[Hyoid epiglottis combined with sternocleidomastoid muscle clavicle flap for repairing laryngeal defect after laryngeal trauma infection: a case report].

The initial treatment of open laryngeal trauma must be implemented immediately, with the primary focus on saving lives. However, in the later stages, various factors may cause changes in the structure and function of the larynx, which requires special attention. This article reports on the treatment process of a patient with depression who suffered from laryngeal trauma. Due to the late stage of laryngeal infection causing laryngeal defects, a hyoid epiglottis combined with sternocleidomastoid muscle clavicular flap repair was performed. Additionally, personalized functional exercise was performed, ultimately resulting in recovery.

Morphometry of the thyroid cartilage, epiglottis and piriform sinus: An anatomical study.

Background: The goal was to measure the piriform sinus, epiglottis, and thyroid cartilage in our sample population. Methods: This study included 22 adult embalmed cadavers available in the Department of Anatomy. Dimensions were measured using a digital Vernier caliper. Results: The mean height of the thyroid laminae was 27 ± 1.4 mm at the right side and 25.5 ± 1.4 mm at the left side. Mean width of the thyroid lamina was 27.1 ± 1.3 mm at the right side and 27.4 ± 0.9 mm at the left side. The mean thickness of thyroid cartilage was found to be 4.4 ± 0.4 mm and 3.9 ± 0.5 mm over the right and left sides. The mean length, width and thickness of the epiglottis were 29.1 ± 0.5 mm, 22.2 ± 0.6 mm and 2.6 ± 0.3 mm correspondingly. The height, width and thickness of the right piriform sinus were 25 ± 0.5 mm, 14.2 ± 0.5 mm and 12.6 ± 0.5 mm, the same parameters were 25.3 ± 1.3 mm, 15.1 ± 0.7 mm and 13.3 ± 0.4 mm for the left side. Conclusions: The height and thickness of the thyroid cartilage were greater on the right side than on the left side (p<0.05). It was statistically observed that the width and thickness were greater on the left side than on the right side (p < 0.05). The data about the height, width and thickness of the thyroid cartilage, epiglottis and piriform sinus are essential during the laryngeal and other neck surgeries. They guide in the preoperative positioning, predicting the difficulty of intraoperative exposure and retractor pulling.

Oropharyngeal swallowing hydrodynamics of thin and mildly thick liquids in an anatomically accurate throat-epiglottis model.

Understanding the mechanisms underlying dysphagia is crucial in devising effective, etiology-centered interventions. However, current clinical assessment and treatment of dysphagia are still more symptom-focused due to our limited understanding of the sophisticated symptom-etiology associations causing swallowing disorders. This study aimed to elucidate the mechanisms giving rise to penetration flows into the laryngeal vestibule that results in aspirations with varying symptoms. Methods: Anatomically accurate, transparent throat models were prepared with a 45° down flapped epiglottis to simulate the instant of laryngeal closure during swallowing. Fluid bolus dynamics were visualized with fluorescent dye from lateral, rear, front, and endoscopic directions to capture key hydrodynamic features leading to aspiration. Three influencing factors, fluid consistency, liquid dispensing site, and dispensing speed, were systemically evaluated on their roles in liquid aspirations. Results: Three aspiration mechanisms were identified, with liquid bolus entering the airway through (a) the interarytenoid notch (notch overflow), (b) cuneiform tubercle recesses (recess overflow), and (c) off-edge flow underneath the epiglottis (off-edge capillary flow). Of the three factors considered, liquid viscosity has the most significant impact on aspiration rate, followed by the liquid dispensing site and the dispensing speed. Water had one order of magnitude higher aspiration risks than 1% w/v methyl cellulose solution, a mildly thick liquid. Anterior dispensing had higher chances for aspiration than posterior oropharyngeal dispensing for both liquids and dispensing speeds considered. The effects of dispending speed varied. A lower speed increased aspiration for anterior-dispensed liquids due to increased off-edge capillary flows, while it significantly reduced aspiration for posterior-dispensed liquids due to reduced notch overflows. Visualizing swallowing hydrodynamics from multiple orientations facilitates detailed site-specific inspections of aspiration mechanisms.

