NATIONAL INSTITUTES OF HEALTH
National Library of Medicine
The Visible Human Project
NLM's Lister Hill National Center for Biomedical Communications has
been conducting research into digital imaging for several years. A
major effort in this area, the Visible Human Project, intends to
create, for health professions education, treatment, and research,
complete anatomically detailed, three-dimensional representations of
the male and female human body.
The Visible Human Project has its roots in the Library's 1986 Long-
Range Plan. The plan recommended that the NLM should "...thoroughly
and systematically investigate the technical requirements for and
feasibility of instituting a biomedical images library." It
encouraged the NLM to consider building and disseminating medical
image libraries much the same way it acquires, indexes, and provides
access to the biomedical literature. It foresaw a coming era where
NLM's bibliographic and factual database services would be
complemented by libraries of digital images, distributed over high-
speed computer networks and by high-capacity physical media. Not
surprisingly, it saw an increasing role for electronically
represented images in clinical medicine and biomedical research.
Early in 1989, under the direction of the Board of Regents, an ad hoc
planning panel was convened to explore the proper role for the NLM in
the rapidly changing field of electronic imaging. After much
deliberation, the NLM Planning Panel on Electronic Image Libraries
made the following recommendation: "NLM should undertake a first
project building a digital image library of volumetric data
representing a complete, normal adult male and female. This Visible
Human Project will include digitized photographic images for
cryosectioning, digital images derived from computerized tomography
and digital magnetic resonance images of cadavers ."
The current effort under the Visible Human Project is the acquisition
of transverse CT, MRI and cryosection images of a representative male
and female cadaver at an average of one millimeter intervals. The
corresponding transverse sections in each of the three modalities are
to be registered with one another. A contract for acquisition of
these pixel-based data was awarded in August 1991 to the University
of Colorado at Denver. Victor M. Spitzer, Ph.D. and David G.
Whitlock, M.D., Ph.D. are the principal investigators. The Visible
Human data set will comprise approximately 42 gigabytes of pixel data
(uncompressed), which would correspond to about 70 CD-ROMs. The
digital cross-sectional images would most likely be made available
via the Internet.
The larger, long-term goal of the Visible Human Project is to produce
a system of knowledge structures that will transparently link visual
knowledge forms to symbolic knowledge formats. Methods need to be
developed to link image data to such text-based data as names,
hierarchies, principles and theories. Standards do not currently
exist for such linkages. The project is experimenting with methods
that have wide application, like the use of hypermedia where words
can be used to find pictures, and pictures can be used as an index
into relevant text. Basic research is needed in the description and
representation of structures, and the connection of structural-
anatomical to functional-physiological knowledge. The goal is to
make the print library and the image library a single, unified
resource for medical information.
For additional information on the Visible Human Project please
Dr. Michael J. Ackerman
Project Officer, Visible Human Project
National Library of Medicine
8600 Rockville Pike
Bethesda, MD 20894
 National Library of Medicine (U.S.) Board of Regents.
Electronic imaging: Report of the Board of Regents. U.S. Department
of Health and Human Services, Public Health Service, National
Institutes of Health, 1990. NIH Publication 90-2197.