Analysis of Retinal Perfusion in Children, Adolescents, and Young Adults with Type 1 Diabetes Using Optical Coherence Tomography Angiography

Repeatability and reproducibility of quantitative OCT angiography measurements from table-top and portable Flex Spectralis devices

PURPOSE

The recent development of a portable investigational handheld OCT-angiography (OCTA) device has allowed for expansion of imaging into the operating room (OR) in addition to standard in-clinic imaging. The aim of this study was to assess intravisit repeatability and intervisit reproducibility of retinal microvasculature measures and central retinal thickness for in-clinic table-top and portable OR compatible OCTA devices.

METHODS

Repeated 10 × 10 OCTA images were acquired in 20 healthy adult participants on two separate visit days using Spectralis spectral-domain OCTA table-top and investigational armature suspended Flex systems. Intravisit and intervisit intraclass correlation coefficients and average absolute percent difference were calculated for quantitative microvasculature measures and CRT.

RESULTS

120 OCTA images were acquired from 20 subjects (n = 20, mean age 26.7 ± 1.61 years, range 24-30 years) with both devices across two separate imaging days. FAZ and CRT measurements had near complete intravisit and intervisit agreement with ICCs between .97 and 1 for both table-top (FAZ ICC .97, .97; CRT ICC .98-1, .98-.99) and Flex (FAZ ICC .97, .95; CRT ICC .99-1, .98-.99) devices. Vessel density measures demonstrated greater variance with only fair to strong agreement (ICC .32-.75) and average absolute percent differences ranging from 2.96 to 6.63%.

CONCLUSION

FAZ and CRT measures for both devices demonstrated high repeatability and reproducibility; retinal vessel density measures demonstrated less. Differences of less than 7% for retinal microvasculature measurements across time and devices are most likely attributable to expectable variance between repeat scans.

Optical coherence tomography angiography for detection of microvascular changes in early diabetes: A systematic review and meta-analysis

AIMS

To evaluate the effectiveness of optical coherence tomography angiography (OCTA) in detecting early intraocular microvascular changes in diabetic patients.

MATERIALS AND METHODS

A systematic study search was performed on PubMed, Medline, Embase, and the Cochrane Library, ranging from January 2012 to March 2023. Controlled studies compared diabetes mellitus (DM) patients with non-diabetic retinopathy (NDR) or patients with mild non-proliferative diabetic retinopathy (mild NPDR) to healthy people. These studies included parameters of OCTA such as foveal avascular zone (FAZ), vessel density of superficial capillary plexus (VDscp), vessel density of deep capillary plexus (VDdcp), and peripapillary VD. The relevant effect model was used according to the heterogeneity, and the mean difference and 95% confidence intervals were calculated.

RESULTS

A total of 18 studies with 2101 eyes were eventually included in this meta-analysis. Our results demonstrated that early alterations of VDscp, VDdcp, and peripapillary VD in NDR patients had a significant difference compared with healthy people by OCTA (VDscp: WMD = -1.34, 95% CI: -1.99 to -0.68, P < 0.0001. VDdcp: WMD = -2.00, 95% CI: -2.95 to -1.04, P < 0.0001. Peripapillary VD: WMD = -1.07, 95% CI: -1.70 to -0.43, P = 0.0010). However, there was no statistically significant difference in total FAZ between them (WMD = -0.00, 95% CI: -0.02-0.01, P = 0.84). In addition, for patients with mild NPDR, OCTA could illustrate prominent changes in VDscp, VDdcp, and total FAZ compared with healthy people (VDscp: WMD = -6.11, 95% CI: -9.90 to -2.32, P = 0.002. VDdcp: WMD = -4.26, 95% CI: -5.95 to -2.57, P < 0.00001. FAZ: WMD = 0.06, 95% CI: 0.01-0.11, P = 0.03).

CONCLUSIONS

In diabetic patients with or without retinopathy, the parameters of OCTA such as VDscp, VDdcp, and peripapillary vessel density were demonstrated as potential biomarkers in monitoring the early alterations of retinal microangiopathy, while total FAZ may have no significant changes in diabetic patients without retinopathy.

