Long-term follow-up of mobile-bearing total ankle replacement in patients with inflammatory joint disease.

Little is known about the long-term outcome of mobile-bearing total ankle replacement (TAR) in the treatment of end-stage arthritis of the ankle, and in particular for patients with inflammatory joint disease. The aim of this study was to assess the minimum ten-year outcome of TAR in this group of patients. We prospectively followed 76 patients (93 TARs) who underwent surgery between 1988 and 1999. No patients were lost to follow-up. At latest follow-up at a mean of 14.8 years (10.7 to 22.8), 30 patients (39 TARs) had died and the original TAR remained in situ in 28 patients (31 TARs). The cumulative incidence of failure at 15 years was 20% (95% confidence interval (CI) 11 to 28). The mean American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score of the surviving patients at latest follow-up was 80.4 (95% CI 72 to 88). In total, 21 patients (23 TARs) underwent subsequent surgery: three implant exchanges, three bearing exchanges and 17 arthrodeses. Neither design of TAR described in this study, the LCS and the Buechel-Pappas, remains currently available. However, based both on this study and on other reports, we believe that TAR using current mobile-bearing designs for patients with end-stage arthritis of the ankle due to inflammatory joint disease remains justified.

Integration is the art of decomposition.

A growing demand for integrating stand-alone information systems with an HIS can be observed. Different forms of integration can be distinguished: technical integration, user interface integration, and integration of the information service. The integration of the information service appears to be especially difficult. An integrated information service can only be achieved when the applications use each other's information services. We will discuss three approaches for letting applications belonging to another system utilize the necessary information service of a host system. The first approach makes use of the user interface, and the necessary information service has to be extracted from the service to a user. Another, often used, approach is the extension of the applications with coupling modules. The coupling modules communicate messages and translate them into the context of the application. The applications are modified scarcely and the coupling modules have to supply the necessary information services. When the coupling problem is more complex (e.g., a larger set of data is to be exchanged interactively), a growing effort will be needed for these adapting modules. A better approach is to split the application into building blocks. Applications are composed of building blocks. The application, which should deliver the integrated information service, is also composed of such building blocks. The building blocks are designed to offer information services that can be used by other systems as well. If we succeed in decomposing the applications into suitable building blocks, an integrated information service could be more easily achieved.

Overview of CAPACITY data.

This paper presents an overview of the data from 15 cases collected with the CAPACITY software for cost analysis of PACS. The data suggest that both hospital wide and partial PACS implementations do not pay back yet. Only Nuclear Medicine PACS systems may be introduced cost-neutral in the near future. Because of the assumed price drop of hardware components of 5-25% per year, hospital wide and partial PACS may allow cost savings within the next 10-20 years. There are major differences in viewpoints concerning the required PACS configurations and their costs. The experiences with the CAPACITY software suggest the need for the establishment of key rules, for designing a PACS configuration and for estimating PACS costs.

An analysis of the costs of a hospital-wide Picture Archiving and Communication System with the software package CAPACITY.

Within the scope of the Dutch PACS project, the costs of a hospital wide PACS in the Utrecht University Hospital were estimated, with the help of the software package CAPACITY. The cost analysis was based on the most recent specifications of the costs of the equipment, on extrapolations, and on the experience acquired with a PACS prototype in the Utrecht University Hospital. Savings due to a possible reduction in the length of stay, or due to logistic improvements were not taken into account. The results indicate that the extra costs of a hospital wide PACS would amount to 3.2% of the total hospital budget. By taking into account the expected price movements, it is predicted that a hospital wide PACS may allow enough savings to pay itself back, when installed near the turn of the century. The result of this cost analysis depends on a large number of assumptions. Therefore two sensitivity analyses are carried out, i.e., concerning the number of workstations required and concerning the organizational impact of PACS.

A package for cost and critical analysis of picture archiving and communication indicating its true yield (CAPACITY).

