Measuring optic nerve head perfusion to monitor glaucoma: a study on structure-function relationships using laser...

Area of Science:

• Ophthalmology
• Glaucoma Research
• Medical Imaging

Background:

• Open-angle glaucoma (OAG) is a progressive optic neuropathy characterized by visual field (VF) loss.
• Monitoring glaucoma progression involves assessing neural structure and function.
• Current methods like optical coherence tomography (OCT) may have limitations in detecting changes in advanced disease.

Purpose of the Study:

• To investigate the correlations between visual field sensitivity, optic nerve head (ONH) perfusion (measured by LSFG), and neural structure (measured by OCT) in OAG.
• To compare the floor effect of LSFG and OCT in assessing glaucoma severity.

Main Methods:

• A cross-sectional, multicenter study involving 50 OAG patients and 51 controls.
• Automated perimetry for VF sensitivity, LSFG for ONH perfusion, and OCT for RNFL thickness (RNFLT) and GCIPL thickness (GCIPLT).
• Analysis of global and localized correlations and assessment of floor effects using breakpoint analysis.

Main Results:

• LSFG showed stronger global and localized correlations with VF sensitivity compared to OCT.
• LSFG (Mean All parameter) demonstrated a significant correlation with VF sensitivity (r=0.56, p<0.001) without a breakpoint.
• OCT parameters (RNFLT and GCIPLT) exhibited breakpoints, indicating a floor effect at -8.53 and -4.05 dB, respectively.

Conclusions:

• LSFG demonstrates superior correlation with VF sensitivity, particularly in central visual field sectors, compared to OCT.
• LSFG exhibits a more favorable floor effect than OCT, suggesting its utility in monitoring glaucoma progression, especially in late-stage disease.
• LSFG is a promising tool for glaucoma monitoring, warranting further longitudinal studies.