Intracordal Injection Research Articles

Acute Effects of Steroids on Vocal Fold Epithelium Post-injury in a Preclinical Model.

Glucocorticoids (GCs) are commonly prescribed for laryngeal indications due to their potent anti-inflammatory properties. However, GCs effect on vocal fold (VF) epithelial morphology and barrier function following injury is overlooked and may be key to efficacy. In this study, the effects of GCs on epithelial morphology and barrier function were quantified in injured VFs. We seek to increase our understanding of biochemical processes underlying GC mechanisms to refine therapeutic strategies. Microflap injury was induced in 65 rabbits. Seven days after injury, animals received bilateral 20 μL intracordal injections of saline, dexamethasone, methylprednisolone, or triamcinolone (n = 15 per condition). Five rabbits in each condition were euthanized 1, 7, or 60 days following treatment. An additional five animals served as non-injured/untreated controls. To quantify transepithelial electrical resistance (TEER), 1 mm epithelial biopsies were placed in an Ussing chamber. The contralateral VF was processed for transmission electron microscopy and epithelial depth analysis. At 60 days, GC treatment maintained TEER levels similar to non-injured/untreated controls. However, triamcinolone reduced TEER compared with saline-treated conditions. Acutely, epithelial hyperplasia typically persisted in all injured VFs. At 60 days, only dexamethasone and triamcinolone increased epithelial depth in injured VFs; all GCs increased epithelial depth compared with non-injured/untreated controls. Acutely, GCs did not alter TEER. Additionally, GCs did not alter epithelial depth compared with saline treatment, indicating alignment with natural healing responses. At 60 days, GCs exhibited varying degrees of TEER restoration and epithelial hyperplasia, possibly due to distinct pharmacodynamic profiles. NA Laryngoscope, 2024.

Changes in vital signs during adrenaline administration for hemostasis in intracordal injection: an observational study with a hypothetical design of endotracheal adrenaline administration in cardiopulmonary arrest

BackgroundThe background is that intravenous adrenaline administration is recommended for advanced cardiovascular life support in adults and endotracheal administration is given low priority. The reason is that the optimal dose of adrenaline in endotracheal administration is unknown, and it is ethically difficult to design studies of endotracheal adrenaline administration with non-cardiopulmonary arrest. We otolaryngologists think so because we administered adrenaline to the vocal folds for hemostasis after intracordal injection under local anesthesia, but have had few cases of vital changes. We hypothesized that examining vital signs before and after adrenaline administration for hemostasis would help determine the optimal dose of endotracheal adrenaline.MethodsWe retrospectively examined the medical records of 79 patients who visited our hospital from January 2018 to December 2020 and received adrenaline in the vocal folds and trachea for hemostasis by intracordal injection under local anesthesia to investigate changes in heart rate and systolic blood pressure before and after the injection.ResultsThe mean heart rates before and after injection were 83.96 ± 18.51 (standard deviation) beats per minute (bpm) and 81.50 ± 15.38 (standard deviation) bpm, respectively. The mean systolic blood pressure before and after the injection were 138.13 ± 25.33 (standard deviation) mmHg and 135.72 ± 22.19 (standard deviation) mmHg, respectively. Heart rate and systolic blood pressure had P-values of 0.136, and 0.450, respectively, indicating no significant differences.ConclusionsAlthough this study was an observational, changes in vital signs were investigated assuming endotracheal adrenaline administration. The current recommended dose of adrenaline in endotracheal administration with cardiopulmonary arrest may not be effective. In some cases of cardiopulmonary arrest, intravenous and intraosseous routes of adrenaline administration may be difficult and the opportunity for resuscitation may be missed. Therefore, it is desirable to have many options for adrenaline administration. Therefore, if the optimal dose and efficacy of endotracheal adrenaline administration can be clarified, early adrenaline administration will be possible, which will improve return of spontaneous circulation (ROSC) and survival discharge rates.

