Macular vessel density (VD) loss and ganglion cell complex (GCC) thinning rates may predict visual field (VF) loss and should be monitored during glaucoma progression evaluations, according to research published in Ophthalmology Glaucoma.
Researchers enrolled 95 eyes (37 preperimetric, 58 early glaucoma, mean age 68.3 years, 60% women) from the Diagnostic Innovations in Glaucoma Study (DIGS) (ClinicalTrials.gov Identifier: NCT00221897) in the analysis. They obtained whole image (wiVD and wiGCC) and parafoveal scans via optical coherence tomography (OCT) and OCT-angiography (OCT-A) and examined structure-function (SF) correlations between VD/GCC and central VF measurement change rates. They also scanned localized regions of interest (LROI), whole image hemiretinas, and superior, inferior, temporal and nasal sectors of parafoveal maps.
The team determined that VD loss and GCC thinning were associated with central VF damage. They noted SF correlations of 0.42 (95% CI, 0.24-0.58) between wiVD and 10-2 VF change rates (P <.001) and 0.27 (95% CI, 0.08-0.45) between wiGCC and 10-2 VF change rates (P =.05). Investigators used a linear mixed effect model to estimate wiVD and wiGCC losses of 1.02% and 0.93 µm per year, respectively, which correlated with a central VF loss of 0.14dB/year. They also observed losses in VD rates, central VF, and GCC with the parafoveal map (-0.94%/ year, -0.23 dB/ year, and -0.96 µm/year, respectively).
“Rates of VD loss and GCC thinning were both associated with central VF loss over time,” according to the researchers, “and assessment of both should be considered for monitoring of the disease and evaluation of glaucoma progression.”
Study limitations include the high number of OCT scans excluded for artifacts (approximately 30%) and poor image quality.
Mohammadzadeh V, Moghimi S, Nishida T. Longitudinal structure–function relationship between macular vessel density and thickness and central visual field in early glaucoma. Ophthalmol Glaucoma. Published online June 13, 2022. doi:10.1016/j.ogla.2022.06.004