Differentiation of glaucomatous optic discs with different appearances using optic disc topography parameters: The...

Area of Science:

• Ophthalmology
• Medical Imaging
• Glaucoma Research

Background:

• Glaucomatous optic disc morphology is crucial for diagnosing and managing glaucoma.
• Existing methods for classifying optic disc appearances can be subjective.
• The Glaucoma Stereo Analysis Study (GSAS) aimed to objectively characterize these morphologies.

Purpose of the Study:

• To establish predictive formulas for different glaucomatous optic disc appearances using stereo fundus camera data.
• To identify key topographic parameters that differentiate these appearances.
• To provide a novel quantitative method for describing glaucomatous optic disc characteristics.

Main Methods:

• Utilized the GSAS dataset of 187 eyes with primary open-angle glaucoma.
• Applied discrimination analyses with a stepwise forward-selection method on 38 optic disc parameters.
• Selected six key parameters: rim-disc ratios, cup depth, height variation contour, disc tilt, and rim decentering.

Main Results:

• Developed classification formulas for focal ischemic (FI), generalized enlargement (GE), myopic glaucomatous (MY), and senile sclerotic (SS) optic disc types.
• Achieved high areas under the receiver operating characteristic curves (0.86–0.93) for predicting these types.
• Identified significant differences in age, visual acuity, refractive error, glaucoma type, and intraocular pressure among the four disc types.

Conclusions:

• The established GSAS formulas accurately predict and quantify components of different glaucomatous optic disc appearances.
• These formulas offer a novel, objective parameter for describing glaucomatous optic disc characteristics.
• The identified optic disc types represent distinct clinical glaucoma phenotypes.