MR Diffusion Anisotropy Imaging of Spinal Cord Mechanical Compression and Injury on the Rat Model. In Vivo

Area of Science:

• Neuroscience
• Radiology
• Biomedical Engineering

Background:

• Spinal cord compression (SCC) and injury (SCI) significantly impact neurological function.
• Accurate and timely assessment of SCI is crucial for understanding disease progression and treatment efficacy.
• Magnetic Resonance Diffusion Anisotropy Imaging (MR DAI) offers a non-invasive method to evaluate tissue microstructure.

Purpose of the Study:

• To apply MR DAI for assessing SCC and SCI in a rat model.
• To investigate the time-dependent changes in diffusion parameters following spinal cord injury.
• To correlate MR DAI findings with the pathological changes in white matter (WM) and gray matter (GM).

Main Methods:

• MR DAI was performed on 20 rats at multiple time points (1, 24, 48, 168 hours) post-injury.
• Diffusion gradients were applied parallel and perpendicular to the spine at 4.7 T.
• Diffusion parameters, including longitudinal ADC (lADC), transverse ADC (tADC), and Anisotropy Index (AI), were calculated for WM and GM.

Main Results:

• Laminectomy-induced epidural hematoma led to SCC, decreasing ADC values in both WM and GM.
• SCI in WM resulted in decreased lADC and increased tADC.
• In GM, SCI caused an increase in both lADC and tADC values.

Conclusions:

• MR DAI is effective in assessing spinal cord compression and injury in rats.
• The study demonstrates dynamic changes in water diffusion parameters within the initial days after SCI.
• MR DAI provides valuable insights into the microstructural alterations occurring in the spinal cord following injury.