Identificación de la Señal Mioeléctrica del Intestino Delgado Registrada en Superficie Externa Abdominal. Comparativa con Registros Internos

[EN] Intestinal motility is responsible for the functions of segmentation, mixing and transport of the chime poured from the stomach. These functions are of main importance in the processes of nutrients digestion and absorption. Intestinal contractile activity is determined by the myoelectrical activity of intestinal muscular layers. Precisely, intestinal myoelectrical activity, which is also called electroenterogram (EEnG), is the result of two components: a low frequency component (slow wave, SW) that is always present and a high frequency component (spike bursts, SB) which is associated with bowel contractions. Despite of the diagnostic significance of internal recordings of EEnG, clinical application of this technique is limited due to its invasiveness. Thus, surface recording of EEnG could be a solution for non-invasive monitoring of intestinal motility. The aim of this Ph.D. Thesis is the recording of surface electroenterogram and the identification of slow wave and spike bursts activity in order to quantify bowel motor activity in dogs. We conducted simultaneous recordings of IMA in bowel serosa and on abdominal surface of Beagle dogs in fast state. Both signals were analyzed in spectral domain and a frequency band for slow wave and spike bursts energy were determined. Likewise, the effects of abdominal layers and of possible interferences on surface recording of EEnG were also studied. For this purpose it was necessary to define new signal-to-interference and attenuation functions. We calculated different spectral parameters of surface EEnG that quantify presence and intensity of SB taking into consideration the attenuation behavior of abdominal layers and interference effects. These parameters have shown a strong correlation with bowel contractile activity. The research about surface EEnG is complemented with an analysis of signal dynamics throughout the pattern of bowel motor activity in fast state. Stationarity of the signal was evaluated in every period of contractile activity with different window-lengths. The study finishes with the definition of an algorithm that provides a variable window-length, adapting EEnG analysis to the spectral content of signal at every moment. This permits the generation of a fast non-invasive index of bowel contractile activity for future real-time applications. Three main conclusions can be deduced out of the obtained results: - It is possible to identify both bowel’s slow wave and spike bursts activity on surface recordings of EEnG. - Quantification of SB activity on surface EEnG allows non-invasive monitoring of small bowel mechanical activity. - It has been developed a new adaptive analysis method that improves intestinal motility indexes based in traditional techniques as it considers non-stationarity of EEnG.[ES] La motilidad intestinal es responsable de las funciones de segmentación, mezcla y transporte del quimo vertido desde el estómago. Estas funciones son fundamentales en los procesos de digestión y absorción de nutrientes. La actividad contráctil intestinal está determinada por la actividad mioeléctrica de las capas musculares intestinales. Concretamente, la actividad mioeléctrica intestinal, también denominada electroenterograma (EEnG), es el resultado de dos componentes: una componente de baja frecuencia que está siempre presente (onda lenta, OL); y una componente de alta frecuencia (potenciales rápidos de acción o spike bursts, SB) que está asociada directamente a las contracciones intestinales. A pesar del valor diagnóstico de los registros internos del EEnG, su aplicación clínica está limitada debido a su carácter invasivo. Por tanto, el registro en superficie del EEnG podría ser una solución a la monitorización no-invasiva de la motilidad intestinal. El objetivo de la presente tesis doctoral es el registro del electroenterograma de superficie y la identificación de la actividad de la onda lenta y de los spike bursts para la cuantificación no-invasiva de la actividad contráctil intestinal en perros. Se han llevado a cabo registros simultáneos del EEnG en la serosa intestinal y en superficie abdominal de perros Beagle en estado de ayunas. Ambas señales se han analizado en el dominio espectral para la determinación de los rangos de frecuencia en que se localiza la energía tanto de la OL como de los SB. Asimismo se ha estudiado la influencia de las capas abdominales y de posibles interferencias sobre el registro externo. Para ello ha sido necesario definir las funciones señal-interferencia y de atenuación, inéditas hasta la fecha. Teniendo en cuenta estos efectos de atenuación e interferencia, se han calculado