## 5 Conclusions
The authors thank Philips Healthcare for providing tools for using an off-line attenuation map for PET reconstruction and technical assistance for implementing the TOF reconstruction protocol for brain image reconstruction. **Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results. \begin{table}
\begin{tabular}{r r r r r r r r r r r} \hline \multicolumn{1}{c}{} & \multicolumn{1}{c}{**2-Class MRAC (No Air)**} & \multicolumn{3}{c}{**2-Class MRAC**} & \multicolumn{3}{c}{**3-Class MRAC**} \\ \cline{2-13}  & **Non-TOF** & **TOF** & **DIFF** & **Non-TOF** & **TOF** & **DIFF** & **Non-TOF** & **TOF** & **DIFF** \\ \hline \multicolumn{1}{c}{} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} \\ \hline \multicolumn{1}{c}{} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1.5} & \multicolumn{1}{c}{1. * _[PERSON] et al. (2017)_ [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON] Clinical evaluation of TOF versus non-TOF on PET artifacts in simultaneous PET/MR: A dual centre experience. _Eur. J. Nucl. Med. Mol. Imaging_**2017**, _44_, 1223-1233. [CrossRef]
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