Location of Tessellations in Ocular Fundus and Their Associations with Optic Disc Tilt, Optic Disc Area, and Axial Length in Young Healthy Eyes

Prediction of Axial Length From Macular Optical Coherence Tomography Using Deep Learning Model

Purpose

The purpose of this study was to develop a deep learning model for predicting the axial length (AL) of eyes using optical coherence tomography (OCT) images.

Methods

We retrospectively included patients with AL measurements and OCT images taken within 3 months. We utilized a 5-fold cross-validation with the ResNet-152 architecture, incorporating horizontal OCT images, vertical OCT images, and dual-input images. The mean absolute error (MAE), R-squared (R2), and the percentages of eyes within error ranges of ±1.0, ±2.0, and ±3.0 mm were calculated.

Results

A total of 9064 eyes of 5349 patients (total image number of 18,128) were included. The average AL of the eyes was 24.35 ± 2.03 (range = 20.53-37.07). Utilizing horizontal and vertical OCT images as dual inputs, deep learning models predicted AL with MAE and R2 of 0.592 mm and 0.847 mm, respectively, in the internal test set (1824 eyes of 1070 patients). In the external test set (171 eyes of 123 patients), the deep learning models predicted AL with MAE and R2 of 0.556 mm and 0.663 mm, respectively. Regarding error margins of ±1.0, ±2.0, and ±3.0 mm, the dual-input models showed accuracies of 83.50%, 98.14%, and 99.45%, respectively, in the internal test set, and 85.38%, 99.42%, and 100.00%, respectively, in the external test set.

Conclusions

A deep learning-based model accurately predicts AL from OCT images. The dual-input model showed the best performance, demonstrating the potential of macular OCT images in AL prediction.

Translational Relevance

The study provides new insights into the relationship between retinal and choroidal structures and AL elongation using artificial intelligence models.

Longitudinal changes of funduscopic optic disc size, color and cup-to-disc ratio in school children

BACKGROUND

To investigate the relationship between changes in the optic disc size and color, cup-to-disc (C/D) ratio, and axial elongation in schoolchildren.

METHODS

A prospective cohort study was performed in 75 right eyes of elementary school students for six years (from 8.5 to 14.5 years old). In the first and last year, all participants underwent optical axial length measurement and color fundus photography. The optic disc color was calculated by dividing the intensity of red by the sum of the intensity of red, green, and blue. The optic disc area was calculated by modifying the number of pixels according to Bennett's formula. The C/D ratio was calculated by dividing the vertical cup diameter by vertical optic disc diameter. Wilcoxon signed rank test was used to compare these optic disc parameters and axial length in the first and last year.

RESULTS

Mean axial length in the last year (24.82 mm) was significantly longer than that in the first year (23.34 mm). Likewise, the mean optic disc size was significantly smaller in the last year (41,946 pixels) than that in the first year (46,144 pixels). The mean optic disc color in the last year (0.49) was significantly more reddish than that in the first year (0.46), while the mean C/D ratio in last year (0.50) was significantly smaller than that in first year (0.52).

CONCLUSIONS

During the period from 8.5 years to 14.5 years of age, both the optic disc size and C/D ratio became smaller, while the color became more red.

Tessellated fundus occurs earlier than myopia in children aged 3-6 years

BACKGROUND/OBJECTIVES

Tessellated fundus can exist in normal healthy eyes. This study aims to evaluate the occurrence and influencing factors of tessellated fundus in preschool children aged 3-6 years.

SUBJECTS/METHODS

This kindergarten-based cross-sectional study included 1716 children with an age range of 3-6 years. All participants underwent a comprehensive eye examination and a questionnaire. According to the number of quadrants occupied by tessellated fundus around the optic disc in fundus photographs, it was divided into four grades.

