Progressive peripapillary capillary vessel density loss and long-term visual field progression in Normal tension...

Area of Science:

• Ophthalmology
• Glaucoma Research
• Retinal Imaging

Background:

• Normal tension glaucoma (NTG) is a progressive optic neuropathy characterized by visual field (VF) impairment.
• Peripapillary capillary vessel density (pcVD) is a key indicator of retinal microvasculature health.
• Understanding the relationship between microvascular changes and VF loss is crucial for managing NTG.

Purpose of the Study:

• To investigate the association between the rate of peripapillary capillary vessel density (pcVD) reduction and the progression of visual field (VF) defects in individuals with normal tension glaucoma (NTG).

Main Methods:

• A prospective cohort study involving 110 participants with NTG.
• Visual field defects were assessed using standard automated perimetry (mean deviation - MD).
• Peripapillary capillary vessel density (pcVD) was measured using optical coherence tomography angiography.
• Linear mixed-effects models analyzed changes in pcVD and VF MD over time.

Main Results:

• 30% of participants exhibited fast visual field progression (MD slope steeper than -0.5 dB/year).
• Patients with VF progression showed a significantly faster rate of pcVD reduction compared to those with stable or slow progression (-0.73%/year vs. -0.56%/year, p=0.022).
• The rate of pcVD reduction positively correlated with the rate of VF MD decline (p=0.001).

Conclusions:

• Faster progression of visual field impairment in NTG is linked to a more rapid decrease in peripapillary capillary vessel density.
• This finding suggests a significant correlation between microvascular deterioration (pcVD decline) and functional vision loss in NTG.