Comparison of drug-induced sleep endoscopy and Müller's maneuver in diagnosing obstructive sleep apnea using the VOTE classification system

Polysomnographic Findings Versus Degree of Obstruction During Drug-Induced Sleep Endoscopy and Muller's Maneuver

PURPOSE

To investigate associations between polysomnographic findings and the severity of upper airway obstructions during Muller's Maneuver (MM) and Drug-Induced Sleep Endoscopy (DISE) in patients with obstructive sleep apnea syndrome (OSAS).

METHODS

This was a prospective cohort study. Adult patients newly diagnosed with OSAS in a tertiary sleep center were included consecutively and evaluated by polysomnography and MM. They then underwent DISE in an operating room. The associations between polysomnographic findings and the severity of upper airway obstructions during MM and DISE were assessed. Also, the degree and pattern of obstructions were compared using a modified VOTE questionnaire.

RESULTS

145 patients (mean age 41.5 ± 10.1 years) were enrolled. There were no associations between Respiratory Disturbance Index (RDI), mean and lowest O2 saturation, and body mass index on the one hand, and obstruction degree in MM and DISE (p > 0.05). However, a significant positive correlation was observed between RDI and total VOTE scores in DISE and MM (r = 0.179, p = 0.031 and r = 0.221, p = 0.008 respectively). There were no differences between MM and DISE in diagnosing the degree of obstruction in the velum area (p = 0.687) and the epiglottis (p = 0.50). However, a significant difference was observed between the two techniques in the oropharynx lateral wall (p < 0.001) and tongue base (p = 0.017).

CONCLUSION

Although there was no association between polysomnographic findings and the severity of obstruction in MM and DISE for the separate levels of the upper airway, obstruction severity may be assessed more accurately by total VOTE score, which is representative of RDI severity.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Comparing Diagnostic Efficacy of Imaging During Muller's Maneuver Versus Drug Induced Sleep Endoscopy in Obstructive Sleep Apnoea

The aim of the study was to compare the diagnostic efficacy of quantitative computed tomography (CT) based upper airway analysis using the Muller's maneuver (MM) and compare the findings with drug induced sleep endoscopy (DISE). A prospective observational study was conducted on 50 adult patients with symptoms of OSA and having apnoea-hypopnea index more than 5. They further underwent CT during normal breathing and during MM; findings of which were compared with DISE. Collapse at velum had statistically significant correlation with collapse at retropalatal level in CT (in MM) (P value = 0.001; r = 0.536). Base of tongue in DISE correlates significantly with retroglossal collapse on CT (P value = 0.002; r = 0.423). Epiglottic and oropharyngeal collapse had no correlation with any CT parameter. Collapse in CT as measured during MM shows significant correlation with DISE findings at velum and tongue base but cannot solely predict all levels without the aid of DISE.

Relationship of Upper Airway Collapse with Severity of Sleep Apnoea and Sleepiness

Introduction: Obstructive sleep apnoea (OSA) is characterized by repeated episodes of upper airway collapse. A review of literature shows limited and conflicting data regarding impact of upper pharyngeal collapse on severity of OSA and degree of sleepiness. Objective: To evaluate the association of the number of levels and degree of upper airway collapse and severity of OSA. Methods: This is a retrospective study including all patients with OSA over a two-year period. Data regarding neck circumference (NC), body mass index (BMI), nasopharyngolaryngoscopy with Muller's manoeuvre, Epworth sleepiness scale (ESS) questionnaire and a full night polysomnography were collected. Correlation of the number of sites involved and degree of collapse at each site (velum, lateral pharyngeal wall- Level I, base of tongue - Level II and epiglottis - Level III) with BMI, NC, AHI and ESS were assessed. Results: Of the 144 patients, 98% had collapse at Level I. 80% of patients had multisegmental collapse with 30% having collapse at all three levels. The number of levels and the severity of collapse did not have a proportionate effect on the AHI and ESS and were not directly dependent on the BMI. However, changes in NC had a significant effect on the severity of collapse.Conclusion: Severity of OSA and degree of sleepiness were not directly dependent on the severity and the number of levels of collapse. Since majority of the patients had multi segmental collapse, the study highlights the importance of careful assessment of all levels to tailor management strategies for optimum patient management.

