Differences in Retinal and Choroidal Vasculature and Perfusion Related to Axial Length in Pediatric Anisomyopes

Abstract

The purpose of this study was to evaluate the interocular differences in choroidal vasculature, choriocapillaris perfusion, and retinal microvascular network, and to explore their associations with interocular asymmetry in axial lengths (ALs) in children with anisomyopia. METHODS.Refractive error, AL, and other biometric parameters were measured in 70 children with anisomyopia. Using optical coherence tomography (OCT) and OCTangiography, we measured the submacular choroidal thickness (ChT), total choroidal area (TCA), luminal area (LA), stromal area (SA), choroidal vascularity index (CVI), choriocapillaris flow deficit (CcFD), retinal vessel density (VD), and foveal avascular zone (FAZ) area. RESULTS.The mean interocular differences in spherical equivalent refraction and AL were −2.26 ± 0.94 diopters and 0.95 ± 0.46 mm, respectively. Submacular ChT, TCA, LA, SA, and CVI were all significantly lower in the more myopic (longer AL) eyes than in the less myopic (shorter AL) fellow eyes. In eyes with longer ALs, both the CcFD and FAZ areas were significantly greater, whereas the superficial and deep retinal VDs were significantly less. After adjusting for corneal power and intraocular pressure, interocular differences in LA (β = −0.774), SA (β = −0.991), and CcFD (β = 0.040) were significantly associated with interocular asymmetry in AL (all P < 0.05). CONCLUSIONS.In pediatric anisomyopes, eyes with longer ALs tended to have lower choroidal vascularity and choriocapillaris perfusion than the contralateral eyes with shorter ALs. Longitudinal investigations would be useful follow-ups to test for a causal role of choroidal circulation in human myopia.

Choroidal thickness and choriocapillaris vascular density in myopic anisometropia

“…The vascular density of the choriocapillaris was decreased in more myopic eyes only when there was a variance of more than 1.50 D in the anisometropic participants. The repeatability of the choroidal thickness, vascular density, and flow voids measurements was comparable with other studies [ 25 , 26 ]. The choriocapillaris was defined as the structure located from 9 μm above to 31 μm below Bruch’s membrane, consistent with Al-Sheikh et al’s study [ 21 ], but different from Wu et al’s.…”

“…The latter analyzed the choriocapillaris 20 μm below the Bruch’s membrane. Therefore, the flow voids of the choriocapillaris results in this study are more than Wu et al’s reports [ 25 , 26 ].…”

“…One recent study on anisometropic patients only examined choroidal thickness and did not investigate choriocapillaris changes [ 24 ]. Although other studies have investigated the choriocapillaris in adult and pediatric patients with myopic anisometropia, these studies focused on the choriocapillaris flow voids and other parameters but did not examine choriocapillaris vascular density changes [ 25 , 26 ]. Therefore, our study examined interocular differences in choroidal thickness, vascular density, and flow voids of the choriocapillaris in anisometropic myopes to further explore the relationship between choroidal blood flow and myopia in young patients.…”

Macular Microvasculature Is Associated With Total Cerebral Small Vessel Disease Burden in Recent Single Subcortical Infarction

“…The SS-OCT has a faster scanning speed which allows for denser scan patterns and larger scan areas; also, it has a longer wavelength and its reduced sensitivity roll-off results in enhanced light penetration through the RPE as well as better detection of signals from deeper layers to overcome the barrier of the RPE (Miller et al, 2017 ). Our current study expanded previous studies by clearly defining the choroidal thickness as the distance between Bruch's membrane and the choroid-sclera interface (ie suprachoroid) (Wu et al, 2021 ). These boundaries measure the choroid extending as far as the vessel walls closest to the sclera.…”

Two-year longitudinal change in choroidal and retinal thickness in school-aged myopic children: exploratory analysis of clinical trials for myopia progression

“…Thus, CT changes precede axial length changes and scleral remodelling [ 5 , 7 ]. The change in subfoveal CT could be related to changes in choroidal blood flow [ 8 , 9 ], lymphatics [ 10 ], nonvascular smooth muscle [ 11 ] and choroidal vascularity index [ 12 , 13 ]. Zhou and colleagues found that changes in CT were positively correlated with changes in choroidal blood flow in guinea pig myopia [ 14 ] and increased choroidal blood flow attenuates scleral hypoxia as well as inhibits myopia development [ 15 ].…”