distintos parámetros espectrales del EEnG de superficie que cuantifican la existencia e intensidad de SB. Estos parámetros han mostrado una elevada correlación con el grado de actividad contráctil intestinal interno. La investigación sobre el EEnG de superficie se complementa con un análisis de la dinámica de la señal a lo largo del patrón de motilidad intestinal en ayunas. Se ha valorado el grado de estacionariedad de la señal en cada estado de actividad contráctil para distintos anchos de ventana. El estudio finaliza con la definición de un algoritmo que proporciona un ancho de ventana variable, adaptando el análisis del EEnG al contenido espectral de la señal en cada momento. Esto permite generar un indicador no-invasivo de actividad contráctil intestinal, rápido de obtener, para futuras aplicaciones en tiempo real. De los resultados obtenidos se extraen tres conclusiones fundamentales: - Es posible identificar tanto la actividad de la onda lenta intestinal como la actividad de los potenciales rápidos de acción (SB) en el registro del EEnG de superficie. - La cuantificación de la actividad de los SB del EEnG de superficie permite la monitorización no invasiva de la actividad mecánica del intestino delgado. - Se ha desarrollado un método de análisis adaptativo que mejora los índices de motilidad intestinal basado en técnicas tradicionales, ya que tiene en cuenta la no estacionariedad del EEnG.[CA] La motilitat intestinal és responsable de les funcions de segmentació, mixtió i transport del quimo abocat des de l'estómac. Aquestes funcions són fonamentals en els processos de digestió i absorció de nutrients. L'activitat contràctil intestinal està determinada per l'activitat mioelèctrica de les capes musculars intestinals. Concretament, l'activitat mioelèctrica intestinal, també denominada electroenterograma (EEnG), és el resultat de dos components: una component de baixa freqüència que està sempre present (ona lenta, OL); i una component d'alta freqüència (potencials ràpids d'acció o spike bursts, SB) que està associada directament a les contraccions intestinals. A pesar del valor diagnòstic dels registres interns del EEnG, la seva aplicació clínica està limitada a causa de el seu caràcter invasiu. Per tant, el registre en superfície del EEnG podria ser una solució al monitoratge no-invasiu de la motilitat intestinal. L'objectiu de la present tesi doctoral és el registre de l’electroenterograma de superfície i la identificació de l'activitat de l'ona lenta i dels spike bursts per a la quantificació no-invasiva de l'activitat contràctil intestinal en gos. S'han portat a terme registres simultanis del EEnG en la serosa intestinal i en superfície abdominal de gossos Beagle en estat de dejunes. Ambdues senyals s'han analitzat en el domini espectral per a la determinació dels rangs de freqüència on es localitza l'energia tant de la OL com dels SB. Així mateix s'ha estudiat la influència de les capes abdominals i de possibles interferències sobre el registre extern. Per a això ha estat necessari desenvolupar les funcions senyal-interferència i d'atenuació inèdites fins a la data. Tenint en compte aquests efectes d'atenuació i interferència, s'han definit distints paràmetres espectrals del EEnG de superfície que quantifiquen l'existència i intensitat de SB. Aquests paràmetres han mostrat una elevada correlació amb el grau d'activitat contràctil intestinal intern. La investigació sobre el EEnG de superfície es completa amb una anàlisi de la dinàmica del senyal al llarg del patró de motilitat intestinal en dejú. S'ha valorat el grau de estacionarietat del senyal en cada estat d'activitat contràctil per a distints amples de finestra. L'estudi finalitza amb la definició d'un algorisme que proporciona un ample de finestra variable, adaptant l'anàlisi del EEnG al contingut espectral del senyal a cada moment. Això permet generar un indicador no-invasiu d'activitat contràctil intestinal, ràpid d'obtenir, per a futures aplicacions en temps real. Els resultats obtinguts permeten extreure tres conclusions fonamentals: - És possible identificar tant l'activitat de l'ona lenta intestinal com l'activitat dels potencials ràpids d’acció (SB) en el registre del EEnG de superfície. - La quantificació de l'activitat dels SB del EEnG de superfície permet el monitoratge no invasiu de l'activitat mecànica de l'intestí prim. - S'ha desenvolupat un mètode d'anàlisi adaptatiu que millora els índexs de motilitat intestinal basat en tècniques tradicionals, ja que té en compte la no-estacionarietat del EEnG.Garcia Casado, FJ. (2005). Identificación de la Señal Mioeléctrica del Intestino Delgado Registrada en Superficie Externa Abdominal. Comparativa con Registros Internos [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/135956TESI

