A block detector for a multislice, depth-of-interaction MR-compatible PET

We proposed and tested the a block detector for a multislice, depth-of-interaction (DOI) MR-compatible positron emission tomography (PET). The detector consists of a block detector, four optical fibers and photo-multiplier tubes (PMTs). The block detector is a lutetium oxyorthosilicate (LSO) DOI detector comprising eight LSOs arranged in a 2/spl times/2/spl times/2 matrix based on the concept proposed by Murayama et al. The size of a single scintillator of a prototype block detector was 2/spl times/2/spl times/2 mm. The scintillation photons are collected from the side of the scintillator block detector and are transferred to four channels of the position-sensitive PMT (PSPMT) using four optical fibers several meters long. The outputs of the PSPMT signals are calculated to determine the position of gamma interaction in the block detector. Results show that although the light loss from using the fiber was around 90%, there were sufficient transferred scintillation photons to obtain the photo-peak and to calculate the position of gamma interaction in the block detector with reasonable separation. We also modified the block detector to improve the performance of the detector. The size of a single scintillator of the modified block detector was enlarged to be 2.5 mm (transaxial) /spl times/ 3.5 mm (axial) /spl times/ 3.5 mm (depth) to improve the sensitivity. Good position responses as well as time resolution of 5.6-ns full-width at half-maximum (FWHM) were obtained for the modified block detector. With these results, we conclude that a two-rings, two-layer DOI-MR-compatible PET can be realized using the proposed block detector.

[1]  James F. Young,et al.  MicroPET: a high resolution PET scanner for imaging small animals , 1996, IEEE Nuclear Science Symposium Conference Record.

[2]  Z. Burbar,et al.  The ECAT HRRT: an example of NEMA scatter estimation issues for LSO based PET systems , 2003, 2003 IEEE Nuclear Science Symposium. Conference Record (IEEE Cat. No.03CH37515).

[3]  Simon R. Cherry,et al.  Design of a small animal MR compatible PET scanner , 1998, 1998 IEEE Nuclear Science Symposium Conference Record. 1998 IEEE Nuclear Science Symposium and Medical Imaging Conference (Cat. No.98CH36255).

[4]  E. Hoffman,et al.  Design considerations and initial performance of a 1.2 cm/sup 2/ beta imaging intra-operative probe , 1995 .

[5]  H. Murayama,et al.  Depth encoding multicrystal detectors for PET , 1998 .

[6]  C. A. Stover,et al.  Giant birefringent optics in multilayer polymer mirrors , 2000, Science.

[7]  S. Cherry,et al.  Simultaneous PET and MR imaging , 1997, Physics in medicine and biology.

[8]  Simon R. Cherry,et al.  Development of a PET detector system compatible with MRI/NMR systems , 1997 .

[9]  H. Murayama,et al.  A depth of interaction detector for PET with GSO crystals doped with different amount of Ce , 2001, 2001 IEEE Nuclear Science Symposium Conference Record (Cat. No.01CH37310).

[10]  Kagayaki Kuroda,et al.  Scintillator selection for MR compatible gamma detectors , 2002, 2002 IEEE Nuclear Science Symposium Conference Record.

[11]  Yiping Shao,et al.  PET and NMR dual acquisition (PANDA): applications to isolated, perfused rat hearts , 1997, NMR in biomedicine.

[12]  Hideo Murayama,et al.  A depth of interaction detector for PET with GSO crystals doped with different amounts of Ce , 2001 .