CHOROIDAL THICKNESS CHANGES AFTER DIABETES TYPE 2 AND BLOOD PRESSURE CONTROL IN A HOSPITALIZED SITUATION

Comparison of the optical coherence tomography-angiography (OCT-A) vascular measurements between molecularly confirmed MODY and age-matched healthy controls

AIMS

Previous structural, vascular density, and perfusion studies have mostly comprised type 1 and type 2 diabetes, even in the absence of retinopathy. The current study aimed to compare macular vessel density (VD) measurements between maturity-onset diabetes of the young (MODY) patients and controls.

METHODS

The macular VD of superficial, deep retina, and choriocapillaris (CC), and central macular thickness (CMT), foveal avascular zone (FAZ), FAZ perimetry, VD of the total retina at 300 µm around the FAZ (FD), and acirculatory index (AI) measurements were taken and analyzed via OCT-A (RTVue XR 100-2 Avanti, AngioVue) and were compared between molecularly confirmed MODY (glucokinase (GCK) variants) patients and healthy controls.

RESULTS

Twenty-five MODY patients and 30 healthy controls were included in the study. The mean plasma hemoglobin A1c level in the MODY group was 6.39 ± 0.38. The mean age was 13.8 ± 2.1 in the MODY group and was 12.6 ± 2.5 years among controls. There was no significant difference in terms of the age, superficial and deep retinal VD, FAZ, FAZ perimetry, CMT, FD, or AI between the groups. Compared to the healthy controls, a slight but significant increase in the CC-VD was detected in the MODY group, but only in the parafoveal and perifoveal regions (p = 0.034, p = 0.009).

CONCLUSION

The significant CC-VD increase in the MODY group might be associated with hyperglycemia and/or relatively poor and vulnerable peripheral vascular CC perfusion compared to the central. Previous thickness and VD results of childhood or adolescent diabetes were distributed in a wider range, suggesting that various factors, including some not yet clearly defined, may affect the choroidal vasculature independently of glycemia or as a contributing factor.

Causal Relationships Between Glycemic Traits and Myopia

Purpose

Little is known about whether sugar intake is a risk factor for myopia, and the influence of glycemic control remains unclear, with inconsistent results reported. This study aimed to clarify this uncertainty by evaluating the link between multiple glycemic traits and myopia.

Methods

We employed a two-sample Mendelian randomization (MR) design using summary statistics from independent genome-wide association studies. A total of six glycemic traits, including adiponectin, body mass index, fasting blood glucose, fasting insulin, hemoglobin A1c (HbA1c), and proinsulin levels, were used as exposures, and myopia was used as the outcome. The inverse-variance-weighted (IVW) method was the main applied analytic tool and was complemented with comprehensive sensitivity analyses.

Results

Out of the six glycemic traits studied, we found that adiponectin was significantly associated with myopia. The genetically predicted level of adiponectin was consistently negatively associated with myopia incidence: IVW (odds ratio [OR] = 0.990; P = 2.66 × 10-3), MR Egger (OR = 0.983; P = 3.47 × 10-3), weighted median method (OR = 0.989; P = 0.01), and weighted mode method (OR = 0.987; P = 0.01). Evidence from all sensitivity analyses further supported these associations. In addition, a higher HbA1c level was associated with a greater risk of myopia: IVW (OR = 1.022; P = 3.06 × 10-5).

Conclusions

Genetic evidence shows that low adiponectin levels and high HbA1c are associated with an increased risk of myopia. Given that physical activity and sugar intake are controllable variables in blood glycemia treatment, these findings provide new insights into potential strategies to delay myopia onset.

Optical coherence tomography findings in three patients with Werner syndrome

Background

Werner syndrome is a rare, autosomal recessive disorder characterised by premature aging. It is a typical hereditary progeroid syndrome that can be difficult to diagnose owing to its rarity and the similarity of some of its symptoms, such as juvenile cataracts, to other common ophthalmologic conditions. Early onset of bilateral cataracts is currently used as the ophthalmological feature for Werner syndrome; however, ophthalmologists often find performing a detailed examination of the medical history and genetic testing for Werner syndrome at the time of an ophthalmologic consultation challenging. If a unique ocular finding was observed on ocular examinations in cases of juvenile bilateral cataracts, we could consider Werner syndrome as a differential diagnosis. 

