Andy Marsh

EEG analysis in a telemedical virtual world

Telemedicine creates virtual medical collaborative environments. We propose here a novel concept of virtual medical devices (VMD) for telemedical applications. VMDs provide different views on biomedical recordings and efficient signal analysis. In this paper we present a telemedical EEG analysis environment based on virtual reality technologies. The same EEG signal/recording could be viewed either as a waveform or as animated topographic maps on a 3D head model. In addition to visualization, sonification is used as a secondary presentation modality. The environment is based on a VRML head model animated with Java applets, and allows the use of standard web browser.

Modeling tumor growth and irradiation response in vitro-a combination of high-performance computing and Web-based technologies including VRML visualization

A simplified three-dimensional Monte Carlo simulation model of in vitro tumor growth and response to fractionated radiotherapeutic schemes is presented in this paper. The paper aims at both the optimization of radiotherapy and the provision of insight into the biological mechanisms involved in tumor development. The basics of the modeling philosophy of Duechting (1968, 1981, 1992, 1995) have been adopted and substantially extended. The main processes taken into account by the model are the transitions between the cell cycle phases, the diffusion of oxygen and glucose, and the cell survival probabilities following irradiation. Specific algorithms satisfactorily describing tumor expansion and shrinkage have been applied, whereas a novel approach to the modeling of the tumor response to irradiation has been proposed and implemented. High-performance computing systems in conjunction with Web technologies have coped with the particularly high computer memory and processing demands. A visualization system based on the MATLAB software package and the virtual-reality modeling language has been employed. Its utilization has led to a spectacular representation of both the external surface and the internal structure of the developing tumor. The simulation model has been applied to the special case of small cell lung carcinoma in vitro irradiated according to both the standard and accelerated fractionation schemes. A good qualitative agreement with laboratory experience has been observed in all cases. Accordingly, the hypothesis that advanced simulation models for the in silico testing of tumor irradiation schemes could substantially enhance the radiotherapy optimization process is further strengthened. Currently, our group is investigating extensions of the presented algorithms so that efficient descriptions of the corresponding clinical (in vivo) cases are achieved.

MR functional cardiac imaging: segmentation, measurement and WWW based visualisation of 4D data

Abstract This paper considers the problem of ventricular segmentation and visualisation from dynamic (4D) MR cardiac data covering an entire patient cardiac cycle, in a format that is compatible with the web. Four different methods are evaluated for the process of segmentation of the objects of interest: The K-means clustering algorithm, the fuzzy K-means (FKM) algorithm, self-organizing maps (SOMs) and seeded region growing algorithm. The technique of active surface is then subsequently applied to refine the segmentation results, employing a deformable generalised cylinder as geometric primitive. The final ventricular models are presented in VRML 2.0 format. The same process is repeated for all the 3D volumes of the cardiac cycle. The radial displacement between end systole and end diastole is calculated for each point of the active surface and is encoded in colour on the VRML vertex, using the RGB colour model. Using the VRML 2.0 specifications, morphing is performed showing all cardiac phases in real time. The expert has the ability to view the objects and interact with them using a simple internet browser. Preliminary results of normal and abnormal cases indicate that very important pathological situations (such as infarction) can be visualised and thus easily diagnosed and localised with the assistance of the proposed technique.

EUROMED - Combining WWW and HPCN to Support Advanced Medical Imaging

Throughout Europe there currently exists numerous High Performance Computing sites housing a variety of computing platforms encorporating the spectrum of vendors and topologies. The potential for their interconnection with high speed data links is a realistic possibility and essential for the future of HPCN and any vision of “information highways” or “information societies” that are now being imaged. One major beneficiary of this interaction could be the health community. The concept of telemedicine captures much of what is developing in terms of technology implementation, especially if it is combined with the growth of the Internet and World Wide Web (WWW). Telemedicine provides the potential to reduce European geographical disparity to communicate medical practices. However, to include the latest research developments and new advanced imaging techniques requires the use of a variety of High Performance Computing platforms. The EUROMED project provides this link via a “meta-centre” combining of four European sites.

