Laryngeal Electromyography.

Laryngeal electromyography (LEMG) is an important diagnostic and prognostic tool in neurolaryngology. This chapter presents the advances in LEMG in the last 5 years based on clinical trials. LEMG is in most cases an office-based procedure for decision making in neurolaryngology. When performed in a standardized way, LEMG helps to differentiate abnormal function of the vocal folds from nonorganic disorders. It is mainly used to confirm the diagnosis of vocal fold paralysis (VFP) and is less frequently used for the diagnosis of myopathies and motor neuron disorders. Also, the value of LEMG for other diseases than VFP is presented. First consensus recommendations for standard performance of LEMG have been published. This will facilitate the comparison of results from different researchers in the future. For many years, LEMG focused on the thyroarytenoid muscle. Data are presented showing that now more and more studies are performed including other laryngeal muscles, most importantly the posterior cricoarytenoid muscle and cricothyroid muscle. Diagnostics and estimating the prognosis for patients with VFP remains the most important issue for LEMG. First meta-analyses are now available analyzing which LEMG parameters are the best prognosticators for recovery or persistent palsy. Due to the advances in multichannel LEMG, laryngeal nerve monitoring can now control the recurrent laryngeal nerve and the external branch of the superior laryngeal nerve during thyroid surgery. Finally, also the advances of LEMG for laryngeal pacing, guided laryngeal injections, laryngeal electrostimulation, and other indications beyond otolaryngology are discussed.

Patient-defined duration of benefit from juvederm (hyaluronic acid) used in injection laryngoplasty.

OBJECTIVES/HYPOTHESIS: Injection laryngoplasty has become valuable in treating laryngologic disorders including vocal cord atrophy, paralysis, and paresis. Although materials such as carboxymethylcellulose and calcium hydroxylapatite are Food and Drug Administration (FDA) approved, they are not without limitations. Juvederm (hyaluronic acid) is an alternative treatment that is not FDA approved. Although studies have examined Juvederm's longevity in cutaneous injections, there are limited data examining durability of Juvederm used in laryngoplasty. We aimed to determine the longevity and effectiveness of Juvederm used in injection laryngoplasty. STUDY DESIGN: Retrospective cohort study. METHODS: Subjects who underwent injection laryngoplasty using Juvederm were reviewed. Longevity was defined as the time between injection and the date that a patient first noted subjective deterioration of their voice. All subjects were subsequently followed using videostroboscopy to evaluate for Juvederm resorption. Longevity was analyzed using a Kaplan-Meier survival model, and effectiveness of laryngoplasty was determined using the Voice-Related Quality of Life index scores and analyzed using a Wilcoxon signed ranks test. RESULTS: Fifty-nine subjects met inclusion criteria and underwent Juvederm injection laryngoplasty. Kaplan-Meier survival analysis revealed a mean longevity of 10.6 months (95% confidence interval: 9.1-12.0 months). Wilcoxon signed ranks analysis of the pre- and postinjection Voice Related Quality of Life (VRQOL) scores revealed improvement, with a mean preinjection VRQOL of 49.2 (standard deviation [SD] = 25.8) and mean postinjection VRQOL of 68.2 (SD = 27.5) (P < .001). CONCLUSIONS: Injection laryngoplasty using Juvederm is an effective treatment for vocal cord atrophy, paralysis, and paresis. Knowledge of the patient-defined duration of benefit following laryngoplasty using Juvederm plays an important role in counseling patients as well as in the planning of future interventions. LEVEL OF EVIDENCE: 4 Laryngoscope, 129:2744-2747, 2019.

The incidence and recovery rate of idiopathic vocal fold paralysis: a population-based study.

