Choroidal vascularity features of fundus tessellation in adults with high myopia

doi:10.21203/rs.3.rs-3309358/v1

Background

To investigate alterations in choroidal vascularity among highly myopic adults with fundus tessellation, utilizing optical coherence tomography.

Methods

Total of 143 highly myopic adults (234 eyes) with fundus tessellation were collected in this retrospective study, which was stratified into different lesion groups based on the novel tessellated classification. Subfoveal choroidal thickness (SFCT), luminal area (LA), stromal area (SA), total choroidal area (TCA), and choroidal vascularity index (CVI) were analyzed utilizing optical coherence tomography (OCT) with enhanced depth imaging (EDI) mode, enabling precise quantification of these parameters.

Results

Comparison analysis demonstrated notable distinctions in spherical equivalent (SE), axial length (AL), and SFCT across the four tessellated grades (p < 0.001). Considerations of the choroidal vascularity parameters, LA, TCA, CVI were significant differences among the four groups (p < 0.001), while no significant variations were observed in SA when comparing Grade 1 versus Grade 2, as well as Grade 2 versus Grade 3 (p > 0.05). Logistic regression analyses illustrated that the higher grade of tessellated exhibited a positive association with AL (OR = 1.701, p = 0.027), while negatively associated with SFCT (OR = 0.416, p = 0.007), LA (OR = 0.438, p = 0.010) and CVI (OR = 0.529, p = 0.004). Multiple regression analyses demonstrated a significant negative association between CVI and both SE and AL after adjusting for age, while positively associated with SFCT (p < 0.05).

Conclusion

Subtle choroidal vascularity changes may have a meaningful contribution to the development and progression of fundus tessellation. CVI and LA were dramatically decreased during the early tessellation development and maintained relatively stable status when developing into severity tessellated grades.

High myopia

Fundus tessellation

Choroidal vascularity

Factors

Binarization

EDI-OCT

Myopia is a pressing global public health issue, with estimates indicating that its prevalence will surge from 33.9% in 2020 to 49.8% in 2050, and the incidence of high myopia is set to climb from 5.2–9.8%, which is also a common issue ascribed to visual damage worldwide, especially in East Asia [1–4]. Notably, high myopia is frequently linked to an elongated axial length which may give rise to several serious and irreversible ocular conditions such as myopic maculopathy, retinal detachment, myopic optic neuropathy, and glaucoma, all of which pose substantial risks to visual function [5, 6]. Given such higher prevalence and severeness of high myopia and myopia-related complications, the earlier-stage characteristics of fundus lesions are warranted.

Fundus tessellation, the initial manifestation of myopic maculopathy, is characterized by the visualization of plainly delineated choroidal vessels around the fovea and arcade vessels according to the META Classification System [7]. Several studies have subsequently reported that early tessellated fundus characterized with younger age, good best-corrected visual acuity, lower degree of myopia, shorter axial length, and reduced occurrence of staphyloma in comparison to other more advanced pathological lesions [8–10]. Additionally, previous research has revealed that the progression of myopic maculopathy could be stable at tessellated fundus stage for a long time, whereas the choroidal thickness (CT) was significantly decreased from the tessellation to peripapillary diffuse choroidal atrophy (PDCA), with an optimal value of 56.5µm in the nasal region from fovea, which could be utilized as a quantitative index to evaluate myopia severity progression [9, 11]. As the choroid is predominantly a vascular structure, alterations in choroidal thickness may stem from modifications in the choroidal vasculature, thereby contributing to the advancement of myopia [12]. It should be acknowledged that CT, as a stand-alone parameter, may not offer a full and accurate reflection of the entire choroidal vasculature and extensively influenced by many physiological and ocular variables, which may lead to possible confounders and comprehensive analysis [13].

Due to improvements in optical coherence tomography (OCT) technology, enhanced depth imaging (EDI)-OCT scans now have the ability to capture high- resolution images with greater penetration depth, conducting a more thorough analysis of relevant parameters and facilitates an efficient evaluation of the potential influence of choroidal structure utilizing innovative quantitative imaging biomarkers [14]. The term choroidal vascularity index (CVI), which is calculated by dividing the luminal area by the total choroidal area, has displayed promising prospects as a non-invasive index for early diagnoses, disease progression monitoring and prognosis evaluation of choroidal microcirculation condition [13]. Prior investigations have implicated that the CVI may serve as a robust marker in myopia and various fundus diseases including diabetic retinopathy [15], central serous chorioretinopathy [16], panuveitis [17], age-related macular degeneration [18], and retinitis pigmentosa [19]. Wu et al. recently also have found CVI was negatively correlated with AL and severity of myopia [20]. However, majority studies of the choroid structure change in tessellated fundus have primarily restricted to alterations in the CT, vascular layer thickness, and choroidal volume [21–23]. Lyu and colleagues proposed a new method for grading fundus tessellation that relied on the ETDRS grid in fundus photographs and found an inverse relationship between CT and fundus tessellation grade [23]. The primary goal of this study was to utilize a novel grading system to quantitatively evaluate choroidal vascularity characteristics and their potential connections with fundus tessellation in adults with high myopia.

