Saturday, June 8, 2024

Head-only then and now


In this year's ISMRM meeting, accessibility, Helium-free magnet, and high-performance gradients were at the top of many people's mind. In 2016, GE's 3T head-only scanner already combined all three. The figure above compares the 2019 ISMRM floor (right) showcasing GE's then-latest ESP head-only scanner, with this year's floor in Singapore (left) where MAGNUS 3T was unveiled with much acclaim. ESP didn't pan out; time will tell if MAGNUS will. 

About Low-field: This year's ISMRM was flooded with low-field MRI presentations in all formats. Anyone who was in the MRI field long enough will know that performance is the key. Did the bar go down in the name of democratization? Will AI magically lift the SNR? Or is MRI undergoing a transition from a physics and engineering wonder to commodity electronics? Maybe all of the above. Something good may well come out of this, but I sincerely hope that the trend is guided by unselfish, conflict-free, balanced and broad view of MRI's place in medical imaging. 

Saturday, April 20, 2024

Digital posters for ISMRM 2024

 
ISMRM announced proceedings of this year's scientific meeting on its website. The digital posters are now presented as an author-recorded video (in most cases, a power point with narration) in a common wrapper which contains links to section headings. This reduces the video screen size but helps audience keep track of the contents in context. Two such posters of mine are shown in screen captures above. Availability of remote participation was certainly accelerated by the pandemic, and may contribute to lower in-person attendance from regions far away. Good luck with all those who travel to Singapore in May!

Tuesday, April 16, 2024

DIANA questions, raised scientifically

 A first scientific counterargument against DIANA was published recently in an open-access journal: A different interpretation of the DIANA fMRI signal | Science Advances. The three main points are the following: (1) The authors did reproduce the original MRI data and therefore the original report by Toi et al. in Science is likely true on observed facts. (2) On the other hand, the authors could explain their own observations better without invoking neuronal response, but rather based on instrumental artifacts and coincidental circumstances. (3) Regarding membrane potential-induced T2 change, the authors believe that the originally reported in-vitro T2 change is rather caused by cell swelling than membrane potential. The authors did leave several questions unanswered that need to be answered in order to reconcile their assertion with the large amount of experimental data reported in Toi et al.

It is notable that the authors humbly titled their paper as "A different interpretation of DIANA fMRI" and showed reservation of judgment and desire to be constructive. The paper ends with a respectable remark, "Although the goal of probing neural activity with millisecond temporal resolution using fMRI remains unmet, we hope that the contribution of Toi et al. will inspire further efforts to achieve this ambitious and worthy objective."

The questions raised by this paper are certainly serious and substantial. But they were brought up in a way to allow professional debate and objective mutual verification. I hope this development, along with the growing body of positive data from Prof. Park's team, will soon bring clarity to this tantalizing DIANA puzzle.


Wednesday, March 20, 2024

Installation finished

Brigham and Women's hospital in Boston now has the latest Magnus gradient system which started to generate beautiful brain images!

[Update] An opening ceremony for the Magnus imaging facility was held on March 28th in a nearby Brigham and Women's hospital building with the senior leadership of the hospital. It was a nice showcase of an exemplary co-work among the government, industry, and academia. It is only the beginning!

[Link] A website (https://brighamandwomens.theopenscholar.com/magnus/) introduces the State government-funded Magnus program.

Sunday, February 25, 2024

Installation under way

 

Installation of a brand-new Magnus gradient system is under way in Brigham and Women's hospital in Boston. This was funded by the Massachusetts Life Sciences Center (link to grant news). Prof. Westin, the PI on the right in the picture, indicated that the users will be split half and half between clinical and physics/engineering research. Brigham and Women's hospital has many campuses across the area. The Fenwood location, where the 2023 neuroimaging conference was held, had received the country's second clinical 7T MRI machine from Siemens in 2017. (That's why the name may sound familiar to those involved in the 7T commotion in Korea.)

Saturday, January 27, 2024

ISMRM abstract announcement

This year's ISMRM abstract announcement came a week earlier than usual. In my count, about 143 x 36 = 5148 abstracts were accepted, as compared to 141 x 38= 5358 last year. I see submission numbers going beyond 8600 so the acceptance rate is perhaps about 60%, quite low compared to the past. The question of fairness and transparency naturally arises as more people get rejection -- prominently missing any explanation. When Dr. Derek Jones, now president of ISMRM, visited us last year I did ask about providing some kind of scores or justification for abstract decisions. He was under impression that rejected ones are of obvious low quality, and the question may be more on oral vs posters. I think this position needs re-visiting, as (i) the field is getting ever more diversified, making judgement of others' work difficult, and (ii) unlike APS, for example, ISMRM abstract submission requires considerable manual work (on formatting) so the rejected authors deserve some sort of feedback at the minimum.

Personally, two first-authored abstracts were accepted for digital posters as requested. They both involve eddy current. Video recording should happen in the next several weeks. More on that part later!

Monday, December 25, 2023

High performance neuroimaging conference in Boston

This was the second annual conference on MR neuroimaging and neuroscience enabled by high performance gradient coils. It followed the inaugural meeting at the GE Research center in December 2022, and was held in the Brigham and Women's hospital campus in Boston on Thursday 12/14, hosted by Prof. Carl-Fredrik (CF) Westin. Compared to the last one, the talks this year were more application-oriented than engineering, although there were interesting discussions on the comparison between GE's Magnus and Siemens' Connectome gradient coils. In particular, the current Connectome "2" user, Prof. S. Huang, gave a short talk on her team's experience with the new Siemens system. This helped make the conference take on a more vendor-neutral, academic forum-like atmosphere. Participants from all over the country and even outside (Lund university of Sweden), in addition to dozens (I think) of attendees from the local, BWH-Harvard medical school, appeared to reflect and echo a high level of community interest in high-performance* brain MRI. 

[*Note: High performance in this context means high-performance gradient coils, not necessarily dependent on static fields in excess of 3T. Both Magnus and Connectome gradient coils operate at 3T.]