Hypoglossal Research Articles

Outcome Reporting in Prospective Studies Evaluating Neurostimulation for Obstructive Sleep Apnea.

Due to the controversy surrounding the appropriate outcomes in neurostimulation, we sought to systematically describe ways in which polysomnography and apnea-hypopnea index are reported in prospective studies involving unilateral hypoglossal nerve stimulation. MEDLINE (Ovid), Embase (Ovid), Cochrane Library, and Scopus. Following the Preferred Reporting items of Systematic Reviews and Meta-analysis (PRISMA) Statement guidelines, a systematic two-reviewer system was used for study screening and quality assessment. Articles that met inclusion criteria were included. Quality was evaluated with either the Newcastle-Ottawa Quality Assessment Scale or the Covidence risk-of-bias tool. Fifteen studies met the inclusion criteria, which included 14 prospective cohort studies and one randomized controlled trial. Titration polysomnography was the primary sleep study used to acquire data in five of the studies compared to only three studies employing exclusively non-titration polysomnography to report outcomes. Three studies compiled data from two or more sleep studies to report a single apnea-hypopnea index. Within the 15 studies, non-titration apnea-hypopnea index was the most reported type (five studies). Titration apnea-hypopnea index was used to report outcomes in one study. Five studies did not specify what type of apnea-hypopnea index was employed to report treatment effectiveness. The reported sleep studies and corresponding apnea-hypopnea indices were highly variable across the studies. Because of the high degree of heterogeneity, future research would benefit from consistent use of a standardized apnea-hypopnea index to report outcomes related to hypoglossal nerve stimulation. NA Laryngoscope, 134:4873-4881, 2024.

Predicting Therapeutic Response to Hypoglossal Nerve Stimulation Using Deep Learning.

To develop and validate machine learning (ML) and deep learning (DL) models using drug-induced sleep endoscopy (DISE) images to predict the therapeutic efficacy of hypoglossal nerve stimulator (HGNS) implantation. Patients who underwent DISE and subsequent HGNS implantation at a tertiary care referral center were included. Six DL models and five ML algorithms were trained on images from the base of tongue (BOT) and velopharynx (VP) from patients classified as responders or non-responders as defined by Sher's criteria (50% reduction in apnea-hypopnea index (AHI) and AHI < 15 events/h). Precision, recall, F1 score, and overall accuracy were evaluated as measures of performance. In total, 25,040 images from 127 patients were included, of which 16,515 (69.3%) were from responders and 8,262 (30.7%) from non-responders. Models trained on the VP dataset had greater overall accuracy when compared to BOT alone and combined VP and BOT image sets, suggesting that VP images contain discriminative features for identifying therapeutic efficacy. The VCG-16 DL model had the best overall performance on the VP image set with high training accuracy (0.833), F1 score (0.78), and recall (0.883). Among ML models, the logistic regression model had the greatest accuracy (0.685) and F1 score (0.813). Deep neural networks have potential to predict HGNS therapeutic efficacy using images from DISE, facilitating better patient selection for implantation. Development of multi-institutional data and image sets will allow for development of generalizable predictive models. NA Laryngoscope, 134:5210-5216, 2024.

Hypoglossal Nerve Stimulation Outcomes in Pediatric Trisomy 21 Patients with Overweight or Obesity.

To assess the impact of body mass index (BMI) on hypoglossal nerve stimulator (HNS) implantation outcomes in pediatric patients with Down syndrome (DS). We compare outcomes of HNS implantation when comparing children based on overweight or obese status. Retrospective cohort study of patients at a single tertiary pediatric hospital who underwent HNS implantation between 2022 and 2024. Patients with DS under 21 years of age at time of implantation were included. One child with Wolf-Hirschhorn syndrome was also included. The main outcome measured was reduction in apnea-hypopnea index (AHI). Twenty patients were implanted with HNS during the study period. Eleven patients were implanted with a BMI considered overweight and 8 patients with a BMI considered obese. No significant correlation was found between BMI percentile and AHI reduction (r = 0.06, p = 0.8). No significant differences were found between obese and non-obese groups for preoperative AHI, postoperative AHI, or AHI reduction. Both groups responded favorably to HNS therapy with AHI reduction of 83.8% in obese patients and 81.9% in non-obese patients. We demonstrate no difference in postoperative AHI outcomes when comparing patients with obesity defined as BMI >95th percentile compared to those without. 3 Laryngoscope, 2024.