Solution of electrically large planar scattering problems using parallel computed method of moments technique

Parallel computations of an integral equation technique in conjunction with a Method of Moments (MoM) is introduced, in examining electromagnetic illumination of electrically large scatterers. To this end, the electromagnetic scattering of an incident wave illuminating an electrically large conducting rectangular plate of infinitesimal thickness is analyzed. An integral equation is derived in terms of the conductivity currents induced on the plate surface, which is solved by employing entire domain Galerkin technique, with Chebyshev type basis functions. The resulting algorithm parallelization enables extension of the proposed methodology above the resonance region. Numerical results are computed for several scatterer sizes and excitation source types, with significant near-linear speedups.

VR in medicine: Virtual colonoscopy

Colon/rectal cancer is the second most common cause of death, yet among the most preventable when detected in its early stages. The traditional diagnostic procedures cause tremendous discomfort and are deeply invasive. The motivation for this work is firstly to develop an alternative technique to visualise the inner mucosal surface of the colonic wall. This technique will be based on three-dimensional (3D) visualisation and virtual reality to perform virtual endoscopy. However, there is a requirement of vast computational support. Therefore, secondly, this paper will discuss the possibilities adopting high performance computing and networking to support virtual reality medical applications.

Benchmarking high‐performance computing platforms in analyzing electrically large planar conducting structures via a parallel computed method of moments technique

The analysis of electrically large planar conducting structures is examined by employing parallel computations of an integral equation technique in conjunction with a method of moments. The integral equation, in terms of the induced conductivity currents, is solved using an entire domain Galerkin technique, with Chebyshev-type basis fonctions. The resulting algorithm parallelization enables extension of the proposed methodology above the resonance region. Numerical results are computed for several scatterer sizes and excitations source types on varying high-performance computing platforms: Silicon Graphics Power Challenge, Intel Paragon XP/S, CRAY C-90, and CRAY T3D. A comparison is made among these diverse computing platforms for their applicability-suitability in solving electromagnetic problems in the domain of electrically large planar scattering structures. Their suitability is not only judged on performance obtained but also on ease of code portation.

EUROMED-JAVA: Trusted Third Party Services for Securing Medical Java Applets

EUROMED, a DG III project1, aims to create the foundation of telemedical information society. EUROMED-ETS, an INFOSEC project, provided secure communications among EUROMED participants by establishing Trusted Third Party Services (TTPs) over the Web. Java technology plays an important role in EUROMED. In this paper, the threats that Java technology introduces to EUROMED are explored and security countermeasures are proposed, utilizing the TTP infrastructure.

Coupling HPCN and Virtual Reality in a Telemedical Information Society

This paper presents the on-going work concerning the definition of a standardised use of Virtual Reality in a telemedical information society. It presents the collaboration of the EUROMED project and the usage of the VRASP over the WWW to perform Virtual Assisted Surgery. The aim of the EUROMED project is to standardise the use of the WWW for advanced medical image diagnosis in a telemedical information society. Its interconnection with the state-of-the-art virtual assisted surgery package VRASP, developed at the BIR laboratory Mayo Clinic will allow for a standardised approach to be defined on the adoption of HPC to support Virtual Reality in a telemedically aware information society.

The E-CARE Project - Removing the Wires

The European Commission IST project called E-CARE: Medical Expert Syxtem for Continuity of Care and Healthy Lifestyle presents innovative health services that win introduce new practices in health monitoring and decision support on health matters as well as healthy living. E-CARE will cater for a wide range of scenarios, from patients on short-term (1-2 months) recovery from treatment to patients with long-torrn illness, elderly people and people predisposed to diseases, which live a normal life but at the same time need constant attention on the state of their health. One aspect of E-Care that is the major issue for the introduction of 3G Medical services in general is the systematic removal of the connecting wires which link the patients vital data sensors to the medical server which is monitoring the patient. This paper presents the steps adopted within the E-Care project and therefore a blueprint for developing further 3G Medical services.