Petr Janků
Masaryk University
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Publication
Featured researches published by Petr Janků.
BMC Pregnancy and Childbirth | 2014
Vaclav Chudacek; Jiří Spilka; Miroslav Bursa; Petr Janků; Lukáš Hruban; Michal Huptych; Lenka Lhotska
BackgroundCardiotocography (CTG) is a monitoring of fetal heart rate and uterine contractions. Since 1960 it is routinely used by obstetricians to assess fetal well-being. Many attempts to introduce methods of automatic signal processing and evaluation have appeared during the last 20 years, however still no significant progress similar to that in the domain of adult heart rate variability, where open access databases are available (e.g. MIT-BIH), is visible. Based on a thorough review of the relevant publications, presented in this paper, the shortcomings of the current state are obvious. A lack of common ground for clinicians and technicians in the field hinders clinically usable progress. Our open access database of digital intrapartum cardiotocographic recordings aims to change that.DescriptionThe intrapartum CTG database consists in total of 552 intrapartum recordings, which were acquired between April 2010 and August 2012 at the obstetrics ward of the University Hospital in Brno, Czech Republic. All recordings were stored in electronic form in the OB TraceVue®;system. The recordings were selected from 9164 intrapartum recordings with clinical as well as technical considerations in mind. All recordings are at most 90 minutes long and start a maximum of 90 minutes before delivery. The time relation of CTG to delivery is known as well as the length of the second stage of labor which does not exceed 30 minutes. The majority of recordings (all but 46 cesarean sections) is – on purpose – from vaginal deliveries. All recordings have available biochemical markers as well as some more general clinical features. Full description of the database and reasoning behind selection of the parameters is presented in the paper.ConclusionA new open-access CTG database is introduced which should give the research community common ground for comparison of results on reasonably large database. We anticipate that after reading the paper, the reader will understand the context of the field from clinical and technical perspectives which will enable him/her to use the database and also understand its limitations.
Biomedical Signal Processing and Control | 2012
Jiří Spilka; Vaclav Chudacek; Michal Koucký; Lenka Lhotska; Michal Huptych; Petr Janků; Georgios Georgoulas; Chrysostomos D. Stylios
Highlights • We analyzed fetal heart rate of normal and acidemic fetuses. • We used conventional and nonlinear features for the signal analysis. • Addition of nonlinear features improves accuracy of classification. • The best nonlinear features are: Lempel Ziv complexity and Sample entropy. • Combination of conventional and nonlinear features provides the best accuracy. Abstract Fetal heart rate (FHR) is used to evaluate fetal well-being and enables clinicians to detect ongoing hypoxia during delivery. Routine clinical evaluation of intrapartum FHR is based on macroscopic morphological features visible to the naked eye. In this paper we evaluated conventional features and compared them to the nonlinear ones in the task of intrapartum FHR classification. The experiments were performed using a database of 217 FHR records with objective annotations, i.e. pH measurement. We have proven that the addition of nonlinear features improves accuracy of classification. The best classification results were achieved using a combination of conventional and nonlinear features with sensitivity of 73.4%, specificity of 76.3%, and F -measure of 71.9%. The best selected nonlinear features were: Lempel Ziv complexity, Sample entropy, and fractal dimension estimated by Higuchi method. Since the results of automatic signal evaluation are easily reproducible, the process of FHR evaluation can become more objective and may enable clinicians to focus on additional non-cardiotocography parameters influencing the fetus during delivery.
Physiological Measurement | 2011
Vaclav Chudacek; Jiří Spilka; Petr Janků; Michal Koucký; Lenka Lhotska; Michal Huptych
Cardiotocography is the monitoring of fetal heart rate (FHR) and uterine contractions (TOCO), used routinely since the 1960s by obstetricians to detect fetal hypoxia. The evaluation of the FHR in clinical settings is based on an evaluation of macroscopic morphological features and so far has managed to avoid adopting any achievements from the HRV research field. In this work, most of the features utilized for FHR characterization, including FIGO, HRV, nonlinear, wavelet, and time and frequency domain features, are investigated and assessed based on their statistical significance in the task of distinguishing the FHR into three FIGO classes. We assess the features on a large data set (552 records) and unlike in other published papers we use three-class expert evaluation of the records instead of the pH values. We conclude the paper by presenting the best uncorrelated features and their individual rank of importance according to the meta-analysis of three different ranking methods. The number of accelerations and decelerations, interval index, as well as Lempel-Ziv complexity and Higuchis fractal dimension are among the top five features.
