Design study of dedicated brain PET with polyhedron geometry

Abstract

Abstract. BACKGROUND: Despite being the conventional choice, whole body PET cameras with a 76 cm diameter ring are not the optimal means of human brain imaging. OBJECTIVE: In fact, a dedicated brain PET with a better geometrical structure has the potential to achieve a higher sensitivity, a higher signal-to-noise ratio, and a better imaging performance. METHODS: In this study, a polyhedron geometrical dedicated brain PET (a dodecahedron design) is compared to three other candidates via their geometrical efficiencies by calculating the Solid Angle Fractions (SAF); the three other candidates include a spherical cap design, a cylindrical design, and the conventional whole body PET. RESULTS: The spherical cap and the dodecahedron have an identical SAF that is 58.4% higher than that of a 30 cm diameter cylinder and 5.44 times higher than that of a 76 cm diameter cylinder. The conceptual polygon-shape detectors (including pentagon and hexagon detectors based on the PMT-light-sharing scheme instead of the conventional square-shaped block detector module) are presented for the polyhedron PET design. Monte Carlo simulations are performed in order to validate the detector decoding. CONCLUSIONS:The results show that crystals in a pentagon-shape detector can be successfully decoded by Anger Logic. The new detector designs support the polyhedron PET investigation.

Design and modeling of a high resolution and high sensitivity PET brain scanner with double-ended readout

“…where Rect(F) is a rectangular profile with width F and Gauss(F) is a Gaussian profile with FWHM F. The positron range produces a non-Gaussian blurring, but for 18 F-labeled tracers imaged with this kind of scanner, its contribution to the final resolution is very small, and a rough Gaussian approximation (0.6 mm FWHM) is used here. We report the radial and tangential spatial resolutions from the center of the field of view to a 15 cm radial offset from the center of the field of view using equation (5).…”

“…This scanner was shown via simulation to reach a sensitivity of 23% in the brain region and a CTR of better than 150 ps. Other designs focused on high sensitivity and tight enclosure include the compact, multi-layer design of Gong et al [14]; the wearable HelmetPET proposed by Majewski et al [15]; the spherical brain PET scanner proposed for compatibility with 7T MRI by Catana [16]; the tight, asymmetric cylinder brain PET scanner proposed by Wang et al [17]; and the polyhedral brain PET scanners proposed by Shi et al [18] and Tao et al [19].…”

Development of Dedicated Brain PET Imaging Devices: Recent Advances and Future Perspectives

“…Shi et al investigated several polyhedron geometries and concluded that the dodecahedron design provides the same solid-angle coverage as a spherical cap, both substantially higher than that of a 30-cmdiameter cylindrical scanner. They also claimed that the dodecahedral geometry provides the best tradeoff between solid-angle coverage and reasonable complexity to allow manufacturing and even proposed a light-sharing scheme for reading out the pentagon-shaped detectors using photomultiplier tubes (34). Subsequently, they performed careful Monte Carlo simulations for the dodecahedral geometry (Fig.…”

Proposal for a PET scanner with 4π formula steradian span

“…[86] The idea of using this kind of geometry on a radiation detector has already been considered by other groups. On [87] the authors propose a brain PET design based on a dodecahedron. On [88] the authors propose a coded spherical configuration, with 4 isotropic field of view that can be used for coded aperture and Compton imaging.…”