Analysis of magnetic resonance imaging in paranasal mucocele with visual disturbance.

Introduction Ocular imaging strategies have evolved to facilitate the diagnosis of optic neuropathy. This study aimed to evaluate the pathogenesis of visual disturbance associated with paranasal mucocele via magnetic resonance imaging (MRI). Methods A total of 19 patients with mucocele and visual disturbance who underwent endoscopic sinus surgery, orbital MRI, and sinus computed tomography were included. The age, sex, days from onset to surgery, eye pain, and imaging findings were analyzed. The results were compared between two groups: 7 patients with preoperative visual acuity worse than 20/200 (the poor group) and 12 patients with equal or better than 20/200 (the fair group). Results Imaging showed a high compression rate of the orbit in 17 (89.5%) and enlargement of the subarachnoid space around the optic nerve in 15 (78.9%) of 19 patients. Preoperative vision was significantly poor in cases with hyperintense regions in the optic nerve on T2-weighted imaging, indicating the presence of optic neuritis. No cases showed severe inflammation of the cyst or the presence of intraorbital fat tissue. Conclusion MRI-based diagnosis proved useful in evaluating pathological factors, such as orbital compression, ischemia, and optic neuritis, in individual cases. It can help gain insight into the pathogenesis of and developing appropriate treatment strategies for visual disturbances associated with paranasal mucocele.

Swallowing-related muscle inflammation and fibrosis induced by a single dose of radiation exposure in mice.

BACKGROUND: Although radiotherapy is commonly used to treat head and neck cancer, it may lead to radiation-associated dysphagia (RAD). There are various causes of RAD, however, the mechanism has not yet been fully identified. Currently, the only effective treatment for RAD is rehabilitation. Additionally, there are few available animal models of RAD, necessitating the development of new models to establish and evaluate RAD treatments. We hypothesize that radiation-induced neck muscle fibrosis could be one of the causes of RAD due to impairment of laryngeal elevation. Therefore, in this study, we focused on the changes in inflammation and fibrosis of the strap muscles (Sternohyoid, Sternothyroid, and Thyrohyoid muscles) after a single-dose irradiation. This research aims to provide a reference animal model for future studies on RAD. RESULTS: Compared to control mice, those treated with 72-Gy, but not 24-Gy, irradiation had significantly increased tumor necrosis factor-α (TNF-α) (p < 0.01) and α-smooth muscle actin (αSMA) (p < 0.05) expression at 10 days and significantly increased expression levels of motif chemokine ligand-2 (CCL2), α-SMA, tumor growth factor-ß1 (TGF-ß1), type1 collagen, and interleukin-1ß (IL-1ß) (p < 0.05) in the muscles at 1 month by real-time PCR analysis. The results of immunohistochemistry showed that the deposition of type 1 collagen gradually increased in extracellular space after radiation exposure, and the positive area was significantly increased at 3 months compared to non-irradiated control. CONCLUSIONS: A single dose of 72-Gy irradiation induced significant inflammation and fibrosis in the strap muscles of mice at 1 month, with immunohistochemical changes becoming evident at 3 months. This cervical irradiation-induced fibrosis model holds potential for establishing an animal model for RAD in future studies. LEVEL OF EVIDENCE: N/A.

Questionnaire Survey to Identify the Medical Departments That Patients With Possible Head and Neck Cancer (HNC) Symptoms Tend to Choose.

In the treatment of head and neck cancer (HNC), any delay in omit initiation worsens the overall prognosis. Thus, the early start of HNC treatment is crucial. Unfortunately, treatment delays persist in clinical practice. There are several possible reasons for this. One reason is that patients with HNC do not visit an ear, nose, and throat (ENT) doctor. This is because non-ENT doctors (e.g., general practitioners {GPs}) lack expertise in HNC and therefore may unrecognize it. Therefore, guiding patients with suspected HNC symptoms to an otorhinolaryngologist, an HNC specialist, is necessary. To determine the departments that patients with potential HNC symptoms tend to select, we administered a questionnaire survey to 140 participants. Fewer than 60% of respondents indicated they would consult an otorhinolaryngologist even when recognizing symptoms suggestive of HNC. Notably, a significantly low percentage of respondents mentioned they would consult an otorhinolaryngologist for neck masses. Public awareness of HNC symptoms, especially the association between a neck mass and HNC, is limited. The lack of understanding by the general public regarding the relationship between neck masses and HNC is a challenge to prompt initiation of treatment.

Proto-oncogene mutations in middle ear cholesteatoma contribute to its pathogenesis.