Polysomnographic airflow shapes and site of collapse during drug-induced sleep endoscopy.

BACKGROUND: Differences in the pharyngeal site of collapse influence efficacy of non-continuous positive airway pressure therapies for obstructive sleep apnoea (OSA). Notably, complete concentric collapse at the level of the palate (CCCp) during drug-induced sleep endoscopy (DISE) is associated with reduced efficacy of hypoglossal nerve stimulation, but CCCp is currently not recognisable using polysomnography. Here we develop a means to estimate DISE-based site of collapse using overnight polysomnography. METHODS: 182 OSA patients provided DISE and polysomnography data. Six polysomnographic flow shape characteristics (mean during hypopnoeas) were identified as candidate predictors of CCCp (primary outcome variable, n=44/182), including inspiratory skewness and inspiratory scoopiness. Multivariable logistic regression combined the six characteristics to predict clear presence (n=22) versus absence (n=128) of CCCp (partial collapse and concurrent tongue base collapse excluded). Odds ratios for actual CCCp between predicted subgroups were quantified after cross-validation. Secondary analyses examined complete lateral wall, tongue base or epiglottis collapse. External validation was performed on a separate dataset (ntotal=466). RESULTS: CCCp was characterised by greater scoopiness (ß=1.5±0.6 per 2sd, multivariable estimate±se) and skewness (ß=11.4±2.4) compared with non-CCCp. The odds ratio for CCCp in predicted positive versus negative subgroups was 5.0 (95% CI 1.9-13.1). The same characteristics provided significant cross-validated prediction of lateral wall (OR 6.3, 95% CI 2.4-16.5), tongue base (OR 3.2, 95% CI 1.4-7.3) and epiglottis (OR 4.4, 95% CI 1.5-12.4) collapse. CCCp and lateral wall collapse shared similar characteristics (skewed, scoopy), diametrically opposed to tongue base and epiglottis collapse characteristics. External validation confirmed model prediction. CONCLUSIONS: The current study provides a means to recognise patients with likely CCCp or other DISE-based site of collapse categories using routine polysomnography. Since site of collapse influences therapeutic responses, polysomnographic airflow shape analysis could facilitate precision site-specific OSA interventions.

Epiglottic retroversion as a cause of upper airway obstruction: A case report.

RATIONALE: Epiglottic retroversion is the abnormal movement of the epiglottis to the rima glottis, resulting in blockage of inspiratory airflow. Acute upper airway obstruction caused by epiglottic retroversion can lead to sudden respiratory failure. Epiglottic retroversion has occasionally been reported in horses and dogs; however it is extremely rare in humans. Herein, we report a case of epiglottic retroversion causing recurrent upper airway obstruction in human. PATIENT CONCERNS: We present the case of a 74-year-old man who was diagnosed with epiglottic retroversion without evidence of epiglottis. The patient presented with recurrent episodes of abnormal breathing sounds and dyspnea. Inspiratory stridor was evident whenever the patient experienced dyspnea. DIAGNOSIS: Epiglottic retroversion was diagnosed as the cause of upper airway obstruction using fiber-optic bronchoscopy. INTERVENTIONS: The patient underwent tracheostomy to prevent acute respiratory failure because the recurrent episodes of stridor and dyspnea did not improve. OUTCOMES: The episodic dyspnea and oxygen desaturation did not relapse after tracheostomy and he could be discharged home. LESSONS: This case highlights the importance of considering epiglottic retroversion as a cause of acute upper airway obstruction.

[Repairing partial suprahyoid epiglottis-preserved circumferential defect in near total laryngectomy with anterior medial thigh flap in advanced laryngeal cancer].

