Sleep Surgery in the Era of Precision Medicine

Genioplasty and Hyoid Advancement by Distraction Osteogenesis for the Correction of Obstructive Sleep Apnea in a Pediatric Patient

Advancement genioplasty is one variation of genioglossus advancement (GA) and GA is a surgical intervention that can be applied for obstructive sleep apnea (OSA) caused by hypopharyngeal collapse. The genioglossus muscle originates from the posterior surface of the midline mandible and inserts into the entire tongue mass and the body of the hyoid bone. Placing horizontal tension on the genioglossus muscle enlarges the posterior airway space. We use a modified GA that applies distraction osteogenesis to increase forward movement of the genioglossus muscle and also connects the bone transport segment to the hyoid bone with a thread to maximize the anterior movement of the hyoid bone. We used this technique on a young patient and obtained good results.

Maxillomandibular Advancement Efficacy in Obstructive Sleep Apnea Patients With Class 2 Versus 3 Dentofacial Deformity

OBJECTIVE

To compare the efficacy of maxillomandibular advancement (MMA) for patients with obstructive sleep apnea (OSA) with class 2 versus 3 dentofacial deformities (DFDs).

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary sleep surgery center.

METHODS

Patients with OSA and DFD class 2 versus 3 undergoing MMA at Stanford Sleep Surgery between 2014 and 2021 were matched by preoperative body mass index (BMI), age, and sex. Postoperative outcome was compared with polysomnography measures and patient-reported outcome measures (PROMs).

RESULTS

Twenty-eight matched subjects, 14 in each deformity group were identified and assessed. The mean age (standard deviation) was 34.29 (10.21) and 33.86 (10.23) for classes 2 and 3, respectively. The apnea-hypopnea index (AHI) decreased from 43.42 (28.30) to 9.6 (5.29) (p < .001) and 37.17 (35.77) to 11.81 (15.74) (p = .042) in class 2 and 3 subjects, respectively. The oxygen desaturation index (ODI) changed from 30.48 (24.02) to 6.88 (3.39) (p = .024) and 11.43 (11.40) to 5.44 (7.96) (p = .85) in class 2 and 3 subjects, respectively. The Epworth sleepiness scale changed from 8.93 (5.28) to 3.91 (2.70) (p = .018) and 10.23 (4.38) to 4.22 (3.07) (p = .006) in class 2 and 3 subjects, respectively.

CONCLUSION

Among age, sex, and BMI-matched subjects, MMA is equally effective in both dentofacial class 2 and 3 groups, both objectively and subjectively. Preoperatively, dentofacial class 2 patients with OSA presented with the more severe disease with higher AHI and ODI. Dentofacial class 3 patients with OSA may require additional attention to improve nasal function outcomes.

Association of Backscattered Ultrasonographic Imaging of the Tongue With Severity of Obstructive Sleep Apnea in Adults

Importance

Determining interventions to manage obstructive sleep apnea (OSA) depends on clinical examination, polysomnography (PSG) results, and imaging analysis. There remains the need of a noninvasive and cost-effective way to correlate relevant upper airway anatomy with severity of OSA to direct treatment and optimize outcome.

Objective

To determine whether backscattered ultrasonographic imaging (BUI) analysis of the tongue is associated with severity of OSA in adults.

Design, Setting, and Participants

In this prospective, single-center, diagnostic study of a consecutive series of patients (aged ≥18 years) at a sleep surgery clinic, the 89 included patients had a PSG within 3 years at the time of ultrasonography and BUI analysis between July 2020 and March 2022. Patients were excluded if body mass index had changed more than 10% since time of PSG. A standardized submental ultrasonographic scan with laser alignment was used with B-mode and BUI analysis applied to the tongue. The B-mode and BUI intensity were associated with the apnea-hypopnea index (AHI), a measure of severity of apnea from normal (no OSA) to severe OSA.

Exposures

Ultrasonography and PSG.

Main Outcomes and Measures

The main outcomes were BUI parameters and their association with AHI value.

