In Moderate and Advanced Glaucoma, Structural Imaging Accompanies Acuity Loss

Physicians may be able to determine the risk for impaired visual acuity (VA) based on optical coherence tomography angiography (OCT-A) in patients with moderate to advanced glaucoma, according to a study published in British Journal of Ophthalmology. These findings could help clinicians identify patients at risk for visual impairment and reduced quality of life. 

In this cross-sectional study, participants from the Diagnostic Innovation in Glaucoma Study underwent eye exams and researchers collected patient demographics to explore the association between macular OCT/OCT-A parameters and visual acuities in eyes with different severities of glaucomatous damage. Spectral domain OCT and OCT-A were performed on all patients. Macular vessel density (VD), ganglion cell complex (GCC) thickness and foveal avascular zone (FAZ) were parameters measured.  

A total of 114 eyes of 100 participants were included in the study. Eyes were divided into 2 groups: the early glaucoma group (mean age, 78.7 years [76.7-80.6]) and moderate-advanced glaucoma (mean age, 79.8 years [77.8–81.7]). Patients in the moderate-advanced group had worse VA compared with the early group and a greater percentage of eyes in the moderate-advanced group (38%) had a decreased VA (P =.003). 

OCT/OCT-A parameters were not associated with logMAR VA in the early glaucoma group (P >.05 for all). However, for the moderate-advanced glaucoma group, greater FAZ area (β=0.023 [0.002 – 0.043]; P =.035), and lower superior hemifield periVD (β=0.007 [0 – 0.014]; P =.045) was associated with lower logMAR VA. 

“This study investigated the relationship between macular OCT and OCT-A structural parameters with VA across different glaucoma severities. For early glaucoma eyes, none of the parameters were associated with VA. However, in moderate-advanced glaucoma eyes, lower values of most GCC thickness parameters were associated with worse VA,” the researchers explain. “In contrast, most VD parameters were not significantly associated with VA.”

The primary limitation of the study was that VD measurements are more variable than OCT thickness measurements. A limited number of eyes also meant that detail severity analysis was unable to be performed.