Microvasculature evaluation of monocular anisometropic amblyopia children by Angio-OCT

doi:10.21203/rs.3.rs-2091435/v1

Background

To compare and assess the choroidal and retinal microstructural vascularity in amblyopic eyes with the fellow eyes in monocular anisometropic amblyopic children using angiography optical coherence tomography (Angio-OCT).

Methods

Twenty-seven children (54 eyes; 5.59 ± 1.08 years old; 59.3% girls) were enrolled in this study. Choroidal thickness (CT) was measured with the use of the enhanced depth imaging mode in Angio-OCT. Parafoveal/peripapillary vascular density indices and the foveal avascular zone (FAZ) size were analyzed by Matlab code programming on Angio-OCT images.

Results

The mean FAZ size of the amblyopic eyes were larger both in superficial and deep capillary plexus layer (SCPL/DCPL). Compared with the contralateral eyes (which were emmetropia), all the vascular density indices of SCPL and DCPL in the parafoveal and peripapillary zones were lower in the amblyopic eyes, however, the difference were insignificant (p > 0.05). No significant decrease was observed in four quadrants analyses of the amblyopic eyes (p > 0.05). Except for the measurement at 2000µm and 1500µm from the fovea in temple, CT in amblyopic eyes were significantly thicken than the fellow eyes (p < 0.05).

Conclusion

Compared with the fellow eyes, the CT of certain areas were thicker in the amblyopic eyes. Though the FAZ size of the amblyopic eyes were obvious larger in SCPL/DCPL layers, the retinal vascular density indices in SCPL/DCPL were lower in amblyopia eyes without statistically difference. Angio-OCT may be an effective way to evaluate the status of the choroidal and retinal vascular system in amblyopic children.

amblyopia

Angio-OCT

vessel density

microvasculature

As the common cause of preventable vision loss in children, amblyopia was defined as poor visual acuity without anatomical changes, accompanied by abnormal color, motion, and contour perception in the affected eye. In children, amblyopia may affect one eye due to anisometropia, strabismus or visual deprivation [1]. When anisometropia exceeded approximately 1D, it began to be associated with amblyopia [2]. Though the pathophysiology of anisometropia amblyopia had not been fully defined, the functional changes involved in its development can occur at many levels of the visual pathway [3]. Researchers found that the lateral geniculate body and the visual cortex may be influenced by amblyopia and the process of amblyopic may involve the choroid and retina [4–6]. However, the results about the microstructural vascularity were inconsistent or contradictory.

Without dye injection, angiography optical coherence tomography (Angio-OCT) is noninvasive and quantifiable in microvascular vessel perfusion of fundus [7–9]. This quantitative assessment technique could sensitively detect retinal vessel minor alteration. We aimed to compare the affected eyes with the fellow eyes in monocular anisometropic amblyopic children and assess the microstructural vascular differences using Angio-OCT in the present study.

Amblyopia patients

Pediatric patients who were diagnosed monocular anisometropic amblyopia were examined by Angio-OCT from April 2019 to July 2020 in Shanghai Children’s Hospital. Full ophthalmologic examinations were preceded in all participants, including refraction (cycloplegic refraction), visual acuity testing, slit-lamp biomicroscopy, and dilated fundus examination. Logarithm of the mean angle of resolution (logMAR) units was used to measure best corrected visual acuity (BCVA) for statistical analyses. Inclusion criteria of the enrolled patients were following: 4–7 years monocular anisometropic amblyopia, an eye was diagnosed amblyopic when the BCVA was ≥ 2 lines worse than the fellow eye (which was emmetropia), without ocular or systemic diseases. Exclusion criteria were as follows: with any ocular disease history or any systemic disease, previous ocular surgery or laser therapy history, use of any systemic medicine in recent six months, with treatment for amblyopia, and with esotropia or exotropia of ≥ 10△.

Retinal and choroidal data

All ocular measurements were performed in the morning (between 9:00 a.m. and 11:00 a.m). The definition of choroidal thickness (CT) was the vertical distance from the retinal pigment epithelium (RPE) outer surface to the scleral inner surface [10–12]. The choroid was measured from subfoveal area to 2000 µm both at the nasal (N2000) and the temporal (T2000) with 500µm intervals by the use of the enhanced depth imaging (EDI) mode in Angio-OCT [10]. An annulus area outside foveal avascular zone (FAZ), which was the central area devoid of vessels, was set as parafoveal area, which the outer diameter was 3-mm and a 1-mm of the inner diameter [13]. The peripapillary area was set as a 700-µm-wide elliptical annulus extending outward from the optic disc demarcation [14, 15]. The vascular density was defined as the occupied vessel lumens percentage in the corresponding segmented areas [15]. We employed Angio-OCT in our study, according to the quantification of its images, to compare the vascular density of retinal network in monocular anisometropic amblyopia children of the two eyes.