BACKGROUND: Chronic inflammation causes bone destruction in middle ear cholesteatomas (MECs). However, the causes of their neoplastic features remain unknown. The present study demonstrated for the first time that neoplastic features of MEC are based on proto-oncogene mutations. RESULTS: DNA was extracted from MEC and blood samples of five patients to detect somatic mutations using depth-depth exome sequencing. Exons with somatic variants were analyzed using an additional 17 MEC/blood test pairs. Variants detected in MECs but not in blood were considered pathogenic variant candidates. We analyzed the correlation between proto-oncogene (NOTCH1 and MYC) variants and the presence of bone destruction and granulation tissue formation. MYC and NOTCH1 variants were detected in two and five of the 22 samples, respectively. Two of the NOTCH1 variants were located in its specific functional domain, one was truncating and the other was a splice donor site variant. Mutations of the two genes in attic cholesteatomas (n = 14) were significantly related with bone destruction (p = 0.0148) but not with granulation tissue formation (p = 0.399). CONCLUSIONS: This is the first study to demonstrate a relationship between neoplastic features of MEC and proto-oncogene mutations.

Impact of low pharyngeal/esophageal pressure associated with sarcopenia on postendoscopic submucosal dissection pneumonia in patients with superficial esophageal cancer.

OBJECTIVES: The aging population, including patients with superficial esophageal cancer, encounters critical dysphagia- and postoperative pneumonia-related issues. Although endoscopic submucosal dissection (ESD) provides advantages over other modalities, older patients are at higher risk of postoperative pneumonia. Furthermore, the etiologies of pneumonia are complex and include patient- (such as sarcopenia) and treatment- (including ESD) related factors. Therefore, this study evaluated swallowing function in patients with superficial esophageal cancer and identified post-ESD pneumonia-associated factors. METHODS: Comprehensive swallowing function and sarcopenia were evaluated in patients pre-ESD and 2 months post-ESD using high-resolution manometry and several swallowing studies by multiple experts. The effects of mucosal resection and sarcopenia on swallowing function changes post-ESD, the relationship between preoperative swallowing function and sarcopenia, and the factors influencing postoperative pneumonia were investigated. RESULTS: Twenty patients were included in the study. Patients with preoperative sarcopenia had significantly lower pharyngeal/upper esophageal sphincter and tongue pressures than those without sarcopenia. However, ESD did not worsen pharyngeal or upper esophageal pressure. Post-ESD pneumonia incidence tended to be higher in patients with sarcopenia than in those without sarcopenia. The lower upper esophageal sphincter-integrated relaxation pressure (UES-IRP) was a significant factor in pneumonia development. Furthermore, the receiver operating characteristic curve for UES-IRP in pneumonia yielded an area under the curve of 0.82. CONCLUSIONS: Sarcopenia is associated with preoperative dysphagia, which increases post-ESD pneumonia risk. Therefore, postoperative pneumonia incidence is expected to increase with an aging population, making preoperative sarcopenia and swallowing function evaluation crucial.

Three Signs to Help Detect Sjögren's Syndrome: Incidental Findings on Magnetic Resonance Imaging and Computed Tomography.

This study aimed to retrospectively investigate the prevalence of Sjögren's syndrome (SS) among patients with ranulas, parotid cysts, or parotid calcifications; identify the characteristic magnetic resonance imaging (MRI) or computed tomography (CT) findings of the lesions associated with SS; and compare the SS disease stages among SS patients with the three lesion types. A total of 228 patients with the lesions were classified into SS, possible SS, and non-SS groups. The prevalence of SS among patients with ranulas, parotid cysts, or parotid calcifications was 16%, 24%, and 40%, and the rates of either SS or possible SS were 25%, 41%, and 64%, respectively. SS was associated with (i) ranulas: ≤17 mm; (ii) parotid cysts: bilateral and multiple; and (iii) parotid calcifications: in females, bilateral, multiple, parenchymal, and no coexisting calcifications in other tissues. SS patients with ranulas were significantly younger and had lower submandibular gland stage scores on MRI/CT than those with other lesions. Additionally, in 58% and 15% of SS patients with ranulas and parotid calcifications, respectively, detection of the lesions led to the diagnosis of primary SS. Therefore, recognizing the prevalence of SS among patients with these lesions and the findings associated with SS can help detect undiagnosed SS.

Long-term speech perception performance in prelingually deafened adult cochlear implant recipients.

