The F.M. Kirby Research Center for Functional Brain Imaging occupies over five thousand square feet of space at the ground level of Baltimore's Kennedy Krieger Institute. The Center's primary resources are a pair of Philips MRI scanners, one at 1.5 Tesla and one at 3.0 Tesla.  These scanners have several unique features. Both scanners haveshort bores, namely 60 cm (with 60 cm diameter), which flares out to the front and back of the magnet (total magnet length, cover-to-cover, is only 179 cm).  This short bore provides a comfortable scanning environment, especially valuable for studies in children, the elderly, and subjects with neurological and psychiatric disorders. Despite this shorter bore, the magnet still has excellent field homogeneity and performs all modern imaging technologies, including fast imaging techniques such as echo-planar (EPI), fast spin echo, and parallel image acquisition (SENSE). Other methods available are diffusion imaging with EPI and navigator echoes, single-voxel MR spectroscopy (MRS) and multi-slice spectroscopic imaging (MRSI) approaches.

Both scanners have a second radio-frequency channel which allows heteronuclear and homonuclear MR spectroscopy with decoupling interleaved with fast imaging

The 3.0 T scanner is the first Philips 3.0 T scanner in North America, and has the same user-friendly geometry as the 1.5 T scanner.   Gradients on both machines have been updated and are dual-mode systems:  The 1.5 T system runs at 60 mT/m with a slew rate of 75 mT/m/s, and at 30 mT/m with a slew rate of 150 mT/m/s.  The 3.0 T system runs at 80 mT/m with a slew rate of 110 mT/m/s, and at 40 mT/m with a slew rate of 220 mT/m/s.  

Both scanners have multi-channel receiver systems and high-sensitivity multi-element receive-only head coils, allowing for parallel imaging, including sensitivity encoding (SENSE) for faster scanning.

The center is scheduled to be upgraded in 2008 with the addition of a 7.0 T scanner and expension of the office area.

Because much of the research in the Center pertains to functional MRI, the scan rooms have been designed with optimum radio-frequency (RF) shielding. No RF producing equipment is used in the scan rooms without proper shielding; indeed most such equipment is located outside of the scan rooms: The video projectors for fMRI visual stimuli are outside the rooms; waveguides integreated into the room's RF shield allow for video stimuli to be projected onto rear-projection screens (mounted in the back of the scanner bore) which is viewed by participants using a mirror mounted atop the headcoil. The center also features dedicated air conditioning of the equipment rooms (65 degrees F) and dedicated power conditioning to enhance MRI temporal stability.  A 100 kilowatt uninterruptible power supply (UPS) provides continuous conditioning of the electrical power for each scanner, shielding the gradient and radiofrequency amplifiers from any fluctuations in building power.

Dedicated pentium PCs and Macintoshes are available for paradigm presentation; these are connected via custom triggering circuits so that stimulus provision may be triggered by and hence synchronized with the scanner.  FMRI-compatible button boxes (using fiber optic communication), auditory equipment (using air-tube conduction), fMRI-compatible EEG equipment (using optical isolation) and in-magnet subject eye-tracking (using infrared imaging) are in place.

The computer of the Kirby Center is a SunFire V880 Server with 8 parallel processors, with a total of 16 GB of RAM memory. Storage capability of this computer consists of 288 GB of RAID storage plus 6 TB tape "jukebox."  Installed software includes AFNI, FIDAP, IDL, MATLAB, MEDx, and SPM.  Eight Sparc Ultra10 workstations, a SunFire V880z 2 CPU workstation, a dedicated MRI pulse-programming VMS workstation, plus assorted Macs and PCs, are connected via a fast (100 BaseT) network.

The center also contains a "mock scanner" for the training of subjects.  This full-scale model of our scanner was built using a scanner cover provided by Philips Medical Systems, and is used for acclimatizing subjects to the MR environment; this is especially useful for training children, the elderly, and persons with psychiatric disorders, in order to reduce head motion during scanning.



[provided by J.J. Pekar; this version dated 5 April 2007]