PT - JOURNAL ARTICLE AU - Young Sub Lee AU - Jin Su Kim AU - Kyeong Min Kim AU - A Ram Yu AU - Jong Guk Kim AU - JiAe Park AU - Wonho Lee AU - Sang-Keun Woo AU - Hee-Joung Kim AU - Gi Jeong Cheon TI - Assessment of 3D PET reconstruction with system matrix using point source measurement on Siemens Biograph True Point PET/CT DP - 2010 May 01 TA - Journal of Nuclear Medicine PG - 1373--1373 VI - 51 IP - supplement 2 4099 - http://jnm.snmjournals.org/content/51/supplement_2/1373.short 4100 - http://jnm.snmjournals.org/content/51/supplement_2/1373.full SO - J Nucl Med2010 May 01; 51 AB - 1373 Objectives PET resolution was dramatically improved as crystal and geometrical efficiency were corrected using measured point spread functions in iterative reconstruction algorithms. In this study, we investigated the improvement of resolution and lesion detectability for Siemens biograph true point PET scanner. Methods For the resolution measurement, F-18 point source was placed at the center of the axial and transaxial FOV. After acquiring data at the center of FOV, the point source was moved in the vertical steps of 4 cm from 0 to 20 cm. For image quality measurement, IEC body phantom was used. PET scan was performed using both brain mode (pixel size: 1.34 x 1.34 mm2) and whole body (WB) mode (pixel size: 4.07 x 4.07 mm2). PET data was reconstructed using 3D PET reconstruction with system matrix derived from point source measuement (True X option in Siemens PET) and conventional iterative reconstruction (OSEM, subset:4, iteration:16). Results Spatial resolution was 2.0 (TrueX) and 4.1 mm (without TrueX) at center of the FOV, and 2.4 (TrueX) and 7.0 mm (without TrueX) at 20 cm offset from the center. In WB mode, %contrast was 14, 34, 57, and 77% for 10, 13, 17, 22 mm hot spheres and 79% and 78% for 28 and 37 mm cold spheres using TrueX option. %contrast without trueX option was 12, 16, 37, 55, 70, and 70%, respectively. Background variability was approximately 15% with TrueX, and was less than 5% without TrueX. In brain mode, %contrast was approximately 93% (TrueX) and 86% (without TrueX). Conclusions The results suggest that resolution and %contrast were improved using 3D PET reconstruction with system matrix derived from point source measurment. However, with TrueX option, optimal scan time should be considered for maintaining the consistency of equivalent background variability to enhance the lesion detectability in the oncology PET studies