Otto Dostál

A new approach to fully-reversible watermarking in medical imaging with breakthrough visibility parameters

Securing of medical images against intentional or accidental modification is a general issue in modern radiology. Watermarking, with its data-centric security, is very convenient for this purpose. We proposed a new method of fully reversible watermarking in medical imaging by combining the advantages of three traditional approaches—Reversible, Zero and RONI watermarking. The new method achieves exceptionally high values of Peak Signal to Noise Ratio and Structural Similarity index. The article evaluates the pros and cons of current methods of watermarking in medical imaging. Keeping the pros and eliminating the cons of the methods allows a new approach. Specific methods are selected and their application in practice described in detail. Application of the proposed method on a database of 6000 medical images from common hospital operations delivers very promising results which are discussed at the end of the article.

Integration of Telemedicine Activities in the Czech Republic

Institute of Computer Science of Masaryk University is working on the field of supporting medicine multimedia data transport archiving and processing more than ten years. Since first steps like transport of ultrasound and CT images across private fibre optics network these activities have grown up to regional PACS archive. Today more and more hospitals are participating on this project know under the name MediMed and we stand before scaling this project to republic wide application. Connection of remote hospitals introduced some not very common technical solutions. This paper describes current state of the art of MediMed project.

Medical traffic modeling for delay measurement in bottleneck network

The article deals with the delay of medical data in queues, caused by a bottleneck in the network. Primarily it focuses on the mathematical basis for defining the entrance traffic based on exponential distribution in the Network simulator and next it describes the possibility of calculating the delay from the trace file. Another alternative for the entrance traffic is also loading the input data from a file. In the simulation part a model of input medical imaging data is implemented, and simulations are performed on a network with a bottleneck, when the delay is measurement for different combinations of active input medical imaging sources.

MEDIMED - Regional Centre for Medicine Image Data Processing

Masaryk University in Brno is operating a regional PACS archive serving to mostly all hospitals in Brno metropolis and a lot of remote medicine institutions. The communication between modalities (i.e. CT, ultrasound, X-ray, etc.) PACS archive and viewing stations is based on DICOM standard. This paper describes current state of the art of this medicine images storage system.

PKI utilisation for PACS users authentication

Masaryk University in Brno is operating a regional PACS archive serving to mostly all hospitals in Brno metropolis and a lot of remote medicine institutions. For communication between modalities (i.e. CT, ultrasound, Xray, etc.) PACS archive and viewing stations is used DICOM standard. This standard was originally mentioned for usage inside one hospital so user authentication relays on IP address of viewing stations. This approach is not usable for communication between hospitals. In this paper we try to describe user authentication we are nowadays implementing in metropolitan PACS archive in Brno.

Wireless Technology in Medicine Applications

Institute of Computer Science of Masaryk University is working on the field of supporting medicine multimedia data transport archiving and processing more than ten years. Since first steps like transport of ultrasound and CT images across private fibre optics network these activities have grown up to regional PACS archive. Today more and more hospitals are participating on this project know under the name MediMed. For deployment of MediMed to some remote locations and especially to residence users (medicine specialists) it was necessary to utilise wireless and microwave technologies. Experiences with usage of wireless technology for delivery of medicine picture data are described in this paper.

Redundancy in Processing of Medical Image Data

The Regional PACS (Picture Archiving and Communication System) Project, MeDiMed (Metropolitan Digital Imaging in Medicine), an advanced system for the support of processing of medical image information, started as a collaborative effort among hospitals in the city of Brno to process medical multimedia data. Masaryk University is the coordinator of this project ensuring that the demands and requirements of radiology departments are met and overseeing the changing legislative standards and the practical possibilities of technology. Masaryk University, in cooperation with CESNET (the Czech National Research and Education Network Operator), also provides the necessary network infrastructure. The open system described in this paper was, from the start, designed to serve also as a reliable and accessible communication node and as an educational and research tool available to any hospital or another healthcare institution, including medical faculties, that participated in the system. The regional system is designed as a combination of distributed architecture in terms of incorporated hospital data centres and centralized architecture as the image studies are continuously being sent to the long-term broadly accessible archive in the centre.

Multimedia communication transmission in medicine

The authors deal with transmitting, archiving, and sharing medical data between various modalities. The emphasis is on PACS, transmission media ( in this case the Metropolitan Academic Computer Network in Brno, Czech Republic) and interconnection of various types of hospitals and medical institutions.

MEDIMED Shared Regional PACS Center - Case Study

Gradually, it changes the thinking of medical specialists and gets them to cooperate and share data about patients in electronic form. It builds a network of medical specialists. The impact of this project is not only in patient care but also in the education of medical specialists. Some data (e.g. typical cases of given disease) stored in the MeDiMed PACS archive can be anony‐ mized (i.e. personal data of patients is replaced by fictitious data) and used for educational purposes.

Service availability quantification in datacommunication networks

The aim of this work is to propose a novel methodology for quantification of datacommunication network availability. Currently used reliability calculation model is not very suitable for networking environment with many-to-many type of communication. In this paper we propose a novel method to quantify service availability in datacommunication networks. The proposed method reflects the multipoint-to-multipoint nature of datacommunication. The main idea of the proposed method is utilization of a special class of mathematical operations called t-norms.