Outer Retinal and Choroidal Changes in Adolescents with Long-Lasting Type 1 Diabetes

This study aimed to assess outer retinal layer (ORL), retinal pigment epithelium (RPE), choroid (Ch) and choriocapillaris (CC) modifications in adolescents with long-lasting (>10 years) type 1 diabetes (T1D) without (noDR) or with diabetic retinopathy (DR). ORL and RPE thickness were measured at optical coherence tomography (OCT) macular scans. Vascular parameters of Ch and CC were quantified after elaboration of macular OCT-angiography (OCTA) images. Insulin dose and auxological and metabolic parameters were correlated with OCT and OCTA findings in patients. ORL thickness was higher in DR eyes than in noDR and healthy controls (HC), and RPE thickness was higher in noDR and DR eyes than in HC, with statistical significance for some sectors in noDR versus HC. No OCTA parameters of CC and Ch differed among groups, and no significant correlation was observed with auxological and metabolic parameters. In conclusion, ORL and RPE were both increased in adolescents with long-lasting T1D. Such changes were not associated with insulin dose and glycemia control, nor to any choroid or choriocapillaris flow change clinically detectable at OCTA, and they could be potential imaging biomarkers of disease progression.

Optical Coherence Tomography and Optical Coherence Tomography Angiography in Pediatric Retinal Diseases

Indirect ophthalmoscopy and handheld retinal imaging are the most common and traditional modalities for the evaluation and documentation of the pediatric fundus, especially for pre-verbal children. Optical coherence tomography (OCT) allows for in vivo visualization that resembles histology, and optical coherence tomography angiography (OCTA) allows for non-invasive depth-resolved imaging of the retinal vasculature. Both OCT and OCTA were extensively used and studied in adults, but not in children. The advent of prototype handheld OCT and OCTA have allowed for detailed imaging in younger infants and even neonates in the neonatal care intensive unit with retinopathy of prematurity (ROP). In this review, we discuss the use of OCTA and OCTA in various pediatric retinal diseases, including ROP, familial exudative vitreoretinopathy (FEVR), Coats disease and other less common diseases. For example, handheld portable OCT was shown to detect subclinical macular edema and incomplete foveal development in ROP, as well as subretinal exudation and fibrosis in Coats disease. Some challenges in the pediatric age group include the lack of a normative database and the difficulty in image registration for longitudinal comparison. We believe that technological improvements in the use of OCT and OCTA will improve our understanding and care of pediatric retina patients in the future.

Diabetic retinopathy in the pediatric population: Pathophysiology, screening, current and future treatments

Diabetic retinopathy (DR) is a sight threatening complication of diabetes mellitus (DM). The incidence of DR in the pediatric population has increased in the last two decades and it is expected to further rise in the future, following the increase in DM prevalence and obesity in youth. As early stages of the retinal disease are asymptomatic, screening programs are of extreme importance to guarantee a prompt diagnosis and avoid progression to more advanced, sight threatening stages. The management of DR comprises a wide range of actions starting from glycemic control, continuing with systemic and local medical treatments, up to para-surgical and surgical approaches to deal with the more aggressive complications. In this review we will describe the pathophysiology of DR trying to understand all the possible targets for currently available or future treatments. We will briefly consider the impact of screening techniques, screening strategies and their social and economic impact. Finally a large part of the review will be dedicated to medical and surgical treatments for DR including both currently available and under development therapies. Most of the available data in the literature on DR are focused on the adult population. The aim of our work is to provide clinicians and researchers with a comprehensive overview of the state of the art regarding DR in the pediatric population, considering the increasing numbers of this diseases in youth and the inevitable consequences that such a chronic disease could have if poorly managed in children.

