Papers by Efthyvoulos Kyriacou
Studies in Health Technology and Informatics, 2000
Cardiovascular disease (CVD) can be identified through ultrasound scans of the arteries and more ... more Cardiovascular disease (CVD) can be identified through ultrasound scans of the arteries and more specific the common carotid artery (CCA). Measurement of the intima–media thickness (IMT) of the CCA is an established indicator of CVD. Several reports have indicated differences in the IMT of CCA and related then with various risk factors as well as their association with the risk of stroke. Along this direction; this chapter presents methods for the stratification of CVD based on manual and automated IMT measurements for both the left and right common carotid arteries. The results are based on a group of 1104 longitudinal ultrasound images acquired from 568 men and 536 women out of which 125 had cardiovascular symptoms (CVD). The main findings can be summarized as follows: (1) there was no significant difference between the CCA left side IMT and the right side IMT; (2) there were statistical significant differences for the IMT measurements between the normal group and the CVD group fo...
Introduction: The support of prehospital and emergency call handling and the impact of Covid-19 i... more Introduction: The support of prehospital and emergency call handling and the impact of Covid-19 is discussed throughout this study. The initial purpose was to create an electronic system (eEmergency system) in order to support, improve, and help the procedure of handling emergency calls. This system was expanded to facilitate needed operation changes for Covid-19. Materials and Methods: An effort to reform the procedures followed for emergency call handling and Ambulance dispatch started on the Island of Cyprus in 2016; along that direction, a central call centre was created. The electronic system presented in this work was designed for this call centre and the new organization of the ambulance services. The main features are the support for ambulance fleet handling, the support for emergency call evaluation and triage procedure, and the improvement of communication between the call centre and the ambulance vehicles. This system started regular operation at the end of 2018. One year...
2017 IEEE 30th International Symposium on Computer-Based Medical Systems (CBMS)
During a human brain MRI acquisition the resulting image is formed out of 2D slices. The slices m... more During a human brain MRI acquisition the resulting image is formed out of 2D slices. The slices must then be aligned and reconstructed to provide a 3-dimensional (3D) visualization of the brain volume. We propose in this work, an integrated system for the register ion and 3D reconstruction of DICOM MRI images and lesions of the brain acquired from multiple sclerosis (MS) subjects at two different time intervals (time 0 (T0) and time 1 (T1)). The system facilitates the follow up of the MS disease development and will aid the doctor to accurately manage the follow up of the disease. It involves a 6-stage analysis (preprocessing, lesion segmentation, registration, 3D reconstruction, volume estimation and method evaluation), as well as module quantitative evaluation of the method. The system was evaluated based on one MRI phantom and one DICOM MRI image of the brain. The accuracy of the proposed registration and reconstruction (- / -) method was 78.5%/97.2% and 95.4%/95.8% for the phantom and the MRI images respectively. These preliminary results provide evidence that the proposed system could be applied in future in the clinical practice.
Telehealth and Mobile Health, 2015
IEEE-EMBS International Conference on Biomedical and Health Informatics (BHI), 2014
The intima-media thickness (IMT) of the common carotid artery (CCA) is a well-known indicator of ... more The intima-media thickness (IMT) of the common carotid artery (CCA) is a well-known indicator of cardiovascular disease (CVD). The objective of this study was to investigate the application of texture analysis of the medial layer (ML) of the CCA, and how texture features vary between the left and right carotid sides, as well as how these are affected by CVD. The study was performed on 200 longitudinal-section ultrasound images from 150 normal subjects, and 50 symptomatic subjects suffering with CVD. The ML was segmented automatically by a snakes segmentation system and 61 different texture features were extracted. This study showed that only the gray level difference statistics (GLDS) correlation measure of the ML component could be used to differentiate between normal subjects, and subjects suffering with CVD for either the left or the right CCA sides. We furthermore found that a number of texture features were significantly different between the left and the right CCA sides. We have found no other studies in the literature where these findings could be compared to. These findings should be further validated on a larger number of subjects as well as combined with additional risk factors.
Biomedical Signal Processing and Control, 2011
2020 IEEE 20th Mediterranean Electrotechnical Conference ( MELECON), 2020
The main purpose of this study was to create an electronic system (eEmergency system) in order to... more The main purpose of this study was to create an electronic system (eEmergency system) in order to support, improve and help the procedure of handling emergency calls. An effort to reform the procedures followed for emergency call handling and Ambulance dispatch started on the Island of Cyprus since 2016; along that direction, a central call center was created. The present electronic system was designed for this call center. The main features are the support for ambulance fleet handling, the support for emergency call evaluation and triage procedure and the improvement of communication between the call center and the ambulance vehicles. The main components and the design of this system are outlined in this paper. The part of incident evaluation and ambulance handling, has been in daily practice for more than one year and since then more than 62000 calls were successfully handled and recorded with the use of this system. This system was successfully used from the beginning of the pand...
