In a brand new examine, researchers in contrast the orientations of nerve fibers in a human brainstem utilizing two superior imaging methods: diffusion magnetic resonance imaging (dMRI)-based tractography and polarization delicate optical coherence tomography (PS-OCT). The findings might support in combining these methods, which every supply distinctive benefits, to advance our understanding of the mind’s microstructure and assist inform new methods for early prognosis of varied mind problems.
Isabella Aguilera-Cuenca from the College of Arizona will current this analysis at Frontiers in Optics + Laser Science (FiO LS), which can be held 23 – 26 September 2024 on the Colorado Conference Heart in Denver.
Neurodegenerative illnesses have gotten more and more widespread as lifespans enhance and populations age – higher understanding the hyperlink between mind microstructure and these illnesses might result in growing improved strategies for prevention, detection, and administration.”
Isabella Aguilera-Cuenca, College of Arizona
Nerve fiber orientation is a vital facet of mind microstructure as a result of its affect on the connectivity and communication pathways within the mind. One option to examine this microstructure is through the use of dMRI, a non-invasive methodology imaging methodology that makes use of water molecule diffusion to disclose structural connectivity. A specialised utility of dMRI referred to as diffusion tensor imaging (DTI) can be utilized to reconstruct nerve fiber pathways by means of a course of referred to as tractography. Though DTI is delicate to variations throughout mind tissue environments, it will possibly’t detect particular mobile adjustments and might solely resolve nerve tracts, not particular person axon orientations.
PS-OCT can also be helpful for finding out mind microstructure. It makes use of the properties of back-scattered gentle and variations in polarization to create depth-resolved cross-sectional photos of tissue microstructures. This data can be utilized to determine fiber tracts with micrometer-scale decision and distinguish between white and grey matter. Nonetheless, in scattering media resembling mind tissue, PS-OCT can solely picture up to a couple millimeters deep.
To conduct a quantitative comparability of nerve fiber orientation distributions with dMRI-based tractography and PS-OCT, the researchers used each methods to picture a human brainstem pattern mounted in paraformaldehyde after which saved in PBS with sodium azide.
The outcomes confirmed that polarization properties of part retardation and optic axis can be utilized to map nerve fiber presence and orientation in mind tissue, much like outcomes obtained by way of dMRI. This means the robust potential for PS-OCT to validate dMRI information, offering invaluable insights in regards to the microstructural group of nerve fibers, which is essential for understanding regular physiology and the adjustments which will happen with neurodegenerative situations.
“To additional advance this work, we’ll examine the microstructural alterations in a spread of mind areas from sufferers with totally different neurodegenerative situations, with the objective of figuring out alterations that happen with the onset of illness, stated Aguilera-Cuenca. “We hope this work ultimately interprets into new approaches for early detection of those pathologies.”