Evaluation of Safety After Intracordal Basic Fibroblast Growth Factor Injection

Although there are many reports of voice improvement with intracordal trafermin (a basic fibroblast growth factor) injections under local anesthesia, few papers have documented the safety of trafermin. Therefore, we aimed to investigate whether trafermin is safer than control drugs (triamcinolone acetonide) early after intracordal injection under local anesthesia. We conducted a retrospective review from the medical records of patients who underwent intracordal injection with trafermin and triamcinolone acetonide under local anesthesia at our institution. Early postinjective complications were defined as changes in vital signs and chief complaints early after intracordal injection. A total of 699 and 297 patients underwent intracordal injection under local anesthesia with trafermin and triamcinolone acetonide, respectively. Of these, 227 and 130 patients had early postinjective complications with trafermin and triamcinolone acetonide, retrospectively. The most common complications occurring with trafermin was increased blood pressure in 39 cases (5.58%): 17 cases (2.43%) of blood pressure increase of ≥20 mm Hg. Other complications included pharyngeal discomfort in 37 (5.29%), lightheadedness in 33 (4.72%), and phlegm discharge in 29 (4.15%). Triamcinolone acetonide caused pharyngeal discomfort in 28 patients (9.43%), phlegm discharge in 17 patients (5.72%), lightheadedness in 12 patients (4.04%), sore throat in 11 patients (3.70%), increased blood pressure in 10 patients (3.37%): 7 cases (2.36%) of blood pressure increase of ≥20 mm Hg, and dizziness in seven patients (2.36%). Statistical analysis of the complications between trafermin and triamcinolone acetonide showed no significant differences. The proportion of early postinjective complications from intracordal injection of trafermin is no significant difference in that of triamcinolone acetonide. The results suggest that the early postinjective complications are not due to the drug action of trafermin, but rather to complications from the intracordal injection procedures. Intracordal trafermin injection may be safe in the short term.

Changes in serum basic fibroblast growth factor concentration following intracordal injection.

Although many studies have reported improvements in voice outcomes with intracordal trafermin injection, there is a lack of data documenting its changes in serum basic fibroblast growth factor (bFGF) blood concentration. This study examined whether serum bFGF concentrations change after intracordal trafermin injection. This retrospective study was conducted at Tokyo Voice Center. We investigated serum bFGF concentrations before and after injection in 40 patients who underwent intracordal trafermin injection. There were 26 males and 14 females, with an age ranging from 13 to 88 years (average 53.25 years). They were diagnosed with paralysis (15 patients), atrophy (15 patients), sulcus (8 patients), and others (2 patients: scar and functional), presenting with severe hoarseness that interfered with daily life. The mean pre- and post-injective serum bFGF concentration of the 40 patients was 6.689 and 4.658 pg/mL, respectively. The difference in mean serum bFGF concentration between pre- and post-injective was -2.031 pg/mL. The Pearson correlation coefficient was calculated to evaluate the correlation between dosage of trafermin and post-injective serum bFGF concentration, and a moderate correlation was found at r = 0.52. Generalized linear model regression analysis was performed for the purpose of adjusting for confounding among variables. The only variable that showed a statistically predominant association with post-injective serum bFGF concentrations was the dosage of trafermin, with an estimated regression coefficient of 0.048. In this study, the dosage of trafermin we injected and post-injective serum bFGF concentrations were dose-dependent but the amount of changes in the serum bFGF concentration was negligible within the physiological range. Therefore, as with subcutaneous and wound administration, intracordal trafermin injections may be safe. Level IV.

Acute In Vitro and In Vivo Effects of Dexamethasone in the Vocal Folds: a Pilot Study.