Continuous Glucose Monitoring-Derived Metrics and Capillary Vessel Density in Subjects with Type 1 Diabetes without Diabetic Retinopathy

Optical coherence tomography angiography (OCTA) is an innovative and reliable technique detecting the early preclinical retinal vascular change in patients with diabetes. We have designed our study to evaluate whether an independent relationship exists between continuous glucose monitoring (CGM)-derived glucose metrics and OCTA parameters in young adult patients with type 1 diabetes without diabetic retinopathy (DR). Inclusion criteria were age ≥ 18 years, diagnosis of type 1 diabetes from ≥ 1 year, stable insulin treatment in the last three months, use of real-time CGM, and CGM wear time ≥ 70%. Each patient underwent dilated slit lamp fundus biomicroscopy to exclude the presence of DR. A skilled operator performed OCTA scans in the morning to avoid possible diurnal variation. CGM-derived glucose metrics from the last 2 weeks were collected through the dedicated software during OCTA. Forty-nine patients with type 1 diabetes (age 29 [18; 39] years, HbA1c 7.7 ± 1.0%) and 34 control subjects participated in the study. Vessel density (VD) of the whole image and parafoveal retina in the superficial (SCP) and deep capillary plexus (DCP) was significantly lower in patients with type 1 diabetes compared to controls. The coefficient of variation of average daily glucose, evaluated by CGM, significantly correlated with foveal and parafoveal VD in SCP and with foveal VD in DCP. High glucose variability might be responsible for the early increase of VD in these areas. Prospective studies may help understand if this pattern precedes DR. The difference we detected between patients with and without diabetes confirms that OCTA is a reliable tool for detecting early retinal abnormalities.

Risk factor analysis and clinical decision tree model construction for diabetic retinopathy in Western China

BACKGROUND

Diabetic retinopathy (DR) is the driving force of blindness in patients with type 2 diabetes mellitus (T2DM). DR has a high prevalence and lacks effective therapeutic strategies, underscoring the need for early prevention and treatment. Yunnan province, located in the southwest plateau of China, has a high pre-valence of DR and an underdeveloped economy.

AIM

To build a clinical prediction model that will enable early prevention and treatment of DR.

METHODS

In this cross-sectional study, 1654 Han population with T2DM were divided into groups without (n = 826) and with DR (n = 828) based on fundus photography. The DR group was further subdivided into non-proliferative DR (n = 403) and proliferative DR (n = 425) groups. A univariate analysis and logistic regression analysis were conducted and a clinical decision tree model was constructed.

RESULTS

Diabetes duration ≥ 10 years, female sex, standing- or supine systolic blood pressure (SBP) ≥ 140 mmHg, and cholesterol ≥ 6.22 mmol/L were risk factors for DR in logistic regression analysis (odds ratio = 2.118, 1.520, 1.417, 1.881, and 1.591, respectively). A greater severity of chronic kidney disease (CKD) or hemoglobin A 1c increased the risk of DR in patients with T2DM. In the decision tree model, diabetes duration was the primary risk factor affecting the occurrence of DR in patients with T2DM, followed by CKD stage, supine SBP, standing SBP, and body mass index (BMI). DR classification outcomes were obtained by evaluating standing SBP or BMI according to the CKD stage for diabetes duration < 10 years and by evaluating CKD stage according to the supine SBP for diabetes duration ≥ 10 years.

CONCLUSION

Based on the simple and intuitive decision tree model constructed in this study, DR classification outcomes were easily obtained by evaluating diabetes duration, CKD stage, supine or standing SBP, and BMI.

Retinal Microvascular and Neuronal Changes Are Also Present, Even If Differently, in Adolescents with Type 1 Diabetes without Clinical Diabetic Retinopathy

The purpose of this study was to evaluate retinal changes in adolescents with childhood-onset, long-lasting type 1 diabetes mellitus (T1D). Patients and healthy controls (HC) underwent optical coherence tomography (OCT) and OCT-angiography (OCTA). Individual macular layers, peripapillary retinal nerve fiber layer (pRNFL), and vascular parameters (vessel area density (VAD), vessel length fraction (VLF) and vessel diameter index (VDI)) of macular superficial vascular (SVP), intermediate (ICP), deep (DCP) and radial peripapillary capillary plexuses (RPCP) were quantified. Thirty-nine patients (5 with (DR group) and 34 without (noDR group) diabetic retinopathy) and 20 HC were enrolled. The pRNFL and ganglion cell layer (GCL) were thicker in noDR compared to HC and DR, reaching statistically significant values versus HC for some sectors. At the macular level, VAD and VLF were reduced in DR versus HC in all plexuses, and versus noDR in SVP (p < 0.005 for all). At the RPCP level, VAD and VDI were increased in noDR versus HC, significantly for VDI (p = 0.0067). Glycemic indices correlated to retinal parameters. In conclusion, in T1D adolescents, retinal capillary and neuronal changes are present after long-lasting disease, even in the absence of clinical DR. These changes modify when clinical retinopathy develops. The precocious identification of specific OCT and OCTA changes may be a hallmark of subsequent overt retinopathy.

