Faster vessel density loss during an initial follow-up period of approximately 2 years appears to be associated with faster concurrent and subsequent rates of visual field loss during an extended follow-up period in patients with primary open-angle glaucoma or suspected of having glaucoma, according to findings published in JAMA Ophthalmology.
To evaluate the association between the rate of initial vessel density loss and subsequent visual field loss, the investigators conducted a retrospective cohort study. They assessed the eyes of patients with primary open-angle glaucoma (POAG) as well as glaucoma suspects for a mean of 4.0 years between January 1, 2015, and February 29, 2020.
Patients underwent optical coherence tomography angiography (OCT-A) and spectral domain OCT imaging simultaneously. Researchers considered 2 main study outcomes; the rate of vessel density loss — derived from macular whole-image vessel density values from 3 OCT-A scans early during the study — and the rate of visual field loss, calculated from visual field mean deviation during the entire follow-up period after the first OCT-A visit. Statistical models were used to estimate rates of change.
The study included 124 eyes from 82 patients (mean age, 69.2±10.9 years; 50.0% women, 50.0% men). At a mean initial follow-up period of 2.1 years (95% CI, 1.9 to 2.3), the annual rate of vessel density change was -0.80% (95% CI, -0.88 to -0.72%). The investigators categorized eyes with annual rates of vessel density loss of -0.75% or greater (n=62) as fast OCT-A progressors and those with annual rates of less than -0.75% (n=62) as slow OCT-A progressors.
The annual rate of visual field loss was -0.15 dB (95% CI, -0.29 to -0.01 dB) among slow OCTA progressors and -0.43 dB (95% CI, -0.58 to -0.29 dB) among fast OCTA progressors (difference, -0.28 dB; 95% CI, -0.48 to -0.08; P =.006). In a multivariable model adjusting for concurrent visual field mean deviation rate, the fast OCT-A progressor group was associated with a faster overall rate of visual field loss (-0.17 dB; 95% CI, -0.33 to -0.01 dB; P =.04).
The study suggests that using OCT-A to assess VD loss may provide insight into the VF mean deviation loss. Researchers also report that it is the first to examine the association between the rate of initial VD loss during a given period and subsequent rate of VF progression.
Limitations of the study included only 3 OCTA/OCT 3×3 mm2 scans to determine the progressor group, varying stages of disease among the patients at their initial visit, lack of consideration of minor causes of visual field loss, the retrospective study design and inability to exclude the possibility of bias associated with data selection, potential residual confounding factors, and a relatively small sample size. The investigators also noted that the study included many eyes with early glaucoma, which may limit extrapolation of the results to eyes with moderate to severe stages of glaucoma.
Disclosure: Some study authors declared affiliations with the biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Nishida T, Moghimi S, Wu JH, et al. Association of initial optical coherence tomography angiography vessel density loss with faster visual field loss in glaucoma. JAMA Ophthalmol. Published online February 24 2022. doi:10.1001/jamaophthalmol.2021.6433