[A patient with a life-threatening disulfiram-ethanol reaction]. / Een patiënt met een levensbedreigende disulfiram-ethanolreactie.

BACKGROUND: Disulfiram is a substance often used to treat alcohol dependency. The agent may be effective when used as supportive therapy. Disulfiram causes an accumulation of acetaldehyde when alcohol is consumed, which results in unpleasant sensations such as warmth, nausea, vomiting and headache. CASE DESCRIPTION: A patient was brought into the emergency ward with a suspected alcohol intoxication. As it turned out, she had experienced a severe disulfiram-ethanol reaction which had led to hypotensive shock; extensive abnormalities were seen on the ECG. The patient was admitted to the intensive care unit. High-dose norepinephrine treatment was needed to bring the blood pressure back to normal. The use of disulfiram was only discovered at a later stage. CONCLUSION: In rare cases, a disulfiram-ethanol reaction can lead to life-threatening situations. Descriptions of toxicity at acetaldehyde levels of 5 mg/l are found in the literature. In this article, we describe a life-threatening reaction which developed at a level between only 2.3-3.0 mg/l. This case shows that the provision of information on a patient's use of medications and adequate communication are just as important as toxicological screening in the laboratory.

[Immunophenotyping of haematologic malignancies]. / Immuunfenotypering van hematologische maligniteiten.

Over the last 10 years, immunophenotyping of haematologic malignancies has become an indispensable diagnostic supplement to the classical morphological approach. Immunophenotyping of haematopoietic cells is performed with the use of a number of monoclonal antibodies (MOABs), which are directed specifically against structures of blood cells that become expressed at the different stages of differentiation and maturation. Cells to which the fluorescently labelled MOABs are directed can be recognised and measured using fluorescence microscopy or fluorescence flow cytometry. Many MOABs, fluorochromes and user-friendly flow cytometers have become available in the last 15 years, as a result of which immunophenotyping is now routinely applied in clinical practice. Immunophenotyping has the potential to classify leukaemias and other malignant lymphomas according to cell type and stage of maturation. This information is important for the establishment of the right diagnosis and prognosis, and for the optimal treatment choice. In a number of cases immunophenotyping provides information which cannot be obtained by simple morphological investigation. The immunophenotyping of blood and bone-marrow cells is also a sensitive method for detecting minimal residual disease after an apparent complete remission has been achieved.

MANUS--a wheelchair-mounted rehabilitation robot.

Rehabilitation robots are assistive devices designed for use by people with severe disability in order to gain independence in tasks of daily living. MANUS is a wheelchair-mounted general-purpose manipulator now in use with over 100 people in their homes in the Netherlands, in France and in other countries. MANUS has six main degrees of freedom, excluding the gripper. To keep the arm slim, the motors are placed in the main base. The resulting low mass of the arm ensures a reduced impulse in case of collision. A complex system of toothed belts, hollow shafts and geared wheels drives the end-effector. MANUS is equipped with a two-fingered gripper. The fingers have passive canting mechanisms which ensure a three-point grasping action for most objects. A modular control system is used for steering the manipulator to its desired position. For this, a simple but effective user interface has been developed which is configurable by the end-user as well as by the therapist.

Interactive realtime Doppler-ultrasound visualization of the heart.

Heart valve insufficiencies can optimally be assessed using transesophageal, triggered, three-dimensional ultrasound imaging. The dynamic ultrasound data contain morphological as well as functional components which are recorded and displayed simultaneously. It allows the visualization of intracardiac motion which is an important parameter to detect abnormal flow caused by defect valves. A realtime reconstruction is desired to get a spatial impression on the one hand and to interactively clip parts of the volume on the other hand. Therefore, we use the OpenGL Volumizer API. Scalability of the visualization was tested with respect to different workstations and graphics resources using a Multipipe Utility library. The combination of both APIs enables a visualization of volumetric and functional data with frame rates up to 10 frames per second. By using the proposed method, it is possible to visualize the jet in the original color-coding which is employed during a conventional two-dimensional examination for displaying the velocity values. The morphological and the functional data are handled as two independent data channels. A good scalability from low cost up to high end graphic workstations is given by the use of the MPU. The quality of the resulting 3D images allows exact differentiation of heart valve insufficiencies to support the diagnostic procedure.

Design of a distributed CORBA based image processing server.

