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1.
AJNR Am J Neuroradiol ; 40(3): 568-575, 2019 03.
Article in English | MEDLINE | ID: mdl-30819765

ABSTRACT

BACKGROUND AND PURPOSE: HERBY was a Phase II multicenter trial setup to establish the efficacy and safety of adding bevacizumab to radiation therapy and temozolomide in pediatric patients with newly diagnosed non-brain stem high-grade gliomas. This study evaluates the implementation of the radiologic aspects of HERBY. MATERIALS AND METHODS: We analyzed multimodal imaging compliance rates and scan quality for participating sites, adjudication rates and reading times for the central review process, the influence of different Response Assessment in Neuro-Oncology criteria in the final response, the incidence of pseudoprogression, and the benefit of incorporating multimodal imaging into the decision process. RESULTS: Multimodal imaging compliance rates were the following: diffusion, 82%; perfusion, 60%; and spectroscopy, 48%. Neuroradiologists' responses differed for 50% of scans, requiring adjudication, with a total average reading time per patient of approximately 3 hours. Pseudoprogression occurred in 10/116 (9%) cases, 8 in the radiation therapy/temozolomide arm and 2 in the bevacizumab arm (P < .01). Increased target enhancing lesion diameter was a reason for progression in 8/86 cases (9.3%) but never the only radiologic or clinical reason. Event-free survival was predicted earlier in 5/86 (5.8%) patients by multimodal imaging (diffusion, n = 4; perfusion, n = 1). CONCLUSIONS: The addition of multimodal imaging to the response criteria modified the assessment in a small number of cases, determining progression earlier than structural imaging alone. Increased target lesion diameter, accounting for a large proportion of reading time, was never the only reason to designate disease progression.


Subject(s)
Brain Stem Neoplasms/diagnostic imaging , Clinical Trials, Phase II as Topic , Glioma/diagnostic imaging , Multimodal Imaging , Neuroimaging , Bevacizumab/therapeutic use , Brain Stem Neoplasms/pathology , Brain Stem Neoplasms/therapy , Chemoradiotherapy/methods , Child , Clinical Trials, Phase II as Topic/methods , Disease Progression , Disease-Free Survival , Female , Glioma/pathology , Glioma/therapy , Humans , Male , Multicenter Studies as Topic/methods , Multimodal Imaging/methods , Randomized Controlled Trials as Topic/methods , Temozolomide/therapeutic use
2.
AJNR Am J Neuroradiol ; 37(9): 1581-7, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27127006

ABSTRACT

Determination of tumor response to treatment in neuro-oncology is challenging, particularly when antiangiogenic agents are considered. Nontumoral factors (eg, blood-brain barrier disruption, edema, and necrosis) can alter contrast enhancement independent of true tumor response/progression. Furthermore, gliomas are often infiltrative, with nonenhancing components. In adults, the Response Assessment in Neuro-Oncology (RANO) criteria attempted to address these issues. No such guidelines exist yet for children. The ongoing randomized phase II trial, A Study of Avastin (bevacizumab) in Combination With Temolozomide (TMZ) and Radiotherapy in Paediatric and Adolescent Patients With High-Grade Glioma (HERBY), will establish the efficacy and safety of the antiangiogenic agent bevacizumab for the first-line treatment of newly diagnosed high-grade glioma in children (n = 121 patients, enrollment complete). The primary end point is event-free survival (tumor progression/recurrence by central review, second primary malignancy, or death). Determination of progression or response is based on predefined clinical and radiographic criteria, modeled on the RANO criteria and supported by expert pseudoprogression review and the use of standardized imaging protocols. The HERBY trial will also compare conventional MR imaging (T1-weighted and T2/fluid-attenuated inversion recovery sequences) with conventional MR imaging plus diffusion/perfusion imaging for response assessment. It is anticipated that HERBY will provide new insights into antiangiogenic-treated pediatric brain tumors. HERBY will also investigate the practicality of obtaining adequate quality diffusion/perfusion scans in a trial setting, and the feasibility of implementing standard imaging protocols across multiple sites. To date, 61/73 (83.6%) patients with available data have completed diffusion-weighted imaging (uptake of other nonconventional techniques has been limited). Harmonization of imaging protocols and techniques may improve the robustness of pediatric neuro-oncology studies and aid future trial comparability.


