As prototype PACS grow into fully digital departmental and hospital-wide systems, effective
information storage and retrieval mechanisms become increasingly important. Thus far, designers of
PACS workstations have concentrated on image communication and display functionality. The new
challenge is to provide appropriate operator interface environments to facilitate information retrieval.
The "Marburg Model" 1 provides a detailed analysis of the functions, control flows and data
structures used in Radiology. It identifies a set of "actors" who perform information manipulation
functions. Drawing on this model and its associated methodology it is possible to identify four modes of
use of information systems in Radiology: Clinical Routine, Research, Consultation, and Administration.
Each mode has its own specific access requirements and views of information. An operator interface
strategy appropriate for each mode will be proposed.
Clinical Routine mode is the principal concern of PACS primary diagnosis workstations. In a full
PACS implementation, such workstations must provide a simple and consistent navigational aid for the
on-line image database, a local work list of cases to be reviewed, and easy access to information from
other hospital information systems. A hierarchical method of information access is preferred because it
provides the ability to start at high-level entities and iteratively narrow the scope of information from
which to select subsequent operations. An implementation using hierarchical, nested software windows
which fulfills such requirements shall be examined.