This paper presents the design and implementation of a distributed image processing server based on CORBA. Existing image processing tools were encapsulated in a common way with this server. Data exchange and conversion is done automatically inside the server, hiding these tasks from the user. The different image processing tools are visible as one large collection of algorithms and due to the use of CORBA are accessible via intra-/internet.

HIV-infected patient with a Rhodococcus equi pneumonia.

The case history of a HIV patient with a pulmonary infect of Rhodococcus equi is presented. He recovered after prolonged treatment with antibiotics and lobectomy. The Rhodococcus equi infection was the presenting symptom of his impaired immune status caused by HIV infection.

Extending a teleradiology system by tools for visualization and volumetric analysis through a plug-in mechanism.

This paper describes ongoing research concerning interactive volume visualization coupled with tools for volumetric analysis. To establish an easy to use application, the three-dimensional-visualization has been embedded in a state of the art teleradiology system, where additional functionality is often desired beyond basic image transfer and management. Major clinical requirements for deriving spatial measures are covered by the tools, in order to realize extended diagnosis support and therapy planning. Introducing a general plug-in mechanism, this work exemplarily describes the useful extension of an approved application. Interactive visualization was achieved by a hybrid approach taking advantage of both the precise volume visualization based on the Heidelberg ray-tracing model and the graphics acceleration capabilities of modern workstations. Several tools for volumetric analysis extend the three-dimensional-viewing. They are controlled by adequate input devices to select locations in the data volume, measure anatomical structures or initiate a segmentation process. Moreover, a haptic interface can be connected to provide a more realistic feedback while navigating within the three-dimensional-reconstruction. The work is closely related to research in the field of heart, liver and head surgery. In cooperation with our medical partners the development of tools as presented facilitates the integration of image analysis into the clinical routine.

Virtual surgery in a (tele-)radiology framework.

This paper presents telemedicine as an extension of a teleradiology framework through tools for virtual surgery. To classify the described methods and applications, the research field of virtual reality (VR) is broadly reviewed. Differences with respect to technical equipment, methodological requirements and areas of application are pointed out. Desktop VR, augmented reality, and virtual reality are differentiated and discussed in some typical contexts of diagnostic support, surgical planning, therapeutic procedures, simulation and training. Visualization techniques are compared as a prerequisite for virtual reality and assigned to distinct levels of immersion. The advantage of a hybrid visualization kernel is emphasized with respect to the desktop VR applications that are subsequently shown. Moreover, software design aspects are considered by outlining functional openness in the architecture of the host system. Here, a teleradiology workstation was extended by dedicated tools for surgical planning through a plug-in mechanism. Examples of recent areas of application are introduced such as liver tumor resection planning, diagnostic support in heart surgery, and craniofacial surgery planning. In the future, surgical planning systems will become more important. They will benefit from improvements in image acquisition and communication, new image processing approaches, and techniques for data presentation. This will facilitate preoperative planning and intraoperative applications.

Borderless teleradiology with CHILI.

Teleradiology is one of the most evolved areas of telemedicine, but one of the basic problems which remains unsolved concerns system compatibility. The DICOM (Digital Imaging and Communications in Medicine) standard is a prerequisite, but it is not sufficient in all aspects. Examples of other currently open issues are security and cooperative work in synchronous teleconferences. Users without a DICOM radiological workstation would benefit from the ability to join a teleradiology network without any special tools. Drawbacks of many teleradiology systems are that they are monolithic in their software design and cannot be adapted to the actual user's environment. Existing radiological systems currently cannot be extended with additional software components. Consequently, every new application usually needs a new workstation with a different look and feel, which must be connected and integrated into the existing infrastructure. This paper introduces the second generation teleradiology system CHILI. The system has been designed to match both the teleradiology requirements of the American College of Radiology (ACR), and the functionality and usability needs of the users. The experiences of software developers and teleradiology users who participated in the first years of the clinical use of CHILI's predecessor MEDICUS have been integrated into a new design. The system has been designed as a component-based architecture. The most powerful communication protocol for data exchange and teleconferencing is the CHILI protocol, which includes a strong data security concept. The system offers, in addition to its own secure protocol, several different communication Methods: DICOM, classic e-mail, Remote Copy functions (RCP), File Transfer Protocol (FTP), the internet protocols HTTP (HyperText Transfer Protocol) and HTTPS (HyperText Transfer Protocol Secure),and CD-ROMs for off-line communication. These transfer METHODS allow the user to send images to nearly anyone with a computer and a network. The drawbacks of the non-CHILI protocols are that teleconferences are not possible, and that the user must take reasonable precautions for data privacy and security. The CHILI PlugIn mechanism enables the users or third parties to extend the system capabilities by adding powerful image postprocessing functions or interfaces to other information systems. Suitable PlugIns can be either existing programs, or dedicated applications programmed with interfaces to the CHILI components. The developer may freely choose programming languages and interface toolkits. The CHILI architecture is a powerful and flexible environment for Picture Archiving and Communications Systems (PACS)and teleradiology. More than 40 systems are currently running in clinical routine in Germany. More than 300,000 images have been distributed among the communication partners in the last two years. Feedback and suggestions from the users influenced the system architecture by a great extent. The proposed and implemented system has been optimized to be as platform independent, open, and secure as possible.