Subject(s)
Brain Neoplasms/diagnostic imaging , Diffusion Magnetic Resonance Imaging/methods , Glioma/diagnostic imaging , Adolescent , Adult , Angiogenesis Inhibitors/therapeutic use , Bevacizumab/therapeutic use , Brain Neoplasms/drug therapy , Brain Neoplasms/pathology , Child , Disease Progression , Disease-Free Survival , Female , Glioma/drug therapy , Glioma/pathology , Humans , Magnetic Resonance Imaging , Male
3.
Diabet Med ; 22(6): 794-802, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15910634

ABSTRACT

AIMS: TOSCA was an EU-Commission supported international research project designed to develop telescreening services in diabetic retinopathy and glaucoma. This paper describes the quality assurance methods developed for the diabetic retinopathy telescreening service within the TOSCA project. SETTING: The study was performed in 1895 patients with diabetes between 2000 and 2002 at diabetic retinopathy screening sites in five European countries. Data were analysed centrally. METHODS: Patients attending each clinic's diabetic retinopathy screening service received standardized retinal photography. The images and associated data were transferred electronically to a remote location for grading. Each photographer uploading images and each grader downloading images for assessment was controlled by a systematic quality management approach. The quality assurance measures defined were image quality, intragrader reliability. A cockpit chart was developed for the management and presentation of relevant results and quality measures. For the intragrader reliability tests, 10% of the images were processed for a second grading. An algorithm for calculating differences between repeated gradings was developed. RESULTS: The assessment of image quality for the different sites showed that only 0-0.7% were unassessable. One hundred per cent agreement for both gradings was achieved in 50-85% of graded cases, depending on site and grader, and an agreement better than 95% in 71-100% of cases. CONCLUSIONS: A telemedicine-supported quality assurance process is practical and advantageous. The cockpit charts have proven to be useful tools when monitoring the performance of a telescreening service. Grader feedback showed high satisfaction with the quality assurance process.


Subject(s)
Diabetic Retinopathy/diagnosis , Telemedicine/standards , Vision Screening/methods , Humans , Mass Screening , Quality Assurance, Health Care , Telemedicine/instrumentation
4.
Methods Inf Med ; 43(4): 409-12, 2004.
Article in English | MEDLINE | ID: mdl-15472755

ABSTRACT

INTRODUCTION: The lack of comparability of evaluation results is one of the major obstacles of research and development in Medical Image Processing (MIP). The main reason for that is the usage of different image datasets with different quality, size and Gold standard. OBJECTIVES: Therefore, one of the goals of the Working Group on Medical Image Processing of the European Federation for Medical Informatics (EFMI WG MIP) is to develop first parts of a Reference Image Database. METHODS: Kernel of the concept is to identify highly relevant medical problems with significant potential for improvement by MIP, and then to provide respective reference datasets. The EFMI WG MIP has primarily the role of a specifying group and an information broker, while the provider user relationships are defined by bilateral co-operation or license agreements. RESULTS: An explorative database prototype has been implemented using the MySQL database software on the Web. Templates for provider user agreements have been worked out and already applied for own 'pre-RID-MIP' co-operations of the authors. DISCUSSION AND CONCLUSION: First steps towards a comprehensive reference image database have been done. Issues like funding, motivation, management, provision of Gold standards and evaluation guidelines are to be solved. Due to the interest from research groups and industry the efforts will be continued.


