Angle closure glaucoma detection using fractal dimension index on SS-OCT images

Area of Science:

• Ophthalmology
• Medical Imaging
• Biomedical Engineering

Background:

• Angle closure glaucoma (ACG) is a significant cause of vision loss.
• Accurate and non-invasive assessment of the anterior chamber angle is crucial for ACG diagnosis.
• Optical coherence tomography (OCT) offers high-resolution, non-invasive imaging of ocular structures.

Purpose of the Study:

• To develop an automatic, landmark-invariant method for quantifying the anterior chamber angle using SS-OCT.
• To evaluate the efficacy of fractal dimension (FD) analysis in characterizing angle structures.
• To assess the potential of FD index for classifying open angle and angle closure glaucoma.

Main Methods:

• Analysis of 708 SS-OCT images from 148 patients.
• Application of fractal dimension (FD) analysis to quantify the complexity of the angle recess.
• Evaluation of the FD index against biometric parameters for glaucoma classification.

Main Results:

• The fractal dimension index provided a distinct measurement for open (average FD: 1.944 ± 0.045) and closed angle glaucoma (average FD: 1.894 ± 0.043).
• FD analysis effectively captured angle configuration dynamics in different glaucoma types.
• The proposed method demonstrated promising results in differentiating between open and closed angles.

Conclusions:

• Fractal dimension analysis is a viable method for quantifying anterior chamber angle complexity from SS-OCT images.
• The developed FD index shows potential as a diagnostic biomarker for angle closure glaucoma.
• This approach could lead to a computer-aided diagnostic tool for ACG, improving early detection and management.