Dynamic diffusion tensor imaging of spinal cord contusion: A canine model

Area of Science:

• Neuroscience
• Radiology
• Veterinary Medicine

Background:

• Spinal cord contusion (SCI) causes significant neurological deficits.
• Understanding the dynamic changes post-injury is crucial for developing effective treatments.
• Diffusion Tensor Imaging (DTI) offers a non-invasive method to assess white matter integrity.

Purpose of the Study:

• To investigate the dynamic changes in spinal cord contusion using DTI in a canine model.
• To correlate DTI parameters with histopathological findings over time.
• To evaluate DTI's utility in assessing edema, hemorrhage, and axonal damage.

Main Methods:

• A canine model of spinal cord contusion was established using a weight-drop device.
• DTI was performed using a 3.0T MRI scanner at multiple time points post-injury (3h, 24h, 6 weeks, 12 weeks).
• Immunohistochemical analysis (GFAP, NF) was conducted on tissue sections.

Main Results:

• Fractional anisotropy (FA) decreased, while apparent diffusion coefficient (ADC), mean diffusivity (MD), and radial diffusivity (RD) increased at the lesion epicenter.
• Both site and time significantly affected DTI parameters (ADC, FA).
• Histology confirmed reactive astrogliosis, axonal damage, cavity formation, and glial scarring.

Conclusions:

• DTI is a sensitive tool for non-invasively assessing structural changes in spinal cord contusion.
• DTI parameters dynamically change post-injury, reflecting edema, hemorrhage, and tissue reconstruction.
• The study highlights the utility of DTI in monitoring spinal cord injury progression and recovery in a canine model.