Subject(s)
Databases as Topic , Diagnostic Imaging/standards , Image Processing, Computer-Assisted , International Cooperation , Medical Informatics Applications , Research , Humans , Quality Assurance, Health Care
5.
Diabet Med ; 21(10): 1121-8, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15384960

ABSTRACT

AIMS: The TOSCA project was set up to establish a tele-ophthalmology service to screen for diabetic retinopathy (DR) in Europe. The aim of this study was to determine the feasibility of establishing telemedicine-based digital screening for detecting DR and to evaluate the satisfaction of both patients and healthcare professionals with the screening procedures used within the TOSCA project. METHODS: The study was a non-randomized, multicentre study carried out in four different countries over a period of 3 months. Patients (n = 390) with diabetes aged > 12 years were included. Two digital retinal images per eye (macular and nasal) were taken and exported to a central server. Patients were asked to complete a questionnaire to assess satisfaction. Accredited graders carried out grading remotely and the results were reported back to the referring centre. Previously graded patient data chosen randomly to represent examples of both DR and no DR were also sent anonymously to the grading centre at a frequency of approximately every 10 patients. RESULTS: Most (99%) of the images were assessable enabling a retinopathy grade to be assigned to the patient. Patients found the retinal photography procedures acceptable; only 6% in one centre would not recommend the procedure. Healthcare professionals (photographers and graders) were also satisfied with the overall procedures. The average time taken to grade each patient was approximately 5 min. CONCLUSIONS: This study demonstrated that it is feasible to electronically transmit and grade retinal images remotely using the TOSCA process. Built-in quality assurance procedures proved acceptable.


Subject(s)
Diabetic Retinopathy/diagnosis , Photography/instrumentation , Telemedicine/instrumentation , Adolescent , Aged , Aged, 80 and over , Feasibility Studies , Female , Humans , Male , Middle Aged , Quality Assurance, Health Care , Surveys and Questionnaires
6.
J Biomed Inform ; 37(1): 30-42, 2004 Feb.
Article in English | MEDLINE | ID: mdl-15016384

ABSTRACT

In this paper, we review the results of BIOINFOMED, a study funded by the European Commission (EC) with the purpose to analyse the different issues and challenges in the area where Medical Informatics and Bioinformatics meet. Traditionally, Medical Informatics has been focused on the intersection between computer science and clinical medicine, whereas Bioinformatics have been predominantly centered on the intersection between computer science and biological research. Although researchers from both areas have occasionally collaborated, their training, objectives and interests have been quite different. The results of the Human Genome and related projects have attracted the interest of many professionals, and introduced new challenges that will transform biomedical research and health care. A characteristic of the 'post genomic' era will be to correlate essential genotypic information with expressed phenotypic information. In this context, Biomedical Informatics (BMI) has emerged to describe the technology that brings both disciplines (BI and MI) together to support genomic medicine. In recognition of the dynamic nature of BMI, institutions such as the EC have launched several initiatives in support of a research agenda, including the BIOINFOMED study.


Subject(s)
Computational Biology/methods , Delivery of Health Care/methods , Genetic Testing/methods , Genetic Therapy/methods , Genomics/methods , Medical Informatics/methods , Research Design , Biotechnology/methods , Biotechnology/trends , Computational Biology/trends , Delivery of Health Care/trends , European Union , Forecasting , Gene Expression Profiling/methods , Gene Expression Profiling/trends , Genetic Testing/trends , Genetic Therapy/trends , Genomics/instrumentation , Government Programs , Medical Informatics/trends , Research/trends , Technology Assessment, Biomedical
7.
Langenbecks Arch Surg ; 385(3): 162-70, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10857486

ABSTRACT

The risk involved in partial liver resections depends mainly on tumor localization, invasion of central vascular structures, and parenchymal function. The imaging techniques available today (computed tomography, magnetic resonance imaging) allow us to detect precisely the extent of tumor invasion and their relationship to central vessels. The various three-dimensional reconstruction techniques are helpful with regard to a virtual planning of liver resections. The calculation of remaining liver volumes subsequent to partial hepatectomies are considered to be an essential predictive parameter in terms for the development of postoperative liver failure. In a retrospective and a later consecutive, prospective clinical study we analyzed the postoperative risk in a series of 570 patients. In an univariate analysis 13 of 31 parameters showed significant values. In multivariate analysis only three parameters (partial hepatic resection rate, PHRR), gamma-glutamyltranspeptidase, and prothrombin activity) were independent parameters for predicting liver failure, generating the most significant values for the PHRR. In our experience the most comfortable and precise technique for evaluating PHRR is the b-spline technique.


