Duke university visit

Early this month, an informal research meeting was held at Prof. Allen Song's laboratory at Duke University in North Carolina. Three people from GE Healthcare met with Allen, Prof. Dean Darnell, and a graduate student Devon Overson, to talk about MRI systems engineering to realize wireless receiver coils. This was a second visit in about two years. In 2022, when we were still wearing masks (picture on the left), we had a meeting on the "iPRES" coil, an RF receiver coil that doubles as a multi-channel shim array. The meeting this month, as before, was very productive. The Duke team has worked on wireless signal transmission for peripheral devices control for a number of years. It remains to be seen whether wire-free, battery-powered MRI RF coil can be realized without sacrificing the sensitivity to replace the traditional signal reception architecture.

ISMRM Abstracts, 2025

The meeting next year will be in Hawaii, a popular place, and the ISMRM organizers are sifting through more than 8000 abstracts submitted for presentation there. I have been critical to the abstract's HTML format, and a recently introduced sectioned Synopsis (in fact the presence of Synopsis at all). However, from an abstract reviewer's point of view, I must say these changes are helpful, to quickly get to know the work, and inspect details of selected figures. The organizers also did a good job in summarizing the review progress graphically in real time. This allows a reviewer to stay "normalized", by observing how the score distribution changes from start to finish as more than 50 assigned abstracts are scored. Certainly a lot of change has happened in ISMRM abstract processing since the early 2010s. I still hold up two things as suggestions to the Society: (1) The scores should be made available to the authors, and (2) All rejected abstracts should be given a chance to be archived, if not presented, on-line. That is democratization, not giving out low-performance MRI to those who deserve better.

MRI as a patient

I guess a web log dedicated to Magnetic Resonance Life is not complete without MR images of the author as a patient. For that purpose, I had an opportunity, albeit painful, to collect exactly such data in early November. The 1.5 T GE Signa Artist images shown above display "unremarkable" brain anatomical images with multiple contrasts following a standard protocol in Albany Medical Center. The total exam lasted for 21 minutes, and I must say the image qualities are pretty good for 1.5 T. The Center used apparent diffusion coefficient (ADC) to look for brain vessel blockage (infarct), and susceptibility-weighted imaging (SWI) for brain blood leakage (hemorrhage).

Three patent applications of summer of 2024

Three patent applications were published in July, that are all related to what is called concomitant gradient correction. This refers to magnetic field vector components that are unwanted but occurring as a byproduct of the desired magnetic fields in MRI. The three patents each address measurement, hardware-based correction, and software correction. The problem of concomitant field first came to me in early 2000s when I was a graduate student working on microTesla MRI with superconducting sensors. That work was reported here in a JMR article: https://pubmed.ncbi.nlm.nih.gov/19664947/. At that time the issue was too weak a main magnetic field; now the problem is due to too strong a gradient field. Different regime, but the same physics.

Three papers of summer of 2024

I was silent for 3 months! In those summer months, 3 papers of mine came out, in Journal of Applied Physics, IEEE Transactions on Magnetics, and Magnetic Resonance Imaging. They report studies related to, and motivated by, MRI gradient coils. The three papers, respectively, provide a first systematic mathematical formulation of magneto-mechanical coupling, derive a versatile, surface eddy current equation, and describe a practical method to reduce acoustic noise in high-performance MRI. They all center around solving critical engineering problems in high-field, high-gradient MRI, in order to make strong magnetic fields more accessible and exploitable for advanced brain imaging. Apart from the subject matter, a not-so-coincidental feature that is common to all three papers is that they have a non-sectioned, single-paragraph abstract! They are also in journals where authors don't have to pay to publish.

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. 

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!