Results

Eighty-nine patients were included between July 2020 and March 2022. A total of 70 (78.7%) male patients were included; and distribution by race and ethnicity was 46 (52%) White participants, 22 (25%) Asian participants, and 2 (2%) African American participants, and 19 (21%) others. Median (IQR) age was 37.0 (29.0-48.3) years; median (IQR) BMI was 25.3 (23.2-29.8); and median (IQR) AHI was 11.1 (5.6-23.1) events per hour. At the middle to posterior tongue region, the 4 OSA severity levels explained a significant portion of the BUI variance (η2 = 0.153-0.236), and a significant difference in BUI values was found between the subgroups with AHI values of less than 15 (no OSA and mild OSA) and greater than or equal to 15 (moderate OSA and severe OSA) events per hour. The echo intensity showed no significant differences. The BUI values showed a positive association with AHI, with a Spearman correlation coefficient of up to 0.43. Higher BUI values remained associated with higher AHI after correction for the covariates of BMI and age.

Conclusions and Relevance

In this prospective diagnostic study, standardized BUI analysis of the tongue was associated with OSA severity. With the practicality of ultrasonography, this analysis is pivotal in connecting anatomy with physiology in treatment planning for patients with OSA.

Patient's Perception of Nasal Function and Cosmesis After Maxillomandibular Advancement for Obstructive Sleep Apnea

Background: Maxillomandibular advancement (MMA) remains one of the most effective surgeries for the treatment of obstructive sleep apnea (OSA), but it can be difficult to manage nasal and midfacial esthetics for patients requiring significant maxillary advancement. Objective: To evaluate changes in the Standardized Cosmesis and Health Nasal Outcomes Survey (SCHNOS) after the modified MMA approach. Methods: This prospective study was conducted on subjects undergoing MMA at a tertiary referral center from September 2020 to August 2021. Nasal function, cosmesis, and sleepiness were assessed perioperatively with the SCHNOS, visual analog scale for nasal function and cosmesis, and Epworth sleepiness scale (ESS). Objective polysomnography data were also investigated. Results: Thirty-one subjects met inclusion criteria. After MMA, SCHNOS-O (obstruction domain) improved from 44.38 ± 26.21 to 19.03 ± -4.75 (p < 0.001). The SCHNOS-C (cosmesis domain) improved significantly from 13.95 ± 19.32 to 5.27 ± 8.93 (p = 0.029). Specific items evaluating self-esteem, nasal straightness, and symmetry showed significant improvement (p = 0.006, 0.025, 0.044). The ESS also improved from 9.41 ± 6.11 to 3.26 ± 3.03 (p < 0.001), and it correlated with nasal obstruction scores. Conclusion: In this study, patients' perception of nasal obstruction and appearance improved after applying the nasal modifications to MMA described for OSA.

Automatic scoring of drug-induced sleep endoscopy for obstructive sleep apnea using deep learning

BACKGROUND

Treatment of obstructive sleep apnea is crucial for long term health and reduced economic burden. For those considered for surgery, drug-induced sleep endoscopy (DISE) is a method to characterize location and pattern of sleep-related upper airway collapse. According to the VOTE classification system, four upper airway sites of collapse are characterized: velum (V), oropharynx (O), tongue (T), and epiglottis (E). The degree of obstruction per site is classified as 0 (no obstruction), 1 (partial obstruction), or 2 (complete obstruction). Here we propose a deep learning approach for automatic scoring of VOTE obstruction degrees from DISE videos.

METHODS

We included 281 DISE videos with varying durations (6 s-16 min) from two sleep clinics: Copenhagen University Hospital and Stanford University Hospital. Examinations were split into 5-s clips, each receiving annotations of 0, 1, 2, or X (site not visible) for each site (V, O, T, and E), which was used to train a deep learning model. Predicted VOTE obstruction degrees per examination was obtained by taking the highest predicted degree per site across 5-s clips, which was evaluated against VOTE degrees annotated by surgeons.

RESULTS

Mean F1 score of 70% was obtained across all DISE examinations (V: 85%, O: 72%, T: 57%, E: 65%). For each site, sensitivity was highest for degree 2 and lowest for degree 0. No bias in performance was observed between videos from different clinicians/hospitals.

CONCLUSIONS

This study demonstrates that automating scoring of DISE examinations show high validity and feasibility in degree of upper airway collapse.

