A detector for radionuclide bronchial scanning

This paper aims to describe a sub-miniature scintillation detector suitable for functional bronchial scanning and solitary pulmonary nodules detection. The device is made by a probe having diameter adequate for insertion in a catheter and external electronics for signalʹs analysis. The final scanner will be composed of a train of individual detectors, each one made by a scintillation crystal and a Si-avalanche photodiode operating in single-photon modality. The setup shows high-efficiency photon detection and high quantum-efficiency readout giving adequate energy resolution for efficient rejection of scattered events. The crystal can be adequately shielded to reduce the background from healthy tissues. Assuming the use of a radiopharmaceutical labeled with 99mTc, Monte Carlo simulations concerning a simple pulmonary model have been performed at 57Co lines and compared to experimental results. Furthermore, useful simulated data have been obtained at 140 keV concerning the strategy for background reduction to improve nodule localization.