PURPOSE: To determine the incidence and spontaneous recovery rate of idiopathic vocal fold paralysis (IVFP) and paresis (IVFp), and the impact of steroid treatment on rates of recovery. METHODS: This retrospective cohort study included all patients with IVFP or IVFp within a large integrated health-care system between January 1, 2008 and December 31, 2014. Patient demographics and clinical characteristics, including time to diagnosis, spontaneous recovery status, time to recovery, and treatment, were examined. RESULTS: A total of 264 patients were identified, 183 (69.3%) with IVFP and 81 (30.7%) with IVFp. Nearly all cases (96.6%) were unilateral and 89.8% of patients were over the age of 45. The combined (IVFP and IVFp) 7-year mean incidence was 1.04 cases per 100,000 persons each year with the highest 7-year mean annual incidence in white patients (1.60 per 100,000). The total rate of spontaneous recovery was 29.5%, where 21.2% had endoscopic evidence of resolution and 8.3% had clinical improvement in their voice without endoscopic confirmation. The median time to symptom resolution was 4.0 months. Use of steroids was not linked with spontaneous recovery in multivariable analyses. CONCLUSION: The annual incidence of VFP (IVFP and IVFp) was 1.04 cases per 100,000 persons, with spontaneous recovery occurring in nearly a third of patients, regardless of steroid use.

Recovery of Voice After Reconstruction of the Recurrent Laryngeal Nerve and Adjuvant Nimodipine.

BACKGROUND: Transection injury to the recurrent laryngeal nerve (RLN) has been associated with permanent vocal fold palsy, and treatment has been limited to voice therapy or local treatment of vocal folds. Microsurgical repair has been reported to induce a better function. The calcium channel antagonist nimodipine improves functional recovery after experimental nerve injury and also after cranial nerve injury in patients. This study aims to present voice outcome in patients who underwent repair of the RLN and received nimodipine during regeneration. METHODS: From 2002-2016, 19 patients were admitted to our center with complete unilateral injury to the RLN and underwent microsurgical repair of the RLN. After nerve repair, patients received nimodipine for 2-3 months. Laryngoscopy was performed repeatedly up to 14 months postoperatively. The Voice Handicap Index (VHI) was administered, and patients' maximum phonation time (MPT) was recorded during the follow-up. RESULTS: All patients recovered well after surgery, and nimodipine was well tolerated with no dropouts. None of the patients suffered from atrophy of the vocal fold, and some patients even showed a small ab/adduction of the vocal fold on the repaired side with laryngoscopy. During long-term follow-up (>3 years), VHI and MPT normalized, indicating a nearly complete recovery from unilateral RLN injury. CONCLUSIONS: In this cohort study, we report the results of the first 19 consecutive cases at our center subjected to reconstruction of the RLN and adjuvant nimodipine treatment. The outcome of the current strategy is encouraging and should be considered after iatrogenic RLN transection injuries.

Functional outcomes of endoscopic arytenoid abduction lateropexy for unilateral vocal cord paralysis with dyspnea.

In unilateral vocal cord paralysis (UVCP), hoarseness is usually the leading symptom; however, the diminished airway might lead to breathing problems as well, especially with exertion. The application of the classic resection glottis enlarging or medialization procedures might shift the breathing and/or the voice to a worse condition. The non-destructive endoscopic arytenoid abduction lateropexy (EAAL) might be a solution for this problem. The aim of our study was to analyze the phonatory and respiratory outcomes of this treatment concept. The first year phoniatric [Jitter, Shimmer, harmonics-to-noise ratio (HNR), maximum phonation time (MPT), fundamental frequency (F 0), Voice Handicap Index (VHI), Dysphonia Severity Index (DSI), Global-Roughness-Breathiness scale (GRB)], peak inspiratory flow (PIF), and quality of life (QoL) were evaluated in ten UVCP patients treated by EAAL for dyspnea generally presented on exertion. PIF, Jitter, QoL, GRB, and VHI significantly improved. DSI, HNR, and MPT got non-significantly better. F 0 slightly increased in all patients, a mild deterioration of shimmer was observed. These results prove that improving respiratory function is not necessarily associated with a deterioration in voice quality. The EAAL provides a significant improvement in breathing and the vibratory parameters of the postoperative, more tensed and straightened vocal cords proved to be more advantageous than the original (para) median 'loose' position. The over-adduction of the contralateral side more or less compensates for the disadvantageous, more lateral position of the operated side. EAAL might be an alternative treatment for unilateral vocal cord paralysis associated with breathing problems.

