Tongue mechanical characteristics and genioglossus muscle EMG in obstructive sleep apnoea patients

Tongue mechanical characteristics and genioglossus muscle EMG in obstructive sleep apnoea patients. Respir Physiol Neurobiol. 2004 May 20;140(2):155-64. Blumen MB, de La Sota AP, Quera-Salva MA, Frachet B, Chabolle F, Lofaso F. Head and Neck Surgery Department, Foch Teaching Hospital, Suresnes, France.

Introduction : The increased genioglossus muscle (GGm) activity seen in obstructive sleep apnoea syndrome (OSAS) may lead to increased fatigability or longer recovery time of the tongue. Material and method :Maximal force, endurance, and recovery times of the tongue, electromyogram (EMG) absolute value, and EMG spectral analysis of the GGm obtained during submaximal contractions were compared in eight individuals without chronic snoring and eight OSAS patients. Results : Endurance time values were not significantly different between the two groups (P = 0.40). Time to recovery of initial maximal force was significantly greater in the OSAS group (P = 0.01). Final EMG median frequency was significantly higher (P = 0.01) and the final low-frequency EMG component smaller in the OSAS patients (P = 0.02). Patients did not have changes in endurance time or fatigability but had longer recovery times and changes in spectral analysis variations. Conclusion : This functional investigation may be helpful in determining the presence of OSAS and the potential contribution of the tongue to pharyngeal obstruction. Copryright 2004 Elsevier B.V

Genioglossal electromyogram during maintained contraction in normal humans. Eur J Appl Physiol. 2002 Nov;88(1-2):170-7. Epub 2002 Sep 17. Blumen MB, Perez de La Sota A, Quera-Salva MA, Frachet B, Chabolle F, Lofaso F. Head and Neck Surgery Department, Foch Teaching Hospital, Suresnes, France

Introduction : Knowledge of the fatigability of the genioglossus muscle is of interest because this muscle prevents pharyngeal collapse, especially during sleep. Material and methods : In the present investigation, signs of fatigue in the genioglossus muscle were studied by measuring the tongue endurance using a force transducer and electromyographic (EMG) activity of the genioglossus muscle in eight nonapnoeic men. Mean absolute EMG values and spectrum analysis were calculated at three levels of submaximal effort. Results : Median frequency and the force:mean absolute EMG value ratio were independent of force level (F = 0.37, P = 0.93; F = 0.35, P = 0.94, respectively) but dependent on effort duration (F = 52, P < 0.0001; F = 16, P < 0.0001). Force:mean absolute EMG value and logarithmic median frequency decreased linearly with respect to time and were similar at the three force levels when time was expressed as a percentage of total test time (F = 0.37, P =

0.93). The decrease in median frequency was ascribable to a larger increase in low- than in high-frequency components, as shown by the significant decrease in the high-frequency:lowfrequency ratio (F = 27, P < 0.0001) with time. Conclusion : The method of investigation used in this study allowed detection of the behaviour of the tongue during fatigue and, therefore, should be useful in disorders where mechanical failure of the tongue is suspected, such as the sleep apnoea syndrome or in neuromuscular disorders.

Radiofrequency ablation for the treatment of mild to moderate obstructive sleep apnea. Laryngoscope. 2002 Nov;112(11):2086-92. Blumen MB, Dahan S, Fleury B, Hausser-Hauw C, Chabolle F. Department of Otolaryngology-Head and Neck Surgery, Foch Hospital, Suresnes, France.