Suspension-expansion pharyngoplasty: a modified technique for oropharyngeal collapse in obstructive sleep apnea

BACKGROUND AND PURPOSE

Lateral pharyngeal wall (LPW) collapse plays a fundamental role in the pathogenesis of obstructive sleep apnea (OSA) and might determine the severity of the disease. This study presents the suspension/expansion pharyngoplasty (SEP) for the treatment of selected cases of OSA. The procedure aimed to splint LPW collapse via supporting and lateralization of both superior constrictor muscle (SCM) and palatopharyngeal muscle (PPM) individually and in two different planes.

METHODS

Twenty-one adult patients with single-level OSA who showed a lateral pattern of collapse at the oropharyngeal region had the modified procedure (SEP). The basic steps are the individual dissection of the muscular components of the lateral pharyngeal wall: SCM which was sutured anteriorly to the anterior tonsillar pillar and the PPM which was suspended to the pterygomandibular raphe. The supra-tonsillar fat was preserved.

RESULTS

At 9-12 months, highly significant improvement was reported as regards the mean Apnea hypopnea index and the mean lowest oxygen saturation (p < 0.000). The Epworth Sleepiness Scale and VAS-snoring showed a significant (p < 0.05) reduction. The oxygen desaturation index showed significant improvement. Non-significant improvements were reported as regards the percentage of total sleep time with oxygen saturation below 90%. According to Sher criteria, successful outcomes were reported in 17 patients.

CONCLUSION

SEP could widen the pharyngeal airway and could support the collapsible lateral pharyngeal wall guarding against soft tissue collapse. In selected subjects, SEP had reported subjective and objective favorable outcomes with no significant comorbidities. The procedure could be combined with other procedures in multilevel surgery.

LEVEL OF EVIDENCE: 4

Role of functional and anatomic study in sleep endoscopy for treatment of OSA

Objective

To describe a clear and intuitive way to analyse the anatomical meaning of images observed in Drug-induced Sleep Endoscopy (DISE) to fully understand the obstructive dynamics and therefore opt for a tailor-made pharyngeal surgical technique.

Methods

From January 2016 to December 2020, 298 patients who underwent DISE were selected according to inclusion criteria.

Results

The case series consisted of 204 males and 94 females with a mean age of 56 years. Body mass index ranged from 19 kg/m² to 34 kg/m² with a median of 26.5 kg/m². Median Apnoea-Hypopnea Index (AHI) was 27 (range 5-62.3). The authors also observed four palate pharyngeal phenotypic patterns of collapse and clarify the morphology and role of the main muscles involved in upper airway collapse.

Conclusions

DISE is fundamental to determine the collapse site in patients affected by obstructive sleep apnoea syndrome. The velopharyngeal region is the most common site of obstruction and lateral pharyngeal wall collapse is the major determining factor. DISE can lead to a deeper understanding of the obstructive dynamic patterns and a more precise identification of the muscle bundles responsible for upper airway collapse.

Guidelines of the French Society of ENT (SFORL): Drug-induced sleep endoscopy in adult obstructive sleep apnea syndrome

OBJECTIVES

To determine the indications, anesthesiological and surgical procedure and interest of drug-induced sleep endoscopy in the treatment of adult obstructive sleep apnea syndrome.

DESIGN

A redactional committee of 17 experts was set up. Conflicts of interest were disclosed and followed up throughout the process of drawing up the guidelines. The work received no funding from any firm dealing in health products (drugs or devices). The GRADE (Grading of Recommendations Assessment, Development and Evaluation) method was applied to assess the quality of the data on which the guidelines were founded. It was stressed that strong recommendations should not be made on the basis of poor-quality or insufficient data.

METHODS

The committee studied 29 questions on 5 topics: indications and contraindications, anesthetic technique, surgical technique, interpretation and reporting of results, and management guided by results.

RESULTS

Expert review and application of the GRADE method led to 30 guidelines: 10 with high level of evidence (Grade 1+ or 1-), 19 with low level (GRADE 2+ or 2-) and 1 expert opinion.

CONCLUSION

Experts fully agreed on the strong guidelines formalizing the indications and modalities of drug-induced sleep endoscopy for adult obstructive sleep apnea syndrome.