Treatment Outcomes in Awake Endoscopy With Advanced Programming in Hypoglossal Nerve Stimulation.

Hypoglossal nerve stimulation (HNS) is a treatment option for patients with moderate-to-severe obstructive sleep apnea. In the post-implant period, awake endoscopy with advanced programming (AEAP) can be employed to improve apnea hypopnea index (AHI) reduction and/or patient comfort. This study describes response patterns to HNS after AEAP as well as patient-specific patterns in our patient population. Retrospective evaluation of 17 consecutive patients who underwent AEAP between June 2019 and December 2022. Post-AEAP AHIs were used to create 2 response groups, which facilitated analysis of patient-based characteristics. AHI reporting, deemed non-titration AHI (NT-AHI), is the whole-night AHI resulting from non-titration studies. Chi-squared, Pearson correlation coefficient, and independent samples t-test were used to determine significance deemed as P < .05. Fifteen of 17 patients (88.2%) presented for failed NT-AHI reduction, and 2/17 (11.8%) presented for comfort measures. Eleven patients (65%) showed an improvement in post-AEAP NT-AHI; 6 (35%) patients failed to improve. Four patients with either lateral wall collapse or concentric wall collapse at the tongue base failed to improve NT-AHI compared to a single patient who showed an improved NT-AHI (P = .017). Of the 2 patients who presented with discomfort, patient 1/2 demonstrated improvement in device usage, and patient 2/2 reported improved comfort while maintaining average device usage. AEAP is a powerful tool that offers the ability to identify settings conducive to increased therapy efficacy and improved treatment tolerability. Airway phenotypes are closely correlated with treatment efficacy, and as such, careful anatomical consideration of the upper airway must be performed when titrating therapy. Amongst the different treatment options for obstructive sleep apnea, hypoglossal nerve stimulation has been shown to be effective in positive-airway-pressure intolerant patients. This article explores response patterns to AEAP and highlights the importance of careful anatomical considerations of the upper airway. Level 3.

Adults with Down syndrome and obstructive sleep apnea treated with hypoglossal nerve stimulation.

To examine the feasibility, adherence to therapy, and efficacy of hypoglossal nerve stimulation (HGNS) in adults with Down syndrome (DS) with obstructive sleep apnea. Adults patients with DS who met criteria for hypoglossal nerve stimulation were prospectively enrolled. Objective adherence was extracted from a cloud-based compliance database. Pre-operative sleep studies were compared to follow-up testing performed no sooner than 3 months after device activation. Eleven adults with DS underwent implantation of HGNS between May 2021 and July 2024. Median age was 27 years old (interquartile range 26, 33), BMI 28.5kg/m2 (26.5, 32.4), 27% were female, and had severe OSA (apnea-hypopnea index (AHI) 40/hr, (28.4, 42.9)). All patients were successfully implanted on an outpatient basis with no post-operative complications or readmissions and activated on schedule at 1 month after surgery. Adherence data show nightly usage longer than 4 hours was 100% and 96% of nights and a median of 9.2 and 8.5 hours/night in the first 30 and 90 days, respectively. Seven patients have undergone follow up testing and the median entire night AHI was reduced by 76%. All patients experienced a >50% decrease in AHI and to less than 15/hr. Median time spent below 88% improved from 2.0% (0.3,5.0) to 0.2% (0,0.6), and oxygenation nadir improved from 79.0% (75.5,85) to 88.0% (86.5,91). In this small initial cohort, HGNS appears to be a safe, well-tolerated and efficacious treatment option for adults with DS with moderate-severe obstructive sleep apnea and positive airway pressure therapy intolerance.

The five faces of flow in asynchronous hypoglossal nerve stimulation.

The five faces of flow in asynchronous hypoglossal nerve stimulation.