Optical Coherence Tomography Angiography in Pediatric Retinal Disorders

Purpose:

The rapid and noninvasive nature of optical coherence tomography angiography (OCTA) makes it a potentially valuable tool for imaging the retina in children. With the optimization of tabletop systems and the development of experimental handheld OCTA devices, there is expanded potential for OCTA in the clinic and the operating room. This article reviews the utility of OCTA in some of the most common pediatric retinal disorders.

Methods:

A thorough computerized PubMed search was performed to review relevant published journal articles to contextualize and identify the role of OCTA in common retinal disorders with vascular involvement affecting children. Pertinent results and findings from original investigations and case reports were summarized.

Results:

The ability to quickly collect both qualitative and quantitative information about retinal microvasculature, in both the clinic and operating room settings, with OCTA, has led to the uncovering of microvascular features and morphologic changes in many pediatric retinal disorders such as Coats Disease, familial exudative vitreoretinopathy, incontinentia pigmenti, sickle cell retinopathy, Stargardt Disease, X-linked juvenile retinoschisis, retinopathy of prematurity, diabetic retinopathy in type 1 diabetes, pediatric retinal tumors, and choroidal neovascularization.

Conclusions:

OCTA is a relevant tool to aid early detection, guide intervention, monitor treatment response, and understand pathogenesis in a number of pediatric retinal disorders.

Parafoveal and peripapillary vessel density in pediatric and juvenile craniopharyngioma patients

We assessed the retinal microvascular alterations detected by optical coherence tomography angiography (OCT-A) in pediatric and juvenile craniopharyngioma (CP) patients with chiasmal compression. We included 15 eyes of 15 pediatric or juvenile CP patients and 18 eyes of 18 healthy subjects. The evaluation of vessel density from the superficial retinal capillary plexus (SRCP), the deep retinal capillary plexus, and the radial peripapillary capillary (RPC) segments was obtained by OCT-A. The association between vessel density measures and functional and structural measurements was also analyzed. There were significant reductions in the nasal sector of the SRCP (p < 0.0001) and all sectors of the RPC segment vessel density (nasal, temporal, and superior; p < 0.0001, inferior; p = 0.0015) in CP patients postoperatively compared to the healthy subjects. The peripapillary retinal nerve fiber layer (r = 0.6602, p = 0.0074) and ganglion cell-inner plexiform layer thicknesses (r = 0.7532, p = 0.0030) were associated with RPC segment vessel density. Visual acuity (r = − 0.5517, p = 0.0330) and temporal visual field sensitivity loss (r = 0.5394, p = 0.0465) showed an association with SRCP vessel density. In pediatric and juvenile patients with CP, parafoveal and peripapillary vascular changes following chiasmal compression were observed. The changes in vascular structures were closely related to structural and functional outcomes.

The relationship between carotid intima-media thickness and microvascular changes in retinal zones and optic disc in patients with type 1 diabetes mellitus

PURPOSE

The aim of this study was to detect early retinal vascular changes with optical coherence tomography angiography (OCTA) in type 1 diabetes mellitus (T1DM) patients without diabetic retinopathy and to evaluate the correlation of the results with carotid intima-media thickness (IMT).

DESIGN

This is a case-control and cross-sectional study.

METHODS

This study included 38 adult patients with T1DM, and 38 age and gender-matched healthy controls. Retinal and optic disc (OD) measurements were taken using OCTA. The carotid artery IMT of each patient was measured using Doppler ultrasonography. Superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density, foveal avascular zone (FAZ), non-flow area (NFA) and foveal density (FD) were analysed in the fovea centred 6 × 6 mm macular area. The superficial capillary plexus and DCP were also scanned centred on the peripapillary region. The correlations between OCTA measurements and carotid IMT, duration of DM and haemoglobin A1c levels in patients with T1DM were evaluated.

