Archive for May, 2019


Gordon Lecture: Advanced MRIs in CNS

05/20/2019


Dr. Meiyun Wang is a neuroradiologist, Professor and Chair of the Medical Imaging Center of Henan Province and Chair of the Department of Radiology of Henan Provincial People’s Hospital. She received her M.D. from Southeast University in 1995, a PhD from Capital University of Medical Sciences in 2005, and then worked as a post-doctoral research fellow at the Massachusetts General Hospital, Harvard Medical School from 2006-2008. She became the Vice-Chair in 2008 Chair in 2016 of the Department of Radiology of Henan Provincial People’s Hospital in China.
Below is a summary of her presentation.

In this talk, the applications of three non-contrast enhanced advanced MR techniques, including Diffusion Kurtosis Imaging (DKI), Strategically Acquired Gradient Echo (STAGE) and a Length and Offset Varied Saturation (LOVARS) in central nervous system (CNS) were summarized.

DKI has been used to measure non-Gaussian diffusion, which has the potential to characterize both normal and pathologic tissue better than diffusion-tensor imaging. Some previous researchers have suggested that DKI might provide more accurate information about water diffusion. Dr. Wang's study showed that mean kurtosis values may provide additional information and improve the grading of gliomas compared with conventional diffusion parameters.

STAGE is an advanced Susceptibility weighted imaging (SWI) which can provide multi-contrast images in one scan, such as T1W, PDW, T1 MAP, PD MAP, R2* MAP, SWI, and even MRA images in 5 minutes. It is very helpful in early detecting and evaluating ischemia, brain trauma and some other CNS diseases.

Read more...

Gordon Lecture Series: Learning reconstruction and analysis for medical imaging

05/13/2019


Dr. Shanshan Wang is an associate professor at Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences. She received her dual Ph.D degree from the University of Sydney and Shanghai Jiaotong University respectively in information technologies and biomedical engineering. Dr. Wang was a finalist for the Australian John Makepeace Bennett Best Thesis Award and won the 2018 OCSMRM Outstanding Research Award. Her research interests include machine learning, fast medical imaging and biomedical signal analysis.
Below is a summary of her presentation

Inverse problems are ubiquitous in the field of medical imaging and image processing. Prominent examples include fast MR imaging and image denoising. The goal of these problems is to reconstruct or restore an unknown image from a set of direct/indirect measurements. However, due to the limitation of the acquisition time or the existence of noise, the obtained measurements are often corrupted or incomplete, which introduces big challenges for the reconstruction process and the following clinical diagnosis. In order to remove the noise or overcome the ill-posed nature caused by the insufficient measurements, it is necessary to explore the prior knowledge and utilize them to form constraints in the reconstruction process so as to make up for the missing or corrupted information.

Read more...
Dr. Kwon

Gordon Lecture: Activatable Molecular Probes for Optical Imaging

05/06/2019


Dr. Ick Chan Kwon is a Presidential Scholar at KIST-DFCI On-Site-Lab in Department of Cancer Biology, Dana Farber Cancer Institute Boston. He is a Tenured Principal Research Scientist of Korea Institute of Science and Technology (KIST). He received his B.S. and M.S. degrees in College of Engineering at Seoul National University and his Ph. D. in Pharmaceutics and Pharmaceutical Chemistry from University of Utah. After a post-doctoral training at CCCD in University of Utah, he joined KIST where he started his research on polymeric nanoparticle-based drug delivery system for antibiotics, anticancer drugs and gene therapy. He also pioneered in a research filed of Theragnosis, by combining molecular imaging and drug delivery system with smart nano-probes. He is a fellow of The Korean Academy of Science & Technology and a member of The National Academy of Engineering of Korea.
Below is a summary of his presentation

Dr. Kwon

For decades, molecular imaging which can monitor inter-/intracellular functions or molecular processes in an organism has provided valuable information for various research fields. Biomarkers such as enzymes, receptors and proteins can be utilized as a target of molecular imaging since they can provide information for early diagnosis and monitoring therapeutic effect of diseases. Among them, receptor-ligand interaction based molecular imaging technique has been emerging promising strategy in theragnosis of intractable diseases such as cancer.
In this talk, Dr. Kwon introduced epidermal growth factor receptor (EGFR) and CD 47 receptor-specific self-quenched imaging probes, which can emit fluorescence (activate) via de-quenching reaction in lysosome. His talk also included a simple noninvasive labeling and tracking technique for cell therapeutics via combination of metabolic glycoengineering and biootherogonal copper-free click chemistry, resulting in the cells being tracked via near-infrared fluorescence (NIRF), magnetic resonance (MR) and computed tomography (CT) imaging without cytotoxicity and functional interference.

Sepulcre article in Nature Medicine

05/05/2019


Dr. Jorge Sepulcre, an Assistant Professor of Radiology at HMS and Assistant in Neuroscience at the MGH Gordon Center, leads a lab that focuses on brain imaging studies aimed at the understanding of large-scale brain networks implicated in human cognition and neurodegenerative disorders.

His article titled “Neurogenetic contributions to amyloid beta and tau spreading in the human cortex.” has been published in Nature Medicine.

Summary:  Tau and beta-amyloid (Aβ) proteins accumulate along neuronal circuits in Alzheimer’s disease (AD). Unraveling the genetic background for the regional vulnerability of these proteinopathies can help understand the mechanisms of pathology progression. To that end, we developed a novel graph theory approach and used it to investigate the intersection of longitudinal Aβ and tau PET imaging of healthy adult individuals and the genetic transcriptome of the Allen Human Brain Atlas. We identified distinctive pathways for tau and Aβ accumulation, of which the tau pathways correlated with cognitive levels. We found that tau- and Aβ-propagation patterns were associated with a common genetic profile related to lipid metabolism, in which APOE played a central role, whereas the tau-specific genetic profile was classified as “axon-related” and the Aβ profile as “dendrite-related”. This is the first study revealing distinct genetic profiles that may confer vulnerability to tau- and Aβ-in-vivo-propagation in the human brain.