RESULTS

600 (35.0%) children had peripapillary tessellation. According to the spherical equivalent (SE), the subjects were divided into three groups: Hyperopia group (SE > + 0.75D, n = 1194)；Pre-myopia group (-0.50D < SE ≤ + 0.75D, n = 455); Myopia group (SE ≤ -0.50D, n = 67). The proportion of peripapillary tessellated fundus was 33.0%, 38.0%, 50.7% respectively. According to the regression analysis, in the non-myopia group (Pre-myopia group and Hyperopia group), the occurrence of peripapillary tessellated fundus was associated with longer axial length (OR, 1.566; 95% CI: 1.229-1.996, p < 0.001) and larger corneal radius of curvature (OR, 1.837; 95% CI: 1.006-3.354, p = 0.048). However, in Pre-myopia group, the corneal radius of curvature was not associated with the occurrence of peripapillary tessellated fundus (p = 0.830). In Hyperopia group, the corneal radius of curvature was associated with the occurrence of peripapillary tessellated fundus (OR, 2.438; 95% CI: 1.160-5.122, p = 0.019).

CONCLUSIONS

The occurrence of peripapillary tessellated fundus is more than 30% in 3-6 year old preschool children. Tessellated fundus can also occur in non-myopic children, and is related to the length of axial length and large radius of corneal curvature.

Convolutional Neural Network-Based Prediction of Axial Length Using Color Fundus Photography

Purpose

To develop convolutional neural network (CNN)-based models for predicting the axial length (AL) using color fundus photography (CFP) and explore associated clinical and structural characteristics.

Methods

This study enrolled 1105 fundus images from 467 participants with ALs ranging from 19.91 to 32.59 mm, obtained at National Taiwan University Hospital between 2020 and 2021. The AL measurements obtained from a scanning laser interferometer served as the gold standard. The accuracy of prediction was compared among CNN-based models with different inputs, including CFP, age, and/or sex. Heatmaps were interpreted by integrated gradients.

Results

Using age, sex, and CFP as input, the mean ± standard deviation absolute error (MAE) for AL prediction by the model was 0.771 ± 0.128 mm, outperforming models that used age and sex alone (1.263 ± 0.115 mm; P < 0.001) and CFP alone (0.831 ± 0.216 mm; P = 0.016) by 39.0% and 7.31%, respectively. The removal of relatively poor-quality CFPs resulted in a slight MAE reduction to 0.759 ± 0.120 mm without statistical significance (P = 0.24). The inclusion of age and CFP improved prediction accuracy by 5.59% (P = 0.043), while adding sex had no significant improvement (P = 0.41). The optic disc and temporal peripapillary area were highlighted as the focused areas on the heatmaps.

Conclusions

Deep learning-based prediction of AL using CFP was fairly accurate and enhanced by age inclusion. The optic disc and temporal peripapillary area may contain crucial structural information for AL prediction in CFP.

Translational Relevance

This study might aid AL assessments and the understanding of the morphologic characteristics of the fundus related to AL.

Quantification of peripapillary nerve fibre elevation and its association with axial length, optic disc tilt, and parapapillary atrophy area in young, healthy eyes

BACKGROUND

Eyes with peripapillary nerve fibre elevation (pNFE) may have a gap between the optic nerve papillary margin on colour fundus photography and Bruch's membrane opening on cross-sectional optical coherence tomography (OCT). This study was conducted to evaluate the quantification of the height of pNFE in young healthy eyes and examine the relationship between pNFE height and axial length.

METHODS

A prospective, observational, cross-sectional study was performed involving 117 right eyes. All participants (mean age 25.8 years) underwent comprehensive ophthalmologic examination involving axial length, fundus photography, and peripapillary and optic disc OCT. pNFE height was defined as the distance between the retinal surface plane and the upper edge of the pNFE in optic disc cross-sectional OCT images. Optic disc tilt was evaluated using a sine curve on retinal nerve fibre layer B-scan images. Parapapillary atrophy (PPA) area in colour fundus images was calculated using ImageJ and corrected using Bennett's formula. We evaluated relationships between pNFE height, axial length, optic disc papillary tilt, and PPA area using Spearman's correlation analysis.

RESULTS

Sixty-five eyes had pNFE, with a mean pNFE height of 84.7 μm. pNFE height was significantly positively correlated with axial length (r = 0.32, p < 0.001), optic disc tilt (r = 0.25, p = 0.008), and PPA area (r = 0.27, p = 0.004).