Glucocorticoids (GC)s are commonly employed to treat vocal fold (VF) pathologies. However, VF atrophy has been associated with intracordal GC injections. Dexamethasone-induced skeletal muscle atrophy is well-documented in other tissues and believed to be mediated by increased muscle proteolysis via upregulation of Muscle Ring Finger (MuRF)-1 and Atrogin-1. Mechanisms of dexamethasone-mediated VF atrophy have not been described. This pilot study employed in vitro and in vivo models to investigate the effects of dexamethasone on VF epithelium, thyroarytenoid (TA) muscle, and TA-derived myoblasts. We hypothesized that dexamethasone will increase atrophy-associated gene expression in TA muscle and myoblasts and decrease TA muscle fiber size and epithelial thickness. In vitro, pre-clinical. TA myoblasts were isolated from a female Sprague-Dawley rat and treated with 1 μM dexamethasone for 24-h. In vivo, 15 New Zealand white rabbits were randomly assigned to three treatment groups: (1) bilateral intracordal injection of 40 μL dexamethasone (10 mg/ml; n=5), (2) volume-matched saline (n=5), and (3) untreated controls (n=5). Larynges were harvested 7-days post-injection. Across in vivo and in vitro experimentation, MuRF-1 and Atrogin-1 mRNA expression were measured via RT-qPCR. TA muscle fiber cross-sectional area (CSA) and epithelial thickness were also quantified in vivo. Dexamethasone increased MuRF-1 gene expression in TA myoblasts. Dexamethasone injection, however, did not alter atrophy-associated gene expression, TA CSA, or epithelial thickness in vivo. Dexamethasone increased atrogene expression in TA myoblasts, providing foundational insight into GC induced atrophic gene transcription. Repeated dexamethasone injections may be required to elicit atrophy in vivo. NA Laryngoscope, 133:2264-2270, 2023.

Intracordal injection therapy for vocal fold scarring: Steroid versus basic fibroblast growth factor.

ObjectivesVocal fold scarring is caused by replacement of vocal fold mucosa with fibrous tissue due to repeated inflammation or trauma. It can lead to severe dysphonia. It is currently treated conservatively and with phonosurgery and intracordal injections. Intracordal injection of steroid or basic fibroblast growth factor (bFGF) has been recently found to be useful for treating vocal fold scarring that does not respond to voice therapy.MethodsThis retrospective study involved the administration of steroid injection and bFGF injection bilaterally under local anesthesia in 16 patients each. Laboratory measurements of voice parameters were performed before and 3–6 months after injection.ResultsIn the steroid injection group, the Voice Handicap Index (VHI) score significantly improved from 57.1 to 40.5, total Grade, Roughness, Breathiness, Asthenia, Strain (tGRBAS) score significantly improved from 4.2 to 2.6, and mean speech fundamental frequency (SFF) increased from 192.5 to 211.4 dB, but there was no improvement in maximum phonation time (MPT) and mean airflow rate (MFR). In the bFGF injection group, significant improvements in the VHI score (from 53.3 to 35.7), MPT (from 16.9 to 21.8 s) and MFR (from 314.6 to 210.5 ml/s) were seen; however, the tGRBAS score did not improve. In addition, the SFF significantly decreased from 178.1 to 160.5 Hz.ConclusionThese results suggest that both steroid and bFGF injections are effective for treating vocal fold scarring, with steroids improving voice quality and bFGF improving glottic closure, thereby contributing to improvements in VHI scores.Level of Evidence4.

Effect of intracordal injection under local anesthesia on vital signs in high-risk patients

