NMR/MRI Research Facilities
The primary instrument of the Resource is a 7 Tesla whole-body Siemens MRI scanner is located in the basement of the Stellar Chance Building on the School of Medicine campus. It is dedicated to 100% multi-nuclear MRI research. The system is capable of performing imaging and spectroscopy studies on a variety of NMR visible nuclei, including 1H, 31P, 13C, 23Na, 19F, 17O, 7Li, 14N, 15N, 129Xe, and 3He. The pulse-programming environment allows for development of sophisticated pulse sequences. The 7T system is equipped with a 32-channel head coil. This system also includes RF coils for 31P and 13C NMR spectroscopy and a custom hybrid head/neck coil for arterial spin labeling. A parallel transmission system is also available and can be used in conjunction with an 8-channel transmit/receive array. An outboard GPU processor has been interfaced with the 3T and 7T systems to allow rapid image reconstruction for multiband EPI and other high-throughput imaging. Sequences performed at the Resource have included T1ρMRI, Sodium MRI, multiple quantum spectroscopy and imaging, MR elastography, localized spectroscopy, and perfusion imaging.
Additionally, the Department of Radiology currently houses Siemens Sonata and Symphony scanners operating at 1.5 Tesla and 3.0 Tesla. The research scanners operated by the Center for Advanced Magnetic Resonance Imaging and Spectroscopy are located within the Hospital of the University of Pennsylvania and are staffed with MRI technologists skilled in imaging research protocols. The scanners are equipped with full physiological monitoring capabilities, crash carts, and are accessible to Hospital code teams. All scanners are capable of parallel imaging and equipped with a variety of RF array coils. An on-site engineer is available to maintain the scanners in the event of technical malfunction.
A Siemens Magnetom Trio 3T whole-body MRI system is managed by the Center for Functional Neuroimaging exclusively for neuroscience neuroimaging and includes a 32-channel head receiver array. Extensive ancillary instrumentation is available on this system for fMRI, including projection systems, audio systems, video monitoring, pupillometry and eye traking, button/joystick, trackball interface, and noise cancelling microphones.
A second neuroscience dedicated 3T MRI (Siemens Prisma) system has been ordered for installation in the basement of the Stellar Chance Building in an unoccupied bay in CMROI adjacent to our 7 Tesla whole-body system. This system will have a 64-channel head/neck receiver and “connectome” gradients. This system is scheduled for installation in the spring of 2015.
Mock MRI Scanner. A full-sized mock MRI scanner fabricated from the shell of a decommissioned 1.5T GE Signa MRI system is located in the CfN/NNC, approximately 2 minutes from the real MRI scanners and is equipped for fMRI stimulus delivery, synthetic scan sounds, and real-time inertial head movement monitoring.
MRI Compatible EEG System. BrainAmp MR Plus system (Brain Products, Gilching, Germany) for recording EEG signal in the MR scanner simultaneously with fMRI acquisition. The hardware of this system consists of a MR compatible amplifier, two MR compatible power supplies, four 32-channel MR-compatible caps, and three 14-channel MR-compatible caps specifically designed for sleep study. This system also includes a complete set of softwares, including the Recorder for multifunctional EEG signal recording, the Recview for real time data analysis, and the Analyze 2 for offline data analysis.
MRI Compatible TMS System. A MagVenture MRI compatible system configuration based on the MagPro X100 with MagOption magnetic stimulator and the MRi-B91 coil is on order for use with our new 3T MRI system. This device provides the flexibility to do up to 100 pps (100Hz) stimulation rates. Besides the Biphasic waveform, it also offers capabilities to do Monophasic, Half Sine and Biphasic Burst (Theta Burst) waveform by simple selection from the screen menu, offers versatile trigger in/out capabilities to ensure easy interface with EEG, EMG and EP equipment, monitoring and read out of the realized output values (di/dt), storing and transferring stimulation/ system status data for each and every pulse in any given protocol. Within the user interface users can design and store up to 27 different protocols which can be easily recalled by simply push of a button.
MRI Compatible tDCS System. The neuroConn DC-STIMULATOR PLUS is a micro-processor-controlled constant current source. It features multistage monitoring of the current path and by continuously monitoring electrode impedance it can detect insufficient contact with the skin and automatically terminate stimulation. A remote mode enables external control by a voltage supply source and filter boxes and cables are available for operation within an fMRI scanner. The fMRI module module allows artifact-free MR images even during EPI sequences and has been tested for 1.5 and 3 Tesla scanners.
Animal MRI Scanning. The MR laboratories in the Small Animal Imaging Facility (SAIF) are located in two facilities: in the basement of the John Morgan Building in the Perleman School of Medicine and in the basement of the Founders Building of the Hospital of the University of Pennsylvania. The Morgan facility houses a state of the art Varian 9.4 Tesla horizontal bore small animal MRI system. This system is equipped with 12 and 21 cm gradient insert tubes with maximum gradient strengths of 40 and 20 G/cm and a switching time of 200 µsec (Magnex Scientific, Abingdon, UK). This system is interfaced to a multi-nuclear dual channel DirectDrive console (Agilent, Palo Alto, CA) with full gradient and RF shaping capabilities and four-channel receiver array. The receiver train of the DirectDrive console digitizes the data at the full bandwidth of the IF (20 MHz) with 14-bit resolution. The system is equipped with a variety of coils including; a 72 mm ID dynamically detunable linear birdcage, a 4 channel phase array coil suitable for rat brain imaging, a 4 channel phase array coil suitable for mouse brain imaging, a 20 mm ID circularly polarized birdcage suitable for mouse brain.
A newly constructed preclinical imaging lab located in the Smilow Center for Translational Research adjacent to the Perelman Center for Advanced Medicine now houses a 4.7 T 50 cm horizontal bore and a 9.4 T 8.9 cm vertical bore animal MRI scanners. The consoles on both systems were upgraded in 2009 and 2010 to the DirectDrive consoles. The 4.7 T system is equipped with a 39 cm ID gradient tube with a maximum gradient strength of 3 G/cm and a 12 cm ID gradient insert with a maximum gradient strength of 25 G/cm. The upgrade included a 4-channel receiver array and an assortment of M2M RF coils that include a dynamically detunable 72 mm ID linearly polarized birdcage, a 4 channel phased array suitable for mouse brains, a 4 channel phased array suitable for mouse brains, a 20 mm circularly polarized birdcage suitable for mouse brains, a 35 mm ID circularly polarized birdcage suitable for rat brains, and a 72 mm ID circularly polarized birdcage suitable for rat abdomens. A fully equipped animal surgery room is adjacent to the MR installation, with the facilities for surgery and animal preparation for MR imaging of large and small animals. A 3 Tesla Siemens Trio (clinical) system is also installed at this location for large animal MRI.
The 9.4 T vertical bore Is a three-channel Direct Drive system is equipped with 5 mm, 10 mm and 20 mm Varian and Doty double and triple tuned multinuclear high resolution probes. The system is configured with a 55 mm ID 100 gauss/cm gradient insert. A variety of resonators specifically designed for observation of tumor xenografts in mouse models have been constructed in house for use with this system. In addition, 20 mm ID and 11 mm ID resonators suitable for high resolution MR microscopic imaging and high resolution diffusion tensor imaging of fixed rat and mouse brains are available for use with this system.