[Study of optic radiations in patients with primary open-angle glaucoma with diffusion tensor imaging]

Area of Science:

• Neuroscience
• Ophthalmology
• Medical Imaging

Background:

• Primary open-angle glaucoma (POAG) is a leading cause of irreversible blindness.
• Optic nerve damage in POAG is well-documented, but alterations in the optic radiations are less understood.
• Diffusion tensor imaging (DTI) offers a method to assess white matter integrity non-invasively.

Purpose of the Study:

• To investigate microstructural changes in the optic radiations of POAG patients using DTI and tractography.
• To correlate DTI-derived parameters with the clinical severity of POAG.

Main Methods:

• DTI and tractography were performed on 24 POAG patients and 20 healthy controls.
• Key DTI parameters measured included fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD).
• Disease severity was assessed using the Hodapp-Anderson-Parrish (HAP) system, with bilateral eye stages summed.

Main Results:

• POAG patients exhibited significantly reduced FA and AD, and increased RD in the optic radiations compared to controls.
• No significant difference in MD was observed between groups.
• FA showed a negative correlation with POAG severity, while RD and MD demonstrated positive correlations.

Conclusions:

• DTI reveals significant microstructural alterations in the optic radiations of POAG patients, indicating compromised fiber integrity.
• Changes in FA, RD, and MD are associated with the severity of primary open-angle glaucoma.
• DTI may serve as a valuable tool for assessing optic radiation damage in POAG.