Title
A dual RF resonator system for high-field functional magnetic resonance imaging of small animals
UMMS Affiliation
Department of Psychiatry
Publication Date
2004-01-07
Document Type
Article
Subjects
Animals; Brain; Brain Mapping; Electromagnetic Fields; Electronics; Electrophysiology; Magnetic Resonance Imaging; Magnetics; Neurophysiology; Rats; Reproducibility of Results; Restraint, Physical; Sensitivity and Specificity
Disciplines
Psychiatry
Abstract
A new apparatus has been developed that integrates an animal restrainer arrangement for small animals with an actively tunable/detunable dual radio-frequency (RF) coil system for in vivo anatomical and functional magnetic resonance imaging of small animals at 4.7 T. The radio-frequency coil features an eight-element microstrip line configuration that, in conjunction with a segmented outer copper shield, forms a transversal electromagnetic (TEM) resonator structure. Matching and active tuning/detuning is achieved through fixed/variable capacitors and a PIN diode for each resonator element. These components along with radio-frequency chokes (RFCs) and blocking capacitors are placed on two printed circuit boards (PCBs) whose copper coated ground planes form the front and back of the volume coil and are therefore an integral part of the resonator structure. The magnetic resonance signal response is received with a dome-shaped single-loop surface coil that can be height-adjustable with respect to the animal's head. The conscious animal is immobilized through a mechanical arrangement that consists of a Plexiglas body tube and a head restrainer. This restrainer has a cylindrical holder with a mouthpiece and position screws to receive and restrain the head of the animal. The apparatus is intended to perform anatomical and functional magnetic resonance imaging in conscious animals such as mice, rats, hamsters, and marmosets. Cranial images acquired from fully conscious rats in a 4.7 T Bruker 40 cm bore animal scanner underscore the feasibility of this approach and bode well to extend this system to the imaging of other animals.
Source
J Neurosci Methods. 2004 Jan 30;132(2):125-35.
Journal/Book/Conference Title
Journal of neuroscience methods
Related Resources
PubMed ID
14706710
Repository Citation
Ludwig R, Bodgdanov G, King JA, Allard A, Ferris CF. (2004). A dual RF resonator system for high-field functional magnetic resonance imaging of small animals. Psychiatry Publications and Presentations. Retrieved from https://escholarship.umassmed.edu/psych_pp/350