Unilateral Laryngeal Pacing System and Its Functional Evaluation.

Goal. To establish a reliable instrumental system for synchronized reactivation of a unilaterally paralyzed vocal fold and evaluate its functional feasibility. Methods. Unilateral vocal fold paralysis model was induced by destruction of the left recurrent laryngeal nerve (RLN) in anesthetized dogs. With a micro controller-based electronic system, electromyography (EMG) signals from cricothyroid (CT) muscle on the ipsilateral side were recorded and used to trigger pacing of paralyzed vocalis muscles. The dynamic movement of vocal folds was continuously monitored using an endoscope, and the opening and closing of the glottis were quantified with customized imaging processing software. Results. The recorded video images showed that left side vocal fold was obviously paralyzed after destructing the RLN. Using the pacing system with feedback triggering EMG signals from the ipsilateral CT muscle, the paralyzed vocal fold was successfully reactivated, and its movement was shown to be synchronized with the healthy side. Significance. The developed unilateral laryngeal pacing system triggered by EMG from the ipsilateral side CT muscle could be successfully used in unilateral vocal fold paralysis with the advantage of avoiding disturbance to the healthy side muscles.

Laryngeal pacing for bilateral vocal fold paralysis: Voice and respiratory aspects.

OBJECTIVE: To evaluate the effects of neurostimulation with the laryngeal pacemaker (LP) system in patients with bilateral vocal fold paralysis (BVFP) in terms of voice quality and respiratory function. STUDY DESIGN: Feasibility study, first-in-human, single-arm, open-label, prospective, multicenter study with group-sequential design and 6-month follow-up period, as described in details in our previous publication. METHODS: Nine symptomatic BVFP subjects were unilaterally implanted with the LP system at three study sites in Germany and Austria. Subjective and objective voice function, spirometric parameters other than peak expiratory/inspiratory flow (PEF/PIF), and PEF-meter self-assessment were evaluated pre- and 6 months postimplantation. RESULTS: In general, the LP system did not considerably change the voice quality of the implanted patients. Only the sound pressure level range improved significantly 6 months postimplantation (P = 0.018). The LP system implantation did not affect the glottal closure configuration, the duration of the closed phase, and the mucosal wave of the implanted side. The evaluated spirometric parameters were not significantly affected by laryngeal pacing, whereas PEF meter self-assessment showed a stable and significant (P = 0.028) improvement of the PEF within a week upon activation of the LP system. CONCLUSION: Neurostimulation with the LP system results in an immediate and stable PEF improvement, without negative effects on the voice quality. The PEF meter self-assessment confirmed the spirometry results of the PEF. The stimulated abduction did not affect the glottal closure during phonation. These results should be confirmed in larger and more homogenous patient cohorts. LEVEL OF EVIDENCE: 2b Laryngoscope, 127:1838-1844, 2017.

[On the problem of voice rehabilitation in the case of unilateral vocal fold paresis]. / O reabilitatsii golosa pri odnostoronnem pareze golosovykh skladok.