Objective: To explore the feasibility to restore pronunciation function by repairing partial suprahyoid epiglottis-preserved circumferential defect in near total laryngectomy with anterior medial thigh flap in advanced laryngeal cancer. Methods: A retrospective study of 5 male patients with advanced laryngeal cancer between August 2019 and October 2022, aged 56-73 years, with an average age of 65 years were reviewed. The disease duration ranged from 3 to 24 months, with an average of 8 months. Tumor classification by location: 2 cases of glottic type, 2 cases of supraglottic type, and 1 case of subglottic type; TNM staging: 3 cases of T 4N 0M 0 stage, 1 case of T 4N 1M 0 stage, and 1 case of T 4N 2M 0 stage; American Joint Committee on Cancer (AJCC) staging (2017): stage Ⅳ. Near total laryngectomy with partial suprahyoid epiglottis-preserved and selective bilateral neck dissection were performed before the anterior medial thigh flap was used to repair the circumferential defects. The flap size ranged from 6 cm×5 cm to 8 cm×6 cm. Four patients underwent adjuvant radiotherapy and chemotherapy after operation, while 1 patient did not receive any other adjuvant treatment such as radiochemotherapy. Results: The flaps of all 5 patients survived without obvious neck infection. One patient developed a slight pharyngeal fistula after oral feeding at 1 month after operation, which healed after another week of gastric feeding. Primary healing also achieved in the thigh donor area. One patient had bilateral cervical lymph node metastasis, and 1 patient had lymph node metastasis on one side. The remaining 3 patients had no cervical nodes metastasis on both sides. All 5 patients were followed up 12-36 months, with an average of 27.6 months. Four patients had clear, audible, and hoarse voice while 1 patient (case 3) had pronunciation similar to whispering. Laryngoscopy showed that the reconstructed laryngeal inlet was fissure-shape and the reconstructed laryngo-trachea canal below the laryngeal inlet was gradually enlarged. At 1 month after operation, the gastric tube was withdrawn and the food was taken orally. There was no obvious aspiration pneumonia. The tracheostomy tube could be blocked in 4 patients for from 30 seconds to 3 minutes. Among them, 3 patients were able to make a noticeable pronunciation even when the tube was not blocked, and they were able to engage in barrier-free language communication; the tracheostomy tube could not be blocked in 1 patient who had a pronunciation similar to whispering. Preliminary voice analysis showed that the patients have a relaxed and natural pronunciation, without obvious breath-holding or air-swallowing movement, compared to patients with esophageal pronunciation. Decannulation did not achieved until the last follow-up in all 5 patients. Conclusion: The anterior medial thigh flap can repair circumferential defects after near total laryngectomy in advanced laryngeal cancer patients and achieve satisfactory pronunciation, thus can serve as an effective pronunciation rehabilitation method. The preserved part of epiglottis may play a role to prevent postoperative aspiration.

A Large Cohort Analysis of Epiglottic Phenotypes and Pharyngeal Residue.

OBJECTIVE: To describe the phenotypic characteristics of the epiglottis at rest and their impact on vallecular residue. METHODS: Videofluoroscopic studies (VFSS) were pooled from 2 Laryngology practices, and Image J was used to measure epiglottic anatomic features at rest. Studies were rated by the MBSImp and presence of vallecular residue following swallow of thin and puree boluses. A conditional inference tree analysis was performed to isolate which epiglottic parameters were risk factors for presence of vallecular reside followed by logistic regression. RESULTS: The majority of patients had a normal shaped epiglottis, followed by omega shape. The mean angle of the epiglottis from the hyoid was approximately 90°. Only abnormal epiglottic movement was associated with increased risk of residue for thin boluses (OR 35.09, CI 10.93-158.66, P < .001). However, in those with normal epiglottic movement, age >70 years old was associated with increased risk of residue (OR 3.98, CI 1.73-9.23, P = .001). For puree boluses, a normal or omega shaped epiglottis was associated with residue (OR 5.19, CI 2.41-11.51, P < .001), and this relationship was further modulated by increased distance of the epiglottic tip from the posterior pharyngeal wall. No other anatomic features of the resting epiglottis were associated with residue. Comorbidities potentially affecting swallow were infrequent in the cohort and were not associated with residue. CONCLUSION: Abnormal epiglottic movement is associated with aspiration, and in this study we find that abnormal epiglottic movement increases the risk of vallecular residue and that older age is a risk factor for residue. The resting properties of the epiglottis do not appear to be associated with abnormal epiglottic movement or residue.