Case presentation

We documented the cases of three patients with Werner syndrome in whom thinning of the retina in the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) were observed using optical coherence tomography (OCT). Visual field tests revealed the loss of visual field mainly owing to glaucoma.

The thinnig of the choroidal thickness (CT) in three patients was also observed using enhanced depth imaging (EDI)-OCT.

Conclusions

Three patients have thinning of the RNFL, GCC, and choroidal thickness and the loss of visual field. These findings suggest the need for including Werner syndrome in the differential diagnosis when patients presenting with juvenile cataracts of unknown cause also show abnormal retinal and choroidal thinning in the OCT images.

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.

Metabolic Status Modulates Choroidal Thickness - A Possible Early Indicator for Diabetic Eye Complications?

OBJECTIVE

To investigate the impact of metabolic status on choroidal thickness (ChT) in healthy subjects, patients with obesity, and type 2 diabetes.

DESIGN AND METHODS

Fasting blood glucose, insulin, insulin-like growth factor-1 (IGF-1), and ChT measured by optical coherence tomography were assessed in healthy normal-weight (n=17), obese participants (n=20), and obese participants with T2D (n=16).

RESULTS

ChT increased in obese participants and obese participants with T2D as compared to healthy normal-weight participants (P<0.0001). A negative correlation was observed between IGF1 and ChT (r=-0.268, P=0.050) for all cohorts. Furthermore, body mass index (BMI; R²=0.209; P=0.002; beta=0.388) and model assessment-estimated insulin resistance (HOMA-IR; R²=0.074; P=0.015; beta=0.305) were independent variables of ChT, explaining 20.9 and 7.4% of its variance (both p<0.016), whereas age, sex, and IGF-1 were not significant confounders of ChT (p>0.975).

CONCLUSION

ChT is associated with metabolic characteristics, i. e., BMI and HOMA-IR. Due to the key role of choroidal function in retinal physiology, future studies are needed to evaluate whether metabolic traits, ChT, and potential metabolic eye complications are mechanistically linked.

The quantitative measurements of choroidal thickness and volume in diabetic retinopathy using optical coherence tomography and optical coherence tomography angiography; correlation with vision and foveal avascular zone

BACKGROUND

To represent choroidal thickness (CT) and choroidal volume (CV) databases in diabetic retinopathy (DR) patients and healthy control participants using optical coherence tomography (OCT) and enhanced depth imaging OCT (EDI-OCT). No study had evaluated CT at all main stages of diabetic retinopathy in a single study.

METHODS

The study included 176 eyes from 93 patients (39-80 years old; 42% females) who were divided into three groups based on DR severity and normal control group: 39 eyes no DR, 64 eyes NPDR, 33 eyes PDR, and 40 eyes normal control. The CT and CV were measured and statistically analyzed. Intra-observer and inter-observer coefficients of repeatability were calculated.

RESULTS

Subfoveal CT showed persistent thinning from normal group (322.50 ± 69.24) to no-diabetic retinopathy (NDR, 308.33 ± 74.45) to nonproliferative diabetic retinopathy (NPDR, 283.45 ± 56.50) group and then thickening as the patient progressed to proliferative diabetic retinopathy (PDR, 295.17 ± 95.69) (P = 0.087). A significant difference was found between the control group and the NDR, NPDR, and PDR groups in nearly all CT and CV of Early Treatment Diabetic Retinopathy Study macular subfields. Fasting blood sugar (FBS = 189.08 ± 51.3 mg/dl) and diabetes mellitus (DM) duration (13.6 ± 6.5 years) had no noticeable effect on CT. In patients with diabetes, the best-corrected visual acuity (BCVA), diabetic macular edema (DME), and foveal avascular zone (FAZ) were not affected by CT and CV.