Anatomical determinants of upper airway collapsibility in obstructive sleep apnea: A systematic review and meta-analysis

Upper airway (UA) collapsibility is one of the key factors that determine the severity of obstructive sleep apnea (OSA). Interventions for OSA are aimed at reducing UA collapsibility, but selecting the optimal alternative intervention for patients who fail CPAP is challenging because currently no validated method predicts how anatomical changes affect UA collapsibility. The gold standard objective measure of UA collapsibility is the pharyngeal critical pressure (P_crit). A systematic literature review and meta-analysis were performed to identify the anatomical factors with the strongest correlation with P_crit. A search using the PRISMA methodology was performed on PubMed for English language scientific papers that correlated P_crit to anatomic variables and OSA severity as measured by the apnea-hypopnea index (AHI). A total of 29 papers that matched eligibility criteria were included in the quantitative synthesis. The meta-analysis suggested that AHI has only a moderate correlation with P_crit (estimated Pearson correlation coefficient r = 0.46). The meta-analysis identified four key anatomical variables associated with UA collapsibility, namely hyoid position (r = 0.53), tongue volume (r = 0.51), pharyngeal length (r = 0.50), and waist circumference (r = 0.49). In the future, biomechanical models that quantify the relative importance of these anatomical factors in determining UA collapsibility may help identify the optimal intervention for each patient. Many anatomical and structural factors such as airspace cross-sectional areas, epiglottic collapse, and palatal prolapse have inadequate data and require further research.

Comparative Efficacy of Obstructive Sleep Apnea Patients Undergoing Multilevel Surgery Followed by Upper Airway Stimulation Versus Isolated Upper Airway Stimulation

PURPOSE

Upper Airway Stimulation (UAS) of the hypoglossal nerve is a rapidly growing management option for patients with obstructive sleep apnea (OSA). Our study compares the treatment efficacy of UAS between those who were initially ineligible for UAS but subsequently met eligibility after multilevel surgery versus those who underwent isolated UAS for the treatment of moderate to severe OSA.

METHODS

The investigators implemented a retrospective single-center cohort study of patients aged 18+ years who presented for surgical evaluation of OSA from 2016-2019 and underwent UAS implantation. The predictor variable was eligibility status for UAS. Initially ineligible subjects were defined as having an apnea-hypopnea (AHI) > 65 events/hr, body mass index (BMI) > 32 kg/m², or complete concentric collapse (CCC) on drug-induced sleep endoscopy. Eligible subjects were defined as having an AHI between 15 and 65, with no CCC on drug-induced sleep endoscopy. The primary outcome was change in AHI which was measured preoperatively and 6 months post UAS implantation. Secondary outcomes were change in Epworth sleepiness scale and Fatigue severity scale. Covariates were age, sex, and BMI. Data analysis involved descriptive statistics and multivariable statistical models; P < .05 was considered significant.

RESULTS

Thirty six patients underwent UAS implantation from 2016-2019. Eighteen patients who were initially ineligible for UAS underwent multilevel surgery, including uvulopalatopharyngoplasty, distraction osteogenesis maxillary expansion, or maxillomandibular advancement. Mean age was 62.4 ± 9 years and BMI of 29.1 ± 4 kg/m² with 5 female patients. The cohort of 17 patients who met criteria for UAS from the start had a mean age of 62.9 ± 14 years and mean BMI of 26.7 ± 4 kg/m² with 2 female patients. Mean AHI reduction for the multilevel group was 37.6 ± 21.2 events per hour (P < .001). Mean AHI reduction for the UAS-only group was 31.5 ± 13 events per hour (P < .001). When adjusted for age, BMI, and sex, the multilevel group had a more significant reduction (18 AHI events) compared to the isolated group (P < .001).

CONCLUSIONS

For patients who are ineligible for UAS due to severity of OSA or CCC of the velum, multilevel surgery including maxillomandibular advancement followed by UAS confers effective post-treatment results, which was superior to the UAS-only group.

Surgical anatomy of the lingual nerve for palate surgery: where is located and how to avoid it

PURPOSE

To describe the anatomic relationship of the lingual nerve with the lateral oropharyngeal structures.

METHODS

An anatomic dissection of the lateral oropharyngeal wall was conducted in eight sides from four fresh-frozen cadaveric heads. Small titanium clips were placed along the lingual nerve and the most anterior and medial border of the medial pterygoid muscle. Radiological reconstructions were employed for optimal visualization; the coronal view was preferred to resemble the surgical position. The distance between the lingual nerve and the medial pterygoid muscle at its upper and lower portion was measured radiologically. The trajectory angle of the lingual nerve with respect to the pterygomandibular raphe was obtained from the intersection between the vector generated between the clips connecting the upper and lower portion of the medial pterygoid muscle with the vector generated from the lingual nerve clips.