Study population

In this retrospective analysis, we recruited a cohort of 143 highly myopic individuals (234 eyes) with tessellated fundus who exhibited both fundus photographs and EDI-OCT examinations at our hospital, including 60 males (95 eyes) and 83 females (139 eyes). The inclusion criteria included adults (age 18 years or older), intraocular pressure (IOP) range from 10 to 21 mmHg, refractive error ≥ − 6.0 D or axial length ≥ 26.0 mm, and the fundus tessellation grade met or exceeded to Grade 1 according to the new classification [23]. The exclusion criteria were other myopic complications (including lacquer cracks, choroidal neovascularization, macular traction syndrome); previous diagnosis of ocular or systemic diseases including but not limited to congenital cataract, glaucoma, hypertension, and diabetes; presence of visual field defects; history of intraocular or refractive surgeries; images that exhibited a poorly defined the choroidal–scleral interface (CSI). The present study followed the ethical principles of the Declaration of Helsinki and was granted approval by the Ethics Committee of Yijishan Hospital prior to commencement. (2019A052).

Classification criteria

To classify the tessellation lesions, we utilized a recently developed grading system that incorporates an ETDRS grid to determine the position of lesions with respect to the fovea [23]. This new proposed classification divides the lesions into five distinct grades including Grade 0, no large choroidal vessels visible; Grade 1, fundus tessellations visible in the posterior pole without involving ETDRS grid; Grade 2, fundus tessellations visible in the outer circle of ETDRS grid without involving the near circle; Grade 3, fundus tessellations visible in the middle circle of ETDRS grid without involving the inner circle; and Grade 4, fundus tessellations visible in the center fovea of ETDRS grid. The photographs included were read by the qualified ophthalmologists (XC and CL) in a concealed analysis to determine the degree of tessellation. A senior ophthalmologist (CW) was involved in the decision-making process when disagreement occurs regarding the grade.

Ocular biometric measurements

A thorough ophthalmologic assessment was conducted on all participants, which involved anterior segment evaluation using slit-lamp biomicroscopy, measurement of IOP with a noncontact tonometer (NT-510, Japan), spherical equivalent refraction measurements with an autorefractometer without the use of cycloplegic agents and calculated by adding the sphere value to half of the cylindrical refraction (KR-8900, Topcon, Tokyo, Japan), and recording axial length utilizing the IOL Master (Carl Zeiss Meditec, Jena, Germany). TRC-50DX was utilized to acquire digital color fundus photographs that were centered on the macula with a 45°dilation (Topcon, Tokyo, Japan). Spectral domain OCT with EDI mode was employed to capture horizontal scans traversing the fovea and raster scans that encompassed all macular abnormalities were acquired (Heidelberg Engineering, Heidelberg, Germany). The subfoveal choroidal thickness (SFCT) was manually measured by utilizing the caliper tool on the OCT device, which involved determining the vertical distance between the Bruch membrane and the CSI as it passed through the center of the fovea.

Choroidal vascularity acquisition

Binarization of the subfoveal choroidal area was carried out using a refined Niblack method on the horizontal line scan with width of 7500µm (3750µm either side of the fovea) from the EDI-OCT images, that process was performed utilizing ImageJ software version 1.53e (accessible at: http://imagej.nih.gov/ij/). The polygon tool was utilized to specify the area of the region of interest (ROI). The vertical expanded of the total choroidal area (TCA) from the retinal pigment epithelium (RPE) as an upper border to the CSI as a lower border was determined manually using the ROI manager. Furthermore, the image was subjected to conversion to 8 bits and adjusted using auto-local threshold (Niblack method), facilitating differentiation between the luminal area (LA) and the stromal area (SA). Upon binarization, the image was transformed back to an RGB format, and the color threshold tool was employed to identify the LA. The ROI manager allowed for the selection and subsequent merging of both areas of interest, resulting in a consolidated ROI. CVI was calculated as the ratio of LA to TCA. Figure 1 represents examples of tessellated fundus photography, as well as corresponding images that were binarized with EDI-OCT both in original form and after the conversion process.