CONCLUSIONS

The choroidal thickness decreases from the early stages of diabetic retinopathy up to the NPDR stage, with a subsequent modest rise in CT during the PDR stage. There was no correlation between FBS, diabetes duration, BCVA, DME, and FAZ, and CT.

Choroidal thickness in patients with systemic arterial hypertension: a systematic review and meta-analysis

Background:

The global burden of hypertension is constantly increasing with adverse cardiovascular and ocular sequelae. The association between elevated blood pressure and choroidal thickness (CT), as assessed via optical coherence tomography (OCT), is poorly understood.

Objectives and Design:

Studies including hypertensive adults and normotensive controls undergoing OCT were evaluated for inclusion in this meta-analysis. The primary endpoint was CT difference between hypertensive and normotensive adults.

Data Sources and Methods:

We conducted a systematic review and after searching 1011 results from MEDLINE, ClinicalTrials.gov, medRxiv and Cochrane Library, six studies were deemed eligible and were pooled according to a random-effect model.

Results:

A statistically significant reduction in choroidal thickness was found in hypertensive adults ( n = 454) as compared with normotensive controls ( n = 365) [mean difference: −0.77; 95% confidence intervals: (−1.20, −0.34); p = 0.0004]. The main limitations of this meta-analysis are the relatively small population included and the high statistical heterogeneity ( I2 = 87%) among the various studies. Of note, after excluding one study the heterogeneity was markedly reduced.

Conclusion:

Choroidal thickness is reduced among hypertensive subjects compared with normotensive controls. This finding mandates further examination in the context of long-term clinical outcomes.

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.

Renal function and choroidal thickness using swept-source optical coherence tomography in diabetic patients

AIM

To assess the relationship between choroidal thickness and renal function in diabetic patients.

METHODS

Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-naïve diabetic patients. Demographic data included: age, sex, type and course of diabetes. Ocular data included: severity of diabetic retinopathy; retinal thickness at the central macular region, as well as choroidal thickness at the central and paracentral quadrants, using automatically generated maps by swept-source optical coherence tomography; presence of cystic macular edema; and ocular axial length (AXL). Lab-test parameters included: glycated hemoglobin (HbA1c), albuminuria, albumin/creatinine ratio in urine, and glomerular filtration rate.

RESULTS

A significant negative correlation was mainly observed between several choroidal thicknesses, age (P<0.020) and ocular AXL (P<0.030). On the contrary, a significant positive correlation was found between all choroidal thicknesses, HbA1c (P<0.035) and albuminuria (P<0.040).

CONCLUSION

Choroidal thickness can represent an additional tool to help clinicians predicting the renal status in ocular treatment-naïve diabetic patients.

Pathological Features of Diabetic Retinopathy in Spontaneously Diabetic Torii Fatty Rats

OBJECTIVE

The Spontaneously Diabetic Torii (SDT) fatty rat, established by introducing the fa allele (obesity gene) of the Zucker fatty rat into the SDT rat genome, is a new model of obese type 2 diabetes. We studied the pathologic features of diabetic retinopathy (DR) in this animal.

METHODS

The eyes of SDT fatty, SDT (controls), and Sprague Dawley (SD) rats (normal controls) were enucleated at 8, 16, 24, 32, and 40 weeks of age (n = 5-6 for each rat type at each age). The retinal thicknesses, numbers of retinal folds, and choroidal thicknesses were evaluated. Immunostaining for glial fibrillary acidic protein (GFAP) and vascular endothelial growth factor (VEGF) was performed. Quantitative analyses of the immunopositive regions were performed using a cell-counting algorithm.

RESULTS

The retinas tended to be thicker in the SDT fatty rats and SDT rats than in the SD rats; the choroids tended to be thicker in the SDT fatty rats than in the SD rats. The retinal folds in the SDT fatty rats developed earlier and were more severe than in the SDT rats. Quantitative analyses showed that the GFAP- and VEGF-positive regions in the retinas of the SDT fatty rats were significantly larger than those of the SDT rats.

CONCLUSIONS

SDT fatty rats developed more severe DR earlier than the SDT rats. The SDT fatty rats might be useful as a type 2 diabetes animal model to study DR.