The hospital-wide use of picture archiving and communication systems (PACS) promises a number of advantages in the future. These benefits will only be obtained at considerable costs, however. In view of the rapidly developing technology the costs of hardware can be expected to decrease. The ideas about the expected moment when the benefits will exceed the costs show wide variation. In order to get a better view on the cost comparison between PACS and the classical film-based system and also to stimulate discussions on this topic, a software package called CAPACITY (cost and critical analysis of picture archiving and communication indicating its true yield) has been developed by BAZIS within the scope of its IMAGIS (image information system) project. CAPACITY calculates the costs in the year of introduction for both situations, conventional and PACS, based on the consumption or use of the various resources (e.g. film, optical disks, manpower in the archive, operators, network, workstations etc.) needed for the production of the radiological department. These two costs are calculated for a series of years, thus giving an indication for the moment of breakeven. User-supplied data is interrelated and checked for plausibility against a number of expert given rules of thumb by CAPACITY's critique module. The first results and experiences acquired during a pilot study using a prototype version of the package will be discussed. The CAPACITY package is available for evaluation and trial (only distribution costs will be charged if experiences and results are returned).

Background of the demonstrated IMAGIS activities and future expectations.

In The Netherlands a national PACS development programme has been started, supported by the Dutch Society of Radiology and funded by the Dutch Department of Health because of the national character of the project. Three main partners are cooperating in this development: the Utrecht University Hospital (AZU), BAZIS and Philips International (Product Division Medical Systems), with the Delft University of Technology as the main BAZIS subcontractor. The non-profit foundation BAZIS, developing and supporting the ZIS Hospital Information System (in use in some 30 Dutch hospitals, over 15,000 acute beds), initiated its current IMAGe Information System (IMAGIS) projects in 1984. The activities were later integrated into the Dutch PACS project started in 1986. The final goal of the project is to achieve a PACS which is fully integrated with already existing hospital information systems (HIS). The development and operation of a HIS-PACS include many aspects of technical and clinical. The current efforts of BAZIS are concentrated on three main issues: diagnostic image quality evaluation (e.g. effects of data compression); modelling, software simulation and technology assessment of a prototype PACS (both general and detailed aspects); and coupling and integration of PACS and HIS (e.g. the BAZIS ZIS). Philips, Hamburg, is supplying equipment, particularly prototype components. A systematic clinical evaluation will take place at the Utrecht University Hospital.2+ We outline the background of the intermediate results as demonstrated during the 6th EuroPACS Conference:the psychophysical software package for Feature Evaluation And System Inspection By Logged Experiments (FEASIBLE); the modelling and simulation software package for Medical Image Representation, Archiving and Communication, Learned by Extensive Simulation (MIRACLES); and first results of the coupling experiments.(ABSTRACT TRUNCATED AT 250 WORDS)

HIS-PACS coupling: BAZIS/ZIS and Philips/MARCOM on speaking terms.

Nowadays a growing number of experts in the PACS field agree on the necessity of having an integrated HIS-PACS combination available in modern hospitals in order to manage the enormous amounts of patient data, both textual, numerical and image information, in an effective way. Since 1986 BAZIS (the Development and Support Group of the Hospital Information System), Philips Medical Systems and the University Hospital of Utrecht (AZU) are partners in the so-called Dutch PACS Project in the development and evaluation of a fully integrated image information system. The first phase of the coupling (sub)project consists of establishing a communication link between the BAZIS/ZIS and the Philips/MARCOM system with the following restrictions: the only data sent concerns the inpatients of one ward; data will only flow one way, from BAZIS/ZIS to Philips/MARCOM. In the second phase two-way communication will be realized and more departments can be part of the experiment. In phase 3 a more general HIS-PACS interface will be developed, independent of the manufacturers of HIS and PACS. In this paper the technical solution chosen for the first phase coupling, the format of the messages being transferred, and the events which result in sending the messages, will be described. Also, reference is made to the demonstration of the working HIS-PACS link, given during the 6th EuroPACS meeting in Utrecht and Leiden on 25-26 April 1988.