3-D Reconstruction Benchmark of a Compton Camera Against a Parallel-Hole Gamma Camera on Ideal Data

Abstract

Compton cameras and collimated gamma cameras are competing devices suitable for prompt gamma detection in range verification of particle therapy. In this study, we evaluate the first approach from the point of view of the tomographic reconstruction step by comparing it to the second. We clear any technological constraints by considering a simple geometry, ideal detecting stages, a mono-energetic synthetic phantom. To this end, both analytic (filtered backprojection) and iterative (maximum likelihood expectation maximization) algorithms are applied in conjunction with total variation denoising. The results we obtain show that the collimated configuration leads to slightly better images when the same number of acquired events is used for the reconstruction. However, the Compton camera might equal the collimator-based camera if we take into account the superior efficiency and might surpass it in a limited angle configuration when the collimated camera cannot span the entire angular range.

The conical Radon transform with vertices on triple line segments

“…Remark 5 (Generalization to different vertex sets). We point out that an inversion formula similar to (7) can also be derived for other arrangements triple line detectors. In such a case, one reconstructs a function f ∈ C ∞ (R 3 ) with compact support in a certain set K depending on Ξ by deriving generalizations of Lemma 3 and Theorem 4.…”

“…[4-6, 10, 16, 19, 22]). On the other hand, Compton camera data are considerably noisy and utilizing full five-dimensional data is advised to obtain accurate reconstruction results [1,7]. However, the data of planar sensors can be grouped in data sets of several virtual linear detectors.…”

“…[4-6, 10, 19, 23, 26]). On the other hand, due to the random emission of gamma-rays, Compton camera data are considerably noisy and utilizing full five-dimensional data is advised to obtain accurate reconstruction results [1,7]. In pure form, a one-dimensional Compton camera suffers from a low SNR.…”

Advanced Monte Carlo simulations of emission tomography imaging systems with GATE

“…The PRESTO toolkit (PET Reconstruction Software Toolkit) (Scheins and Herzog 2008, Scheins et al 2011, 2015 can also be used with GATE output, such as in Xu et al (2019). Finally, several Compton Camera reconstruction approaches have been used with GATE data, such as in Muñoz et al (2018), Kohlhase et al (2020) (MLEM or Origin Ensemble) or in Feng et al (2020), Maxim (2019) (with conical Radon transform modeling).…”