Subject(s)
Image Processing, Computer-Assisted , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Tomography, X-Ray Computed , Female , Hepatectomy/adverse effects , Humans , Liver Failure/etiology , Liver Neoplasms/enzymology , Liver Neoplasms/pathology , Logistic Models , Male , Patient Care Planning , Postoperative Complications , Predictive Value of Tests , Prospective Studies , Prothrombin Time , Retrospective Studies , Risk Assessment , Risk Factors , gamma-Glutamyltransferase/metabolism
11.
IEEE Trans Inf Technol Biomed ; 3(2): 84-91, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10719489

ABSTRACT

With the rapidly increasing development of telemedicine technology, the evaluation of telemedical services becomes more and more important. However, professional views of the aims and methods of evaluation are different from the perspective of computer science and engineering or from medicine and health policy. We propose that a continuous evaluation strategy should be chosen which guides the development and implementation of telemedicine technologies and applications. The evaluation strategy is divided into four phases in which the focus of evaluation is shifted from technical performance of the system in the early phases to medical outcome criteria and economical aspects in later phases. We review the study design methodology established for clinical trials assessing therapeutic effectiveness and diagnostic accuracy and discuss how it can be adapted to evaluation studies in telemedicine. As an example, we describe our approach to evaluation in a teleconsultation network in ophthalmology.


Subject(s)
Telemedicine/standards , Evaluation Studies as Topic , Ophthalmology , Process Assessment, Health Care
12.
Klin Monbl Augenheilkd ; 212(2): 111-5, 1998 Feb.
Article in German | MEDLINE | ID: mdl-9577811

ABSTRACT

MOTIVATION: Telemedical services for ophthalmology are developed within the OPHTEL project, which has been funded by the European Union and by the Bavarian government in the Bavaria-online initiative. METHODS: Seven private ophthalmologists, one university eye clinic, one clinical Diabetes center and an informatics research institute are connected within a teleconsultation network. Asynchronous (based on Internet E-Mail) and synchronous (based on ISDN-mediated videoconferencing tools) types of teleconsultations are realized. RESULTS: 86 teleconsultations (62 asynchronous, 23 synchronous) took place within the first 10 months. Complex and rare eye diseases as well as interdisciplinary questions (ophthalmology--diabetology) are the main area of medical communication interest. Legal and security problems are discussed. CONCLUSIONS: Telemedical services must be understood as a complete process of medical care on the basis of modern communication technologies, which influences also the management of this process.


Subject(s)
Computer Communication Networks , Ophthalmology , Remote Consultation , Computer Communication Networks/instrumentation , Computer Security/legislation & jurisprudence , Computer Systems , Germany , Humans , Ophthalmology/instrumentation , Patient Care Team , Remote Consultation/instrumentation
13.
Ophthalmologe ; 94(7): 523-8, 1997 Jul.
Article in German | MEDLINE | ID: mdl-9333401

