Acircularity and Circularity Indexes of the Foveal Avascular Zone in High Myopia

Abstract

We explored the association between foveal avascular zone (FAZ) parameters and high myopia using optical coherence tomography angiography (OCTA). To evaluate the specific influence of high myopia on the FAZ, we divided 106 eyes of 106 patients into quartiles based on the axial length. The upper quartile was then defined as the high myopia group (n = 27), while the lower quartile was the non-high myopia group (n = 26). The FAZ parameters of these two groups were then retrospectively compared to investigate variations in FAZ size and morphology. The mean axial length and spherical equivalent were 23.96 ± 0.94 mm and -2.27 ± 1.58 diopters in the non-high myopia group and 27.42 ± 0.36 mm and -8.12 ± 2.14 diopters in the high myopia group, respectively. The areas of superficial and deep FAZ, perimeters of deep FAZ, major axis lengths of deep FAZ, minor axis lengths of superficial and deep FAZ were significantly larger in eyes with high myopia than in eyes with non-high myopia (P < 0.05). Linear regression analyses showed that no significant correlation was observed between FAZ areas and acircularity and circularity index of FAZ in non-high myopia group, conversely, FAZ areas strongly correlated with acircularity and circularity index of FAZ in high myopia group. We found that An increase in the FAZ area in highly myopic eyes was accompanied by a significant variation in FAZ acircularity and circularity indexes. Further research should address whether these findings are associated with future disease development in highly myopic eyes.

Various configuration types of the foveal avascular zone with related factors in normal Chinese adults with or without myopia assessed by swept-source OCT angiography

“…Additionally, FAZ area had an increasing trend with myopia severity. Previous studies have also shown that FAZ area was significantly enlarged in highly myopic eyes than in those with non-high myopia [32][33] . All myopic eyes exhibited thicker CRT and thinner CCT compared with that of emmetropic eyes.…”

Exploration of abnormal dynamic spontaneous brain activity in patients with high myopia via dynamic regional homogeneity analysis

“…The high prevalence of myopia leads to an increased incidence of HM because of the relationship between these two diseases (Morgan et al, 2018). Excessive axial elongation is the most important pathological change in patients with HM; it can cause retinal detachment, choroidal neovascularization, macular hemorrhage, and retinal ischemia, all of which lead to impaired visual function (Piao et al, 2021). In clinical practice, resting-state functional magnetic resonance imaging (rs-fMRI) has recently received considerable attention.…”

Enhanced Apoptosis in Choroidal Tissues in Lens-Induced Myopia Guinea Pigs by Activating the RASA1 Signaling Pathway

“…However, the pathogenesis of myopia remains unclear. 10 The choroid is a subretinal layer of the retina that can provide metabolic support for the retinal pigment epithelium, provide blood supply for the outer retina, and participate in lymphatic drainage. 11 Currently, we recognize that the choroid is a five-layered structure consisting (from the outside to the inside) of the basement membrane of the choriocapillaris, outer collagenous zone, elastic layer, inner collagenous zone, and basement membrane of the retinal pigment epithelium.…”