Choroidal thickness changes in non-treated eyes of patients with diabetes: swept-source optical coherence tomography study

Association between choroidal thickness and diabetic macular edema: a meta-analysis

AIMS

To evaluate the association between subfoveal choroidal thickness (SFCT) and diabetic macular edema (DME).

DESIGN

A systematic review and meta-analysis.

METHODS

A retrospective or prospective study comparing SFCT in diabetic retinopathy (DR) patients with and without DME was included. The data were collected from published studies retrieved from PubMed, Web of Science, Embase, Ovid Medline, and Cochrane Library. The final search was conducted on July 2, 2023. Heterogeneity was assessed using I2 statistics, and a random-effects model was used for the meta analysis. This study calculated the weighted mean difference (WMD) and 95% confidence interval (CI) for SFCT.

RESULTS

A total of 26 relevant studies were identified, involving a combined sample size of 3201 eyes (1302 DR-DME eyes and 1899 DR-no DME eyes). The results showed no significance between DR-DME and DR-no DME (WMD = - 3.57 μm; 95% CI -26.54 to 19.41 μm; P = 0.76). Sub-analysis based on nonproliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) subgroups showed that the SFCT of NPDR-DME was significantly thinner than that of NPDR-no DME eyes (WMD = - 19.80 μm; 95% CI - 34.55 to - 5.04 μm; P = 0.009), while there was no significance in SFCT between PDR-DME and PDR-no DME (WMD = - 26.45 μm; 95% CI - 104.00 to 51.11 μm; P = 0.50).

CONCLUSION

The SFCT was thinner in NPDR-DME eyes compared to NPDR-no DME eyes. Thinning SFCT might cause retinal hypoxia, and play an important role in DME occurrence. Additionally, this study highlights the importance of considering DR grades and treatment history when evaluating SFCT between DME and no DME.

Association of SDF-1-3' Gene A Variant with Diabetic Retinopathy in the Hungarian Population

We investigated the association between the SDF-1-3' (c801G > A) variant and the development of diabetic macular edema (DME) or proliferative diabetic retinopathy (PDR) in a Hungarian cohort. SDF-1-3' (c801G > A) was genotyped in 103 patients with diabetic retinopathy and 31 age- and sex-matched non-diabetic controls. Central retinal and choroidal thickness was measured by swept-source optical coherence tomography. The distribution of heterozygous and homozygous SDF-1-3' (c801G > A) genotypes was similar in diabetic and control subjects. The SDF-3'(c801AA) genotype was associated with DME (n = 94 eyes, allele distribution p = 0.006, genotype distribution p = 0.01 OR: 2.48, 95% CL: 1.21-5.08) in both univariable and multivariable modelling, independent of duration and type of diabetes, HbA1C, hypertension and microalbuminuria (p = 0.03). DME occurred earlier in patients carrying the SDF-1 (c801A) allele (Kaplan-Meier analysis, log-rank test p = 0.02). A marginally significant association was found between the presence of the SDF-1 (c801A) allele and the development of PDR (n = 89 eyes, p = 0.06). The SDF-1-3' (c801A) allele also showed a correlation with central retinal (p = 0.006) and choroidal (p = 0.08) thickness. SDF-1-3' (c801G > A) is involved in the development of macular complications in DM independent of critical clinical factors, suggesting that SDF-1 may be a future therapeutic target for high-risk patients, especially those carrying the SDF-1 (c801A) allele.

Analysis of the Choroidal Structure in the Early Stage of Type 2 Diabetic Retinopathy

BACKGROUND AND OBJECTIVE

Our aim was to evaluate the choroidal structure in the early stage of Type 2 diabetic retinopathy (DR).

MATERIALS AND METHODS

The study included patients with nonproliferative diabetic retinopathy (NPDR) without edema (n = 30, NPDR group), patients with diabetes without retinopathy (n = 30, No DR group), and healthy subjects (n = 33, control group). Choroidal thickness (CT), total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascularity index (CVI) were evaluated.

RESULTS

The hypertension (HT) rate was highest in patients with NPDR (63.3%), and lowest in the control group (27.3%). Subfoveal, nasal, temporal CT, TCA, and LA were thinner in patients with diabetes compared to the control group for both patients with and without HT, although not significantly. CTs, TCA, LA, and SA were lower in hypertensive patients than patients without HT in all groups. CVI and LA/SA were significantly lower in NPDR group compared to the controls for both patients with and without HT.

