Established in 2005, the Lurie Family Foundations MEG Center (within the Children's Hospital of Philadelphia Radiology Department) houses two state-of-the-art MEG systems (275-channel biomagnetometer VSM Medtech Inc. and 306-channel Elekta Vectorview) to measure brain function. In addition to these adult MEG systems, in the Spring of 2013 a 123-channel small-scale infant MEG was installed (Artemis 123™), a MEG system Drs. Edgar and Roberts designed in collaboration with Tristan Technologies Inc.. In addition to MEG, the Center also has three 3T MRI systems, including a state-of-the-art research-dedicated Siemens 3T Prisma MRI that provides high-resolution images of brain structure, brain microstructure and neurochemistry.
Magnetoencephalography (MEG) recording is a core methodology of the Lurie Family Foundations MEG Imaging Center (Director Timothy P.L. Roberts), a 1,330 sq. ft. laboratory within The Children's Hospital of Philadelphia Radiology Department. The three MEG systems are also equipped with capability for simultaneous 64-channel EEG.
Established in 2005, the laboratory is fully-staffed and committed to research and clinical excellence, while ensuring patient comfort and safety. In addition to nine dedicated PhD-level faculty, two staff computing specialists, three post-doctoral students, 7 research assistants and coordinators and 5 experienced technologists assist with and help support laboratory research. MEG data are primarily analyzed in the MEG analysis lab located within the Lurie Family Foundations MEG Imaging Center. In addition to the MEG analysis lab, office space is available in the Radiology Department for cognitive testing. Two waiting rooms (older child and infant/young child) are adjacent to the MEG laboratory and available for parental/guardian use during the child’s cognitive testing and cognitive/symptom exams.
Stimulus delivery systems include auditory (TDT attenuator/amplifier, Etymotic ER3A transducers), visual (high zoom), pneumatic tactile and electrical somatosensory (Digitimer) delivery systems as well as Lumitouch and Current Designs fiber optic response systems. Presentation™, E-prime (v1.1, 2 and 3) and PsychoPy paradigm delivery software are supported. Additional custom systems (e.g. for passive movement, or for gustatory/olfactory stimulus delivery) are available. Eye tracking for both Artemis 123 and CTF systems is available via a SR tripod-based system.
The Elekta Vectorview 306-channel MEG system
Magnetic Resonance Imaging (MRI) resources include dedicated research 3T Siemens Trio™, Verio™ and Prisma™ systems. The Trio and Prisma are housed in the Radiology Research division (CSH-1, Director: Timothy P.L. Roberts, Vice-chair), a 2000sq. ft. facility including MRI physicist/post-doc/research assistant office suites and analysis labs. The Verio system is in close proximity (2nd floor Wood Bldg) to both the clinical MRIs and the Research division suites. The Verio system, the Radiology Research Division suite and the Lurie Family Foundations MEG Imaging Center are only steps apart in contiguous spaces. The Prisma is equipped with connectome-quality 80mT/m gradients and is capable of multi-band accelerated acquisition (both SMS and CMRR C2P WIP). Both 32- and 64-channel head coils are available as well as a 16-channel neonatal/infant coil in addition to the standard 20-channel head/neck coil. The Prisma is also equipped with heteronuclear capabilities and coils for 3-He and 31-P. A mock scanner (PST) is housed within the Radiology Research Division suite, adjacent to a dedicated research participant waiting room. A second waiting/prep room is dedicated to young infants and is optimized for feeding and nursing towards sleep (dimmable lighting, nursing chairs etc.). A second, similarly specified and equipped, 3T Prisma™ is situated in the clinical department of Radiology at CHOP (2nd floor Wood Bldg) and is available for occasional research scheduling to cover the eventuality of research scanner downtime or scheduling conflicts. A master research agreement has been in place for many years facilitating collaborations between CHOP and Siemens and accelerating the incorporation of advanced technical developments (including WIPs for motion correction, diffusion and edited spectroscopy).
Stimulus delivery peripherals for MRI (primarily for fMRI applications) include auditory (Avotec / Sensimetric) and visual (Avotec, Resonance Technologies, In-Vivo) presentation systems and fiber optic response buttons (2x 2-button system from Current Designs Inc.). Waveguides exist for any additional required delivery/response systems. Presentation™, E-prime (v1.1, 2 and 3) and PsychoPy paradigm delivery software are supported. Eye-tracking is available using the SMI product in conjunction with the Avotec system.
The Siemens Prisma 3T MRI
Behavioral and Clinical Components
The research program in CHOP radiology additionally comprises two faculty neuropsychologists and masters and PhD-level clinical assessment and evaluation staff, Evaluation rooms exist in close proximity to the research MRI facilities in the Wood Bldg. and Children’s Seashore House. Additional behavioral testing and clinical evaluation space is available a short walk away at the Roberts Center for Pediatric Research, South St., in the Center for Autism Research.
The MEG analysis room is equipped with multiple dual-monitor Linux workstations, high performance Dell desktop computers, 30” monitors, and a 500GB-2TB Performance RAID. Several standard Dell desktop computers for Microsoft Office functions (Word, PowerPoint, etc) are also available.
The Image Analysis Laboratory in the Department of Radiology at The Children's Hospital of Philadelphia houses Linux-based 3.8GHz Intel-Xeon image server and analysis workstations. The short-term server is directly connected to the MRI scanners, allowing DICOM image transfer; it is equipped with RAID-configured expandable 1TB serial ATA hard disks and 4GB RAM. Server and workstation software includes MatLab and IDL environments, the VoxBo™ image software, MRIcro™, ImageJ™, freesurfer, SPM, FSL and BrainVoyager for functional imaging and a variety of in-house code developments for physiologically-specific parameter mapping. Windows-based PCs additionally support irfanview™, MRIcro™, ImageJ™ and (in collaboration with Dr Mori at Johns Hopkins University) DTIstudio™ for white matter tractography. MEG packages supported include BESA, SPM, BrainStorm and FieldTrip as well as a variety of proprietary and in-house scripts, routines and executables; Workstations can be accessed locally, or from physician/researcher offices using X-emulators, including XWin-32™. Virtual machines (VM’s) provide standardized and remote access to most software tools (including MatLab, jMRUI, BESA) and connectivity to secure network file storage systems.
Data (all de-identified) are stored and analyzed on a CHOP storage area network (SAN). The SAN utilized in the study is an Isilon system, a global large file system and NAS share, currently with 389TB capacity and expandable to 14PB (petabytes). Data on the Isilon is secure and is automatically backed up twice daily. In addition to the SAN, for computationally intensive analyses, we have access to the CHOP cluster. This is a 38-node Dell cluster (2304 total processing cores), with the following features: 2 x head nodes, 36 x compute nodes (4 x 16 core AMD x86_64 processors, 128GB RAM). The cluster uses the Bright computing cluster management suite, with SGE for job scheduling and fourteen data rate (FDR) InfiniBand interconnects. Major software installations supported by the cluster include FreeSurfer, FSL and routines utilizing the MatLab environment.