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Arie Oliven - One of the best experts on this subject based on the ideXlab platform.

  • relationship between the activity of the genioglossus other peri Pharyngeal Muscles and flow mechanics during wakefulness and sleep in patients with osa and healthy subjects
    Respiratory Physiology & Neurobiology, 2020
    Co-Authors: Ron Oliven, Guy Cohen, Mostafa Somri, Alan R Schwartz, Arie Oliven
    Abstract:

    Abstract Introduction In patients with OSA, substantial increases in genioglossus (GG) activity during hypopneas/apneas usually fail to restore normal airflow. The present study was undertaken to evaluate if this phenomenon can be explained by reduced activation of other peri-Pharyngeal Muscles. Methods We recorded EMGs of the GG and four other peri-Pharyngeal Muscles (accessory dilators, AD), in 8 patients with OSA and 12 healthy subjects, during wakefulness and sleep. Repetitive events of flow limitation were induced during sleep. The events with the highest increases in AD activity were evaluated, to assess if combined activation of both the GG and AD to levels higher than while awake ameliorate airflow reduction during sleep. Results Flow limitation triggered large increases in GG-EMG, but only modest augmentation in AD activity. Nevertheless, phasic EMG activity was present in 40 % of the ADs during sleep. In multiple events, increases of both GG and AD activity to levels substantially higher than while awake were not associated with improvement in airflow. Conclusions We conclude that sleep-induced reduction in AD response to airway obstruction cannot completely explain the failure of upper airway dilators to maintain Pharyngeal patency. We speculate that reduction in dilator muscle efficacy may be due to the alterations in motor units recruitment patterns during sleep.

  • Spectral analysis of peri-Pharyngeal Muscles' EMG in patients with OSA and healthy subjects.
    Respiratory physiology & neurobiology, 2018
    Co-Authors: Ron Oliven, Guy Cohen, Mostafa Somri, Alan R Schwartz, Arie Oliven
    Abstract:

    Abstract Introduction In addition to dyscoordination of upper airway dilator Muscles activity, sleep may also alter the pattern of intra-muscular activation of single motor units (SMUs). Such changes should be identifiable by a state dependent change in EMG power spectrum, i.e., a shift in centroid frequency (ƒc) during sleep. Methods EMGs of the genioglossus and four other peri-Pharyngeal Muscles were recorded in OSA patients (n = 8), age-matched healthy subjects (n = 7), and 5 young healthy subjects, and ƒc was calculated for wakefulness and sleep periods. Results ƒc decreased with the onset of sleep and returned to baseline levels after arousal. ƒc of all Muscles decreased similarly and significantly during sleep in the OSA and the age-matched healthy subjects, but not in the young subjects. Conclusions The pattern of decrease in ƒc is compatible with altered synchronization of SMUs during sleep. We speculate that these changes may contribute to the failure of dilator Muscles to improve flow limitation during sleep in older subjects.

  • Peri-Pharyngeal muscle response to inspiratory loading: comparison of patients with OSA and healthy subjects.
    Journal of Sleep Research, 2018
    Co-Authors: Ron Oliven, Guy Cohen, Mostafa Somri, Alan R Schwartz, Arie Oliven
    Abstract:

    : Upper airway patency to airflow and the occurrence of obstructive sleep apnea involve a complex interplay between Pharyngeal anatomy and synergic co-activation of peri-Pharyngeal Muscles. In previous studies we observed large differences in the response to sleep-associated flow limitation between the genioglossus and other (non-GG) peri-Pharyngeal Muscles. We hypothesized that similar differences are present also during wakefulness. In the present study we compared the response to inspiratory loading of the genioglossus electromyogram and four other peri-Pharyngeal Muscles. Studies were performed in eight obstructive sleep apnea patients, seven age-matched healthy subjects and five additional younger subjects. Electromyogram activity was evaluated over a range of negative oesophageal pressures and expressed as % of maximal electromyograms. In healthy subjects, the slope response to inspiratory loading (electromyogram/pressures) was similar for the genioglossus and non-GG Muscles studied. However, the electromyogram responses were significantly higher in the young subjects compared with older subjects. In contrast, in the obstructive sleep apnea patients, the electromyogram/pressure response of the non-GG Muscles was similar to that of the age-matched healthy subjects, whereas the slope response of the genioglossus electromyogram was significantly higher than non-GG Muscles. We conclude that both age and the presence of obstructive sleep apnea affect the response of peri-Pharyngeal Muscles to inspiratory loading. In patients with obstructive sleep apnea the genioglossus seems to compensate for mechanical disadvantages, but non-GG Muscles apparently are not included in this neuromuscular compensatory mechanism. Our current and previous findings suggest that attempts to improve obstructive sleep apnea with myofunctional therapy should put added emphasis on the training of non-GG Muscles.

Eric Verin - One of the best experts on this subject based on the ideXlab platform.

