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Surface electromyography as a screening method for evaluation of dysphagia and odynophagia.

Vaiman M, Eviatar E - Head Face Med (2009)

Bottom Line: Patients suspected of having swallowing disorders, could highly benefit from simple diagnostic screening before being referred to specialist evaluations.SEMG is compared with other techniques in terms of cost, timing, involvement of radiation, etc.With standardization of the technique and an established normative database, sEMG might serve as a reliable screening method for optimal patient management but cannot serve for proper investigation of neurogenic dysphagia.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Otolaryngology, Assaf Harofe Medical Center, Affiliated to Sackler Faculty of Medicine, Tel Aviv University, Israel. vaimed@yahoo.com

ABSTRACT

Objective: Patients suspected of having swallowing disorders, could highly benefit from simple diagnostic screening before being referred to specialist evaluations. The article analyzes various instrumental methods of dysphagia assessment, introduces surface electromyography (sEMG) to carry out rapid assessment of such patients, and debates proposed suggestions for sEMG screening protocol in order to identify abnormal deglutition.

Data sources: Subject related books and articles from 1813 to 2007 were obtained through library search, MEDLINE (1949-2007) and EMBASE (1975-2007).

Methods: Specifics steps for establishing the protocol for applying the technique for screening purposes (e.g., evaluation of specific muscles), the requirements for diagnostic sEMG equipment, the sEMG technique itself, and defining the tests suitable for assessing deglutition (e.g., saliva, normal, and excessive swallows and uninterrupted drinking of water) are presented in detail. SEMG is compared with other techniques in terms of cost, timing, involvement of radiation, etc.

Results: According to the published data, SEMG of swallowing is a simple and reliable method for screening and preliminary differentiation among dysphagia and odynophagia of various origins. This noninvasive radiation-free examination has a low level of discomfort, and is simple, time-saving and inexpensive to perform. The major weakness of the method seems to be inability for precise diagnostic of neurologically induced dysphagia.

Conclusion: With standardization of the technique and an established normative database, sEMG might serve as a reliable screening method for optimal patient management but cannot serve for proper investigation of neurogenic dysphagia.

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Related in: MedlinePlus

Stages of the normal swallow (reflex part). A – final oral stage, B – pharyngeal stage, C – beginning of oesophageal stage. In normal deglutition the INF record is the lowest and less informative (eliminated here for clarity).
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Figure 2: Stages of the normal swallow (reflex part). A – final oral stage, B – pharyngeal stage, C – beginning of oesophageal stage. In normal deglutition the INF record is the lowest and less informative (eliminated here for clarity).

Mentions: A typical single water swallow of a healthy individual is observed graphically at the rectified and low-pass filtered SEMG as a normal wave with upward deflections and a sharp apex when recorded from the MS, SUB and, to lesser extent, from INF locations [31-36]. The reflex part of a swallow is recorded from the MS, SUB and INF locations, while the conscious part can be recorded from the OO and MS locations. This upward stroke, as recorded from the MS, SUB and much less from INF locations, can be divided into three main parts (Fig. 2). In swallowing water, the first part (A) is usually seen as a mild elevation of the line and represents the final oral stage of a swallow which occurs when the tongue is moved so as to squeeze the liquid volume against the hard palate. Submental muscles and the masseter muscle support the tongue-induced pressure. At this stage, the automatic reflexive motion of swallowing is triggered. When the reflex is initiated, the second stage, the pharyngeal, begins. It is seen as a rapid voltage line elevation on the second part of the wave (B). When the bolus is finally passed into the oesophagus by the relaxation of the sphincter at the cricopharyngeal juncture, the third part (C) of the stroke is seen as a rapid descent of the SEMG line when the muscles relax and their voltage decreases. This part indicates the initiation of the oesophageal stage of swallowing. In all healthy people during the tests, the mean electric activity at SUB location is 30–50% higher than the activity at MS and INF locations. Amplitude of the OO line is usually significantly higher than the SUB and especially with the MS and INF graphic lines. Being under conscious control, the oral phase of swallowing is very variable and should be taken into consideration with caution during the evaluation of the recordings. By the same reason, the data taken from the OO electrode location is the least informative and safely can be omitted if we deal with pharyngo-laryngeal or oesophageal problems rather than with oro-maxillo-facial.


