by de Alejo, Rigoberto Pérez, Garrido, Carlos, Villa, Palmira, Rodriguez, Ignacio, Vaquero, Juan José, Ruiz-Cabello, Jesus and Cortijo, Manuel
Abstract:
A new circuit design for automatically tuning and matching a saddle coil for small animal imaging is presented. This design allows working at (1)H, (19)F, and (3)He resonance frequencies in a 4.7 T spectrometer. It is based on a balanced circuit with commercial variable capacity diodes controlled by a computer using digital potentiometers. The change between two different frequencies can be accurately performed in a few seconds. System Q is compared, between 140-210 MHz, to the same coil tuned and matched with high Q variable capacitors. Differences lower than 5% were found with a loaded coil. The proposed design has initially been evaluated in (19)F and (1)H NMR images acquired with a five-tube phantom. An application is also shown for the acquisition of (3)He, (19)F, and (1)H lung images in a control rat.
Reference:
Automatic tuning and matching of a small multifrequency saddle coil at 4.7 T. (de Alejo, Rigoberto Pérez, Garrido, Carlos, Villa, Palmira, Rodriguez, Ignacio, Vaquero, Juan José, Ruiz-Cabello, Jesus and Cortijo, Manuel), In Magnetic Resonance in Medicine, volume 51, 2004.
Bibtex Entry:
@article{de_alejo_automatic_2004,
	title = {Automatic tuning and matching of a small multifrequency saddle coil at 4.7 {T}.},
	volume = {51},
	url = {http://doi.wiley.com/10.1002/mrm.20045},
	doi = {10.1002/mrm.20045},
	abstract = {A new circuit design for automatically tuning and matching a saddle coil for small animal imaging is presented. This design allows working at (1)H, (19)F, and (3)He resonance frequencies in a 4.7 T spectrometer. It is based on a balanced circuit with commercial variable capacity diodes controlled by a computer using digital potentiometers. The change between two different frequencies can be accurately performed in a few seconds. System Q is compared, between 140-210 MHz, to the same coil tuned and matched with high Q variable capacitors. Differences lower than 5% were found with a loaded coil. The proposed design has initially been evaluated in (19)F and (1)H NMR images acquired with a five-tube phantom. An application is also shown for the acquisition of (3)He, (19)F, and (1)H lung images in a control rat.},
	language = {English},
	number = {4},
	journal = {Magnetic Resonance in Medicine},
	author = {de Alejo, Rigoberto Pérez and Garrido, Carlos and Villa, Palmira and Rodriguez, Ignacio and Vaquero, Juan José and Ruiz-Cabello, Jesus and Cortijo, Manuel},
	month = apr,
	year = {2004},
	pmid = {15065264},
	note = {Publisher: Wiley Subscription Services, Inc., A Wiley Company},
	pages = {869--873}
}