Feasibility of prefronto-caudate pathway tractography using high resolution diffusion tensor tractography data at 3T

Area of Science:

• Neuroimaging
• Neuroscience
• Diffusion Tensor Imaging (DTI)

Background:

• Mapping human brain frontostriatal pathways is challenging due to limitations in DTI sensitivity, spatial resolution, and signal-to-noise ratio.
• Previous DTI studies faced difficulties with gray matter anisotropy and partial volume averaging, hindering accurate pathway reconstruction.

Purpose of the Study:

• To evaluate the utility of high spatial resolution DTI-based fiber-tractography using Fiber Assignment by Continuous Tracking (FACT) for reconstructing frontostriatal pathways.
• To quantify bilaterally the prefronto-caudo-thalamic connections in the human brain at 3 Tesla (3T).

Main Methods:

• Employed high spatial resolution DTI with FACT at 3T in five healthy right-handed male subjects.
• Reconstructed and quantified bilateral anterior thalamic radiation and prefronto-caudo-thalamic pathways.
• Measured tract volume and diffusion tensor metrics, including fractional anisotropy (FA) and mean diffusivity (D(av)).

Main Results:

• Successfully reconstructed the anterior thalamic radiation and prefronto-caudo-thalamic pathways bilaterally.
• Anterior thalamic radiation showed significantly larger tract volume and FA compared to the prefronto-caudate pathway.
• No significant differences in tract volume or DTI metrics were found between hemispheres for either pathway.

Conclusions:

• High spatial resolution DTI with FACT enables robust reconstruction and quantification of human frontostriatal pathways, including prefronto-caudo-thalamic connections.
• The developed DTI protocol and analysis successfully mapped connectivity between the caudate, thalamus, and prefrontal cortex.
• This method overcomes previous imaging limitations, offering a valuable tool for studying brain connectivity.