Development of a MPPC-based prototype gantry for future MRI-PET scanners

作者：Kurei Y^*; Kataoka J; Kato T; Fujita T; Ohshima T; Taya T; Yamamoto S

来源：Journal of Instrumentation, 2014, 9(12): C12052.

DOI：10.1088/1748-0221/9/12/C12052

• Gamma camera, SPECT, PET PET/CT, coronary CT angiography (CTA)
• Photon detectors for UV, visible and IR photons (solid-state) (PIN diodes, APDs, Si-PMTs, G-APDs, CCDs, EBCCDs, EMCCDs etc)

We have developed a high spatial resolution, compact Positron Emission Tomography (PET) module designed for small animals and intended for use in magnetic resonance imaging (MRI) systems. This module consists of large-area, 4x4 ch MPPC arrays (S11830-3344MF; Hamamatsu Photonics K. K.) optically coupled with Ce-doped (Lu, Y)(2)(SiO4)O (Ce: LYSO) scintillators fabricated into 16 x 16 matrices of 0.5 x 0.5 mm(2) pixels. We set the temperature sensor (LM73CIMK-0; National Semiconductor Corp.) at the rear of the MPPC acceptance surface, and apply optimum voltage to maintain the gain. The eight MPPC-based PET modules and coincidence circuits were assembled into a gantry arranged in a ring 90 mmin diameter to form the MPPC-based PET system. We have developed two types PET gantry: one made of non-magnetic metal and the other made of acrylonitrile butadiene styrene (ABS) resins. The PET gantry was positioned around the RF coil of the 4.7 T MRI system. We took an image of a point Na-22 source under fast spin echo (FSE) and gradient echo (GE), in order to measure the interference between the MPPC-based PET and MRI. The spatial resolution of PET imaging in a transaxial plane of about 1 mm (FWHM) was achieved in all cases. Operating with PET made of ABS has no effect on MR images, while operating with PET made of non-magnetic metal has a significant detrimental effect on MR images. This paper describes our quantitative evaluations of PET images and MR images, and presents a more advanced version of the gantry for future MRI/DOI-PET systems.

• 出版日期2014-12