CONCLUSIONS

pNFE is not rare in young healthy eyes. Eyes with higher pNFE had a longer axial length and larger optic disc tilt and PPA area.

Association of macular outward scleral height with axial length, macular choroidal thickness and morphologic characteristics of the optic disc in Chinese adults

PURPOSE

To identify the relationship of macular outward scleral height (MOSH) with axial length (AL), macular choroidal thickness (ChT), peripapillary atrophy (PPA), and optic disc tilt in Chinese adults.

METHODS

In this cross-sectional study, 1088 right eyes of 1088 participants were enrolled and assigned into high myopia (HM) and non-HM groups. MOSH was measured in the nasal, temporal, superior, and inferior directions using swept-source optical coherence tomography images. The clinical characteristics of MOSH and the association of MOSH with AL, macular ChT, PPA, and tilt ratio were analysed.

RESULTS

The mean age of participants was 37.31 ± 18.93 years (range, 18-86 years), and the mean AL was 25.78 ± 1.79 mm (range, 21.25-33.09 mm). MOSH was the highest in the temporal direction, followed by the superior, nasal, and inferior directions (all p < 0.001). The MOSH of HM eyes was significantly higher than that of non-HM eyes, and it was positively correlated with AL in the nasal, temporal, and superior directions (all p < 0.001). Macular ChT was independently associated with the average MOSH (B = -0.190, p < 0.001). Nasal MOSH was positively associated with the PPA area and the presence of a tilted optic disc (both p < 0.01). Eyes with a higher MOSH in the superior (odds ratio [OR] = 1.008; p < 0.001) and inferior directions (OR = 1.006; p = 0.009) were more likely to have posterior staphyloma.

CONCLUSION

MOSH is an early indicator of scleral deformation, and it is correlated positively with AL and negatively with ChT. A higher nasal MOSH is associated with a larger PPA area and the presence of a tilted optic disc. Higher MOSH values in the superior and inferior directions were risk factors for posterior staphyloma.

CLINICAL TRIAL REGISTRATION

The study was registered at www.

CLINICALTRIALS

gov (Reg. No. NCT03446300).

DeepGraFT: A novel semantic segmentation auxiliary ROI-based deep learning framework for effective fundus tessellation classification

Fundus tessellation (FT) is a prevalent clinical feature associated with myopia and has implications in the development of myopic maculopathy, which causes irreversible visual impairment. Accurate classification of FT in color fundus photo can help predict the disease progression and prognosis. However, the lack of precise detection and classification tools has created an unmet medical need, underscoring the importance of exploring the clinical utility of FT. Thus, to address this gap, we introduce an automatic FT grading system (called DeepGraFT) using classification-and-segmentation co-decision models by deep learning. ConvNeXt, utilizing transfer learning from pretrained ImageNet weights, was employed for the classification algorithm, aligning with a region of interest based on the ETDRS grading system to boost performance. A segmentation model was developed to detect FT exits, complementing the classification for improved grading accuracy. The training set of DeepGraFT was from our in-house cohort (MAGIC), and the validation sets consisted of the rest part of in-house cohort and an independent public cohort (UK Biobank). DeepGraFT demonstrated a high performance in the training stage and achieved an impressive accuracy in validation phase (in-house cohort: 86.85 %; public cohort: 81.50 %). Furthermore, our findings demonstrated that DeepGraFT surpasses machine learning-based classification models in FT classification, achieving a 5.57 % increase in accuracy. Ablation analysis revealed that the introduced modules significantly enhanced classification effectiveness and elevated accuracy from 79.85 % to 86.85 %. Further analysis using the results provided by DeepGraFT unveiled a significant negative association between FT and spherical equivalent (SE) in the UK Biobank cohort. In conclusion, DeepGraFT accentuates potential benefits of the deep learning model in automating the grading of FT and allows for potential utility as a clinical-decision support tool for predicting progression of pathological myopia.

Clinical Features of Fundus Tessellation and Its Relationship with Myopia: A Systematic Review and Meta-analysis

INTRODUCTION

This study aims to assess the existing literature on fundus tessellation (FT), focusing on its prevalence, associated factors, distribution, and progression.