Transcervical Epiglottopexy: A versatile technique for managing epiglottic prolapse.

OBJECTIVE: Epiglottic prolapse (EP) presents a unique management challenge. The objective of the present case series is to present clinical outcomes using a novel technique of transcervical epiglottopexy (TCE) in etiologically diverse cases of EP and to discuss the evolution of the surgical technique with technical modifications to optimize the surgical procedure. STUDY DESIGN: A retrospective case series review. SETTING: Tertiary care academic setting. METHODS: Pediatric cases with EP over a 3-year period. Demographic data including age, sex, presenting symptoms, operative details, and polysomnographic indices were collected. RESULTS: A total of 18 patients with a mean age of 48.88 ± 37.3 months underwent TCE. Sixty-seven percent of patients had high-grade EP (grades 3 and 4). A previous endolaryngeal epiglottopexy had been performed in 5 (28%) patients. Fourteen (78%) patients had a concurrent airway procedure performed including 4 undergoing single-stage laryngotracheal reconstruction. The mean suspension time only for the TCE part ranged from 8 to 17 minutes with a mean of 11.23 ± 3.4 minutes. A stable EP defined as a healed glossoepiglottic adhesion was achieved in all but 1 case with an overall success rate of 95%. All cases with previous failed endoscopic epiglottopexy had a stable epiglottopexy. No immediate complications were noticed. Among the late complications, the most common was the formation of granulation tissue at the site of silastic disc placement which was seen in 3 patients. CONCLUSION: TCE using an exo-endolaryngeal technique can achieve stable epiglottopexy in children with EP and can be adapted for any kind of EP.

Reliability of fluoroscopic examination of nasopharyngeal dorsoventral dimension change in pugs and French bulldogs.

OBJECTIVE: To compare intra- and interobserver agreements in two-dimensional measurements of changes in nasopharyngeal dimensions during breathing in pugs and French bulldogs. STUDY DESIGN: Experimental randomized study. ANIMALS: A total of 20 French bulldogs and 16 pugs. METHODS: Four observers with different levels of experience measured the dorsoventral dimensions of the nasopharynx during inspiration and expiration on fluoroscopy videos. Measurements were performed at the maximal narrowing of the nasopharynx for the functional method and at the level of the tip of the epiglottis for the anatomically adjusted method. The intra- and interobserver agreements of the measurements, ratio of the dynamic nasopharyngeal change (ΔL), and grade of nasopharyngeal (NP) collapse (no, partial or complete) were evaluated. RESULTS: The functional method resulted in intraobserver correlation coefficients of 0.532 (p < .01) and 0.751 (p < .01) and interobserver correlation coefficients of 0.378 (p < .01) and 0.621 (p < .01) for NP collapse grade and ΔL, respectively. The anatomically adjusted method, 0.491 (p < .01) and 0.576 (p < .01) and 0.495 (p < .01) and 0.729 (p < .01) for NP collapse grade and ΔL, respectively, were being used. One observer (radiologist) achieved intraobserver correlation coefficients >0.9 for both methods. CONCLUSION: Fair interobserver agreement was found for NP collapse grade (functional method), moderate intra- and interobserver agreements were found for NP collapse grade and ΔL (both methods) while intraobserver agreement for ΔL was good (functional method). CLINICAL SIGNIFICANCE: Both methods seem repeatable and reproducible but only for experienced radiologists. The use of ΔL may offer higher repeatability and reproducibility than grade of NP collapse regardless of the method used.

Treatment of a floppy epiglottis with upper airway stimulation therapy.