To investigate the postoperative long-term outcomes after an average of 9.2 years following cochlear implantation (CI) in prelingually deafened adults, along with preimplantation factors predicting postoperative outcomes.Twenty-six prelingually deafened adults who underwent CI at >18 years were compared with those who had undergone CI in childhood (<9 years) and were >10 years old. Outcome measures includedhearing thresholds, preoperative and postoperative aided hearing level (HL), speech discrimination score (SDS), and Categories of Auditory Performance (CAP) scores. Correlation analyses were performed on the following: SDS results, aided HL, school attendant status, implant manufacturers, and speech processor models.Improvement was achieved in the aided HL and SDS results, although these results were not better than those of the child group. CAP score was also statistically significantly improved after CI. Statistically significant correlation between the preoperative SDS and postoperative HL with CI results was observed. In other words, the better the preoperative SDS results, the better the postoperative SDS results.Prelingually deafened adults achieved considerable improvement through CI. It is important to understand that patients achieving better hearing with a well-fitted hearing aid and good SDS performance before surgery may be good candidates for CI.

Bilateral Rhinogenous Optic Neuropathy Caused by the Regrowth of a Large Sphenoid Sinus Mucocele.

A 59-year-old man, who had a history of left blind at 36 years old, suddenly lost right visual acuity. Magnetic resonance imaging revealed a large left sphenoid sinus cyst, which protruded intracranially. The cyst was fenestrated by endoscopic sinus surgery, but his right vision did not recover. Ten cases of bilateral rhinogenous optic neuropathy caused by mucocele have been reported, and the cause was sphenoid sinus in 9 cases. Postoperative visual acuity in these cases was poor, especially in slow progressive cases, because it was diagnosed as an unknown cause, and surgery was delayed. Rhinogenous optic neuropathy caused by mucocele should be differentiated from bilateral visual impairment of unknown cause. The authors highlight the importance of early diagnosis of sphenoid sinus mucocele and fully informing patients about the future risk of bilateral visual impairment, even if they are asymptomatic or have been treated.

Sphenoid sinus schwannoma with adhesion to the carotid canal.

Few reports have been made on the presentation and treatment of schwannomas originating in the sphenoid sinus due to their rarity. We report the case of a 60-year-old woman who presented with a cyst-like mass in the right sphenoid sinus on magnetic resonance imaging. Computed tomography showed a bone defect in the internal carotid artery (ICA) and enlargement of the round foramen on the affected side. A histopathological diagnosis of schwannoma was made, and endoscopic sinus surgery was performed. The anterior part of the tumor could be easily removed by aspiration; however, its adhesion to the ICA was remarkable, and its boundaries were unclear. Although partial paralysis of the maxillary nerve remained, no recurrence occurred for over 10 years. Careful evaluation should be performed to check for bone defects in the nerve to differentially diagnose schwannoma from cystic masses of the sphenoid sinus. Additionally, excision of masses similar to the presented case may expectedly be difficult because of unclear excisional margins and strong capsule adherence to important organs such as the ICA. Moreover, correct imaging, histopathological diagnosis, and appropriate informed consent are essential before surgery.

CT analysis of predictors for visual acuity in optic neuropathy with mucocele.

OBJECTIVE: To evaluate the causative and risk factors for optic neuropathy with mucocele via imaging studies. METHODS: We included 21 patients with rhinogenous optic neuropathy with mucocele. We collected data on the sinus involved, age, sex, number of days from the onset of visual impairment to surgery, and computed tomography (CT) imaging findings (bone defects in the lamina papyracea, Onodi cell mucocele, exophthalmos, and optic nerve deviation). The results were compared between two groups, the one having nine patients with pre-operative visual acuity of <0.1 (the poor group) and the other having 12 patients with pre-operative visual acuity of ≥0.1 (the fair group). Whether or not there was a difference in pre-operative visual acuity between patients with and without Onodi cell mucocele was determined. RESULTS: After surgery, visual acuity improved in 16/21 (76.2%) patients, and a correlation analysis showed a significant positive correlation between pre-operative and post-operative visual acuity. In imaging, the causative sinuses accounted for 85.7% of both posterior ethmoid and sphenoid sinuses. Bone defects of the lamina papyracea at the optic canal and the vertical downward deviation of the optic nerve at each location, especially in 6/9 patients with Onodi cell mucocele, were characteristic in the poor group. In these conditions, increasing the contact areas of the optic nerve and mucocele can leads to more chances of direct downward compression of the optic nerve and infection occurring, and it may lead to severe pre-operative visual impairment. CONCLUSION: Imaging studies of optic neuropathy with mucocele help to determine the risk factors and perform early and precise diagnostic imaging and decision-making for surgery.

