Stimulation of the Internal Superior Laryngeal Nerve as a Potential Therapy for Obstructive Sleep Apnea in a Porcine Model.

Impaired pharyngeal sensing of negative pressure can lead to a blunted response of the upper airway dilator muscles and contribute to the development of obstructive sleep apnea (OSA). This response is modulated by the nerve fibers in the internal branch of the superior laryngeal nerve (iSLN), mediating negative pressure sensation. Artificial excitation of these fibers could be a potential treatment target for OSA. To evaluate this, electrostimulation of the iSLN was performed in a porcine isolated upper airway model. Artificial obstructions were induced by varying levels of negative pressure and the ability of the animal to resolve these obstructions was evaluated. The pressure at which the animal was still able to resolve the obstruction was quantified as 'Resolvable Pressure'. Thereby, the effects on pharyngeal patency (n=35) and the duration of the therapeutic effect outlasting the stimulation (n=6) were quantified. Electrostimulation prior to the introduction of an artificial obstruction improved the median resolvable pressure from -28.3 cmH2O [IQR: -45.9; -26.1] to -92.6 cmH2O [IQR: -105.1; -78.6]. The median therapeutic effect was found to outlast the last stimulation burst applied by 163 s when five stimulation bursts were applied in short succession [IQR: 58; 231], 58 s when two were applied [IQR: 7; 65], and 6 s when one was applied [IQR: 0; 51]. Stimulation of the iSLN increased EMG in the genioglossus. The proposed treatment concept can improve pharyngeal patency in the model. Transfer of the results to clinical application could enable the development of a new neuromodulation therapy for OSA.

Targeted Hypoglossal Nerve Stimulation for Patients With Obstructive Sleep Apnea: A Randomized Clinical Trial.

Importance: Evidence is lacking from randomized clinical trials of hypoglossal nerve stimulation in obstructive sleep apnea (OSA). Objective: To evaluate the safety and effectiveness of targeted hypoglossal nerve stimulation (THN) of the proximal hypoglossal nerve in patients with OSA. Design, Setting, and Participants: This randomized clinical trial (THN3) was conducted at 20 centers and included 138 patients with moderate to severe OSA with an apnea-hypopnea index (AHI) of 20 to 65 events per hour and body mass index (calculated as weight in kilograms divided by height in meters squared) of 35 or less. The trial was conducted from May 2015 through June 2018. Data were analyzed from January 2022 through January 2023. Intervention: Implant with THN system; randomized 2:1 to activation at month 1 (treatment) or month 4 (control). All received 11 months of THN with follow-up at months 12 and 15, respectively. Main Outcomes and Measures: Primary effectiveness end points comprised AHI and oxygen desaturation index (ODI) responder rates (RRs). Treatment responses at months 4 and 12/15 were defined as a 50% or greater reduction in AHI to 20 or less per hour and an ODI decrease of 25% or greater. Coprimary end points comprised (1) month 4 AHI and ODI RR in the treatment greater than the control group and (2) month 12/15 AHI and ODI RR in the entire cohort exceeding 50%. Secondary end points included sleep apnea severity (AHI and ODI) and patient-reported outcomes (Epworth Sleepiness Scale, Functional Outcomes of Sleep Questionnaire, and EQ-5D visual analog scale). Results: Among 138 participants, the mean (SD) age was 56 (9) years, and 19 (13.8%) were women. Month 4 THN RRs were substantially greater in those in the treatment vs control group (AHI, 52.3% vs 19.6%; ODI, 62.5% vs 41.3%, respectively) with treatment-control standardized mean differences of 0.725 (95% CI, 0.360-1.163) and 0.434 (95% CI, 0.070-0.843) for AHI and ODI RRs, respectively. Months 12/15 RRs were 42.5% and 60.4% for AHI and ODI, respectively. Improvements in AHI, ODI, Epworth Sleepiness Scale, Functional Outcomes of Sleep Questionnaire, and EQ-5D visual analog scale scores were all clinically meaningful (medium to large effect size). Two serious adverse events and 100 nonserious related adverse events were observed from the implant procedure or study protocol. Conclusions and Relevance: This randomized clinical trial found that THN demonstrated improvements in sleep apnea, sleepiness, and quality of life in patients with OSAs over an extended AHI and body mass index range without prior knowledge of pharyngeal collapse pattern. Clinically meaningful improvements in AHI and patient-reported responses compared favorably with those of distal hypoglossal nerve stimulation trials, although clinically meaningful differences were not definitive for ODI. Trial Registration: ClinicalTrials.gov Identifier: NCT02263859.