CONCLUSION

In patients with diabetes and before clinical retinopathy develops, the thinning of the CT and CVI begins. A decrease in CVI continues as the retinopathy progresses. HT appears to be a factor that can reduce CT, TCA, LA, and SA. [Ophthalmic Surg Lasers Imaging Retina 2024;55:392-399.].

Choroidal Changes in Patients with Diabetic Retinopathy: A Retrospective Study

This study aimed to investigate the characteristic choroidal changes in patients with diabetic retinopathy and identify factors affecting choroidal thickness (CTh), choroidal vascular index (CVI), and choriocapillaris flow. We retrospectively analyzed 79 eyes of 48 patients with diabetes between August 2021 and February 2022. We collected laboratory data, including HbA1c, serum creatinine, blood urea nitrogen, triglyceride, total cholesterol, high-density lipoprotein, and low-density lipoprotein (LDL) levels. Optical coherence tomography images of the foveal avascular zone, retinal vascular density, choroidal flow, retinal thickness, CTh, and CVI were analyzed. Possible determining factors affecting CTh, CVI, and choriocapillaris flow were analyzed using nonparametric multivariate analysis. LDL (p < 0.001) positively correlated with CTh, whereas CVI (p = 0.007) was negatively correlated with CTh in diabetic patients with diabetes. We also identified a negative correlation between choriocapillaris flow and deep parafoveal retinal vessel density in patients with low-grade diabetic retinopathy (DR), which diminished in those with more advanced DR. Our study provides further information on the changes in choroidal structure and blood flow in patients with diabetes.

Age-Related Macular Degeneration Choroidal Vascular Distribution Characteristics Based on Indocyanine Green Angiography

Purpose

The purpose of this study was to present our findings of the distribution pattern of choroidal arteries and large veins in patients with age-related macular degeneration (AMD) using indocyanine green angiography (ICGA).

Methods

A retrospective analysis was conducted on 980 patients who underwent ICGA at The Second Affiliated Hospital of Xi'an Jiaotong University from 2017 to 2023, including 240 patients with AMD. Secondary image processing was applied to the angiographic videos to obtain posterior distribution maps of choroidal arteries and large veins. Differences between different distribution patterns regarding age, gender, eye laterality, and circulation time were compared. We also conducted a comparison of choroidal vascular distribution characteristics between patients with AMD and patients with diabetic retinopathy (DR) and provided a summary of choroidal vascular distribution patterns in AMD.

Results

The filling patterns of choroidal arteries can be classified into the invisible trunk arteries type, the partially masked trunk arteries type, and the exposed trunk arteries type. The vascular topography of the large choroidal vein can be classified into the watershed type, the non-watershed type, and the unknown type, further divided into six subtypes. The distribution patterns of choroidal arteries and veins were significantly correlated with age (P < 0.001). Left eye, older age, and the exposed trunk arteries type were independent risk factors for non-watershed large choroidal vein (P < 0.05). The non-watershed type was the main characteristic of the venous phase in AMD.

Conclusions

The distribution characteristics of the arterial and venous patterns in AMD suggest atrophy of the small blood vessels in the choroid and insufficient perfusion pressure of the blood flow.

Rates of choroidal loss and ganglion cell-inner plexiform layer thinning in type 2 diabetes mellitus and healthy individuals: a 2-year prospective study

AIMS

To investigate longitudinal choroid and ganglion cell-inner plexiform layer (GCIPL) changes in type 2 diabetes mellitus (T2DM) patients and healthy populations across 2 years.

METHODS

This prospective cohort study included T2DM patients and healthy controls. T2DM patients were divided into mild non-proliferative diabetic retinopathy (NPDR) or non-DR (NDR) groups. Macular choroidal and GCIPL thickness was measured using swept-source optical coherence tomography at baseline and follow-up after 2 years. A linear-mixed effect model compared rates of change in choroidal and GCIPL thicknesses between the three groups.

RESULTS

895 T2DM patients (770 in the NDR group and 125 in the NPDR group) and 847 healthy controls were included. Following 2 years, choroidal thinning occurred at a rate of -7.7±9.2 µm/year, -8.1±8.7 µm/year and -5.2±8.1 µm/year in NDR, NPDR and control groups, respectively (p<0.001). GCIPL loss occurred quickest in NPDR patients (-0.97±0.97 µm/year), followed by NDR (-0.91±0.89 µm/year) and the control group (-0.04±0.55 µm/year) (p<0.001). Following multivariate adjustment, choroidal thinning was -2.04 µm/year (95% CI: -4.05 to -0.03; p=0.047) and -1.95 µm/year (95% CI: -3.14 to -0.75; p=0.001) faster in NPDR and NDR groups than in the control group, respectively, and GCIPL thinning was -1.02 µm/year (95% CI: -1.19 to -0.84; p<0.001) and -0.88 µm/year (95% CI: -0.98 to -0.78; p<0.001) faster in the NPDR and NDR groups than in the control group, respectively.

