Color Doppler imaging in untreated high- and normal-pressure open-angle glaucoma

Area of Science:

• Ophthalmology
• Vascular Biology
• Glaucoma Research

Background:

• Glaucoma, including primary open-angle glaucoma (POAG) and normal pressure glaucoma (NPG), is a leading cause of irreversible blindness.
• Ocular blood flow is increasingly recognized as a significant factor in glaucoma pathogenesis.
• Understanding hemodynamic alterations may offer new diagnostic and therapeutic targets.

Purpose of the Study:

• To investigate and compare ocular blood flow velocity indices in untreated patients with POAG and NPG.
• To identify specific vascular patterns associated with each glaucoma subtype compared to healthy controls.

Main Methods:

• Color Doppler imaging was used to measure blood flow velocity in the central retinal and ophthalmic arteries.
• Participants included untreated patients with NPG (n=25), untreated patients with POAG (n=23), and age-matched normal controls (n=26).
• Exclusion criteria included systemic beta-blocker or calcium channel blocker use; statistical analysis involved ANOVA and t-tests with Bonferroni correction.

Main Results:

• Patients with POAG had significantly lower end-diastolic velocity in the central retinal artery compared to normal subjects.
• Ophthalmic artery peak systolic velocity was significantly higher in POAG patients versus NPG and normal subjects.
• Increased resistance indices were observed in both ophthalmic and central retinal arteries in POAG patients, and in the central retinal artery of NPG patients compared to controls.

Conclusions:

• Untreated POAG and NPG demonstrate increased resistance to blood flow within ocular arteries.
• Elevated ophthalmic artery peak systolic velocity is noted in POAG.
• Altered ocular circulation, with distinct presentations, is a common characteristic of both NPG and POAG.