StudyCentric is web-based DICOM image viewer for use with research applications. The application communicates with a DICOM PACS via the DICOM protocol (both standard DICOM C-FIND queries and via WADO). The standard DICOM communication is executed using a very small Ruby web-service (the server). The application runs entirely in the web browser except for a small server component available in Python or Ruby.
StudyCentric not a full PACS viewer, it is meant to be deployed within a larger application to view specific DICOM studies. It contains no patient or image search functionality.