One of the areas that have taken profit most of the digital management of clinical data is medical imaging. The appearance of the Digital Imaging and Communication in Medicine standard (DICOM), has envolved throughout the years to support not only medical images but also other types of medical information like videos, signals and even structured reports (DICOM-SR). DICOM has enabled the acquisition, visualization, printing and storage devices for medical images of different manufacturers.
Today, systems working with medical digital image, such as PACS, RIS and HIS, integrate effectively the information at department and hospital level. In these systems, the security of users and information is managed only in a single administrative restricted domain. Moreover, a result of its use in production in the clinical practice is a huge quantity of information available in DICOM format, but it is used only for treatment of individual patients. Nevertheless, the medical research needs to consolidate multicentral information for the extraction of patterns and the validation of procedures and diagnostics, performing currently this activity manually and without special tools.
In this thesis, the main objective is the definition of a Service Oriented Architecture (SOA) and the implementation of a Grid Middleware based on this architecture, whose principal function will be the management, integration and process of DICOM information stored in a secure and distributed way in different administrative domains, and constructed semantically by means of the definition of medical ontologies based on the structured reports and DICOM studies. This middleware, provides the developers with a high-level object-oriented interface that increases the productivity in the development of applications in different medical areas.
The most important contributions of this thesis are the following:
•	Design of a general Grid Architecture Grid to virtualize a distributed storage for the processing of DICOM information, based on Web Services Resource Framework (WSRF), extending the possibilities of other architectures that do not use standards.
•	Development of a model for the indexation and structuring of DICOM information based on medical ontologies obtained from radiological reports, as an advance to the conventional models based on clinical keys and basic metadata.
•	Design and implementation of an authorization system that organizes the permissions of the virtual organizations users using medical ontologies.
•	Implementation of a platform and of the high-level objects required, along with diverse applications for the assistance in the research in image diagnosis.