About 4-D: Experience

Experience

4-D Neuroimaging has installed more large-scale MEG Systems than any other Manufacturer.

4-D Neuroimaging, formerly known as Biomagnetic Technologies, Inc., installed the first MEG systems for human study at UCLA and the National Institutes of Health in the mid 80s. since then, 4-D has installed over 50 MEG systems throughout the world.

The first MEG systems were single channel systems with 2nd order gradiometer detector coils that could operate in an unshielded environment.

Figure 1. The First single-channel MEG instrument. Installed at the NIH.

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Soon, however, the demand for more sensitive instruments mandated that MEG systems be developed with 1st otder gradiometers, as in the first clinically useful MEG systems, the 37 channel Magnes I and II systems, physicians around the world developed standard protocols for epilepsy surgery evealuation and pre-surgical functional mapping of eloquent cortex.

Clinical studies utilizing the Magnes I and II, and Magnes 2500 WH systems on over 5,000 patients during the 90s provided the necessary documentation of clinical efficacy for the American Academy of Neurology to successfully seek issuance of CPT codes for reimbursement of clinical MEG studies in the U.S. in 2002, and for the determination of reimbursement amounts published in 2003.

Figure 2. The first clinically useful MEG system, the 37-channel Magnes I system.

Figure 3. The dual hemisphere 74-channel Magnes II system.

Further experience with clinical applications such as epilepsy surgery evaluation dictated the development of MEG systems that could reliably measure the signals from deep epileptic sources within the mesial temporal lobe. The answer from 4-D was the magnetometer-based Magnes 2500 WH and Magnes 3600 WH systems. Magnetometer-based MEG systems are far more sensitive than gradiometer-based systems, and require a level of experience that only 4-D can provide, not only to develop the instrumentation, but to install the systems and train operators of the equipment.

In addition to on-site training during system installation, 4-D provides in-depth training for researchers, technologists and clinicians at selected customer sites around the world. There are currently over 30 large-scale 4-D MEG systems in operation worldwide.

Figure 4. The most advanced research and clinical MEG system, the 248-channel Magnes 3600 WH.

4-D Neuroimaging provides a comprehensive program of site planning and complete installation service for all 4-D systems. 4-D engineers work with hospital and university architects and planners, from the beginning, to insure that the site is optimally configured for MEG studies.

Figure 5. The site plan developed by 4-D engineers in conjunction with the staff of the New York MEG Center.

Careful planning and optimum design of the Magnes whole head has allowed 4-D to successfully install and support operation of magnetometer-based systems in major urban environments, such as New York City, Tokyo and Madrid.

Figure 6. The Magnes 2500 WH MEG system at the Complutense University in Madrid is completely surrounded by the city subway system. This site has the most environmental noise of any site 4-D has evaluated. The system operates flawlessly with 4-D noise suppression software.

Figure 7. 4-D has installed two magnetometer-based MEG systems in one of the busiest sections of New York City. Note the proximity to subways and rail lines.

4-D Neuroimaging®,®, and Magnes®
are trademarks of 4-D Neuroimaging.