BACKGROUND: Unilateral vocal fold paresis (UVFP) significantly deteriorates the patient's quality of life. The leading role in the rehabilitation of the patients presenting with UVFP belongs to stimulation therapy which consists in the activation of muscle re-innervation of the larynx and the compensatory mechanisms allowing to achieve the most complete closure of the vocal folds during phonation. AIM: The objective of the present study was the optimization of the conservative treatment of patients with UVFP. MATERIAL AND METHODS: Fifty patients at the age varying from 18 to 70 years presenting with UVFP (the duration of the disease less than 6 months underwent the comprehensive treatment including electrostimulation of the larynx, vitamin therapy, and speech therapy. The patients were divided into two groups: A and B comprised of 25 subjects each. Those of Group A were given, in addition to the standard treatment, a 1.5 month-long course of Neuromidin therapy. The results of the treatment were evaluated with the use of laryngostroboscopy, flowmetry, the GRBAS scale, acoustic voice analysis (lingWaves), and the VHI questionnaire. RESULTS: The restoration of vocal fold mobility was achieved in 20% and 8% of the patients of groups A and B respectively. The clinical effect was absent in 12% of the patients in Group A and 28% of the patients in Group B. The differences between groups were statistically significant (p<0.05). In the remaining cases, the positive dynamics of the flowmetric characteristics, GRBAS and VHI data, maximum phonation time, Jitter, DSI, frequency and dynamic ranges as well as the intensity of voice were documented in 68% of patients in Group A and 64% of patients in Group B). CONCLUSION: The results of the study confirm the usefulness of the combined treatment of UVFP consisting of electrostimulation of the larynx together with speech therapy and application of cholinergic drugs. The addition of Neuromidin to the conventional scheme of conservative treatment can further improve its efficiency from 72% to 88%.

Reversing Age Related Changes of the Laryngeal Muscles by Chronic Electrostimulation of the Recurrent Laryngeal Nerve.

Age related atrophy of the laryngeal muscles -mainly the thyroarytenoid muscle (TAM)- leads to a glottal gap and consequently to a hoarse and dysphonic voice that significantly affects quality of life. The aim of our study was to reverse this atrophy by inducing muscular hypertrophy by unilateral functional electrical stimulation (FES) of the recurrent laryngeal nerve (RLN) in a large animal model using aged sheep (n = 5). Suitable stimulation parameters were determined by fatiguing experiments of the thyroarytenoid muscle in an acute trial. For the chronic trial an electrode was placed around the right RLN and stimulation was delivered once daily for 29 days. We chose a very conservative stimulation pattern, total stimulation time was two minutes per day, or 0.14% of total time. Overall, the mean muscle fiber diameter of the stimulated right TAM was significantly larger than the non-stimulated left TAM (30µm±1.1µm vs. 28µm±1.1 µm, p<0.001). There was no significant shift in fiber type distribution as judged by immunohistochemistry. The changes of fiber diameter could not be observed in the posterior cricoarytenoid muscle (PCAM). FES is a possible new treatment option for reversing the effects of age related laryngeal muscle atrophy.

In-Office Hyaluronate Injection Laryngoplasty as Palliative Treatment for Unilateral Vocal Fold Paralysis.

BACKGROUND: Voice and swallowing impairments can impact on both quality of life and survival. Unilateral vocal fold paralysis (UVFP) as a result of distant metastasis can cause breathy voice and aspiration. The purpose of this study is to develop and evaluate a less invasive and effective alternative therapy for UVFP. METHODS: This was a retrospective review of prospectively enrolled patients at a tertiary referral center in Taiwan. Among a cohort of 177 patients who received intracordal hyaluronate injections, 2 had UVFP from distant metastasis and met the inclusion criteria. Vocal cord motion was recorded by videostroboscopy, and the normalized glottal gap area was measured. Voice quality, defined by speech language pathologists, and swallowing status were compared, and immediate complications after the injection were investigated. RESULTS: Two patients with UVFP with M1 lesions (both lung) accepted the procedure. The glottal gap area was significantly improved 1 month after in-office hyaluronate injection. Voice quality and aspiration were also improved. No immediate complications were noted in either patient. CONCLUSIONS: In-office intracordal hyaluronate injection is a safe and effective treatment for UVFP, providing a palliative method to help maintain the patient's voice and quality of life.

Functional Electrical Stimulation of the Feline Larynx With a Flexible Ribbon Electrode Array.