ObjectiveIntracordal injection under local anesthesia is widely performed; however, few studies show hemodynamic changes in the heart rate, blood oxygen saturation, and blood pressure during intracordal injection under local anesthesia. This study examined changes in vital signs (heart rate, blood oxygen saturation, systolic blood pressure, diastolic blood pressure) during intracordal injection under local anesthesia among high-risk patients and investigated whether intracordal injection under local anesthesia could be safely conducted. MethodsA retrospective chart review was adopted as the research design. We investigated the changes in vital signs (heart rate, blood oxygen saturation, blood pressure) before and after intracordal injection with basic fibroblast growth factor (bFGF) preparations under local anesthesia in 46 patients who visited our institution and developed unilateral vocal cord paralysis after a thoracic aortic aneurysm, thoracic aortic dissection surgery, thyroid disease, esophageal disease, idiopathic disease, etc. ResultsThe average operation time for the high-risk group was 3.67 minutes, with the shortest operating time being 2 minutes and the maximum operating time being 13 minutes. The average operation time for the control group was 3.73 minutes, with the shortest operating time being 1 minute and the maximum operating time being 9 minutes. Results before and after intracordal injection with bFGF preparations under local anesthesia for heart rate, blood oxygen saturation, systolic blood pressure, and diastolic blood pressure had P-values of 0.324, 0.394, 0.215, and 0.508, respectively, in the high-risk group, and no significant differences were found. Conversely, heart rate, blood oxygen saturation, systolic blood pressure, and diastolic blood pressure had P-values of 0.057, 0.232, 0.265, and 0.091, respectively, in the control group, and no significant differences were found. ConclusionIntracordal injection under local anesthesia may be safe, even for patients who require blood pressure management after thoracic aortic disease surgery.

Effects of Repeated Intracordal Glucocorticoid Injection on the Histology and Gene Expression of Rat Vocal Folds

Local injection of glucocorticoids (GCs) into the vocal folds has been used for treating the vocal fold lesions. While the positive effects on vocal fold nodules, polyps, or scarring have been clinically reported, some concern remains around the potential adverse effects such as vocal fold atrophy, and the mechanisms remain unclear. The present study examined the histology and gene expression of locally injected GC into the vocal folds in rats. Thirteen-week-old male Sprague-Dawley rats were used in the experiments. Triamcinolone acetonide (TAA) or saline were administered repeatedly to the right vocal folds at a weekly interval, and rats were euthanized one week after the last administration for histological examination. Genetic examination was assessed hyaluronic acid (HA) metabolism at 1 or 3 days after a single TAA injection by quantitative real-time polymerase chain reaction (qRT-PCR). The group which underwent four TAA injections showed a significant decrease in HA in the lamina propria (LP), thickness of the LP and total cell numbers of the LP compared with the saline group. In contrast, there was no significant difference in the area of collagen accumulation and the thyroarytenoid muscle, although there was a tendency of atrophy of the muscle. After single injection of TAA, qRT-PCR showed a significant decrease in the expression of HA synthases, Has2 and Has3. The current animal study first demonstrates that repeated intracordal injection of GCs may lead to atrophy of vocal folds caused by decrease of deposition of HA in the LP and decrease of gene expression of Has.

Outcomes of Esophageal Cancer after Esophagectomy in the Era of Early Injection Laryngoplasty.

(1) Background: severe weight loss was reported to be related to unilateral vocal fold paralysis (UVFP) after esophagectomy and could thus impair survival. Concomitant radical lymph node dissection along the recurrent laryngeal nerve during esophageal cancer surgery is controversial, as it might induce UVFP. Early intervention for esophagectomy-related UVFP by administering intracordal injections of temporal agents has recently become popular. This study investigated the survival outcomes of esophagectomy for esophageal squamous cell carcinoma (ESCC) after the introduction of early injection laryngoplasty (EIL). (2) Methods: a retrospective review of patients with ESCC after curative-intent esophagectomy was conducted in a tertiary referral medical center. The necessity of EIL with hyaluronic acid was comprehensively discussed for all symptomatic UVFP patients. The survival outcomes and related risk factors of ESCC were evaluated. (3) Results: among the cohort of 358 consecutive patients who underwent esophagectomy for ESCC, 42 (11.7%) showed postsurgical UVFP. Twenty-nine of them received office-based EIL. After EIL, the glottal gap area, maximum phonation time and voice outcome survey showed significant improvement at one, three and six months measurements. The number of lymph nodes in the resected specimen was higher in those with UVFP than in those without UVFP (30.1 ± 15.7 vs. 24.6 ± 12.7, p = 0.011). The Kaplan–Meier overall survival was significantly better in patients who had UVFP (p = 0.014), received neck anastomosis (p = 0.004), underwent endoscopic resection (p < 0.001) and had early-stage cancer (p < 0.001). Multivariate Cox logistic regression analysis showed two independent predictors of OS, showing that the primary stage and anastomosis type are the two independent predictors of OS. (4) Conclusion: EIL is effective in improving UVFP-related symptoms, thus providing compensatory and palliative measures to ensure the patient’s postsurgical quality of life. The emerging use of EIL might encourage cancer surgeons to radically dissect lymph nodes along the recurrent laryngeal nerve, thus changing the survival trend.