CONCLUSION

Progressive choroidal and GCIPL thinning occurs in healthy individuals and T2DM patients; however, T2DM undergoes accelerated choroidal and GCIPL loss in NPDR patients.

Choroidal thickness and choroidal vascularity index changes in children with type 1 diabetes mellitus without retinopathy

BACKGROUND

Diabetic retinopathy is one of the most important causes of low vision in the working age group. Retinopathy findings start earlier and have a worse prognosis in type 1 DM. The aim of the this study was to compare the choroidal thickness (CT) and choroidal vascular index (CVI) values of type 1 diabetes mellitus (DM) patients without retinopathy findings in pediatric patients and healthy children.

METHODS

The study included 89 children, including 43 type 1 DM patients and 46 healthy controls. The age, gender, duration of DM, hemoglobin A1c (HbA1c), refractive error, intraocular pressure (IOP) and axial length (AL) of the participants were noted. CT measurements were performed subfoveally, 1000 µm from the fovea in the nasal and temporal quadrants. The total choroidal area (TCA), luminal area (LA) and stromal area (SA) were calculated using the binarization method using the image J program. The CVI was determined by dividing the luminal area by the total choroidal area.

RESULTS

There were no significant differences between the participants in terms of age, gender, spherical equivalent, IOP, and AL. There was no significant difference between the groups in terms of CT. TCA, LA and SA values were significantly higher in the Type 1 DM group (p=0.034, p=0.036, p=0.037, respectively). There was no significant difference between the groups in terms of the CVI.

CONCLUSIONS

The TCA, LA, and SA values were significantly higher in the type 1 DM group. LA/SA and CVI values were lower in the type 1 DM group, although not significantly. There was a negative correlation between the duration of DM and LA/SA as well as CVI. This suggests that vascular reduction starts in the early stages.

The Role of Diabetic Choroidopathy in the Pathogenesis and Progression of Diabetic Retinopathy

Diabetic choroidopathy was first described on histopathological specimens of diabetic eyes. This alteration was characterized by the accumulation of PAS-positive material within the intracapillary stroma. Inflammation and polymorphonuclear neutrophils (PMNs) activation are crucial elements in choriocapillaris impairment. The evidence of diabetic choroidopathy in vivo was confirmed with multimodal imaging, which provides key quantitative and qualitative features to characterize the choroidal involvement. The choroid can be virtually affected in each vascular layer, from Haller's layer to the choriocapillaris. However, the damage on the outer retina and photoreceptor cells is essentially driven by a choriocapillaris deficiency, which can be assessed through optical coherence tomography angiography (OCTA). The identification of characteristic features of diabetic choroidopathy can be significant for understanding the potential pathogenic and prognostic implications in diabetic retinopathy.

Optical coherence tomography evaluation of choroidal structure changes in diabetic retinopathy patients: A systematic review and meta-analysis

Introduction

Diabetic retinopathy (DR) is one of the major causes of blindness among working-aged adults worldwide. This study aimed to evaluate the differences in the subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) using optical coherence tomography (OCT) of patients with diabetic eyes with no retinopathy (NDR) and with diabetic retinopathy (DR).

Methods

We performed a comprehensive literature search of the PubMed, Embase, and Cochrane Library databases up to October 2021. The weighted mean difference (WMD) with the 95% confidence interval (CI) was pooled for continuous outcomes.

Results

Twenty-three cross-sectional studies comprising 2,534 eyes including 1,070 NDR eyes, 1,464 DR eyes were included in the systematic review and meta-analysis. The pooled results showed SFCT was significantly thicker in DR than in NDR patients after adjusting for axial length (WMD = 27.90 μm; 95% CI: 11.51 to 44.28; P = 0.001), and the CVI was significantly lower in DR patients (WMD = −1.59; 95% CI: −2.67 to −0.52; P = 0.004).

Conclusion

We described changes in the SFCT and CVI in DR. Resultantly, the CVI and SFCT may be valuable parameters for monitoring the onset of DR and helpful for a better understanding of the role of the choroid in the pathological process of DR.

Systematic review registration

https://www.crd.york.ac.uk/prospero/#myprospero, CRD42021228738.

