Estimation of mean and median pO2 values for a composite EPR spectrum.
Electron paramagnetic resonance (EPR)-based oximetry is capable of quantifying oxygen content in samples. However, for a heterogeneous environment with multiple pO2 values, peak-to-peak linewidth of the composite EPR lineshape does not provide a reliable estimate of the overall pO2 in the sample. The estimate, depending on the heterogeneity, can be severely biased towards narrow components. To address this issue, we suggest a postprocessing method to recover the linewidth histogram which can be used in estimating meaningful parameters, such as the mean and median pO2 values. This information, although not as comprehensive as obtained by EPR spectral-spatial imaging, goes beyond what can be generally achieved with conventional EPR spectroscopy. Substantially shorter acquisition times, in comparison to EPR imaging, may prompt its use in clinically relevant models. For validation, simulation and EPR experiment data are presented.
Ahmad
Rizwan
R
Center for Biomedical EPR Spectroscopy and Imaging, Davis Heart and Lung Research Institute, Department of Internal Medicine, The Ohio State University, 420 West 12th Avenue, TMRF-114, Columbus, OH 43210, USA.
Vikram
Deepti S
DS
Potter
Lee C
LC
Kuppusamy
Periannan
P
D003198:Computer Simulation; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D004867:Equipment Design; D010092:Oximetry / Q000379:methods*; D019047:Phantoms, Imaging; D011166:Porphyrins / Q000737:chemistry
D011166:Porphyrins; C487013:lithium octa-n-butoxynaphthalocyanine