal fold near the basement membrane. The ABC method demonstrated a positive reaction in the nuclei of laryngeal carcinoma cells and the laryngeal muscle in males.These findings suggest that human laryngeal tissue, especially the vocal fold tissue, and laryngeal carcinoma cells may be one of the target organs for androgenic steroids and that androgen plays an important role in the carcinogenetic process of normal laryngeal tissue.

著者

栗田 卓 千年 俊一 佐藤 公則 坂崎 友 深堀 光緒子 末吉 慎太郎 梅野 博仁 中島 格

出版者

THE JAPAN LARYNGOLOGICAL ASSOCIATION

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.26, no.2, pp.69-74, 2014-12-01 (Released:2015-07-22)

参考文献数

13

被引用文献数

3

---

Human papilloma virus (HPV) types 6 and 11 are thought to infect the basal cells of the squamous epithelium. These infections cause laryngeal papillomatosis and condyloma acuminatum in the uterine cervix, which manifest the same pathological phenotype. The site of predilection is the junction of the stratified squamous epithelium and simple columnar epithelium (SCJ), however, the morphological characteristics of the epithelial junction in the larynx differ from that in the uterine cervix. Therefore, these observations suggest that the developmental mechanism of underlying the onset of laryngeal papilloma differs from that of condyloma acuminatum. The newborn larynx, which is infected by HPV in case of juvenile-onset laryngeal papillomatosis, has no SCJ in the supraglottic regions. This suggests that HPV infects the laryngeal epithelium with or without SCJ. Moreover, the immaturity of the epithelia in the newborn larynx allows HPV to easily infect the tissue.In investigations of adult larynges, the basal cells of the squamous epithelium and stratified ciliated epithelium in the larynx express p63, an epithelial stem cell marker. Integrin-α6 is, the receptor for HPV, is positive in the stratified ciliated epithelium and lower half of the squamous epithelium. These findings indicate that HPV is able to infect the squamous epithelium and stratified ciliated epithelium and that both infection with HPV in epithelial stem cells and stratification of epithelial cell layer are necessary for the development of laryngeal papilloma.

著者

渡嘉敷 亮二 平松 宏之

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.31, no.02, pp.129-136, 2019-12-01 (Released:2020-05-20)

参考文献数

21

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Understanding the three-dimensional (3D) movement of immobile vocal folds (VFs) is very important. Because endoscopic findings reflect only the two-dimensional movement of VFs, it is impossible to obtain a correct diagnosis. The cases presented in this article include not only those of unilateral vocal fold paralysis (UVFP) but also arytenoid dislocation, laryngeal scarring and other statuses. The main diseases are described below.UVFP : Even in cases of light UVFP, the paralyzed arytenoid is passively displaced cranially during phonation. Some surgical procedures may be applied to manage UVFP, but only arytenoid adduction can resolve this passive movement. I will also describe several specific types of UVFP, such as adductor branch paralysis (AdBP).Arytenoid dislocation (AD) : AD can be divided into two types: posterior and anterior dislocation. Our 3D computed tomography (CT) study revealed that posterior AD is very rare and often misdiagnosed as AdBP (and vice versa). We detected two subtypes of anterior AD: cranial and caudal. The VFs in cases of caudal AD are located in the mid position, and the patient’s voice is not severely affected; as such, these cases are sometimes misdiagnosed as medial UVFP.Other types of immobile VF : A number of rare and unique types of immobile VF have been reported, such as scarring after intubation or trauma, fracture, congenital and VF of many other causes. Endoscopy is insufficient for understanding what happens to a patient’s immobile VF However, 3DCT can reveal the actual status of these cases.

著者

佐藤 公則 松島 康二 一色 信彦 田辺 正博 渡邊 雄介 枝松 秀雄

出版者

THE JAPAN LARYNGOLOGICAL ASSOCIATION

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.26, no.1, pp.1-5, 2014-06-01 (Released:2014-12-17)

参考文献数

11

被引用文献数

1 2

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When Type II thyroplasty is performed, surgical management of the dihedral angle of the midline of the thyroid cartilage is very important. Clinical histoanatomy around the anterior commissure was investigated using whole organ serial sections of the human larynx to make Type II thyroplasty successful. An inner perichondrium did not exist at the dihedral angle in the upper three-forths of the midline of the thyroid cartilage. On the other hand, the inner perichondrium was present at the lower one-forth of the midline of the posterior surface of the thyroid cartilage. The attachment of the collagenous fiber (anterior commissure tendon, Broyles, 1943) extends from the upper portion of the thyroid notch caudalward for approximately upper three-forths of the midline of posterior surface of the thyroid cartilage. The midline of the posterior surface of the thyroid cartilage is only covered with thin mucosa at the laryngeal ventricle level. It is important not to perforate the mucosa when the laryngofissure is performed. In order to make the anterior commissure the proper width, it is important to split the anterior commissure tendon at the mid-line and to spread the glottis while making sure the tendons remain attached to the bilateral thyroid cartilage.

