Tailored sinc pulses for uniform excitation and artifact-free radio frequency time-domain EPR imaging

N Devasahayam; R Murugesan; K Matsumoto; J B Mitchell; J A Cook; S Subramanian; M C Krishna

doi:10.1016/j.jmr.2004.01.016

Tailored sinc pulses for uniform excitation and artifact-free radio frequency time-domain EPR imaging

J Magn Reson. 2004 May;168(1):110-7. doi: 10.1016/j.jmr.2004.01.016.

Authors

N Devasahayam¹, R Murugesan, K Matsumoto, J B Mitchell, J A Cook, S Subramanian, M C Krishna

Affiliation

¹ Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.

PMID: 15082255
DOI: 10.1016/j.jmr.2004.01.016

Abstract

A method to generate shaped radiofrequency pulses for uniform excitation of electron spins in time-domain radio frequency (RF) electron paramagnetic resonance (EPR) imaging is presented. A commercial waveform generator was integrated with the transmit arm of the existing time-domain RF-EPR spectrometer to generate tailored excitation pulses with sub-nano second resolution for excitation with a 90 degrees flip-angle. A truncated sinc [sin(x)/x] pulse, tailored to compensate for the Q-profile (RF frequency response) of the resonator, was shown to yield images from phantom objects as well as in vivo images, with minimal distortion. These studies point to the advantages in using shaped sinc pulses to achieve improved uniform excitation over a relatively wide bandwidth region in time-domain RF-EPR imaging (RF-FT-EPRI).

MeSH terms

Animals
Artifacts
Diagnostic Imaging / methods*
Electron Spin Resonance Spectroscopy / instrumentation*
Electron Spin Resonance Spectroscopy / methods*
Equipment Design
Image Enhancement / methods*
Mice
Mice, Inbred C3H
Phantoms, Imaging