Optimizing Mandibular Advancement Maneuvers during Sleep Endoscopy with a Titratable Positioner: DISE-SAM Protocol

Mandibular advancement devices (MAD) are an effective alternative treatment to CPAP. Different maneuvers were performed during drug sleep-induced endoscopy (DISE) to mimic the effect of MAD. Using the Selector Avance Mandibular (SAM) device, we aimed to identify MAD candidates during DISE using a titratable, reproducible, and measurable maneuver. This DISE-SAM protocol may help to find the relationship between the severity of the respiratory disorder and the degree of response and determine the advancement required to improve the collapsibility of the upper airway. Explorations were performed in 161 patients (132 males; 29 females) with a mean age of 46.81 (SD = 11.42) years, BMI of 27.90 (SD = 4.19) kg/m², and a mean AHI of 26.51 (SD = 21.23). The results showed no relationship between severity and MAD recommendation. Furthermore, there was a weak positive relationship between the advancement required to obtain a response and the disease severity. Using the DISE-SAM protocol, the response and the range of mandibular protrusion were assessed, avoiding the interexaminer bias of the jaw thrust maneuver. We suggest prescribing MAD as a single, alternative, or multiple treatment approaches following the SAM recommendations in a personalized design.

Diagnosis of upper airways collapse in moderate-to-severe OSAHS patients: a comparison between drug-induced sleep endoscopy and the awake examination

PURPOSE

Compare awake evaluation (modified Mallampati score-MMs, Müller maneuver-MM) to drug-induced sleep endoscopy (DISE) findings according to NOHL (nose-oropharynx-hypopharynx-larynx) classification in moderate-to-severe OSAHS patients.

METHODS

43 moderate-to-severe OSAHS patients referred to our ENT department were enrolled over a 2-year period. In this observational prospective study, each patient was evaluated by the same ENT team both in wakefulness and during pharmacologically induced sleep. Level and severity of the obstruction were described.

RESULTS

The comparison of degree of collapsibility was statistically significative only at hypopharyngeal level: 41.8% of the patients showed a hypopharyngeal obstruction in wakefulness whereas 88.3% in DISE (p = 0.000). Laryngeal level was found in 18.6% patients during awake examination, conversely DISE demonstrated laryngeal obstruction in 4.6%. DISE identified significantly higher incidence of multilevel collapses (p = 0.001). However, the incidence of oropharyngeal obstruction in patients classified as MMs I and II was significantly higher in DISE compared to MM (p = 0.021).

CONCLUSION

DISE is the best predictor of hypopharyngeal obstruction, whereas MM underestimates the severity of the collapse at this level. DISE is more reliable than MM to identify the obstruction in patients with MMs score I and II.

Effectiveness of drug-induced sleep endoscopy in improving outcomes of barbed pharyngoplasty for obstructive sleep apnea surgery: a prospective randomized trial

PURPOSE

To observe the effectiveness of preoperative drug-induced sleep endoscopy in improving surgical results of patients undergoing single-level barbed pharyngoplasty surgery for OSA, using a prospective randomized model.

METHODS

A single-center randomized controlled trial with two prospective arms was carried out to compare functional results in patients treated with barbed reposition pharyngoplasty (BRP) surgery without a preoperative drug-induced sleep endoscopy (DISE) evaluation vs patients treated with BRP surgery performed after DISE evaluation of sites/patterns of collapse.

RESULTS

We compared 50 patients who underwent BRP without a preoperative DISE evaluation (Group A) and 42 patients (Group B) treated with BRP surgery but preoperatively selected by means of a preoperative DISE. In this second group of patients, after DISE evaluation, 70% of patients were selected for single-level BRP surgery because they showed an isolated velopharyngeal collapse at the DISE evaluation, without obstruction at other upper airway levels evaluated. Both groups of patients showed a statistically significant difference between preoperative and postoperative values of AHI, ODI, and LOS (p<0.05 in all cases). Comparing Group A and Group B patients, the therapeutic success rate was found to be 60% in patients treated without preoperative DISE evaluation and 83% in patients treated with preoperative DISE (p = 0.02).

CONCLUSION

DISE appears to improve the surgical results of single-level velopharyngeal surgery due to the possibility of excluding patients with obstruction of the base of the tongue, the hypopharynx, and the epiglottis/larynx.

