Diseño y desarrollo de un sistema para el registro y monitorización de la actividad mioeléctrica uterina

El nacimiento prematuro está entre los mayores problemas de salud en el mundo. Las técnicas usadas actualmente para la monitorización del parto son poco fiables y subjetivas.El objetivo de este proyecto es el desarrollo de un sistema que permita el registro de la actividad electrica uterina junto con las señales de uso clínco habitual.Alberola Rubio, J. (2010). Diseño y desarrollo de un sistema para el registro y monitorización de la actividad mioeléctrica uterina. http://hdl.handle.net/10251/14211Archivo delegad

Estudio electrofisiológico del útero humano durante el embarazo a partir de registros no invasivos del electrohisterograma

Título: “Estudio electrofisiológico del útero humano durante el embarazo a partir de registros no invasivos del electrohisterograma” La actividad uterina se monitoriza durante el embarazo y el parto con el objetivo de obtener información sobre las contracciones uterinas, para ayudar a la estimación del inicio y el progreso del trabajo de parto y para evaluar el estado de salud del conjunto materno-fetal. Actualmente, las tocografía externa e interna, son las técnicas más extendidas para la monitorización de la actividad uterina. Éstas técnicas manométricas de uso clínico habitual se limitan a monitorizar las contracciones uterinas a partir de resultante mecánica de la actividad bioeléctrica contráctil. Además, la tocografía externa aporta información poco fiable y dependiente de la subjetividad del examinador. Recientemente, el análisis de la actividad mioeléctrica uterina captada en superficie (electrohisterograma, EHG) ha demostrado ser uno de los marcadores biofísicos más prometedores no sólo de la dinámica uterina sino también del estado electrofisiológico del útero. Sin embargo, a pesar de haberse demostrando que el EHG aporta información muy valiosa, no ha habido una traslación de esta técnica al uso clínico. Introducir el EHG en la práctica clínica requiere atender las principales demandas de los obstetras, como son: simplificar los protocolos y sistemas de adquisición de señal, facilitar la interpretación de la información adquirida y verificar su utilidad en escenarios clínicos. Por ello, en esta Tesis Doctoral se ha comparado la capacidad de detección de la actividad contráctil uterina de los sistemas utilizados en la práctica clínica habitual, respecto de diferentes configuraciones de registros de EHG en superficie abdominal y con el objetivo de acercar lo máximo posible la electrohisterografía a la clínica, se ha desarrollado electrodos más cómodos y de mejor contacto, un monitor obstétrico de EHG amigable en entorno clínico, se ha estudiado la generación de señales fácilmente interpretables por el personal clínico, se han implementado sistemas automáticos de detección de artefactos para así evitar la confusión en la interpretación de las mismas y sistemas de diagnóstico automáticos para la predicción de parto en menos de 24h

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

Comparison of non-invasive electrohysterographic recording techniques for monitoring uterine dynamics

Non-invasive recording of uterine myoelectric activity (electrohysterogram, EHG) could provide an alternative to monitoring uterine dynamics by systems based on tocodynamometer (TOCO). Laplacian recording of bioelectric signals has been shown to give better spatial resolution and less interference than mono and bipolar surface recordings. The aim of this work was to study the signal quality obtaines from monopolar, bipolar and Laplacian techniques in EHG recordings, as well as to assess their ability to detect uterine contractions. Twenty-two recording sessions were carried out on singleton pregnant women during the active phase of labour. In each session the following simultaneous recordings were obtained: internal uterine pressure (IUP), external tension of abdominal wall (TOCO) and EHG signals (5 monopolar and 4 bipolar recordings, 1 discrete aproximation to the Laplacian of the potential and 2 estimates of the Laplacian from two active annular electrodes). The results obtained show that EHG is able to detect a higher number of uterine contractions than TOCO. Laplacian recordings give improved signal quality over monopolar and bipolar techniques, reduce maternal cardiac interference and improve the signal-to-noise ratio. The optimal position for recording EHG was found to be the uterine median axis and the lower centre-right umbilical zone.Research partly supported by the Spanish Ministerio de Ciencia y Tecnologia (TEC2010-16945) and the Universitat Politecnica de Valencia (PAID 2009/10-2298). The translation of this paper was funded by the Universitat Politecnica de Valencia, Spain.Alberola Rubio, J.; Prats Boluda, G.; Ye Lin, Y.; Valero, J.; Perales Marin, AJ.; Garcia Casado, FJ. (2013). Comparison of non-invasive electrohysterographic recording techniques for monitoring uterine dynamics. Medical Engineering and Physics. 35(12):1736-1743. https://doi.org/10.1016/j.medengphy.2013.07.008S17361743351

Uterine contractile efficiency indexes for labor prediction: a bivariate approach from multichannel electrohysterographic records