International Journal of Gynecology & Obstetrics | 2001
O. Hrazdilová; Vít Unzeitig; Vladimír Znojil; Lydie IzakovičováHollá; Petr Janků; Anna Vasku
Objectives: Older maternal age is considered to be a risk factor for a number of pregnancy‐associated pathologies. Average weight increases with age. The aim of this study is to assess the effects of maternal age on selected disorders of pregnancy independently from the influence of maternal weight. Methods: The retrospective study included 910 women. The following parameters were evaluated: age, p‐BMI (body mass index before pregnancy), hypertension, severe hypertension, pre‐eclampsia, proteinuria, severe proteinuria, thromboembolic diseases, pregnancy duration and fetal growth restriction. Results: The correlation between the p‐BMI and age and BMI was confirmed (P<0.001). After filtering away the mutual influence of age and p‐BMI applying logistic regression we proved a statistically significant effect of p‐BMI on the incidence of hypertension, severe hypertension, proteinuria and pre‐eclampsia (P<0.001). The maternal age (cleared of the p‐BMI) effects only hypertension. Conclusions: Age alone proved to be a risk factor for severe hypertension or severe hypertension of the pregnant subjects. Increased risk for proteinuria, hypertension and pre‐eclampsia is directly associated with p‐BMI of the pregnant women, and only indirectly with their age.
international conference on information technology | 2013
Jiří Spilka; George Georgoulas; Petros S. Karvelis; Vangelis P. Oikonomou; Vaclav Chudacek; Chrysostomos D. Stylios; Lenka Lhotska; Petr Janků
Fetal heart rate (FHR) provides information about fetal well-being during labor. The FHR is usually the sole direct information channel from the fetus – undergoing the stress of labor – to the clinician who tries to detect possible ongoing hypoxia. For this paper, new CTU-UHB CTG database was used to compute more than 50 features. Features came from different domains ranging from classical morphological features based on FIGO guidelines to frequency-domain and non-linear features. Features were selected using the RELIEF (RELevance In Estimating Features) technique, and classified after applying Synthetic Minority Oversampling Technique (SMOTE) to the pathological class of the data. Nearest mean classifier with adaboost was used to obtain the final results. In results section besides the direct outcome of classification the top ten ranked features are presented.
European Journal of Anaesthesiology | 2016
Martina Kosinová; Petr Štourač; Hana Harazim; Petr Janků; Martin Huser; Stanislav Voháňka
Beckers Disease is an autosomal recessive type of myotonia congenita. Worldwide prevalence is about 1/100000. It is linked to mutations in CLCN1, the gene encoding skeletal muscle chloride channel. It reduces flow of chloride ions during repolarization and leads to sustained muscle contractions. Typical clinical symptoms are myotonic stiffness and “warm-up” phenomenon. 27 year old primipara with homozygote recessive mutation in CLCN1 (c.1437_1450del,p.480HfsX24) was indicated to elective caesarean section in 40 gestational week. In personal history she had thoracic stabilisation for scoliosis and hypothyreosis. We decided to provide the general anaesthesia with propofol in TCI mode (Schnider mode, C e =effective concentration 5 mcg/ml) and rocuronium 1 mg/kg IV for rapid sequence induction, monitoring the depth of neuromuscular blockade (NMB) on TOF WATCH SX device. The male newborn (APGAR score 9-10- 10) with no signs of pathology in acid-base balance in arterial umbilical blood was delivered. At the end of surgery (C e =1 mcg/ml, TOF=0, PTC=0) we administered sugammadex 4 mg/kg IV. It takes 2 min and 15 sec to reach TOF ratio 90% and subsequent extubation. After extubation she was breathing adequately, communicative, transferred to the recovery room and after two hours with no signs of residual NMB or respiratory problems back to the gynaecological ward to the monitored postoperative room. She was discharged home on 4 th day. This is the first report of anaesthetic management of a parturient with Beckers myotonia congenita who underwent CS under general anaesthesia. In this case we wanted to aware of using malignant hyperthermia (MH) triggering drugs, though the association with MH has been regarded as highly unlikely, suxamethonium which can cause total body rigidity and subsequent difficult airway management and neostigmine which can cause myotonic response.