Angio-OCT

Angio-OCT images on the parafoveal/peripapillary areas of the observed eyes were captured by Zeiss Cirrus 5000-HD-OCT with pattern 6 mm × 6 mm. Quantitative mensuration of the macular and optic nerve head vessel density indices containing vessel diameter (VD), vascular skeleton/area density (VSD/VAD), index of vessel perimeter (IVP) on the superficial/deep capillary plexus layer (SCPL/DCPL), and the FAZ size were assessed and compared. The boundary from 3 mm beneath the internal limiting membrane to 15 mm beneath the inner plexiform layer to 70 mm beneath the inner plexiform layer were defined the SCPL and the DCPL separately [13]. These indicators were employed to reflect the vascular perfusion not only from the two dimensions but also from the three-dimensional perspective.

Data treatment and statistical analysis

The data analysis algorithm was implemented using Matlab (2021) code programming, which objectively analyzed the acquired data from the digital images of Angio-OCT. The calculative principle of the vascular indices was previously described in detail [16]. All values were represented in the mean ± standard deviation (SD) form. SPSS (Version 23; Chicago, IL, USA) were applied for statistical analyses, and p < 0.05 was defined as statistical significantly difference. The paired sample t test was applied to compare the differences between amblyopic eyes and fellow eyes. To ensure the measurements reproducibility, all subjects were examined more than three times by the same technician.

Amblyopia patients

A total of 27 monocular anisometropic amblyopia pediatric patients (54 eyes, 59.3% girls) were enrolled in this study. Their mean age was 5.59 ± 1.08 (4–7) years old. BCVA (logMAR) of the amblyopic eyes ranged from 0.70 to 0.10 and was significantly lower than the fellow emmetropia eyes (t = 11.15, p < 0.001).

Angio-OCT indices

Compared with the fellow eyes (which were emmetropia), Angio-OCT indices (VD, VAD, VSD, IVP) at the level of the SCPL/DCPL of the parafoveal and peripapillary areas were at low value in the amblyopic eyes (p > 0.05). However, there was no statistically significant difference in the indices between the emmetropia and the amblyopic eyes (p > 0.05) (Table 1). Besides, no obvious decrease in the parafoveal and peripapillary regions was observed in four quadrants analyses of the amblyopic eyes (p > 0.05) (Table 2). Meanwhile, the FAZ was enlarged in SCPL/DCPL of the amblyopic eyes (0.28 ± 0.12 vs 0.26 ± 0.11 in SCPL and 0.68 ± 0.20 vs 0.65 ± 0.18 in DCPL) (Table 1). Except for the measurement at 2000µm and 1500µm from the fovea at the temple (T2000 and T1500), choroidal thickness in amblyopic eyes were significantly thicken than the fellow eye (t_T1000=2.64, t_T500=3.10, t_{subfoveal CT}=3.13, t_N500=2.54, t_N1000=2.55, t_N1500=2.47, t_N2000=2.29, respectively, p < 0.05) (Table 3).