ABSTRACT

BACKGROUND: In Denmark, France, Germany, Great Britain and Italy, the OPHTEL project combines clinical centers of ophthalmology and internal medicine, an institute for medical informatics and health services research, a publishing company and different industrial partners in the EDP market. AIMS: With the aid of visual telecommunication and rapid data transfer, methods and conditions will be developed and proved so that any physician can very easily obtain sufficient information for treating his patient. Thus, the regional differences in the quality of structured health service (e.g., urban/ rural) will be overcome throughout Europe. SCIENTIFIC TASKS: A multilingual diagnostic and therapeutic thesaurus has to be worked out in order to create standards for communication and quality control. Based on literature, images and image analysis in a knowledge-based data bank, a monitoring system (containing watch-dog functions) and the basic aspects of an ophthalmological patient/disease register will be investigated. (In parallel, a technical development of synchronous and asynchronous telecommunication between eye physicians is taking place in close cooperation with the regional Bavarian project Teleopathalmology in Bavaria on-line). RESULTS: State of the art 6 months after starting the project:the knowledge-based image data bank has been founded and also an ophthalmological 8 language thesaurus and definition standard. All data transfer lines are installed. DISCUSSION: The project is taking place amid diverging sections of medicine: ophthalmology and internal medicine, health politics and data protection, individual treatment and common interest (health care), product management and office organization. Thus, the scientific quality of the transferred ophthalmological content must undergo sophisticated controls. FUTURE STEPS: Intense cooperation with the big German associations for ophthalmology (DOG, BVA) and the European ophthalmological societies concerning EDP, classification and quality control.


Subject(s)
Computer Communication Networks/instrumentation , Ophthalmology/instrumentation , Remote Consultation/instrumentation , Europe , Germany , Humans , Medical Records Systems, Computerized/instrumentation , Patient Care Team , Quality Control
14.
Comput Methods Programs Biomed ; 32(3-4): 297-301, 1990.
Article in English | MEDLINE | ID: mdl-2249428

ABSTRACT

DIABETEX is a knowledge-based, computer-supported consultation system for the therapy of type I diabetic out-patients. Three knowledge bases contain the medical and technical knowledge for treating either adults, adolescents or children by means of injections or by pumps. For the evaluation of the quality of the decision proposals three groups of patients were studied. The results obtained in test phase 1, i.e. the retrospective evaluation of DIABETEX decision proposals by the experts, and in test phase 2, i.e. the parallel work of DIABETEX and of an expert and the subsequent evaluation by experts, provide the basis for the further development and application of the system by non-expert diabetologists.


Subject(s)
Diabetes Mellitus, Type 1/therapy , Expert Systems , Software , Therapy, Computer-Assisted , Adolescent , Child , Decision Support Techniques , Diabetes Mellitus, Type 1/metabolism , Drug Administration Schedule , Female , Glycated Hemoglobin/metabolism , Humans , Insulin/administration & dosage , Male , Middle Aged , Retrospective Studies , Software Design
15.
Comput Methods Programs Biomed ; 32(3-4): 333-7, 1990.
Article in English | MEDLINE | ID: mdl-2249433

ABSTRACT

Current research in the field of medical decision making tries to represent and to analyse complex, uncertain and complicated situations. The first version of DIABETEX, which is a decision support system for the treatment of diabetic out-patients, accepts the challenge to overcome these difficulties. It includes a network of rules on the basis of known glucose-insulin relationships under different situations. The insulin dose for type I diabetic patients is suggested accordingly. In this, the application of special cybernetic methods offers the chance to overcome complexity, uncertainty, fuzzyness and incompleteness of data. Two methods of classification are presented to complete the DIABETEX decision unit: (1) the Bayes' classification is used in the calculation of insulin doses for type I diabetic patients on multiple subcutaneous insulin injections considering the basis-bolus concept; (2) fuzzy classification is employed in separating 'normal diabetic days' from days with information on special situations such as exercise, illness, menstruation on the one side, from stress, hypoglycaemia etc. on the other.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Insulin/administration & dosage , Software , Bayes Theorem , Blood Glucose/metabolism , Diabetes Mellitus, Type 1/metabolism , Drug Administration Schedule , Eating/physiology , Expert Systems , Humans
16.
Stomatol DDR ; 40(3): 115-6, 1990 Mar.
Article in German | MEDLINE | ID: mdl-2284654

ABSTRACT

The increase of quality and efficiency in orthodontic treatment is characterized by the development of knowledge based consultations systems. These systems support the dentist to optimate treatment planing. Basis configuration and technical background of those systems are presented.


Subject(s)
Databases, Factual , Expert Systems , Orthodontics , Diagnosis, Computer-Assisted , Humans , Microcomputers , Therapy, Computer-Assisted
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