Surface electromyography as a screening method for evaluation of dysphagia and odynophagia.

Vaiman M, Eviatar E - Head Face Med (2009)

Stages of the normal swallow (reflex part). A – final oral stage, B – pharyngeal stage, C – beginning of oesophageal stage. In normal deglutition the INF record is the lowest and less informative (eliminated here for clarity).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2654879&req=5

Figure 2: Stages of the normal swallow (reflex part). A – final oral stage, B – pharyngeal stage, C – beginning of oesophageal stage. In normal deglutition the INF record is the lowest and less informative (eliminated here for clarity).
Mentions: A typical single water swallow of a healthy individual is observed graphically at the rectified and low-pass filtered SEMG as a normal wave with upward deflections and a sharp apex when recorded from the MS, SUB and, to lesser extent, from INF locations [31-36]. The reflex part of a swallow is recorded from the MS, SUB and INF locations, while the conscious part can be recorded from the OO and MS locations. This upward stroke, as recorded from the MS, SUB and much less from INF locations, can be divided into three main parts (Fig. 2). In swallowing water, the first part (A) is usually seen as a mild elevation of the line and represents the final oral stage of a swallow which occurs when the tongue is moved so as to squeeze the liquid volume against the hard palate. Submental muscles and the masseter muscle support the tongue-induced pressure. At this stage, the automatic reflexive motion of swallowing is triggered. When the reflex is initiated, the second stage, the pharyngeal, begins. It is seen as a rapid voltage line elevation on the second part of the wave (B). When the bolus is finally passed into the oesophagus by the relaxation of the sphincter at the cricopharyngeal juncture, the third part (C) of the stroke is seen as a rapid descent of the SEMG line when the muscles relax and their voltage decreases. This part indicates the initiation of the oesophageal stage of swallowing. In all healthy people during the tests, the mean electric activity at SUB location is 30–50% higher than the activity at MS and INF locations. Amplitude of the OO line is usually significantly higher than the SUB and especially with the MS and INF graphic lines. Being under conscious control, the oral phase of swallowing is very variable and should be taken into consideration with caution during the evaluation of the recordings. By the same reason, the data taken from the OO electrode location is the least informative and safely can be omitted if we deal with pharyngo-laryngeal or oesophageal problems rather than with oro-maxillo-facial.

Bottom Line: Patients suspected of having swallowing disorders, could highly benefit from simple diagnostic screening before being referred to specialist evaluations.SEMG is compared with other techniques in terms of cost, timing, involvement of radiation, etc.With standardization of the technique and an established normative database, sEMG might serve as a reliable screening method for optimal patient management but cannot serve for proper investigation of neurogenic dysphagia.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Otolaryngology, Assaf Harofe Medical Center, Affiliated to Sackler Faculty of Medicine, Tel Aviv University, Israel. vaimed@yahoo.com

ABSTRACT

Objective: Patients suspected of having swallowing disorders, could highly benefit from simple diagnostic screening before being referred to specialist evaluations. The article analyzes various instrumental methods of dysphagia assessment, introduces surface electromyography (sEMG) to carry out rapid assessment of such patients, and debates proposed suggestions for sEMG screening protocol in order to identify abnormal deglutition.

Data sources: Subject related books and articles from 1813 to 2007 were obtained through library search, MEDLINE (1949-2007) and EMBASE (1975-2007).

Methods: Specifics steps for establishing the protocol for applying the technique for screening purposes (e.g., evaluation of specific muscles), the requirements for diagnostic sEMG equipment, the sEMG technique itself, and defining the tests suitable for assessing deglutition (e.g., saliva, normal, and excessive swallows and uninterrupted drinking of water) are presented in detail. SEMG is compared with other techniques in terms of cost, timing, involvement of radiation, etc.

Results: According to the published data, SEMG of swallowing is a simple and reliable method for screening and preliminary differentiation among dysphagia and odynophagia of various origins. This noninvasive radiation-free examination has a low level of discomfort, and is simple, time-saving and inexpensive to perform. The major weakness of the method seems to be inability for precise diagnostic of neurologically induced dysphagia.

Conclusion: With standardization of the technique and an established normative database, sEMG might serve as a reliable screening method for optimal patient management but cannot serve for proper investigation of neurogenic dysphagia.

Show MeSH
Related in: MedlinePlus