MacRad: Radiology Image Resource
with a Case-Based Retrieval System

Robert T. Macura, M.D., Ph.D.
Katarzyna J. Macura, M.D., Ph.D.

Medical Informatics Section, Department of Radiology
Medical College of Georgia, Augusta GA 30912, U.S.A.


Abstract

We have compiled a case-based retrieval system for radiology, MacRad, that is structured
around descriptors for radiology image findings. Our goal is to provide a feature-coded image
resource that allows the user to formulate image content-based queries when searching for
reference images. MacRad is implemented as a relational database with an image archive.
Each image in the library is indexed according to its radiologic content. We structured an
index for coding image content as a hierarchical image description index using the relational
format. The hierarchical index of radiologic findings allows multilevel query formulation that
depends upon the users level of experience. The system uses rules to control the search
direction within the case library and generate lists of diagnostic hypotheses for decision
support. Rules are embedded within the database structure. At present, the case library consists
of 300 cases and 3,000 images that present intracranial masses on skull X-rays, CTs, MRIs.
and angiograms.
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