Alterations in the Choroidal Sublayers in Relationship to Severity and Progression of Diabetic Retinopathy: A Swept-Source OCT Study

Purpose

To examine the association of baseline choroidal sublayers metrics with the risk of diabetic retinopathy (DR) progression over 2 years, with adjustment for confounding factors that affect choroidal measurements.

Design

Prospective, observational cohort study.

Participants

One hundred three eyes from 62 patients with diabetes mellitus (DM).

Methods

Patients were followed up at 6-month intervals for at least 2 years. Choroidal metrics including choroidal area, choroidal thickness (CT), and choroidal vascularity index were measured for both (1) the choriocapillaris plus Sattler's layer and (2) the Haller's layer within the subfoveal and parafoveal region. Cox proportional models were constructed to estimate the relationship between baseline choroidal metrics and DR progression, adjusted for intereye correlation, established risk factors (i.e., duration of DM, glycated hemoglobin [HbA1c] level, body mass index [BMI], use of insulin, and mean arterial blood pressure [MABP]) and confounding factors of choroidal measurements (i.e., age and axial length). Additional predictive value of choroidal metrics was assessed using the C-statistic.

Main Outcome Measures

Hazard ratios (HRs) calculated by Cox proportional hazards model to demonstrate the associations between baseline choroidal metrics and DR progression.

Results

After adjusting for age, axial length, and intereye correlation, choroidal metrics in Haller's layer at baseline that were associated with a higher risk of DR progression included increases in subfoveal choroidal area (HR, 2.033; 95% confidence interval [CI], 1.179-3.505; P = 0.011), subfoveal plus parafoveal choroidal area (HR, 1.909; 95% CI, 1.096-3.326; P = 0.022), subfoveal CT (HR, 2.032; 95% CI, 1.181-3.498; P = 0.010), and subfoveal plus parafoveal CT (HR, 1.908; 95% CI, 1.097-3.319; P = 0.022). These associations remained statistically significant after additionally adjusting for duration of DM, HbA1c level, BMI, use of insulin, and MABP. Addition of these choroidal metrics significantly improved the discrimination for DR progression when compared with established risk factors alone (e.g., duration of DM and HbA1c; increase in C-statistic ranged from 8.08% to 9.67% [P < 0.05]).

Conclusions

Eyes with a larger choroidal area and CT in Haller's layer at baseline were associated with a higher risk of DR progression over 2 years.

Macular Choroidal Thickness and the Risk of Referable Diabetic Retinopathy in Type 2 Diabetes: A 2-Year Longitudinal Study

Purpose

The purpose of this study was to evaluate the associations between choroidal thickness (CT) and the 2-year incidence of referable diabetic retinopathy (RDR).

Methods

This was a prospective cohort study. Patients with type 2 diabetes in Guangzhou, China, aged 30 to 80 years underwent comprehensive examinations, including standard 7-field fundus photography. Macular CT was measured using a commercial swept-source optical coherence tomography (SS-OCT) device (DRI OCT Triton; Topcon, Tokyo, Japan). The relative risk (RR) with 95% confidence intervals (CIs) was used to quantify the association between CT and new-onset RDR. The prognostic value of CT was assessed using the area under the receiver operating characteristic curve (AUC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

Results

A total of 1345 patients with diabetes were included in the study, and 120 (8.92%) of them had newly developed RDR at the 2-year follow-up. After adjusting for other factors, the increased RDR risk was associated with greater HbA1c (RR = 1.35, 95% CI = 1.17-1.55, P < 0.001), higher systolic blood pressure (SBP; RR = 1.02, 95% CI = 1.01-1.03, P = 0.005), lower triglyceride (TG) level (RR = 0.81, 95% CI = 0.69-0.96, P = 0.015), presence of diabetic retinopathy (DR; RR = 8.16, 95% CI = 4.47-14.89, P < 0.001), and thinner average CT (RR = 0.903, 95% CI = 0.871-0.935, P < 0.001). The addition of average CT improved NRI (0.464 ± 0.096, P < 0.001) and IDI (0.0321 ± 0.0068, P < 0.001) for risk of RDR, and it also improved the AUC from 0.708 (95% CI = 0.659-0.757) to 0.761 (95% CI = 0.719-0.804).

Conclusions

CT thinning measured by SS-OCT is an early imaging biomarker for the development of RDR, suggesting that alterations in CT play an essential role in DR occurrence.

Comparison of choroidal thickness in eyes of diabetic patients with eyes of healthy individuals using optical coherence tomography in a tertiary care hospital

Objectives:

To compare the choroidal thickness in eyes of diabetic patients with eyes of age matched controls using optical coherence tomography in a tertiary care hospital.

