Mayo clinic's compact 3T scanner

This is the world's smallest 3T head scanner capable of 80 mT/m gradient performance. Locally known as MR55, this is now one of the many MRI scanners used in Mayo Clinic for human brain studies. The blue and red tapes on the floor indicate 100 G and 300 G, respectively, indicating how fast the magnetic field falls off away from the scanner. These pictures were taken on Dec 17th, 2021, when the scanner was undergoing a scheduled upgrade. 

icMRI 2021

 This year's icMRI conference was held in a hybrid format on November 5-6, with many in-person sessions especially for domestic participants. The CIEL team has presented two posters in MR Engineering, based on work that was done prior to August 2021. There were a total of 24 MR Engineering posters including power-pitch presentations.

Pete Roemer on screen

 

Pete Roemer, physicist and inventor of NMR phased array, appeared on screen in this year's high field MRI workshop hosted on-line by the university of Minnesota on Oct 20-22. He has recently retired from GE Healthcare, and is apparently working as a private consultant to Stanford University on gradient coils. He presented  his computational work on PNS (peripheral nerve stimulation) and MGI (magnet-gradient interaction) in high-field MRI. It was a rare and welcome opportunity to peek into contemporary research in gradient coil engineering from the eyes of a legendary expert in the field.

MRI accident in news

In October several news outlets reported a fatal accident involving an oxygen tank pulled into an MRI machine. The accident happened on October 14th in a South Korean city of Kim-hae, and killed a man in his 60s. A quick internet search revealed a few details:

- The hospital where this happened was Kap-Eul general hospital in the town of Jangyoo-dong.

- The hospital homepage lists a GE HDxt scanner (1.5T) as their MRI equipment.

- The hospital did not use the available in-room oxygen supply, and the tank was on a wheeled carrier which was also pulled into the magnet.

One thing that many news reports are saying incorrectly is that the MRI machine attracted the tank as the scan started, which ignores the fact that the magnetic field is always on. What must have happened is that the tank was moved, possibly slightly, by somebody and fell over the "magnetic cliff" near the bore entrance. Then its flying as a projectile is uncontrollable. This is tragic, and makes one wish to have some kind of magnetic barrier set up around the scanner. Above to the left is a drawing I made for an MRI engineering course in SKKU illustrating the abrupt magnetic pull of a shielded MRI magnet. 

On-line undergraduate research presentation

With the COVID crisis deepening yet again, this summer's undergraduate research presentation was done in an on-line format, using Microsoft Teams, on July 21. Sadly, this may well be the last official group activity for the members of CIEL; it is only hoped that less official activities and networking would continue among the members who have shared the same lab space for years. The presenter was Seok-Jin Yeo, a senior who has worked in the Lab since 2018. Mr. Yeo spoke about his work in the past semester (and year) on extending the susceptibility-induced B0 calculation algorithm to arbitrary orientations. This work combined many research elements in it -- good amount of mathematics, Matlab simulations, and experimental measurements of magnetic fields with a Hall probe and by MRI. The presentation was effective, and the on-line platform was satisfactory in engaging the audience from multiple locations smoothly. Thank you all who participated in the meeting!

KSMRM on-line education day

This year's KSMRM education day was held on June 19, 2021 in the form of a whole-day on-line lecture series. The lectures were streamed on-line from a studio that was set up in a conference hall provided by Guerbet Korea, in Gangnam-gu, Seoul. Out of the 14 speakers, 5 uploaded a pre-recorded video, 1 presented remotely on-line, and the rest (8) spoke in person from the studio. A total of 141 people registered for the event, and typically 80 ~ 90 people were logged in at any given time. This is the second time when the education day was delivered in a live stream format, following the last year's example. The sessions went smoothly without any major technical or logistical issues. Most of the lectures were on clinical applications of MRI, given by medical doctors in Radiology. Thank you all who helped prepare and wrap up this annual event successfully!

11.7T System at Gachon Univ.

