Kinetic Parameter Imaging with Dynamic PET
Kinetic parameter estimation with Dynamic Positron Emission Tomography (PET) has
a wide range of applications ranging from tumor studies to drug delivery. Estimation of the parameters
require that the blood input function is known. Clasically, this is performed with
arterial sampling which poses helath risks, require extra time and personnel, and also
very difficult for especially small animal experiments.
We develop methods that eliminate the need of known blood function. The blood function
is estimated simultaneously based on the sinogram directly for a better accuracy as opposed
to the reconstructed images.
The blood input function is accurately estimated with the proposed method (solid: arterial sampling, dashed: estimated).
This eliminates the need for arterial sampling with dynamic PET studies.
We have also developed methods based on the method of moments (MOM) to tackle the problem of local
minima with dynamic PET. Our MOM algorithm can be used both as an approximate estimate or to initialize
the iterative algorithms to avoid local minima.
We observe that MSE does not change significantly and the problem of non-convergent results is successfully
removed.
The 28 datasets are collected from mice as part of a drug delivery study.
MOM: method of moments, CGM: conjugate gradient method, CGM MOM: CGM initialized with MOM, RFIT:
RFIT developed at Lawrence Berkeley Lab,
RFIT MOM: RFIT initialized with MOM.
References:
- Y. Cheng, I. S. Yetik, "Propagation of blood function error to the final kinetic parameter
estimates with dynamic PET", submitted.
- M. Gadiya, I. S. Yetik, "Direct reconstruction of kinetic parameter images with ordered subsets", Proceedings of Medical Imaging Conference, 2008.
- F. Pektas, I. S. Yetik, "Covariance expressions for implicit estimators of kinetic parameters with dynamic PET ", Proceedings of IEEE Electro/Information Technology , pp. 316-320,2008.
- Y. Cheng, I. S. Yetik, "Effect of the blood function error on the estimated kinetic parameters with dynamic PET",
Proceedings of IEEE International Symposium on Biomedical Imaging, pp. 1585-1588, 2008.
- I. S. Yetik, J. Qi, "Direct estimation of kinetic parameters from the sinogram with an unknown blood function", Proceedings of IEEE International Symposium on Biomedical Imaging, pp. 295-298, 2006.
- I. S. Yetik, J. Qi, "A fast method for kinetic parameter estimation" Proceedings of IEEE Nuclear Science Symposium , pp. 3213-3216, 2006.
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