Anatomical Characterization of an Optic Disc Notch Using SD-OCT in Glaucoma

Area of Science:

• Ophthalmology
• Medical Imaging

Background:

• Glaucoma is characterized by optic nerve damage.
• Disc notches represent significant neural rim loss.
• Accurate characterization of disc notches is crucial for glaucoma management.

Purpose of the Study:

• To characterize the anatomical dimensions of optic disc notches.
• To utilize novel spectral domain optical coherence tomography (SD-OCT) methods for this characterization.
• To correlate notch dimensions with retinal nerve fiber layer (RNFL) thickness.

Main Methods:

• Retrospective observational study of glaucoma patients with disc notches.
• Enhanced depth imaging using spectral domain optical coherence tomography (SD-OCT).
• ImageJ software used for calculating notch dimensions (height and width).
• Comparison of notch dimensions with quadrant and sectoral RNFL thickness (qRNFLT and sRNFLT).

Main Results:

• Mean notch height was 2.6 mm and mean width was 2.23 mm in 31 eyes.
• RNFL thickness in the notch sector was significantly thinner than adjacent sectors.
• The difference in RNFL thickness was significantly associated with notch height (R² = 20.8, p = 0.01).

Conclusions:

• Automated analysis of disc notch dimensions and RNFL thickness is feasible.
• This method allows for precise glaucoma monitoring in the region of interest.
• SD-OCT provides valuable data for characterizing disc notches and assessing glaucoma progression.