On Monday, March 30th, Dmitry Novikov, Assistant Professor at NYU Center for Biomedical Imaging, will give a talk on breaking through the Magnetic Resonance Imaging (MRI) resolution limits to the tissue microstructure below.
 
MRI allows clinicians to see structures as small as one millimeter, roughly at the resolution of unaided human sight. At this scale, we can distinguish tissues—but not individual cells they’re composed of. “It’s a hard limit,” said Dr. Novikov in an interview, noting that to see such minutiae through MRI in vivo radiologists would have to scan patients with prohibitively strong magnets for extraordinarily long periods. In other words, “you cannot buy your way out of the limit”—but you may be able to think your way out.
 
In his lecture, titled Seeing the invisible: Tissue structure at the cellular lever with MRI, Dr. Novikov will talk about using MRI to glimpse microstructures one thousand times smaller than one millimeter. “That’s where physiology happens, that’s where pathology develops,” he noted. This relatively new and still emerging way of seeing depends on taking MRI measurements with conventional millimeter-scale resolution, and developing theoretical models to interpret the resulting data in terms of changes occurring at the scale of microns.
 
Dr. Novikov’s lecture is a part of the Translational Research In Progress (TRIP) Seminar series hosted by the Clinical and Translational Science Institute, an interdisciplinary partnership among New York University, the NYU Langone Medical Center, and the New York City Health and Hospitals Corporation.
 
Details: Monday, March 30th, 1:00pm, Smilow Research Center (map), 1st Floor Multipurpose Room.

In the June issue of the Journal of Magnetic Resonance Imaging, Dr. Raya, who develops methods for early detection of osteoarthritis, describes diffusion tensor imaging (DTI) techniques for assessment of cartilage composition and structure. In particular, he employs two DTI measures—mean diffusivity and fractional anisotropy—to evaluate two fundamental elements of cartilage tissue—proteoglycan and collagen.

The images on the cover of JMRI show longitudinal changes in DTI measurements of the knee in two patients diagnosed with osteoarthritis. The data indicate that proteoglycan content may decrease even as the structure of collagen fibers remains relatively stable. The results also demonstrate that diffusion parameters can characterize physiological changes occurring over time. Read about this and related techniques in Dr. Raya’s paper, Techniques and application of in vivo diffusion imaging of articular cartilage.

An advocacy based in Washington, D.C., the Academy of Radiology Research champions recognition of the role of imaging research in medical practice, and advocates dedicated funding for imaging technologies that profoundly influence healthcare.

This year the academy has honored Dr. Fernando Boada alongside 36 researchers “for their accomplishments in imaging research” and to “especially encourage those who have achieved scientific excellence while still being involved in clinical care,” according to a congratulatory letter from the Distinguished Investigator Council.

As principal investigator, Dr. Boada leads a technology research and development (TR&D) project to develop convergent MR-PET acquisition and reconstruction methods that go beyond the conventional superposition of MR and PET data.

In a Q&A with MRM, Li Feng, PhD, and Ricardo Otazo, PhD, discuss XD-GRASP, an imaging method that combines golden-angle radial sampling with compressed sensing to track and freeze periodic motion.

"XD" in "XD-GRASP" stands for "extra dimensional," because the technique captures more than the four dimensions we experience directly (length, width, height, and time). The method enables reconstruction of additional dimensions associated with periodic motion, such as the cycle of heartbeat or breathing.

With XD-GRASP, organs affected by periodic motion can be "frozen" after reconstruction. The heart, for instance, which not only beats but also rises and falls, pushed up and pulled down by the diaphragm, can be shown and examined as if beating in a still environment, unaffected by breathing.

Watch Dr. Feng's presentation summary of XD-GRASP:

CAI²R Director, Fernando Boada, PhD, and CAI²R Principal Investigator Dan Sodickson, MD, PhD, convene with more than 130 scientists from over 20 other National Biomedical Technology Resource Centers and from the National Institutes of Health.

Dr. Sodickson will deliver a talk, The Changing Face of Biomedical Imaging: From Still Photography to Streaming Information, in which he will summarize the current state of imaging science, describe mounting demands for imaging to deliver greater measurable value in healthcare, and argue that the answer to those demands lies in development of rapid continuous comprehensive imaging technology. CAI²R is working toward making that vision a reality every day.

CAI²R and NYU School of Medicine team comprising scientists, clinicians, technologists, and graduate students will deliver over 100 research events, including educational talks, focused discussions, oral presentations, as well as electronic and traditional posters. 

The research team will present work in areas as diverse as:

• preclinical imaging
• MSK
• cutting-edge diffusion methods
• RF engineering
• new frontiers in image reconstruction
• breast cancer

and many, many more. For details, see ISMRM proceedings.

In a study published in Radiology, CAI²R researchers investigate possible association of fatty acid fractions of adipose tissue with breast cancer.