A PhD completed. Issues related to indication, surgery, and outcome of maxillomandibular advancement in obstructive sleep apnea

Obstructive sleep apnea is a common sleep-related breathing disorder. Although maxillomandibular advancement is widely recognized for its proven effectiveness, there are still uncertainties surrounding this procedure. This research therefore focused on the indication, surgical techniques, and outcomes of maxillomandibular advancement in patients with obstructive sleep apnea. A systematic review and meta-analysis showed that maxillomandibular advancement is more effective than multilevel surgery for the treatment of obstructive sleep apnea. Both maxillomandibular advancement and hypoglossal nerve stimulation were identified as effective and safe treatment methods for obstructive sleep apnea. Various retrospective studies also indicated that patients with hypopnea-dominant obstructive sleep apnea are better candidates for maxillomandibular advancement, in contrast to patients with cardiovascular diseases or a higher central apnea index. Furthermore, it was demonstrated that maxillomandibular advancement is effective in patients with a high percentage of central and mixed apneas, despite the potential surgical inaccuracies of maxillomandibular advancement, highlighting the broad applicability of this treatment method.

The impact of neck circumference on hypoglossal nerve stimulator therapy outcomes.

Hypoglossal nerve stimulation (HGNS) therapy has historically had strict eligibility requirements including a body mass index (BMI) < 32 kg/m2. However, recent Food and Drug Administration approval expanded indications to a BMI < 40 kg/m2. There is a wide variability in body fat distribution. This study sought to determine whether neck circumference (NC) is a better surrogate predictive variable for HGNS outcomes than BMI. A retrospective chart review was conducted at a tertiary care center on adults who underwent HGNS implantation by a single surgeon from March 2017 to October 2021. Baseline demographic data including NC, diagnostic sleep studies, and postimplantation HGNS titration studies were collected. Linear regression and Spearman's correlation coefficient analysis were used to compare NC, percentage of predicted NC, and BMI with the apnea-hypopnea index at effective voltage. This study included 43 patients who were middle-aged (61.1 years), predominantly male (76.7%), with severe obstructive sleep apnea (median apnea-hypopnea index, 35 events/h) and mean NC of 15.3 inches. Using the NC and percentage of predicted NC, positive correlations with apnea-hypopnea index at effective voltage were observed (P = .0033, Spearman's correlation coefficient = .438 and P = .0029, Spearman's correlation coefficient = .444). While controlling for BMI, a 1-inch increase in NC was associated with a 35% increase in apnea-hypopnea index at effective voltage (P = .0411). A larger NC was independently associated with worse HGNS outcomes. Further research is needed to support and confirm these findings, particularly across sexes. Hutz MJ, Plata DM, LoSavio P, Herdegen J, Zhang Y, Mokhlesi B. The impact of neck circumference on hypoglossal nerve stimulator therapy outcomes. J Clin Sleep Med. 2024;20(11):1755-1761.

Olfactory and trigeminal routes of HSV-1 CNS infection with regional microglial heterogeneity.

Herpes simplex virus type 1 (HSV-1) primarily targets the oral and nasal epithelia before establishing latency in the trigeminal ganglion (TG) and other peripheral ganglia. HSV-1 can also infect and become latent in the central nervous system (CNS) independent of latency in the TGs. Recent studies suggest entry to the CNS via two distinct routes: the TG-brainstem connection and olfactory nerve; however, to date, there is no characterization of brain regions targeted during HSV-1 primary infection. Furthermore, the immune response by microglia may also contribute to the heterogeneity between different brain regions. However, the response to HSV-1 by microglia has not been characterized in a region-specific manner. This study investigated the time course of HSV-1 spread within the olfactory epithelium (OE) and CNS following intranasal inoculation and the corresponding macrophage/microglial response in a C57BL/6 mouse model. We found an apical to basal spread of HSV-1 within the OE and underlying tissue accompanied by an inflammatory response of macrophages. OE infection was followed by infection of a small subset of brain regions targeted by the TG in the brainstem and other cranial nerve nuclei, including the vagus and hypoglossal nerve. Furthermore, other brain regions were positive for HSV-1 antigens, such as the locus coeruleus (LC), raphe nucleus (RaN), and hypothalamus while sparing the hippocampus and cortex. Within each brain region, microglia activation also varied widely. These findings provide critical insights into the region-specific dissemination of HSV-1 within the CNS, elucidating potential mechanisms linking viral infection to neurological and neurodegenerative diseases.IMPORTANCEThis study shows how herpes simplex virus type 1 (HSV-1) spreads within the brain after infecting the nasal passages. Our data reveal the distinct pattern of HSV-1 through the brain during a non-encephalitic infection. Furthermore, microglial activation was also temporally and spatially specific, with some regions of the brain having sustained microglial activation even in the absence of viral antigens. Previous reports have identified specific brain regions found to be positive for HSV-1 infection; however, to date, there has not been a concise investigation of the anatomical spread of HSV-1 and the brain regions consistently vulnerable to viral entry and spread. Understanding these region-specific differences in infection and immune response is crucial because it links HSV-1 infection to potential triggers for neurological and neurodegenerative diseases.