Methods:

This Cross sectional study was conducted at the Department of Ophthalmology, Jinnah Postgraduate Medical Centre Karachi, for six months from13^thJanuary 2020 to13^thJuly 2020. The study group comprised of 44 patients with 88 eyes. Patients who fulfill the inclusion criteria that is age ranging from 35 to 80years, either gender, known case of diabetes mellitus and having any type of diabetic retinopathy (HbA1c >7), non-diabetic healthy individuals (HbA1c < 7) and those giving informed consent were included in the study. However, patients having active ocular infections, history of myocardial infarction, stroke, uveitis, any ocular surgery, lasers, intravitreal injections, poor fundus view and not giving consent were excluded. A pre-designed proforma was filled. A baseline ocular examination was performed and choroidal thickness was assessed from retinal pigment epithelium to choroid sclera junction in diabetic and healthy participants of the study group using high resolution Swept source OCT (DRI-OCT-2 Triton; Topcon).

Results:

The average age of the patients was 39.41±15.95 years. According to our study mean central subfoveal choroidal thickness in diabetic eyes was 268.5 ± 66.22 (95% CI 240 – 297) and in non-diabetic healthy participants it was 339.3 ± 71.49 (95% CI 308 – 369) with a p-value of 0.001. However, average choroidal thickness was 261.8 ± 61.93 (95% CI 235 – 288) and 336.0 ± 74.35 (95% CI 304 – 367) in diabetic and non-diabetic healthy population with a p-value of 0.001. Choroidal thickness comparison between gender in diabetic and non-diabetic population also showed similar trend.

Conclusion:

In this study, mean central choroidal thickness as well as average choroidal thickness was significantly reduced in eyes having diabetic retinopathy as compared to participants with non-diabetic healthy eyes. These findings indicate that changes in choroid may be a probable route in the pathogenesis of diabetic retinopathy.

Effect of calcium dobesilate on retrobulbar blood flow and choroidal thickness in patients with non-proliferative diabetic retinopathy

INTRODUCTION

Diabetic retinopathy is one of the most common causes of blindness in work-aging adults and develops in one third of diabetic patients. Calcium dobesilate (CaD) treatment have protective effects on blood retinal barrier (BRB) and anti-oxidant as well as anti-inflammatory properties.

OBJECTIVES

To assess effects of CaD administration on retrobulbar blood flow and choroidal thickness in patients with diabetic retinopathy.

METHODS

In this quasi-experimental study, diabetic patients with diabetic retinopathy (DR) were recruited from Shahid Motahari and Poostchi ophthalmology clinic affiliated to Shiraz University of Medical Sciences. Patients were treated with CaD, 1 gr per day for seven days. Before and after CaD administration, retrobulbar blood flow and subfoveal choroidal thickness were assessed. Retrobulbar blood flow were evaluated by measuring peak systolic velocity (PSV), end diastolic velocity (EDV) and resistive index (RI) of ophthalmic artery (OA), central retinal artery (CRA) and short ciliary artery (SCA).

RESULTS

In this study, 26 DR patients with a mean age of 56.15 ± 8.93 years and mean diabetes mellitus duration of 15.04 ± 7.64 years were enrolled. Subfoveal choroidal thickness was significantly increased from 316.08 ± 61.69 to 327.81 ± 58.03 after CaD treatment (P value < 0.001). PSV of CRA and EDV of all arteries were significantly increased after CaD administration. In addition, RI of all arteries was significantly reduced after CaD treatment (P < 0.001).

CONCLUSION

CaD treatment may improve the ophthalmic blood flow and increase the subfoveal choroidal thickness in DR patients. These results may be suggestive of protective effects of CaD on endothelium function as well as microvascular circulation.

Diabetic macular edema with pachychoroid features

Background

To investigate the clinical features of diabetic macular edema (DME) in eyes with pachychoroid phenotypes using multimodal retinal imaging.

Methods

We retrospectively reviewed 210 eyes from 210 DME patients and analyzed the clinical and imaging parameters, including visual acuity, central macular thickness (CMT), subfoveal choroidal thickness (SFCT) and neural retina layer thickness (NRT). The DME eyes were divided into two groups: group 1 (80 eyes with submacular detachment [SMD]) and group 2 (130 eyes without SMD). The clinical and imaging parameters of 285 eyes from 285 diabetic patients without DME were collected as a control group.