Factors Affecting the Swallowing Dysfunction Following Oral Cancer Surgery.

OBJECTIVE: To investigate the factors affecting the postoperative swallowing dysfunction in patients who underwent oral cancer surgery. METHODS: Retrospective review of clinical records of 70 patients (50 males and 20 females) who underwent oral cancer surgeries from July 2007 to April 2015 were enrolled. Multiple regression analysis was performed using the Food Intake LEVEL Scale (FILS) at discharge as the objective variable and age, tumor size, resection of the tongue base, suprahyoid muscle resection, segmental mandibulectomy, neck dissection and radiation therapy as the explanatory variables in 70 patients. In addition, multiple regression analysis was performed between objective variables, which include maximum hyoid bone movement, laryngeal elevation delay time, pharyngeal constriction ratio (PCR), residue in the vallecular and pear-shaped depression (pyriform sinuses), and Penetration-Aspiration Scale score and one of the main factors representing the characteristics of each case as the explanatory variables, and age was treated as an adjustment factor in 23 patients. RESULTS: The FILS shows significant negative correlation by age and resection of the tongue base. In videofluoroscopic swallowing study, the maximum movement, PCR and residue in the vallecular are significantly correlated with factors demonstrating the characteristic for each case. CONCLUSION: It was suggested that in elderly patients, the presence of more than half of the tongue base resection, suprahyoid muscle resection and neck dissection cause severe dysphagia after surgery.

Swallowing dysfunction in myasthenia gravis patients examined with high-resolution manometry.

OBJECTIVE: To prospectively compare oropharyngeal swallowing dysfunction in myasthenia gravis (MG) patients presenting with difficulty in swallowing between the neutral and chin-down positions, based on the results of high-resolution manometry (HRM) examination. METHODS: We prospectively compared the HRM results of swallowing studies of seven MG patients showing difficulty in swallowing (neutral and chin-down positions) at the Department of Neurology of our institution during the period February-December 2018. The HRM assessment parameters were as follows: maximum swallowing pressure (SP) at the soft palate, meso­hypopharynx, and upper esophageal sphincter (UES), and the duration of relaxation pressure at the UES. These parameters were compared between the two positions and their correlations with the results of neurological evaluations, such as the Quantitative Myasthenia Gravis (QMG) score (total and neck muscles alone), and grip strength, were also analyzed. RESULTS: In comparison with the neutral position, in the chin-down position the maximum SP at the meso­hypopharynx was significantly increased (p < 0.05), the maximum SP at the UES was significantly decreased (p < 0.05), and the duration of relaxing SP at the UES was significantly increased (p < 0.05). Interestingly, there were no correlations between the SP at any location and the results of the neurological evaluations. CONCLUSIONS: The chin-down position appears useful for improving pharyngeal clearance in MG patients, by promoting increased SP at the meso­hypopharynx, relaxing SP at the UES, and increasing the duration of relaxation pressure at the UES.

Different types of dysphagia alleviated by the chin-down position.

OBJECTIVE: Retrospective videofluoroscopic swallowing study (VFSS) evaluations of pharyngeal swallowing were used to evaluate the types of dysphagia alleviated by the chin-down maneuver. MATERIALS AND METHODS: The study population consisted of 64 patients who underwent VFSS evaluations during neutral and chin-down maneuvers presenting specifically penetration or aspiration. The assessment of the VFSS movie clips of each maneuver was performed using parameters of the Modified Barium Swallow Impairment Profile (MBSImP) and the presence and degree of airway invasion(PDAI) by three blinded raters in the following five subcategorized groups, 1. patietns presenting penetration or aspiration during swallow 2. after swallow, patients of 3. head and neck, 4. digestive and 5. neuromuscular disorders, respectively. The scores registered for the two maneuvers were statistically compared. Additionally, we examined statistically which factors had the impact on the improvement of the PDAI using fisher's exact test. RESULTS: Compared with the neutral position, PDAI, pharyngeal constriction, anterior hyoid movement, pharyngeal constriction, laryngeal elevation, laryngeal closure, upper esophageal sphincter opening, initiation of the pharyngeal swallow, and pharyngeal clearance in pyriform sinus were significantly (p < 0.01-0.05) improved with the chin-down maneuver. In a subcategory comparison with group 1, 3 and 4, the PDAI improved significantly (p < 0.01) with the chin-down maneuver, in which laryngeal elevation and laryngeal closure had statistically the impact (p < 0.01-0.05) on improvement of PDAI. CONCLUSION: The chin-down maneuver was most effective in improving swallow function when the impairment included penetration and aspiration during swallow caused by inadequate laryngeal elevation and laryngeal closure.