Long-Term Generator Replacement Experience in Hypoglossal Nerve Stimulator Therapy Recipients With CPAP-Intolerant Obstructive Sleep Apnea.

OBJECTIVE: In the last decade, hypoglossal nerve stimulation (HNS) has emerged as a therapeutic alternative for patients with obstructive sleep apnea. The original clinical trial cohorts are entering the phase of expected battery depletion (8-12 years). This study aimed to examine the surgical experience with implantable pulse generator (IPG) replacements and the associated long-term therapy outcomes. STUDY DESIGN: Retrospective analysis of patients from the original clinical trial databases (STAR, German post-market) who were followed in the ongoing ADHERE registry. SETTING: International multicenter HNS registry. METHODS: The ADHERE registry and clinical trial databases were cross-referenced to identify the serial numbers of IPGs that were replaced. Data collection included demographics, apnea-hypopnea index (AHI), therapy use, operative times, and adverse events. RESULTS: Fourteen patients underwent IPG replacement 8.3 ± 1.1 years after their initial implantation. Body mass index was unchanged between the original implant and IPG replacement (29 ± 4 vs 28 ± 2 kg/m2 , p = .50). The mean IPG replacement operative time was shorter than the original implant (63 ± 50 vs 154 ± 58 minutes, p < .002); however, 2 patients required stimulation lead replacement which significantly increased operative time. For patients with available AHI and adherence data, the mean change in AHI from baseline to latest follow-up (8.7 ± 1.1 years after de novo implant) was -50.06%, and the mean therapy use was 7.2 hours/night. CONCLUSION: IPG replacement surgery was associated with low complications and shorter operative time. For patients with available outcomes data, adherence and efficacy remained stable after 9 years of follow-up.

[Sleep medicine for the ENT specialist]. / Schlafmedizin für den Hals-Nasen-Ohren-Facharzt.

Sleep-related breathing disorders can be divided into obstructive and central sleep apnea, and hypoventilation syndromes. The diagnosis is made according to an algorithm in which clinical symptoms and a polygraphy or polysomnography usually point the way. After initial diagnosis of the most common obstructive sleep apnea, conservative therapies such as positive airway pressure therapy (PAP therapy), positional therapy, and/or mandibular advancement splint are used in many cases, supplemented by treatment of risk factors. If PAP therapy is not possible, more detailed diagnosis of airway obstruction, often with sleep videoendoscopy, is required. In general, "muscle-sparing" surgical techniques such as tonsillectomy with uvulapalatopharyngoplasty (TE-UPPP) should be considered whenever possible. This is especially important in the surgical treatment of snoring. More surgical therapy alternatives are for example barbed wire pharyngoplasty, tongue pacemaker and bimaxillary advancement. Optimal therapy alternatives should be evaluated in a sleep medicine center.

Hypoglossal nerve stimulation for obstructive sleep apnea: updated position paper of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery.

Since the first statement of the German Society of Oto-Rhino-Laryngology, hypoglossal nerve stimulation (HNS) is meanwhile an established treatment option for obstructive sleep apnea (OSA). There are three HNS systems available in Germany which differ in their technical details of the underlying comparable basic principle. For the unilateral HNS with respiratory sensing, several comparative studies, high-volume register analysis and long-term reports exist. The continuous HNS without respiratory sensing does not require a sleep endoscopy for indication. For the bilateral continuous HNS as the single partially implantable device, a feasibility study exists. For indication, the assessment of positive airway pressure failure by sleep medicine is crucial, and the decision for HNS should be made in discussion of other treatment options for at least moderate OSA. The implantation center holds primarily responsibility among the interdisciplinary sleep team and is primary contact for the patient in problems. This depicts why structural processes are required to secure outcome quality and minimize the complications. The aftercare of HNS patients can be provided interdisciplinary and by different medical institutions, whereat, minimal reporting standards to document outcome and usage are recommended.