RESULTS

The mean values for carotid IMT were significantly higher in diabetic patients than in controls (p < 0.001). The mean values for vessel density SCP, DCP and OD were significantly lower in the diabetic group (p < 0.05). There were correlations between the carotid IMT and duration of T1DM and the evaluated parameters of OCTA.

CONCLUSION

Microvascular changes in the SCP and DCP in patients with T1DM without DR offer important data. OCTA can be used to detect early microvascular changes in patients with T1DM without DR. In addition, a relationship was found between SCP vascular dropout and carotid IMT.

Evaluation of early retinal vascular changes by optical coherence tomography angiography in children with type 1 diabetes mellitus without diabetic retinopathy

PURPOSE

To evaluate macular and peripapillary vascular changes by optical coherence tomography angiography (OCTA) in children with type 1 diabetes mellitus (T1DM) without diabetic retinopathy (DR).

METHODS

This study included 46 patients with T1DM and 46 age-sex matched healthy subjects. All participants were evaluated in terms of macular and optic disk parameters by using AngioVue. Foveal avascular zone (FAZ) area, macular and optic disk vessel density (VD) were analyzed. The correlation of these parameters with metabolic factors such as disease duration, mean hemoglobin A1c (HbA1c), insulin-like growth factor 1 (IGF-1) standard deviation score (SDS), homocysteine (Hcy) level, body mass index (BMI) SDS and daily insulin dose was also investigated in T1DM group.

RESULTS

No significant difference was found in FAZ area and optic disk radial peripapillary capillary (RPC) VD comparing diabetic and control groups. In all macular regions, VD was significantly lower in T1DM versus control group both in superficial capillary plexus (SCP) and deep capillary plexus (DCP). None of the metabolic parameters was correlated with FAZ area and optic disk RPC-VD. Vascular density in SCP was negatively correlated with mean HbA1c and positively correlated with IGF-1 SDS. Homocysteine level was negatively correlated with DCP-VD in all areas.

CONCLUSION

In children with T1DM without clinically apparent DR, VD in SCP and DCP was decreased and OCTA is a valuable imaging technique for detecting early vascular changes. The metabolic parameters such as mean HbA1c, IGF-1 SDS and Hcy affect the macular VD in diabetic children.

TRIAL REGISTRATION NUMBER

2011-KAEK-2, 2021/4, Trial registration date: 02.04.2021.

EARLY RETINAL MICROVASCULAR ABNORMALITIES IN YOUNG ADULTS WITH TYPE 1 DIABETES MELLITUS WITHOUT CLINICALLY EVIDENT DIABETIC RETINOPATHY

PURPOSE

To characterize the early retinal microvascular changes in young adults (age: 22.69 ± 3.50 years) with Type 1 diabetes mellitus without clinically detectable diabetic retinopathy using optical coherence tomography angiography and investigate the associated factors.

METHODS

A total of 36 participants with Type 1 diabetes mellitus (70 eyes) and 34 healthy controls (57 eyes) were retrospectively reviewed. The analyzed optical coherence tomography angiography indices included capillary vessel density, foveal avascular zone area/perimeter/acircularity index, and foveal vascular density, acquired in the 6 × 6-mm2 area centered on the fovea. The generalized estimation equations model was applied to compare the mean values and to study the associated factors.

RESULTS

In subjects with diabetes, statistically significant decreases were observed in parafoveal vessel density in both superficial and deep capillary plexuses, foveal avascular zone area/perimeter, and foveal vascular density when compared with controls (all P < 0.05). Higher glycated hemoglobin level was independently associated with the decrease of parafoveal vessel density as well as the increase of foveal avascular zone area/perimeter (all P < 0.05). Prepubescent onset of diabetes mellitus was also independently associated with the decrease of superficial parafoveal vessel density, foveal avascular zone area/perimeter, and foveal vascular density (P = 0.015, 0.011, 0.015, and 0.001, respectively).

CONCLUSION

In young adults with Type 1 diabetes mellitus lacking clinical signs of diabetic retinopathy, optical coherence tomography angiography revealed alterations in retinal microvasculature that were associated with glycated hemoglobin level and onset of diabetes mellitus related to puberty.