Upper airway collapse characteristics in adult patients with OSA and previous tonsillectomy

PURPOSE

To analyze upper airway (UA) collapse patterns through drug-induced sleep endoscopy (DISE) in adult patients with obstructive sleep apnea (OSA) who previously underwent tonsillectomy.

METHODS

This was a retrospective study on patients with OSA who underwent DISE between June 1, 2013 and July 30, 2017 at Stanford Hospital. Subjects who had prior tonsillectomy history were classified into the tonsil0 group, whereas others were classified into the tonsil1 and tonsil2/3/4 group based on tonsil grade. UA collapse characteristics were recorded and analyzed among groups according to Velum, Oropharynx, Tongue base and Epiglottis (VOTE) classification.

RESULTS

A total of 205 individuals were included, 38 in tonsil0 group, 104 in tonsil1 and 63 in tonsil2/3/4. The tonsil0 group had a higher percentage of anterior-posterior (AP) velum (58%) and tongue base (45%) collapse compared with the tonsil2/3/4 group (22%, P = 0.0003 and 22%, P = 0.02, respectively) but less oropharyngeal lateral wall collapses (29% vs 53%, P = 0.02). Most of the tonsil0 group (70%) showed multi-sites collapse pattern, the percentage of combined obstruction in both palatopharyngeal and hypopharyngeal region was higher (50% vs 29%, P = 0.03). The difference of velum complete AP collapse remained significant after adjusting for age and BMI (Odds Ratio = 0.33, 95% CI 0.12-0.86, P = 0.02). No significant differences were found between the tonsil0 and tonsil1 groups.

CONCLUSION

Compared with individuals with larger tonsils (grade 2 to 4), those with previous tonsillectomy and OSA were susceptible to the velum AP configuration collapse. Diversity of multi-sites obstruction and combined collapse in both palatopharyngeal and hypopharyngeal level was the main characteristic.

The clinical characteristics of patients with an isolate epiglottic collapse

OBJECTIVE

We analyzed the clinical characteristics of patients with isolated epiglottic collapse (IEC) who had an epiglottic anteroposterior (AP) collapse as the only cause of snoring during drug-induced sleep endoscopy (DISE).

METHODS

A retrospective analysis of 334 consecutive DISE examinations was performed. Patients who had only epiglottic AP collapse were designated as the IEC group. There were four age- and sex-matched controls for each case, and these patients were designated as the control group. Demographic factors, polysomnography findings, cephalometry, and awake nasopharyngoscopic findings were analyzed.

RESULTS

A total of 11 IEC cases and 44 controls were included. The IEC group had a significantly lower apnea-hypopnea index, higher minimum oxygen saturation level, lower body mass index, and shorter mandible plane to hyoid distance than the controls. However, there were no differences in epiglottic shape or curvature between the two groups. In addition, no IEC was noted during awake endoscopy. Nine (81.8%) epiglottic collapses were resolved with the mouth open and jaw thrust maneuver, which simulated the use of an oral appliance. Six (54.4%) were resolved with head turning, mimicking the lateral sleep position.

CONCLUSION

The clinical characteristics of IEC patients differed from the control group, and IEC could not be identified during awake endoscopy. Therefore, patients with severe snoring but AHI < 5 or mild sleep apnea on polysomnographic findings and DISE, should be considered likely to have IEC. In addition, use of an oral appliance is recommended as an effective treatment for IEC.

Dexmedetomidine versus propofol at different sedation depths during drug-induced sleep endoscopy: A randomized trial

OBJECTIVES/HYPOTHESIS

The aim of this study was to compare the effect of dexmedetomidine and propofol on airway dynamics, cardiorespiratory system, and emergence following drug-induced sleep endoscopy (DISE).

STUDY DESIGN

Prospective, randomized, single-blinded study.

METHODS

Sixty patients age 18 to 65 years in American Society of Anesthesiologists physical status groups 1 and 2 scheduled to undergo DISE were randomly allocated to either Group P (N = 30; receiving propofol infusion at 50-150 μg/kg/min) or Group D (N = 30; receiving dexmedetomidine bolus of 1 μg/kg followed by infusion at 0.5-1.0 μg/kg/hr). DISE was done at light sleep and deep sleep. Airway obstruction at tongue base was recorded as primary outcome. Airway obstruction at velum, oropharyngeal lateral wall, and epiglottis level during light and deep sedation, hemodynamic and respiratory parameters, time to attain sufficient sedation, time for emergence from sedation, and any adverse events during DISE with the two study drugs were recorded as secondary outcomes.

