%0 Journal Article %A In Suk Kwak %A Han-Gyu Kang %A Jeong-Whan Son %A Jae Sung Lee %A Seong Jong Hong %T A feasibility study of an intraoperative beta imaging/gamma probe using a depth of interaction measurement %D 2015 %J Journal of Nuclear Medicine %P 1867-1867 %V 56 %N supplement 3 %X 1867 Objectives An intraoperative beta imaging/gamma probe using a depth of interaction measurement.Methods The proposed beta/imaging/gamma probe consisted of a 4×1 array of plastic scintillator (2.9×2.0×12 mm3), a monolithic GAGG crystal (9×12×12 mm3), and a SiPM (Hamamatsu, S11828-3344M) with 4×4 array channels which of each has an effective area of 3×3 mm2. The plastic scintillator array was optically coupled to the 4×1 channels of the SiPM and the outer surfaces of the plastic scintillators were wrapped with an enhanced specular reflector (ESR) except the three 2.0×12 mm2 interfaces of inter-plastic scintillators. The monolithic GAGG crystal wrapped with Teflon tape was optically coupled to the 4×3 channels of the SiPM. Various ESR reflectors such as a 0.3 mm uniform holes reflector, a gradient hole sized reflector, and a gradient rectangular cutout reflector were inserted into the inter-plastic scintillators interfaces and the air gaps of the holes were filled with optical grease with an index of refraction of 1.46. The laser machining technique was used to manufacture the various ESR reflectors to be used for light spreading between the plastic scintillators. An F-18 (1 MBq) point source was irradiated along the plastic scintillators with a 3 mm step, and QDC and DOI ratios were measured.Results The beta and gamma signal can be obtained separately with individual SiPM channels. The gradient rectangular cutout reflector showed the best average DOI resolution of 4.38±1.6 mm.Conclusions The beta/gamma signals were processed with different SiPM channels, henceforth a pulse shaping method was not required to discriminate the beta from the gamma signals. The DOI resolution could be improved using a light sharing reflector between plastic scintillators. %U