Papers by Kyriakos Kassis
Proceedings of 18th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1997
In this paper a finite elements analysis tool is presented that has been developed in order to ac... more In this paper a finite elements analysis tool is presented that has been developed in order to achieve a full simulation of the Red Blood Cell (RBC) motion and deformation in the circulation. Hence this tool is used to test the theoretically proposed constitutive relations that describe the mechanoelastic properties of the RBC. Consequently, it opens the way for finding the optimum constitutive relations that best fits the actual, observed in vivo RBC properties and its deformed RBC shapes. Here, the first results are shown, namely the RBC shape deformation during motion in free running plasma, for a specific set of constitutive equations concerning both the membrane and the cytoplasm too
Medical Applications of Lasers III, 1996
ABSTRACT Export Date: 24 July 2012, Source: Scopus
2009 9th International Conference on Information Technology and Applications in Biomedicine, 2009
Public healthcare is a basic service provided by governments to citizens which is increasingly co... more Public healthcare is a basic service provided by governments to citizens which is increasingly coming under pressure as the European population ages and the ratio of working to elderly persons falls. A way to make public spending on healthcare more efficient is to ensure that the money is spent on legitimate causes. This paper presents the work of the iWebCare project where a flexible, on-line, fraud detection, web services platform was designed and developed. It aims to help those in the Healthcare business, minimize the loss of funds to fraud. The Platform is able to detect erroneous or suspicious records in submitted health care data sets, ensuring homogeneity and consistency and promoting awareness and harmonization of fraud detection practices across health care systems in the EU. Critical objectives included, the development of an ontology of health care data associated with semantic rules, implementation and initial population of an ontology and rules repository, development of a fraud detection engine and implementation of a data mining module. The potential impact of this work can be substantial. More money on healthcare mean better healthcare. Living conditions and the trust of citizens in public healthcare will be improved.
Public healthcare is a basic service provided by governments to citizens which is increasingly co... more Public healthcare is a basic service provided by governments to citizens which is increasingly coming under pressure as the European population ages and the ratio of working to elderly persons falls. A way to make public spending on healthcare more efficient is to ensure that the money is spent on legitimate causes. This paper presents the work of the iWebCare project where a flexible, on-line, fraud detection, web services platform was designed and developed. It aims to help those in the Healthcare business, minimize the loss of funds to fraud. The Platform is able to detect erroneous or suspicious records in submitted health care data sets, ensuring homogeneity and consistency and promoting awareness and harmonization of fraud detection practices across health care systems in the EU. Critical objectives included, the development of an ontology of health care data associated with semantic rules, implementation and initial population of an ontology and rules repository, development of a fraud detection engine and implementation of a data mining module. The potential impact of this work can be substantial. More money on healthcare mean better healthcare. Living conditions and the trust of citizens in public healthcare will be improved.
General & diagnostic pathology
The aim of this study was to estimate the percentage of the carotid atherosclerotic plaque compon... more The aim of this study was to estimate the percentage of the carotid atherosclerotic plaque components using image analysis in 50 cases of carotid endarterectomies as well as the search for a probable correlation with the neurologic status of the patients. According to their preoperational neurologic status, the patients were classified as asymptomatic (Group I), symptomatic-TIA (Group II) and symptomatic-previous stroke (Group III). For the image analysis and the exact estimation of the carotid plaque components, special algorithms were developed. The following plaque components were measured: fibrous component, calcium, cellular infiltrations, cholesterol and hemorrhage. Between the groups I-III, there was not found any statistically significant difference of the mean value of all the estimated parameters. Our results indicate that the morphology of the carotid atheromatous plaque seems not to be correlated with the neurologic status of the patients.