IEEE journal of translational engineering in health and medicine, 2017
The objective of this paper was to investigate texture feature variability in ultrasound video of... more The objective of this paper was to investigate texture feature variability in ultrasound video of the carotid artery during the cardiac cycle in an attempt to define new discriminatory biomarkers of the vulnerable plaque. More specifically, in this paper, 120 longitudinal ultrasound videos, acquired from 40 normal (N) subjects from the common carotid artery and 40 asymptomatic (A) and 40 symptomatic (S) subjects from the proximal internal carotid artery were investigated. The videos were intensity normalized and despeckled, and the intima-media complex (IMC) (from the N subjects) and the atherosclerotic carotid plaques (from the A and S subjects) were segmented from each video, in order to extract the M-mode image, and the texture features associated with cardiac states of systole and diastole. The main results of this paper can be summarized as follows: 1) texture features varied significantly throughout the cardiac cycle with significant differences identified between the cardiac ...
Healthcare Technology Letters, 2016
Τhe performance of rescuers and personnel handling major emergencies or crisis events can be sign... more Τhe performance of rescuers and personnel handling major emergencies or crisis events can be significantly improved through continuous training and through technology support. The work done in order to create a system has been discussed which can support both resources and victims during a crisis or major emergency event. More specifically, the system supports real-time management of firefighter teams, rescue teams, health services, and victims during a major disaster. It can be deployed in an ad hoc manner in the disaster area, as a stand-alone infrastructure (using its own telecommunications and power). It mainly consists of a control station, which is installed in the area command centre, the firefighters units, the rescuers units, the ambulance vehicles units, and the telemedicine units that can be used in order to support victim handling at the casualties clearing station. The system has been tested and improved through continuous communication with experts and through professional exercises; the results and conclusions are presented.
Journal of Vascular Surgery, 2016
Background: Carotid plaque echodensity and texture features predict cerebrovascular symptomatolog... more Background: Carotid plaque echodensity and texture features predict cerebrovascular symptomatology. Our purpose was to determine the association of echodensity and textural features obtained from a digital image analysis (DIA) program with histologic features of plaque instability as well as to identify the specific morphologic characteristics of unstable plaques. Methods: Patients scheduled to undergo carotid endarterectomy were recruited and underwent carotid ultrasound imaging. DIA was performed to extract echodensity and textural features using Plaque Texture Analysis software (LifeQ Medical Ltd, Nicosia, Cyprus). Carotid plaque surgical specimens were obtained and analyzed histologically. Principal component analysis (PCA) was performed to reduce imaging variables. Logistic regression models were used to determine if PCA variables and individual imaging variables predicted histologic features of plaque instability. Results: Image analysis data from 160 patients were analyzed. Individual imaging features of plaque echolucency and homogeneity were associated with a more unstable plaque phenotype on histology. These results were independent of age, sex, and degree of carotid stenosis. PCA reduced 39 individual imaging variables to five PCA variables. PCA1 and PCA2 were significantly associated with overall plaque instability on histology (both P [ .02), whereas PCA3 did not achieve statistical significance (P [ .07). Conclusions: DIA features of carotid plaques are associated with histologic plaque instability as assessed by multiple histologic features. Importantly, unstable plaques on histology appear more echolucent and homogeneous on ultrasound imaging. These results are independent of stenosis, suggesting that image analysis may have a role in refining the selection of patients who undergo carotid endarterectomy.
Proceedings of the 10th IEEE International Conference on Information Technology and Applications in Biomedicine, 2010
Abstract The purpose of this paper is to explore the use of texture features analysis for evaluat... more Abstract The purpose of this paper is to explore the use of texture features analysis for evaluating normal appearing white matter (NAWM) areas in brain Magnetic Resonance Imaging (MRI) scans of patients with a first demyelinating event (Clinically Isolated Syndrome-CIS) that have been subsequently converted (in follow up MRI scans) in demyelinating plaques. Texture features analysis was carried out in NAWM areas selected from transverse sections of T2-weighted MRI scans acquired from 10 untreated subjects ...
2010 4th International Symposium on Communications, Control and Signal Processing (ISCCSP), 2010
Monitoring the wall and plaque changes in the carotid artery (CA) can provide useful information ... more Monitoring the wall and plaque changes in the carotid artery (CA) can provide useful information for the assessment of the atherosclerotic disease. Using a motion mode (M-mode) image, detailed information may be obtained about wall and lumen dimensions, systolic and diastolic artery diameter and distension, wall and plaque motion and thickness, and also their corresponding states (timings). The wall thickness and the diameter of the CA change during the cardiac cycle are an indicator of regional contraction and therefore an indication of a disease. The objective of this work was to investigate how M-mode state based modeling of the CA can be derived from a B-mode ultrasound video. Briefly, 10 longitudinal CA ultrasound videos acquired from symptomatic subjects at risk of atherosclerosis were broken into frames and their M-mode images were generated. These were then despeckled and the atherosclerotic carotid plaque was segmented from each video, in order to extract the states of the video. By identifying the states of the CA, we can distinguish between normal and abnormal plaque motion. It was shown in this work, that M-mode state based modeling derived from Bmode videos can be used successfully to derive the carotid states and assess the corresponding wall changes. However, further work in a larger number of videos is needed for validating the proposed method and to differentiate between normal and abnormal state based plaque motion analysis.
2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2015
IEEE Transactions on Information Technology in Biomedicine
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Papers by Efthyvoulos Kyriacou