Results

DME eyes with pachychoroid phenotypes were more frequent in group 1 than in group 2 (53 eyes [66.25%] and 53 eyes [40.77%], respectively, P < 0.001). Pachychoroid phenotypes were identified in 108 (37.90%) of the control eyes. CMT and NRT were greater in group 1 than in group 2. In group 1, 37 eyes had SMD combined with focal edema, and 43 eyes had SMD combined with diffuse-type edema. No significant difference in pachychoroid phenotypes was found between the focal and diffuse types (26 [70.27%] and 27 [62.79%], respectively, P = 0.481). In group 2, 70 eyes had focal-type edema, and 60 eyes had diffuse-type edema. No significant difference in the frequency of pachychoroid phenotypes was found (32 [45.71%] and 21 [35.00%], respectively, P = 0.215). Interestingly, among the 70 eyes with focal edema in group 2, 13 (40.6%) and 5 (13.2%) eyes with and without pachychoroid phenotypes showed no definite microaneurysms, respectively.

Conclusion

SMD and focal edema without definite microaneurysms may be clinical manifestations of DME with pachychoroid phenotypes and possibly related to choroidal circulation disturbance in DME.

Choroidal Thickness in Diabetic Patients Without Diabetic Retinopathy: A Meta-analysis

PURPOSE

To evaluate the relationship between diabetic eyes without diabetic retinopathy and healthy eyes in subfoveal choroidal thickness.

DESIGN

Systematic review and meta-analysis.

METHODS

An independent retrospective or prospective clinical study comparing diabetic eyes without diabetic retinopathy and healthy control eyes in the subfoveal choroidal thickness was selected. This study compiled data from publications in PubMed and Web of Science between January 1, 2008, and November 15, 2019. Heterogeneity was statistically quantified by I2 statistics, and meta-analysis was performed using a random-effects model.

RESULTS

Seventeen related studies were identified, including a total of 4,213 eyes, which consisted of 1,197 diabetic eyes without diabetic retinopathy and 3,016 healthy eyes. Meta-analysis clearly showed that the subfoveal choroidal thickness of diabetic eyes without retinopathy was significantly thinner than that of healthy control eyes (weighted mean difference = -14.34 μm; 95% confidence interval: -24.37 to -4.32 μm; P < .005). Similar results were obtained in sub-analysis based on the adjustment of the axial length.

CONCLUSIONS

This study suggests that the subfoveal choroidal thickness was thin in diabetic eyes without retinopathy compared to healthy eyes. Subfoveal choroidal thickness might be an important parameter for the development of diabetic retinopathy in diabetic eyes without retinopathy.

Choroidal Thickness in Diabetes and Diabetic Retinopathy: A Swept Source OCT Study

Purpose

Previous studies on the association between choroidal thickness (CT) and severity of diabetic retinopathy (DR) gave conflicting results. The aim of this study was to evaluate the CT changes in diabetic patients and associated factors in a large sample of Chinese patients with diabetes.

Methods

Type 2 diabetes mellitus patients without history of ocular treatment were recruited from the community health system in Guangzhou, China. The swept source OCT instrument was used to obtain high-definition retina and choroid images. The diabetic retinopathy (DR) status was graded based on the guidelines of the United Kingdom National Diabetic Eye Screening Programme. Univariate and multivariate linear regression analyses was used to explore the association of CT with DR severity, diabetic macular edema (DME), hemoglobin A1c, and vision function.

Results

A total of 1347 patients were included in the final analysis. After adjusting for other factors, the patients with stage R3 DR had significantly thinner CT (β = –29.1 µm, 95% CI –53.8 to –4.4, P = 0.021) in comparison in those with R0. After adjusting for other factors, the CTs were thicker than those in R0 patients with difference of 15.6 µm (95% CI 4.3-26.9, P = 0.007) for outer nasal sector, 15.7 µm (95% CI 3.8-25.5, P = 0.008) for outer inferior, and 12.2 µm (95% CI 0.4-24.0, P = 0.042) for inner inferior sector. The presence of DME and hemoglobin A1c levels did not significantly affect average CT. Higher average CT was significantly associated with better best corrected visual acuity, with a –0.02 LogMAR unit per 100 µm increase in average CT (95% CI –0.03 to –0.01, P < 0.001).

Conclusions

CT increased in the early stage of DR, and further decreased with DR progression. DME was not significantly associated with CT. These findings provide more clues to suggest that choroid alterations play a role in the pathogenesis of DR.

