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A new multi-modality imaging tool is under development in the frameowrk of the INSERT (Integrated SPECT/MRI for Enhanced Stratification in Radio-chemo Therapy) project, supported by the European Community. The final goal is to develop a custom SPECT apparatus, that can be used as insert for commercially available MRI systems such as 3 T MRI with 59 com bore diameter. INSERT is expected to offer more effective and earlier diagnosis with potentially better outcome in survival for the treatment of brain tumors, primarily glioma. Two SPECT prototypes will be developed, on dedicated to predinical imaging, the second one dedicated to clinical imaging.

A new multi-modality imaging tool is under development in the framework of the INSERT (INtegrated SPECT/MRI for Enhanced Stratification in Radio-chemoTherapy) project, supported by the European Community. A custom SPECT apparatus, used as an insert for commercially available MRI systems, will enhance the treatment of brain tumors (primarily glioma) by offering more effective and earlier diagnosis with potentially better outcome in survival. The project aims to develop two SPECT prototypes, dedicated to preclinical and clinical imaging. The final goal is to fit the complete SPECT detection system into an existing MRI bore (diameter: 20 cm for the preclinical system and 59 cm for the clinical system). In this work, we propose the use of two possible photodetecors for the scintillator readout: Silicon Drift Detectors and Silicon PhotoMultipliers. A comparison between the main parameters of the two technologies as well as simulations about the achievable energy and spatial resolution are presented.

The paper presents an organic-based photodiode coupled to a CsI(Tl) scintillator to realize an X-ray detector. A suitable blend of an indolic squaraine derivative and of fullerene derivative has been used for the photodiode, thus allowing external quantum efficiency in excess of 10% at a wavelength of 570 nm, well matching the scintillator output spectrum. Thanks to the additional deposition of a 15 nm thin layer of a suitable low electron affinity polymer, carriers injection from the metal into the organic semiconductor has been suppressed, and dark current density as low as 1 nA/cm 2 has been obtained, which is comparable to standard Si-based photodiodes. By using a collimated X-ray beam impinging onto the scintillator mounted over the photodiode we have been able to measure current variations in the order of 150 pA on a dark current floor of less than 50 pA when operating the X-ray tube in switching mode, thus proving the feasibility of indirect X-ray detection by means of organic semiconductors. © 2012 IEEE.