Diabetic Retinopathy in Children with Type 1 Diabetes-Occurrence and Screening Using Optical Coherence Tomography

PURPOSE

To describe the occurrence of diabetic retinopathy, the principles for pediatric care of patients with diabetes, and the utility of optical coherence tomography. Pediatric patients with type 1 diabetes should be screened for diabetic retinopathy upon the lapse of 5 years following the diagnosis. The patients in the time of puberty, who should be screened promptly after the diabetes diagnosis, and patients with type 2 diabetes are the exceptions. Special attention must be paid not only to retinopathy, but also to other possible concomitant conditions, such as cataract, refractive errors, or neuropathy. New techniques, such as optical coherence tomography angiography (OCTA), may contribute greatly to the early detection of retinopathy, facilitating the decision to modify the treatment. The application of modern insulin pumps with continuous glucose monitoring systems has greatly diminished the incidence rate of early symptoms of diabetic retinopathy in the pediatric population.

RETINAL TISSUE PERFUSION REDUCTION BEST DISCRIMINATES EARLY STAGE DIABETIC RETINOPATHY IN PATIENTS WITH TYPE 2 DIABETES MELLITUS

PURPOSE

To determine retinal microcirculation measured as retinal tissue perfusion (RTP) in patients with type 2 diabetes mellitus and mild nonproliferative diabetic retinopathy, and to compare its discrimination ability to that of retinal microvasculature and microstructure.

METHODS

Thirty eyes of 18 patients with mild nonproliferative diabetic retinopathy and 20 eyes of 20 age-matched and gender-matched normal controls were imaged. Retinal blood flow velocity and flow rate were measured using a retinal function imager. Retinal vessel density (Dbox) and intraretinal layer thicknesses were measured using optical coherence tomography angiography. Retinal tissue perfusion was measured as retinal blood flow divided by the volume of the inner retina.

RESULTS

Compared with normal control, RTP, vessel density, and the thickness of the retinal nerve fiber layer in patients with mild nonproliferative diabetic retinopathy showed significant reduction (P < 0.05). Retinal tissue perfusion had the best discrimination power (area under the curve = 0.97), with a sensitivity of 93.3% and specificity of 85.0%. In the eyes with mild nonproliferative diabetic retinopathy, RTP correlated with arteriolar blood flow velocity (r = 0.403, P = 0.027) but was unrelated to vessel density in any layer (r = -0.010 to 0.261, P > 0.05).

CONCLUSION

Because of its highest discrimination power, RTP may become a promising biomarker for detecting early-stage diabetic retinopathy.

Influence of puberty on retinal microcirculation in children with type 1 diabetes without retinopathy using optical coherence tomography angiography

BACKGROUND

This study aimed to assess the influence of pubertal status on the results of optical coherence tomography angiography (OCTA) in children with type 1 diabetes (T1D).

METHODS

We enrolled 167 consecutive children with T1D. Retinal superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density data underwent analysis. We divided the study population into three subgroups depending on the pubertal status.

RESULTS

Analysis of the prepubertal and pubertal subgroups revealed statistically significant differences in foveal thickness (FT) (p < 0.05) and foveal SCP (p < 0.02). Analyzing subgroups of the prepubertal and postpubertal children, we observed statistically significant differences in FT (p < 0.03), whole SCP (p < 0.02), and foveal SCP (p < 0.02). Comparison of the pubertal and postpubertal subjects revealed differences in parafoveal DCP (p < 0.003). In the groups matched depending on diabetes duration, we observed differences between prepubertal, pubertal, and postpubertal children in FT, PFT, and parafoveal SCP and DCP.

CONCLUSION

Our data suggest that in a cohort of pubertal children with a short duration of diabetes, alterations in retinal vessel density occur early and progress during puberty.

Remodeling of Retinal Microcirculation Is Associated With Subclinical Arterial Injury in Hypertensive Children

[Figure: see text].

Quantitative Analysis of the Macular and Peripapillary Capillary Network with Optical Coherence Tomography Angiography in Chinese Adolescents: The Tuyou County Pediatric Eye (TYPE) Study

Aim

To use OCTA to collect normative data describing the vascular perfusion of the macula and optic disc in adolescents.

