Yet another breakthrough in gradient technology

The picture above looks like a usual T1-weighted MR image but it was in fact obtained from a highly unusual set of gradient coils which was recently invented by GE. Called Magnus, the gradient coil inserts into a clinical 3T whole-body scanner to boost the imaging speed and gradient encoding power dramatically compared to a conventional scanner. The formal performance metrics are: 200 mT/m and 500 T/m/s, which compare with 80 mT/m and 200 T/m/s for the most expensive clinical scanner available today. What is even more important is that the design of the gradient coil, targeting specifically human head imaging, allows operation near the design limit without human peripheral nerve stimulation, which is known to limit gradient performance in conventional designs. This remarkable achievement was made from a team at GE Global Research in Niskayuna, NY, under a grant from US Department of Defense, and is well on its way to define the next generation of MR neuroimaging hardware. On a brief demo run, the team has shown high b-value (at 2000 s/mm^2) whole-head diffusion imaging with TE of 36 milliseconds!, which compares with a typical TE of over 60 msec in conventional scanners. The new gradient coil is planned to be installed in Walter Reed Military Medical Center in Bethesda, MD (near Washington DC) in the summer.

2018 KSMRM PhD Workshop

Last weekend the KSMRM PhD workshop was held in KBSI in Ochang, the same place as last year. This time the participants were limited to PhDs and the talks were generally lengthier. Even without students there were a good number of participants to make the sessions feel well-attended and well-prepared. The first day had sessions organized by Molecular Imaging study group and the Advanced MRI study group, and the MR Engineering session was held on the second day. For the lab, the MRE session was particularly useful and relevant, featuring RF technologies for ultra-high field MRI, presented by 3 speakers from the 3 institutes currently having a 7T human scanner in Korea. 

MR microscopy with human 3T MRI

The topic of MR microscopy is an old one. However, the IBS CNIR is uniquely positioned to put such a technique to good use, with numerous occasions to need multi-modality (optical and magnetic) imaging of ex vivo tissue samples from a variety of animals. In that regard, we have been looking into making an RF coil that is particularly suited to image thin flat objects, such as a brain slice mounted on a glass slide. Such a coil is known as "histology coil" and was developed originally by the Penn State group several years ago. Now students from Gachon University, working as undergraduate interns in the lab, made one such coil tuned at 123.25 MHz for use in our 3T MRI machine. The picture above shows a 40 um-think rat brain slice imaged at 3T with the special coil. It is impressive that although the imaging time was a good fraction of an hour, one can image such a thin slice in a human MRI scanner. Surely this will improve at 7T, 9.4T and higher which are all available in our building. This raises hope that we can soon produce research quality images of histology samples and push it for quantitative MR parameter mapping, and pursue other fun (crazy) research ideas.

Autumn is here! and events of the month

Autumn colors have descended on the SKKU Natural Sciences Campus. The semester is half done and from tomorrow begins the midterm exam week. Unlike the past couple of years, October this year has been relatively calm in the N Center without large center-wide events. A few things that have happened earlier this month are as follows. In reverse chronological order,

- October 20th (Sat): KSMRM's annual MRI training day for medical doctors was held in Catholic University St. Mary's Hospital in Seoul. Dr. Lee SK gave a lecture on k space. In all, 12 educational talks were delivered by the PhDs in each area of MRI.

- October 19th (Fri): Samsung Medical Center held the 5th Joint Symposium on Radiology with the Osaka University in Japan. This was held at the Cancer Center building of SMC, Seoul, and Dr. Lee SK gave a talk on 7T MRI at SKKU.

- October 15th (Mon): KSMRM staff gathered at a restaurant near the Seoul Train Station to discuss organizing a PhD-only workshop in November.

- October 4th (Thurs): The biannual graduate school open-house event took place in the main library and at the N Center. Student turnout for the BME department was similar to the last year (between 10 and 20).

SMC neurology team visit

A team of medical doctors from the SMC Neurology department visited the SKKU Suwon campus as part of the biannual collaboration meeting between SMC and CNIR. After short presentations by Dr. EH Baek and Dr. YM Sohn, the participants exchanged ideas on mutual collaboration in the fields of ex-vivo high resolution MRI of post operation tissue specimens and human 7T structural MRI using the Terra scanner at SKKU. The meeting proceeded over a working dinner in the 3rd floor meeting room, followed by a tour of the 7T magnet room where the head coil installation and patient table motion were demonstrated. There appears to be much potential for new research directions involving 7T. From today's discussion, high resolution imaging of cerebellum and hippocampus could be one of the first clinical research targets.

Memorandum of Understanding

New semester started with an external event involving official launching of the human 7T MRI scanner facility. The event was held on Friday 9/7 at the N Center with the University President and the Siemens senior management in attendance. Many students in the BME department's MRI research labs were also present. The event was covered in the school and public media as shown here. Apart from external exposure, the event provided an opportunity for the university and industry leaders to meet one another, and motivate young students to conduct their research in human MRI at SKKU.

7T MRI scanner user training

On August 1-3, Siemens provided a 3 day hands-on training for the general users of the 7T Terra system. Led by Dr. Ioannis Giapitzakis and Mr. Jongmoon Hahm, the educational sessions held in the N Center were well attended and helpful. The training consisted of a couple of lectures on high-field MR safety and principles, and demonstrations and practices on the center's new 7T scanner with plenty of user-instructor interactions. The system is currently not approved (by the Korean government) for routine patient scans, nor is yet cleared for research use on human subjects by the SKKU's institutional review board. So this time, the training included scans only on phantoms. What was particularly useful was detailed explanation/demo on general features of the scanner's user interface, which in large part are common between the 3T and the 7T scanners in the Center. This gave a chance to clear/resolve some of the doubts about scanner operation that many people have had before. The training sessions will continue when human scans are approved for either research or clinical use. For now animal and phantom scans can proceed without much delay. It does appear that the 7T system is well constructed for basic-level scans as a commercial product. It is noted that features and functions from the 3T scanner are relatively seamlessly transferred to the 7T system, to the benefit of both the users and the manufacturer.