[Hypoglossal Nerve Stimulation in the Treatment of Obstructive Sleep Apnea]. / Die Hypoglossus-Stimulation zur Therapie der obstruktiven Schlafapnoe.

Reduced genioglossus muscle tone is considered one of the major causes for obstructive sleep apnea (OSA). Hypoglossal nerve stimulation (HNS) keeps the upper airway patent by increasing the muscle tone of the genioglossus muscle being the major airway opener. According to the German S3-Guideline on Sleep Disordered Breathing this treatment is indicated in patients with OSA failing or rejecting positive airway pressure, showing an AHI between 15 and 65, in particular when anatomy is normal and the BMI below 35. In 2021 it has been made available for regular patient care in Germany. However, breathing synchronized, continuous, and bilateral HNS differ in parts relevantly regarding their patient selection criteria, technical features, surgical technique, therapy setting and programming, and daily use for the patient. There are many publications showing the safety, efficacy, and patient satisfaction of breathing synchronized HNS. Less but promising data are available for continuous and the most recent bilateral HNS.

Impact of Body Mass Index and Discomfort on Upper Airway Stimulation: ADHERE Registry 2020 Update.

OBJECTIVES/HYPOTHESIS: To provide the ADHERE registry Upper Airway Stimulation (UAS) outcomes update, including analyses grouped by body mass index (BMI) and therapy discomfort. STUDY DESIGN: Prospective observational study. METHODS: ADHERE captures UAS outcomes including apnea-hypopnea index (AHI), Epworth sleepiness scale (ESS), therapy usage, patient satisfaction, clinician assessment, and safety over a 1-year period. BMI ≤32 kg/m2 (BMI32 ) and 32 < BMI ≤35 kg/m2 (BMI35 ) group outcomes were examined. RESULTS: One thousand eight hundred forty-nine patients enrolled in ADHERE, 1,019 reached final visit, 843 completed the visit. Significant changes in AHI (-20.9, P < .0001) and ESS (- 4.4, P < .0001) were demonstrated. Mean therapy usage was 5.6 ± 2.2 hr/day. Significant therapy use difference was present in patients with reported discomfort versus no discomfort (4.9 ± 2.5 vs. 5.7 ± 2.1 hr/day, P = .01). Patients with discomfort had higher final visit mean AHI versus without discomfort (18.9 ± 18.5 vs. 13.5 ± 13.7 events/hr, P = .01). Changes in AHI and ESS were not significantly different. Serious adverse events reported in 2.3% of patients. Device revision rate was 1.9%. Surgical success was less likely in BMI35 versus BMI32 patients (59.8% vs. 72.2%, P = .02). There was a significant therapy use difference: 5.8 ± 2.0 hr/day in BMI32 versus 5.2 ± 2.2 hr/day in BMI35 (P = .028). CONCLUSIONS: Data from ADHERE demonstrate high efficacy rates for UAS. Although surgical response rate differs between BMI32 and BMI35 patient groups, the AHI and ESS reduction is similar. Discomfort affects therapy adherence and efficacy. Thus, proper therapy settings adjustment to ensure comfort is imperative to improve outcomes. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:2616-2624, 2021.

Intra- and Extrathoracic Malignant Tracheoesophageal Fistula-A Differentiated Reconstructive Algorithm.