Statistical analysis

SPSS version 26.0 was utilized for conducting the statistical analysis (Chicago, IL, USA). Continuous variables were represented as the mean ± standard deviation, while discrete variables were described as counts (proportions). To evaluate the differences in demographic and ocular parameters between the four groups, the Kruskal-Wallis H test was performed for variables with non-normal distribution, while the one-way analysis of variance (ANOVA) test was used for normally distributed variables. To assess categorical data, the Chi-square test was employed. Multiple logistic regression analysis was conducted to explore the relationship between the grade of fundus tessellation and ocular or systemic parameters, and the linear regression analysis was carried out to determine the influence of other variables on the CVI. Statistical significance was considered as p value less than 0.05.

Demographic and ocular characteristics

A total of 143 highly myopic adults were involved in the study, and the grading of fundus color photographs and OCT images were performed on 234 eyes for the final analysis with ETDRS grid method to further investigate the choroidal vascularity changes. The general characteristics of the 143 adults with tessellation were described as follow. The mean age was 42.63 ± 14.49 years (range of 18 to 75) and 83 (58.04%) of the adults were females. The average value of IOP, SE and AL were 14.32 ± 2.43 mmHg, -11.05 ± 3.82 D (range of -6.00D to -22.75D) and 27.45 ± 1.21 mm (range of 26.0 to 30.79mm), respectively. Considering the choroid parameters, the mean SFCT value was 183.71 ± 65.21µm (range of 70 to 317µm) and the average value of LA, SA, TCA and CVI was 0.85 ± 0.36 mm², 0.72 ± 0.09 mm², 1.57 ± 0.42 mm², and 52.0 ± 8.42%, respectively.

Characteristics of different tessellated grades

Fundus tessellation in the posterior pole occurred in 42 (17.95%), 57 (24.36%), 71 (30.34%) and 64 (27.35%) eyes of Grade 1, 2, 3 and 4 tessellations, respectively. Table 1 presented a comparison of systematic and ophthalmologic parameters across different grades of fundus tessellation. No significant discrepancies were observed in terms of sex and IOP among the four groups. The parameters of age, SE, AL and SFCT were significant differences among separate tessellated grades (p < 0.001). Significant variations were evident in the choroidal vascularity parameters, as LA, TCA and CVI across the four groups (p < 0.001). However, as displayed in the Fig. 2, SA was statistically different among the four groups (p < 0.01) except for the comparison both in Grade 1 and Grade 2, as well as Grade 2 and Grade 3 (p > 0.05).

Multiple logistic regression analyses were performed to identify the factors that were closely linked with fundus tessellation grades, the results were shown in Table 2. The higher degree of tessellated fundus was positively correlated with AL (OR = 1.701, 95%CI: 0.740–1.928, p = 0.027), while negatively related with CVI (OR = 0.529, 95% CI: 0.426–0.658, p = 0.004), LA (OR = 0.438, 95% CI: 0.233–0.823, p = 0.010) and SFCT (OR = 0.416, 95%CI: 0.220–0.784, p = 0.007).

Choroidal vascularity index

Further analyses were carried out using both univariate and multivariate linear regression to determine the variables linked with the CVI, the results were shown in Table 3 and Table 4. The results demonstrated a significant inverse correlated between CVI and age, SE, and AL (p < 0.001), while the age distribution was only significantly different in Grade 4 tessellated group. Multiple regression analyses demonstrated a significant negative association between CVI and both SE and AL with age as a covariate (p < 0.05), while positively associated with SFCT, with significant difference (p < 0.05).

Established the new classification of fundus tessellation with ETDRS grid provide a relatively detailed distinction, which facilitates to effective compare and analysis the choroidal structures in highly myopic adults. As well as, applying deeper penetrating SD-OCT examination accompanied with EDI mode and binarization method of choroidal vascularity measurement, which may provide a higher resolution visualization and quantification of choroidal components.

Earlier investigations have identified a noteworthy link between the fundus tessellation grade and choroidal components both in children and adults [8, 24, 25], whose findings were consistent with our results that tessellated grade was correlated with the AL and SFCT. In the Beijing Eye Study, the higher tessellation grades were correlated with thinner SFCT and longer AL among the elder population [8]. Guo et al. [24] in a school-based study reported that SFCT and CT at a distance of 3-mm to the nasal and temporal sides of the fovea, as well as AL were correlated with the tessellation grade. Additionally, Yoshihara et al. [25] converting the RGB (red, green, blue) pixels of fundus images into three tessellated fundus indices (TFIs) to objectively classified fundus tessellation, also established a relationship between the CT and these TFIs in the area extending from the fovea and to the optic disc.