PURPOSE: To evaluate the efficacy of upper airway stimulation therapy in patients with a floppy epiglottis who have experienced continuous positive airway pressure failure or intolerance. METHODS: A retrospective single-center cohort study was conducted. Patients who received an Inspire Upper Airway Stimulation system and had a 1-year follow-up were included. Baseline and one-year in-laboratory polysomnography examinations were performed. Patient characteristics, Epworth Sleepiness Scale scores and upper airway stimulation device settings were collected. RESULTS: A total of 75 patients were included, of whom 10 had a floppy epiglottis. Patients with a floppy epiglottis had a significant therapeutic response to upper airway stimulation therapy, similar to patients without a floppy epiglottis. According to the Sher's success criteria, 90% of patients with a floppy epiglottis and 68% of patients without a floppy epiglottis were responders to therapy (p = 0.149). In the floppy epiglottis group, the apnea-hypopnea index decreased from 35.1 ± 5.5 events/hour to 11.2 ± 11.3 events/hour (95% CI (15.0, 32.9), p < 0.001), similarly in the non-floppy epiglottis group, the decline was from 36.4 ± 8.3 events/hour to 14.4 ± 9.5 events/hour (95% CI (18.6, 25.2), p < 0.001, between groups p = 0.659). Comparable reductions were observed for the other respiratory parameters. CONCLUSION: Treatment of patients with obstructive sleep apnea and a floppy epiglottis can be challenging. Continuous positive airway pressure may aggravate the epiglottis collapse. Upper airway stimulation therapy can be considered an effective alternative treatment option for patients with a floppy epiglottis who have encountered either continuous positive airway pressure failure or intolerance.

Swallowing Function After Epiglottopexy in Children.

OBJECTIVE: Epiglottopexy has been an increasingly utilized intervention in children with epiglottic prolapse and airway obstruction. Given the role of the epiglottis in protecting the airway during swallowing and the potential effect of repositioning the epiglottis on the passage of the bolus, we aimed to compare swallowing outcomes before and after epiglottopexy in children. STUDY DESIGN: A retrospective cohort study. SETTING: Tertiary care children's hospital. METHODS: Data were extracted from charts of children who underwent epiglottopexy and had a subsequent instrumental swallowing evaluation between January 2018 and September 2022. RESULTS: A total of 93 patients underwent epiglottopexy. Of these, 38 patients met inclusion requirements. The mean age at surgery was 41 ± 47 months. Most patients (n = 37, 97.4%) had significant comorbidities such as secondary airway lesions (n = 33, 91.7%), a genetic or syndromic disorder (n = 25, 69.4%), and dysphagia (n = 29, 76.3%). All patients had a concurrent procedure at the time of epiglottopexy with supraglottoplasty (n = 24, 63.2%) and lingual tonsillectomy (n = 16, 42.1%) being the most common. No changes in initiation or patterns of swallowing were noted postoperatively. A total of 7 (18.4%) patients had worsening swallow function: 2 had new-onset dysphagia, and 5 had worsening pre-existing dysphagia. Liquid or food textures penetrated remained unchanged or improved in most cases. No risk factors for worsening dysphagia were identified in our cohort. CONCLUSION: Children with medical comorbidities undergoing epiglottopexy with additional airway interventions may experience new or worsening dysphagia. However, the procedure is generally safe without notable patterned changes in the swallowing mechanism.

Three-dimensional architecture of the subepithelial corpuscular nerve ending in the rat epiglottis reconstructed by array tomography with scanning electron microscopy.