BACKGROUND: Tracheoesophageal fistulae (TEF) after oncologic resections and multimodal treatment are life-threatening and surgically challenging. Radiation and prior procedures hamper wound healing and lead to high complication rates. We present an interdisciplinary algorithm for the treatment of TEF derived from the therapy of consecutive patients. PATIENTS AND METHODS: 18 patients (3 females, 15 males) treated for TEF from January 2015 to July 2017 were included. Two patients were treated palliatively, whereas reconstructions were attempted in 16 cases undergoing 24 procedures. Discontinuity resection and secondary gastric pull-up were performed in two patients. Pedicled reconstructions were pectoralis major (n = 2), sternocleidomastoid muscle (n = 2), latissimus dorsi (n = 1) or intercostal muscle (ICM, n = 7) flaps. Free flaps were anterolateral thigh (ALT, n = 4), combined anterolateral thigh/anteromedial thigh (ALT/AMT, n = 1), jejunum (n = 3) or combined ALT-jejunum flaps (n = 2). RESULTS: Regarding all 18 patients, 11 of 16 reconstructive attempts were primarily successful (61%), whereas long-term success after multiple procedures was possible in 83% (n = 15). The 30-day survival was 89%. Derived from the experience, patients were divided into three subgroups (extrathoracic, cervicothoracic, intrathroracic TEF) and a treatment algorithm was developed. Primary reconstructions for extra- and cervicothoracic TEF were pedicled flaps, whereas free flaps were used in recurrent or persistent cases. Pedicled ICM flaps were mostly used for intrathoracic TEF. CONCLUSION: TEF after multimodal tumor treatment require concerted interdisciplinary efforts for successful reconstruction. We describe a differentiated reconstructive approach including multiple reconstructive techniques from pedicled to chimeric ALT/jejunum flaps. Hereby, successful reconstructions are mostly possible. However, disease and patient-specific morbidity has to be anticipated and requires further interdisciplinary management.

Effect of Upper Airway Stimulation in Patients with Obstructive Sleep Apnea (EFFECT): A Randomized Controlled Crossover Trial.

BACKGROUND: Several single-arm prospective studies have demonstrated the safety and effectiveness of upper airway stimulation (UAS) for obstructive sleep apnea. There is limited evidence from randomized, controlled trials of the therapy benefit in terms of OSA burden and its symptoms. METHODS: We conducted a multicenter, double-blinded, randomized, sham-controlled, crossover trial to examine the effect of therapeutic stimulation (Stim) versus sham stimulation (Sham) on the apnea-hypopnea index (AHI) and the Epworth Sleepiness Scale (ESS). We also examined the Functional Outcomes of Sleep Questionnaire (FOSQ) on sleep architecture. We analyzed crossover outcome measures after two weeks using repeated measures models controlling for treatment order. RESULTS: The study randomized 89 participants 1:1 to Stim (45) versus Sham (44). After one week, the AHI response rate was 76.7% with Stim and 29.5% with Sham, a difference of 47.2% (95% CI: 24.4 to 64.9, p < 0.001) between the two groups. Similarly, ESS was 7.5 ± 4.9 with Stim and 12.0 ± 4.3 with Sham, with a significant difference of 4.6 (95% CI: 3.1 to 6.1) between the two groups. The crossover phase showed no carryover effect. Among 86 participants who completed both phases, the treatment difference between Stim vs. Sham for AHI was -15.5 (95% CI -18.3 to -12.8), for ESS it was -3.3 (95% CI -4.4 to -2.2), and for FOSQ it was 2.1 (95% CI 1.4 to 2.8). UAS effectively treated both REM and NREM sleep disordered breathing. CONCLUSIONS: In comparison with sham stimulation, therapeutic UAS reduced OSA severity, sleepiness symptoms, and improved quality of life among participants with moderate-to-severe OSA.

Improving outcomes of hypoglossal nerve stimulation therapy: current practice, future directions, and research gaps. Proceedings of the 2019 International Sleep Surgery Society Research Forum.