Correlation between Renal Function and Peripapillary Choroidal Thickness in Treatment-Naïve Diabetic Eyes Using Swept-Source Optical Coherence Tomography

Purpose: To investigate the associations of the estimated glomerular filtration rate (eGFR) with peripapillary choroidal thickness (pCT) and retinal nerve fiber layer (pRNFL) thickness in diabetic patients by using swept-source optical coherence tomography (SS-OCT). Methods: Ocular treatment-naïve patients with type 2 diabetes mellitus registered in the community health system in Guangzhou, China, were recruited to participate in this prospective cross-sectional study. The eGFR was determined using the Xiangya formula, and the renal function was categorized into non-chronic kidney disease (non-CKD), mild CKD, and moderate to severe CKD (MS-CKD) according to the guidelines. The pCT and pRNFL thicknesses at 12 o'clock were obtained using an SS-OCT by a circular scan with a diameter of 3.4 mm centering on the optic nerve head, and the data from only one eye in each patient were used. Results: This study included 1,408 diabetic patients, with a mean age of 64.4 ± 7.8 years. The average pCT decreased with renal function deterioration, with 126.0 ± 58.0 μm for non-CKD, 112.0 ± 51.2 μm for mild CKD and 71.0 ± 22.9 μm for MS-CKD, respectively (P < .001). The pCT was found to be significantly thinner in CKD patients in all quadrantes (P < .05 in all regions) with the exception of the inferior quadrant, and the average pCT was positively correlated with eGFR (β = 0.3, 95%CI = 0.0 to 0.6, P = .021) after adjusting for other factors. The pRNFL thickness in the nasal quadrant was significantly reduced in patients with CKD, and pRNFL thickness was positively correlated with eGFR (β = 0.1, 95%CI = 0.0-0.2, P = .009) after adjusting for other factors. Conclusion: Impaired renal function was associated with a reduction of pCT and pRNFL thickness in patients with type 2 diabetes. The measurement of pCT and pRNFL may provide additional information for predicting renal impairment.

Change in peripapillary and macular choroidal thickness change in children with type 1 diabetes mellitus without visual impairment or diabetic retinopathy

PURPOSE

To study the characteristics of choroid thickness (CT) of the optic disc and macula in children with type 1 diabetes mellitus (T1DM) without visual impairment and diabetic retinopathy (DR) and analyse associated factors.

METHODS

A square area of 6 × 6 mm around the centre of the optic disc and macula was scanned. The indices analysed mainly included CT at the macular centre (1 mm), and temporal, superior, nasal or inferior aspect of the inner ring (1-3 mm) and outer ring of (3-6 mm) optic disc and macula. Independent risk factors were analysed using multifactor linear regression.

RESULTS

A total of 44 children with T1DM and 48 healthy subjects were enrolled. The diabetic group showed significant increase in the inferior inner ring of parapapillary CT (100.99 ± 30.42 μm versus 89.41 ± 34.00 μm, p = 0.04) and nasal outer ring of parapapillary CT (157.02 ± 47.35 μm versus 131.15 ± 35.17 μm, p = 0.01) as compared to those values in the healthy controls. Spherical equivalent refraction and family history of hypertension are independent factors of both peripappillary choroid thickness (PPCT) and macular choroid thickness (PMCT). Spherical equivalent refraction (p = 0.01) and serum cholesterol (p = 0.03) were independent factors of the inferior inner ring of parapapillary CT, whereas family history of hypertension was an independent factor of the nasal outer ring of parapapillary CT (p = 0.001).

CONCLUSION

In children with diabetes without DR or visual impairment, the CT increase in nasal outer ring of parapapillary (PPNO) and the inferior inner ring of parapapillary (PPII) may be the characteristic pre-DR alteration at the early stage of DM. For children with higher serum cholesterol and family history of hypertension, the change of the nasal outer ring of parapapillary CT and the inferior inner ring of parapapillary CT may be more advanced.

Thinner Average Choroidal Thickness Is a Risk Factor for the Onset of Diabetic Retinopathy

PURPOSE

To analyze the relationships between choroidal thickness (CT) and diabetes mellitus (DM), diabetic retinopathy (DR), and DR severity in community residents diagnosed with type 2 DM, and to explore whether CT can improve the discriminatory ability of other risk factors to predict the incidence of DR.

METHODS

A total of 1,250 type 2 DM residents and 1,027 healthy controls in Xinjing community of Shanghai participated a cross-sectional survey of eye diseases in 2016. CT was measured using swept-source optical coherence tomography. DR was classified according to the 2002 international clinical classification of DR. A total of 537 subjects with type 2 DM without DR at the 2016 survey were followed up in 2018 to investigate the 2-year incidence of DR. Receiver operating characteristic curve analysis was used to test the accuracy of different indicators in predicting the onset of DR.