Intracordal Injection of Basic Fibroblast Growth Factor in 100 Cases of Vocal Fold Atrophy and Scar.

Vocal fold atrophy, scar, and sulcus reduce the vibratory function of the vocal fold mucosa, which causes severe refractory dysphonia. We have reported encouraging preliminary results using an intracordal injection of basic fibroblast growth factor (bFGF) and showed improvement in phonatory parameters and voice. The present study summarizes our experience with 100 cases of stiffened vocal folds that were treated with bFGF injections. Retrospective chart review with Interstitial Review Board (IRB) approval. Local injection of bFGF was performed in 100 cases of vocal fold pathology, which included 43 cases of vocal fold atrophy, 41 cases with scar, and 16 cases with sulcus. Ten micrograms of bFGF were injected into the vocal folds under topical anesthesia 4 times in each patient. Therapeutic outcomes were examined with maximum phonation time (MPT), voice handicap index-10 (VHI-10), and GRBAS scale. MPT, VHI-10, and GRBAS scores significantly improved in all pathology groups. An improvement on the VHI-10 greater than five points was observed in 82% of atrophy cases, 78% of scar cases, and 67% of sulcus cases. Improvement on the VHI-10 was significantly better in the atrophy group than the scar or sulcus groups. The mild/moderate cases of scar and sulcus showed better improvement than severe cases. The current large case series indicates positive effects of intracordal injection of bFGF for improvement of voice with no severe adverse events. The effects appeared best for cases of atrophy, while the treatment of severe scar and sulcus requires further improvement. 4 Laryngoscope, 131:2059-2064, 2021.

Early Management of Acute Unilateral Vocal Fold Paralysis: Update of the Literature

Unilateral vocal fold paralysis (UVFP) often leads to significant morbidity that may include dysphonia, swallowing problems and aspiration. The best timing for medialization procedures is still controversial. Published data suggest that early intracordal injection positively affects long-term outcomes. To critically review current literature in order to determine if early treatment of acute UVFP influences clinical outcomes of the patients. Nonsystematic literature review. A literature review was performed, using the Pubmed database. All relevant articles published in English addressing the effect of early treatment in acute unilateral focal fold paralysis were analyzed. Twenty-six articles were included due to their scientific interest. Published literature suggests that early intracordal injection in patients with UVFP reduces pulmonary infections, hospital length of stay and improves voice parameters. Also, patients who receive early intracordal injection seem to be less likely to undergo subsequent medialization thyroplasty. Early intracordal injection should be offered to patients with newly diagnosed UVFP since it promotes a satisfactory position of the vocal fold and seems to improve clinical outcomes. More investigation, with long-term follow up data and treatment randomization, is necessary to develop clinical consensus for these patients.