Hypoglossal nerve stimulation (HGNS) has evolved as a novel and effective therapy for patients with moderate-to-severe obstructive sleep apnea. Despite positive published outcomes of HGNS, there exist uncertainties regarding proper patient selection, surgical technique, and the reporting of outcomes and individual factors that impact therapy effectiveness. According to current guidelines, this therapy is indicated for select patients, and recommendations are based on the Stimulation Therapy for Apnea Reduction or STAR trial. Ongoing research and physician experiences continuously improve methods to optimize the therapy. An understanding of the way in which airway anatomy, obstructive sleep apnea phenotypes, individual health status, psychological conditions, and comorbid sleep disorders influence the effectiveness of HGNS is essential to improve outcomes and expand therapy indications. This article presents discussions on current evidence, future directions, and research gaps for HGNS therapy from the 10th International Surgical Sleep Society expert research panel. CITATION: Suurna MV, Jacobowitz O, Chang J, et al. Improving outcomes of hypoglossal nerve stimulation therapy: current practice, future directions and research gaps. Proceedings of the 2019 International Sleep Surgery Society Research Forum. J Clin Sleep Med. 2021;17(12):2477-2487.

Die Stimulation des Nervus hypoglossus in der Behandlung der obstruktiven Schlafapnoe ­ Aktualisiertes Positionspapier der Arbeitsgemeinschaft Schlafmedizin der DGHNO-KHC.

Hypoglossal nerve stimulation for obstructive sleep apnea - Updated position paper of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery. Since the first statement of the German Society of Oto-Rhino-Laryngology, hypoglossal nerve stimulation (HNS) is meanwhile an established treatment option for obstructive sleep apnea (OSA). There are three HNS systems available in Germany which differ in their technical details of the underlying comparable basic principle. For the unilateral HNS with respiratory sensing, several comparative studies, high-volume register analysis and long-term reports exist. The continuous HNS without respiratory sensing does not require a sleep endoscopy for indication. For the bilateral continuous HNS as the single partially implantable device, a feasibility study exists. For indication, the assessment of positive airway pressure failure by sleep medicine is crucial, and the decision for HNS should be made in discussion of other treatment options for at least moderate OSA. The implantation center holds primarily responsibility among the interdisciplinary sleep team and is primary contact for the patient in problems. This depicts why structural processes are required to secure outcome quality and minimize complications. The aftercare of HNS patients can be provided interdisciplinary and by different medical institutions whereat minimal reporting standards to document outcome and usage are recommended.

Nightly Hypoxia Does Not Seem to Lead to Otolith Dysfunction in Patients With Obstructive Sleep Apnea.

OBJECTIVES: Obstructive sleep apnea (OSA) is a common sleep disorder, which is associated with recurrent oxygen desaturation during sleep. It has already been shown that nocturnal hypoxia may lead to cochlear dysfunction in patients with OSA. Less is known whether hypoxia during sleep also impacts vestibular function in those patients. Thus, the aim of the presented study was to assess a potential vestibulotoxic effect of nightly desaturations with hypoxia in patients with OSA by investigating a possible correlation between respiratory parameters and vestibular function tests. METHODS: A total of 56 patients were included in the study and underwent a fully attended cardiorespiratory polysomnography (PSG). Vestibular function was assessed using video head impulse test to evaluate horizontal semicircular canal function and cervical vestibular evoked myogenic potentials (cVEMPs) and ocular vestibular evoked myogenic potentials (oVEMPs) to measure otolith function. Descriptive data analysis was conducted and correlation analysis between selected PSG parameters and the results of vestibular testing was performed using Kendall τ coefficient. RESULTS: A significant correlation between vestibular function and respiratory polysomnographic parameters could not be demonstrated in the study (P > .05) but cVEMP and oVEMP results showed a trend toward a correlation with oxygen desaturation indices and apnea-hypopnea index. Additionally, otolith hypofunction was more prevalent in patients with hypertension as well as OSA. CONCLUSION: The results of our study show that there is no significant correlation between vestibular function and sleep apnea parameters, although otolith dysfunction might be more prevalent in patients with OSA and hypertension.

Maximum isometric tongue force in patients with obstructive sleep apnoea.