RESULTS

The central CT of the control, no DR, mild non-proliferative DR (NPDR), moderate NPDR, severe NPDR, and PDR groups were 223.40, 216.22, 213.57, 211.91, 178.47, and 168.15 μm, respectively (p for trend <0.001), and the average CT (ACT) were 197.83, 186.94, 182.03, 178.00, 156.91, and 136.72 μm respectively (p for trend <0.001). Body mass index (BMI), DM duration, fasting blood glucose, glycosylated hemoglobin (HbA1C), and ACT were risk factors for 2-year DR incidence. For the onset of DR, as predicted by ACT, after tenfold cross validation the average area under the curve was 0.55 (p = 0.048). Addition of ACT did not improve the discriminatory ability of DM duration, BMI, glucose and HbA1C on the incidence of DR (Z = 0.48; p = 0.63).

CONCLUSIONS

As the severity of DR increased, the CT of community type 2 DM patients showed a significant downward trend compared with the healthy controls. Thinner ACT was found to be a risk factor for DR incidence, but it did not improve the discriminatory ability of other risk factors to predict the incidence of DR.

Clinically relevant factors associated with quantitative optical coherence tomography angiography metrics in deep capillary plexus in patients with diabetes

Background

To test clinically relevant factors associated with quantitative artifact-free deep capillary plexus (DCP) metrics in patients with diabetes mellitus (DM).

Methods

563 eligible eyes (221 with no diabetic retinopathy [DR], 135 with mild DR, 130 with moderate DR, and 77 with severe DR) from 334 subjects underwent optical coherence tomography-angiography (OCT-A) with a swept-source OCT (Triton DRI-OCT, Topcon, Inc., Tokyo, Japan). Strict criteria were applied to exclude from analysis those DCP images with artifacts and of poor quality, including projection artifacts, motion artifacts, blurriness, signal loss, B-scan segmentation error, or low-quality score. A customized MATLAB program was then used to quantify DCP morphology from the artifact-free DCP images by calculating three metrics: foveal avascular zone (FAZ), vessel density (VD), and fractal dimension (FD).

Results

166 (29.5%) eyes were excluded after quality control, leaving in the analysis 397 eyes (170 with no DR, 101 with mild DR, 90 with moderate DR, 36 with severe DR) from 250 subjects. In the multiple regression models, larger FAZ area was associated with more severe DR (β = 0.687; p = 0.037), shorter axial length (AL) (β = − 0.171; p = 0.003), thinner subfoveal choroid thickness (β = − 0.122; p = 0.031), and lower body mass index (BMI) (β = − 0.090; p = 0.047). Lower VD was associated with more severe DR (β = − 0.842; p = 0.001), shorter AL (β = 0.107; p = 0.039), and poorer visual acuity (VA) (β = − 0.133; p = 0.021). Lower FD was associated with more severe DR (β = − 0.891; p < 0.001) and with older age (β = − 0.142; p = 0.004).

Conclusions

Quantitative artifact-free DCP metrics are associated with VA, DR severity, AL, subfoveal choroidal thickness, age, and BMI in diabetic patients. The effects of ocular and systemic factors should be considered for meaningful interpretations of DCP changes in DM patients.

Systemic and Ocular Determinants of Choroidal Structures on Optical Coherence Tomography of Eyes with Diabetes and Diabetic Retinopathy

Knowledgeof the choroidal structures in eyes with diabetes and diabetic retinopathy (DR) should provide information on the pathogenesis of DR. A prospective study was performed to determine the systemic and ocular factors that affect the choroidal structures in eyes with diabetes. Two-hundred consecutive diabetic subjects consisted of 160 treatment-naïve patients with different stages of DR and 40 patients with proliferative DR with prior panretinal photocoagulation (PRP). All underwent blood and urine tests and enhanced depth imaging optical coherence tomography (EDI-OCT). The cross-sectional EDI-OCT images of the subfoveal choroid were binarized to measure the total choroidal area (TCA), luminal area, and stromal area. Multivariate regression analyses were performed to determine the systemic and ocular factors that were significantly correlated with the choroidal structures. The subfoveal choroidal thickness, TCA, luminal area, and stromal area were larger at more advanced stage of DR, and smaller in eyes with PRP than those without (P < 0.001). The TCA and stromal area were significantly and positively correlated with the degree of albuminuria (P = 0.034, P = 0.025, respectively). The choroidal lumen and stroma may increase as the stages of DR progress and decrease after PRP. Albuminuria may be associated with the choroidal stromal edema.