NINDS Quantitative MRI Core Facility

National Institute Of Neurological Disorders And Stroke

Investigators

Linked publications & trials

Abstract

- Brain segmentation algorithms: Neurological diseases can alter the brain volumes, and the core has focused on robust automated brain segmentation and volumetric methods. Machine-learning based brain segmentation tool for 3T (Classification using DErivative-based Features or C-DEF) and transfer-learning based tool for 7T (Pseudo-Label Assisted nnU-net based segmentation) have been developed in-house and are being used to analyze volumetric neurological disorders such as multiple sclerosis (MS), people living with HIV (PLWH), and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) in comparison with matched control subjects. In addition, conventional brain segmentation algorithms such as FreeSurfer are used for finer parcellations in studies such as long-term effects in the brain of people who have recovered from COVID-19 infections. - Imaging of postmortem human tissue: We have previously developed high-resolution imaging techniques for the postmortem fixed brain, and efficiently targeting pathological tissue using individualized, 3D-printed cutting box. These are widely used in collaborative projects, including for cataloging lesion from brain donated to the National Multiple Sclerosis Brain Bank. We have extended these postmortem imaging techniques to study the spinal cord in various neurological disorders such as MS and amyotrophic lateral sclerosis. The core continues its collaborative work on MR-Microscopy (imaging at finer than 100-micron isotropic resolution) in various regions of the human brain to better understand the cytoarchitectural contributions to MRI contrast, as well as imaging of (un-fixed) tissue frozen at the time of autopsy. - Improving coil combination and quantitative susceptibility mapping (QSM): qMRI core is evaluating coil combination strategies with the goal of improving accuracy and reliability of QSM in highly accelerated scans. Such measures will be evaluated as imaging markers of disability in diseases. - In-vivo spinal cord imaging: The core has previously developed high resolution spinal cord imaging techniques at 3T and 7T. In collaboration with researchers at University of Florence, we have found that spinal cord cross-sectional area at the time of hematopoietic stem cell transplantation in multiple sclerosis patients is a promising marker for treatment outcome. - In-vivo imaging at ultra-low fields: Core is involved with developing and applying imaging techniques on the ultra-low field MRI scanners, including better visualization of MRI contrast agent (CA) and improving imaging resolution of routine sequences. We are also working closely with other NINDS groups to evaluate MRI-contrast enhancement in various neurological diseases and stroke.