PT  - JOURNAL ARTICLE
AU  - Chi Liu
AU  - Jingyan Xu
AU  - Benjamin Tsui
TI  - Projector implementation for improved rotating multi-segment variable-angle slant-hole SPECT reconstruction
DP  - 2008 May 01
TA  - Journal of Nuclear Medicine
PG  - 399P--399P
VI  - 49
IP  - supplement 1
4099  - http://jnm.snmjournals.org/content/49/supplement_1/399P.3.short
4100  - http://jnm.snmjournals.org/content/49/supplement_1/399P.3.full
SO  - J Nucl Med2008 May 01; 49
AB  - 1682 Objectives: In this work we develop a new projector implementation for rotating multi-segment variable-angle slant-hole (RMVASH) SPECT reconstruction that correctly takes into account all the voxels contributing to a given projection bin and evaluate the potential reconstruction improvement. Methods: Differ from the conventional method that uses two-voxel bilinear interpolation leading to an incomplete projection estimation due to the diverging fan-beam geometry in each segment of the RMVASH collimator, the proposed implementation first determines the contributing image voxels to a given bin at each distance according to the collimator geometry. The value of each projection bin was then estimated by summing the contributions of all the image voxels that project to it. To evaluate the proposed method, we compared the profiles through the projections of a point source generated by using the conventional and the proposed implementations. We also simulated a small hot spot in a uniform sphere and reconstructed the simulated projections using both implementations. The reconstructed image quality was evaluated in terms of the full-width-at-half-maximum (FWHM) and the contrast of the hot spot. Results: The profile of the point source projection generated by using the proposed is wider than that of the conventional projector and is consistent with those from the Monte Carlo simulation. By comparing the reconstructed images of the hot spot in the sphere, we found the proposed implementation gave smaller FWHM and higher contrast than those from the conventional implementation. Conclusions: The proposed projector implementation in RMVASH SPECT reconstruction leads to more accurate projection data estimation and results in reconstructed images with better resolution and higher contrast as compared with the conventional implementation. Research Support: NIH R01-EB001983