Methods

This cross-sectional, school-based study was conducted from Oct 15, 2019, to Nov 30, 2019, in Tuyou County, Baotou, China. All eligible participants underwent a comprehensive questionnaire and ocular examination. The vascular perfusion of the macula and optic disc was determined using a spectral-domain OCTA device.

Results

A total of 570 anatomically normal eyes without a history of pathologic disease from 570 adolescents (mean ± SD age, 15.1 ± 1.9 years; 298 girls [52.3%]) were enrolled. In the macula, the mean ± SD perifoveal perfusion density (PD) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) was 44.2% ± 4.37% and 50.74% ± 3.98%, respectively. The mean ± SD foveal avascular zone (FAZ) was 0.32 mm² ± 0.11 mm². The mean ± SD peripapillary vessel density (PVD) was 54.98% ± 3.53%. The inferior hemiretinal SCP-PD, DCP-PD, FAZ, and PVD was larger in girls than boys (P = 0.006, P = 0.001, P < 0.001, and P = 0.006, respectively) Multiple regression analysis confirmed that sex independently affected the DCP-PD, FAZ, and PVD (P < 0.001, P < 0.001, and P = 0.029, respectively) and that axial length (AL) independently affected the FAZ area and PVD (P = 0.004 and P < 0.001, respectively).

Conclusion

Quantitative studies of the perifoveal vasculature in adolescents should consider the patient’s sex and AL. Our findings may provide useful information for the understanding and the management of retinal perfusion in Chinese adolescents.

Optical Coherence Tomography Angiography in Type 1 Diabetes Mellitus. Report 1: Diabetic Retinopathy

Purpose

The purpose of this study was to evaluate specifically in type 1 diabetes mellitus (DM) individuals the relationship between perifoveal superficial capillary plexus (SCP) parameters assessed by optical coherence tomography angiography (OCTA) and diabetic retinopathy (DR) grade.

Methods

Cross-sectional analysis of a large scale prospective OCTA trial cohort (ClinicalTrials.gov NCT03422965). A total of 1186 eyes (593 individuals), 956 type 1 DM eyes (478 patients), and 230 control eyes (115 healthy volunteers) were included in this study. DR stage was graded according to the International Classification. OCTA imaging was performed with a commercially available device (Cirrus HD-OCT). Vessel density (VD), perfusion density (PD), and foveal avascular zone (FAZ) area, perimeter and circularity measurements were quantified in the SCP and receiver operating characteristic (ROC) curves were constructed for each OCTA parameter.

Results

VD and PD (in both 3 × 3 and 6 × 6 mm captures) were inversely associated with DR stage (P < 0.001 in all cases) in a multiple regression analysis after controlling by age, gender, signal strength index, axial length, and DM duration. Greater FAZ area and perimeter and conversely lower circularity measurements were observed as DR severity increased in both scanning protocols (P < 0.05 in all cases).

Conclusions

In type 1 DM individuals, OCTA provides an objective, continuous, and reliable method for accurate quantification of VD, PD, and FAZ parameters in the SCP, which ultimately correlate with DR stages.

Translational Relevance

Objective OCTA measurements of the retinal microvasculature could substitute the clinical DR classification in patients with type 1 DM, identify patients at risk of DR progression, and inform treatment decisions to modify the evolution of the disease.

Evaluation of microvascular changes in retinal zones and optic disc in pediatric patients with type 1 diabetes mellitus

PURPOSE

The objective of this study was to evaluate the vascular parameters of the retinal zones and the optic disc (OD) with the use of optical coherence tomography angiography (OCTA) in pediatric patients with type 1 diabetes mellitus (T1DM).

METHODS

This study enrolled 60 patients with T1DM without clinically detectable diabetic retinopathy (DR), along with 59 age-, gender-, and pubertal stage-matched controls. The ages of the participants in both groups were < 18 years. Retinal and OD measurements were carried out with OCTA. Foveal avascular zone (FAZ) area, non-flow area (NFA), FAZ perimeter (PERIM), acircularity index of FAZ (AI, the rate of the perimeter of FAZ and the perimeter of a circle with equal area), foveal density (FD), superficial (SCP), and the deep capillary plexus (DCP) were analyzed in the macular region. SCP and DCP were also scanned centered on the OD. Correlations between the OCTA parameters with duration of DM, glycated hemoglobin (HbA1c) levels, and microalbuminuria were evaluated among patients with T1DM.