Surgical Treatment of Highly Breathy Dysphonia Due to Unilateral Vocal Fold Paralysis : Arytenoid Adduction Combined with Nerve-muscle Pedicle Flap Transfer

Improvement of breathy dysphonia due to unilateral vocal fold paralysis (UVFP) is usually achieved by implementing various kinds of phonosurgical procedures, including intracordal injection, type I thyroplasty, arytenoid adduction (AA), and combinations thereof. However, some patients do not recover their “normal” voices after surgery. Normal voices can be attained by providing the immobile vocal fold with the median location and symmetrical bulk and tension of the unaffected vocal fold. Because phonosurgical procedures offer “static” adjustment of these features, the thyroarytenoid muscle (TA) does not work as the body of the immobile vocal fold, resulting in little contribution to voice production and tuning. The authors refined the technique of nerve-muscle pedicle (NMP) flap implantation onto the TA muscle and have applied this innovative method, together with AA, in the treatment of breathy dysphonia due to UVFP since July 2002. Ninety-six patients had undergone NMP flap transfer and AA as of July 2016. The operative procedures are described in detail. Long-term follow-up over 2 years in 47 patients revealed significant improvement in the phonatory function after surgery. Furthermore, most parameters showed significant improvement during the follow-up period.

OnabotulinumtoxinA for adductor spasmodic dysphonia (ADSD): Functional results and the role of dosage

ObjectiveTo report the results of functional outcome, dose trend and relationship between onabotulinumtoxinA (onabotA) dosage and the severity of disease or time between therapy sessions in patients affected by adductor spasmodic dysphonia (ADSD). Patients and methodsThirty-two patients underwent 193 EMG-guided intracordal injections of a starting dose of 2 MU of onabotA. At enrollment, each subject was administered the VHI. The response was evaluated using a subjective rating scale (0–100% of normal phonation). ResultsThe quality of voice improved significantly after 1 month and stabilized by 3 months. The percentage of normal voice improved 33.34 ± 11.5% (min 26 – max 68). The functional gain was significantly worse in patients presenting with ADSD associated with dystonias in other body regions (31% vs 45% - p < 0.05). The mean dose employed was 3.64 MU (min 1 – max 6) with a trend of increasing dosages up to the 5th treatment after which the doses stabilized over time. The pre-treatment VHI showed a weakly positive correlation with the cumulative dose at the 5th and 10th injections. Benefit duration and the mean between treatment interval were 103 and 136 days respectively. The correlation between dose and inter-injection time is weakly negative (r = −0.22, p < 0.05), however, this is influenced predominantly by the first-to-second injection. After this initial treatment effect, the correlation becomes weakly positive (r = 0.12). ConclusionsOur data confirm the efficacy of onabotA to improve the quality of voice in cases of ADSD. The trial period for optimal dosage lasted up to a mean of five injections. The dosage of onabotA impacted the length of response and was influenced by the severity of ADSD. Finally the efficacy of onabotA did not change significantly after repeated administrations.

Efficacy of Two-dimensional Scanning Digital Kymography in Evaluation of Atrophic Vocal Folds

The purpose of this study was to evaluate the clinical feasibility and diagnostic accuracy of two-dimensional scanning digital kymography (2D DKG) in patients with vocal cord atrophy before and after treatment. We analyzed the characteristics of vocal fold vibration in five patients with unilateral vocal fold paralysis and five patients with presbyphonia. In patients with vocal cord paralysis, the status before and after intracordal injection was compared. Furthermore, in patients with presbyphonia, we compared the status before and after voice therapy (Seong-Tae Kim's laryngeal calibration technique). Quantitative parameters such as amplitude and phase symmetry indices, jitter, shimmer, noise-to-harmonic ratio, and maximum phonation time and qualitative parameters such as Voice Handicap Index, glottal gap, amplitude, and phase difference were used to evaluate the pre- and post-treatment status. In cases of vocal cord paralysis, vibratory changes of the vocal folds before and after intracordal injection could be identified immediately using 2D DKG. In overcorrection cases, all of the measured parameters were poor except for improvement of the glottal gap. In addition, 2D DKG showed appropriately the changes in vocal cord vibration before and after voice therapy in patients with presbyphonia. Two-dimensional DKG may be a useful diagnostic tool in evaluation of the vibratory characteristics of entire vocal cords. In addition, it may also play a role in providing a decision for treatment modalities.

Injection Laryngoplasty Using Autologous Fat Enriched with Adipose-Derived Regenerative Stem Cells: A Safe Therapeutic Option for the Functional Reconstruction of the Glottal Gap after Unilateral Vocal Fold Paralysis.

