Autor: |
Zanderigo, Francesca, Kang, Yeona, Kumar, Dileep, Nikolopoulou, Anastasia, Mozley, P. David, Kothari, Paresh J., He, Bin, Schlyer, David, Rapoport, Stanley I., Oquendo, Maria A., Vallabhajosula, Shankar, Mann, J. John, Sublette, M. Elizabeth |
Zdroj: |
Synapse; Feb2018, Vol. 72 Issue 2, pn/a-1, 13p |
Abstrakt: |
Arachidonic acid (AA) is involved in signal transduction, neuroinflammation, and production of eicosanoid metabolites. The AA brain incorporation coefficient (K*) is quantifiable in vivo using [11C]AA positron emission tomography, although repeatability remains undetermined. We evaluated K* estimates obtained with population-based metabolite correction (PBMC) and image-derived input function (IDIF) in comparison to arterial blood-based estimates, and compared repeatability. Eleven healthy volunteers underwent a [11C]AA scan; five repeated the scan 6 weeks later, simulating a pre- and post-treatment study design. For all scans, arterial blood was sampled to measure [11C]AA plasma radioactivity. Plasma [11C]AA parent fraction was measured in 5 scans. K* was quantified using both blood data and IDIF, corrected for [11C]AA parent fraction using both PBMC (from published values) and individually measured values (when available). K* repeatability was calculated in the test-retest subset. K* estimates based on blood and individual metabolites were highly correlated with estimates using PBMC with arterial input function ( r = 0.943) or IDIF ( r = 0.918) in the subset with measured metabolites. In the total dataset, using PBMC, IDIF-based estimates were moderately correlated with arterial input function-based estimates ( r = 0.712). PBMC and IDIF-based K* estimates were ∼6.4% to ∼11.9% higher, on average, than blood-based estimates. Average K* test-retest absolute percent difference values obtained using blood data or IDIF, assuming PBMC for both, were between 6.7% and 13.9%, comparable to other radiotracers. Our results support the possibility of simplified [11C]AA data acquisition through eliminating arterial blood sampling and metabolite analysis, while retaining comparable repeatability and validity. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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