Changes of Subfoveal Choroidal Thickness after Cataract Surgery: A Meta-Analysis

Purpose

To investigate the effect of cataract surgery on subfoveal choroid thickness (SFCT) using enhanced-depth imaging optical coherence tomography (EDI-OCT).

Materials and Methods

Relevant publications were searched systematically through various databases from inception to March 2018. The unit of choroidal thickness measurements is micrometers. Studies comparing SFCT before and after cataract surgery were retrieved. All qualified articles were analyzed using RevMan 5.3.

Results

A total of 13 studies with 802 eyes from 646 patients were identified for inclusion. There was a significant increase of SFCT at 1 week (MD = 6.62, 95% CI: 1.20-12.05, P=0.02, I² = 0%), 1 month (MD = 8.30, 95% CI: 3.20-13.39, P=0.001, I² = 0%), and 3 months (MD = 8.28, 95% CI: 1.84-14.73, P=0.01, I² = 0%) after cataract surgery. In subgroup analysis, SFCT in Asians and patients without nonsteroidal anti-inflammatory drugs (NSAIDs) in postoperative medication was significantly thicker (P < 0.05). No statistically significant increase of SFCT was found in diabetic mellitus (DM) patients for 1 day (P=0.89), 1 week (P=0.59), 1 month (P=0.52), and 3 months (P=0.42) after cataract surgery.

Conclusions

This meta-analysis suggested that SFCT increased since 1 week after the cataract surgery and the increase lasted for at least 3 months. Asians and patients without NSAIDs in postoperative medication were more likely to have a thicker SFCT after cataract surgery, whereas DM patients were less likely to increase in SFCT.

Changes in choroidal thickness and volume are related to urinary albumin excretion in type 2 diabetic patients without retinopathy

Purpose

To evaluate choroidal thickness and volume in patients with type 2 diabetes and microalbuminuria using spectral-domain optical coherence tomography.

Methods

We recruited 37 diabetic patients without diabetic retinopathy (18 normoalbuminuric and 19 microalbuminuric) and 21 healthy controls. Choroidal thickness and volume were mapped using the automated Early Treatment Diabetic Retinopathy Study grid and a topographic map of thickness was generated manually. Choroid was also measured at 10 locations under the fovea, temporally and nasally.

Results

Mean choroidal thickness and volume among patients with diabetes and microalbuminuria was reduced in all locations compared to controls (P<0.05). A sectoral decrease of choroidal thickness and volume was shown between microalbuminuric and normoalbuminuric groups.

Conclusion

Choroidal changes were present in type 2 diabetic patients before clinical development of retinopathy. Microalbuminuria was associated with a decrease in choroidal thickness and volume in diabetic patients without diabetic retinopathy.

Subfoveal choroidal thickness in patients with diabetic retinopathy and diabetic macular oedema

PurposeTo investigate the relationship between subfoveal choroidal thickness, severity of diabetic retinopathy (DR), and the presence of diabetic macular oedema (DMO) using enhanced depth imaging spectral domain optical coherence tomography (EDI-OCT) in patients with type 2 diabetes.MethodsA retrospective study of 145 eyes from untreated, type 2 diabetic patients who attended clinic at the Oxford Eye Hospital between January 2012 and February 2013, and underwent fundus photography and EDI-OCT imaging. Eyes were divided into two groups based on the presence or absence of foveal involving DMO and classified according to retinopathy grade: R1 (mild non-proliferative diabetic retinopathy (NPDR), R2 (moderate-severe NPDR), and R3 (proliferative diabetic retinopathy (PDR). Subfoveal choroidal thickness was measured on the EDI-OCT images and statistically analysed using Student's t-test.ResultsIn mild NPDR (n=87), the mean subfoveal choroidal thickness was 217.7 microns. In moderate-severe NPDR (n=37), the mean subfoveal choroidal thickness was 221.7 microns. In PDR (n=21), the mean subfoveal choroidal thickness was 242.1 microns. There was a statistically significant increase in choroidal thickness in PDR when compared with the mild NPDR group, P=0.027. DMO was associated with a non-statistically significant increase in choroidal thickness (225.4 microns) compared with eyes without DMO (209.3 microns), P=0.13.ConclusionSubfoveal choroidal thickness increased with the severity of diabetic retinopathy but showed no statistically significant association with the presence of DMO. This suggests that the choroidal layer is responsive to retinal vascular changes.