Diagnosis and Management of Obstructive Sleep Apnea: Updates and Review

Obstructive sleep apnea (OSA) is a heterogenous disease process that cannot be adequately categorized by AHI alone. There is a significant prevalence of OSA in the general population with ongoing efforts to evaluate the risk factors contributing to OSA and its associated clinical implications. Only by improving our understanding of OSA can we advance our methods in the diagnosis and treatment of OSA. For this article, the authors reviewed keywords of obstructive sleep apnea diagnosis and therapy in the databases of Embase, Medline, and Medline ePub over the past 3 years, excluding any articles that only addressed sleep apnea in children under age 17 years. This review article is divided into three main sections. First, we will investigate the use of novel screening tools, biomarkers, anthropometric measurements, and novel wearable technologies that show promise in improving the diagnosis of OSA. There is mention of comorbid conditions seen in OSA patients since certain disease combinations can significantly worsen health and should raise our awareness to diagnose and manage those concomitant disorders. The second section will look at the current and developing treatment options for OSA. These include positive airway therapy (PAP), mandibular advancement device (MAD), exciting new findings in certain medications, orofacial myofunctional therapy (OMT), hypoglossal nerve stimulation therapy (HGNS), and other surgical options. We will conclude with a section reviewing the current Clinical Practice Guidelines for Diagnostic Testing in Adults with Obstructive Sleep Apnea from 2017, which strongly advises polysomnography (PSG) or home sleep apnea testing (HSAT), along with comprehensive sleep evaluation for uncomplicated patients with a clinical presentation of OSA.

Cost-Effectiveness of Hypoglossal Nerve Stimulation for Pediatric Severe Obstructive Sleep Apnea in Down Syndrome Patients.

To examine the cost-effectiveness of hypoglossal nerve stimulation (HGNS) implantation at an early age in simulated pediatric cohorts with Down Syndrome (DS) and severe obstructive sleep apnea (OSA). Cost-utility analysis. Hypothetical cohort. A Markov model simulated 3 pediatric cohorts with DS and OSA beginning at age 4 years until 21 years. Cohorts received HGNS implants in early childhood, late childhood, or adulthood at age 4, 13 (current FDA-approved age), or 18 years, respectively. Input model parameters were obtained from the literature and our institution. Outcomes were measured with an incremental cost-effectiveness ratio (ICER), measured in dollars per quality-adjusted life-year (QALY). Deterministic 1-way sensitivity analyses were conducted to evaluate the effects of parameter uncertainty. Results (total costs; total QALYs) across the time horizon were determined for each cohort: early implantation ($83,300.35; 15.79), late ($48,319.09; 14.98), and adult ($38,721.07; 14.55). ICERs were $48,892.47 per QALY for early vs late implantation, $43,471.15 per QALY for early vs adult implantation, and $30,959.58 per QALY for late vs adult implantation. All ICERs were below a willingness-to-pay threshold of $50,000 per QALY. Varying the discount rate and utility expectedly varied the ICERs and cost-effectiveness. Threshold analysis showed early implantation to be cost-effective for a HGNS implantation cost up to $62,230 compared to late implantation. The current study suggests HGNS is a cost-effective treatment strategy for pediatric patients with DS and severe OSA. Our findings also suggest cost-effectiveness at ages younger than 13, the current age of FDA approval.

