NONEXUDATIVE INTRARETINAL FLUID IN INTERMEDIATE AGE-RELATED MACULAR DEGENERATION

BACKGROUND

To describe the occurrence of nonexudative intraretinal fluid (IRF) in intermediate age-related macular degeneration.

METHODS

A retrospective study was designed to include consecutive cases with intermediate age-related macular degeneration associated with IRF. A multimodal imaging approach was used to confirm diagnosis of IRF in intermediate age-related macular degeneration. Multimodal imaging included color fundus photograph, fundus autofluorescence, fluorescein angiography, indocyanine green angiography, optical coherence tomography, and optical coherence tomography angiography.

RESULTS

Ten eyes of 10 patients (2 male and 8 female patients, ages 68-80 years) showing IRF in intermediate age-related macular degeneration were included in the study. The mean best-corrected visual acuity was 20/40 Snellen equivalent. Multimodal imaging including fluorescein angiography/indocyanine green angiography and optical coherence tomography demonstrated the absence of macular neovascularization in all cases; optical coherence tomography-angiography did not detect any abnormal flow signal associated with IRF. Seven of 10 patients developed IRF in correspondence of pigment epithelium detachment. Three of 10 patients presented IRF in correspondence of an area of nascent geographic atrophy.

CONCLUSION

Nonexudative intraretinal fluid in intermediate age-related macular degeneration is a novel, distinctive feature that is characterized by the presence of IRF with no evidence of macular neovascular lesions. The authors described different phenotypes of IRF in intermediate age-related macular degeneration. The definite diagnosis of this condition requires further studies with thorough application of multimodal imaging.

OCT angiography 2023 update: focus on diabetic retinopathy

Optical coherence tomography angiography (OCTA) has become part of the clinical practice and its growing applications are in continuous development. Coherently with the growing concern about the human and economic cost of diabetes, diabetic retinopathy (DR) was the most popular topic for OCTA studies in the past year. The analysis of the literature reveals that applications of OCTA in DR are in continuous growth. In particular, ultrawide field (UWF) OCTA and artificial intelligence (AI) based on OCTA images are affirming as the new frontiers of scientific research in the field. Diagnostic accuracy of AI methods based on OCTA is equal or superior to the one based on OCT methods and also bears potential to detect systemic associations. UWF OCTA is noninvasive method that is reaching similar accuracy of FA in detection of neovascularization and intraretinal microvascular abnormalities (IRMAs) and has allowed better characterization of microvascular peripherical changes in DR. Lastly, deep capillary plexus (DCP) characteristics seem to play a pivotal role in the development of diabetic macular edema (DME) and refinement of biomarkers for different phenotypes of DME and diabetic macular ischemia (DMI) is currently on its way.

Artificial intelligence in age-related macular degeneration: state of the art and recent updates

Age related macular degeneration (AMD) represents a leading cause of vision loss and it is expected to affect 288 million people by 2040. During the last decade, machine learning technologies have shown great potential to revolutionize clinical management of AMD and support research for a better understanding of the disease. The aim of this review is to provide a panoramic description of all the applications of AI to AMD management and screening that have been analyzed in recent past literature. Deep learning (DL) can be effectively used to diagnose AMD, to predict short term risk of exudation and need for injections within the next 2 years. Moreover, DL technology has the potential to customize anti-VEGF treatment choice with a higher accuracy than expert human experts. In addition, accurate prediction of VA response to treatment can be provided to the patients with the use of ML models, which could considerably increase patients' compliance to treatment in favorable cases. Lastly, AI, especially in the form of DL, can effectively predict conversion to GA in 12 months and also suggest new biomarkers of conversion with an innovative reverse engineering approach.