METHODS

Systemic methods were employed to search and gather published literature on FT from databases such as the National Library of Medicine (PubMed), Web of Science (WOS), and Elsevier on July 1, 2023. The quality of the studies was evaluated using the Newcastle-Ottawa Scale (NOS) and the Healthcare Research and Quality (AHRQ) criteria. A meta-analysis was conducted to compare tessellated and normal fundus with respect to age, gender, axial length, and spherical equivalent.

RESULTS

The systematic review included 23 articles, encompassing a total of 3053 eyes in the meta-analysis. The prevalence of FT varied from 43.00 to 94.35%. The severity of FT was significantly associated with older age, male sex, lower body weight index, longer axial length, larger peripapillary atrophy, thinner choroid, thinner sclera, and larger corneal radius of curvature, suggesting a potential progression pattern. Notably, FT was observed predominantly in the macular and peripapillary regions. The meta-analysis revealed that tessellated fundus tended to be associated with older age (mean difference [MD] 4.76, 95% confidence interval [CI] 1.71-7.80, P < 0.01), longer axial length (MD 0.86, 95% CI 0.70-1.02, P < 0.01), and a lower spherical equivalent (MD - 1.16, 95% CI - 1.68 to 0.65, P < 0.01) compared to normal fundus. However, there was no significant difference in the proportion of males between individuals with tessellated and normal fundus (odds ratio [OR] 1.12, 95% CI 0.89-1.42, P = 0.32).

CONCLUSIONS

Overall, this systematic review and meta-analysis shed light on the prevalence, characteristics, and factors associated with FT, offering valuable insights for clinicians and researchers in the field of ophthalmology.

STUDY REGISTRATION

The study protocol was registered on the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42023442486).

Prevalence of Fundus Tessellation and Its Screening Based on Artificial Intelligence in Chinese Children: the Nanjing Eye Study

INTRODUCTION

To investigate the prevalence of fundus tessellation (FT), and the threshold for screening FT using an artificial intelligence (AI) technology in Chinese children.

METHODS

The Nanjing Eye Study was a population-based cohort study conducted in children born between September 2011 and August 2012 in Yuhuatai District of Nanjing. The data presented in this paper were obtained in 2019, when these children were 7 years old and underwent 45° non-mydriatic fundus photography. FT in whole fundus, macular area, and peripapillary area was manually recognized from fundus photographs and classified into three grades. Fundus tessellation density (FTD) in these areas was obtained by calculating the average exposed choroid area per unit area using artificial intelligence (AI) technology based on fundus photographs. The threshold for screening FT using FTD was determined using receiver operating characteristic (ROC) curve analysis.

RESULTS

Among 1062 enrolled children (mean [± standard deviation] spherical equivalent: - 0.28 ± 0.70 D), the prevalence of FT was 42.18% in the whole fundus (grade 1: 36.53%; grade 2: 5.08%; grade 3: 0.56%), 45.57% in macular area (grade 1: 43.5%; grade 2: 1.60%; grade 3: 0.50%), and 49.72% in peripapillary area (grade 1: 44.44%; grade 2: 4.43%; grade 3: 0.85%), respectively. The threshold value of FTD for screening severe FT (grade ≥ 2) was 0.049 (area under curve [AUC] 0.985; sensitivity 98.3%; specificity 92.3%) in the whole fundus, 0.069 (AUC 0.987; sensitivity 95.5%; specificity 96.2%) in the macular area, and 0.094 (AUC 0.980; sensitivity 94.6%; specificity 94.2%) in the peripapillary area, respectively.

CONCLUSION

Fundus tessellation affected approximately 40 in 100 children aged 7 years in China, indicating the importance and necessity of early FT screening. The threshold values of FTD provided by this study had high accuracy for detecting severe FT and might be applied for rapid screening.

Application of Artificial Intelligence to Quantitative Assessment of Fundus Tessellated Density in Young Adults with Different Refractions

INTRODUCTION

The aim of this study was to quantitatively assess fundus tessellated density (FTD) and associated factors by artificial intelligence (AI) in young adults.