RESULTS

The mean distance from the upper portion of the medial pterygoid muscle and superior lingual nerve clips was 10.16 ± 2.18 mm (mean ± standard deviation), and the lower area of the medial pterygoid muscle to the lingual nerve was separated 5.05 ± 1.49 mm. The trajectory angle of the lingual nerve concerning to the vector that describes the upper portion of the most anterior and medial border of the medial pterygoid muscle with its lower part was 43.73º ± 11.29.

CONCLUSIONS

The lingual nerve runs lateral to the lateral oropharyngeal wall, from superiorly-inferiorly and laterally-medially, and it is closer to it at its lower third.

New method of Le Fort I osteotomy with increased stability

Backsliding is a major problem when moving the maxilla significantly forward in orthognathic surgery. For example, in sleep surgery, maxillomandibular advancement is an application of orthognathic surgery, and it is well known that the anterior movement of the maxilla back and forth is an important factor that greatly widens the pharyngeal airway. However, postoperative backsliding is a major problem in this surgery. Therefore, a surgical method was devised to prevent the maxilla from retracting by adjusting the bone when moving the maxilla forward.

A Novel Performance-Based Paradigm of Care for Cochlear Implant Follow-Up

OBJECTIVES

Utilize a multi-institutional outcomes database to determine expected performance for adult cochlear implant (CI) users. Estimate the percentage of patients who are high performers and achieve performance plateau.

STUDY DESIGN

Retrospective database study.

METHODS

Outcomes from 9,448 implantations were mined to identify 804 adult, unilateral recipients who had one preoperative and at least one postoperative consonant-nucleus-consonant (CNC) word score. Results were examined to determine percent-correct CNC word recognition preoperatively and at 1, 3, 6, 12, and 24 months after activation. Outcomes from 318 similar patients who also had at least three postoperative CNC word scores were examined. Linear mixed-effects regression was used to examine CNC word performance over time. The time when each patient achieved maximum performance was recorded as a surrogate for time of performance plateau. Patients were assigned as candidates for less intense follow-up if they were high performers and achieved performance plateau.

RESULTS

Among 804 patients with at least one postoperative score, CNC score improved at all time intervals. Average performance after the 3-month time interval was 47.2% to 51.5%, indicating a CNC ≥ 50% cutoff for high performers. Among 318 patients with at least three postoperative scores, performance improved from 1 to 3 (P = .001), 3 to 6 (P = .001), and 6 to 12 (P = .01) months. Scores from the 12- and 24-month intervals did not significantly differ (P = .09). By 12 months after activation, 59.7% of patients were considered candidates for less intense follow-up.

CONCLUSION

Findings suggest that CNC ≥ 50% is a reasonable cutoff to separate high performers from low performers. Within 12 months after activation, 59.7% of patients were good candidates for less intense follow-up.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

International Consensus Document on Obstructive Sleep Apnea

The main aim of this international consensus document on obstructive sleep apnea is to provide guidelines based on a critical analysis of the latest literature to help health professionals make the best decisions in the care of adult patients with this disease. The expert working group was formed primarily of 17 scientific societies and 56 specialists from a wide geographical area (including the participation of 4 international societies), an expert in methodology, and a documentalist from the Iberoamerican Cochrane Center. The document consists of a main section containing the most significant innovations and a series of online manuscripts that report the systematic literature searches performed for each section of the international consensus document. This document does not discuss pediatric patients or the management of patients receiving chronic non-invasive mechanical ventilation (these topics will be addressed in separate consensus documents).

The correlation of maxillomandibular advancement and airway volume change in obstructive sleep apnea using cone beam computed tomography

The purpose of this retrospective study was to evaluate the correlation of maxillomandibular advancement (MMA) and airway volume changes in patients with obstructive sleep apnea (OSA), and to determine the surgical skeletal movements necessary to achieve an increase in total airway volume (TAV) of ≥70%. Thirty patients with OSA treated by MMA were evaluated. Pre- and postoperative cone beam computed tomography images were used to determine the horizontal distance and angular changes in surgical parameters and linear, area, and volumetric airway parameters. Postoperatively, the horizontal distance of surgical parameters (A-point, UI, B-point, pogonion, and menton) and craniofacial angulation (SNA and SNB) increased significantly, similar to total surface area, TAV, and minimum cross-sectional area of the airway (p<0.0001). The total airway length decreased significantly (p<0.0001). The mean increase in TAV was 67.2%. There were positive correlations between linear surgical changes and the percentage change in TAV. All surgical parameters were predictive of a change in TAV ≥70%. The optimal surgical change was 6mm for A-point, 7.9mm for UI, 7.6mm for B-point, 11.2mm for pogonion, and 10mm for menton. In conclusion, maxillary advancement of less than 10mm was adequate in this study to obtain an increase in the TAV of at least 70%.