Table 1

The parafoveal and peripapillary vascular parameters on SCPL/DCPL and the FAZ size in Angio-OCT. Without statistically significant different, Angio-OCT indices in the SCPL/DCPL were lower in the amblyopic eyes. The mean FAZ size of the amblyopic eyes was larger in SCPL/DCPL.
SCPL	Parafovea						Peripapillary
SCPL	amblyopia	emmetropia	mean	SD	t	p	amblyopia	emmetropia	mean	SD	t	p
VD	21.04 ± 0.32	21.09 ± 0.33	-0.054	0.413	-0.675	0.506	21.13 ± 0.31	21.21 ± 0.27	-0.073	0.364	-1.046	0.305
VAD	0.54 ± 0.01	0.54 ± 0.01	-0.004	0.011	-1.954	0.062	0.57 ± 0.02	0.57 ± 0.11	-0.002	0.025	-0.498	0.623
VSD	0.15 ± 0.00	0.15 ± 0.00	0.000	0.002	-1.000	0.327	0.16 ± 0.01	0.16 ± 0.00	-0.001	0.007	-0.877	0.388
IVP	0.35 ± 0.01	0.35 ± 0.01	0.000	0.005	0.000	-1.000	0.35 ± 0.00	0.36 ± 0.00	-0.002	0.011	-1.190	0.245
FAZ	0.28 ± 0.12	0.26 ± 0.11	0.018	0.088	1.054	0.302
DCPL	Parafovea						Peripapillary
DCPL	amblyopia	emmetropia	mean	SD	t	p	amblyopia	emmetropia	mean	SD	t	p
VD	19.83 ± 0.34	19.87 ± 0.30	-0.038	0.309	-0.641	0.527	19.79 ± 0.42	19.90 ± 0.41	-0.102	0.483	-1.096	0.283
VAD	0.52 ± 0.01	0.52 ± 0.01	-0.001	0.012	-0.625	0.537	0.51 ± 0.02	0.51 ± 0.01	-0.002	0.025	-0.445	0.660
VSD	0.15 ± 0.00	0.15 ± 0.00	0.000	0.005	-0.372	0.713	0.15 ± 0.01	0.15 ± 0.00	-0.001	0.007	-0.964	0.344
IVP	0.36 ± 0.00	0.36 ± 0.00	-0.001	0.004	-1.000	0.327	0.35 ± 0.01	0.35 ± 0.00	-0.003	0.014	-0.978	0.337
FAZ	0.68 ± 0.20	0.65 ± 0.18	0.030	0.161	0.981	0.336
SCPL/DCPL: superficial/deep capillary plexus layer; FAZ: foveal avascular zone; Angio-OCT: optical coherence tomography angiography; SD: standard deviation; VD: vessel diameter, µm; VAD: vascular area density; VSD: vascular skeleton density; IVP: index of vessel perimeter.
Significant statistical difference, p < 0.05

