[11C]PiB is a derivative of a Thioflavin T histological dye for amyloid plaques (Klunk et al. 2003 (link)) that has good brain penetrance and specifically binds to fibrillar amyloid plaques. Up to 15 mCi of [11C]PiB (>2 mCi/nmol) was delivered intravenously via bolus injection (20-30s). PET data were acquired on Siemens ECAT HR+ scanners at both sites. A 6-10 min 68Ge/68Ga transmission scan was acquired for attenuation correction of annihilation radiation. PET data were reconstructed with a filtered back-projection algorithm (Direct Inverse Fourier Transform; DIFT) with sinogram trimming to a voxel size of 2.57 mm × 2.57 mm × 2.43 mm and matrix dimension of 128 × 128 × 63 with corrections for detector deadtime, scanner normalization, photon scatter, and radioactive decay.
PET scans were reoriented along the anterior commissure-posterior commissure (AC-PC) line, and inter-frame motion was corrected (AIR version 3.0; Woods et al. 1998 (link)). Standard uptake value ratio (SUVR) images were calculated from data 50-70 min post-injection (McNamee et al. 2009 (link)) with a cerebellar GM reference region drawn in native space (Klunk et al. 2004 (link); Lopresti et al. 2005 (link); Price et al. 2005 (link)).
PET scans were reoriented along the anterior commissure-posterior commissure (AC-PC) line, and inter-frame motion was corrected (AIR version 3.0; Woods et al. 1998 (link)). Standard uptake value ratio (SUVR) images were calculated from data 50-70 min post-injection (McNamee et al. 2009 (link)) with a cerebellar GM reference region drawn in native space (Klunk et al. 2004 (link); Lopresti et al. 2005 (link); Price et al. 2005 (link)).
