Area:
Biomedical Engineering, Radiology, Electricity and Magnetism Physics
We are testing a new system for linking grants to scientists.
The funding information displayed below comes from the
NIH Research Portfolio Online Reporting Tools and the
NSF Award Database.
The grant data on this page is limited to grants awarded in the United States and is thus partial. It can nonetheless be used to understand how funding patterns influence mentorship networks and vice-versa, which has deep implications on how research is done.
You can help! If you notice any innacuracies, please
sign in and mark grants as correct or incorrect matches.
Sign in to see low-probability grants and correct any errors in linkage between grants and researchers.
High-probability grants
According to our matching algorithm, Yu-Chung N. Cheng is the likely recipient of the following grants.
Years |
Recipients |
Code |
Title / Keywords |
Matching score |
2010 — 2011 |
Cheng, Yu-Chung Norman |
R21Activity Code Description: To encourage the development of new research activities in categorical program areas. (Support generally is restricted in level of support and in time.) |
Determining Properties of Subvoxel Objects From Mri Images
DESCRIPTION (provided by applicant): The measurement of magnetic properties of tissues in the human body is fast becoming a key element in studying disease with magnetic resonance imaging (MRI) and in molecular imaging. The magnetic properties of a subvoxel object usually cannot be determined from a given magnitude image in MRI. Although the magnetic susceptibility difference between an object and its surrounding tissue leads to a signal loss in the nearby tissue, the combination of magnitude and phase images can be used to quantify the magnetic property of any given object in MR images. A novel inverse method using this feature will be fully developed in this proposal, especially for a few voxel or subvoxel objects. This method requires the use of complex MRI data and naturally accounts for the partial volume effect, dephasing effect (i.e., signal loss), and the phase aliasing effect. Compared to other methods, this method does not require any a priori information of the object of interest. The uncertainty of the method depends on the signal-to-noise ratio and resolution of images. Three specific aims are proposed in this research. The first aim is to determine the magnetic moment of a spherical object and an infinitely long cylindrical object. The former represents a 3D problem while the latter represents a 2D problem. Fundamental electromagnetism guarantees that the magnetic moment of any small object in 3D can be well approximated by the magnetic moment of a sphere. Both simulations and phantom experiments will be conducted to validate the method and investigate the uncertainty of the method. The second aim is to apply the method on existing human and animal images. This is to demonstrate the feasibility of the method on practical images. The third aim is to resolve the magnetic susceptibility and volume of the object individually. Since it is obvious that the volume of an object much less than a voxel such as a nanoparticle in images cannot be determined, it is important to study the limitation of the proposed method. This work could have a major impact on studying aging or molecular imaging through the use of nanoparticles. Evidence indicates that 2-amyloid plaque is related to Alzheimer's disease. Animal studies have shown that amyloid deposits lead to hypointense spots at an early stage of Alzheimer's disease. Quantification of the property of each individual dark spot may become a predictor for monitoring the progression of the disease. Currently, no non-invasive tool other than number counting is available for accurately quantifying microbleeds or hypointense spots in the brain. Nanoparticles have been widely used in MRI for tagging cells in molecular imaging. A reliable in vivo method is needed to quantify the concentration of nanoparticles labeling cells that interact with diseased tissue. This method can do that with numerous identical nanoparticles. In summary, this research has the potential to contribute to the better diagnosis and function of disease in MRI. PUBLIC HEALTH RELEVANCE: The proposed method may become a predictor of Alzheimer's disease in the long run. It may become a useful tool for the design of personalized medicine. The benefit of this research to the public health is obvious.
|
1 |
2021 |
Cheng, Yu-Chung Norman Counts, Scott E (co-PI) [⬀] |
R21Activity Code Description: To encourage the development of new research activities in categorical program areas. (Support generally is restricted in level of support and in time.) |
Magnetic Susceptibility and Volume of Microvascular Lesions as Proof-of Concept Biomarkers For Mixed Dementia
Project Summary The objective of this R21 proposal is to give proof that magnetic susceptibility and volume of cerebral microbleeds quantified by an innovative MRI technique, CISSCO, and validated by pathological examination can differentiate postmortem brain samples from control and demented subjects. Microbleeds appear in varying numbers in images, but they are strongly associated with vascular cognitive impairment (VCI), small vessel diseases (SVD), and Alzheimer's disease (AD). They also appear in healthy older people at a lower prevalence. Current clinical diagnosis only counts the number of microbleeds and their mimics from images. However, the number of these ?apparent? micro-objects is subject to imaging parameters (including the MRI field strength) and does not correlate well with the progression of cognitive decline. As microbleeds with hemorrhagic components show magnetic susceptibility effects in MRI, these investigators hypothesize that magnetic properties of microbleeds may help to differentiate certain clinical dementia subtypes. These novel quantitative parameters may be better markers for incipient dementia. They will advance our current understanding of the contribution of microbleeds to dementia beyond postmortem analysis and toward living patients. To design clinical imaging protocols and parameters, susceptibility values of microbleeds used to distinguish between control and demented subjects must be known first. The proposed aims are to image and pathologically examine micro-objects in postmortem samples obtained from the Michigan Brain Bank (MBB), which will blind these investigators to the clinical and neuropathological diagnosis of each subject until the late stage of this project. Formalin fixed, paraffin-embedded blocks where microvascular lesions are suspected will be obtained from subjects who died with no cognitive impairment or mixed dementia (including cases with high- and intermediate- likelihood of AD pathology). The CISSCO method will be applied to MR images of postmortem samples for accurate quantification of the magnetic susceptibility and volume of each micro-object. These micro-objects observed in MRI will then be co-registered and identified histologically in the same samples. These micro-objects, which are microbleeds and their mimics, will be categorized based on pathological results and quantified susceptibility values from MRI. They will also be compared between the diagnostic groups after the investigators are un-blinded. Cox hazard ratios will be calculated for different categorized results. If different magnetic properties can differentiate the clinical groups, then this outcome would indicate that magnetic properties of microbleeds is a potential advance in imaging biomarkers for dementia. With proof from this R21, future clinical testing plans will be proposed to NIH.
|
1 |