[EN] Labor prediction is one of the most challenging goals in obstetrics, mainly due to the poor understanding of the factors responsible for the onset of labor. The electrohysterogram (EHG) is the recording of the myoelectrical activity of myometrial cells and has been shown to provide relevant information on the electrophysiological state of the uterus. This information could be used to obtain more accurate labor predictions than those of the currently used techniques, such as the Bishop score, tocography or biochemical markers. Indeed, a number of efforts have already been made to predict labor by this method, separately characterizing the intensity, the coupling degree of the EHG signals and myometrial cell excitability, these being the cornerstones on which contraction efficiency is built. Although EHG characterization can distinguish between different obstetric situations, the reported results have not been shown to provide a practical tool for the clinical detection of true labor. The aim of this work was thus to define and calculate indexes from multichannel EHG recordings related to all the phenomena involved in the efficiency of uterine myoelectrical activity (intensity, excitability and synchronization) and to combine them to form global efficiency indexes (GEI) able to predict delivery in less than 7/14 days. Four EHG synchronization indexes were assessed: linear correlation, the imaginary part of the coherence, phase synchronization and permutation cross mutual information. The results show that even though the synchronization and excitability efficiency indexes can detect increasing trends as labor approaches, they cannot predict labor in less than 7/14 days. However, intensity seems to be the main factor that contributes to myometrial efficiency and is able to predict labor in less than 7/14 days. All the GEls present increasing monotonic trends as pregnancy advances and are able to identify (p < 0.05) patients who will deliver in less than 7/14 days better than single channel and single phenomenon parameters. The GEI based on the permutation cross mutual information shows especially promising results. A simplified EHG recording protocol is proposed here for clinical practice, capable of predicting deliveries in less than 7/14 days, consisting of 4 electrodes vertically aligned with the median line of the uterus. (C) 2018 Elsevier Ltd. All rights reserved.The authors are grateful to Zhenhu Liang, of the Yanshan University, who provided essential information for computing the PLV and NPCMI synchronization indexes. This work was supported by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund (DPI2015-68397-R, MINECO/FEDER).Mas-Cabo, J.; Ye Lin, Y.; Garcia-Casado, J.; Alberola Rubio, J.; Perales Marín, AJ.; Prats-Boluda, G. (2018). Uterine contractile efficiency indexes for labor prediction: a bivariate approach from multichannel electrohysterographic records. Biomedical Signal Processing and Control. 46:238-248. https://doi.org/10.1016/j.bspc.2018.07.018S2382484

Progression of Doppler changes in early-onset small for gestational age fetuses. How frequent are the different progression sequences?

OBJECTIVE: To evaluate the progression of Doppler abnormalities in early-onset fetal smallness (SGA). METHODS: A total of 948 Doppler examinations of the umbilical artery (UA), middle cerebral artery (MCA) and ductus venosus (DV), belonging to 405 early-onset SGA fetuses, were studied, evaluating the sequences of Doppler progression, the interval examination-labor at which Doppler became abnormal and the cumulative sum of Doppler anomalies in relation with labor proximity. RESULTS: The most frequent sequences were that in which only the UA pulsatility index (PI) became abnormal (42.1%) and that in which an abnormal UA PI appeared first, followed by an abnormal MCA PI (24.2%). In general, 71.3% of the fetuses followed the classical progression sequence UA→MCA→DV, mostly in the early stages of growth restriction (84.1%). In addition, the UA PI was the first parameter to be affected (9 weeks before delivery), followed by the MCA PI and the DV PIV (1 and 0 weeks). Finally, the UA PI began to sum anomalies 5 weeks before delivery, while the MCA and DV did it at 3 and 1 weeks before the pregnancy ended. CONCLUSIONS: In early-onset SGA fetuses, Doppler progression tends to follow a predictable order, with sequential changes in the umbilical, cerebral and DV impedances

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

Electrohysterography in the diagnosis of preterm birth: a review

This is an author-created, un-copyedited versíon of an article published in Physiological Measurement. IOP Publishing Ltd is not responsíble for any errors or omissíons in this versíon of the manuscript or any versíon derived from it. The Versíon of Record is available online at http://doi.org/10.1088/1361-6579/aaad56.[EN] Preterm birth (PTB) is one of the most common and serious complications in pregnancy. About 15 million preterm neonates are born every year, with ratios of 10-15% of total births. In industrialized countries, preterm delivery is responsible for 70% of mortality and 75% of morbidity in the neonatal period. Diagnostic means for its timely risk assessment are lacking and the underlying physiological mechanisms are unclear. Surface recording of the uterine myoelectrical activity (electrohysterogram, EHG) has emerged as a better uterine dynamics monitoring technique than traditional surface pressure recordings and provides information on the condition of uterine muscle in different obstetrical scenarios with emphasis on predicting preterm deliveries. Objective: A comprehensive review of the literature was performed on studies related to the use of the electrohysterogram in the PTB context. Approach: This review presents and discusses the results according to the different types of parameter (temporal and spectral, non-linear and bivariate) used for EHG characterization. Main results: Electrohysterogram analysis reveals that the uterine electrophysiological changes that precede spontaneous preterm labor are associated with contractions of more intensity, higher frequency content, faster and more organized propagated activity and stronger coupling of different uterine areas. Temporal, spectral, non-linear and bivariate EHG analyses therefore provide useful and complementary information. Classificatory techniques of different types and varying complexity have been developed to diagnose PTB. The information derived from these different types of EHG parameters, either individually or in combination, is able to provide more accurate predictions of PTB than current clinical methods. However, in order to extend EHG to clinical applications, the recording set-up should be simplified, be less intrusive and more robust-and signal analysis should be automated without requiring much supervision and yield physiologically interpretable results. Significance: This review provides a general background to PTB and describes how EHG can be used to better understand its underlying physiological mechanisms and improve its prediction. The findings will help future research workers to decide the most appropriate EHG features to be used in their analyses and facilitate future clinical EHG applications in order to improve PTB prediction.This work was supported by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund under grant DPI2015-68397-R.Garcia-Casado, J.; Ye Lin, Y.; Prats-Boluda, G.; Mas-Cabo, J.; Alberola Rubio, J.; Perales Marin, AJ. (2018). Electrohysterography in the diagnosis of preterm birth: a review. Physiological Measurement. 39(2). https://doi.org/10.1088/1361-6579/aaad56S39

