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Published on: December 28, 2013
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Quantification of Dynamic 11C-Phenytoin PET Studies
Syahir Mansor1, Ronald Boellaard2, Femke E Froklage3
1Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands m.mansor@vumc.nl.
Summary
A reversible single-tissue-compartment model with blood volume is optimal for quantifying (11)C-phenytoin PET scans in humans. Shorter scan times of 45 minutes maintain accuracy for P-glycoprotein (Pgp) studies.
Area of Science:
- Neuroscience
- Pharmacology
- Radiochemistry
Background:
- P-glycoprotein (Pgp) overexpression is a key factor in epilepsy pharmacoresistance.
- (11)C-phenytoin is a promising PET tracer for assessing Pgp activity.
Purpose of the Study:
- To determine the optimal plasma kinetic model for quantifying (11)C-phenytoin PET studies in humans.
- To evaluate the test-retest variability of kinetic parameters.
Main Methods:
- Dynamic (11)C-phenytoin PET scans were performed on 6 healthy volunteers with arterial sampling.
- Data were analyzed using single- and 2-tissue-compartment models, with and without a blood volume parameter.
- Test-retest variability for K1 and VT was assessed globally and regionally.
Main Results:
- The reversible single-tissue-compartment model with a blood volume parameter was identified as the preferred model.
- Mean test-retest variability ranged from 1.5% to 16.9% for K1 and 0.5% to 5.8% for VT.
- Scan duration could be reduced to 45 minutes without significant loss of accuracy or precision for K1 and VT.
Conclusions:
- A reversible single-tissue-compartment model with blood volume is suitable for quantifying dynamic (11)C-phenytoin PET studies.
- Scan duration can be shortened to 45 minutes, offering potential efficiency gains, pending confirmation in pathological conditions.
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