  • Sensory Transcutaneous Electrical Stimulation Improves Post-Stroke Dysphagic Patients
    Dysphagia, 2010
    Co-Authors: Syrine Gallas, Jean Paul Marie, Anne Marie Leroi, Eric Verin
    Abstract:

    OroPharyngeal dysphagia is frequent in stroke patients and increases mortality, mainly because of pulmonary complications. We hypothesized that sensitive transcutaneous electrical stimulation applied submentally during swallowing could help rehabilitate post-stroke oroPharyngeal dysphagia by improving cortical sensory motor circuits. Eleven patients were recruited for the study (5 females, 68 ± 11 years). They all suffered from recent oroPharyngeal dysphagia (>eight weeks) induced by a hemispheric ( n  = 7) or brainstem ( n  = 4) stroke, with Pharyngeal residue and/or laryngeal aspiration diagnosed by videofluoroscopy. Submental electrical stimulations were performed for 1 h every day for 5 days (electrical trains: 5 s every minute, 80 Hz, under motor threshold). During the electrical stimulations, the patients were asked to swallow one teaspoon of paste or liquid. Swallowing was evaluated before and after the week of stimulations using a dysphagia handicap index questionnaire, videofluoroscopy, and cortical mapping of Pharyngeal Muscles. The results of the questionnaire showed that oroPharyngeal dysphagia symptoms had improved ( p  

Ron Oliven - One of the best experts on this subject based on the ideXlab platform.

  • relationship between the activity of the genioglossus other peri Pharyngeal Muscles and flow mechanics during wakefulness and sleep in patients with osa and healthy subjects
    Respiratory Physiology & Neurobiology, 2020
    Co-Authors: Ron Oliven, Guy Cohen, Mostafa Somri, Alan R Schwartz, Arie Oliven
    Abstract:

    Abstract Introduction In patients with OSA, substantial increases in genioglossus (GG) activity during hypopneas/apneas usually fail to restore normal airflow. The present study was undertaken to evaluate if this phenomenon can be explained by reduced activation of other peri-Pharyngeal Muscles. Methods We recorded EMGs of the GG and four other peri-Pharyngeal Muscles (accessory dilators, AD), in 8 patients with OSA and 12 healthy subjects, during wakefulness and sleep. Repetitive events of flow limitation were induced during sleep. The events with the highest increases in AD activity were evaluated, to assess if combined activation of both the GG and AD to levels higher than while awake ameliorate airflow reduction during sleep. Results Flow limitation triggered large increases in GG-EMG, but only modest augmentation in AD activity. Nevertheless, phasic EMG activity was present in 40 % of the ADs during sleep. In multiple events, increases of both GG and AD activity to levels substantially higher than while awake were not associated with improvement in airflow. Conclusions We conclude that sleep-induced reduction in AD response to airway obstruction cannot completely explain the failure of upper airway dilators to maintain Pharyngeal patency. We speculate that reduction in dilator muscle efficacy may be due to the alterations in motor units recruitment patterns during sleep.

  • Spectral analysis of peri-Pharyngeal Muscles' EMG in patients with OSA and healthy subjects.
    Respiratory physiology & neurobiology, 2018
    Co-Authors: Ron Oliven, Guy Cohen, Mostafa Somri, Alan R Schwartz, Arie Oliven
    Abstract:

    Abstract Introduction In addition to dyscoordination of upper airway dilator Muscles activity, sleep may also alter the pattern of intra-muscular activation of single motor units (SMUs). Such changes should be identifiable by a state dependent change in EMG power spectrum, i.e., a shift in centroid frequency (ƒc) during sleep. Methods EMGs of the genioglossus and four other peri-Pharyngeal Muscles were recorded in OSA patients (n = 8), age-matched healthy subjects (n = 7), and 5 young healthy subjects, and ƒc was calculated for wakefulness and sleep periods. Results ƒc decreased with the onset of sleep and returned to baseline levels after arousal. ƒc of all Muscles decreased similarly and significantly during sleep in the OSA and the age-matched healthy subjects, but not in the young subjects. Conclusions The pattern of decrease in ƒc is compatible with altered synchronization of SMUs during sleep. We speculate that these changes may contribute to the failure of dilator Muscles to improve flow limitation during sleep in older subjects.

  • Peri-Pharyngeal muscle response to inspiratory loading: comparison of patients with OSA and healthy subjects.
    Journal of Sleep Research, 2018
    Co-Authors: Ron Oliven, Guy Cohen, Mostafa Somri, Alan R Schwartz, Arie Oliven
    Abstract:

    : Upper airway patency to airflow and the occurrence of obstructive sleep apnea involve a complex interplay between Pharyngeal anatomy and synergic co-activation of peri-Pharyngeal Muscles. In previous studies we observed large differences in the response to sleep-associated flow limitation between the genioglossus and other (non-GG) peri-Pharyngeal Muscles. We hypothesized that similar differences are present also during wakefulness. In the present study we compared the response to inspiratory loading of the genioglossus electromyogram and four other peri-Pharyngeal Muscles. Studies were performed in eight obstructive sleep apnea patients, seven age-matched healthy subjects and five additional younger subjects. Electromyogram activity was evaluated over a range of negative oesophageal pressures and expressed as % of maximal electromyograms. In healthy subjects, the slope response to inspiratory loading (electromyogram/pressures) was similar for the genioglossus and non-GG Muscles studied. However, the electromyogram responses were significantly higher in the young subjects compared with older subjects. In contrast, in the obstructive sleep apnea patients, the electromyogram/pressure response of the non-GG Muscles was similar to that of the age-matched healthy subjects, whereas the slope response of the genioglossus electromyogram was significantly higher than non-GG Muscles. We conclude that both age and the presence of obstructive sleep apnea affect the response of peri-Pharyngeal Muscles to inspiratory loading. In patients with obstructive sleep apnea the genioglossus seems to compensate for mechanical disadvantages, but non-GG Muscles apparently are not included in this neuromuscular compensatory mechanism. Our current and previous findings suggest that attempts to improve obstructive sleep apnea with myofunctional therapy should put added emphasis on the training of non-GG Muscles.

John C. Keifer - One of the best experts on this subject based on the ideXlab platform.

  • Neurophysiological intraoperative monitoring of the glossoPharyngeal nerve: technical case report.
    Neurosurgery, 2008
    Co-Authors: Aatif M. Husain, David R. Wright, Bw Stolp, Allan H. Friedman, John C. Keifer
    Abstract:

    OBJECTIVE: Neurophysiological intraoperative monitoring of the glossoPharyngeal nerve has been performed only with needle electrodes inserted into the Pharyngeal Muscles or soft palate. We describe a noninvasive method of monitoring this cranial nerve. METHODS: A 30-year-old man who presented with headache, as well as speech and swallowing difficulty, underwent surgical resection of a right vagus nerve schwannoma. Neurophysiological intraoperative monitoring of multiple lower cranial nerves, including the glossoPharyngeal and vagus nerves, was performed. RESULTS: The glossoPharyngeal nerve was monitored with an adhesive surface electrode mounted on the cuff of a laryngeal mask airway, and the vagus nerve was monitored with a similar electrode mounted on the endotracheal tube. Successful monitoring allowed separation of the glossoPharyngeal nerve from the tumor, and there was no postoperative swallowing deficit. CONCLUSION: Monitoring of the glossoPharyngeal nerve with surface electrodes is possible and reliable, but it must be combined with vagus nerve monitoring.

  • Neurophysiological intraoperative monitoring of the glossoPharyngeal nerve: technical case report.
    Neurosurgery, 2008
    Co-Authors: Aatif M. Husain, David R. Wright, Bw Stolp, Allan H. Friedman, John C. Keifer
    Abstract:

    Neurophysiological intraoperative monitoring of the glossoPharyngeal nerve has been performed only with needle electrodes inserted into the Pharyngeal Muscles or soft palate. We describe a noninvasive method of monitoring this cranial nerve. A 30-year-old man who presented with headache, as well as speech and swallowing difficulty, underwent surgical resection of a right vagus nerve schwannoma. Neurophysiological intraoperative monitoring of multiple lower cranial nerves, including the glossoPharyngeal and vagus nerves, was performed. The glossoPharyngeal nerve was monitored with an adhesive surface electrode mounted on the cuff of a laryngeal mask airway, and the vagus nerve was monitored with a similar electrode mounted on the endotracheal tube. Successful monitoring allowed separation of the glossoPharyngeal nerve from the tumor, and there was no postoperative swallowing deficit. Monitoring of the glossoPharyngeal nerve with surface electrodes is possible and reliable, but it must be combined with vagus nerve monitoring.

P Nolan - One of the best experts on this subject based on the ideXlab platform.

  • 14: A reassessment of the respiratory function of upper airway Muscles
    Journal of Anatomy, 2002
    Co-Authors: P Nolan
    Abstract:

    The mammalian pharynx is a musculomembranous tube ideally adapted to ingesting a varied diet or modulating and modifying the acoustic output of the larynx. However, as an element of the respiratory tract, the pharynx has little bony or cartilaginous support, leaving the airway susceptible to collapse. Narrowing or obstruction of the Pharyngeal airway is normally prevented by the action of skeletal Muscles located within or attached to the Pharyngeal wall. It has been assumed that the Muscles responsible for maintaining airway patency are those which act to widen the airspace, such as the genioglossus and palatoglossus, and there has been considerable interest in the neural control of these airway dilator Muscles. Muscles which act to narrow the airway, such as tongue retractor and Pharyngeal constrictor Muscles, may play a role in regulating expiratory airflow but otherwise were not thought to have a major respiratory function. However recent findings suggest that these Muscles, by stiffening the wall of the pharynx and immobilising the tongue, may be important in stabilising the airway and preventing obstruction. The effect of these Muscles on Pharyngeal collapsibility may depend upon the activity of other Pharyngeal Muscles and the initial resting size of the airspace. Furthermore it remains to be seen whether there are differences in respiratory function between different components of the Pharyngeal constrictor apparatus. Developing a detailed understanding of the motor and reflex control of Pharyngeal Muscles and the biomechanical result of their activation promises to be an important, complex and challenging problem.