OBJECTIVES/HYPOTHESIS: Obstructive sleep apnea syndrome is due to pharyngeal obstructions, which can take place at the level of the soft palate. Temperature-controlled radiofrequency ablation has been introduced as being capable of reducing soft tissue volume and excessive compliance. The aim of the study was to evaluate prospectively the possible efficacy of temperature-controlled radiofrequency ablation applied to the soft palate in subjects with mild to moderate obstructive sleep apnea syndrome. STUDY DESIGN: Twenty-nine patients with a respiratory disturbance index between 10 and 30 events per hour, body mass index equal to or less than 30 kg/m2, and obstruction at the level of the soft palate were included in a pilot, prospective nonrandomized study. METHODS: Snoring and daytime sleepiness were evaluated subjectively. Treatment (maximum of three sessions) was discontinued when the bed partner was satisfied with the snoring level. A full night recording was performed at least 4 months after the last treatment. RESULTS: Mean snoring level decreased significantly from 8.6 +/- 1.3 to 3.3 +/- 2.5 on a visual analogue scale (0-10). Daytime sleepiness decreased nonsignificantly. Mean respiratory disturbance index decreased significantly from 19.0 +/- 6.1 events per hour to 9.8 +/- 8.6 events per hour. Mean lowest oxygen saturation value increased nonsignificantly from 85.3% +/- 4.1% to 86.4% +/- 4.4%. Of the patients, 65.5% were cured of their disease. CONCLUSIONS: Temperature-controlled radiofrequency ablation was effective in selected patients with mild to moderate obstructive sleep apnea syndrome. A full-night polysomnography is required after completion of treatment to rule out residual disease

Radiofrequency versus LAUP for the treatment of snoring. Otolaryngol Head Neck Surg. 2002 Jan;126(1):67-73. Blumen MB, Dahan S, Wagner I, De Dieuleveult T, Chabolle F. Department of Otolaryngology, Head and Neck Surgery, Foch Hospital, Suresnes, France.

OBJECTIVE: To compare efficacy and tolerance of controlled temperature radiofrequency and laser-assisted uvulopalatopharyngoplasty (LAUP) for the treatment of snoring.

METHODS: This was a prospective, nonrandomized study on 30 patients who snored. All patients had a sleep night study. Only patients with simple snoring or mild sleep apnea and soft palate obstruction were included. Efficacy was subjectively evaluated by the bed partner 2 months after the last treatment. Tolerance was estimated daily by the patient during 18 first postoperative days. Discomfort, pain, medication intake, diet, and number of days off from work were assessed. RESULTS: Both treatments were effective on snoring. Mean discomfort and pain as well as mean intake of analgesics were significantly greater with laser-assisted uvulopalatopharyngoplasty. CONCLUSION: Controlled temperature radiofrequency was as effective as laser-assisted uvulopalatopharyngoplasty on snoring on a short-term basis but was better tolerated.

Radiofrequency is a safe and effective treatment of turbinate hypertrophy. Laryngoscope. 2001 May;111(5):894-9. Coste A, Yona L, Blumen M, Louis B, Zerah F, Rugina M, Peynegre R, Harf A, Escudier E. Service Oto-Rhino-Laryngologie et Chirurgie Cervico-Faciale, Hopital Henri Mondor (Assistance Publique des Hopitaux de Paris) Faculte de Medecine de Creteil, 51 Avenue du Marechal de Lattre de Tassigny, 94010 Creteil cedex, France.

OBJECTIVE: To evaluate the safety and efficacy of radiofrequency for reduction of inferior turbinate volume. STUDY DESIGN: Prospective before-and-after trial. METHODS: Fourteen patients complaining of chronic nasal obstruction and failing to respond to medical treatment were prospectively enrolled. All patients presented with inferior turbinate hypertrophy and no septal deformity. Radiofrequency inferior turbinate tissue reduction with three punctures in each turbinate (mean energy/puncture: 342 +/- 36 J, mean duration: 69 +/- 17 s, plateau tissue temperature: 75 +/- 6.4 degrees C). Patients were evaluated before and on days 3, 7, and 60 after intervention. RESULTS: No postoperative pain or complications were reported. Evaluation of nasal obstruction, quantified by visual analogue scale, showed a significant decrease of day time and nighttime obstruction after surgery. Acoustic rhinometry measurements showed that turbinate hypertrophy was significantly reduced in the sitting and supine positions on day 60 after surgery. Saccharin transit times decreased significantly on day 60 compared with preoperative measurements. Ciliary beat frequency, measured in vitro in nasal epithelial cells sampled from the inferior turbinate by brushing, was not significantly different before surgery and on day 60 after surgery. In the same samples, ciliated cells were the most abundant epithelial cell type before and after surgery, although in five cases, moderate numbers of squamous cells were detected on either day 7 or day 60 after surgery. CONCLUSION: Radiofrequency is a safe surgical procedure capable of reducing turbinate volume without altering the nasal mucosa, and causing minimal discomfort for the patient.

