The Richard M. Lucas Center for Imaging

The Richard M. Lucas Center for Imaging houses resources devoted to research in magnetic resonance imaging (MRI), spectroscopy (MRS) and X-Ray/CT imaging. Researchers in RSL and at the Lucas Center have pioneered MRI/MRS/X-Ray/CT technology while developing new techniques that benefit patients with stroke, brain disorders, cancer, heart disease, chronic pain, genetic disorders, joint disease and diseases of the spleen and liver. The Center supports collaborative and original research using human subjects and intact animal models.

Our facilities include three 3.0T whole-body MR systems and a 7.0T whole-body MR system, complete with patient/animal preparation facilities and image processing/readout workstations. The Axiom/Zeego Lab houses a C-arm X-Ray CT scanner that offers fluoroscopic scanning, and many other applications. A machine shop/workshop offers addition capability for miscellaneous hardware development including MRI coils and phantoms. Most of the over 100 people in RSL have office space in the Lucas Center for Imaging.

Lucas Mock MRI Scanner

Lucas Basement P020B

The MRI Simulator includes: ~60cm bore with tapered entry and flat façade with integrated control panel (Light, Fan, In/Out), lights, fan, speakers & subwoofer, motorized patient table with drag sensing safety stop, manual table release. A flat panel monitor is attached to the head coil for easy, high-resolution viewing of motion measurements, stimuli or movies for the scan subject.

MoTrak head motion tracking system that provides linear feedback of X,Y,Z movement and rotational feedback on X,Y,Z axis (Pitch, Roll, Yaw coordinate) based on user-defined thresholds.

Scanner sounds from a variety of MRI scan sequences are available including Localizer, High Order Shim, 2D T2-weighted FSE, 3D T1-weighted FSPGR, DTI, EPI, and ‘sprlio' (spiral in-out fMRI).

E-Prime® stimulus presentation software is available on a separate computer.

MRI studies require long periods of scanning with minimal participant movement. The procedure can be an unsettling experience for many participants causing excessive movement resulting in unusable data and lost funds. Special populations such as children, the elderly, and psychiatric participants, are often prone to claustrophobia and anxiety in the bore of a magnet, and consequently have a much higher rate of terminating the scan session before its completion. Some centers that have dealt with these populations estimate a 50%-80% failure rate. With the use of the MRI Simulator (also known as a mock scanner) this failure rate can often be reduced below 5%, minimizing data loss.

The MRI Simulator provides a realistic approximation of an actual MRI scanner to allow habituation and training of participants in an environment less daunting than a real scanner. The MRI Simulator introduces the participant to an authentic scanning environment, permitting them to gradually become accustomed to the scanning procedure and trained to minimize movements. Allowing the participant to acclimate to the scanner before the actual session helps to prepare them and encourages a calmer and more focused participant, ultimately resulting in more productive scanning sessions.

InSightec FUS Table

Investigators throughout the world are currently applying MR-guided focused ultrasound (MRgFUS) for non-invasive treatments of a variety of diseases and disorders. Typically, focused ultrasound uses a large area ultrasound transducer array outside the body, focused either geometrically or electronically, to a point within the body. The amplification provided by focusing (which can be on the order of 1000-fold) provides the means to generate significant ultrasound intensities deep within the body, with insignificant ultrasound intensities in the intervening tissue. We are working with InSightec who makes a variety of systems that are integrated into General Electric MR scanners. For brain applications, InSightec has a hemisphere array.

Magnetic resonance imaging provides the means to target the ultrasound beam to the tissue of interest, monitor the therapy with MR thermometry, and assess the treatment through the variety of contrast mechanisms available with MRI. While some targeting and assessment could alternatively be done with ultrasound, MRI is the only imaging modality that provides quantitative temperature mapping over a wide range of temperatures. The key to MR thermometry is the change in hydrogen bonding with temperature, which results in a change in the electron shielding of water protons, and changes the resonant frequency by approximately -0.01 ppm/°C. In practice, temperature images are calculated from the change in phase on gradient echo images.

MRgFUS Research

Our lab is doing research in many areas of MRgFUS. Technical areas of research to support clinical applications include improved thermometry and monitoring (especially in moving organs), focal spot visualization, MR-based phase aberration correction, and workflow improvements. In addition, basic science research in ultrasound-based neuromodulation is showing that ultrasound can modulate neuronal firing. More details on our research can be found in these webpages. The future of MRgFUS holds new non-invasive treatments for a variety of diseases and disorders and also an exciting array of technical and scientific innovations.