Characterization of Pelvic Floor Activity in Healthy Subjects and with Chronic Pelvic Pain: Diagnostic Potential of Surface Electromyography

[EN] Chronic pelvic pain (CPP) is a highly disabling disorder in women usually associated with hypertonic dysfunction of the pelvic floor musculature (PFM). The literature on the subject is not conclusive about the diagnostic potential of surface electromyography (sEMG), which could be due to poor signal characterization. In this study, we characterized the PFM activity of three groups of 24 subjects each: CPP patients with deep dyspareunia associated with a myofascial syndrome (CPP group), healthy women over 35 and/or parous (>35/P group, i.e., CPP counterparts) and under 35 and nulliparous (RMS), a predominance of low-frequency components (DI), greater complexity (>SampEn) and lower synchronization on the same side (35/P group. The same trend in differences was found between healthy women (35/P) associated with aging and parity. These results show that sEMG can reveal alterations in PFM electrophysiology and provide clinicians with objective information for CPP diagnosis.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.Albaladejo-Belmonte, M.; Tarazona-Motes, M.; Nohales-Alfonso, FJ.; De-Arriba, M.; Alberola-Rubio, J.; Garcia-Casado, J. (2021). Characterization of Pelvic Floor Activity in Healthy Subjects and with Chronic Pelvic Pain: Diagnostic Potential of Surface Electromyography. Sensors. 21(6):1-17. https://doi.org/10.3390/s21062225S11721

Design and Assessment of a Robust and Generalizable ANN-Based Classifier for the Prediction of Premature Birth by means of Multichannel Electrohysterographic Records

[EN] Preterm labor is one of the major causes of neonatal deaths and also the cause of significant health and development impairments in those who survive. However, there are still no reliable and accurate tools for preterm labor prediction in clinical settings. Electrohysterography (EHG) has been proven to provide relevant information on the labor time horizon. Many studies focused on predicting preterm labor by using temporal, spectral, and nonlinear parameters extracted from single EHG recordings. However, multichannel analysis, which includes information from the whole uterus and about coupling between the recording areas, may provide better results. The cross validation method is often used to design classifiers and evaluate their performance. However, when the validation dataset is used to tune the classifier hyperparameters, the performance metrics of this dataset may not properly assess its generalization capacity. In this work, we developed and compared different classifiers, based on artificial neural networks, for predicting preterm labor using EHG features from single and multichannel recordings. A set of temporal, spectral, nonlinear, and synchronization parameters computed from EHG recordings was used as the input features. All the classifiers were evaluated on independent test datasets, which were never ¿seen¿ by the models, to determine their generalization capacity. Classifiers¿ performance was also evaluated when obstetrical data were included. The experimental results show that the classifier performance metrics were significantly lower in the test dataset (AUC range 76-91%) than in the train and validation sets (AUC range 90-99%). The multichannel classifiers outperformed the single-channel classifiers, especially when information was combined into mean efficiency indexes and included coupling information between channels. Including obstetrical data slightly improved the classifier metrics and reached an AUC of for the test dataset. These results show promise for the transfer of the EHG technique to preterm labor prediction in clinical practice.This work was supported by the Spanish Ministry of Economy and Competitiveness, the European Regional Development Fund (DPI2015-68397-R, MINECO/FEDER, and RTI2018-094449-A-I00-AR); Generalitat Valenciana (AICO/2019/220); and the VLC/Campus (UPV-FE-2018-B03).Mas-Cabo, J.; Prats-Boluda, G.; Garcia-Casado, J.; Alberola Rubio, J.; Perales Marín, AJ.; Ye Lin, Y. (2019). Design and Assessment of a Robust and Generalizable ANN-Based Classifier for the Prediction of Premature Birth by means of Multichannel Electrohysterographic Records. Journal of Sensors. 2019:1-13. https://doi.org/10.1155/2019/5373810S1132019Goldenberg, R. L., Culhane, J. F., Iams, J. D., & Romero, R. (2008). Epidemiology and causes of preterm birth. 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