著者

岡田 亜紀 有友 宏

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.13, no.1, pp.23-26, 2001-06-01 (Released:2012-09-24)

参考文献数

16

---

Three cases of laryngeal foreign bodies in infants were treated in our hospital over the past 10 years. Among them, a case of a 1-year-old boy was reported. His chief complaint was coughing after having eaten fish. Videolaryngoscopy revealed pieces of fish bones in his subglottic space. First we removed a part of the fish bones with forceps via a flexible fiberscope following placement of a laryngeal mask under general anesthesia. Because of edema in the larynx, we removed the bones piece by piece with forceps by way of a rigid ventilation bronchoscope.With infants it is difficult to diagnose a laryngeal foreign body especially in the subglottic space. Videolaryngoscopy is useful in such cases. Before removal of a laryngeal foreign body, careful observation is mandatory to avoid unnecessary damage to the trachea and the larynx. To inspect the larynx and the trachea, the flexible fiberscope is a choice instrument following placement of a laryngeal mask under general anesthesia.

著者

西山 耕一郎

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.28, no.2, pp.93-100, 2016-12-01 (Released:2017-06-13)

参考文献数

22

被引用文献数

1

---

Dysphagia has now become a common disease in Japan, and the presence of otolaryngologists is more significant in the dysphagia clinics. Impaired swallowing function can easily cause suffocation and aspiration pneumonia which can be induced by food, saliva and stomach acid. Patients with dementia could have a suffocation by filling up food in their mouth. Although the aspiration pneumonia in elderly patients is difficult to avoid, an oral diet can often be continued with appropriate treatment. Multidisciplinary team approach is necessary in the field of swallowing medicine, however the otolaryngologist can play a leading role in the team evaluating the swallowing function and treating the dysphagia and pneumonia.

著者

宮本 真 楠山 敏行 森 有子 中川 秀樹 田村 悦代 新美 成二 福田 宏之

出版者

THE JAPAN LARYNGOLOGICAL ASSOCIATION

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.21, no.2, pp.117-122, 2009-12-01 (Released:2014-12-26)

参考文献数

5

---

Vocal fold scarring due to injury, inflammation or surgery results in stiffness of the layer structure of the vocal fold. In addition, the mucosal waves are singnificantly affected, thereby resulting in severe dysphonia. Many therapeutic strategies have been attempted for the treatment of vocal fold scarring including voice therapy, steroid injection, injection laryngoplasty, tissue engineering and regenerative medicine. Our surgical method involves the removal of the vocal fold scarring under laryngomicrosurgery. From 2001 to 2007, we performed our phonosurgery technique on 18 patients with vocal fold scarring. The 15 patients whom were observed over two months (6 men and 9 women) ranged in age from 19 to 67 years (average age, 42.9 years). Our observations involved evaluation of subjective symptoms, as well as stroboscopic and phonometer examinations. The operation is performed under the general anesthesia. The approach is to resect the vocal fold nodule-like scarring and to resect vocal fold scarring under the mucosal epithelium. Twelve of the 18 patients had satisfactory post-surgery traveling waves and phonation. Definitive strategies in the treatment of vocal fold scarring have yet to be established. Our surgical method to treat scar formation is to remove the scar tissue under the mucosa. The key point is that we strive to attain the most excellent wound healing in order to achieve the closest reproduction of a normal vocal fold structure.

著者

岩田 重信 岩田 義弘 大山 俊廣 門山 浩 斎藤 正治 高須 昭彦

出版者

日本喉頭科学会

雑誌

喉頭 (ISSN:09156127)

巻号頁・発行日

vol.10, no.1, pp.1-7, 1998-06-01 (Released:2012-09-24)

参考文献数

18

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The electroglottogram (EGG) has been used to obtain details of vocal fold vibration. Applications of the EGG, however, are limited in use for voice disorders since characteristics of EGG waveforms associated with vocal fold vibrations are still poorly understood. We analysed the EGG waveform characteristics to compare them with simultaneous measurements of supra and subglottic pressure in the normal male subject sustaining the vowel /a/ at constant pitch with different intensity levels. The results are : The periodicities of the consequent frequency are completely coincident among the EGG wave, supra and subglottic pressure waveforms at different intensity levels. With regard to the amplitude variations of the EGG waveform in the vocal cycle, the increasing amplitude corresponded with a rapid increase of subglottic pressure and a decrease of supraglottic pressure which is indicative of the closing phase of the vocal folds. The gradual fall of amplitude associated with the parting of the vocal folds corresponded with an increase of supraglottic pressure from negative values and maintenance of negative subglottic pressure. The negative flatter portion of EGG wave corresponding to the opened phase exhibited higher positive supra glottal pressure and lower pressure of the subglottic even at different sound pressure levels. When increasing the intensity during constant pitch phonation, the values of the contact quotient and contact speed index decreased, and the contact closing slope became steeper.These findings reveal the tendency of increasing vocal tension following louder vocalization. Simultaneous measurement of EGG waveforms, and supraglottic and subglottic pressures might provide useful and detailed information for understanding EGG waveforms, laryngeal dysfunction and/or research for voice disorders.