A Flexible Multiring Concentric Electrode for Non-Invasive Identification of Intestinal Slow Waves

[EN] Developing new types of optimized electrodes for specific biomedical applications can substantially improve the quality of the sensed signals. Concentric ring electrodes have been shown to provide enhanced spatial resolution to that of conventional disc electrodes. A sensor with different electrode sizes and configurations (monopolar, bipolar, etc.) that provides simultaneous records would be very helpful for studying the best signal-sensing arrangement. A 5-pole electrode with an inner disc and four concentric rings of different sizes was developed and tested on surface intestinal myoelectrical recordings from healthy humans. For good adaptation to a curved body surface, the electrode was screen-printed onto a flexible polyester substrate. To facilitate clinical use, it is self-adhesive, incorporates a single connector and can perform dry or wet (with gel) recordings. The results show it to be a versatile electrode that can evaluate the optimal configuration for the identification of the intestinal slow wave and reject undesired interference. A bipolar concentric record with an outer ring diameter of 30 mm, a foam-free adhesive material, and electrolytic gel gave the best results.Grant from the Ministerio de Economia y Competitividad y del Fondo Europeo de Desarrollo Regional. DPI2015-68397-R (MINECO/FEDER).Zena-Giménez, VF.; Garcia Casado, FJ.; Ye Lin, Y.; Garcia-Breijo, E.; Prats-Boluda, G. (2018). A Flexible Multiring Concentric Electrode for Non-Invasive Identification of Intestinal Slow Waves. Sensors. 18(2):396-412. https://doi.org/10.3390/s18020396S39641218

Textile Concentric Ring Electrodes for ECG Recording Based on Screen-Printing Technology

[EN] Among many of the electrode designs used in electrocardiography (ECG), concentric ring electrodes (CREs) are one of the most promising due to their enhanced spatial resolution. Their development has undergone a great push due to their use in recent years; however, they are not yet widely used in clinical practice. CRE implementation in textiles will lead to a low cost, flexible, comfortable, and robust electrode capable of detecting high spatial resolution ECG signals. A textile CRE set has been designed and developed using screen-printing technology. This is a mature technology in the textile industry and, therefore, does not require heavy investments. Inks employed as conductive elements have been silver and a conducting polymer (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate; PEDOT: PSS). Conducting polymers have biocompatibility advantages, they can be used with flexible substrates, and they are available for several printing technologies. CREs implemented with both inks have been compared by analyzing their electric features and their performance in detecting ECG signals. The results reveal that silver CREs present a higher average thickness and slightly lower skin-electrode impedance than PEDOT: PSS CREs. As for ECG recordings with subjects at rest, both CREs allowed the uptake of bipolar concentric ECG signals (BC-ECG) with signal-to-noise ratios similar to that of conventional ECG recordings. Regarding the saturation and alterations of ECGs captured with textile CREs caused by intentional subject movements, silver CREs presented a more stable response (fewer saturations and alterations) than those of PEDOT: PSS. Moreover, BC-ECG signals provided higher spatial resolution compared to conventional ECG. This improved spatial resolution was manifested in the identification of P1 and P2 waves of atrial activity in most of the BC-ECG signals. It can be concluded that textile silver CREs are more suitable than those of PEDOT: PSS for obtaining BC-ECG records. These developed textile electrodes bring the use of CREs closer to the clinical environment.Grant from the Ministerio de Economia y Competitividad y del Fondo Europeo de Desarrollo Regional. DPI2015-68397-R (MINECO/FEDER). This work was also supported by the Spanish Government/FEDER funds (grant number MAT2015-64139-C4-3-R (MINECO/FEDER)).Lidon-Roger, JV.; Prats-Boluda, G.; Ye Lin, Y.; Garcia Casado, FJ.; Garcia-Breijo, E. (2018). Textile Concentric Ring Electrodes for ECG Recording Based on Screen-Printing Technology. Sensors. 18(1):300-314. https://doi.org/10.3390/s18010300S30031418