 

Gachon university has recently acquired an 11.74 T MRI system from an Italian company, ASG Superconductors, which made a big local news (https://www.bosa.co.kr/news/articleView.html?idxno=2139691) a few months ago. The picture above was taken on the 28th of May at the site where it is being installed, the Neuroscience Research Institute (Song-do branch) in Incheon. The magnet is being vacuum-checked, and is not cooled down yet. The magnet is not actively shielded, and although configured to image a human subject (with about 56 cm accessible bore), will primarily be used for animal imaging for the near future, for regulatory reasons. While the field strength is already quite unique, what is even more interesting is that the system is being configured for a sequential PET scan through a rail  system connecting the two scanners. Prof. Kyoung-Nam Kim (left in picture), kindly provided a tour of the building with several photo opportunities.

2021 ISMRM virtual meeting

Same as the last year, the pandemic has forced the ISMRM meeting to be held entirely virtually. An international conference like this suffers from one big problem when it comes to on-line, at-home meeting: the time difference. Basically the sessions ran around the clock, and participants could only join when the time is favorable / manageable to them. Given such shortcomings, it must be said that there were on the other hand a number of advantages in this format. First of all, all activities can be digitized and made to leave trace, so for example one can record who viewed a given poster. Viewer questions on chatting windows are preserved for anyone to see. Recorded talks and videos can be re-viewed as often as one likes. Cost is saved, and one can take part in the meeting while not giving up  regular workhours. Meeting data from the two digital posters from the Lab are captured in the picture above. In an interesting session on future jobs in MRI, Yiping Du presented clinical MR physicist jobs in Asia. GE introduced Signa 7T in corporate symposium. Siemens was said to have presented a new powerful 7T head gradient coil. All these can be viewed later, an unexpected benefit of the pandemic situation.

Research Sketch -- PD iron

In a paper published on-line yesterday (https://doi.org/10.1007/s10072-021-05223-0), Minkyeong Kim and Seulki Yoo (two lead authors) presented results of an iron-sensitive MRI biomarker study in early Parkinson's diseases patients. This work started in 2017 as part of a broader 3T neuro MRI collaboration between SKKU and SMC, with the SMC team led by Drs. Jin Whan Cho and Jinyoung Youn. 

At least 19 PD patients and 16 normal volunteers were brought from SMC to SKKU for a 3T MRI scan, from which 14 patients and 12 healthy subjects' data were selected for analysis of iron-sensitive MR imaging. Part of the funding came from IBS, and part from SKKU intramural research grant of 2019. 

For a clinical study the work used relatively small number of samples. The novelty claim has been laid on the use of relatively homogeneous, early-stage PD patients and investigation of non-motor symptoms. The main finding of the paper is the existence of non-negligible correlation between certain non-motor symptoms (such as sleep disorder) and R2* values in deep brain regions (such as red nucleus, amygdala, and hippocampus). Since R2* is sensitive to tissue iron level, this observation suggested that iron in specific brain regions of PD patients may be indicative of non-motor clinical symptoms. 

Despite much effort and time spent in data collection and analysis, the study exposed limitations of using iron-sensitive MRI for clinical research. Most significantly from the Lab's point of view, the QSM results were highly variable among subjects, to a degree much greater than inter-group differences expected from early PD cohorts. Motion, head orientation, and other physiological factors appear to affect QSM much more than R2* and other established, magnitude-based contrasts. 

This observation, made early on in the project, strongly suggested the need of longitudinal studies to follow variation of QSM on individual subjects. Such studies can greatly benefit from the ability to post-process routine clinical MR scans collected in SMC. To this end, the team has looked into the possibility of including multi-echo GRE scans, including phase images, in the routine scan protocol at SMC. Hopefully this line of research will continue in the near future for more fruitful clinical collaboration.

2021 Spring semester started

In fact this year's spring semester started from late February. The campus atmosphere is still somewhat heavy and subdued because of the pandemic, but the number of students and other pedestrians on and around the campus has clearly increased from a month ago, and also when compared to about this time last year. More classes are being offered in-person, and the degree of fear for the unknown appears to be less intense. The Lab now has officially 5 graduate students, after welcoming Jun-Ho Kim in to the incoming class. To celebrate this and other events (see News for publication updates), back-to-back small-group lunch meetings were held (as mandated by the local health authority) in the past week. May this semester be another successful one with continued progress in work and personal developments for all.