Abstract
Surface coil resonators have been widely used to perform topical EPR spectroscopy. They are usually positioned adjacent to or implanted within the body. For EPR applications these resonators have a number of important advantages over other resonator designs due to their ease of sample accessibility, mechanical fabrication, implementation of electronic tuning and coupling functions, and low susceptibility to sample motions. However, a disadvantage is their B1 field inhomogeneity, which limits their usefulness for 3D imaging applications. We show that this problem can be addressed by mapping and correcting the B1 field distribution. We report the use of EPR imaging (EPRI) to map the B1 distribution of a surface coil resonator. We show that EPRI provides a fast, accurate, and reliable technique to evaluate the B1 distribution. 3D EPRI was performed on phantoms, prepared using three different saline concentrations, to obtain the B1 distribution. The information obtained from the phantoms was used to correct the images of living animals. With the use of this B1 correction technique, surface coil resonators can be applied to perform 3D mapping of the distribution of free radicals in biological samples and living systems.
Original language | English (US) |
---|---|
Pages (from-to) | 1057-1062 |
Number of pages | 6 |
Journal | Magnetic Resonance in Medicine |
Volume | 48 |
Issue number | 6 |
DOIs | |
State | Published - Dec 1 2002 |
Externally published | Yes |
Keywords
- B correction
- B mapping
- EPR imaging
- Free radicals
- MRI
- Nitroxides
- Saline
- Surface coil resonator
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging
- Radiological and Ultrasound Technology