Enhancement of Non-Invasive Recording of Electroenterogram by Means of a Flexible Array of Concentric Ring Electrodes

Monitoring intestinal myoelectrical activity by electroenterogram (EEnG) would be of great clinical interest for diagnosing gastrointestinal pathologies and disorders. However, surface EEnG recordings are of very low amplitude and can be severely affected by baseline drifts and respiratory and electrocardiographic (ECG) interference. In this work, a flexible array of concentric ring electrodes was developed and tested to determine whether it can provide surface EEnG signals of better quality than bipolar recordings from conventional disc electrodes. With this aime, sixteen healthy subjects in a fasting state (>8h) underwent recording. The capabiltiy of detecting intestinal pacemaker activity (slow wave) and the influence of physiological interferences were studied. The signals obtained from the concentric ring electrodes proved to be more robust to ECG and respiratory interference than those from conventional disc electrodes. The results also show that intestinal EEnG components such as the slow wave can be more easily identified by the proposed system based on a flexible array of concentric ring electrodes. The developed active electrode array could be a very valuable tool for non-invasive diagnosis of disease states such as ischemia and motility disorders of the small bowel which are known to alter the normal enteric slow wave activity.Research supported in part by the Ministerio de Ciencia y Tecnologia de Espana (TEC 2010-16945). The proof-reading of this paper was funded by the Universitat Politecnica de Valencia, Spain.Garcia Casado, FJ.; Zena Giménez, VF.; Prats Boluda, G.; Ye Lin, Y. (2014). Enhancement of Non-Invasive Recording of Electroenterogram by Means of a Flexible Array of Concentric Ring Electrodes. Annals of Biomedical Engineering. 42(3):651-660. https://doi.org/10.1007/s10439-013-0935-yS651660423Abo, M., J. Liang, L. Qian, and J. D. Chen. 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Wikswo, Jr. Volume conductor effects on the spatial resolution of magnetic fields and electric potentials from gastrointestinal electrical activity. Med. Biol. Eng Comput. 39(1):35–43, 2001.Caenepeel, P., W. Janssens, A. Accarino, J. Janssens, G. Vantrappen, and H. Eyssen. Variation of slow-wave frequency and locking during the migrating myoelectric complex in dogs. Am. J. Physiol. 261(6):G1079–G1084, 1991.Chang, F. Y., C.-L. Lu, C.-Y. Chen, J.-C. Luo, S.-D. Lee, H.-C. Wu, and J. D. Z. Chen. Fasting and postprandial small intestinal slow waves non-invasively measured in subjects with total gastrectomy. Gastroenterology 22:247–252, 2006.Chen, J. D. Z. Non-invasive measurement of gastric myoelectrical activity and its analysis and applications. In: Annual International Conference of the IEEE Engineering in Medicine and Biology Society, Vol. 20, 1998, pp. 2802–2807.Chen, J. D. Z., D. Schirmer, and R. W. McCallum. 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Gastroenterology 85(6):1290–1300, 1983.Webster, J. G., J. W. Clark, Jr., M. R. Neuman, W. H. Olson, R. A. Peura, F. P. J. Primiano, M. P. Siedband, and L. A. Wheeler. Medical Instrumentation Application and Design. NewYork: Wiley, 1998.Weisbrodt, N. W. Motility of the small intestine. In: Physiology of the Gastrointestinal Tract, edited by L. R. Johnson. New York: Raven Press, 1987, pp. 631–663.Wu, D., H. C. Tsai, and B. He. On the estimation of the Laplacian electrocardiogram during ventricular activation. Ann. Biomed. Eng. 27(6):731–745, 1999.Ye-Lin, Y., J. Garcia-Casado, J. L. Martinez-de-Juan, G. Prats-Boluda, and J. L. Ponce. The detection of intestinal spike activity on surface electroenterograms. Phys. Med. Biol. 55(3):663–680, 2010.Ye-Lin, Y., J. Garcia-Casado, G. Prats-Boluda, J. L. Ponce, and J. L. Martinez-de-Juan. Enhancement of the non-invasive electroenterogram to identify intestinal pacemaker activity. Physiol. Meas. 30(9):885–902, 2009

