Active-PET: a multifunctional PET scanner with dynamic gantry size featuring high-resolution and high-sensitivity imaging: a Monte Carlo simulation study

Abstract

Organ-specific PET scanners have been developed to provide both high spatial resolution and sensitivity, although the deployment of several dedicated PET scanners at the same center is costly and space-consuming. Active-PET is a multifunctional PET scanner design exploiting the advantages of two different types of detectors modules and mechanical arms mechanism enabling to reposition the detectors to allow the implementation of different geometries/configurations. Active-PET can be used for different applications, including brain, axilla, breast, prostate, whole-body, preclinical and pediatrics imaging, cell tracking, and image guidance for therapy. Monte Carlo techniques were used to simulate a PET scanner with two sets of high resolution and high sensitivity pixelated Lutetium Oxyorthoscilicate (LSO(Ce)) detector blocks (24 for each group, overall 48 detector modules for each ring), one with large pixel size (4×4 mm2) and crystal thickness (20 mm), and another one with small pixel size (2×2 mm2) and thickness (10 mm). Each row of detector modules is connected to a linear motor that can displace the detectors forward and backward along the radial axis to achieve variable gantry diameter in order to image the target subject at the optimal/desired resolution and/or sensitivity. At the center of the field-of-view, the highest sensitivity (15.98 kcps/MBq) was achieved by the scanner with a small gantry and high-sensitivity detectors while the best spatial resolution was obtained by the scanner with a small gantry and high-resolution detectors (2.2 mm, 2.3 mm, 2.5 mm FWHM for tangential, radial, and axial, respectively). The configuration with large-bore (combination of high-resolution and high-sensitivity detectors) achieved better performance and provided higher image quality compared to the Biograph mCT as reflected by the 3D Hoffman brain phantom simulation study. We introduced the concept of a non-static PET scanner capable of switching between large and small field-of-view as well as high-resolution and high-sensitivity imaging.

A generative adversarial network to speed up optical Monte Carlo simulations

“…In addition to detector development, Monte Carlo simulations are widely used to simulate complete clinical and preclinical imaging systems (Ricci et al 2019, Ahmed et al 2020, Sarrut et al 2021a, Sanaat et al 2022, Zaidi and Andreo 2022. Detailed and complete system optical simulations of these systems, often composed of hundreds or thousands of scintillators, are computationally prohibitive and thus are always limited to the analysis of the first interaction gamma points to study the system performance (Gu et al 2015, Abbaszadeh et al 2018, Borghi et al 2018, Surti and Karp 2018.…”

Accurate modeling and performance evaluation of a total‐body pet scanner using Monte Carlo simulations

“…10,11 Monte Carlo simulations are widely used for modeling medical imaging devices, and can be employed to investigate the effects of different scanning parameters on the performance of different PET instrumentation designs and resulting image quality. [12][13][14][15][16][17] A number of simulation studies focused on total-body PET scanners.…”

Dose evaluation of the one-year-old child in PET imaging by 18F-(DOPA, FDG, FLT, FET) and 68Ga-EDTA using reference voxel phantoms

“…Sanaat et al conducted a study on a multipurpose PET system that is also useful for pediatric imaging. Active-PET is a multifunctional PET scanner design exploiting the advantages of two different types of detector modules and mechanical arms mechanisms enabling repositioning of the detectors to allow the implementation of different geometries/configurations [19]. In a study, Theruvath et al proposed the use of deep learning in low-dose (FDG) PET/MRI scans to assess correct treatment response in children and young adults with lymphoma [20].…”