[Treatment of snoring with controlled temperature radiofrequency: short- and mid-term tolerance and efficacy] Ann Otolaryngol Chir Cervicofac. 2000 Dec;117(6):349-358. Blumen MB, Dahan S, de Dieuleveult T, Wagner I, Chabolle F. Service ORL et chirurgie cervico-faciale, Hopital Foch 40, rue Worth 92160 Suresnes, France.

INTRODUCTION : Uvulopalatopharyngoplasty and laser pharyngotomy can provide effective and definitive cure of snoring. These methods are however very painful. The ideal treatment would be not only effective but also pain free. MATERIAL AND METHODS: We assessed prospectively the efficacy and tolerance to temperature controlled radiofrequency (somnoplasty). This technique was applied to the velar palate in 15 snoring patients. Self assessment was used to evaluate outcome. The patients daily recorded: uneasiness, pain, drug use, and food intake. Their spouse scored snoring for 6 to 8 weeks after the end of treatment and more than 6 months after the last treatment session. RESULTS: We achieved 80% success after 2.1 sessions. Pain was minimal. A sensation of uneasiness was frequent and led to minimal drug use. After a mean 13 months, half of the patients experienced a recurrence or an aggravation of their snoring level. Overall satisfaction rate was 69%. CONCLUSION: These preliminary results suggest that radiofrequency is well tolerated and effective in the short- and mid-term for the treatment of snoring.

A comparative model: reaction time performance in sleep-disordered breathing versus alcohol-impaired controls. Laryngoscope. 1999 Oct;109(10):1648-54. Powell NB, Riley RW, Schechtman KB, Blumen MB, Dinges DF, Guilleminault C. Stanford Sleep Disorders and Research Center, Department of Psychiatry and Behavioral Science, Stanford University Medical School, California, USA.

OBJECTIVES/HYPOTHESIS: Patients with sleep-disordered breathing have reaction time deficits that may lead to catastrophic accidents and loss of life. Although safety guidelines do not exist for unsafe levels of sleepiness, they have been established for unsafe levels of alcohol consumption. Since reaction time performance is altered in both, we prospectively used seven measures of reaction time performance as a comparative model in alcoholchallenged normal subjects with corresponding measures in subjects with sleep-disordered breathing. STUDY DESIGN: Institutional Review Board-approved, nonrandomized prospective controlled study. METHODS: Eighty healthy volunteers (29.1+/-7.5 y of age, 56.3% female subjects) performed four reaction time trials using a psychomotor test at baseline and at three subsequent rising alcohol-influenced time points. The same test without alcohol was given to

113 subjects (47.2+/-10.8 y of age, 19.3% female subjects) with mild to moderate sleepdisordered breathing. RESULTS: Mean blood alcohol concentrations (BACs) in the alcohol-influenced subjects at baseline and three trials were 0, 0.057, 0.080, and 0.083 g/dL. The sleep-disordered subjects had mean respiratory disturbance indices of 29.2 events per hour of sleep. On all seven reaction time measures, their performance was worse than that of the alcohol subjects when BACs were 0.057 g/dL. For three of the measures, the sleep-disordered subjects performed as poorly as or worse than the alcohol subjects when alcohol levels were 0.080 g/dL. These results could not be explained by sex or age differences. CONCLUSION: The data demonstrate that sleep-disordered subjects in this study (with a mean age of 47 y) with mild to moderate sleep-disordered breathing had worse test reaction time performance parameters than healthy, nonsleepy subjects (with a mean age of 29 y) whose BAC is illegally high for driving a commercial motor vehicle in California. This comparative model points out the potential risks of daytime sleepiness in those with sleepdisordered breathing relative to a culturally accepted standard of impairment

Tongue base reduction with hyoepiglottoplasty: a treatment for severe obstructive sleep apnea. Laryngoscope. 1999 Aug;109(8):1273-80. Chabolle F, Wagner I, Blumen MB, Sequert C, Fleury B, De Dieuleveult T. Division of Otolaryngology-Head and Neck Surgery, Hopital Foch, Suresnes, France.

