Scoping literature review: Comparing MRI tractography methods for optic radiation analysis

Area of Science:

• Neuroimaging
• Radiology
• Neurosurgery

Background:

• Accurate mapping of optic radiations (ORs) is vital for preventing visual field deficits in temporal lobe surgery.
• Traditional DTI-based tractography methods have limitations in delineating the complex ORs, especially Meyer's loop.

Purpose of the Study:

• To review and compare DTI-based deterministic and probabilistic tractography methods for delineating the ORs.
• To identify the most accurate and reliable tractography method for mapping the ORs, focusing on Meyer's loop.

Main Methods:

• Systematic literature review following PRISMA guidelines.
• Inclusion of 12 studies comparing deterministic and probabilistic tractography for OR delineation.
• Analysis of methods focusing on anatomical accuracy and preservation of tract curvature.

Main Results:

• Low-threshold probabilistic tractography (≤1%) demonstrated superior anatomical accuracy for OR delineation compared to traditional methods.
• Probabilistic tractography accurately mapped Meyer's loop anterior border and preserved its curved trajectory.
• Emerging deterministic techniques like ACT, MAGNET, and parallel transport tractography show improved OR mapping capabilities.

Conclusions:

• Low-threshold probabilistic tractography is the most accurate method for OR delineation but has high computational costs.
• Advanced deterministic tractography methods offer promising, clinically applicable alternatives for OR mapping.
• Tailored tractography protocols are needed to address the anatomical complexity of the ORs.