Hypoglossal nerve stimulation explantation in patients with obstructive sleep apnea - a systematic review.

Hypoglossal nerve stimulation explantation in patients with obstructive sleep apnea - a systematic review.

An Easy Way of Identification and Protection of the Hypoglossal Nerve during Neck Dissection for Head and Neck Cancer

Understanding the anatomical relationship between the Hypoglossal Nerve (HN) and the Facial Vein (FV) is crucial during neck dissections for head and neck cancer. The consistent placement of the HN beneath the FV provides a reliable anatomical landmark, aiding in the preservation of nerve function and reducing surgical complications. This paper reviews the anatomical pathway of the HN, its clinical implications, and surgical observations from 87 cases. Techniques for protecting the HN during neck dissection are also discussed, emphasizing the importance of precise surgical planning to avoid postoperative complications.

Upper Airway Stimulation for Children and Adolescents with Down Syndrome: Long-Term Follow-Up.

Hypoglossal nerve stimulation (HGNS) is safe and effective for patients with Down syndrome (DS) and severe persistent obstructive sleep apnea (OSA). Long-term outcomes for this patient population have not been evaluated. A prospective single-group multicenter cohort study with 1-year follow-up was conducted between 2015 and 2021 among 42 adolescent patients with DS and severe persistent OSA. Here, we evaluate long-term outcomes in this patient cohort. Patients were evaluated with polysomnogram (PSG) at three timepoints: pre-implantation (timepoint 1), 1-year post-implantation (timepoint 2), and long-term follow-up (timepoint 3). Long-term follow-up data were available for 33 of 42 patients. Mean (SD) of timepoint 3 was 4.0 (1.9) years after implantation. Using a therapy response definition of a 50% decrease in Apnea Hypopnea INdez (AHI) from timepoint 1, the response rate was 69.7% (23/33) at timepoint 2 and 87.9% (29/33) at timepoint 3. From timepoint 1, there was a mean (SD) decrease in AHI of 12.7 (13.4) events/h at timepoint 2 and 15.7 (13.1) events/h at timepoint 3. The mean percentage change in AHI between timepoints 1 and 2 was -51.1% (95% CI: -32.8% to -69.3%) and between timepoints 1 and 3 was -59.6% (95% CI: -42.0% to -77.3%). Patients with DS and severe persistent OSA who undergo HGNS implantation may continue to experience improvement in PSG parameters at long-term follow-up. Future studies are needed to assess additional long-term outcomes in this patient population, including neurocognition and quality of life. 3 Laryngoscope, 2024.

7357 Microscopic Papillary Thyroid Cancer Presenting with Cranial Nerve Palsies due to Metastatic Cervical Lymphadenopathy: A Case Report

