Publications by authors named "L Theodorakis"

We aim to investigate the counting response variations of positron emission tomography (PET) scanners with different detector configurations in the presence of solitary pulmonary nodule (SPN). Using experimentally validated Monte Carlo simulations, the counting performance of four different scanner models with varying tumor activity, location, and patient obesity is represented using a noise equivalent count rate (NECR). NECR is a well-established quantitative metric which has positive correlation with clinically perceived image quality.

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Background: Lutetium-based scintillators with high-performance electronics introduced time-of-flight (TOF) reconstruction in the clinical setting. Let G' be the total signal to noise ratio gain in a reconstructed image using the TOF kernel compared with conventional reconstruction modes. G' is then the product of G1 gain arising from the reconstruction process itself and (n-1) other gain factors (G2, G3, … Gn) arising from the inherent properties of the detector.

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The advent of PET instrumentation signaled the beginning of a new perspective in nuclear medicine diagnostic imaging. PET systems rely on several corrections that must be applied in order to establish accurate and reliable quantification. The inherent properties of PET detector architecture and the crystals themselves are sources of different types of systematic and random errors with subsequent count rate variability that should be accounted for.

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