N. van der Putten

Semi-automatic contour detection for volumetric quantification of intracoronary ultrasound

Volumetric quantification of the vessel lumen and plaque can be derived from a sequence of cross-sectional intracoronary ultrasound (ICUS) images. A semi-automatic approach has been developed to detect the contours of the lumen and plaque on a three-dimensional ICUS data set. This approach optimizes the contour detection algorithm by combining information from two perpendicular longitudinal views. Preliminary results have shown that this method is able to provide accurate and reproducible measurements of lumen and plaque volumes.<<ETX>>

An open source ECG toolkit with DICOM

Unlike the ubiquitous use of DICOM for sharing various medical image modalities, the storage and retrieval of digital 12-lead electrocardiograms across different ECG management systems is often limited to manual file-based export and import using vendor-specific solutions. In addition to SCP-ECG, a number of open standard initiatives have been introduced, such as DICOM-ECG and HL7 aECG. By extending and improving a previously developed ECG toolkit we have explored the capabilities of these open standards in terms of interoperability, filesize and transmission times. The ECG toolkit is almost entirely available under the Apache License Version 2.0.

A testbed project for DICOM images and waveforms integration

Today, in many catheterization labs, angiographic images are stored in DICOM format on CD, and reviewed from this DICOM CD. However, in clinical practice it would be very, advantageous to be able to store and display the images together with the waveforms (ECG, pressure) recorded simultaneously in the cathlab. To this end, a new supplement will be added to the DICOM standard (supplement 30). To gain experience with this DICOM-WV supplement, and to get comments from prospective users, we have initiated a project to create combined DICOM data-sets and to develop a viewer for times-synchronized display of images and waveforms, based on a draft version of the new DICOM-WV supplement. The initial results show that conversion of the waveform signals to DICOM-WV format can be easily performed and that time-synchronous display of images and waveforms opens new and exciting possibilities towards a fully integrated digital cathlab laboratory. Future plans include include a more generic solution to the time-synchronization problem, inclusion of other image modalities such as echo, inclusion of annotations and events and integration with DICOM supplement 23 (structured reporting).

A low cost PACS for angiography images

A low cost Picture Archiving and Communications System (PACS) for coronary Angiography images has been developed. The system allows direct on-line department and even hospital-wide availability of the angiographic image sequences. The system has been built with low cost PC-based components. It provides an interface to every standard PC-based DICOM image viewer. Osiris and a custom-built image viewer are currently in use. The first version of this system has been introduced and installed in the Thoraxcenters of Rotterdam and Groningen in the summer of 1997. An extension in progress is usage of this PACS as a base for the exchange of DICOM image data sets between local referring cardiac centers. Besides, this paper addresses the clinical usage and the functional and financial benefits of the system.

Glucose control as a model for implementation of a clinical decision support system

Glucose control in acute cardiac disease is difficult to achieve and may improve patient outcome. Because glucose levels were high at the Intensive Cardiac Care Unit, and adherence to a paper protocol was low, a web based decision support system for glucose control was developed. A board view of the currently admitted patients is provided; new glucose values are retrieved along with insulin infusion rates and patient data from the Patient Data Management System. For each new glucose value a pop-up is generated with the protocol advised action for insulin dosage and time for the next glucose measurement. Temporal trends in glucose and insulin values are displayed as an additional aid. An evaluation database is included in the design to provide feedback to the users on protocol compliance and glucose control. These data will also be used to improve the protocol.

Teleteaching and teleguiding using an intranetwork: A feasibility study

Telemedicine (more specific TeleCardiology), including teleteaching and teleguidance, is a rapidly growing area in cardiology. The availability of hand-held network ready ultrasound equipment is one of the accelerators for furthers developments. A pilot project for both teleteaching and -guiding was started in our institution. For teleteaching the requirements were not too strict, e.g. no real-time interaction with the remote site necessary and some loss in image quality was allowed. For teleguidance however, near real-time transmission of images with no loss in diagnostic quality was demanded For both teleprojects solutions were found and/or developed with complete satisfactory to the clinical demands.

Patient 98: a component-based multimedia workstation for cardiac care and research

A component-based medical workstation is under development. This workstation should provide to physicians, nurses and others access to all patient data including administrative data, summaries of studies, lab reports, signals and moving images. The main characteristics of this system are. 1. Integration of all patient information through one interface. The system comprises general medical information modules and dedicated cardiology and cardiac surgery modules. 2. Component-based. The framework of the system contains different patient selection modules in which individual components can be plugged in. Every component presents medical data of one patient (e.g.: a report or a sequence of images). The user can customize the workstation to every required circumstance.

A multicentre PDA project to support the clinical decision process

In the Netherlands, the departments of cardiology of all academic hospitals work together under the auspices of the Interuniversity Cardiology Institute of the Netherlands (ICIN). In many of these ICIN centers, PDAs are used to support the cardiologist in his daily practice. In these centers PDA versions are being developed of relevant clinical guidelines. Also, medical PDA applications are evaluated and distributed locally. To give a boost to these local efforts, representatives of 5 ICIN centers have started a PDA collaboration project, with the purpose to jointly develop or find PDA applications to support the clinical decision process. Relevant cardiology guidelines, such as the European (ESC) and national guidelines have been made available for the PDA. In addition, we have selected PDA applications that will be used in all centers, such as risk-prediction software, medical calculators and drug reference software. All PDA clinical guidelines and medical applications have been made available for download on a special Website.

A diagnostic component for the EPD-Car project

This paper describes a diagnostic module which is a part of the EPD-CAR (Electronic Patient Dossier for Cardiology) project of the Interuniversity Cardiology Institute of the Netherlands. It consists of 13 coding trees, each containing between 3 and 20 subitems. The scheme evolved from daily practice where standard coding schemes proved insufficient. It consists of one main diagnosis and up to 10 optional subdiagnoses. Back-end integration is achieved through conversion tables to ICD-9 and ICD-10. The current system is in use now,for over 1.5 years and contains diagnoses of over 11000 patients. The system is written in Visual Foxpro 6.0 and is an ActiveX-component.

General DICOM PACS server for echocardiography images

This study tackles a PC based general DICOM server for storage of studies acquired at all commercially available echocardiography workstations currently in use at the University Hospitals in the Netherlands. This storage can be done by media or network. For transfer via the network the DICOM storage communication protocol is chosen to import DICOM image objects. Via media, DICOM and other formats can be imported. A software module provides for automatic conversion to DICOM part 10 file format. The images are copied to the central repository and the ancillary data, encoded as DICOM tags, are stored to a relational database. References to the images are also table items of the same database. After query and retrieve via SQL, review with a generic DICOM viewer is possible on a routine basis at any PC in the hospital.