Title

Rapid In Vivo Detection of Rat Spinal Cord Injury With Double-Diffusion-Encoded Magnetic Resonance Spectroscopy

Document Type

Article

Language

eng

Publication Date

4-2017

Publisher

Wiley

Source Publication

Magnetic Resonance in Medicine

Source ISSN

0740-3194

Abstract

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 weighting parallel to the cord. A point-resolved spectroscopy readout (DDE-PRESS) was used for improved sensitivity and compared with DTI in a rat model of SCI with varying injury severities.

Results

The DDE-PRESS parameter, restricted fraction, showed a strong relationship with injury severity (P < 0.001, R2 = 0.67). Although the whole-cord averaged DTI parameter values exhibited only minor injury relationships, a weighted region of interest (ROI) based DTI analysis improved sensitivity to injury (P < 0.001, R2 = 0.66).

Conclusions

In a rat model of SCI, DDE-PRESS demonstrated high sensitivity to injury with substantial decreases in acquisition time and data processing. This method shows promise for application in rapid evaluation of SCI severity. Magn Reson Med, 2016. © 2016 Wiley Periodicals, Inc.

Comments

Magnetic Resonance in Medicine, Vol. 77, No. 4, (April 2017): 1639-1649. DOI.