In several of these studies, the CT was predominantly considered as a surrogate to evaluate structural changes in the choroid. Fang et al. [11] based on the OCT examination was further provided the threshold value of 56.5µm nasal to the fovea for CT that could predict the presence of PDCA from tessellation. However, CT was only representative of the overall choroid structural change, which might not be a reliable indicator of the alteration occurring in the choroidal subcomponents throughout the disease advances, as well as frequently influenced by many physiological and ocular variables, including age, AL, IOP, luminal area, and systolic blood pressure [26]. CVI as a novel EDI-OCT based metric and robust marker that delivers precise insight regarding the choroidal vascular architecture through the use of a binarization method [13]. Previous studies have proved the robust characteristic of CVI both in health population and various diseases concerning the choroid [15–19, 27]. Within the context of this investigation, we utilized CVI to evaluate the choroidal vascularity changes, found that CVI and LA decreased with the severity tessellated grades.

Earlier studies have investigated the choroidal vascularity parameters changes in highly myopic children or adults [27, 28]. In the initial study by Gupta et al. [28] documented a decrease in both choroidal LA and SA, as well as a thinning of CT among individuals with high myopia, while the CVI was increased contrasted with healthy eyes. Recently, Li and colleagues investigated the effects of low to moderate myopia in children demonstrated that LA was decreased with a longer AL and SA tends to decrease with increasing age, whereas CVI was not correlated with AL only associated with age [27]. Partially different from the above findings, our results performed that the severity tessellated grades were associated with reduction in vascular components, as well as the stromal components. The variations in the outcomes could be ascribed to differences in OCT equipment, scan methodologies, age of participants and ethnic diversity. The present study revealed that choroidal LA, SA, TCA and CVI were all decreased with increasing tessellated grades, and the vascular lumen area exhibited a greater reduction than the stromal area. Comparative analysis between each group illustrated that choroidal SA had slight changes both in Grade 1 versus Grade 2 and Grade 2 versus Grade 3, while choroidal LA had a significant decrease with statistical different especially in lower grades. Progression of fundus tessellation from Grade 1 to Grade 2 and further to Grade 3 with a significant decrease of choroidal LA than SA, leading to a substantial decrease of CVI, while the vascularity parameters were only modest changes from Grade 3 to Grade 4. We speculated that the greater decrease of choroidal LA which may be attributed to impaired vasodilatation caused by blood vessels dysfunction, with slight decrease of choroidal SA results from persistent proinflammatory response for culminate fibrosis, these factors together would contribute towards the reduced CVI. And these choroidal vascularity parameters dramatically decreased during the early tessellated development and maintained stable status when progressed into severity level. We suggested that the occurrence of these results may be due to the compensation of peripheral choroid vascularity, which may have been a result of temporary improvements in blood supply brought about by the non-vascular smooth muscle, when fundus lesions intervene in macula. Therefore, further studies about choroidal vascularity changes in tessellated fundus development should be performed.

Liner regression analyses shown that CVI was significantly linked to age, SE, AL and SFCT (p < 0.001), while the age distribution was only significantly different in Grade 4. These findings were partially different from earlier studies. Wu et al. demonstrated an inverse relationship between CVI and AL, with prominent changes manifested in the temporal and inferior macular regions [20]. According to the study conducted by Li et al. [27], CVI had no meaningful relationship with AL only associated with age in myopic children. And Koçak et al. [29] observed choroidal structures in healthy populations found that decreased LA, TCA, and CVI were related with advancing age, and the decrease of SFCT was significantly associated with the reductions of LA and SA. These differences mainly arise from the participant refraction status, age distributions and different group divisions, as the results of Ruiz-Medrano et al. study reported the significant disparities both in adult and pediatric population in terms of choroidal cross-sectional area, vascular area, and CVI showed significant differences between children and adults [30]. Previous research has suggested that scleral hypoxia can result in chorioretinal hypoperfusion in myopic eyes [31], as well as vascular compromise and vascular hypoperfusion may occur as a result of extending and thinning of both retina and choroid [32]. The decrease in CVI, which represented the proportion of luminal area to total choroidal area (comprising both lumina and stroma), suggested that the absence of the choroidal vascular component may have a greater detrimental effect during myopia development than the absence of stroma. Our results indicated that the mechanical strain resulting from axial elongation could cause a significant reduction in CVI, which may have important implications for myopia progression. Hence, a long-term observational study exploring the fluctuations in choroidal vascularity components across different age spans in different tessellated grades is warranted.

