Distributed PACS using Network Shared File System

In this paper, a distributed PACS (Picture Archiving and Communication Systems) using a network shared file system is proposed. Several distributed hospitals and sites use PACS to manage medical images. For these distributed sites to work together, it is necessary to construct integrated PACS for these distributed files. In the proposed system, the DICOM (Digital Imaging and Communications in Medicine) metadata and the DICOM image data are registered separately on the server. In the proposed system, several operations can be performed using only the metadata. For example, images can be searched using only the information stored in the metadata, and therefore the client can find the target image without downloading the whole DICOM data. DICOM image size is usually huge. Therefore, if a file can be found or transformed without downloading the whole data, the file operation can be performed very quickly. To implement the proposed system, the open source Gfarm network shared file system, which treats metadata as XML data, was used. This paper describes construction of the proposed system, and discusses experimental comparison of Gfarm and NFS with regard to transfer rates.