Engineering Commons^™

Optimizing Filter-Probe Diffusion Weighting In The Rat Spinal Cord For Human Translation, Matthew D. Budde, Nathan P. Skinner, L. Tugan Muftuler, Brian D. Schmit, Shekar N. Kurpad

Biomedical Engineering Faculty Research and Publications

No abstract provided.

Rapid In Vivo Detection Of Rat Spinal Cord Injury With Double-Diffusion-Encoded Magnetic Resonance Spectroscopy, Nathan P. Skinner, Shekar N. Kurpad, Brian D. Schmit, L. Tugan Muftuler, Matthew D. Budde

Biomedical Engineering Faculty Research and Publications

Purpose

Diffusion-weighted imaging is a common experimental tool for evaluating spinal cord injury (SCI), yet it suffers from complications that decrease its clinical effectiveness. The most commonly used technique, diffusion tensor imaging (DTI), is often confounded by effects of edema accompanying acute SCI, limiting its sensitivity to the important functional status marker of axonal integrity. The purpose of this study is to introduce a novel diffusion-acquisition method with the goal of overcoming these limitations.

Methods

A double diffusion encoding (DDE) pulse sequence was implemented with a diffusion-weighted filter orthogonal to the spinal cord for suppressing nonneural signals prior to diffusion …

Diffusion Tensor Imaging Correlates With Short-Term Myelopathy Outcome In Patients With Cervical Spondylotic Myelopathy, Aditya Vedantam, Avinash Rao, Shekar N. Kurpad, Michael B. Jirjis, Gerald Eckardt, Brian D. Schmit, Marjorie C. Wang

Biomedical Engineering Faculty Research and Publications

Objective

To determine if spinal cord diffusion tensor imaging indexes correlate with short-term clinical outcome in patients undergoing elective cervical spine surgery for cervical spondylotic myelopathy (CSM).

Methods

A prospective consecutive cohort study was performed in patients undergoing elective cervical spine surgery for CSM. After obtaining informed consent, patients with CSM underwent preoperative T2-weighted magnetic resonance imaging and diffusion tensor imaging of the cervical spine. Fractional anisotropy (FA) values at the level of maximum cord compression and at the noncompressed C1-2 level were calculated on axial images. We recorded the modified Japanese Orthopaedic Association (mJOA) scale, Neck Disability Index, and …

Detection Of Acute Nervous System Injury With Advanced Diffusion-Weighted Mri: A Simulation And Sensitivity Analysis, Nathan P. Skinner, Shekar N. Kurpad, Brian Schmit, Matthew D. Budde

Biomedical Engineering Faculty Research and Publications

Diffusion-weighted imaging (DWI) is a powerful tool to investigate the microscopic structure of the central nervous system (CNS). Diffusion tensor imaging (DTI), a common model of the DWI signal, has a demonstrated sensitivity to detect microscopic changes as a result of injury or disease. However, DTI and other similar models have inherent limitations that reduce their specificity for certain pathological features, particularly in tissues with complex fiber arrangements. Methods such as double pulsed field gradient (dPFG) and q-vector magic angle spinning (qMAS) have been proposed to specifically probe the underlying microscopic anisotropy without interference from the macroscopic tissue organization. …

Clinical Correlates Of High Cervical Fractional Anisotropy In Acute Cervical Spinal Cord Injury, Aditya Vedantam, Gerald Eckardt, Marjorie C. Wang, Brian D. Schmit, Shekar N. Kurpad

Biomedical Engineering Faculty Research and Publications

Objective: Fractional anisotropy (FA) of the high cervical cord (C1-C2), rostral to the injury site, correlates with upper limb function in patients with chronic cervical spinal cord injury (SCI). In acute cervical SCI, this relationship has not been investigated. The objective of this study was to identify functional correlates of FA of the high cervical cord in a series of patients with acute cervical SCI.

Methods: Traumatic cervical SCI patients who underwent presurgical cervical spine diffusion tensor imaging at our institution were reviewed for this study. FA of the whole cord as well as the lateralcorticospinal tracts (CSTs) was calculated …

Diffusion Imaging In The Rat Cervical Spinal Cord, Elizabeth Zakszewski, Brian D. Schmit, Shekar N. Kurpad, Matthew D. Budde

Biomedical Engineering Faculty Research and Publications

Magnetic resonance imaging (MRI) is the state of the art approach for assessing the status of the spinal cord noninvasively, and can be used as a diagnostic and prognostic tool in cases of disease or injury. Diffusion weighted imaging (DWI), is sensitive to the thermal motion of water molecules and allows for inferences of tissue microstructure. This report describes a protocol to acquire and analyze DWI of the rat cervical spinal cord on a small-bore animal system. It demonstrates an imaging setup for the live anesthetized animal and recommends a DWI acquisition protocol for high-quality imaging, which includes stabilization of …

Diffusion Tensor Imaging Of The Spinal Cord: Insights From Animal And Human Studies, Aditya Vedantam, Michael B. Jirjis, Brian D. Schmit, Marjorie C. Wang, John L. Ulmer, Shekar N. Kurpad

Biomedical Engineering Faculty Research and Publications

Diffusion tensor imaging (DTI) provides a measure of the directional diffusion of water molecules in tissues. The measurement of DTI indexes within the spinal cord provides a quantitative assessment of neural damage in various spinal cord pathologies. DTI studies in animal models of spinal cord injury indicate that DTI is a reliable imaging technique with important histological and functional correlates. These studies demonstrate that DTI is a noninvasive marker of microstructural change within the spinal cord. In human studies, spinal cord DTI shows definite changes in subjects with acute and chronic spinal cord injury, as well as cervical spondylotic myelopathy. …

White Matter Structural Connectivity Is Associated With Sensorimotor Function In Stroke Survivors, Benjamin Kalinosky, Sheila M. Schindler-Ivens, Brian D. Schmit

Biomedical Engineering Faculty Research and Publications

Purpose

Diffusion tensor imaging (DTI) provides functionally relevant information about white matter structure. Local anatomical connectivity information combined with fractional anisotropy (FA) and mean diffusivity (MD) may predict functional outcomes in stroke survivors. Imaging methods for predicting functional outcomes in stroke survivors are not well established. This work uses DTI to objectively assess the effects of a stroke lesion on white matter structure and sensorimotor function.

Methods

A voxel-based approach is introduced to assess a stroke lesion's global impact on motor function. Anatomical T1-weighted and diffusion tensor images of the brain were acquired for nineteen subjects (10 post-stroke and 9 …

Diffusion Tensor Imaging And Tractography In Brown-Sequard Syndrome, A. Vendatam, Michael B. Jirjis, Brian D. Schmit, M. D. Budde, J. L. Ulmer, Mei Wang, S. N. Kurpad

Biomedical Engineering Faculty Research and Publications

This report illustrates the utility of DTI and DTT in delineating regions of cord injury in two patients with traumatic Brown-Sequard syndrome. Our results indicate that DTI provides clinically relevant information that supplements conventional MR imaging for patients with acute SCI.