Random Acquisition of Spectral Projections in Four-Dimensional Spectral-Spatial EPR Imaging: A Feasibility Study Toward Oxygen Imaging
摘要
In continuous-wave electron paramagnetic resonance (CW-EPR) imaging, many spectral projections are required to accurately reconstruct four-dimensional (4D) spectral-spatial data, which are used for oxygen mapping in tumors. The ability to obtain fewer spectral projections with less degradation of the resultant image quality is desirable because acquiring many spectral projections leads to a longer time for EPR imaging acquisition. The algebraic reconstruction technique (ART) is one of the most powerful image-reconstruction techniques for 4D spectral-spatial imaging. ART can be applied to incomplete sets of spectral projections. However, data sets of many spectral projections can provide reconstructed images of higher quality. In this study, we aimed to enhance acquisition speed by randomly collecting spectral projections and subsequently synthesizing those that had not been recorded. We applied this strategy to a numerical phantom and a mouse Hs766T xenograft model to confirm the feasibility of our concept. Random acquisition can prevent image degradation in linewidth mapping, which is the foundation for oxygen mapping with CW-EPR.