METHODS

A total of 1,084 undergraduates (age, 17-23 years old) were enrolled in November 2021. The students were divided into three groups according to axial length (AL): group 1 (AL <24.0 mm, n = 155), group 2 (24 mm ≤ AL <26 mm, n = 578), and group 3 (AL ≥26 mm, n = 269). FTD was calculated by extracting the fundus tessellations as the regions of interest (circle 1, diameter of 3.0 mm; circle 2, diameter of 6.0 mm) and then calculating the average exposed choroid area per unit area of fundus.

RESULTS

Among 1,084 students, 1,002 (92.5%) students' FTDs were extracted. The mean FTD was 0.06 ± 0.06 (range, 0-0.40). In multivariate analysis, FTD was significantly associated with male sex, longer AL, thinner subfoveal choroid thickness (SFCT), increased choriocapillaris vessel density (VD), and decreased deeper choroidal VD (all p < 0.05). In circle 1 (diameter of 3.0 mm) and circle 2 (diameter of 6.0 mm), analysis of variance showed that the FTD of the nasal region (p < 0.05) was significantly larger than that of the superior, inferior, and temporal regions.

CONCLUSION

AI-based imaging processing could improve the accuracy of fundus tessellation diagnosis. FTD was significantly associated with a longer AL, thinner SFCT, increased choriocapillaris VD, and decreased deeper choroidal VD.

Sex judgment using color fundus parameters in elementary school students

PURPOSES

Recently, artificial intelligence has been used to determine sex using fundus photographs alone. We had earlier reported that sex can be distinguished using known factors obtained from color fundus photography (CFP) in adult eyes. However, it is not clear when the sex difference in fundus parameters begins. Therefore, we conducted this study to investigate sex determination based on fundus parameters using binominal logistic regression in elementary school students.

METHODS

This prospective observational cross-sectional study was conducted on 119 right eyes of elementary school students (aged 8 or 9 years, 59 boys and 60 girls). Through CFP, the tessellation fundus index was calculated as R/(R + G + B) using the mean value of red-green-blue intensity in the eight locations around the optic disc. Optic disc ovality ratio, papillomacular angle, retinal artery trajectory, and retinal vessel were quantified based on our earlier reports. Regularized binomial logistic regression was applied to these variables to select the decisive factors. Furthermore, its discriminative performance was evaluated using the leave-one-out cross-validation method. Sex difference in the parameters was assessed using the Mann-Whitney U test.

RESULTS

The optimal model yielded by the Ridge binomial logistic regression suggested that the ovality ratio of girls was significantly smaller, whereas their nasal green and blue intensities were significantly higher, than those of boys. Using this approach, the area under the receiver-operating characteristic curve was 63.2%.

CONCLUSIONS

Although sex can be distinguished using CFP even in elementary school students, the discrimination accuracy was relatively low. Some sex difference in the ocular fundus may begin after the age of 10 years.

Comparing Structure-Function Relationships Based on Drasdo's and Sjöstrand's Retinal Ganglion Cell Displacement Models

Purpose

To compare structure-function relationships based on the Drasdo and Sjöstrand retinal ganglion cell displacement models.

Methods

Single eyes from 305 patients with glaucoma and 55 heathy participants were included in this multicenter, cross-sectional study. The ganglion cell and inner plexiform layer (GCIPL) thickness was measured using spectral domain optical coherence tomography. Visual field measurements were performed using the Humphrey 10-2 test. All A-scan pixels (128 × 512 pixels) were allocated to the closest 10-2 location with both displacement models using degree and millimeter scales. Structure-function relationships were investigated between GCIPL thickness and corresponding visual sensitivity in nonlong (160 eyes) and long (200 eyes) axial length (AL) groups.

Results

In both the nonlong and long AL groups, compared with the no-displacement model, both the Drasdo and the Sjöstrand models showed that the structure-function relationship around the fovea improved (P < 0.05). The magnitude of improvement in the area was either comparable between the model or was larger for the Drasdo model than the Sjöstrand model (P < 0.05). Meanwhile, structure-function relationships outside the innermost retinal region that were based on the Drasdo and Sjöstrand models were comparable to or were even worse than (in the case of the Drasdo model) those obtained using the no-displacement model.