[Integration of functional and morphologic MRI data for preoperative 3D visualization of tumors. Example: cervical carcinoma]. / Integration von funktionellen und morphologischen MR-Daten zur präoperativen 3D-Visualisierung von Tumoren. Beispiel Zervixkarzinom.

PURPOSE: The goal of this exemplary study was to integrate morphological and functional MRI to establish computer-based, pre-operative therapy planning for tumors, instancing cervical carcinoma. METHODS: For morphological representation T1-weighted, filtered 3D sequences were investigated within a hierarchical segmentation approach. Using a method for image registration, segmented structures were combined and overlaid with functional information of contrast medium-enhanced, dynamic MRI. After assigning colour attributes to the segmented structures, they were presented using a method for direct volume visualisation. RESULTS: Segmentation of organs and vessels as well as tissue differentiation yielded a morphological visualisation of anatomical structures that were overlaid with pharmacokinetic parameters derived from dynamic MRI, subsequently. Thereby, three-dimensional, arbitrary views on the functional data were displayed. CONCLUSIONS: Image analysis and visualisation of the acquired MR data establishes both a morphologic and functional evaluation of suspect lesions and adjacent organs. By integrating morphologic and functional MRI additional information can be gathered that possibly impinge on preoperative planning.

Extending a teleradiology system by tools for 3D-visualization and volumetric analysis through a plug-in mechanism.

This paper describes ongoing research concerning interactive volume visualization coupled with tools for volumetric analysis. To establish an easy to use application, the 3D-visualization has been embedded in a state of the art teleradiology system, where additional functionality is often desired beyond basic image transfer and management. Major clinical requirements for deriving spatial measures are covered by the tools, in order to realize extended diagnosis support and therapy planning. Introducing the general plug-in mechanism this work exemplarily describes the useful extension of an approved application. Interactive visualization was achieved by a hybrid approach taking advantage of both the precise volume visualization based on the Heidelberg Raytracing Model and the graphics acceleration of modern workstations. Several tools for volumetric analysis extend the 3D-viewing. They offer 3D-pointing devices to select locations in the data volume, measure anatomical structures or control segmentation processes. A haptic interface provides a realistic perception while navigating within the 3D-reconstruction. The work is closely related to research work in the field of heart, liver and head surgery. In cooperation with our medical partners the development of tools as presented proceed the integration of image analysis into clinical routine.

[Chylothorax as a complication of sarcoidosis]. / Chylothorax als Komplikation einer Sarkoidose.

This case report features a male patient of 45 years of age presenting with a right sided moderately compressive pleural effusion, that was clearly identified as chylothorax on thoracocentesis. Sarcoidosis with systemic involvement had already been diagnosed in 1995 by a parotid gland biopsy. Thoracoscopy revealed multiple discrete nodules parietally besides a number of more extensive yellowish lesions resembling malignant lymphoma. However visualization of a thoracic duct leakage was not possible. Histologically the biopsies taken represented exclusively non-caseating sarcoidosistype granulomas. Complete and permanent remission of the chylothorax was achieved within only ten days following talcum pleurodesis, alimentary measures and induction of systemic steroid therapy. The etiological classification of this extremely rare complication appears very clear. Pathogenetic and differential therapeutic aspects are discussed against the background of a review of the literature.

The image related services of the HELIOS software engineering environment.

