Optimisation of PET data processing for a single injection experiment with [11C]Raclopride using a simulations based approach

Objectives Positron emission tomography (PET) with [11C]Raclopride is an important tool for studying dopamine D2 receptor expression in vivo. [11C]Raclopride PET binding experiments conducted using the Partial Saturation Approach (PSA) (a simple, single injection experiment, Delforge 1995) allow the estimation of receptor density (Bavail) and the in vivo affinity 1/(KD). To achieve accurate and stable parameter estimates, and the ability to detect small changes in these parameters, the impact of the data processing chain should be investigated and optimised. Methods Two groups of PET scans were generated for a Partial Saturation Approach (PSA) experiment using Monte Carlo simulation software with a biological phenomenon inferred between the groups. The kinetic parameters Bavail and KD were estimated and the impact of spatial smoothing, temporal denoising and image resolution recovery on the statistical detectability of change in the estimates was investigated. Results Before optimisation, the inferred Bavail difference between the two groups was underestimated by 42% and detected in 66% of cases (at p<0.05), while a false decrease of KD by 13% was detected in more than 11% of cases. After optimisation, the calculated Bavail difference was underestimated by only 3.7% and detected in 89% of cases, while a false slight increase of KD by 3.7 % was detected in only 2% of cases. Conclusions The use of Monte Carlo generated PET scans allowed the optimisation of the data processing chain in order to reliably estimate and detect changes in the parameters Bavail and KD.

Keywords

Positron computed tomography, Data processing, Injection, Simulation, Dopamine, Receptors, Monte Carlo Method

Citation

Wimberley, C., Angelis, G., Boisson, F., Callaghan, P., Fischer, K., Pichler, B., Meikle, S., Gregoire, M. C., & Reilhac, A. (2014). Optimisation of PET data processing for a single injection experiment with [11C]Raclopride using a simulations based approach. Journal of Nuclear Medicine, 55 (Supplement 1), 2019. https://jnm.snmjournals.org/content/55/supplement_1/2019/tab-article-info