Abstract Disclosure: N.N. Mukhtar: None. C. Zuo: None. B.R. Haugen: None. Introduction: Tumors metastasizing to head and neck are considered a rare cause of cranial nerve palsy (CNP). In this report, we describe an unusual presentation of metastatic microscopic follicular variant papillary thyroid cancer (FVPTC) presenting with CNP. Case Summary: A 68-year-old previously healthy female presented to her primary care physician with a 6-week history of difficulty speaking and chewing food. She did not notice any dysphagia, change in voice or shortness of breath. Cranial nerve examination was evident for palatal asymmetry, left-sided uvular and right-sided tongue deviations suggesting right glossopharyngeal and hypoglossal nerve palsies. Neck examination revealed a normal thyroid gland without palpable nodules however, the patient had multiple enlarged painless right cervical lymph nodes (CLN). MRI of the brain was normal. CT of the neck and chest showed enlarged, calcified right level II and III CLN (largest 4x3.5 cm) compressing the right internal jugular vein. In addition, bilateral pulmonary nodules (largest 1.7x1.5 cm) suspicious for metastasis were seen. CT-guided biopsy of left upper lobe lung nodule was consistent with metastatic thyroid cancer (positive PAX-8 and TTF-1 immunostaining). Neck ultrasound did not show any thyroid nodules, but did confirm 4 enlarged right CLN (largest 2.9 cm). The patient was referred to our multidisciplinary clinic for further evaluation. Based on the duration of her symptoms (6 weeks), her CNP was most-likely irreversible and agreement to proceed with total thyroidectomy, central and right lateral neck dissection aiming for complete resection in preparation for future treatment with radioactive iodine. Preoperative thyroglobulin level was 30.7 ng/ml (1.6-50), thyroglobulin antibody 24 U/mL (&amp;lt;40) and TSH 0.6 mIU/L (0.4-4.6). Intra-operatively; the patient had extensive, bulky lymphadenopathy extending to surrounding neck muscles and completely encasing right jugular vein. Histopathological examination of the resected tissue showed a unifocal right thyroid lobe microscopic (6x4x3 mm) infiltrative follicular variant papillary thyroid cancer (FVPTC). No extrathyroidal extension, necrosis, angioinvasion or lymphatic invasion were identified. Mitotic index was 3/ 2mm2. 13 out of 36 lymph nodes were positive for metastatic thyroid cancer (3/3 level II, 2/17 level III, 8/16 level IV), largest was 4.6 cm with extra-nodal extension. The patient was discharged on suppressive dose levothyroxine. Molecular studies: Next generation sequencing of the lung biopsy was negative for BRAFV[6]00E mutation and further molecular analyses are ongoing. Conclusion: This case describes two unique presentations of thyroid cancer; a microscopic FVPTC associated with large lateral cervical lymph node metastasis and, CNP as the initial presentation of thyroid cancer which to our knowledge, has not been reported previously. Presentation: 6/2/2024

Craniovertebral Junction Tuberculosis, a Rare Presentation With Hypoglossal and Facial Nerve Palsy

Case: A 47-year-old man presented with neck pain, restricted neck movements, along with involvement of facial and hypoglossal nerve. On the basis of clinico-radiological correlation, the patient was diagnosed with craniovertebral junction tuberculosis and was started on antitubercular therapy (ATT). Failing the conservative trial, the patient was operated and occipitocervical fusion was done with bone grafting. After 12 months of ATT intake, he showed complete recovery of the facial and hypoglossal nerve, with complete resolution of instability pain. Conclusion: Craniovertebral junction tuberculosis is uncommon, and its manifestation with cranial nerves involvement is even more rare. Meticulous clinico-radiological assessment should be done to diagnose and plan the treatment. Early recognition and prompt initiation of ATT, along with timely surgical intervention, when necessary, are crucial for optimal management and outcomes.

Implementing a Streamlined Hypoglossal Nerve Stimulator Pathway: Cost, Time to Surgery, and Outcomes.

To evaluate the costs, time to surgery, and clinical outcomes associated with implementing a streamlined hypoglossal nerve stimulator (HGNS) implantation pathway. Retrospective cohort study. Single tertiary care center in the United States from 2016 to 2023. Patients with a lack of complete concentric collapse of the velum during volitional snore on in-office laryngoscopy qualified for the streamlined HGNS pathway. This pathway consisted of confirmatory drug-induced sleep endoscopy (DISE) followed immediately by HGNS implantation during the same surgical encounter. Outcomes were compared to patients in the traditional pathway (standalone DISE followed by HGNS implantation on a later date). A total of 68 patients (13 streamlined, 55 traditional) with obstructive sleep apnea who underwent HGNS implantation were included. Patients were predominately male (70.6%) and White (95.6%) and had a mean (SD) age of 63.5 (10.0) years. The streamlined pathway was associated with a significant reduction in both hospital costs (mean difference $9258, 95% confidence interval [CI]: 3690-14,825; P = .002) and time to surgery (mean decrease of 3.82 months, 95% CI: 0.83-6.80 months; P = .013) compared to the traditional pathway. Patients in both groups had reduction in apnea-hypopnea index and Epworth Sleepiness Scale score, with no significant differences in comparisons between groups. In select patients, the streamlined HGNS pathway may expedite time to surgery and reduce hospital costs with comparable clinical outcomes to a traditional 2-stage pathway. Further research is warranted to validate patient selection and better understand longitudinal outcomes.

Comprehensive Analysis of Garcin Syndrome: A Systematic Review of the Etiology, Diagnosis, and Treatment.