Conclusions

Structure-function relationships evaluated based on both the Drasdo and Sjöstrand models significantly improved around the fovea, particularly when using the Drasdo model. This was not the case in other areas.

Illustration of tessellation in Down syndrome

Background: Tessellated fundus refers to a specific change in the appearance of the internal layers of the eye in which the choroidal large vessels became visible through polygonal hypopigmented areas. Such hypopigmented areas alternate with hyperpigmented zones in a tigroid pattern. Fundus tessellation is often associated with myopia and choroidal thinning.Materials and Methods: We analyzed fundus images from 50 children with Down syndrome and 52 controls.Results: Tessellation was present in 64% of children with Down syndrome, compared with only 13.5% of controls (p < .0001). In most cases, tessellation was located peripapillary, and no difference was observed in tessellation localization between children with Down syndrome and controls (p = .60). Although more prevalent in myopic children with and without Down syndrome, tessellation was present in almost half (48%) of children with Down syndrome with hyperopia versus only 5% of controls with the same refractive status.Conclusions: Mechanical stretching of the choroid could explain the high rate of tessellation in myopes. Other factors must contribute to the higher prevalence of tessellated fundus in children with Down syndrome without myopia. We discuss potentially relevant factors and propose vascular involvement as a contributor to tessellation in our population with Down syndrome. Further studies assessing choroidal vasculature in individuals with Down syndrome are needed to confirm this theory.

Factors in Color Fundus Photographs That Can Be Used by Humans to Determine Sex of Individuals

Purpose

Artificial intelligence (AI) can identify the sex of an individual from color fundus photographs (CFPs). However, the mechanism(s) involved in this identification has not been determined. This study was conducted to determine the information in CFPs that can be used to determine the sex of an individual.

Methods

Prospective observational cross-sectional study of 112 eyes of 112 healthy volunteers. The following characteristics of CFPs were analyzed: the color of peripapillary area expressed by the mean values of red, green, and blue intensities, and the tessellation expressed by the tessellation fundus index (TFI). The optic disc ovality ratio, papillomacular angle, retinal artery trajectory, and retinal vessel angles were also quantified. Their differences between the sexes were assessed by Mann-Whitney U tests. Regularized binomial logistic regression was used to select the decisive factors. In addition, its discriminative performance was evaluated through the leave-one-out cross validation.

Results

The mean age of 76 men and 36 women was 25.8 years. The regularized binomial logistic regression delivered the optimal model for sex selected variables of peripapillary temporal green and blue intensities, temporal TFI, supratemporal TFI, optic disc ovality ratio, artery trajectory, and supratemporal retinal artery angle. With this approach, the discrimination accuracy rate was 77.9%.

Conclusions

Human-assessed characteristics of CFPs are useful in investigating the new theme proposed by AI, the sex of an individual.

Translational Relevance

This is the first report to approach the thinking process of AI by humans and can be a new approach to medical AI research.

Relationship between the Vertical Asymmetry of the Posterior Pole of the Eye and the Visual Field Damage in Glaucomatous Eyes

PURPOSE

This study investigated the relationship between the shape of the posterior pole of the eye and the vertical asymmetry of visual field (VF) damage in glaucomatous eyes.

DESIGN

Cross-sectional study.

PARTICIPANTS

A total of 83 eyes of 43 patients with open-angle glaucoma.

METHODS

The VF was measured using the Humphrey 24-2 or 30-2 Swedish Interactive Thresholding Algorithm (SITA) standard. The vertical asymmetry of VF damage was defined as the difference between the mean total deviation (mTD) values of the superior and inferior hemi-retinas. This difference was calculated for the hemifield, central, middle, and peripheral areas. A vertical cross-sectional image of the macula was obtained, and the magnitudes of superior and inferior retinal tilt (RT) were calculated as the difference between the lower margins of the retinal pigment epithelium (RPE) at the fovea and at a location 2 mm superior or inferior to the RPE. The RT asymmetry was defined as the difference between the inferior and superior RT. Data were analyzed using a multivariate linear mixed model.