RESULTS

The mean values for NFA were significantly higher and mean FD were significantly lower in the diabetic group compared with the controls (p = 0.02 and p = 0.01, respectively). The mean values for SCP and DCP were significantly lower in diabetic group (p < 0.05). The mean values for capillary density in the OD were also significantly lower in diabetic group (p < 0.05). There were correlations between the duration of T1DM, HbA1c levels and microalbuminuria, and the investigated parameters of OCTA.

CONCLUSIONS

The presence of microvascular changes in both retinal zones and the OD in children with T1DM without retinopathy is an important data. OCTA can be used for the early detection of DR in children.

Influence of Metabolic Parameters and Treatment Method on OCT Angiography Results in Children with Type 1 Diabetes

AIM

To evaluate the influence of metabolic parameters and the treatment method in children with type 1 diabetes (T1D) on the optical coherence tomography angiography (OCTA) results as early markers of diabetic retinopathy (DR). Material and Methods. This prospective study enrolled 175 consecutive children with T1D. OCTA was performed using AngioVue (Avanti, Optovue). Whole superficial capillary vessel density (wsVD), fovea superficial vessel density (fsVD), parafovea superficial vessel density (psVD), whole deep vessel density (wdVD), fovea deep vessel density (fdVD), parafovea deep vessel density (pdVD), foveal thickness (FT), parafoveal thickness (PFT), and foveal avascular zone (FAZ) in superficial plexus were evaluated and analyzed in relation to individual characteristics, i.e., sex, weight, height, body mass index (BMI), and metabolic factors: current and mean value of glycated hemoglobin A1c (HbA1c). Furthermore, the analysis concerned the diabetes duration, age at the T1D onset, and type of treatment-multiple daily insulin injections (MDI) or continuous subcutaneous insulin infusion (CSII).

RESULTS

In the study group, we did not identify any patient with DR in fundus ophthalmoscopy. Age at the onset of diabetes correlated negatively with FAZ (r = -0.17, p < 0.05). The higher level of HbA1c corresponded to a decrease of wsVD (r = -0.13, p < 0.05). We found significantly lower fsVD (32.25 ± .1 vs. 33.98 ± .1, p < 0.01), wdVD (57.87 ± .1 vs. 58.64 ± .9, p < 0.01), and pdVD (60.60 ± .2 vs. 61.49 ± .1, p < 0.01) and larger FAZ area (0.25 ± .1 vs. 0.23 ± .1, p < 0.05) in the CSII vs. MDI group.

CONCLUSION

The metabolic parameters, age of the onset of diabetes, and treatment method affected the OCTA results in children with T1D. Further studies and observation of these young patients are needed to determine if these findings are important for early detection of DR or predictive of future DR severity.

Associations between Macular OCT Angiography and Nonproliferative Diabetic Retinopathy in Young Patients with Type 1 Diabetes Mellitus

METHODS

OCTA of both eyes was performed in a cross-sectional study of 14 to 30-year-old individuals with at least 10-year duration of T1D and controls recruited from the Norwegian Atherosclerosis and Childhood Diabetes (ACD) study. Vessel density (VD) and foveal avascular zone (FAZ) area in the superficial and deep capillary plexus (SCP and DCP), total retinal volume (TRV), and central macular thickness (CMT) were calculated using automated software. Univariate and multivariate ordered logistic regression (OLR) models were used accordingly.

RESULTS

We included 168 control eyes and 315 T1D eyes. Lower VD in DCP (OR 0.65, 95% CI 0.51-0.83), longer diabetes duration (OR 1.51, 95% CI 1.22-1.87), and higher waist circumference (OR 1.08, 95% CI 1.02-1.14) were significantly associated with progression of NPDR. VD in SCP and DCP were significantly lower in T1D patients without diabetic retinopathy than in controls.

CONCLUSIONS

Sparser VD in DCP is significantly associated with severity of NPDR, supporting that OCTA might detect the earliest signs of NPDR before it is visible by ophthalmoscopy.