Garcin syndrome is a rare neurological condition characterized by progressive unilateral involvement of multiple cranial nerves, without typical intracranial hypertension. It is often linked with aggressive malignancies and invasive infections; hence, it presents significant diagnostic and therapeutic challenges. Despite the advances in medical technology, the prognosis still remains poor, and there is limited literature on comprehensive reviews regarding its etiology, diagnosis, and management. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-based systematic review was performed in order to compile updated evidence related to Garcin syndrome. The PubMed and Scopus databases were comprehensively searched using the search terms "Garcin syndrome" AND ("etiology" OR "diagnosis" OR "treatment" OR "management"). Information was obtained from case reports and focused on common etiologies, clinical presentations, diagnostic methodologies, treatment protocols, and outcomes. The review discussed very diverse etiologies of Garcin syndrome. The most common among these were skull base tumors, metastatic lesions, and invasive infections like mucormycosis. Most of these were multiple cranial nerve (CN) involvements in which CN V (trigeminal nerve), CN VII (facial nerve), or CN XII (hypoglossal nerve) involvement was common. Advanced imaging, especially MRI, played a very crucial role in diagnosis, showing the presence of extensive bony destruction with the involvement of cranial nerves. Treatment was varied according to the etiology, ranging from chemotherapy and radiotherapy in neoplastic cases to active surgical intervention supported by antifungal therapy in infected cases. Garcin syndrome is a clinical challenge due to its diverse etiologies and complex management profile. While early diagnosis and intervention are emphasized, the prognosis remains grave, especially in cases presenting with metastatic disease or immunocompromised states. Future research should focus on better, more sensitive diagnostic modalities and the investigation of newer therapeutic approaches for Garcin syndrome patients.

The Emerging Role of Pharmacotherapy in Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is a prevalent pathology with current modalities of treatment including continuous positive airway pressure (CPAP), surgery, weight loss, hypoglossal nerve stimulation, and pharmacotherapy. While CPAP is the current standard treatment for OSA, lack of tolerance and side effects necessitate alternative modalities of treatment. Various pharmacologic agents exist with mechanisms that may target OSA. Early trials have demonstrated efficacy of noradrenergic-antimuscarinic combinations to stimulate the airway, promote pharyngeal muscle tone, and prevent airway collapse. These agents, which we discuss in detail, have demonstrated significant reductions in apnea-hypopnea index (AHI) and lowest oxygen saturations based on preliminary studies. Glucagon-like peptide 1 receptor agonists (GLP-1RA), which stimulate endogenous insulin, reducing glucagon release, and decreasing gastric emptying, have shown positive results for OSA patients through weight loss with reductions in AHI. In this narrative review article, we highlight the mechanisms, current data, and future potential for multiple drug classes, including respiratory stimulants and GLP-1RAs.

Baseline Characteristics Associated with Hypoglossal Nerve Stimulation Treatment Outcomes in Patients with Obstructive Sleep Apnea: A Systematic Review.

Hypoglossal nerve stimulation (HGNS) has emerged as an effective treatment for obstructive sleep apnea (OSA). Identifying baseline characteristics that prospectively could predict treatment outcomes even better is crucial for optimizing patient selection and improving therapeutic success in the future. A systematic review was conducted following PRISMA guidelines. Literature searches in Medline, Web of Science, and Cochrane databases identified studies assessing baseline characteristics associated with HGNS treatment outcomes. Inclusion criteria focused on studies with adult patients diagnosed with OSA, treated with HGNS, and assessed using full-night efficacy sleep studies. Risk of bias was evaluated using the NICE tool. Twenty-six studies met the inclusion criteria. Commonly reported baseline characteristics with predictive potential included BMI, site of collapse, and various pathophysiological endotypes. Most studies used the original Sher criteria to define treatment response, though variations were noted. Results suggested that lower BMI, absence of complete concentric collapse at the palatal level, and specific pathophysiological traits were associated with better HGNS outcomes. This review identified several baseline characteristics associated with HGNS outcomes, which may guide future patient selection. Importantly, patients were already preselected for HGNS. Standardizing response criteria is recommended to enhance the evaluation and effectiveness of HGNS therapy in OSA patients.