OBJECTIVES: Success of laryngeal reanimation through neurorrhaphy has been limited by synkinesis and preoperative muscle atrophy. The objective of this study was to investigate the use of epimysial electrode arrays as a means of delivering electrical stimulation to the posterior cricoarytenoid muscles in order to control laryngeal abduction. METHODS: Ribbon electrode arrays with 4 or 8 electrode contacts were used. Four cats underwent implantation of electrode arrays along the surface of the posterior cricoarytenoid muscles. The glottis was visualized with a 0° telescope while electrodes were stimulated at different amplitudes and pulse-width durations. Recordings of stimulated vocal folds were analyzed, and the degree of vocal fold abduction was measured in order to create recruitment curves for the left and right posterior cricoarytenoid. Recruitment curves from electrode channels within the array were compared. RESULTS: Electrodes oriented along the medial aspect of the posterior cricoarytenoid stimulated graded physiologic degrees of abduction depending on the amplitude of stimulation. Electrodes oriented laterally along the posterior cricoarytenoid stimulated greater degrees of simultaneous adduction with abduction. CONCLUSION: Acute studies of ribbon surface electrode arrays placed onto the posterior cricoarytenoid reproduce graded degrees of abduction necessary for the precise function of respiration and speech.

Magnetic Control of the Glottic Opening in an Ex Vivo Sheep Larynx Model: A Preliminary Study.

OBJECTIVE/HYPOTHESIS: So far, a number of techniques have been described for the treatment of bilateral vocal fold paralysis. These techniques were reported to be successful in maintaining an adequate airway but also found to be associated with an increased risk of aspiration, dysphonia, and granulation tissue formation at the operation site. We aimed to investigate the effectiveness of a novel mucosa-sparing technique based on the generation of a magnetic field within the larynx for the tailored lateralization of the ipsilateral vocal fold. STUDY DESIGN: This is an ex vivo experimental study. METHODS: Twenty sheep larynges that were procured from the local slaughterhouse were used as a model. For each specimen, two neodymium (Nd) disc magnets with marked poles were used to create a unilateral attractive magnetic force at the glottic level. Following insertion of the magnets, the level of vocal fold lateralization was assessed under an operating microscope. The results were analyzed for their statistical significance. RESULTS: Before the procedure, the mean value of the glottic openings of all the specimens was 4.985 mm. The postprocedure mean value was 5.640 mm. The mean amount of increase in the glottic openings after the procedure was 0.655 mm. This change was found to be statistically significant (P < 0.05). CONCLUSIONS: A statistically significant increase in the cross-sectional area of the glottic region could be achieved. The mucosal integrity of the laryngeal airway was also preserved. The idea of "magnetic control of the glottic airway" is a novel concept but seems to be a promising option.

Effects of Functional Electrical Stimulation on Denervated Laryngeal Muscle in a Large Animal Model.

Bilateral vocal fold paralysis (BVCP) is a life-threatening condition that follows injury to the Recurrent Laryngeal nerve (RLn) and denervation of the intrinsic laryngeal musculature. Functional electrical stimulation (FES) enables restoration and control of a wide variety of motor functions impaired by lower motor neuron lesions. Here we evaluate the effects of FES on the sole arytenoid abductor, the posterior cricoarytenoid (PCA) muscle in a large animal model of RLn injury. Ten horses were instrumented with two quadripolar intramuscular electrodes in the left PCA muscle. Following a 12-week denervation period, the PCA was stimulated using a once-daily training session for 8 weeks in seven animals. Three animals were used as unstimulated controls. Denervation produced a significant increase in rheobase (P < 0.001). Electrical stimulation produced a 30% increase in fiber diameter in comparison with the unstimulated control group (33.9 ± 2.6 µm FES+, 23.6 ± 4.2 µm FES-, P = 0.04). A trend toward a decrease in the proportion of type 1 (slow) fibers and an increase in type 2a (fast) fibers was also observed. Despite these changes, improvement in PCA function at rest was not observed. These data suggest that electrical stimulation using a relatively conservative set of stimulation parameters can reverse the muscle fiber atrophy produced by complete denervation while avoiding a shift to a slow (type 1) fiber type.

