 |
| PET
scans show different patterns
of glucose (sugar) metabolism
related to performing various
mental tasks. |
Many mysteries of the human brain
have been unraveled by positron emission
tomography (PET), an imaging tool
used worldwide to diagnose cancer
and heart disease and perform scientific
studies. The development and usefulness
of PET—which offers a millionfold
greater sensitivity than other techniques
for studying regional metabolism and
neuroreceptor activity in the brain
and other tissues—rests on a
number of advances made with Office
of Science support. Much of the credit
is due to Alfred P. Wolf, a chemist
at Brookhaven National Laboratory
known as the father of organic radiochemistry,
a field that links medicine and chemistry.
In 1976, Wolf and colleagues developed
and used a radiotracer called 18-fluorodeoxyglucose
(a combination of the short-lived
radioactive element fluorine-18 and
a sugar, glucose) to generate the
first functional map of the human
brain at work. When a radiotracer
is injected into the body, its signal
is picked up by PET equipment. Glucose
is virtually the only energy source
for the brain, so images of the location
of 18-FDG provide a signature or map
of brain function. This development
enabled scientists to see, for the
first time, regions of the human brain
"lit up" in response to stimuli such
as looking, listening, and remembering.
Scientific Impact:
The development of 18-FDG, as well
as improvements in image reconstruction
algorithms and nuclear detector technologies,
enabled widespread use of PET by the
mid-1980s. Scientific uses include
studies of human metabolism, brain
activation and function, addiction,
and mental illness. Radiotracers have
also been used to track the movement
of air in the atmosphere and study
basic chemical processes.
Social Impact: Wolf's
work laid the foundation for imaging
procedures now used in hospitals worldwide
to diagnose disease, saving thousands
of lives each year. These developments
opened new vistas for mapping of human
brain function in schizophrenia, Alzheimer's
disease, stroke, addiction, and other
psychiatric and neurological disorders.
Reference: H.T.
Chugani, Phelps, M.E., "Maturational
changes in cerebral function in human
infants determined by FDG position
emission tomography," Science
231:840-843 (1986).
M.E. Phelps, Mazziotta, J.C., "Positron
emission tomography: Human brain function
and biochemistry," Science
228:799-809 (1985).
J.C. Mazziotta, Phelps, M.E., Carson,
R.E., "Tomographic mapping of human
cerebral metabolism: Subcortical responses
to auditory and visual stimulation,"
Neutol.,34:825-828 (1984).
M. Reivich, Kuhl, D., Wolf, A.P.,
Greenberg, J., Phelps, M., Ido, T.,
Casella, V., Fowler, J., Hoffman,
E., Alavi, A., Som, P., and L. Sokoloff,
"The (18F) Fluorodeoxyglucose Method
for the Measurement of Local Cerebral
Glucose Utilization in Man," Circulation
Research 44:127-137 (1979).
URL: http://www.nuc.ucla.edu
http://www.crump.ucla.edu
Technical Contact:
Dr. Prem Srivastava, Medical Sciences
Division, Office of Biological and
Environmental Research, 301-903-4071
Press Contact: Jeff
Sherwood, DOE Office of Public Affairs,
202-586-5806
SC-Funding Office:
Office of Biological and Environmental
Research |
