Optimized image acquisition for dopamine transporter imaging with ultra-high resolution clinical pinhole SPECT

Optimized image acquisition for dopamine transporter imaging with ultra-high resolution clinical pinhole SPECT

Chen, Y. (TU Delft RST/Biomedical Imaging)
Vastenhouw, B. (MILabs B.V.; University Medical Center Utrecht)
Wu, C. (TU Delft RST/Biomedical Imaging; MILabs B.V.; University Medical Center Utrecht)
Goorden, M.C. (TU Delft RST/Biomedical Imaging)
Beekman, F.J. (TU Delft RST/Biomedical Imaging; MILabs B.V.; University Medical Center Utrecht)

2018

SPECT can be used to image dopamine transporter (DaT) availability in the human striatum, e.g. for diagnosis of Parkinson's disease (PD). As traditional SPECT provides limited resolution and sensitivity, we proposed a full ring focusing multi-pinhole SPECT system (G-SPECT-I (Beekman 2015 Eur. J. Nucl. Med. Mol. Imaging 42 S209)) which demonstrated a 2.5 mm reconstructed resolution in phantom scans. G-SPECT-I achieves data completeness in the scan region of interest by translating the patient bed with an xyz-stage and combining projections from all bed positions into image reconstruction using a scanning focus method (SFM). This paper aims to develop dedicated SFM parameters for performing a DaTscan with high effective sensitivity and appropriate sampling. To this end, the axial scanning length was restricted and transaxial bed trajectories with a reduced number of positions based on a convex hull data-completeness model were tested. Quantitative accuracy was assessed using full G-SPECT-I simulations of an Alderson phantom based on measured system matrices. For each sampling strategy, the specific binding ratio (SBR) and asymmetry index (AI) in the left and right striatum, as well as the Localized SBR (L-SBR) and the Localized AI (L-AI) in eight striatal sub-regions were calculated and compared to those of the reference scan which performs full brain oversampling using 112 bed positions. Results show that structures essential for PD diagnosis were visually and quantitatively barely affected even when using the lowest number of bed translations (i.e. 4). The maximum deviation from the reference was only 1.5%, 1.5%, 5.5% and 7.0% for the SBR, AI, L-SBR and L-AI, respectively, when 4 positions were used. Thus, it is possible to perform an accurate DaTscan with a confined axial scan region and a limited number of focused bed positions. This enables protocols for extremely fast dynamic SPECT scans with less than half-minute time frames, which can be useful for motion correction.

http://resolver.tudelft.nl/uuid:62dceec8-6370-406a-a70f-b7f0aa0f1067

https://doi.org/10.1088/1361-6560/aae76c

2018-11-07

0031-9155

Physics in Medicine and Biology, 63 (22)

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

journal article

© 2018 Y. Chen, B. Vastenhouw, C. Wu, M.C. Goorden, F.J. Beekman