Combining nerve fiber layer parameters to optimize glaucoma diagnosis with optical coherence tomography

Area of Science:

• Ophthalmology
• Medical Imaging
• Glaucoma Diagnostics

Background:

• Glaucoma diagnosis relies on detecting characteristic optic nerve damage.
• Optical coherence tomography (OCT) provides quantitative measurements of the retinal nerve fiber layer (RNFL) thickness.
• Identifying optimal RNFL parameters is crucial for accurate glaucoma detection using OCT.

Purpose of the Study:

• To determine the most effective combination of Stratus OCT RNFL thickness parameters for diagnosing glaucoma.
• To compare the diagnostic performance of various RNFL parameters and their combinations.

Main Methods:

• An observational, cross-sectional study involving 89 participants with and without glaucoma.
• Circumpapillary RNFL thickness was measured using the Zeiss Stratus OCT system.
• Diagnostic performance was evaluated using area under the receiver operating characteristic curve (AROC), sensitivity, and specificity, with RNFL parameters combined using or-logic and and-logic.

Main Results:

• The overall average RNFL thickness showed the highest AROC (0.89) among single parameters.
• The combination of overall, inferior, and superior quadrant RNFL thicknesses achieved the highest AROC (0.92).
• This 3-parameter combination demonstrated significantly better diagnostic performance than the overall average alone (P=0.01).

Conclusions:

• The optimal diagnostic strategy for Stratus OCT RNFL data involves classifying an eye as glaucomatous if the overall, inferior, or superior quadrant RNFL thickness is below normal.
• Combining specific RNFL parameters enhances glaucoma detection accuracy.
• Simpler, focused combinations of RNFL parameters are more effective than complex ones.