Previous investigations have suggested that variances in the scanned area could potentially influence the findings [29, 33]. Such as, Koçak and colleagues in the current study have found that the CVI was greater in the 1500µm subfoveal area when compared to the overall choroidal region [29]. Kakiuchi et al. [33] also concluded that the CVI exhibited a significant increase in the macular region as opposed to the paramacular zone. Sonoda et al. determined that selecting a wider region of the single horizontal line scan, spanning 7500-µm, was more appropriate to accurately determine the binarization of the choroidal area, which was due to circumvent increase variation in the luminal/stromal area ratio when using the smaller sampling areas [34]. These relatively influenced the results due to different areas included. The evaluation of CVI, in this study, necessitated the binarization of a single cross-section scan that was horizontal in orientation and spanned 7500µm across the fovea. In recent articles, three-dimensional CVI was analyzed in myopic eyes using the ration of choroidal vessel volume (CVV) to entire choroidal volume, found that CVI, CVV and CT exhibited a predominantly negative association with AL [35, 36]. Three-dimensional CVV and CVI applying which encompass a wide region and cover a broader range of AL, may prove to be more effective and informative of demonstrating changes in choroidal blood perfusion related to myopia. We will subsequently apply this three-dimensional CVV and CVI index obtained of SS-OCT/SS-OCTA to validate and compensate for the limitations of this study.

This study is subject to several limitations that should be taken into account. First, the CVI value was obtained in the two-dimensional examination mode. Second, the new method for assessing fundus tessellation in this study relied exclusively on color fundus photographs with the ETDRS grid, which presented some subjective bias. But the evaluators were highly skilled ophthalmologists with full experience in this particular field. Third, the CT and choroidal vascular parameters (LA, SA and CVI) measurements were taken with partial manual, which could cause differences results contrasted with other findings. Conversely, this study’s design had the advantage of relatively substantial sample sizes, the performance of new classification and the application of binarization method in CVI measurement.

In conclusion, this study applied the ETDRS grid classification and the binarization method of CVI measurement on investigating the choroidal vascularity changes in tessellated fundus. Both SFCT and vascularity parameters were reduced with tessellated fundus grades in highly myopic adults. These choroidal vascularity parameters dramatically decreased during the early tessellated development and retained stable status when progressed into severity level, which may be helpful for the differential and diagnosis of severe tessellation lesions and can provide a preventive warrant. The tessellated fundus stage, which represents the initial phase of myopic maculopathy, may remain stable for an extended period. So, analyzing the characteristic changes of tessellated fundus at different degrees of high myopia is conducive to further obtaining indicators of early choroidal vascularity changes to control the accelerated development of this stable period, implement prompt intervention and preventive measures.

CVI: Choroidal vascularity index; SFCT: Subfoveal choroidal thickness; LA: Luminal area; SA: Stromal area; TCA: Total choroidal area; OCT: Optical coherence tomography; EDI: Enhanced depth imaging; SE: Spherical equivalent; AL: Axial length; CT: Choroidal thickness; PDCA: Peripapillary diffuse choroidal atrophy; IOP: Intraocular pressure; CSI: Choroidal–scleral interface; ROI: Region of interest; RPE: Retinal pigment epithelium; OR: odds ratio; CI: Confidence interval; TFIs: Tessellated fundus indices

Authors’ contributions

RZ and JX designed the study, analyzed data, interpreted data, revised and supplemented the manuscript; MZ collected data, data analysis and interpretation; XC and CL collected data and measured correspondent fundus parameters; CW designed the study, data interpretation and manuscript revisions. The final version of the manuscript was read, reviewed, and approved by all of the authors involved in this study.

Funding

The funding required to conduct this work was made possible by the Health Commission of Anhui Province (HC-AH 2021-164). No financial funding was received in relation to this research publication.

Availability of data and materials

The data underpinning the results of this study can be made available by the corresponding author upon reasonable request.

