                             NATIONAL INSTITUTES OF HEALTH
                            National Library of Medicine
APRIL 1993                              

                            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.
  
  Background
  
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 [1]."
  
  Current Status
  
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
    contact:
  
       Dr. Michael J. Ackerman
       Project Officer, Visible Human Project
       National Library of Medicine
       8600 Rockville Pike
       Bethesda, MD 20894
  
[1]  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.
