Electron paramagnetic resonance (EPR) Imaging (EPRI) is a robust method for measuring
in vivo oxygen concentration (pO2). For 3D pulse EPRI, a
commonly used reconstruction algorithm is the filtered backprojection (FBP) algorithm, in
which the backprojection process is computationally intensive and may be time consuming
when implemented on a CPU. A multistage implementation of the backprojection can be used
for acceleration, however it is not flexible (requires equal linear angle projection
distribution) and may still be time consuming. In this work, single-stage backprojection
is implemented on a GPU (Graphics Processing Units) having 1152 cores to accelerate the
process. The GPU implementation results in acceleration by over a factor of 200 overall
and by over a factor of 3500 if only the computing time is considered. Some important
experiences regarding the implementation of GPU-accelerated backprojection for EPRI are
summarized. The resulting accelerated image reconstruction is useful for real-time image
reconstruction monitoring and other time sensitive applications.