Table 2

The parafoveal/peripapillary quadrant regions in amblyopia and emmetropia eyes
	Each quadrant of parafoveal region in SCPL						Each quadrant of parafoveal region in DCPL
	amblyopia	emmetropia	mean	SD	t	p	amblyopia	emmetropia	mean	SD	t	p
VD T	21.06 ± 0.51	21.09 ± 0.79	-0.030	1.030	-0.159	0.875	20.39 ± 0.50	20.24 ± 0.53	0.153	0.673	1.179	0.249
VD S	21.047 ± 0.73	21.20 ± 0.70	-0.150	0.940	-0.842	0.408	20.13 ± 0.69	20.26 ± 0.51	-1.341	0.634	-1.099	0.282
VD N	20.93 ± 0.72	20.92 ± 0.83	0.020	1.170	0.074	0.942	20.23 ± 0.59	20.27 ± 0.61	-0.043	0.814	-0.274	0.786
VD I	21.02 ± 0.61	20.99 ± 0.63	0.035	0.829	0.221	0.827	19.96 ± 0.63	20.04 ± 0.60	-0.072	0.762	-0.493	0.626
VAD T	0.53 ± 0.02	0.53 ± 0.02	0.000	0.029	0.000	1.000	0.52 ± 0.02	0.52 ± 0.02	0.003	0.024	0.651	0.521
VAD S	0.54 ± 0.02	0.54 ± 0.02	-0.003	0.026	-0.516	0.610	0.52 ± 0.02	0.53 ± 0.02	-0.007	0.230	-1.168	0.106
VAD N	0.47 ± 0.17	0.53 ± 0.03	-0.058	0.162	-1.871	0.073	0.53 ± 0.02	0.53 ± 0.03	-0.003	0.030	-0.572	0.572
VAD I	0.53 ± 0.02	0.53 ± 0.02	-0.003	0.003	-0.531	0.600	0.52 ± 0.02	0.52 ± 0.03	0.003	0.031	0.428	0.672
VSD T	0.15 ± 0.01	0.15 ± 0.00	0.001	0.007	0.570	0.574	0.15 ± 0.01	0.15 ± 0.01	0.000	0.006	0.296	0.769
VSD S	0.15 ± 0.00	0.15 ± 0.00	0.000	0.005	0.372	0.713	0.16 ± 0.01	0.16 ± 0.01	-0.001	0.007	-1.072	0.294
VSD N	0.15 ± 0.01	0.15 ± 0.01	0.000	0.007	0.000	1.000	0.15 ± 0.01	0.15 ± 0.01	-0.001	0.007	-0.827	0.416
VSD I	0.15 ± 0.01	0.15 ± 0.01	-0.002	0.006	-1.546	0.134	0.16 ± 0.01	0.15 ± 0.01	0.001	0.008	0.721	0.477
IVP T	0.36 ± 0.01	0.36 ± 0.01	0.001	0.009	0.848	0.404	0.36 ± 0.01	0.36 ± 0.01	0.000	0.008	-0.254	0.802
IVP S	0.36 ± 0.01	0.36 ± 0.01	-0.003	0.010	-1.803	0.083	0.37 ± 0.01	0.37 ± 0.01	-0.001	0.008	-0.941	0.355
IVP N	0.36 ± 0.01	0.36 ± 0.01	0.001	0.009	0.848	0.404	0.36 ± 0.01	0.37 ± 0.01	-0.001	0.010	-0.386	0.703
IVP I	0.36 ± 0.01	0.36 ± 0.01	-0.001	0.009	-0.891	0.381	0.37 ± 0.01	0.36 ± 0.01	0.003	0.010	1.317	0.199
	Each quadrant of peripapillary region in SCPL						Each quadrant of peripapillary region in DCPL
	amblyopia	emmetropia	mean	SD	t	p	amblyopia	emmetropia	mean	SD	t	p
VD T	21.75 ± 0.85	21.65 ± 0.61	0.100	0.924	0.560	0.580	20.76 ± 0.74	20.74 ± 0.80	0.022	0.986	0.115	0.909
VD S	21.08 ± 0.42	21.02 ± 0.39	0.061	0.663	0.476	0.638	20.08 ± 0.75	19.84 ± 0.81	0.240	1.080	1.157	0.258
VD N	21.32 ± 0.49	21.39 ± 0.53	-0.077	0.705	-0.568	0.575	20.30 ± 0.74	20.18 ± 0.57	0.125	0.980	0.662	0.514
VD I	21.21 ± 0.65	21.17 ± 0.37	0.041	0.785	0.272	0.788	20.30 ± 1.44	20.24 ± 0.62	0.060	1.527	0.204	0.840
VAD T	0.59 ± 0.04	0.59 ± 0.02	0.000	0.038	0.000	1.000	0.55 ± 0.28	0.55 ± 0.20	0.002	0.030	0.318	0.753
VAD S	0.64 ± 0.03	0.64 ± 0.22	0.001	0.028	0.139	0.891	0.55 ± 0.03	0.54 ± 0.05	0.010	0.056	0.964	0.344
VAD N	0.61 ± 0.03	0.60 ± 0.02	0.002	0.034	0.337	0.739	0.53 ± 0.03	0.53 ± 0.21	0.001	0.034	0.171	0.866
VAD I	0.62 ± 0.04	0.63 ± 0.02	-0.005	0.043	-0.625	0.537	0.54 ± 0.04	0.54 ± 0.03	-0.010	0.034	-1.481	0.151
VSD T	0.16 ± 0.01	0.16 ± 0.01	0.001	0.011	0.348	0.731	0.16 ± 0.01	0.16 ± 0.00	0.001	0.008	0.493	0.626
VSD S	0.18 ± 0.01	0.18 ± 0.01	0.001	0.006	1.000	0.327	0.16 ± 0.01	0.16 ± 0.01	0.001	0.011	0.337	0.739
VSD N	0.17 ± 0.01	0.17 ± 0.01	0.001	0.010	0.402	0.691	0.16 ± 0.01	0.16 ± 0.01	0.000	0.009	-0.205	0.839
VSD I	0.17 ± 0.01	0.17 ± 0.01	-0.003	0.013	-1.302	0.204	0.16 ± 0.01	0.16 ± 0.01	-0.002	0.008	-1.224	0.232
IVP T	0.36 ± 0.01	0.36 ± 0.01	-0.003	0.014	-1.093	0.285	0.36 ± 0.01	0.36 ± 0.01	0.000	0.014	-0.137	0.892
IVP S	0.38 ± 0.01	0.38 ± 0.01	-0.002	0.009	-1.044	0.306	0.37 ± 0.01	0.36 ± 0.02	0.002	0.020	0.490	0.628
IVP N	0.36 ± 0.01	0.36 ± 0.01	-0.001	0.012	-0.311	0.758	0.36 ± 0.01	0.36 ± 0.01	0.000	0.017	0.000	1.000
IVP I	0.37 ± 0.02	0.37 ± 0.01	-0.001	0.014	-0.267	0.791	0.36 ± 0.02	0.36 ± 0.01	-0.004	0.014	-1.462	0.156
SCPL/DCPL: superficial/deep capillary plexus layer; FAZ: foveal avascular zone; SD: standard deviation; VD: vessel diameter, µm; VAD: vascular area density; VSD: vascular skeleton density; IVP: index of vessel perimeter; T: temporal; S: superior; N: nasal; I: inferior.