Identification of atrial fibrillation drivers by means of concentric ring electrodes

The prevalence of atrial fibrillation (AF) has tripled in the last 50 years due to population aging. High-frequency (DFdriver) activated atrial regions lead the activation of the rest of the atria, disrupting the propagation wavefront. Fourier based spectral analysis of body surface potential maps have been proposed for DFdriver identification, although these approaches present serious drawbacks due to their limited spectral resolution for short AF epochs and the blurring effect of the volume conductor. Laplacian signals (BC-ECG) from bipolar concentric ring electrodes (CRE) have been shown to outperform the spatial resolution achieved with conventional unipolar recordings. Our aimed was to determine the best DFdriver estimator in endocardial electrograms and to assess the BC-ECG capacity of CRE to quantify AF activity non-invasively

Influence of voluntary contractions on the basal sEMG activity of the pelvic floor muscles

[EN] Chronic pelvic pain (CPP) is a complex clinical condition that affects many women, being sometimes misdiagnosed or mistreated,which can be treated with the infiltration of botulinum toxin (BoNTA). The pelvic floor musculature (PFM) condition from CPP patients can be assessed by means of surface electromyography (sEMG). The evaluation of the basal activity can help to detect a muscular dysfunction, therefore it is important to ensure that the PFM shows a minimum activation when its sEMG is being analysed. In this study, we recorded the sEMG of 25 women with CPP before and 8, 12 and 24 weeks after their treatment with BoNTA while they performed a protocol of 5 voluntary contractions. The root mean square (RMS) and sample entropy (SampEn) of basal segments pre- (B[PRE]), inter- (B[I]) and post- (B[POST]) contractions of the sEMG were computed and normalized according to the minimum (RMSnorm) and maximum (SampEnorm) of the recording. B(PRE) showed the lowest RMSnorm median both before and after the treatment with BoNTA, which proved that the activity of the PFM is minimum before the first contraction. As for SampEnnorm, although results were not so conclusive, they also indicated that B(PRE) should be taken as a reference to analyse the PFM function at its state of minimum activity. Future works aiming to characterize the effects of BoNTA in PFM by means of sEMG should consider basal segments before contractions to assess basal tone conditions.This study was funded by ISCIII, MCIU, VLC Campus in Convocatoria Ayudas: UPV-La Fe (INBIO): 2016 SPEHG (ID:C18), 2019 sEMG_BONTAv (ID:C06) and with funds from private contracts with Merz Pharma España S.L.Albaladejo-Belmonte, M.; Tarazona-Motes, M.; Nohales-Alfonso, FJ.; Alberola-Rubio, J.; Garcia-Casado, J. (2020). Influence of voluntary contractions on the basal sEMG activity of the pelvic floor muscles. Sociedad Española de Ingeniería Biomédica. 240-243. http://hdl.handle.net/10251/178256S24024

A comparative analysis of printing techniques by using an active concentric ring electrode for bioelectrical recording