Development of a nerve conduction technique for the recurrent laryngeal nerve.

OBJECTIVES/HYPOTHESIS: To develop a reliable and safe laryngeal nerve conduction technique and to obtain consistent parameters as normal reference values. STUDY DESIGN: A prospective single-arm study. METHODS: A nerve conduction test was performed on the contralateral normal side in 42 patients with unilateral vocal fold palsy. The recording was performed in the intact thyroarytenoid muscle using a monopolar needle. The electrical stimulation using a 37-mm monopolar needle was applied 3 cm below the lower margin of the cricoid cartilage, just lateral to the trachea and medial to the carotid artery, and its intensity was gradually increased until the amplitude of the electrical response reached the maximum level. The latency of the evoked muscle response was acquired at the first evoked waveform deflection from the baseline. RESULTS: The average latency of the recurrent laryngeal nerves was 1.98 ± 0.26 ms. The latencies showed normal distribution according to the quantile-quantile plot and Kolmogorov-Smirnov test (P = .098). There was no significant difference in latencies between the right and left recurrent laryngeal nerves. Anthropometric factors including height and weight did not show any correlation with the latencies. CONCLUSIONS: We developed a reliable and safe laryngeal nerve conduction technique and obtained normal reference values for the recurrent laryngeal nerve conduction study. This laryngeal nerve conduction study can be an additional tool for detecting recurrent laryngeal nerve injury if it is performed in combination with the conventional laryngeal electromyography. LEVEL OF EVIDENCE: 4.

Injection laryngoplasty in the outpatient clinic under local anaesthetic: a case series of sixty-eight patients.

OBJECTIVES: We aimed to assess self-report and perceptual voice outcomes in patients undergoing local anaesthetic injection laryngoplasty in our outpatient clinic. DESIGN: Prospective case series. SETTING: Department of Otolaryngology-Head and Neck Surgery, Freeman Hospital, Newcastle-upon-Tyne, UK. PARTICIPANTS: Sixty-eight patients underwent local anaesthetic injection laryngoplasty in the outpatient clinic over the 2-year study period. MAIN OUTCOME MEASURE: Voice Performance Questionnaire (patient-rated), and perceptual voice analysis (observer-rated) Grade, Roughness, Breathiness, Aesthenia and Strain scores were recorded before and 2 weeks after injection laryngoplasty. RESULTS: Fifty-seven patients had sufficient pre- and post-procedure data to be included in the analysis. These included 32 men and 25 women, age range 26-97 years. Of the remaining patients, they were excluded due to failed procedure (n = 3), too unwell to proceed (n = 1), died before follow-up was complete (n = 3) and incomplete data (n = 4). The median Voice Performance Questionnaire score improved from 42 to 21; (P < 0.0001). Significant improvements were seen in all parameters of Grade, Roughness, Breathiness, Aesthenia, Strain. CONCLUSION: Injection laryngoplasty under local anaesthetic in the outpatient clinic generates improvements in subjective and perceptual voice outcomes similar to those obtained in the operating room under general anaesthetic or sedation. Complication rates between these procedures were also comparable. Injection laryngoplasty under local anaesthetic is timely, cost-effective and obviates need for general anaesthesia in patients, many of whom have comorbidities and diminished life expectancy.

[Dexmedetomidine is useful for sedation during laryngoplasty with voice monitoring].