Using a novel method, multiple gradient-echo MR spectroscopy imaging, the investigators measured fractions of monounsaturated, polyunsaturated, and saturated fatty acid in breast adipose tissue of pre- and postmenopausal women with and without breast cancer. In the paper, authors write, “Our study demonstrated that, for postmenopausal women, low monounsaturated and high saturated fatty acids may be associated with invasive ductal carcinoma, which potentially makes them useful indicators of the presence of breast cancer.”

The method is non-invasive and can be “easily used in the clinic during a routine diagnostic protocol,” according to the authors.

Read the associated RSNA press release.
Read the associated NYU Langone press release.
Read the study: Evaluation of Breast Lipid Composition in Patients with Benign Tissue and Cancer by Using Multiple Gradient-Echo MR Imaging.

Although at many medical centers increased specialization has distanced radiologists from other clinicians, at NYU Langone radiologists participate in the clinical mix through virtual rounds and contribute nuanced analyses to collaborative patient care. Read The Wall Street Journal profile of integrative radiology operations at NYU Langone. 

Meanwhile, at NYU Langone's Center for Biomedical Imaging—home of CAI2R—imaging scientists are using insights from MRI applications of compressed sensing to develop ultra-low-dose CT. Read Radiology Business Q&A with CAI2R researchers about a new approach to CT dose reduction.

In research published today by Nature Communications, Drs. Cloos and Sodickson of CAI2R describe a multiparametric quantitative imaging method unaffected by RF field variations. The advance overturns decades-long assumptions about the necessity of pursuing uniform RF fields and opens doors to quantitative MRI results that accurately compare across scanners and patient populations.

The method, called Plug-and-Play MR Fingerprinting (PnP-MRF) has been validated in simulations, phantom studies, and in vivo. Read related press release by NYU Langone Medical Center. 

Organized by the Office of Science and Research at NYU Langone Medical Center on December 8, "Connecting the Dots" highlighted collaboration between NYU School of Medicine and NYU Tandon School of Engineering, and encouraged exploration of new joint research projects.

CAI²R scientists, Yvonne W. Lui, MD, and Riccardo Lattanzi, PhD, presented ongoing cross-disciplinary research conducted with colleagues from NYU Tandon. Dr. Lui (pictured) discussed the role of computational methods and advanced MRI in investigations of traumatic brain injury—a collaboration with Yao Wang, PhD, of NYU Tandon. Dr. Lattanzi, alongside colleagues from the schools of medicine and engineering, discussed collaborative investigations of medical image analysis at Tandon’s VIDA Center.

After presentations, scientists held a networking session to explore pressing challenges in biomedicine and bioengineering, and to envision new joint investigations. Dafna Bar-Sagi, PhD, Vice Dean for Science and Chief Scientific Officer at NYU Langone, challenged the teams to focus on the most timely questions, the disciplines that can best address them, and areas of particular opportunity.

Leon Axel, MD, PhD, addressed thousands of imaging scientists at the opening ceremony of the 25th annual meeting of the International Society of Magnetic Resonance (ISMRM)—held this year in Honolulu, HI—as he delivered the traditional Paul Lauterbur lecture, named after the inventor of MRI.

Dr. Axel, professor of radiology and professor of medicine at NYU School of Medicine, is best known for developing tissue tagging methods for cardiac imaging. A tireless explorer of the anatomy, physiology, and pathology of the heart, he leads a multidisciplinary group that develops new methods to image and better understand this singular organ. He is part of the CAI²R research team behind XD-GRASP, an information-rich, motion-robust, continuous acquisition imaging technique. The American Heart Association named him Distinguished Scientist in 2016 for contributions to the understanding of cardiovascular diseases and stroke.

At its 25th annual meeting, the International Society for Magnetic Resonance in Medicine (ISMRM) awarded postdoctoral fellow Thomas Benkert a Young Investigator Award for research that extends continuous imaging to fat/water separation. The awarded technique, called Dixon-RAVE, combines radial sampling, compressed sensing, and parallel imaging in order to deliver clear volumetric fat/water separation images even in the presence of motion. Robustness to motion eliminates the need for anesthesia and breath-holds, which simplifies the complexity of MRI exams for both patients and technicians, enhancing patient comfort and eliminating the need for costly, cumbersome repeat exams due to motion-induced artifacts.

The work builds on and extends continuous acquisition capabilities offered by GRASP, also developed at CAI²R, and has various clinical applications, including in liver and breast imaging, with special benefits for pediatric patients, geriatric patients, and all those who have difficulty performing breath holds.

Read the related publication.

Hong-Hsi Lee, MD, PhD, postdoctoral fellow at CAI2R, has been honored by the journal Brain Structure and Function and the Cajal Club with an Editor's Choice Award for a recent paper titled "Along-axon diameter variation and axonal orientation dispersion revealed with 3D electron microscopy: implications for quantifying brain white matter microstructure with histology and diffusion MRI."

The paper was chosen from more than 200 scientific publications that appeared in Brain Structure and Function in 2019. The award, usually presented at the meeting of the Society for Neuroscience (SfN), was announced on Sunday, October 25, at a virtual meeting of the Cajal Club, a society devoted to the promotion of neuroscience and named after the discipline's early pioneer Santiago Ramón y Cajal.