Retinal nerve fiber layer thickness and retinal vessel calibers in children with thalassemia minor

OBJECTIVES

Evaluation of the peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel caliber measurements in children with thalassemia minor.

METHODS

In this cross-sectional and comparative study, 30 thalassemia minor patients and 36 controls were included. Heidelberg spectral domain optical coherence tomography was used for peripapillary retinal nerve fiber layer thickness, subfoveal choroidal thickness, and retinal vessel caliber measurements.

RESULTS

There was no statistically significant difference in retinal nerve fiber layer thickness and subfoveal choroidal thickness between the two groups (p > 0.05). There was no correlation between retinal nerve fiber layer thickness and hemoglobin values. Both the arterioral and venular calibers were higher in thalassemia minor group (p < 0.05).

CONCLUSION

There is increased retinal arterioral and venular calibers in children with thalassemia minor compared with controls.

In Vivo Choroidal Vascular Lesions in Diabetes on Swept-Source Optical Coherence Tomography

Diabetes induces microvascular diseases including diabetic retinopathy and choroidopathy which reciprocally promote the pathogenesis, although optical coherence tomography images of diabetic choroidopathy remains to be documented. Here we evaluated the qualitative characteristics of choroidal vascular lesions in patients with diabetes and their association with diabetic retinopathy on swept-source optical coherence tomography (SS-OCT) images. We retrospectively reviewed 110 consecutive eyes of 110 patients with diabetes and 35 eyes of 35 healthy subjects for whom SS-OCT images (6x6-mm scans centered on the fovea) of sufficient quality were acquired. The curve of chorioretinal sections was flattened using Bruch’s membrane as a reference surface, followed by generation of en-face images. We characterized choroidal vascular lesions and evaluated their association with the logarithm of the minimum angle of resolution visual acuity (logMAR VA), retinal and choroidal thicknesses, and diabetic retinopathy severity. En-face SS-OCT images showed unvisualized vessels in Sattler’s layer in 33 eyes (30.0%). Focal narrowing was seen in choroidal vessels in Haller’s layer in 56 eyes (50.9%). The choroidal vessels ended in the superficial or middle portion of Haller’s layer, referred to as vascular stumps, in 20 eyes (18.2%). Diabetic eyes had these findings more frequently than nondiabetic eyes. The subfoveal choroid was thicker in eyes with focal vascular narrowing and vascular stumps than in eyes without such lesions. Vascular stumps in Haller’s layer were significantly related to diabetic retinopathy severity, logMAR VA, and central retinal and choroidal thicknesses. These novel findings on SS-OCT images would promote the better understanding of complicated pathogenesis in diabetic retinopathy and choroidopathy.

Diabetic choroidopathy: a review of the current literature

Diabetic retinopathy is an increasingly prevalent disease, and a leading contributor to the burden of all-cause blindness worldwide. In addition to retinal changes, choroidal abnormalities are common in patients with diabetes. The first studies concerning this vascular structure were based on histologic, indocyanine angiography and laser Doppler flowmetry techniques, but the development of new optical coherence tomography (OCT) technologies and imaging software for enhanced depth imaging (EDI)-OCT in recent years has made it possible to provide more detailed images of the choroidal anatomy and topography.In diabetic patients, several choroidal changes have been described in the literature throughout the years; the recent focus is choroidal thickness, which is significantly different from that in healthy patients. However, understanding choroidal manifestations of diabetic eye disease remains a real challenge, and this gap is hindering efforts towards better defining choroidal evaluation as a predictive factor for disease evolution and treatment response.This review aims to summarize the recent literature concerning changes in choroidal structure in diabetic patients, the relationship to diabetic retinal disease progression, and finally, the current and potential application of the measurement of variations in choroidal thickness for patient management.