OBJECTIVE: To describe a surgical procedure for the treatment of severe obstructive sleep apnea syndrome (OSAS), the procedure's indications, and its results. STUDY DESIGN: A retrospective study of 10 male patients with OSAS treated by tongue base reduction with hyoepiglottoplasty (TBRHE) at the Foch Hospital (Suresnes, France) between 1994 and 1997. Patients had a mean body mass index (BMI) of 32 kg/m2, a mean respiratory disturbance index (RDI) of 70 events/h, and a mean minimal oxygen saturation of 78%. They had refused positive airway pressure therapy or wished to discontinue it. METHODS: Subtotal tongue base reduction preceded by lingual neurovascular bundle identification and derouting, epiglottal verticalization, mouth floor horizontalization, and hyoid bone repositioning was performed, associated in some cases to uvulopalatopharyngoplasty (UPPP). Indications were based on a site-related obstruction, on the absence of craniofacial deficiencies, and on the presence of hyolingual abnormalities determined by cephalometry and magnetic resonance imaging. RESULTS: TBRHE associated to UPPP in most cases had an 80% success rate, based on a postoperative RDI below 20 events/h and a reduction of the preoperative RDI of more than 50%. Snoring and excessive daytime sleepiness decreased or disappeared, respectively, in 100% and 90% of the cases. No neurovascular complications occurred. CONCLUSION: TBRHE is a safe procedure for the neurovascular bundle. Associated to a pharyngotomy, it is an effective treatment for severe OSAS attributable to tongue base obstruction. These results require confirmation in a larger series of patients

[Tongue base reduction with hyoid-epiglottoplasty. A surgical alternative in severe sleep apnea syndromes] Ann Otolaryngol Chir Cervicofac. 1998 Dec;115(6):322-31. [Article in French] Chabolle F, Wagner I, Sequert C, Lachiver X, Coquille F, Fleury B, Blumen M. Service d'ORL et de CCF, Hopital Foch, Suresnes.

Introduction : We present preliminary results and indications of tongue base reduction with hyo-epiglottoplasty for the treatment of severe obstructive sleep apnea syndrome (OSAS) due to isolated hyolingual abnormalities. Material and methods : The procedure consists in a subtotal resection of the tongue base after identification and derouting of the lingual neurovascular bundle. Hypopharyngeal enlargement, epiglottis verticalization, floor of the mouth tension and hyoid bone repositioning are also performed during the procedure. Results : 14 severe OSAS male patients (mean apnea-hypopnea index of 71) were treated in our institution from November 1992 to February 1996. Indications were determined after a cephalometric analysis and a magnetic resonance imaging evaluation. Results were evaluated on clinical and polysomnographic criteria. No neurovascular complications occurred. Clinical results were excellent but success rate based on polysomnography was 50%. Conclusion : These preliminary results led us to change some of the steps in the technique. We also identified a predictive factor of success on the cephalometrics: an oropharyngeal area greater than 25 cm2.

[Dilator muscles of the pharynx and their implication in the sleep apnea syndrome of obstructive type. Review of the literature] Ann Otolaryngol Chir Cervicofac. 1998 May;115(2):73-84. [Article in French] Blumen M, Chabolle F, Rabischong E, Rabischong P, Frachet B. Service d'ORL et de Chirurgie Cervico-Faciale, Hopital Avicenne, Bobigny.

Pathophysiology of the obstructive sleep apnea syndrome shows three components: intra and peripharyngeal obstacles, excessive pharyngeal wall compliance and upper airway dilator muscle dysfunction. The intent of this paper is to provide an overview of the anatomy, histology, physiology and pathophysiology of the upper airway dilator muscles based on previously published articles. The upper airway dilator muscles can be separated in three different systems, main and accessory dilators, local and regional. They act in synergy. Their contraction occurs at the beginning of inspiration, thus maintaining opened the pharyngeal lumen through inspiration. Their action is modulated by several chemo or physical stimuli. In some apneic patients, these muscles demonstrate a dysfunction: hyperactivity during wakefulness, electromyogram wave amplitude reduced, delayed contraction during sleep and abnormal response to stimuli. This dysfunction might be due to neuromuscular histological

abnormalities, a "fatigue" phenomenon or a central nervous command abnormality. Current explorations underlining an upper airway dilator muscle dysfunction will enable practitioners to decide which treatment is best and understand therapeutical failures; it will also help develop new therapeutical techniques such as functional electrical stimulation of the hypoglossal nerve/upper airway dilator muscles.