RESULTS

There was a greater degree of obstruction at the tongue base level (P = 0.001) and Oropharynx level (P = 0.017) in Group P compared with Group D during deep sedation. Increase in airway obstruction from light to deep sleep was seen with propofol at the oropharynx (P = 0.0185) and tongue base (P = 0.0108) levels. Two patients (6.6%) in Group D and 10 patients (33.3%) in Group P showed oxygen saturation below the minimum oxygen saturation recorded during polysomnography. Time to open eyes to call after stopping sedation was significantly less in Group P (P = 0.005).

CONCLUSIONS

Dexmedetomidine shows a lesser degree of airway collapse and higher oxygen saturation levels at greater sedation depth during DISE. Propofol has a faster onset and emergence from sedation.

LEVEL OF EVIDENCE

1b Laryngoscope, 130:257-262, 2020.

The role of drug-induced sleep endoscopy: predicting and guiding upper airway surgery for adult OSA patients

PURPOSE

Obstructive sleep apnea (OSA) is a common sleep disorder that can be corrected with upper airway surgery. Prior to surgery, drug-induced sleep endoscopy (DISE) is routinely used to evaluate obstruction sites and severity. Evidence suggests that the findings of DISE may relate to the final surgical outcome. Therefore, we evaluated the ability of drug-induced sleep endoscopy to predict the final effect of upper airway surgery and potentially to guide surgical treatment decision-making.

METHODS

A retrospective analysis was conducted on 85 adult patients with OSA (50 men with mean apnea-hypopnea index [AHI] 30 ± 15 events/h) who underwent DISE followed by tonsillectomy, uvulopalatopharyngoplasty (UPPP), or a combination of the two. Surgery outcome was evaluated at follow-up by polysomnography. Success response to surgery was defined as a postoperative value of the AHI< 20 events/h and more than 50% postoperative reduction of AHI.

RESULTS

Of the 85 patients evaluated, 48 (53%) were responders. DISE revealed significant differences between the two groups. Specifically, complete circumferential collapse at the velum and complete anterior-posterior collapse at the tongue base occurred at higher frequencies in nonresponders. In contrast, the presence of grade 3-4 tonsillar hypertrophy and anterior-posterior mild/partial collapse at the velum were positively associated with responders.

CONCLUSIONS

Our results suggest that DISE may help predict the final outcome of tonsillectomy, UPPP, or a combination of the two in adult patients with OSA. The use of DISE shows potential to guide treatment decisions for individual patients with OSA.

Upper Airway Areas, Volumes, and Linear Measurements Determined on Computed Tomography During Different Phases of Respiration Predict the Presence of Severe Obstructive Sleep Apnea

PURPOSE

The objective of this study was to analyze the potential of using low-dose volumetric computed tomography (CT) during different phases of respiration for identifying patients likely to have severe obstructive sleep apnea (OSA), defined as a respiratory disturbance index (RDI) higher than 30.

PATIENTS AND METHODS

A prospective study was undertaken at the Ramathibodi Hospital (Bangkok, Thailand). Patients with diagnosed OSA (N = 82) were recruited and separated into group 1 (RDI, ≤30; n = 36) and group 2 (RDI, >30; n = 46). The 2 groups were scanned by low-dose volumetric CT while they were 1) breathing quietly, 2) at the end of inspiration, and 3) at the end of expiration. Values for CT variables were obtained from linear measurements on lateral scout images during quiet breathing and from the upper airway area and volume measurements were obtained on axial cross-sections during different phases of respiration. All CT variables were compared between study groups. A logistic regression model was constructed to calculate a patient's likelihood of having an RDI higher than 30 and the predictive value of each variable and of the final model.

RESULTS

The minimum cross-sectional area (MCA) measured at the end of inspiration (cutoff point, ≤0.33 cm²) was the most predictive variable for the identification of patients likely to have an RDI higher than 30 (adjusted odds ratio [OR] = 5.50; 95% confidence interval [CI], 1.76-17.20; sensitivity, 74%; specificity, 72%,), followed by the MCA measured at the end of expiration (cutoff point, ≤0.21 cm²; adjusted OR = 3.28; 95% CI, 1.05-10.24; sensitivity, 70%; specificity, 68%).

