@inproceedings{10764fd8fd804242b81d9ee19bb6bee0,
title = "Verification of a hybrid adjoint methodology in TITAN for single photon emission computed tomography",
abstract = "The hybrid deterministic transport code TITAN is being applied to a Single Photon Emission Computed Tomography (SPECT) simulation of a myocardial perfusion study. The TITAN code's hybrid methodology allows the use of a discrete ordinates solver in the phantom region and a characteristics method solver in the collimator region. Currently we seek to validate the adjoint methodology in TITAN for this application using a SPECT model that has been created in the MCNP5 Monte Carlo code. The TITAN methodology was examined based on the response of a single voxel detector placed in front of the heart with and without collimation. For the case without collimation, the TITAN response for single voxel-sized detector had a -9.96% difference relative to the MCNP5 response. To simulate collimation, the adjoint source was specified in directions located within the collimator acceptance angle. For a single collimator hole with a diameter matching the voxel dimension, a difference of -0.22% was observed. Comparisons to groupings of smaller collimator holes of two different sizes resulted in relative differences of 0.60% and 0.12%. The number of adjoint source directions within an acceptance angle was increased and showed no significant change in accuracy. Our results indicate that the hybrid adjoint methodology of TITAN yields accurate solutions greater than a factor of two faster than MCNP5.",
keywords = "Adjoint, Deterministic, Monte Carlo, SPECT",
author = "Katherine Royston and Alireza Haghighat and Ce Yi",
year = "2010",
language = "English",
isbn = "9781617820014",
series = "International Conference on the Physics of Reactors 2010, PHYSOR 2010",
publisher = "American Nuclear Society",
pages = "3462--3474",
booktitle = "International Conference on the Physics of Reactors 2010, PHYSOR 2010",
note = "International Conference on the Physics of Reactors 2010, PHYSOR 2010 ; Conference date: 09-05-2010 Through 14-05-2010",
}