TY - JOUR T1 - Quantitative characteristics of maximum a posteriori reconstruction on binding potential measurements of <sup>11</sup>C-Flumazenil in small-animal brain PET JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 2067 LP - 2067 VL - 52 IS - supplement 1 AU - Keiichi Magota AU - Naoki Kubo AU - Songji Zhao AU - Yuji Kuge AU - Kenji Hirata AU - Naoya Hattori AU - Tohru Shiga AU - Chietsugu Katoh AU - Nagara Tamaki Y1 - 2011/05/01 UR - http://jnm.snmjournals.org/content/52/supplement_1/2067.abstract N2 - 2067 Objectives The purpose of this study was to investigate the image characteristics and effects of maximum a posteriori (MAP) reconstruction on the binding potential (BP) measurements of 11C-Flumazenil (FMZ) in small-animal brain PET compared with filtered back-projection (FBP). Methods Data were acquired on an Inveon (Siemens), and were reconstructed using MAP (subsets, 16; iterations, 2; MAP iterations, 18; β, 0.5) and FBP. To compare between MAP vs. FBP, a spatial resolution and image noise were evaluated. A cylindrical phantom filled with an 11C, which was scanned in a list mode for 6 h. For the BP measurements in animal, eight rats (208 ± 27 g) were scanned after injection of FMZ (70 ± 29 MBq). The BP with a simplified reference tissue model and its interobserver variability were compared between MAP vs. FBP. Results The spatial resolution at the center were almost same (MAP, 1.3 mm; FBP, 1.6 mm full-width at half-maximum). For the range of activity from 3.31 to 543 MBq/mL, the coefficient of variation for MAP (8.4% - 1.2%) was less than that for FBP (91.0% - 10.2%), indicating lower statistical noise in MAP than in FBP. In addition, the interobserver variability was smaller in MAP (r = 0.67, p = 0.08) than in FBP (r = 0.29, p = 0.50). The BP values using MAP (0.92 ± 0.21) were significantly lower than FBP (1.15 ± 0.26, p &lt; 0.05). Conclusions MAP reduced statistical noise and provided higher reproducibility on reference tissue model than the conventional FBP reconstruction. However, it also affected the quantitative estimation of the BP. Further research shall warrant the use of MAP for the BP measurements ER -