Brothers with novel compound heterozygous mutations in COL27A1 causing dental and genital abnormalities.

COL27A1 encodes a collagen type XXVII alpha 1 chain. It is the product of this gene that provides the structural support of connective tissue and is reported to be the causative gene of Steel syndrome (OMIM #615155). The primary symptoms of patients with this defect are consistent with systemic bone disease; however, recent reports note findings of intellectual disability and hearing loss. In this study, we identified novel COL27A1 compound heterozygous variants in two brothers with rhizomelia and congenital hip dislocation as well as dental and genital abnormalities that have not yet been reported in Steel syndrome. This variant, of maternal origin, caused an amino acid substitution of arginine for glycine, c.2026G>C or p.G676R, in the collagen helix domain, which is assumed to damage the structure of the helix. The paternally transmitted variant, c.2367G>A, is located at the 3' end of exon 12, and cDNA analysis revealed a splicing alteration. These novel, compound heterozygous COL27A1 variants might indicate an association of the gene with tooth and genital abnormalities.

Swallowing dysfunction following surgery for well-differentiated thyroid cancer with extrathyroid invasion.

BACKGROUND: Differentiated thyroid carcinoma (DTC) can invade the surrounding aerodigestive tract. Radical surgery for locally advanced DTC will require resection of the trachea, recurrent laryngeal nerve (RLN), inferior pharyngeal constrictor muscles (IPCMs), or a part of the esophagus. The purpose of this study was to demonstrate the effect of resection of these surrounding tissues combined with total thyroidectomy and neck dissection on swallowing function following surgery. METHODS: We performed total thyroidectomy combined with neck dissection and resection of the RLN in 24 patients with DTC with extrathyroidal invasion (19 unilateral, 1 bilateral), IPCMs (n = 5), or muscle layers of esophagus (n = 9). Nine patients received a tracheostomy placement due to a window resection of the trachea for tumor invasion (n = 6) and necessary upper airway management (n = 3). We used the duration of nasogastric tube feeding to evaluate swallowing function following surgery. RESULTS: Patients who underwent tracheostomy or IPCM resection showed significantly longer periods of tube feeding (p = 0.0057 and 0.0017, respectively). In contrast, resection of the unilateral RLN or esophageal muscle layer showed no difference in tube feeding duration. Multiple regression analysis indicated that tracheostomy and IPCM resection were significant independent predictors of longer periods of tube feeding (p = 0.04583 and 0.00087, respectively). CONCLUSION: These results indicate that tracheostomy placement and resection of the IPCMs, together with total thyroidectomy, extends the tube feeding duration in the postoperative period.

The effect of a chin-down maneuver after esophagectomy on oropharyngeal swallowing pressure measured using high-resolution manometry.

OBJECTIVE: To elucidate the effects of a chin-down maneuver using high-resolution manometry (HRM) to measure pharyngeal swallowing pressure (SP) after esophagectomy. METHODS: We evaluated 9 of 16 patients who underwent esophagectomy featuring gastric tube reconstruction and three-field lymph node dissection (3FL) in our Department of Gastroenterological Surgery from September 2015 to June 2016. We compared all parameters of the neutral and chin-down positions using HRM to measure the maximum SP at the velopharynx, meso-hypopharynx, and upper esophageal sphincter (UES) and the duration of lowered SP at the UES, the distance from nostrils to the boundary between hypopharynx and UES and to derive SP and SP propagation curves at various distances from the nostrils. RESULTS: Compared to that at the neutral position, the maximum SP at the velopharynx was significantly lower in the chin-down position (p<0.05); however, SP at the meso-hypopharynx and UES did not differ significantly. The duration of lowered SP at the UES was significantly prolonged in the chin-down position and the distance from nostrils to the boundary between hypopharynx and UES was significantly shortened representing the elevation of the larynx, respectively (p<0.05, p<0.01). On the SP propagation curve for males, the times to SP peaks at 13, 16, 17, and 18cm from the nostrils were significantly prolonged (all p<0.05) in the chin-down position. CONCLUSION: Chin-down positioning after esophagectomy/3FL may improve bolus passage by prolonging the duration of lowered SP at the UES, possibly by enhancing laryngeal elevation.