In the rat laryngeal mucosa, subepithelial corpuscular nerve endings, called laminar nerve endings, are distributed in the epiglottis and arytenoid region and are activated by the pressure changes of the laryngeal cavity. They are also suggested to play a role in efferent regulation because of secretory vesicles in the axoplasm. In the present study, the laminar nerve endings in the rat laryngeal mucosa were analyzed by 3D reconstruction from serial ultrathin sections in addition to immunohistochemistry for synapsin 1. In the light microscopy, synapsin 1-immunoreactive flattened or bulbous terminal parts of the laminar endings were also immunoreactive with VGLUT1, and were surrounded by S100- or S100B-immunoreactive Schwann cells and vimentin-immunoreactive fibroblasts. In the electron microscopy, 3D reconstruction views showed that laminar endings were composed of flattened terminal parts sized 2-5 µm in longitudinal length, overlapping in three to five multiple layers. The terminal parts of the endings were incompletely wrapped by flat cytoplasmic processes of the Schwann cells. In addition, the fibroblast network surrounded the complex of nerve endings and the Schwann cells. Several terminal parts entered through the basement membrane into the epithelial layer and attached to the basal epithelial cells, suggesting that interaction between epithelial cells and laminar nerve endings plays an important role in sensing the pressure changes in the laryngeal cavity. Secretory vesicles were unevenly distributed throughout the terminal part of the laminar nerve endings. The secretory vesicles were frequently observed in the peripheral limb of the terminal parts. It suggests that the laminar nerve endings in the larynx may release glutamate to maintain continuous discharge during the stretching of the laryngeal mucosa.

Displaced transverse laryngeal fracture from attempted hanging.

Laryngeal fractures are life-threatening injuries, frequently associated with long-term morbidity. We present a case of a man sustaining a displaced laryngeal fracture and rupture of supraglottic structures following attempted suicide by hanging from a bridge. His injuries included a tear of the thyrohyoid membrane, avulsed epiglottis and complete autopharyngotomy. All laryngeal functions were significantly impaired. Early tracheostomy, careful surgical repair, extensive multidisciplinary team (MDT) input and intensive rehabilitation all contributed towards a successful recovery. By 7 months following the initial injury, the patient had achieved excellent breathing and voicing, and a safe and competent swallow despite the extent of his initial injuries. This case demonstrates the importance of early airway management in laryngeal trauma and the role of surgical management in conjunction with swallow rehabilitation. Fundamentally, an MDT approach is essential for the holistic management of patients with laryngeal trauma.

CBCT Analysis of Oropharynx Airway Volume.

OBJECTIVE: The study was performed to analyze the oropharynx airway and examine the influence of age and gender on the oropharynx volume configuration using cone beam computed tomography. MATERIALS AND METHODS: This study examined the cone beam computed tomographic images of 51 patients 25 male and 26 females, group matched for age and gender. The oropharynx airway volume and area between the posterior nasal spine and top of the epiglottis were measured and compared. RESULTS: The statistical measurements of 51 cone beam computed tomography images showed a nonsignificant difference found between male and female regarding the age (the mean age for female 40.15 y. and for male32.72 y). Male subjects had greater oropharynx volume, a high significant difference ( P =0.005) in oropharynx volume between the 3 age groups. A significant difference was found between the smallest age group with the larger age groups. CONCLUSION: The study data revealed that the changes in measurements of oropharynx airway are age-dependent in addition to gender effect.

Tongue retraction using a McIvor blade improves airway condition during fiberoptic intubation: a randomized controlled trial.

Airway clearance is crucial for successful fiberoptic intubation. We hypothesized that tongue retraction using a McIvor blade could facilitate fiberoptic intubation. This randomized clinical trial aimed to compare intubation time and airway condition between the jaw thrust maneuver and tongue retraction with the McIvor blade during fiberoptic intubation. Ninety-four adult patients scheduled for elective surgery were randomly assigned to one of two groups. During fiberoptic intubation, airway clearance was secured by applying the jaw-thrust maneuver (J group) or by tongue retraction using the McIvor blade (M group). We assessed the total intubation time, number of attempts for tube advancement, and airway clearance at the soft palate and epiglottis levels. The total intubation time was significantly shorter in the M group than in the J group (p = 0.035). The number of attempts to advance the tube was significantly lower in the M group (p = 0.033). Airway clearance at the soft palate level was significantly better in the M group than in the J group (p = 0.027). Retracting the tongue with the McIvor blade demonstrated a better condition for fiberoptic intubation and shortened total intubation time compared with the jaw-thrust maneuver.Clinicalregistiration: CRIS; http://cris.nih.go.kr (KCT0002392) registered 28/07/2017.