Purpose This paper aims to present a comparison between three types of manufacturing techniques, namely, screen-printed, inkjet and gravure, using different types of inks, for the implementation of concentric ring electrodes which permit estimation of Laplacian potential on the body surface. Design/methodology/approach Flexible concentric ring electrodes not only present lower skin electrode contact impedance and lower baseline wander than rigid electrodes but are also less sensitive to interference and motion artefacts. The above three techniques allow printing of conductive inks on flexible substrates, and with this work, the authors aim to study which is the best technique and ink to obtain the best electrode response. Findings From the results obtained regarding ink thickness, resistivity, electrode resistance and other performance parameters derived from electrocardiographic signal recording tests, it can be said that concentric electrodes using the screen-printing and inkjet techniques are suitable for non-invasive bioelectric signal acquisition. Originality/value The development of new types of inks and substrates for the electronics industry and the adaptation of new manufacturing techniques allow for an improvement in the development of electrodes and sensors.This work was financially supported by the Spanish Government and European FEDER funds (MAT2012-38429-C04-04).García Breijo, E.; Prats Boluda, G.; Lidon-Roger, JV.; Ye Lin, Y.; Garcia Casado, FJ. (2015). A comparative analysis of printing techniques by using an active concentric ring electrode for bioelectrical recording. Microelectronics International. 32(2):103-107. https://doi.org/10.1108/MI-03-2015-0021S103107322Besio, W., Aakula, R., Koka, K., & Dai, W. (2006). Development of a Tri-polar Concentric Ring Electrode for Acquiring Accurate Laplacian Body Surface Potentials. Annals of Biomedical Engineering, 34(3), 426-435. doi:10.1007/s10439-005-9054-8Besio, W., & Chen, T. (2007). Tripolar Laplacian electrocardiogram and moment of activation isochronal mapping. Physiological Measurement, 28(5), 515-529. doi:10.1088/0967-3334/28/5/006He, B., & Cohen, R. J. (1992). Body surface Laplacian mapping of cardiac electrical activity. The American Journal of Cardiology, 70(20), 1617-1620. doi:10.1016/0002-9149(92)90471-aLu, C.C. and Tarjan, P.P. (2002), “An ultra-high common-mode rejection ratio (CMRR) AC instrumentation amplifier for laplacian electrocardiographic measurement”,Biomedical Instrumentation and Technology, Vol. 33 No. 1, pp. 76-83.Prats-Boluda, G. , Ye-Lin, Y. , Garcia-Breijo, E. , Ibanez, J. and Garcia-Casado, J. (2012), “Active flexible concentric ring electrode for non-invasive surface bioelectrical recordings”,Measurement Science & Technology, Vol. 23 No. 12

Identifying physical activity type in manual wheelchair users with spinal cord injury by means of accelerometers

Objectives: The main objective of this study was to develop and test classification algorithms based on machine learning using accelerometers to identify the activity type performed by manual wheelchair users with spinal cord injury (SCI). Setting: The study was conducted in the Physical Therapy department and the Physical Education and Sports department of the University of Valencia. Methods: A total of 20 volunteers were asked to perform 10 physical activities, lying down, body transfers, moving items, mopping, working on a computer, watching TV, arm-ergometer exercises, passive propulsion, slow propulsion and fast propulsion, while fitted with four accelerometers placed on both wrists, chest and waist. The activities were grouped into five categories: sedentary, locomotion, housework, body transfers and moderate physical activity. Different machine learning algorithms were used to develop individual and group activity classifiers from the acceleration data for different combinations of number and position of the accelerometers. Results: We found that although the accuracy of the classifiers for individual activities was moderate (55-72%), with higher values for a greater number of accelerometers, grouped activities were correctly classified in a high percentage of cases (83.2-93.6%). Conclusions: With only two accelerometers and the quadratic discriminant analysis algorithm we achieved a reasonably accurate group activity recognition system (490%). Such a system with the minimum of intervention would be a valuable tool for studying physical activity in individuals with SCI.X Garcia-Masso gratefully acknowledges the support of the University of Valencia under project UV-INV-PRECOMP13-115364.García-Massó, X.; Serra-Añó P.; Gonzalez, L.; Ye Lin, Y.; Prats-Boluda, G.; Garcia Casado, FJ. (2015). 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Textile Concentric Ring Electrodes: Influence of Position and Electrode Size on Cardiac Activity Monitoring

