86 mm Volume Coil for MRI of Mice and Rats

Waiver Rationale Summary

The National Institute on Aging (NIA) requires an 86 mm volume coil capable of MRI scanning of large rats. This coil will serve as a spare for an identical unit that is critical to the performance of all rat and mouse experiments on NIA’s Biospec 94/20 MRI scanner. On both clinical and preclinical MRI scanners, most imaging is performed using a combination of a body coil, which surrounds the subject and transmits radio waves to excite nuclear spins, and a small surface coil or array, which receives the resulting radio-frequency signal from the area of interest, e.g. the brain. On the National Institute on Aging’s (NIA) STARRRS project’s Bruker Biospec 94/20 MRI scanner, the body coil is a 86 mm ID quadrature volume coil designed for both transmit-only and transmit-receive imaging and capable of accommodating rats up to about 1 kg in weight. This coil is absolutely essential for all brain imaging and most other applications. By purchasing a spare coil, NIA hopes to maintain this scanner in working order to collect data at critical time points on irreplaceable animals as part of the STARRRS project’s longitudinal neuroimaging component. Although there are U.S.-based manufacturers of coils for clinical and preclinical MRI scanners, none of these coils are compatible with NIA’s existing Bruker Biospec 94/20 MRI scanner. Procuring these would have no value to NIA’s program or to the Government since they simply could not function in this context.