BACKGROUND: Obstructive sleep apnea (OSA) is a sleep disorder with a prevalence of 9-38%. The underlying pathology in OSA is a collapse of the upper airway. Especially in more severely affected patients, this collapse is often located at the level of the tongue base. Therefore, various implantable systems (anchors and ligament techniques) were developed to prevent or overcome this collapse. These systems are exposed to various forces. Different models have been developed to measure these forces and data comparing forces in healthy individuals with OSA patients are rare. PURPOSE: Purpose of the study was to evaluate possible differences in tongue forces between healthy individuals and patients with OSA. METHOD: To evaluate maximum isometric tongue forces, we conducted a matched pair design study including 20 healthy individuals and 20 patients suffering from OSA. Maximum isometric tongue forces were measured in an anterior/posterior direction with the help of self-designed new device that clamps the tongue. RESULTS: We could show that the maximum isometric force does not differ significantly in healthy individuals (10.7 ± 5.2N) from patients with OSA (14.4 ± 6.3N). CONCLUSION: Currently there are no indications that maximum isometric tongue force does differ in healthy individuals and patients with OSA. Higher, as well as lower, tongue forces in patients with OSA seem not to differ from healthy subjects and therefore may not be needed to consider, in the development of tongue management devices, for OSA patients.

[Conservative treatment of obstructive sleep apnea using non-PAP therapies]. / Konservative Therapie der obstruktiven Schlafapnoe mit Nicht-PAP-Verfahren.

In Germany about one third of adults aged between 30 and 69 years suffer from obstructive sleep apnea (OSA). Snoring, inspiratory flow limitations, hypopneas, and apneas occur, leading to disturbed sleep, reduced daytime performance, and increased cardiovascular morbidity and mortality. Positive airway pressure therapy (PAP therapy) can be successfully administered in every OSA severity. However, other conservative treatments have to be considered for some patients, particularly in PAP failure or intolerance. The individual treatment concept is based on poly(somno)graphic, morphological, and functional assessment, taking treatment acceptance, adherence, and compliance into account.

Upper Airway Stimulation versus Untreated Comparators in Positive Airway Pressure Treatment-Refractory Obstructive Sleep Apnea.

Rationale: Understand the impact of insurance coverage on sleep apnea outcomes for patients awaiting upper airway stimulation.Objectives: Examine the natural history of impact of upper airway stimulation treatment versus insurance denial (comparators) on sleep apnea outcomes.Methods: A parallel-arm experimental study design was used to compare objective sleep apnea measures and patient-reported outcomes in those who received upper airway stimulation approval versus denial in a multinational prospective study (NCT02907398). Wilcoxon rank-sum test and logistic regression models were used to assess for differences of objective and subjective outcome changes in those who underwent upper airway stimulation versus no treatment comparators.Results: A greater reduction in apnea-hypopnea index was observed in those who underwent upper airway stimulation (n = 230, follow-up: 360 ± 171 d) versus no treatment (n = 100, follow-up: 272 ± 278 d), that is, -19.1 ± 15.8 versus -8.1 ± 20.9, respectively, P < 0.001, with consistent findings observed with nocturnal hypoxia measures. Concordantly, a greater improvement noted with subjective measures of dozing propensity was observed in patients undergoing upper airway stimulation versus comparators (Epworth Score, -5.1 ± 5.5 vs. 1.8 ± 3.7, respectively, P < 0.001) and overall sleep-related patient-reported outcomes. Women and those with previous oral appliance use had a lower odds of insurance approval (odds ratio [OR], 0.40; 95% confidence interval [95% CI], 0.22-0.71 and OR, 0.35; 95% CI, 0.18-0.69, respectively).Conclusions: Objective and subjective sleep apnea burden was more improved in those receiving upper airway stimulation versus not. Results underscore the need to optimize clinical care pathways focused on effective treatment of patients with obstructive sleep apnea who are not upper airway stimulation-insurance eligible and prioritize public health policy initiatives to address insurance-based sex-specific disparities.

Reflex swallowing elicited by electrical stimulation in obstructive sleep apnea patients: A preliminary study.