BACKGROUND: Laryngoplasty is an operation for voice reconstruction performed for recurrent laryngeal nerve palsy, and this operation needs intraoperative speech monitoring. Previously, all procedures were performed under local anesthesia. Therefore, patients were suffering, and otolaryngologists had difficulty because of patients' coughs and laryngeal movements. We used dexmedetomidine (DEX) with local anesthesia for laryngoplasty. METHODS: We retrospectively examined 6 patients who had undergone laryngoplasty from January 2008 to October 2010. Patients received local anesthesia for pain control and DEX for sedation. Anesthesiologists achieved adequate sedation level (Ramsay's score 3-4) with DEX. RESULTS: Sedation was induced with 6 microg x kg(-1). hr(-1) of DEX for 10 minutes. All patients were maintained at 0.2-1.2 microg x kg(-1) x hr(-1). A local anesthetic(8.6 +/- 2.3 ml of 1% lidocaine 1 : 100,000 epinephrine) was used. During the initial loading of DEX, the patients' vital signs were stable. DEX suppressed coughs and laryngeal movements and did not cause respiratory depression. They were able to respond to the otolaryngologists' demand for a voice test. CONCLUSIONS: Dexmedetomidine was useful for sedation during laryngoplasty with voice monitoring.

Synchronous electrical stimulation of laryngeal muscles: an alternative for enhancing recovery of unilateral recurrent laryngeal nerve paralysis.

BACKGROUND: Although electrical stimulation of the larynx has been widely studied for treating voice disorders, its effectiveness has not been assessed under safety and comfortable conditions. This article describes design, theoretical issues, and preliminary evaluation of an innovative system for transdermal electrical stimulation of the larynx. The proposed design includes synchronization of electrical stimuli with laryngeal neuromuscular activity. OBJECTIVE: To study whether synchronous electrical stimulation of the larynx could be helpful for improving voice quality in patients with dysphonia due to unilateral recurrent laryngeal nerve paralysis (URLNP). MATERIALS AND METHODS: A 3-year prospective study was carried out at the Instituto Nacional de Rehabilitacion in the Mexico City. Ten patients were subjected to transdermal current electrical stimulation synchronized with the fundamental frequency of the vibration of the vocal folds during phonation. The stimulation was triggered during the phase of maximum glottal occlusion. A complete acoustic voice analysis was performed before and after the period of electrical stimulation. RESULTS: Acoustic analysis revealed significant improvements in all parameters after the stimulation period. CONCLUSION: Transdermal synchronous electrical stimulation of vocal folds seems to be a safe and reliable procedure for enhancing voice quality in patients with (URLNP).

Neuromuscular electrical stimulation of the cricothyroid muscle in patients with suspected superior laryngeal nerve weakness.

In this retrospective case study, we report the apparent clinical effectiveness of neuromuscular electrical stimulation (NMES) in combination with voice therapy (VT) for rehabilitating dysphonia secondary to suspected superior laryngeal nerve (SLN) weakness in two female patients. Both patients failed or plateaued with traditional VT but had significant improvement with the addition of NMES of the cricothyroid muscle and SLN using a VitalStim unit. Stimulation was provided simultaneously with voice exercises based on musical phonatory tasks. Both acoustic analysis and endoscopic evaluation demonstrated important improvements after treatment. In the first patient, the major change was obtained within the primo passaggio region; specifically, a decrease in voice breaks was demonstrated. In the second patient, an improvement in voice quality (less breathiness) and vocal range were the most important findings. Additionally, each patient reported a significant improvement in their voice complaints. Neuromuscular laryngeal electrical stimulation in combination with vocal exercises might be a useful tool to improve voice quality in patients with SLN injury.

Glottal insufficiency with aspiration risk in dysphagia.

Glottal closure is an important part of the mechanism that protects the airway during the normal swallow. Glottal insufficiency disrupts glottal closure and therefore puts patients at risk of aspiration. Treatment of glottal insufficiency can be classified as surgical or nonsurgical. The objective of treating glottal insufficiency is to avoid aspiration or penetration of secretions or food into the airway. Nonsurgical treatment consists of swallowing maneuvers and other measures. Surgical treatment of glottal insufficiency includes injection laryngoplasty, medialization thyroplasty with or without arytenoid adduction or with arytenopexy and cricothyroid subluxation, hypopharyngoplasty, cricopharynx muscle dilation, and cricopharynx myotomy.