Does the Lack of Gender-Specific Apnea-Hypopnea Index Cutoff for Obstructive Sleep Apnea Impact Surgical Selection?

PURPOSE

The apnea-hypopnea index (AHI) is the parameter on which the severity of obstructive sleep apnea (OSA) is based and is also the determinant for both clinicians and third-party payers for surgical procedures. The purpose of this retrospective cross-sectional chart review is to examine differences in symptoms and AHI between men and women with OSA and whether this may impact timing and selection of surgical care.

METHODS

Retrospective cross-sectional study of patients aged 18 years and older who presented at a single center for surgical evaluation of OSA from January 2017 to 2020. AHI, oxygen desaturation index, respiratory disturbance index, and lowest oxygen saturation were obtained from polysomnography. The predictor variable was gender, and the outcome variable was AHI. Unadjusted and multivariate adjusted linear regression models were used to compare differences in AHI between gender, controlling for age, body mass index (BMI), Epworth sleepiness scale, and fatigue severity scale. Poisson regression analysis with robust error was used to assess the relative risks of antidepressant and anxiolytic medication use between genders.

RESULTS

A total of 408 consecutive new patients seen for surgical evaluation to treat OSA (248 men and 160 women) were included. Median patient age was 40 years for men and 41 years for women. Median AHI for men was 22.1 events per hour and 13.7 for women (P < .001). When adjusted for age and BMI, men have 33.2% higher AHI than women, with age contributing to 2% and BMI contributing to 6% of the difference. When controlling for age, BMI, Epworth sleepiness scale, and fatigue severity scale, women have a 2.2 increased relative risk of taking anxiolytic or antidepressant medications.

CONCLUSIONS

Women with OSA seeking surgery in a dedicated sleep practice have 33% lower AHI than men when controlling for age, BMI, and symptoms. Based on our findings, non-gender-specific AHI may handicap the surgeon from offering the full range of available procedures to women with OSA.

Maxillomandibular Advancement and Upper Airway Stimulation: Extrapharyngeal Surgery for Obstructive Sleep Apnea

There are many ways to categorize surgery for obstructive sleep apnea (OSA), one of which is to distinguish between intrapharyngeal and extrapharyngeal procedures. While the general otolaryngologist treating OSA is familiar with intrapharyngeal procedures, such as uvulopalatopharyngoplasty and tongue base reduction, extrapharyngeal sleep operations such as maxillomandibular advancement (MMA) and upper airway stimulation (UAS) have evolved rapidly in the recent decade and deserve a dedicated review. MMA and UAS have both shown predictable high success rates with low morbidity. Each approach has unique strengths and limitations, and for the most complex of OSA patients, the two in combination complement each other. Extrapharyngeal airway operations are critical for achieving favorable outcomes for sleep surgeons.

Upper airway stimulation as an alternative to maxillomandibular advancement for obstructive sleep apnoea in a patient with dentofacial deformity: case report with literature review

Obstructive sleep apnoea (OSA) is characterized by repeated upper airway collapse leading to oxygen desaturation resulting in cardiovascular and neurocognitive sequelae. Upper airway surgeries such as palatopharyngoplasty, tongue base surgery, and maxillomandibular advancement can improve patient tolerance of continuous positive airway pressure, quality of life, and the severity of OSA. Upper airway stimulation (UAS) of the hypoglossal nerve is a contemporary US Food and Drug Administration-approved treatment modality for OSA with a fundamentally different mechanism. We report the case of a 65-year-old male with a high body mass index, hypertension, diabetes, dentofacial deformity, and severe OSA. He presented with a respiratory distress index (RDI) of 89.1 events per hour, apnoea-hypopnoea index (AHI) of 82.7 events per hour, and minimum oxygen saturation of 75%. He chose to undergo UAS. Initially, complete concentric collapse of the velum was found during drug-induced sedation endoscopy, which was converted by palatopharyngoplasty to meet inclusion criteria for UAS. The patient achieved surgical cure with postoperative RDI and AHI of 2 events per hour with minimum oxygen saturation of 83%, and resolution of daytime somnolence. UAS is an effective surgical option to broaden the surgeon's ability to treat OSA, especially if facial skeletal surgery is contraindicated or declined by the patient with dentofacial deformity.