Diabetic Retinal and Choroidal Edema in SDT Rats

We evaluated the features of diabetic retinal and choroidal edema in Spontaneously Diabetic Torii (SDT) rats. We measured the retinal and choroidal thicknesses in normal Sprague-Dawley (SD) rats (n = 9) and SDT rats (n = 8). The eyes were enucleated 40 weeks later after they were diagnosed with diabetes, and 4-micron sections were cut for conventional histopathologic studies. The mean retinal and choroidal thicknesses were significantly thicker in the SDT rats than in the normal SD rats. The choroidal thickness was correlated strongly with the retinal thickness in both rat models. Diabetic retinopathy (DR) and diabetic choroidopathy appeared as edema in the SDT rats. The retinal thickness was correlated strongly with the choroidal thickness in the SDT rats, which is an ideal animal model of both DR and choroidopathy.

Choroidal thickness in diabetic retinopathy in relation to long-term systemic treatments for diabetes mellitus

PURPOSE

To measure central choroidal thickness (CCT) in patients with diabetic retinopathy (DR) and analyze the correlation with clinical backgrounds regarding medications for diabetes mellitus (DM).

METHODS

We retrospectively identified 86 patients with DR (172 eyes) and 43 healthy subjects (57 eyes) who underwent spectral-domain optical coherence tomography. Among the 86 patients with DM who had received no intraocular treatments, 61 were diabetic patients who had continuously received systemic treatments for DM (under treatment group). Twenty-five were patients who had discontinued the treatments or had not received any treatment for DM until this study started (no treatment group).

RESULTS

The results of CCT acquired by 2 masked raters showed a significant correlation coefficient (r = 0.98), indicating high reproducibility in this study. No correlation of CCT was noted between normal (272 ± 71 µm) and DM eyes (264 ± 77 µm), the presence of diabetic macular edema, or CCT and the severity of DR in the patients examined. Interestingly, there was a significant decrease in CCT (175 ± 42 µm) in eyes with mild/moderate nonproliferative DR (NPDR) in the no treatment group (p&lt;0.05), whereas CCT was prominently thicker in eyes with severe NPDR (354 ± 76 µm) and proliferative DR (286 ± 74 µm) than in eyes without DR.

CONCLUSIONS

This study demonstrated that CCT was significantly decreased in the presence of mild/moderate NPDR in the no treatment group, suggesting that a continuously high blood sugar state caused by insufficient treatments for DM may facilitate vascular damage in the choroid in the early stage of DR.

Choroidal thickness in systemic arterial hypertension

PURPOSE

To assess choroidal thickness changes in young adults with systemic arterial hypertension.

METHODS

This prospective study comprised 80 hypertensive patients and 80 healthy control subjects. Choroidal thickness was measured with spectral-domain optical coherence tomography (SD-OCT) (RS-3000, Nidek). Choroidal thickness was obtained at the subfovea, 500 µm, 1000 µm, and 1500 µm nasal to the fovea (N500, N1000, N1500) and 500 µm, 1000 µm, and 1500 µm temporal to the fovea (T500, T1000, T1500). Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were measured with a mercury sphygmomanometer. Only the right eye values were used for statistical comparisons between the groups.

RESULTS

Mean age was 23.8 ± 2.8 years in hypertensive subjects and 23.5 ± 2.1 years in the control group (p = 0.945). All choroidal thickness measurements (mean choroidal thickness, subfoveal choroidal thickness, all nasal and all temporal choroidal thicknesses) were significantly lower in hypertensive subjects (p&lt;0.001 for subfoveal, N500, T500, T1000, T1500; p = 0.001 for N1000; and p = 0.012 for N1500). The correlations between choroidal thickness measurements and blood pressure (SBP, DBP, MAP) were insignificant (p&gt;0.05 for all correlations). Choroidal thickness measurements were also insignificantly correlated with disease duration (p&gt;0.05 for all correlations).

CONCLUSIONS

The results of this study demonstrated that choroidal thickness decreases in patients with systemic arterial hypertension. This may be caused by arteriolar sclerosis and vascular contraction caused by high intravascular pressure in the choroid.