[EN] Continuous ECG monitoring can play an important role in the rapid detection of pathological signatures and arrhythmias. Current systems use electrodes with limitations in wearable long-term applications and spatial selectivity. In this work, two sizes of textile concentric ring electrodes (TCRE42 and TCRE50) were developed and tested for monitoring cardiac activity. The low-cost devices were found to be easy to implement and to potentially have the advantages of textile electrodes for being lightweight, stretchable, adjustable, washable, and long-lasting. Both TCREs yielded similar signal detectability of different ECG waves. The optimal P wave recording area (OPA) for detecting signals was on the upper right chest. Although the absolute signal amplitude of TCRE records was smaller than that of lead II, normalized amplitude in the OPA is similar for T wave and higher for P wave. The TCREs also allowed better analysis of P wave morphology and were able to detect more right and left atrial depolarization waves. TCRE48 showed slightly better detectability, normalized amplitude, and spatial selectivity than TCRE50 within the OPA. The authors consider the TCRE suitable for use in ubiquitous mobile health care systems, especially for atrial activity monitoring and diagnosisThis work was supported by grants from the Ministerio de Economia y Competitividad and the European Regional Development Fund (DPI2015-68397-R) (MINECO/FEDER). This work was also supported by the Spanish Government/FEDERfunds (MAT2015-64139-C4-3-R) (MINECO/FEDER).Prats-Boluda, G.; Ye Lin, Y.; Pradas-Novella, F.; Garcia-Breijo, E.; Garcia-Casado, J. (2018). Textile Concentric Ring Electrodes: Influence of Position and Electrode Size on Cardiac Activity Monitoring. Journal of Sensors. 2018. https://doi.org/10.1155/2018/7290867S201

Treatment of Dyspareunia with Botulinum Neurotoxin Type A: Clinical Improvement and Influence of Patients' Characteristics

[EN] The treatment of chronic pelvic pain (CPP) with botulinum neurotoxin type A (BoNT/A) has increased lately, but more studies assessing its effect are needed. This study aimed to evaluate the evolution of patients after BoNT/A infiltration and identify potential responders to treatment. Twenty-four women with CPP associated with dyspareunia were treated with 90 units of BoNT/A injected into their pelvic floor muscle (PFM). Clinical status and PFM activity were monitored in a previous visit (PV) and 12 and 24 weeks after the infiltration (W12, W24) by validated clinical questionnaires and surface electromyography (sEMG). The influence of patients' characteristics on the reduction in pain at W12 and W24 was also assessed. After treatment, pain scores and the impact of symptoms on quality of life dropped significantly, sexual function improved and sEMG signal amplitude decreased on both sides of the PFM with no adverse events. Headaches and bilateral pelvic pain were risk factors for a smaller pain improvement at W24, while lower back pain was a protective factor. Apart from reporting a significant clinical improvement of patients with CPP associated with dyspareunia after BoNT/A infiltration, this study shows that clinical characteristics should be analyzed in detail to identify potential responders to treatment.This study was funded by Universitat Politecnica de Valencia in Programa de Ayudas de Investigacion y Desarrollo (PAID-01-20), ISCIII, MCIU, VLC Campus in Convocatoria Ayudas: UPV-La Fe (INBIO): 2016 SPEHG (ID:C18), 2019 sEMG_BONTAv (ID:C06) and funds from private contracts with Merz Pharmaceuticals GmbH S.L.Tarazona-Motes, M.; Albaladejo-Belmonte, M.; Nohales-Alfonso, FJ.; De-Arriba, M.; Garcia-Casado, J.; Alberola-Rubio, J. (2021). Treatment of Dyspareunia with Botulinum Neurotoxin Type A: Clinical Improvement and Influence of Patients' Characteristics. International Journal of Environmental research and Public Health. 18(16):1-12. https://doi.org/10.3390/ijerph18168783S112181