Radiofrequency volumetric tissue reduction of the palate in subjects with sleep-disordered breathing. Chest. 1998 May;113(5):1163-74. Powell NB, Riley RW, Troell RJ, Li K, Blumen MB, Guilleminault C. Stanford University Sleep Disorders and Research Center, Calif, USA.

STUDY OBJECTIVES: To evaluate pain, swallowing, speech, edematous response, tissue shrinkage, sleep, snoring, and safety (energy limits and adverse effects) following radiofrequency (RF) treatment to the palate in 22 subjects with sleep-disordered breathing. DESIGN: This investigation is a prospective nonrandomized study. Polysomnography, radiographic imaging, and infrared thermography, along with questionnaires and visual analog scales, were used to evaluate the effects of RF treatment to the palate. SETTING: Treatments were delivered on an outpatient basis at Stanford University Medical Center. PATIENTS: Twenty-two healthy patients (18 men), with a mean age of 45.3+/-9.1 years, were enrolled. All were snorers seeking treatment and met predetermined criteria: a respiratory disturbance index < or = 15, oxygen saturation > or = 85%, and a complaint of daytime sleepiness. INTERVENTION: RF was delivered to the submucosa of the palate with a custom-fabricated electrode for a mean duration of 141+/-30 s with a mean of 3.6+/-1.2 treatments per patient. Reduction of their snoring scores determined the end point of the study. RESULTS: Neither speech nor swallowing was adversely affected. Pain was of short duration (0 to 48 h) and was controlled with acetaminophen. There were no infections. Although there was documented edema at 24 to 48 h, there were no clinical airway compromises. Polysomnographic data showed improvement in esophageal pressure measurements of the mean nadir and the 95th percentile nadir (p=0.031, p=0.001) respectively, as well as the mean sleep efficiency index (p=0.002). Radiographic imaging showed a mean shrinkage of 5.5+/-3.7 mm (p< or =0.0001). Subjective snoring scores fell by a mean of 77% (8.3+/-1.8 to 1.9+/-1.7, p=0.0001) accompanied by improved mean Epworth sleepiness scores (8.5+/-4.4 to 5.2+/-3.3, p=0.0001). CONCLUSION: The results of this investigation allowed the formulation of safety parameters for RF in this defined population with mild sleep-disordered breathing. There was a documented tissue reduction and improvement in symptoms in all subjects. However, given the small sample size and shortterm follow-up, these results should be confirmed by further investigation

Radiofrequency volumetric reduction of the tongue. A porcine pilot study for the treatment of obstructive sleep apnea syndrome. Chest. 1997 May;111(5):1348-55.

Powell NB, Riley RW, Troell RJ, Blumen MB, Guilleminault C. Stanford University Sleep Disorders and Research Center, Calif., USA.

STUDY OBJECTIVE: To investigate, in an animal model, the feasibility of radiofrequency (RF) volumetric tongue reduction for the future purpose of determining its clinical applications in obstructive sleep apnea syndrome (OSAS). DESIGN: The study was performed in three stages, one in vitro bovine stage and two in vivo porcine stages. The last stage was a prospective investigation with histologic and volumetric analyses to establish outcomes. SETTING: Laboratory and operating room of veterinary research center. PARTICIPANTS: A homogeneous population of porcine animal models, including seven in stage 2 and 12 in stage 3. INTERVENTION: RF energy was delivered by a custom-fabricated needle electrode and RF generator to the tongue tissue of both the in vitro and in vivo models. MEASUREMENTS AND RESULTS: Microultransonic crystals were used to measure three-dimensional changes (volumetric reduction). Lesion size correlated well with increasing RF energy delivery (Sperman correlation coefficient of 0.986; p = 0.0003). Histologic assessments done serially over time (1 h through 3 weeks) showed a well-circumscribed lesion with a normal healing progression and no peripheral damage to nerves. Volumetric analysis documented a very mild initial edematous response that promptly tapered at 24 h. At 10 days after RF, a 26.3% volume reduction was documented at the treatment site (circumscribed by the microultrasonic crystals). CONCLUSION: RF, in a porcine animal model, can safely reduce tongue volume in a precise and controlled manner. Further studies will validate the use of RF in the treatment of OSAS.