Structural Change Can Be Detected in Advanced-Glaucoma Eyes

Area of Science:

• Ophthalmology
• Medical Imaging
• Glaucoma Research

Background:

• Glaucoma is a leading cause of irreversible blindness.
• Early detection of structural changes is crucial for managing glaucoma progression.
• Standard spectral-domain optical coherence tomography (SD-OCT) measures may have limitations in detecting subtle changes in advanced glaucoma.

Purpose of the Study:

• To compare the efficacy of standard SD-OCT structural measures against a novel three-dimensional (3D) volume optic nerve head (ONH) change detection method.
• To assess the ability to detect structural change over time in patients with severely advanced open-angle glaucoma (OAG).

Main Methods:

• Thirty-five eyes of advanced OAG patients and 46 eyes of healthy subjects were analyzed.
• Standard measures included circumpapillary retinal fiber layer (cpRNFL) thickness, minimum rim width (MRW), and macular ganglion cell-inner plexiform layer (GCIPL) thickness.
• A new 3D volume ONH change detection method, Bayesian-kernel detection scheme (BKDS), was employed, requiring less segmentation.

Main Results:

• The 3D volume BKDS identified the most progressing glaucoma eyes (37%), followed by GCIPL (31%), cpRNFL (11%), and MRW (6%).
• In advanced OAG, only GCIPL change rate was statistically significant (-0.18 μm/y, P=0.02).
• Rates of cpRNFL and MRW change were not significantly different from zero in advanced OAG eyes, but were significant in healthy eyes.

Conclusions:

• Both GCIPL thickness and 3D volume BKDS show potential for identifying structural changes in severe glaucoma.
• These methods suggest that structural changes are detectable even in the very advanced stages of the disease.
• Further long-term follow-up is necessary to validate these findings and differentiate true progression from potential false positives.