CONCLUSION

CT scanning at the ends of inspiration and expiration helped identify patients with an RDI higher than 30 based on measurement of the MCA. Low-dose volumetric CT can be a useful tool to help the clinician rapidly identify patients with severe OSA and decide on the urgency to obtain a full-night polysomnographic study and to start treatment.

Insights since FDA Approval of Hypoglossal Nerve Stimulation for the Treatment of Obstructive Sleep Apnea

Purpose

The literature on hypoglossal nerve stimulation (HNS) for the treatment of moderate-to-severe obstructive sleep apnea (OSA) was reviewed from 2014, the time of FDA approval for the Inspire Systems device, to 2017 for themes that might be useful conceptually and practically in the consideration of this new non-anatomic surgical therapy.

Recent Findings

there are now further follow-up articles since the 12-month results for Apnea Reduction (STAR) trial of the Inspire device, and post-approval publications which report similar and/0r improved AHI outcomes. Other emerging themes include drug-induced sedation endoscopy (DISE) as a tool in assessment of eligibility and a more detailed understanding of mechanisms for an HNS effects.

Summary

The post-STAR literature provides guidelines for an integrated coordination of medicine and surgery to appropriately screen and manage patients.

Dexmedetomidine versus propofol during drug-induced sleep endoscopy and sedation: a systematic review

BACKGROUND

The purpose of the present study is to review the international literature, using a systematic review, for studies comparing propofol and dexmedetomidine for drug-induced sleep endoscopy (DISE) or sedation in which there is a description of the effect of the agents on the upper airway and associated variables (e.g., vital signs, sedation scores).

METHODS

This is a systematic review through October 4, 2016. PubMed/MEDLINE and four additional databases were accessed for this study.

RESULTS

Two hundred twenty studies were screened, 79 were downloaded, and 10 met criteria. The majority of the studies identified dexmedetomidine as the preferred pharmacologic agent for DISE due to an overall safer and more stable profile based upon hemodynamic stability. However, propofol provided greater airway obstruction with oxygen desaturations. With either agent, the degree of obstruction in the upper airway lacks some degree of validity as to whether the obstructions accurately represent natural sleep or are simply a drug-induced effect.

CONCLUSION

Dexmedetomidine and propofol have their advantages and disadvantages during DISE. Generally, dexmedetomidine was preferred and seemed to provide a more stable profile based upon cardiopulmonary status. However, propofol has a quicker onset, has a shorter half-life, and can demonstrate larger degrees of obstruction, which might more accurately reflect what happens during REM sleep. Additional research is recommended.

[Drug-induced sedation endoscopy-quo vadis? : Review and outlook]

BACKGROUND

Drug-induced sedation endoscopy (DISE) is a diagnostic procedure which allows evaluation of the collapsibility of the upper airway. According to expert opinion, it is possible to imitate nocturnal collapsibility and perform a realistic investigation of the site of obstruction and vibration. This should enable sufficient and precise therapeutic advice to be given solely on the basis of clinical assessment.

OBJECTIVE

The current publication critically evaluates the present state of development of DISE and its potential indications.

MATERIALS AND METHODS

A PubMed literature research was performed using "sleep" and "endoscopy" or "DISE" as keywords. Relevant publications were evaluated.

RESULTS

The present publication provides a historical summary of the available publications and relates these to other methods for examining obstructive sleep apnea. The present state of DISE in terms of drugs applied, grading systems, and validity is evaluated. Indications for DISE are described and critically discussed on the basis of literature data.

CONCLUSION

DISE provides deep insights into the genesis of obstructions of the upper airway and snoring. Although its value for diagnosis and treatment of sleep-disordered breathing could not yet be demonstrated for all non-CPAP (continuous positive airway pressure) therapies, DISE could identify predictive parameters some methods. Further potential indications for DISE might be predictive examinations for mandibular advancement devices and respiration-synchronous neurostimulation of the hypoglossal nerve. DISE will thus remain a valuable diagnostic tool for obstructive sleep apnea and rhonchopathy.