Richard Carson, PhD
Dr. Richard Carson is with the Positron Emission Tomography Department at the Clinical Center of the National Institutes of Health.
He is a graduate of the University of California, Los Angeles (1979-1983)
earning a Ph.D. in the Department of Biomathematics, School of Medicine.
Dissertation title: Two image-wide parameter estimation methods for positron
emission tomography: theory and application to the measurement of local
cerebral blood flow in humans.
Dr. Carson's undergraduate work was from 1973 to1977 at
Brown University, Providence, RI. He earned a Sc.B. in Applied Mathematics-Biology,
graduating magna cum laude with honors.
A detailed listing of his research and a selected bibliography
appear below.
Primary ongoing projects:
Evaluation and comparison of tracers for measurements
of the 5-HT1A receptor. These studies involve the
execution and analysis of imaging studies in large animals to determine
appropriate quantification strategies and biological studies to assess the
sensitivity of these agents to changes in receptor number or changes in
endogenous serotonin. Two new tracers are currently being tested. Initial
human studies are planned for early 1999.
Quantification of muscarinic cholinergic receptors with
[18F]FP-TZTP. An M2-selective cholinergic ligand
with suitable kinetics for receptor measurement would be desirable for studies
of Alzheimer's disease. We have developed and evaluated a radioactive analog
and have recently begun human studies. Differences in M2 muscarinic receptors
between healthy young and old controls and patients with Alzheimer's disease
will be evaluated. Evaluation of the effects of muscarinic agents are also
being evaluated in non-human primates.
Characterization and optimization of the measurement
of competition between endogenous neurotransmitters and neuroreceptor ligands: The binding of neuroreceptor ligands is sensitive to the level of endogenous neurotransmitter. These studies involve the development and
testing of new models in monkeys and in human subjects. The primary application to date has been with dopamine and [11C]raclopride.
General research areas:
- Development of mathematical models to describe the uptake,
binding, and clearance of radioactive tracers. This process involves the
execution and analysis of imaging studies in large animals to determine
appropriate model configurations, devising computational methods for estimation
of physiological parameters on a regional or pixel-by-pixel basis, and
the performance of validation studies to demonstrate that the physiological
parameters of interest are measured accurately and reliably.
- Application of new and existing tracer kinetic models
to patient studies. This work involves the development of optimal methodology
for these studies. Study parameters (injection protocol, scanning and blood
sampling parameters, and data analysis algorithms) are chosen to achieve
an appropriate balance between the statistical quality of the resulting
data, patient radiation dose, and study duration. This work has lead to
the development of tracer infusion methodology for assessment of neuroreceptor
concentration and endogenous ligand release.
- Improving the quantitative accuracy of PET radioactivity
measurements. Accurate physiological measurements with PET depend on careful
correction for all the physical and statistical effects present in the
projection count data. Careful work in this area is required to avoid misinterpretation
of the PET measurements and to maximize the sensitivity of tracer methods.
Refereed papers:
- Price JC, Bacharach SL, Freedman N, Carson RE, Noise
reduction in PET attenuation correction by maximum likelihood histogram
sharpening of attenuation images, J Nucl Med, 37:786-793, 1996.
- J Cereb Blood Flow Metab, 17:932-942,
1997.
- IEEE Trans Med Imag, 16:750-761, 1997.
- Pajevic S, Daube-Witherspoon ME, Bacharach SL, Carson
RE, Noise characteristics of 3D and 2D PET images, IEEE Trans Med Imag,
17: 9-23, 1998.
- Endres CJ, Carson RE, Assessment of dynamic neurotransmitter
changes with bolus or infusion delivery of neuroreceptor ligands, J
Cereb Blood Flow Metab, in press.
- Beason-Held LL, Desmond RE, Schapiro MB, Herscovitch
P, Carson RE, Bolus injection versus slow infusion of [15O]water for PET
activation studies, J Cereb Blood Flow Metab, submitted.
- Watabe H, Endres CJ, Carson RE, Measurement of dopamine
release with [11C]raclopride and continuous infusion: Optimization and
signal-to-noise considerations, J Nuc Med, in preparation.
- Watabe H, Channing MA, Der MG, Adams HR, Jagoda E, Herscovitch
P, Eckelman WC, Carson RE, Kinetic analysis of the 5-HT 2a ligand [C-11]MDL
100,907 J Nuc Med, in preparation.
- Watabe H, Endres CJ, Carson RE, Modeling methods for
the determination of dopamine release with [11C]raclopride and constant
infusion, J Cereb Blood Flow Metabol, in preparation.
Abstracts:
- Price JC, Bacharach SL, Freedman N, Carson RE, Noise
reduction in PET attenuation correction by maximum likelihood histogram
sharpening of attenuation images, J Nucl Med, 34:27P, 1993.
- Pajevic S, Bacharach SL, Daube-Witherspoon ME, Carson
RE, Noise properties of 3D PET images, J Nucl Med, 36:105P, 1995
- Sastry S, VanMeter JW, Carson RE, Multimodality Bayesian
algorithm for image reconstruction in positron emission tomography. Conf
Record IEEE Nuclear Science Symposium and Medical Imaging Conference.
San Francisco, CA, 1995, 1694-1695
- Endres CJ, Carson RE, Kolachana B, Su T, Saunders R,
Eckelman WC, Breier A, Simultaneous modeling of {C-11]raclopride PET and
dopamine microdialysis, J Nucl Med, 37:77P, 1996.
- Endres CJ, Carson RE, Measurement of neurotransmitter
release with bolus or infusion delivery of receptor binding tracers, J
Nucl Med, 38:11P, 1997
- Endres CJ, Carson RE, Characteristics of neurotransmitter
competition studies using constant infusion of tracer, NeuroImage,
5:B74, 1997
- Watabe H, Endres CJ, Carson RE, Measurement of dopamine
release with [C-11]raclopride and continuous infusion: Optimization and
signal-to-noise considerations, J Nuc Med, 39: 55P, 1998
- Watabe H, Channing MA, Der MG, Adams HR, Jagoda E, Herscovitch
P, Eckelman WC, Carson RE, Kinetic analysis of the 5-HT 2a ligand [C-11]MDL
100,907 J Nuc Med, 39: 136P, 1998
- Watabe H, Endres CJ, Carson RE, Modeling methods for
the determination of dopamine release with [11C]raclopride and constant
infusion, Neuroimage, 7:A57, 1998.