Archive | 2013
Miroslav Bursa; Lenka Lhotska; Vaclav Chudacek; Jiri Spilka; Petr Janků; Martin Huser
Information mining from textual data becomes a very challenging task when the structure of the text record is very loose without any rules. The task becomes even more difficult when natural language is used and no apriori knowledge is available. The medical environment itself is also very specific: the natural language used in textual description varies with the personality creating the record (there are many personalized approaches), however it is restricted by terminology (i.e. medical terms, medical standards, etc.). Moreover, the typical patient record is filled with typographical errors, duplicates, ambiguities, syntax errors and many (nonstandard) abbreviations. This paper describes the process of mining information from loosely structured medical textual records with no apriori knowledge. In the paper we depict the process of mining a large dataset of 50,000–120,000 records 20 attributes in database tables, originating from the hospital information system (thanks go to the University Hospital in Brno, Czech Republic) recording over 11 years. This paper concerns only textual attributes with free text input, that means 620,000 text fields in 16 attributes. Each attribute item contains ~800–1,500 characters (diagnoses, medications, etc.). The output of this task is a set of ordered/nominal attributes suitable for rule discovery mining and automated processing that can help in asphyxia prediction during delivery. The proposed technique has an important impact on reduction of the processing time of loosely structured textual records for experts. Note that this project is an ongoing process (and research) and new data are irregularly received from the medical facility, justifying the need for robust and fool-proof algorithms
Archive | 2019
Michal Huptych; Vaclav Chudacek; Ibrahim Abou Khashabh; Jiří Spilka; Miroslav Bursa; Lukáš Hruban; Petr Janků
The Electronic Delivery Book (EDB), an electronic information system, was developed in cooperation with obstetricians, midwives, and neonatologists from the University Hospital in Brno. The main aim was to create structured electronic documentation of selected delivery-related parameters based on the existing paper-based documentation. The system contains information from the different stages of delivery: parameters of the pregnancy, medications/interventions during the birth, outcome measures for the newborn(s), and primary attributes from neonatology. The EDB also allows creating overviews and basic statistics for everyday clinical needs and offers structured data for retrospective as well as prospective studies. One of the first results based on data collected using the EDB was the analysis aimed at identification of potential risk factors for low umbilical cord artery pH in term, singleton pregnancies. The data selected from EDB represents a basis for the retrospective case-control study. Cases were deliveries characterized by umbilical cord artery pH ≤7.05, controls were with no sign of hypoxia. In the database of 10637 deliveries, collected between 2014 and 2015 at the University Hospital in Brno, we identified 99 cases. Univariate analysis of clinical features was performed. The following risk factors were associated with low pH: the length of the first stage (odds ratio (OR) 1.40; 95% CI 1.04–1.89) and the length of the second stage of labor (OR 2.86; 1.70–4.81), primipara (OR 2.99; 1.90–4.71) and meconium stained fluid (OR 1.60; 1.07–2.38).
Frontiers in Physiology | 2018
Radek Martinek; Radana Kahankova; Janusz Jezewski; Rene Jaros; Jitka Mohylová; Marcel Fajkus; Jan Nedoma; Petr Janků; Homer Nazeran
Non-adaptive signal processing methods have been successfully applied to extract fetal electrocardiograms (fECGs) from maternal abdominal electrocardiograms (aECGs); and initial tests to evaluate the efficacy of these methods have been carried out by using synthetic data. Nevertheless, performance evaluation of such methods using real data is a much more challenging task and has neither been fully undertaken nor reported in the literature. Therefore, in this investigation, we aimed to compare the effectiveness of two popular non-adaptive methods (the ICA and PCA) to explore the non-invasive (NI) extraction (separation) of fECGs, also known as NI-fECGs from aECGs. The performance of these well-known methods was enhanced by an adaptive algorithm, compensating amplitude difference and time shift between the estimated components. We used real signals compiled in 12 recordings (real01–real12). Five of the recordings were from the publicly available database (PhysioNet-Abdominal and Direct Fetal Electrocardiogram Database), which included data recorded by multiple abdominal electrodes. Seven more recordings were acquired by measurements performed at the Institute of Medical Technology and Equipment, Zabrze, Poland. Therefore, in total we used 60 min of data (i.e., around 88,000 R waves) for our experiments. This dataset covers different gestational ages, fetal positions, fetal positions, maternal body mass indices (BMI), etc. Such a unique heterogeneous dataset of sufficient length combining continuous Fetal Scalp Electrode (FSE) acquired and abdominal ECG recordings allows for robust testing of the applied ICA and PCA methods. The performance of these signal separation methods was then comprehensively evaluated by comparing the fetal Heart Rate (fHR) values determined from the extracted fECGs with those calculated from the fECG signals recorded directly by means of a reference FSE. Additionally, we tested the possibility of non-invasive ST analysis (NI-STAN) by determining the T/QRS ratio. Our results demonstrated that even though these advanced signal processing methods are suitable for the non-invasive estimation and monitoring of the fHR information from maternal aECG signals, their utility for further morphological analysis of the extracted fECG signals remains questionable and warrants further work.
Brain and behavior | 2018
Hana Harazim; Pavel Štourač; Petr Janků; Hana Zelinková; Kamil Frank; Michal Dufek; Petr Štourač
Multiple sclerosis (MS) often occurs in young women and the effect of obstetric anesthesia/analgesia on the disease is poorly understood. No previous study has investigated the course of the disease in women in labor in the Czech Republic. The aim of this study was to evaluate the occurrence or absence of relapses in the 6‐month postpartum period in MS parturients with and without obstetric anesthesia/analgesia.