Interpreting the structure-function relationship in high myopia-associated glaucoma: A review

Visual field (VF) interpretation in high myopia-associated glaucoma (HMG) is challenging due to frequent structure-function discordance and coexisting myopia-related changes. These changes may reduce the reliability of conventional structure-function mapping and increase the risk of misclassifying non-glaucomatous VF abnormalities as glaucomatous damage. This narrative review summarizes characteristic VF patterns and imaging findings in highly myopic eyes with and without glaucoma and discusses limitations relevant to clinical interpretation. We identify that (i) highly myopic eyes without glaucoma commonly show atypical VF defects, including enlarged blind spots and mixed temporal-nasal losses, which may progress; (ii) highly myopic eyes with glaucoma frequently demonstrate early central and paracentral VF involvement; (iii) novel OCT and OCT angiography biomarkers may show closer associations with glaucoma progression in highly myopic eyes than refractive status alone; (iv) macular OCT parameters, particularly GCIPL and GCC thickness from cube scans or RNFL thickness from vertical fovea-centred raster scans, may provide more reliable structure-function correspondence than peripapillary RNFL measurements. However, structure-function interpretation in high myopia may be confounded by co-existing high myopia-related non-glaucomatous optic neuropathy, myopic maculopathy, blind spot enlargement due to the secondarily enlarged optic disc, marked parapapillary beta and gamma zones, and imaging artefacts. Recognition of these limitations and adoption of tailored strategies are essential for optimizing clinical management of high myopia-associated glaucoma.