MAIN OUTCOME MEASURES

The relationship between mTD asymmetry (hemifield, central, middle, and peripheral) and both RT asymmetry and other factors (intraocular pressure, axial length, corneal radius, age, gender, mean deviation, refraction, and visual acuity) was assessed.

RESULTS

The inferior RT was significantly larger than the superior RT (P < 0.001). Hemifield mTD asymmetry was related to RT asymmetry (P = 0.017). These relationships were significant in the middle (P = 0.029) and peripheral areas (P = 0.023), but not in the central area (P = 0.40). Other factors were not related to mTD asymmetry.

CONCLUSIONS

Vertical asymmetry of the posterior pole was related to the vertical asymmetry of glaucomatous VF damage.

Tessellated fundus appearance and its association with myopic refractive error

The appearance of tessellated fundus in an eye may act as a marker in identifying visual performance, degree of myopia or risk of progression of myopia in a given eye. A systematic literature search using key words was performed using PubMed, Web of Science and Google Scholar and of the 832 studies identified, 10 full-length articles, which met the inclusion criteria, were considered for review. The primary outcome measures were association of tessellated fundus with: (i) visual acuity, (ii) refractive error, (iii) axial length, (iv) choroidal thickness and (v) future progression of myopia when compared to either no myopic maculopathy, or more severe myopic maculopathy. There was no significant difference in the visual acuity noted between eyes with normal fundus and tessellated fundus appearance. Compared to eyes with tessellated fundus, eyes with more severe myopic maculopathy had a four-line decrease in best-corrected visual acuity, more myopia (mean difference 2.75 D, range 0.28-5.78 D) and a longer axial length (mean difference 2 mm, range 2.29 to 1.71 mm). Eyes with tessellated fundus generally exhibited a significant decrease in choroidal thickness compared to eyes with no maculopathy. In mostly older individuals, eyes with tessellated fundus had a better outcome with respect to visual acuity, degree of myopia and axial length compared to other severe myopic maculopathies, but had a worse outcome for choroidal thickness and degree of myopia, compared to eyes with no myopic maculopathy. The features such as reduced choroidal thickness combined with a predilection to infra-temporal and parapapillary regions may indicate regions of stress that are prone to more stretching/atrophic changes. This systematic review demonstrated an association of tessellated fundus with visual acuity, refractive error, axial length and choroidal thickness and hence emphasises the documentation of the presence and location of tessellated fundus appearance that may help in predicting the progression of myopia.

Correlations between local peripapillary choroidal thickness and axial length, optic disc tilt, and papillo-macular position in young healthy eyes

Optical coherence tomography (OCT) has made it possible for clinicians to measure the peripapillary choroidal thickness (ppCT) noninvasively in various ocular diseases. However, the ocular factors associated with the ppCT have not been conclusively determined. The purpose of this study was to determine the relationship between the local ppCT and the axial length, optic disc tilt, and the angle of the papillo-macular position (PMP) in healthy eyes. This was a prospective, observational cross-sectional study of 119 right eyes of 119 healthy Japanese volunteers. The ppCT was manually measured at eight sectors around the optic disc using the B-scan images of the Topcon 3D OCT RNFL 3.4 mm circle scan. The trajectory of the retinal pigment epithelium in the B-scan image was fitted to a sine curve using ImageJ, and the amplitude of the sine curve was used to determine the degree of the optic disc tilt. The PMP angle was determined in the color fundus photographs. The relationships between the ppCT and the axial length, the optic disc tilt, and PMP angle were determined by Spearman and multiple correlation analyses. The mean age was 25.8 ± 3.9 years and the mean axial length was 25.5 ± 1.4 mm. The ppCT was significantly and negatively associated with the axial length (R = -0.43 to -0.24, P<0.01) and positively associated with the PMP angle (R = 0.28 to 0.37, P<0.01) in all eight circumpapillary sectors. The temporal and infratemporal ppCTs were significantly and negatively associated with the optic disc tilt (R = -0.31, -0.20, P<0.05). The results of multiple regression analyses were similar to that of Spearman correlation analysis. In conclusion, the axial length and PMP angle can affect the ppCT in all circumferential sectors, however the tilt of the optic disc is correlated with only some of the sectors. This should be remembered in interpreting the ppCT.