Modeling ad-hoc medical imaging workflows with BPEL4WS

2 Medical Imaging
In this section a brief introduction to the medical imaging domain is provided. A more detailed discussion can be found in [8], [9], [10], [11] and [12]. Next, two sample workflows are introduced to be inspected further. 2.1 HIS, RIS and PACS Three systems, the HIS (Hospital Information System) [13], the RIS (Radiology Information System) [12] and the PACS (Picture Achieving and Communication system) [10] are the backbone of current information systems in the hospital and medical imaging environment, comparable to ERP (Enterprise Resource Planning) and SCM (Supply Chain Management) systems. The HIS is an enterprise-wide system mostly used for administrative tasks like patient and visit management, bed reservations, patient referrals, operation planning, other scheduling tasks and billing management. The RIS is a patient- management system required for all organizational tasks of a medical imaging facility (whether in- or outside a hospital) like examination scheduling, patient registration, worklist generation, examination control, report generation (using digital dictation equipment and speech recognition) report transcription and
Modeling ad-hoc medical imaging workflows with BPEL4WS
Rainer Anzböck1, Schahram Dustdar2, and Masoud Gholami3
1, 3 D.A.T.A. Corporation, Invalidenstrasse 5-7/10, 1030 Wien, Austria {ar|gm}@data.at 2 Distributed Systems Group, Vienna University of Technology Argentinierstrasse 8/184-1, 1040 Wien, Austria dustdar@infosth recent work in the field of ad-hoc workflows it is possible to define more flexible business models than in traditional workflows based on the Workflow reference model (WFMC) [1]. With the standardization of the Business Process Execution Language (BPEL4WS, short BPEL) [2] a new implementation method for Web service based scenarios is available. The medical imaging domain is currently in a dynamic evolution to digitally connected networks. Standardization in the field of medical imaging has been covered by the HL7 [3] and DICOM [4] standards. A related standardization process for health informatics is enforced by the European Union with the CEN/TC 251 work program [5] which is out of the scope of this paper but is recognized as an important research area. The goal of this paper is to analyze a highly relevant ad-hoc workflow [6] in the medical imaging domain: the second opinion workflow. Since this workflow, by its nature, involves other (increasingly ubiquitous) information systems (e.g. imaging
equipment), it may serve as a test case for the applicability and suitability of BPEL in the medical imaging domain. The workflow model covers implementation relevant aspects of the DICOM and HL7 protocol while maintaining an abstract domain model. The contribution of this paper is as follows: First it introduces current research issues in loosely coupled ad-hoc workflow models and defines a formal basis for simple workflow pattern. Secondly, it provides a separation of a basic workflow and the extended ad-hoc (second opinion) workflow. In the next step it abstracts the communication protocols by implementing sub-workflows for the service interfaces. Furthermore we analyze mapping problems between the workflow and the communication layer and point out the relationships to ad-hoc workflow specifications for the medical imaging domain. Finally we provide a WSDL [7] and BPEL specification of the second opinion workflow. To summarize, our paper (i) analyzes the second opinion ad-hoc workflow in the medical imaging domain and analyzes the requirements for modeling such workflows, (ii) suggests flexible communication semantics not covered in recent work of workflow management and Web services technology and (iii) investigates whether the current BPEL definition is applicable and suitable for the medical imaging domain. The paper is structured as follows. Section 2 introduces ad-hoc workflows and provides definitions of workflow patterns. Section 3 provides an introduction to. Section 4 introduces the ad-hoc workflow and its ad-hoc mechanism required for modeling. Section 5 discusses the relationship between the workflow model and the implementation protocols and suggests a mapping terminology. It extends the discussion to current standardization processes. Section 6 concludes the results and provides information about related work.