This paper describes the approach of the European HELIOS project to integrate image processing tools into ward information systems. The image processing tools are the result of the basic research in image analysis in the Department Medical and Biological Informatics at the German Cancer Research Center. These tools for the analysis of two-dimensional images and three-dimensional data volumes with 3D reconstruction and visualization ae part of the Image Related Services of HELIOS. The HELIOS software engineering environment allows to use the image processing functionality in integrated applications.

Integrated image processing in clinical applications: the HELIOS approach.

This paper describes the approach of the European HELIOS project to integrate image processing tools into ward information systems. The image processing tools are the result of the basic research in image analysis in the Department Medical and Biological Informatics at the German Cancer Research Center. Tools for the analysis of 2-dimensional images and 3-dimensional data volumes with 3-dimensional reconstruction and visualization are part of the Image Related Services of HELIOS.

The HELIOS Image Related Services.

The HELIOS Software Engineering Environment is a tool for the construction of medical ward information systems. This paper describes the image processing tools which are a part of this system. The Image Related Services can be used both as ready-to-use end-user tools and as software modules for the construction of integrated multimedia applications. The tasks and architecture of the end-user tools and their integration into the HELIOS architecture are described. It is shown how the available image processing functionality can be used to build up new applications.

Local analgesic and vascular effects of intradermal ropivacaine and bupivacaine in various concentrations with and without addition of adrenaline in man.

Ropivacaine, a new long-acting amino-amide local anaesthetic agent, and bupivacaine, in various concentrations with or without addition of adrenaline, were tested in a randomized, double-blind study using intradermal wheals. Ten non-smoking, healthy, young male volunteers participated. In series I plain solutions of ropivacaine (0.25%, 0.5%, 0.75% and 1%) and bupivacaine (0.25%, 0.5% and 0.75%) were injected intradermally and in series II the same concentrations, with the addition of adrenaline 5 ug.ml-1 (1:200,000), were used. The same volunteers took part in both series, with an interval of at least three weeks between the experiments. Saline was included as control in both series. Pin-pricking was used to assess the dermal analgesia. Plain solutions of ropivacaine produced significantly longer durations of dermal analgesia than did plain solutions of bupivacaine, in all tested concentrations. A significant increase in duration was seen for both local anaesthetics when adding adrenaline. Local vascular effects at the injected areas were determined by visual inspection (nil, pink, pale). Local blanching (pale) was significantly more frequent for plain solutions of ropivacaine, in all tested concentrations. Local redness (pink) was significantly more frequent with plain bupivacaine, in a dose-dependent relation. An initial redness was frequently observed for both local anaesthetics containing adrenaline, followed by blanching at most sites.

Skin blood flow after intradermal injection of ropivacaine in various concentrations with and without epinephrine evaluated by laser Doppler flowmetry.

BACKGROUND AND OBJECTIVES: Skin blood flow changes after intradermal injection of ropivacaine in various concentrations with or without epinephrine were investigated using laser Doppler flowmetry. METHODS: Twenty-three non-smoking, healthy, young male volunteers participated. Four test sites were used on each forearm (volar surface) in a randomized, double-blind study. Recordings were made at 20, 40, 60, and 90 minutes after intradermal injection (0.1 ml, 30-gauge needle). Injections of saline and 1% lidocaine and an untreated area served as controls. In Series 1, various concentrations of ropivacaine (1%, 0.5%, 0.375%, 0.125%, and 0.063%) were injected. RESULTS: The data from this series showed a dose-response relationship: 1% ropivacaine provoked an increase in skin blood flow similar to saline; 0.5% and weaker concentrations of ropivacaine showed a reduction in flow compared to saline, this being more pronounced with the weakest solutions (0.125% and 0.063%). In Series 2, injection of 1:200,000 (5 micrograms/ml) epinephrine alone and injections of ropivacaine in various concentrations (1%, 0.5%, and 0.25%) with addition of epinephrine were carried out. Injection of epinephrine alone showed a flow almost as low as at the untreated control sites. Ropivacaine epinephrine injections were followed by a lower skin blood flow compared to saline, but the flow was significantly larger compared to the effect of epinephrine itself at the 20-minute recording. CONCLUSION: The combination of ropivacaine and adrenaline did not accentuate but instead diminished the vasoconstrictive effect of epinephrine.