Direct versus indirect epiglottis elevation in cervical spine movement during videolaryngoscopic intubation under manual in-line stabilization: a randomized controlled trial.

BACKGROUND: During videolaryngoscopic intubation, direct epiglottis elevation provides a higher percentage of glottic opening score than indirect epiglottis elevation. In this randomized controlled trial, we compared cervical spine movement during videolaryngoscopic intubation under manual in-line stabilization between the two glottis exposure methods. METHODS: Videolaryngoscopic intubation under manual in-line stabilization was performed using C-MAC® D-blade: direct (n = 51) and indirect (n = 51) epiglottis elevation groups. The percentage of glottic opening score was set equally at 50% during videolaryngoscopic intubation in both groups. The primary outcome measure was cervical spine movement during videolaryngoscopic intubation at the occiput-C1, C1-C2, and C2-C5. The secondary outcome measures included intubation performance (intubation success rate and intubation time). RESULTS: Cervical spine movement during videolaryngoscopic intubation was significantly smaller at the occiput-C1 in the direct epiglottis elevation group than in the indirect epiglottis elevation group (mean [standard deviation] 3.9 [4.0] vs. 5.8 [3.4] °, P = 0.011), whereas it was not significantly different at the C1-C2 and C2-C5 between the two groups. All intubations were successful on the first attempt, achieving a percentage of glottic opening score of 50% in both groups. Intubation time was longer in the direct epiglottis elevation group (median [interquartile range] 29.0 [24.0-35.0] vs. 22.0 [18.0-27.0] s, P < 0.001). CONCLUSIONS: When performing videolaryngoscopic intubation under manual in-line stabilization, direct epiglottis elevation can be more beneficial than indirect epiglottis elevation in reducing cervical spine movement during videolaryngoscopic intubation at the occiput-C1. TRIAL REGISTRATION: Clinical Research Information Service (number: KCT0006239, date: 10/06/2021).

The relationship between bi-spectral index and VOTE score in evaluation of drug-induced sleep endoscopy: A systematic meta-analysis.

OBJECTIVE: The aim of this study was to investigate both the presence and severity of collapse in anatomical regions defined by the VOTE score (velum, orofarinx, tongue, and epiglottis), during drug induced sleep endoscopy (DISE) in patients diagnosed with obstructive sleep apnea, based on the bi-spectral index (BIS) sedation level. METHODS: In order to conduct a meta-analysis of articles examining the relationship between the VOTE score and BIS sedation level in determining the presence and severity of upper airway collapse during DISE, a literature review was performed. RESULTS: As a result of the search made in the specified databases, a total of 1864 articles were reached. Five articles included in this review that had sufficient statistical data to be included in the meta-analysis were found. A statistically significant correlation was found between the BIS sedation level and the areas of obstruction in the VOTE score. The strongest association is at the epiglottis level, followed by the velum, oropharynx, and tongue, respectively (CC: 0.639, CC: 0.53, CC: 0.49, and CC: 0.346, P < .001). In the subgroup analysis of publications with BIS sedation levels in the range of 60 to 65, the distribution in the epiglottis region was heterogeneous, and it was found to be statistically significant according to the random effect model (P < .001). The distribution in the tongue was homogeneous, and it was found to be statistically significant according to the fixed effect model (P < .001). When the publications in which the BIS sedation level is in the range of 65 to 75 are examined according to the areas of obstruction; the distribution in 4 anatomical regions was homogeneous and statistically significant according to the fixed effect model (P < .001). CONCLUSION: It was found that BIS sedation levels during DISE application in obstructive sleep apnea patients were associated with obstruction of the anatomical regions of the upper airway. The strongest association was found at the epiglottis level, followed by the velum, oropharynx, and tongue, respectively. It is helpful to monitor the sedation level with BIS in order to better define the collapsed areas during DISE application. However, more studies are needed to better understand the relationship between BIS sedation values and sleep stages.