Background Paralysis of one vocal fold leads to glottal gap and vocal fold insufficiency that has significant impact upon a patient's quality of life. Fillers have been tested to perform intracordal injections, but they do not provide perdurable results. Early data suggest that enriching fat grafts with adipose-derived regenerative cells (ADRCs) promote angiogenesis and modulate the immune response, improving graft survival. The aim of this study is to propose ADRC-enriched adipose tissue grafts as effective filler for the paralyzed vocal fold to use it for functional reconstruction of the glottal gap. Method This is the first phase I-IIA clinical trial (phase I/IIA clinical trial, unicentric, randomized, controlled, and two parallel groups), to evaluate the safety of a new therapy with ADRC-enriched fat grafting (ADRC: group I) for laryngoplasty after unilateral vocal fold paralysis. Control group patients received centrifuged autologous fat (CAF: group II) grafts. Overall mean age is 52.49 ± 16.60 years. Group I (ADRC): 7 patients (3 males and 4 females), 52.28 ± 20.95 year. Group II (CAF): 7 patients (3 males and 4 females), 52.71 ± 12.59 year. Results VHI-10 test showed that preoperative mean score was 24.21 ± 8.28. Postoperative mean score was 6.71 ± 6.75. Preoperative result in group I was 21.14 ± 3.58 and postoperative result was 3.14 ± 3.53. Preoperative result for group II was 27.29 ± 10.66. Postoperative score in group II was 10.29 ± 7.52. Wilcoxon and the Student t-tests showed that the patient's self-perception of posttreatment improvement is larger when ADRCs are used. Comparing pre- and posttreatment voice quality analysis, group I showed a p = 0.053. Group II showed a p = 0.007. There would be no significant differentiation between pre- and posttreatment results. This is true for group II and limited for group I. Conclusions This prospective trial demonstrates the safety and efficacy of the treatment of glottal gap defects utilizing ADRC-enriched fat grafts. This trial is registered with NCT02904824.

Clinical Practicability of a Newly Developed Real-time Digital Kymographic System

A digital kymogram shows real images of vocal fold vibration. However, DKG is difficult to use in clinical practice because the recorded image cannot be seen instantaneously after examination, as considerable encoding time is required to visualize a digital kymogram. In addition, frame-by frame analysis should be implemented to evaluate high-speed videoendoscopy data, but is time- and labor-intensive. The purpose of the study was to validate the clinical practicability of a real-time multislice digital kymographic system developed by the authors. We analyzed the promptness and accuracy of the examination before and after intracordal injections in patients with unilateral vocal fold paralysis. To assess the clinical applicability of this system, six patients with unilateral vocal fold paralysis were selected. Real-time DKG was performed before and immediately after intracordal injection. We observed changes in the digital kymogram after the intracordal injection. Using this system, 10 scanning lines and up to five vertical pixel row could be obtained in real time, and the maximum acquisition time for the DKG image was 10 seconds. A digital kymogram of the patients could be instantaneously acquired, and whether the intracordal injection was appropriate or not. This article is the first validation study after the development of the real-time multislice digital kymographic system. Our system may be a promising tool in clinical practice for immediate assessment of the vibratory patterns of the vocal cords. More research is necessary for further clinical validation.

Efficacy of a Single Dose of Basic Fibroblast Growth Factor: Clinical Observation for 1 Year