This study tested whether electrical stimulation of the pharyngeal mucosa is able to induce reliably the swallowing reflex in awake and asleep obstructive sleep apnea (OSA) patients, and whether the induced reflexes affect the sleep variables. In addition, the latency, occurrence, and morphology of swallows were evaluated. Eight patients received an esophageal catheter that was used on three consecutive nights for electrical stimulation and manometric recordings. The electrical stimulation proved itself safe, but its efficiency in inducing swallows sank from 80.0 % in awake to 37.4 % in sleeping subjects and was lowest in the sleep stage N3. The swallowing reflex was triggered with a mean latency of 3.69 ± 0.70 s, was predominantly induced in the hyperventilation phase, and had no significant effect on the subject's sleep variables. These findings indicate that electrical stimulation can more effectively trigger the swallowing reflex while the subjects are awake than during sleep without showing remarkable clinical benefits in terms of apnea-hypopnea index (AHI) improvement.

Long-term follow-up of the German post-market study for upper airway stimulation for obstructive sleep apnea.

PURPOSE: Upper airway stimulation (UAS) is an effective treatment for obstructive sleep apnea (OSA) in positive airway pressure (PAP) failure. Most reports have presented short-term data, so long-term safety and efficacy reports are rare. The German post-market study (G-PMS) has followed approximately 60 patients from three implanting centers for several years. METHODS: Patients with OSA and PAP failure qualified for the G-PMS by the absence of obesity class 2 an AHI between 15 and 65 events/h and absence of complete concentric collapse at the velum during drug-induced sleep endoscopy. Optional 2- and 3-year follow-ups after implantation were collected during routine clinical practice. We measured respiratory parameters such as apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) and daytime sleepiness using the Epworth sleepiness scale (ESS) in a per protocol analysis. Usage was calculated from device-downloaded reports. Device-related complications were documented. RESULTS: Of the 60 original patients, 41 returned for 2-year follow-up, and 38 for 3 years. About 76% at 2 years and 68% at 3 years met the criterion of therapy success defined as an AHI below 15/h. The median AHI was reduced from 28.6/h (baseline) to 9.0/h (2 years) and 10.0/h (3 years); whereas median ODI decreased from 27.0 to 6.3/h (2 years), and 8.3/h (3 years). Median ESS improved from baseline 13 points to 4 (2 years) and 6 (3 years). Usage was stable at approximately 45 h per week at 2 and 3 years. Serious device-related adverse events were rare, with two-device explantation between 12 to 36 months postoperatively. CONCLUSIONS: The German multi-center long-term outcomes compare favorably with previously published studies. Respiratory and sleepiness efficacy outcomes were sustained over 2 and 3 years, with a favorable safety profile, supporting the safety and efficacy of a chronic implantable therapy.

Previous Surgery and Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea.

OBJECTIVE: To examine whether previous palate or hypopharyngeal surgery was associated with efficacy of treatment of obstructive sleep apnea with hypoglossal nerve stimulation. STUDY DESIGN: Cohort (retrospective and prospective). SETTING: Eleven academic medical centers. SUBJECTS AND METHODS: Adults treated with hypoglossal nerve stimulation were enrolled in the ADHERE Registry. Outcomes were defined by the apnea-hypopnea index (AHI), in 3 ways: change in the AHI and 2 definitions of therapy response requiring ≥50% reduction in the AHI to a level <20 events/h (Response20) or 15 events/h (Response15). Previous palate and hypopharyngeal (tongue, epiglottis, or maxillofacial) procedures were documented. Linear and logistic regression examined the association between previous palate or hypopharyngeal surgery and outcomes, with adjustment for age, sex, and body mass index. RESULTS: The majority (73%, 217 of 299) had no previous palate or hypopharyngeal surgery, while 25% and 9% had previous palate or hypopharyngeal surgery, respectively, including 6% with previous palate and hypopharyngeal surgery. Baseline AHI (36.0 ± 15.6 events/h) decreased to 12.0 ± 13.3 at therapy titration (P < .001) and 11.4 ± 12.6 at final follow-up (P < .001). Any previous surgery, previous palate surgery, and previous hypopharyngeal surgery were not clearly associated with treatment response; for example, any previous surgery was associated with a 0.69 (95% CI: 0.37, 1.27) odds of response (Response20 measure) at therapy titration and a 0.55 (95% CI: 0.22, 1.34) odds of response (Response20 measure) at final follow-up. CONCLUSION: Previous upper airway surgery was not clearly associated with efficacy of hypoglossal nerve stimulation.

