Electrodiagnostic methods for neurogenic dysphagia

Department of Clinical Neurophysiology, Medical School Hospital, Ege University Bornova, Izmir, Turkey.
Electroencephalography and Clinical Neurophysiology 09/1998; 109(4):331-40. DOI: 10.1016/S0924-980X(98)00027-7
Source: PubMed


Swallowing mechanisms and neurogenic dysphagia have not been systematically studied by the EMG technique. It is desirable to evaluate neurogenic dysphagia for diagnostic and possibly for therapeutic purposes using electrophysiological methods.
The following methods were described: mechanical upward/downward movements of the larynx were detected using a piezoelectric sensor, while submental integrated EMG activity was recorded during dry and wet swallowing. The EMG activity of cricopharyngeal muscle of the upper oesophageal sphincter was also recorded in some normal subjects and patients. Piecemeal deglutition and the dysphagia limit were determined in all patients to detect dysphagia objectively. In this study 75 normal subjects and 177 neurological patients with various degrees of dysphagia were investigated.
Voluntarily triggered oropharyngeal swallowing was commonly pathological in the majority of patients, with or without overt dysphagia. The dysphagia limit appeared to be an objective measure of the degree of dysphagia in more than 90% of patients. Pathophysiological mechanisms were different in at least three groups of patients with neurogenic dysphagia. In the group of patients with muscular disorders, laryngeal elevators were involved while the CP-sphincter was intact. The second group included patients with the clinical signs of corticobulbar fibre involvement such as amyotrophic lateral sclerosis and pseudobulbar palsy. In these patients, there was incoordination between paretic laryngeal elevators and hyperreflexic CP-sphincter. In the third group (patients with Parkinson's disease), the swallowing reflex was delayed and prolonged.
EMG methods described in the present study are very useful for the diagnosis of neurogenic dysphagia, objectively and quickly. They are important to understand the physiological mechanisms for deglutition and its disorders.

Download full-text


Available from: Cumhur Ertekin
  • Source
    • "The methods for the evaluation of dysphagia were previously described (Ertekin et al., 1998a). During the examination, the seated patient is instructed to hold his/her head in a neutral upright position. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Objective Neurogenic dysphagia (ND) is a prevalent condition that accounts for significant mortality and morbidity worldwide. Screening and follow-up is critical for early diagnosis and management which can mitigate its complications and be cost-saving. Aims of this study are to provide a comprehensive investigation of the dysphagia limit in a large diverse cohort and to provide a longitudinal assessment of dysphagia in in a subset of subjects. Methods We developed a quantitative and non-invasive method for objective assessment of dysphagia by using laryngeal sensor and submental electromyography. Dysphagia Limit (DL) is the volume at which second or more swallows become necessary to swallow the whole amount of bolus. This study represents 17 years experience with the DL approach in assessing ND in a cohort of 1,278 adult subjects consisting of 292 healthy controls, 784 patients with dysphagia and 202 patients without dysphagia. One hundred and ninety two of all patients were also re-evaluated longitudinally over a period of 1-19 months. Results DL has 92% sensitivity; 91% specificity; 94% positive predictive value and 88% negative predictive value with an accuracy of 0.92. Patients with ALS, stroke and movement disorders have the highest sensitivity (85-97%) and positive predictive value (90-99%). The clinical severity of dysphagia has significant negative correlation with DL (r=-0.67, p<0.0001). Conclusions We propose the DL as a reliable, quick, non-invasive, quantitative test to detect and follow both clinical and subclinical dysphagia and it can be performed in an EMG laboratory. Significance Our study provides specific quantitative features of DL test that can be readily utilized by the neurologic community and nominates DL as an objective and robust method to evaluate dysphagia in a wide range of neurologic conditions.
    Full-text · Article · Jul 2014 · Clinical Neurophysiology
  • Source
    • "The individual results showed that there were two kind of responses of CP-sphincter during swallowing. In three patients with PM/DM, the CP-EMG pause was shorter remarkably than the lower limit of normal controls (301 ms, mean−2.5 S.D.) while in the other two patients, the CP-EMG pause was longer than the upper limits of normal controls (681 ms, mean + 2.5 S.D.) [12] [16] (Fig. 3). Therefore, the abnormalities of CP-sphincter EMG was found in 5 out of 10 patients investigated (50%). "
    [Show abstract] [Hide abstract]
    ABSTRACT: The nature of the oropharyngeal dysphagia in polymyositis/dermatomyositis (PM/DM) has been investigated by EMG methods. Nineteen patients with PM/DM were studied. The oropharyngeal phase of swallowing was evaluated by the electrophysiological methods measuring the laryngeal relocation time, pharyngeal transit time and the triggering of the pharyngeal phase of swallowing reflex. The EMG of cricopharyngeal muscle of the upper esophageal sphincter was also recorded in 10 patients. The patients have been compared with a group of 22 healthy controls matched with age and gender. Dysphagia limit was also measured for all patients and control subjects. Fourteen out of 19 patients could not swallow 20 ml or less amount of water at one go and divided the bolus into two or more pieces (piecemeal deglutition) in comparison to normal subjects. In PM/DM patients, the triggering of the swallowing reflex for the voluntarily initiated swallow was normal while the pharyngeal phase of swallowing was significantly prolonged. The cricopharyngeal sphincter muscle EMG demonstrated severe abnormalities in halves of the patients investigated. These findings demonstrated the weakness of the striated oropharyngeal muscles. Cricopharyngeal sphincter muscle was affected less frequently and showed either hyperreflexic or hyporeflexic states during swallowing. It is concluded that the pharyngeal stage of oropharyngeal swallowing is mainly involved in patients with PM/DM.
    Full-text · Article · Jan 2005 · Clinical Neurology and Neurosurgery
  • Source
    • "Despite this, dysphagia appears to be mild and the incidence is lower in such anterior horn cell disorders. Similarly, it has been shown that in dysphagic patients with myasthenia gravis and polymyositis, triggering of the pharyngeal phase of swallowing is not very severely disturbed, or may even be normal as judged from the electrophysiological results (Ertekin et al., 1998). In these patients, the relocation time of larynx is often prolonged. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Parkinson’s disease (PD) is a chronic, neurodegenerative movement disorder that typically affects elderly patients. Swallowing disorders are highly prevalent in PD and can have grave consequences, including pneumonia, malnutrition, dehydration and mortality. Neurogenic dysphagia in PD can manifest with both overt clinical symptoms or silent dysphagia. Regardless, early diagnosis and objective follow-up of dysphagia in PD is crucial for timely and appropriate care for these patients. In this review, we provide a comprehensive summary of the electrophysiological methods that can be used to objectively evaluate dysphagia in PD. We discuss the electrophysiological abnormalities that can be observed in PD, their clinical correlates and the pathophysiology underlying these findings.
    Full-text · Chapter · Dec 2004
Show more