MRM Q&A posts
BY NIKOLA STIKOVNICU magnet – Jason Woods and Nara Higano
This month we are featuring a collaboration between the Cincinnati Children’s Hospital Medical Center, the Washington University in St. Louis and the University of Wisconsin – Madison. Nara Higano, Andrew Hahn, Jason Woods and colleagues used a converted orthopedic MRI scanner to measure tidal volume (the difference between lung volume in the inspired and expired state) in neonates. As you can imagine, we are talking small volumes here (on the order of tens of milliliters), and achieving this with 3D radial ultrashort echo-time (UTE) MRI is no small engineering feat that owes a great deal to some of the early MR projection reconstruction techniques.
March Cover Art
Optimal experimental design for filter exchange imaging: Apparent exchange rate measurements in the healthy brain and in intracranial tumors, by Björn Lampinen, Filip Szczepankiewicz, Danielle van Westen, Elisabet Englund, Pia C Sundgren, Jimmy Lätt, Freddy Ståhlberg and Markus Nilsson.
March Editor’s Picks
MR fingerprinting using the quick echo splitting NMR imaging technique, by Yun Jiang, Dan Ma, Renate Jerecic, Jeffrey Duerk, Nicole Seiberlich, Vikas Gulani and Mark A. Griswold. Audioslides.
Retrospective respiratory self-gating and removal of bulk motion in pulmonary UTE MRI of neonates and adults, by Nara S. Higano, Andrew D. Hahn, Jean A. Tkach, Xuefeng Cao, Laura L. Walkup, Robert P. Thomen, Stephanie L. Merhar, Paul S. Kingma, Sean B. Fain and Jason C. Woods.
BY MATHIEU BOUDREAU
The February 2017 Editor’s Pick is from Kimberly Chan and Richard Edden, researchers at John Hopkins University and the F.M. Kirby Center for Functional Brain Imaging in Baltimore. Their paper presents a study aimed at optimizing the echo time for measuring glutathione using J-difference editing. Glutathione is the brain’s main antioxidant, and may play an important role in several psychiatric and neurological illnesses, such as schizophrenia, bipolar disorder, and Parkinson’s disease. We recently spoke with Kim and Richard about their project.
BY RYAN TOPFER
Among the Editor’s picks for February comes a work from the Center for Magnetic Resonance Research at the University of Minnesota, where they’ve paired loops with dipoles for a novel hybrid transceiver. Last year, we featured the work of Alexander Raaijmakers (second author of the current work) on the fractionated dipole antenna design and we published the feature under the headline “We need antennas – not coils!” To understand this seeming about-face, we confronted Arcan and Greg over Skype about their decision to defy their collaborator’s unconventional wisdom.
BY BENJAMIN DE LEENER, NIKOLA STIKOV
In early 2017, the Highlights team had our first ever in-person interview with authors of this January’s Editor’s pick. For this historic event, we met with Gabriel A. Devenyi and Jamie Near, researchers at the Douglas Mental Health University Institute in Montreal, and authors of the recent MRM article “Advanced Processing and Simulation of MRS Data Using the FID Appliance (FID-A)—An Open Source, MATLAB-Based Toolkit”. It was noon on Friday, and we decided to get an early start on the weekend by heading to a most Canadian interview location – a skating rink at Beaver Lake in Montreal. Over beer and bison hamburgers, we discussed spectroscopy, open science, and the musical inspiration behind the acronym FID-A.
BY BLAKE DEWEY
In the early days of 2017, we sat down (virtually, of course) to have a conversation with Moritz Zaiss, Johannes Windschuh and Alexander Radbruch. Our topic was their recent MRM paper, “Downfield-NOE-Suppressed Amide-CEST-MRI at 7 Tesla Provides a Unique Contrast in Human Glioblastoma”. Chemical Exchange Saturation Transfer (CEST) imaging is an indirect imaging technique for the protons of certain metabolites, where saturation is applied off-resonance (with respect to water). Saturated protons are then allowed to exchange with water protons and then imaged using conventional imaging methods. However, frequency selection is not always enough to specifically target a functional group, such as amide groups, which are common in CEST imaging methods, producing a “mixed” contrast. Moritz, Johannes and Alexander, together with others in their group, have been slowly removing confounding effects in an attempt to isolate the measurement of amide proton transfer. In this paper, they continue their efforts by removing the downfield Nuclear Overhauser Effect (NOE), resulting in clinically relevant findings and correlation with gadolinium uptake in patients with glioblastoma.
BY MARK CHIEW
Two days after American Thanksgiving, we had the opportunity to speak with Lia Hocke, Yunjie Tong and Blaise Frederick about their recent MRM paper “Comparison of peripheral near-infrared spectroscopy low-frequency oscillations to other denoising methods in resting state functional MRI with ultrahigh temporal resolution”. Working out of the McLean Hospital, part of Harvard Medical School, they shared their perspective on the mutual information contained in peripheral NIRS (near infrared spectroscopy) and fMRI signals. They also used the word “photoplethysmograph” correctly in a sentence, and left us with a delightful shout-out to statistical rigor.
BY XIN MIAO
Dongwook Lee is currently a PhD student at the Korea Advanced Institute of Science and Technology (KAIST). He works on advanced image reconstruction techniques for dynamic MRI. His paper, selected as the Editor’s Pick for December, is entitled “Acceleration of MR parameter mapping using annihilating filter-based low rank Hankel matrix (ALOHA)”. ALOHA is a novel image reconstruction algorithm with the goal of clear, artifact free images acquired from very fast imaging schemes. For this paper, ALOHA was applied to accelerated MR parameter mapping, but could also be used for dynamic and parallel MRI, and even non-MR applications. We recently invited Dongwook and his supervisor, Dr. Jong Chul Ye, to talk about this paper.
α-trideuteromethyl[15N]glutamine: A long-lived hyperpolarized perfusion marker, by Markus Durst, Enrico Chiavazza, Axel Haase, Silvio Aime, Markus Schwaiger and Rolf F. Schultz.
December Editor’s Picks
Comparison of peripheral near-infrared spectroscopy low-frequency oscillations to other denoising methods in resting state functional MRI with ultrahigh temporal resolution, by Lia M. Hocke, Yunjie Tong, Kimberly P. Lindsey and Blaise de B. Frederick. Link to audio slides.
Acceleration of MR parameter mapping using annihilating filter-based low rank hankel matrix (ALOHA), by Dongwook Lee, Kyong Hwan Jin, Eung Yeop Kim, Sung-Hong Park and Jong Chul Ye. Link to audio slides.
BY THIJS DHOLLANDER
Recently, we had a chat with Elias Kellner, Valerij Kiselev and Marco Reisert from the University Medical Center Freiburg about their MRM paper entitled “Gibbs-Ringing Artifact Removal Based on Local Subvoxel-Shifts”. A challenge in time zone management, the interview was an early morning event for the MRM highlights editor (Nikola, in Montreal) and a late evening for the interviewer (Thijs, in Melbourne); however, that didn’t stop us discussing not only the paper, but also the art of paper writing and valuable lessons for the developers of novel acquisition strategies.