Ethics approval and consent to participate

This study was approved by the ethical committee of Wannan Medical College Yijishan Hospital (2019A052). Permission to collect data was included under ethics approval. The informed consent was exempt according to the Institutional Review Board of Wannan Medical College Yijishan Hospital (2019A052) because each patient record was anonymized and deidentified prior to analysis. All methods were carried out in accordance with relevant guidelines and regulations.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

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Table 1 Comparative evaluation of demographic and ocular variables across distinct grades of tessellated fundus

Variables	Grade 1	Grade 2	Grade 3	Grade 4	p
No. of eyes	42	57	71	64	-
Age, years	38.83±12.46	39.86±13.80	41.17±14.51	49.22±14.56	<0.001
Female, n (%)	27 (64.29)	38 (66.67)	39 (54.93)	35 (54.69)	0.419
IOP, mmHg	14.35±2.37	14.32±2.46	14.46±2.58	14.16±2.30	0.995
SE, D	-7.18±0.97	-9.63±2.20	-11.47±2.98	-14.40±3.95	<0.001
AL, mm	26.27±0.18	26.90±0.60	27.47±0.89	28.69±1.17	<0.001
SFCT, μm	265.83±30.28	214.23±46.35	159.32±45.11	129.69±44.53	<0.001
LA, mm²	1.420±0.08	1.036±0.12	0.686±0.15	0.491±0.14	<0.001
SA, mm²	0.773±0.03	0.765±0.03	0.727±0.07	0.629±0.11	<0.001
TCA, mm²	2.193±0.05	1.801±0.09	1.412±0.21	1.120±0.25	<0.001
CVI, %	64.72±2.07	57.35±3.56	48.09±3.18	43.23±2.75	<0.001

SD: Standard deviation; IOP: Intraocular pressure; SE: Spheric equivalent; D: Diopter; AL: Axial length; SFCT: Subfoveal choroidal thickness; LA: Luminal area; SA: Stromal area; TCA: Total choroidal area; CVI: Choroidal vascularity index.

Table 2 Multivariate regression analysis of associated factors for tessellated fundus grades

Variables	Wald	OR	95%CI	p
Age, years	4.110	1.011	0.949-1.077	0.741
SE, D	3.562	1.252	0.692-1.521	0.059
AL, mm	6.979	1.701	0.740-1.928	0.027
SFCT, μm	7.348	0.416	0.220-0.784	0.007
LA, mm²	6.577	0.438	0.233-0.823	0.010
SA, mm²	4.540	1.478	0.620-2.200	0.463
TCA, mm²	2.848	1.201	0.970-1.486	0.092
CVI, %	8.486	0.529	0.426-0.658	0.004

Table 3 Linear regression analysis the potential correlation between systemic and ocular factors and CVI

	Univariate				Multivariate
		Unstandardized β	Standardized β	p	Unstandardized β	Standardized β	p
Age		-0.156	-0.269	<0.001	-0.004	-0.006	0.860
Sex		-0.215	-0.316	0.223	-	-	-
IOP		0.010	0.003	0.965	-	-	-
SE		-0.586	-0.707	<0.001	-0.445	-0.569	<0.001
AL		-0.626	-0.843	<0.001	-0.636	-0.706	<0.001
SFCT		0.815	0.857	<0.001	0.885	0.838	<0.001

β: Regression coefficient

Table 4 Linear regression analysis the potential correlation between systemic and ocular factors and CVI according to different tessellated grades

	Grade 1	Grade 2	Grade 3	Grade 4	Grade 1	Grade 2	Grade 3	Grade 4
Variables	Univariate				Multivariate
	Standardized β				Standardized β
Age	-0.113	-0.009	-0.182	-0.294^*	-	-	-	-0.013
SE	-0.377^*	-0.782^*	-0.775^*	-0.681^*	-0.214	-0.577^*	-0.543^*	-0.441^*
AL	-0.782^*	-0.887^*	-0.845^*	-0.823^*	-0.533^*	-0.781^*	-0.696^*	-0.734^*
SFCT	0.814^*	0.887^*	0.863^*	0.832^*	0.755^*	0.826^*	0.883^*	0.874^*

β: Regression coefficient

*Statistically significant difference.

No competing interests reported.

Choroidal vascularity features of fundus tessellation in adults with high myopia

Status:

Journal Publication

Version 1

Abstract

Background

Methods

Results

Conclusion

Figures

Background

Materials and methods

Study population

Classification criteria

Ocular biometric measurements

Choroidal vascularity acquisition

Statistical analysis

Results

Demographic and ocular characteristics

Characteristics of different tessellated grades

Choroidal vascularity index

Discussion

Conclusion

Abbreviations

Declarations

References

Tables

Additional Declarations

Status:

Journal Publication

Version 1