Optic Disc Microvasculature Useful in Detecting Glaucoma Progression with Myopia

While all highly myopic eyes had a b-zone, a substantial 19.5% of glaucomatous eyes without high myopia had no b-zone, making it difficult to assess parapapillary microvasculature in eyes without, since signal attenuation from the RPE complicates the detection of reductions. These images (from another study) show optic disc vessel density scan results in two glaucoma patients. Photo: Lee, JY, et al. Sci Rep 13, 1281 (2023). Click image to enlarge.  Visual field (VF) progression is one the primary indicators of worsening glaucoma. However, reduction in optic disc vessel density (ODVD) may possess a helpful association with VF progression in cases of glaucoma with high myopia, researchers highlight in a new study published in Ophthalmology.To examine this possibility, 118 primary open-angle glaucomatous eyes with high myopia and 118 age- and VF-severity-matched eyes with glaucoma but without high myopia were included in the retrospective investigation. With highly myopic eyes, it was found that VF progressors had significantly faster rates of global ODVD reduction than non-progressors (-3.96%/year vs. -1.68%/year). In highly myopic eyes, associated VF progression was linked with younger age (odds ratio [OR] 1.09 per one year younger), higher optic disc hemorrhage prevalence (OR 6.76), thinner baseline retinal nerve fiber layer (RNFL; OR 1.04 per 1µm thinner) and faster rate of global ODVD change (OR 1.63 per 1%/year faster). Rate of average RNFL thinning, however, did not display an association with VF progression in highly myopic eyes. This was not the case for eyes without high myopia, as a significant association with VF progression was seen with faster rate of average RNFL thinning (OR 2.43 per 1mm/year faster) and ODVD change (OR 1.42 per 1%/year faster).Along with the interval for detection of progressive ODVD reduction being around four to five months shorter than for VF progression, the authors of the Ophthalmology paper convey that “these findings indicate that optic disc microvasculature assessment may be an effective method for monitoring glaucoma progression in patients with high myopia.”The reason for this potential, they explain, is due to optic disc vessel density measurements offering particular utility in highly myopic eyes—in which peripapillary RNFL assessment via OCT is often challenging. This challenge comes from a large b-zone beyond the OCT scan circle, which can lead to segmentation errors in RNFL measurements. What’s more, misalignment of the RNFL and OCT scan beam—along with decentering of the scan circle—may occur because of extensive globe elongation. The benefit of using ODVD may also be compounded by the fact that highly myopic eyes tend to have a thinner RNFL than those without, and they can reach a floor effect in the amount of RNFL thinning that can be detected.It is for these reasons that the study authors believe, “given that evaluation of the optic disc microvasculature may be less influenced by the anatomical variations resulting from high myopia than RNFL thickness, [ODVD] offers a potential advantage for detecting glaucoma progression relative to RNFL assessment.”Click here for the journal source. Suh MH, Weinreb RN, Walker E, Zangwill LM. Longitudinal measurement of optic disc vessel density to detect glaucoma progression in high myopia. Ophthalmology. August 4, 2025. [Epub ahead of print].  This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.