Proceedings of SPIE - The International Society for Optical Engineering
ABSTRACT Export Date: 24 July 2012, Source: Scopus
Technology and health care: official journal of the European Society for Engineering and Medicine
Interoperability plays a great role in the statistical data life cycle and basically allows busin... more Interoperability plays a great role in the statistical data life cycle and basically allows businesses and citizens to have easier access to more timely statistical data with well-defined semantics between the figures. In a modern data exchange scenario business experts, organisations at EU and international level (such as Member States, UN, OECD, IMF, ECB etc.) and citizens may equally act either as data providers or as data consumers of statistical information. Their need is to automatically extract statistical figures, which are described using the same metadata which accompany the data during the process of collection and transmission. In such a visionary scenario, aggregate data providers, such as government agencies, statistical authorities and institutes, disseminate their data through publicly accessible web services that can be queried in an ad hoc manner to provide just the requested data at the requested aggregation granularity. The availability of new data is published i...
Biomedical Sensing, Imaging, and Tracking Technologies I, 1996
ABSTRACT The aim of our study is to investigate if myocardial fibrosis measured by image analysis... more ABSTRACT The aim of our study is to investigate if myocardial fibrosis measured by image analysis may be considered as an important and accurate index of dilated cardiomyopathy and its prognosis. The study group consisted of 24 patients with dilated cardiomyopathy which was diagnosed by echocardiography, radionuclide ventriculography, cardiac catheterization and left ventricular endomyocardial biopsy. The patients' overall disability was conventionally expressed with the criteria for functional capacity. Using image analysis the percentage of fibrosis in a total of 35 myocardial biopsies was measured accurately. A comparison study between the percentage of myocardial fibrosis and the clinical parameters (left ventricular ejection fraction and overall functional capacity) showing the degree of each patient's heart failure followed. A correlation was found among fibrosis, left ventricular ejection fraction and overall functional capacity. The cases with small values of fibrosis (less than 10%) have big values of ejection fraction and belong in Class I of overall functional capacity. The cases with big values of fibrosis (greater than 10%) belong in Classes III and IV of overall functional capacity and have small values of ejection fraction. The results of the comparison study were presented graphically and were considered significant. Myocardial fibrosis measured by image analysis might be considered an important prognostic index of dilated cardiomyopathy.
Medical Applications of Lasers III, 1996
ABSTRACT Export Date: 24 July 2012, Source: Scopus
Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems VI, 1996
ABSTRACT A field where fluorescence spectroscopy might be of great interest for diagnosis, is cor... more ABSTRACT A field where fluorescence spectroscopy might be of great interest for diagnosis, is coronary atherosclerosis and therefore spectroscopic characterization of cardiovascular tissues has been extensively studied. Nevertheless there are several limitations in the precise interpretation of the spectroscopic differences, between normal and atherosclerotic arteries since the tissue is a complex and multilayer structure. Therefore the spectra of individual chromophores could overlap and re-absorption phenomena could occur, too. Another major difficulty arises from the necessity of convenient classification algorithms and the assessment of their feasibility to use fluorescence information, for accurate diagnosis. As a result in order to assess the feasibility of utilizing spectral information to discriminate arterial tissue type several classification algorithms were developed and evaluated. In this work the following pattern recognition techniques have been tested and evaluated: (1) Distance measure (or norm, or metric) based pattern recognition techniques. Methodologically speaking, based on the histopathological diagnosis, a training set of spectra has been classified into four different categories (healthy, fibrous, calcified, heavy calcified) and in each of these four training groups a representative spectrum has been recorded. (2) A pattern recognition method based on statistical considerations. Discrimination between either the four aforementioned classes (categories) or pairs of them is achieved since peak intensities in appropriate wavelengths appear to correlate efficiently with tissue type. The difference of each training set member from the corresponding representative has been defined by using various appropriate distance measures and the sample statistical properties for each category of the training group has been found. Appropriate statistical analysis has been performed in order to deduce the distribution of the distance measures and of the coefficients of the whole population for each one of the four categories, with at least 99% confidence interval. A validation set of samples has been used in order to test and compare the aforementioned pattern recognition algorithms. A performance comparison of the aforementioned algorithms has been undertaken.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Le Journal de Physique IV, 1994