Detection of hypopharyngeal cancer (Tis, T1 and T2) by ENT physicians vs gastrointestinal endoscopists.

OBJECTIVES: Hypopharyngeal cancer is typically detected at a late stage by ear, nose, and throat (ENT) physicians, when the prognosis is poor. We evaluated how hypopharyngeal cancer (Tis, T1 and T2) were detected by ENT physicians and gastrointestinal endoscopists (GEs) according to the detection reasons. MATERIALS AND METHODS: A total of 109 consecutive patients with hypopharyngeal cancer (Tis, T1 and T2) who received treatment in our institution from January 2014 to February 2018 was enrolled. The detection detail of hypopharyngeal cancer lesions by ENT physicians and GEs, tumor size and location, and the characteristics of the lesions missed by ENT physicians and GEs were reviewed retrospectively. RESULTS: Twenty seven and 82 of 109 (24.8% and 75.2%) patients were detected by ENT physicians and GEs, respectively. The most frequent original reasons for ENT physicians and GEs were both pharyngeal discomfort screening and examination of swollen neck lymph nodes (12 of 27, 44.4% for each) and pre-treatment or follow-up screening for esophageal cancer (25 of 82, 30.5%), respectively. Among the 13 cases of upper gastrointestinal tract screening of the head-and-neck cancer other than pharyngeal cancer detected by GEs, 11 (84.6%) were missed by ENT physicians. In contrast, among the 25 cases of pre-treatment screening of the esophageal cancer detected by GEs, 12 (48%) were missed by other GEs just before the consultation from other institutions. CONCLUSIONS: The percentage of detection of hypopharyngeal cancer (especially, Tis and T1) by ENT physicians is low. A careful examination of the pharynx should be conducted by GEs.

Phonatory function in patients with well-differentiated thyroid carcinoma following meticulous resection of tumors adhering to the recurrent laryngeal nerve.

BACKGROUND: Well-differentiated thyroid carcinomas (WDTCs) sometimes adhere firmly to the recurrent laryngeal nerve (RLN), while allowing normal mobility of the vocal fold (VF). Meticulous dissection of the adhered tumor from the RLN is known to be effective, preserving VF mobility and oncological safety. However, phonatory function following this preservation procedure has yet to be evaluated sufficiently. The objective of this study was to examine phonatory function following the preservation procedure. METHODS: Ten patients with WDTCs, demonstrating normal preoperative VF mobility with tumors adhering to the RLN, underwent the preservation procedure between 2000 and 2013 (preservation group). During the same period, nine patients with WDTCs demonstrating normal VF mobility underwent resection and reconstruction of the tumor-invaded RLNs (reconstruction group). Phonatory function, including maximum phonation time (MPT), mean flow rate (MFR), jitter, shimmer, harmonics-to-noise ratio, and GRBAS scale score, was evaluated and compared statistically between the two groups. RESULTS: The mean values of MPT and MFR in the preservation group were at normal levels. Both G and B scores of GRBAS scale were at near-normal levels. Additionally, the mean B score of the GRBAS scale was significantly better in the preservation group than in the reconstruction group. CONCLUSIONS: When normal VF mobility is observed preoperatively, meticulous resection for preserving RLN would contribute to maintain not only normal level of MPT and MFR, but also to provide better B score of GRBAS scale than RLN resection followed by immediate reconstruction.

Pathophysiology of Fibrosis in the Vocal Fold: Current Research, Future Treatment Strategies, and Obstacles to Restoring Vocal Fold Pliability.

Communication by voice depends on symmetrical vibrations within the vocal folds (VFs) and is indispensable for various occupations. VF scarring is one of the main reasons for permanent dysphonia and results from injury to the unique layered structure of the VFs. The increased collagen and decreased hyaluronic acid within VF scars lead to a loss of pliability of the VFs and significantly decreases their capacity to vibrate. As there is currently no definitive treatment for VF scarring, regenerative medicine and tissue engineering have become increasingly important research areas within otolaryngology. Several recent reviews have described the problem of VF scarring and various possible solutions, including tissue engineered cells and tissues, biomaterial implants, stem cells, growth factors, anti-inflammatory cytokines antifibrotic agents. Despite considerable research progress, these technical advances have not been established as routine clinical procedures. This review focuses on emerging techniques for restoring VF pliability using various approaches. We discuss our studies on interactions among adipose-derived stem/stromal cells, antifibrotic agents, and VF fibroblasts using an in vitro model. We also identify some obstacles to advances in research.