NIRS NEWS No.106, SEP 2005

Young Investigators Award
in the 52nd Annual Meeting of the Society of Nuclear Medicine (SNM)

Dr. Eiji Yoshida

Dr. Yoshida was awarded the Young Investigators Award in the 52nd Annual Meeting of the Society of Nuclear Medicine (SNM). His oral presentation entitled "Transaxial Resolution Uniformity of the jPET-D4 with a Robust DOI Detector Calibration" introduced recent development of the jPET-D4 from the point of the uniform spatial resolution of ca. 3mm over the whole field of view.

The intensity of the signal depends on the scintillation properties of each crystal, the sensitivity and multiplication rate of each detector, and the depth of interaction (DOI) of each event. He has developed statistical calibration method to obtain uniform energy and spatial resolution from the 120,000 crystals, and proved that both the spacial resolution and the sensitivity can be improved at the same time by using the four-layer DOI detector.

This achievement will be applied to regional PET scanners such as a mammography or a small one for animals used in the field of molecular imaging.

The energy resolution was improved from 40% to 18% by the statistical calibration method.