Ophthalmic artery Doppler waveform changes associated with increased damage in glaucoma patients

Area of Science:

• Ophthalmology
• Vascular Biology
• Medical Imaging

Background:

• Primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) are leading causes of irreversible blindness.
• Understanding the vascular contributions to glaucoma pathogenesis is crucial for developing novel therapeutic strategies.

Purpose of the Study:

• To characterize Doppler waveform variables, specifically early systolic acceleration (ESA) and systolic/diastolic mean velocity ratios (Sm/Dm), of the Ophthalmic Artery (OA) using color Doppler imaging (CDI).
• To investigate these parameters in eyes with POAG, NTG, and healthy controls.

Main Methods:

• Color Doppler imaging (CDI) examinations of retrobulbar circulation were analyzed in patients with POAG (n=102), NTG (n=89), and healthy controls (n=59).
• Statistical analyses included one-way ANOVA, chi-square, and Spearman's rank correlation tests to compare groups and explore associations between variables.

Main Results:

• Glaucoma groups exhibited a rightward shift in Doppler waveforms, with significantly lower Sm/Dm ratios compared to controls (P=0.01).
• Early systolic acceleration (ESA) was significantly reduced in both POAG and NTG groups compared to healthy controls (P=0.03).
• Waveform parameters correlated with systemic blood pressure, and Sm/Dm ratios showed negative correlations with visual field defects and retinal nerve fiber layer thickness in glaucoma patients.

Conclusions:

• Blood flow velocity patterns in the Ophthalmic Artery are altered in glaucoma patients throughout the cardiac cycle.
• Further research into the impact of systemic blood pressure on Ophthalmic Artery waveform variables in glaucoma may elucidate underlying vascular dysfunction.