Table 3

The CT measurement in monocular anisometropic amblyopic eyes and the fellow eyes from T2000 to N2000 at 500µm intervals with EDI in Angio-OCT.
	amblyopia	emmetropia	t	p
T2000	354 ± 68.57	334 ± 69.04	1.47	0.155
T1500	367 ± 66.72	339 ± 65.80	2.05	0.050
T1000	383 ± 67.87	348 ± 71.76	2.64	0.014*
T500	396 ± 70.78	351 ± 76.82	3.10	0.005*
Subfoveal CT	409 ± 78.00	358 ± 84.23	3.13	0.004*
N500	381 ± 77.33	340 ± 85.76	2.54	0.017*
N1000	359 ± 75.00	316 ± 90.89	2.55	0.017*
N1500	338 ± 85.02	294 ± 90.64	2.47	0.020*
N2000	306 ± 95.03	263 ± 87.55	2.29	0.030*
CT: choroidal thickness; T2000: from the fovea to the temple 2000µm; N2000: from the fovea to the nasal 2000µm; EDI: enhanced depth imaging; Angio-OCT: optical coherence tomography angiography.
*significant statistical difference, p < 0.05

To avoid the related risks of indocyanine green and fundus fluorescein angiography, Angio-OCT had often been applied in many reports of children with its noninvasive advantage. We deduced that Angio-OCT could be an effective manner to supervise the microstructural vessel supply in amblyopia pediatric patients.

Though the histopathological evaluation revealed notable cells’ shrinkage and decreased cell sizes in amblyopic eyes, its pathophysiology had not been fully defined. It was considered that the duration of anisometropia was more important than that of strabismus in the development and depth of amblyopia [17]. Anisometropia pediatric patients tended to have more severe amblyopia than strabismus ones [10]. Many researchers had confirmed that the choroidal thickness (CT) in amblyopic eyes was thicker than in the fellow eyes and the normal controls, which was consistent with our results [10]. The choroid provided nutrients to the retinal outer part and blood supply to the optic nerve, which accounted for the majority of the ocular blood flow. In response to adjust the retinal position and promote visual development, the choroid thicknesses became thinner. Studies had shown the choroid played a role in emmetropization and refractive error development [18, 19]. However, this choroidal compensation did not occur in amblyopic eyes [10].

Histologically, SCPL, intermediate capillary plexus layer (ICPL), DCPL and radial peripapillary capillaries layer (RPCL) composed the retinal vascular network. The layers of retinal vasculature occupied and supplied nutrients to the inner half region only. The layers of choriocapillary maintained and provided the outer retina as the primary blood supply source for the photoreceptors. In the macular region, both at the levels of SCPL and DCPL sharply demarcated a ring of FAZ. In the peripapillary region, RPC supply the retinal nerve fiber layer (RNFL). The microvessel changes in the parafoveal/ peripapillary areas may represent the variation that the amblyopic eyes suffered. Recently, after studied 14 amblyopes aged 6 to 12 years, Kaur, S et al found that the VD in choriocapillary attenuated in the amblyopic eye which suggested that the choriocapillary may involve in the amblyopia pathogenesis [20].

Contrast to the choroid, researchers found that amblyopia did not affect retinal thickness [21]. However, fundamental neurological studies showed that the amblyopia development was associated with the variation in retinal microcirculation and function, and these were supported by clinical research [22]. In accordance with many researchers, we found the Angio-OCT indices in the SCPL/DCPL of the parafoveal areas were decreased in amblyopic eyes compared with fellow emmetropia eyes [23–25]. Yilmaz and colleagues hypothesized that the underuse of the amblyopic eyes may induce these retinal or choroid microvasculature alterations [24]. The FAZ, which was sharply surrounded by a capillaries ring demarcating the avascular area, presented both at the levels of SCPL and DCPL in the macular region. We found that the FAZ in the anisometropia amblyopic eyes at the level of SCPL/DCPL were larger than the fellow eyes, which was similarly to Yilmaz’s research. Nevertheless, the results had no statistically significant difference. However, Isa Sobral et al. documented a marginally statistically significant increase in FAZ of DCPL in amblyopic eyes compared with control eyes [25]. Differently, Araki, S and partners’ research showed no significant difference in the macular VD but smaller FAZ area of SCPL was found in the amblyopic eye after magnification error correction [26]. We analyzed that the inconsistence may due to the amblyopic classification and degree, as many previous reports enrolled both the anisometropia and the strabismus amblyopic patients or only with the strabismus amblyopic children. Besides, the small sample and the age of the participants also may lead to the inconsistent. Furthermore, the difference of built-in software algorithm in Angio-OCT should be considered.