Basic fibroblast growth factor promotes wound healing by accelerating healthy granulation and epithelialization. However, the duration of the effects of a single intracordal injection of basic fibroblast growth factor has not been established, and administration intervals and timing have yet to be standardized. Here, we administered a single injection to patients with insufficient glottic closure and conducted follow-up examinations with high-speed digital imaging to determine the duration of the treatment response. Case series. For treatment, 20 µg/mL recombinant human basic fibroblast growth factor was injected into two vocal cords. The following examinations were performed before the procedure and at 3-month intervals for 12 months starting at 1 month postinjection: Grade, Roughness, Breathiness, Asthenia, and Strain (GRBAS) scale assessment, maximum phonation time, acoustic analysis, high-speed digital imaging, glottal wave analysis, and kymographic analysis. Postinjection, the GRBAS scale score decreased, and the maximum phonation time was prolonged. In addition, the mean minimum glottal area and mean minimum glottal distance decreased. These changes were significant at 12 months postinjection compared with preinjection. However, there were no significant changes in the vibrations of the vocal cord margins. The intracordal injection of basic fibroblast growth factor improved insufficient glottic closure without reducing the vibrations of the vocal cord margins. This effect remained evident at 12 months postinjection. A single injection can be expected to yield a sufficient and persistent long-term effect.

Office-Based Intracordal Hyaluronate Injections Improve Quality of Life in Thoracic-Surgery-Related Unilateral Vocal Fold Paralysis.

Thoracic-surgery-related unilateral vocal fold paralysis (UVFP) may cause severe morbidity and can cause profound functional impairment and psychosocial stress in patients with pre-existing thoracic diseases. In-office intracordal hyaluronate (HA) injections have recently been applied to improve voice and quality of life in patients with vocal incompetence, but their effect on thoracic-surgery-related UVFP remains inconclusive. We therefore conducted a prospective study to clarify the effect of early HA injection on voice and quality of life in patients with thoracic-surgery-related UVFP. Patients with UVFP within 3 months after thoracic surgery who received office-based HA injection were recruited. Quantitative laryngeal electromyography, videolaryngostroboscopy, voice-related life quality (voice outcome survey), laboratory voice analysis, and health-related quality of life (SF-36) were evaluated at baseline, and at 1 month postinjection. A total of 104 consecutive patients accepted office-based HA intracordal injection during the study period, 34 of whom were treated in relation to thoracic surgery and were eligible for inclusion. Voice-related life quality, voice laboratory analysis, and most generic quality of life domains were significantly improved at 1 month after in-office HA intracordal injection. No HA-related complications were reported. Single office-based HA intracordal injection is a safe and effective treatment for thoracic-surgery-related UVFP, resulting in immediate improvements in patient quality of life, voice quality, and swallowing ability.

高速度撮影による声帯振動評価に基づく声帯内注入療法

高速度撮影による声帯振動評価に基づく声帯内注入療法

Glottal gap as an early predictor for permanent laryngoplasty in unilateral vocal fold paralysis

To assess the possible predictive factors for permanent laryngoplasty (PL) in patients with acute unilateral vocal fold paralysis (UVFP), and to assess the effects of early vocal cord hyaluronic acid injection. Prospective cohort study. Patients diagnosed with UVFP within the previous 6 months were enrolled. Initial and follow-up videolaryngostroboscopy, voice laboratory analysis, laryngeal electromyography, and Voice Outcome Survey were performed. Fifty newly diagnosed UVFP patients were recruited. Eight were excluded after 12 months of follow-up and data for 42 patients were analyzed. In patients treated conservatively, the glottal gap was measured on presentation. Normalized glottal gap area (NGGA) was the only predictor of PL (P = 0.036) according to multivariate logistic regression analysis. A cutoff value of 7.36 resulted in sensitivity of 85.7% and specificity of 80.0% for predicting future PL. The PL rate was significantly higher in patients with an initial NGGA > 7.36 compared with ≤ 7.36. (6/9 vs. 1/13; χ(2) = 6.71; P = 0.010). Among patients with an initial NGGA > 7.36, those who accepted early hyaluronic acid injection had a significantly lower rate of PL (1/11 vs. 6/9; χ(2) = 7.21; P = 0.007) and better social and emotional role functioning at follow-up. The glottal gap on presentation is a robust early predictor of PL. Early, office-based hyaluronic acid intracordal injection can reduce the need for PL in patients with a large NGGA.