ABSTRACT Laser angioplasty is a promising new technology, which sometimes offers the surgeon an a... more ABSTRACT Laser angioplasty is a promising new technology, which sometimes offers the surgeon an alternative tool to conventional therapy. One of the main prerequisites of using powerful pulsed lasers in angioplasty is the optimum choice of the irradiation parameters (the wavelength, the pulse shape and duration, the energy parameters). Infrared lasers have numerous applications in surgery. Among them the pulsed CO2 laser emitting at 10.6 microns and the pulsed Nd:YAG laser emitting at 1.064 microns are the most widely used, since the delivery of laser energy in short pulses of high peak pulse power limits distant thermal effects. The CO2 laser wavelength is greatly absorbed by tissue water, while the Nd:YAG laser wavelength is poorly absorbed by water or other tissue chromophores, affecting deeper the tissue. The CO2 laser incises effectively the tissue, but presents inadequate coagulation, while the Nd:YAG laser seems to present better coagulation properties. In this work, a comparative study of pulsed Nd:YAG and CO2 lasers in ablating cardiovascular tissue, is presented. The irradiation regime of the two lasers is determined, for the specific tissue and/or pathology. Also the depth of thermally induced coagulation is measured. The results are presented according to the efficacy of each laser for incision and/or coagulation.
Pulsed laser ablation of atheromatous arteries was studied at three wavelengths in the near ultra... more Pulsed laser ablation of atheromatous arteries was studied at three wavelengths in the near ultraviolet, visible, and near infrared regions of the spectrum. The experiments were done with an Nd:YAG laser, 9 nsec pulse duration. The wavelength could be fixed at 1064 nm, 532 nm, or 355 nm through KDP crystals. Laser fluences ranged up to 80 J/cm2 and repetition
Proceedings of 18th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 1997
In this paper a finite elements analysis tool is presented that has been developed in order to ac... more In this paper a finite elements analysis tool is presented that has been developed in order to achieve a full simulation of the Red Blood Cell (RBC) motion and deformation in the circulation. Hence this tool is used to test the theoretically proposed constitutive relations that describe the mechanoelastic properties of the RBC. Consequently, it opens the way for finding the optimum constitutive relations that best fits the actual, observed in vivo RBC properties and its deformed RBC shapes. Here, the first results are shown, namely the RBC shape deformation during motion in free running plasma, for a specific set of constitutive equations concerning both the membrane and the cytoplasm too
Biorheology, 1995
We previously described the use of a counter-rotating cone and plate Rheoscope to measure the tim... more We previously described the use of a counter-rotating cone and plate Rheoscope to measure the time and force dependence of shear-induced breakup of doublets of sphered, swollen and frxed red cells (SSRC) cross-linked by
2009 9th International Conference on Information Technology and Applications in Biomedicine, 2009
Public healthcare is a basic service provided by governments to citizens which is increasingly co... more Public healthcare is a basic service provided by governments to citizens which is increasingly coming under pressure as the European population ages and the ratio of working to elderly persons falls. A way to make public spending on healthcare more efficient is to ensure that the money is spent on legitimate causes. This paper presents the work of the iWebCare project where a flexible, on-line, fraud detection, web services platform was designed and developed. It aims to help those in the Healthcare business, minimize the loss of funds to fraud. The Platform is able to detect erroneous or suspicious records in submitted health care data sets, ensuring homogeneity and consistency and promoting awareness and harmonization of fraud detection practices across health care systems in the EU. Critical objectives included, the development of an ontology of health care data associated with semantic rules, implementation and initial population of an ontology and rules repository, development of a fraud detection engine and implementation of a data mining module. The potential impact of this work can be substantial. More money on healthcare mean better healthcare. Living conditions and the trust of citizens in public healthcare will be improved.
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Papers by Kyriakos Kassis