Of note, though without significant difference, we observed the vascular perfusion in the parafoveal region and the peripapillary region and found that the vascular indices were decreased in the amblyopic eyes both on the SCPL and DCPL level. Besides, no obvious decrease in the parafoveal and peripapillary regions was observed in four quadrants analyses of the amblyopic eyes (p > 0.05). Until now, we have a small age span range (4–7 years old) and we aim to minimize the age influence on our results. The vessel density parameters reflected the vessel dimension and vascular supply changes at different regions in the fundus. Previous reports showed discrepancy of opinions on the microvascular structure and function. Sobral, I., et al. pointed that not only the microvascular structure changed, but also function dependent parameters were influenced in the macula and the optic nerve in amblyopic children [25]. Unlikely, Cinar E hold the viewpoint that no significant vascular damage was demonstrated by Angio-OCT in amblyopic eyes, which was similar with our results. Although without the statistical difference in our results, we supposed that minor vascular perfusion affected by amblyopia may correlate with macular and the optic disk blood supply. However, how these changes occur and its specific mechanisms are needed to evaluate in future study. Yet, Cinar E indicated specific localized vascular defects were related to amblyopia and pointed that parameters in superior quadrant were lower in amblyopic eyes, which were inconsistent with our findings [27]. We speculate that the inconsistencies between our analysis and the literature may be related to the age distribution of the patients as well as the duration and severity of amblyopia.

There still were some limitations in our present study. We did not categorize subjects by amblyopia severity degree. All the amblyopic children had already undergone occlusion or atropine therapy; however, we did not document the treatment progress. It is believed that CT varied in healthy eyes according to sex, axial length, age and has a diurnal variation. We measured the CT at the same period in the day, without considering other influences. Sobral et al hypothesized that the brain can compensate for the vascular amblyopic deficit when amblyopia was treated [25].We exclude the effects of blood pressure or the diurnal variation influence on retinal and choroidal vessels [28]. We will do more observation and follow-up on these in future research. Moreover, due to the differences in Angio-OCT models and calculation methods, there is no reference value of large sample normal groups in children for comparison. In this sense, the establishment of pediatric Angio-OCT data in normal children is crucial to determine.

Compared with the fellow eyes, the choroidal thickness in certain areas were thicker in the amplyopic eyes. Besides, the retinal and optic disk vascular density indices in the SCPL/DCPL were lower in amblyopia eyes though without statistically difference. Angio-OCT may be an effective method to assess the variation of retinal and choroidal microvascular system.

Statement of Ethics

The research protocol adhered to the tenets of the Declaration of Helsinki and was approved by the Institutional Review Board of the Shanghai Children’s Hospital (2018R013-E02). Written informed consent was obtained from the participants' parent/legal guardian to participate in the study.

Conflict of Interest Statement:

We (all authors) declare that we have no conflict of interest in this manuscript.

Fundings:

This study had no funding.

Author Contributions:

Haiyun Ye wrote the manuscript; Siying Wang, Yidan Zhang and Wangyi Fang contributed significantly to analysis and manuscript preparation; Han Ye performed the data analyses; Luya Chen and Tong Qiao helped perform the analysis with constructive discussions.

Data Availability Statement

Some or all data, models, or code generated or used during the study are available from the corresponding author by request.

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No competing interests reported.

Microvasculature evaluation of monocular anisometropic amblyopia children by Angio-OCT

Status:

Journal Publication

Version 1

Abstract

Background

Methods

Results

Conclusion

Introduction

Materials And Methods

Amblyopia patients

Retinal and choroidal data

Angio-OCT

Data treatment and statistical analysis

Results

Amblyopia patients

Angio-OCT indices

Discussion

Conclusion

Declarations

References

Additional Declarations

Status:

Journal Publication

Version 1