XXIV Brazilian Congress on Biomedical Engineering – CBEB 2014 1 SURFACE ELECTROMYOGRAPHY PROTOCOL FOR THE ASSESSMENT OF HUMAN SWALLOWING D. M. Garcia a,b , A. Mapelli a,b , G. A. Folha a,b A. S. Gaido a,b , F. C. P. Valera a,b , L. V. V. Trawitzki a,b and C. M. Felício a,b a Department of Otorhinolaryngology, Ophthalmology, and Head and Neck Surgery. Ribeirao Preto Medical School, University of São Paulo, Brazil b Craniofacial Research Support Center - University of São Paulo email: dmgarcia@fmrp.usp.br Abstract: The surface electromyography (sEMG) application to the study of voice, speech, and swallowing is becoming increasingly popular. A standardized protocol for concomitant sEMG assessment of supra-hyoid muscle activity during deglutition was proposed. The study included 15 healthy volunteers from the community, aged between 21 and 43 years. Simultaneous bilateral sEMG activity from supra-hyoid muscle areas was performed by placing two electrodes. Different swallowing conditions were evaluated: spontaneous swallowing of saliva, voluntarily triggered swallows of 10 ml and 15 ml of water and spontaneous swallowing of a standardized biscuit. The main parameters proposed were: deglutition time, border amplitude, maximum peak amplitude, first maximum peak velocity, maximum peak delay and signal integral. The parameters analyzed in this study were able to compare different consistencies and volumes of the bolus during swallowing. We believe that those parameters will be useful in further researches with patients of different pathologies. Keywords: swallowing, surface electromyography, biomedical signal analysis. Introduction The surface electromyography (sEMG) application to the study of voice, speech, and swallowing is becoming increasingly popular [1]. Specially for assessing the activation of swallowing muscles sEMG methods have already been used [2] with an advantage in relation to the other techniques that is noninvasive, time-saving and enables measurement of muscles activity, providing data to physiologists and clinicians about the physiology of the skeletal muscle during voluntary contractions [3] with no radiation and a negligible discomfort [4]. The sEMG, when used in proper and detailed standardized protocols, with established normative database, can be a useful, reproducible and reliable screening method for the assessment of swallowing disorders [4, 5]. Thus, it will improve future research and clinical applications [1], quantify and regularly monitor the patients with suspected of swallowing disorders [4, 5], proving a simple diagnostic screening [6], because previous data have shown a sEMG activation strictly connected to the swallowing biomechanical events [7]. Although the sEMG has been studied for years in numerous studies, there are important discrepancies between different authors, regarding some of the basic aspects of the act of swallowing common to all subjects [4]. Also, a quantitative and noninvasive evaluation of the entire sequence of the oropharyngeal swallowing process remains to be established, for to promote a differentiating between the values that represents normal and abnormal function [4, 8]. Quantitative studies of swallowing are necessary to gain insight into the mechanisms by which saliva, fluids, and solids of different consistencies are swallowed [9]. This insight might facilitate identification of the specific problems children and adults with dysphagia of different etiology, and can support mechanism-based explanations for dysphagia [9]. Furthermore, sEMG studies of deglutition may be further improved by international standardization, since have been found a large variation in examination techniques, strategies, interpretations, diagnostic criteria and electromyographers [6]. The lack of standard requirements decreases the outcome of this investigation technique significantly. In the case of sEMG evaluation of deglutition the protocol might be based on: protocol application, protocol requirements for diagnostic equipment, protocol technique, protocol tests, normative database and standard analysis [6]. This study presents a standardized protocol for sEMG assessment of supra-hyoid muscle activity during deglutition, and investigates the relationship between parameters and several kinds of deglutition tasks. Materials and methods The study was approved by the local Ethics Committee (HCFMRP-USP 12634/2010) and all subjects gave written informed consent to participate. The study included 15 healthy volunteers from the 1119