Proposal for a PET positron detector with scintillating fibers for the diagnosis of intestinal cancers

We propose a positron detector with 8 layers of scintillation fibers whose length is 1 m and whose diameter is 0.2 mm. The shape of this detector is like as endoscope but one layer of fibers is spirally rolled clockwise, and another layer is counter-clockwise. The pitch of inner and outer spiral fibers are 85 and 75mm, respectively. This detector can be installed into the intestines from the anus, and positrons emitted from PET agents can be directly measured. The azimuth angle and z-coordinate of incident positrons are determined from the 4 types of hit fibers. This inspection can be performed at the same time as the standard PET examination.