Therapy of bilateral vocal fold paralysis: Real world data of an international multi-center registry.

PURPOSE: To collect data on diagnosis, treatment, patient's management, and quality of life in patient with bilateral vocal fold paralysis (BVFP). METHODS: A retrospective, observational, multicenter registry study was performed. Medical records of 326 adults with permanent BVFP (median age: 61 years; 70% female, 60% after thyroid surgery) generated between 2010 and 2017. RESULTS: Median time between BVFP onset and inclusion was 1.2 years. Median post-treatment follow-up was 2 months (range: 0-42). Surgery was treatment of choice in 61.7% of the cases, with a 2-year revision rate of 32.4%. Prior to inclusion, 40.2% of the patients underwent at least one surgery. For tracheotomized patients, decannulation rate was 33.8%. Non-surgical treatments included voice therapy and botulinum toxin injection. Corticosteroid application was the most frequent treatment for post-treatment complications (18%; 1-month after surgery). Older age was an independent predictor for dyspnea (Hazard ratio [HR] = 1.041; CI = 1.005 to 1.079; p = 0.026) and the need for oxygen treatment (HR = 1.098; CI = 1.009 to 1.196; p = 0.031). Current alcohol consumption (HR = 2.565; CI = 1.232 to 5.342; p = 0.012) and a cancer-related etiology (HR = 4.767; CI = 1.615 to 14.067; p = 0.005) were independent factors of higher revision risk. CONCLUSIONS: Surgery for BVFP is currently not standardized but highly variable. Postoperative and BVFP-related complications and revision surgery are frequent. Complications are linked to patients' alcohol drinking habits and BVFP etiology. These results shall be confirmed by the upcoming evaluation of the prospective data of this registry.

Implantation of the nyxoah bilateral hypoglossal nerve stimulator for obstructive sleep apnea.

OBJECTIVES: This report describes the surgical implantation of a novel bilateral hypoglossal nerve stimulator (Genio system®, Nyxoah S.A., Belgium) and the successful treatment of a patient with moderate obstructive sleep apnea (OSA). STUDY DESIGN: Surgical technique description and case study report. METHODS: The bilateral implantable stimulator (IS) simultaneously stimulates both genioglossus (GG) muscles to reduce airway obstruction. At night, patients wear an activation chip under their chin that wirelessly transmits energy to the implant and enables the nerve stimulation. Surgical implantation of the IS is performed under general anesthesia by making a small incision above the hyoid bone and dissecting through the platysma, mylohyoid, and geniohyoid muscles to the GG muscle. The hypoglossal nerve branches are then identified, followed by suturing the IS in place. The system was evaluated in an otherwise healthy, 60-year-old woman with moderate OSA (apnea hypopnea index (AHI): 25/hr, nadir O2 saturation: 78%). Appropriate stimulation settings were determined at 2-, 3-, and 6-months post implantation during polysomnography (PSG) and changes in apnea and hypopnea events and oxygen desaturation recorded. RESULTS: The surgery was well tolerated by the patient with an uneventful recovery. The PSG at 6 months showed that AHI per hour, obstructive apnea events per hour, hypopnea events per hour, and oxygen desaturation index have been reduced by 88%, 92%, 88%, and 97%, respectively, and nadir O2 saturation improved to 91%. CONCLUSIONS: The absence of complications and considerable reduction of apnea and hypopnea events in this case study help demonstrate the potential safety and efficacy of the bilateral hypoglossal nerve stimulator. LEVEL OF EVIDENCE: 4.