'Structural OCT changes distinguishing between myopic macular haemorrhages due to choroidal neovascularization and spontaneous Bruch's membrane rupture: the "myopic 2 binary reflective sign"

OBJECTIVE

To evaluate the sensitivity and specificity of structural optical coherence tomography (OCT) in comparison to fluorescein angiography (FA) and OCT angiography (OCTA) in discerning between macular haemorrhages (MH) due to myopic choroidal neovascularization (m-CNV) and idiopathic macular haemorrhage (IMH) in myopic patients and to suggest a new OCT biomarker to discern these two entities.

METHODS AND ANALYSIS

In this longitudinal retrospective study, patients affected by MH and pathological myopia were included. All patients underwent OCTA and FA to discern bleeding from m-CNV or IMH. Furthermore, all patients underwent a structural OCT and 2 expert graders evaluated the presence of the myopic 2 binary reflective sign as a biomarker to discern between IMH and bleeding from m-CNV.

RESULTS

Forty-seven eyes of 47 patients were enrolled. By means of angiographic examinations, 34 out of 47 eyes with MH (57%) were diagnosed as m-CNV, whereas 13 eyes (43%) as IMH. Using structural OCT, the graders identified the presence of the myopic 2 binary reflective sign in 13 out of 13 eyes with IMH. In 33 out of 34 cases with m-CNV, the 2 graders established the absence of the sign. This accounted for 100% of sensibility and 97% of specificity of structural OCT in discerning between MH from m-CNV and IMH.

CONCLUSION

Structural OCT can discern with good reliability between IMH and bleeding from m-CNV based on the presence/ absence of the myopic 2 binary reflective sign. This could be of paramount relevance in the clinical setting for the diagnosis and treatment of HM patients.

Long-term predictors of anti-VEGF treatment response in patients with neovascularization secondary to CSCR: a longitudinal study

PURPOSE

To identify the baseline predictors of anti-VEGF treatment response at 3 years in patients affected by choroidal neovascularization (CNV) secondary to central serous chorioretinopathy (CSCR).

METHODS

In this retrospective longitudinal study, medical records of patients diagnosed with CNV secondary to CSCR and treated using anti-VEGF injections between April 2015 and May 2020 were reviewed. The potential qualitative and quantitative predictors of treatment response were identified or measured based on the multimodal imaging examination available for each patient at the baseline, including structural OCT, fluorescein angiography (FA), indocyanine green angiography (ICGA), and OCT-angiography (OCT-A). Univariate and multivariate analyses were performed.

RESULTS

Twenty-nine eyes from 29 patients affected by CNV complicating CSCR were included in the study. At the end of the 3-year follow-up, the mean BCVA was 20/50 Snellen equivalent (0.38 ± 0.36 LogMAR), and no significant difference with baseline BCVA (0.37 ± 0.29 LogMAR) was found (p = 0.9). Twenty out of 29 eyes (69%) had active lesions at the end of the follow-up. At multivariate analysis, none of the included features was independently associated with the 3-year BCVA outcome. Pigment epithelium detachment (PED) height (ß = 0.017, p = 0.028) and outer limiting membrane (OLM) preservation at the fovea (ß = -5.637, p = 0.026) were independently associated with the CNV activity at 3 years.

CONCLUSION

PED height and OLM obliteration at the fovea might be considered baseline predictors of lesion activity at 3-year follow-up in patients with CNV secondary to CSCR treated with anti-VEGF therapy.

ARTIFICIAL INTELLIGENCE'S ROLE IN DIFFERENTIATING THE ORIGIN FOR SUBRETINAL BLEEDING IN PATHOLOGIC MYOPIA

PURPOSE

To identify salient imaging features to support human-based differential diagnosis between subretinal hemorrhage (SH) due to choroidal neovascularization (CNV) onset and SH without CNV (simple bleeding [SB]) in pathologic myopia eyes using a machine learning (ML)-based step-wise approach.

METHODS

Four different methods for feature extraction were applied: GradCAM visualization, reverse engineering, image processing, and human graders' measurements. GradCAM was performed on a deep learning model derived from Inception-ResNet-v2 trained with OCT B-scan images. Reverse engineering consisted of merging U-Net architecture with a deconvolutional network. Image processing consisted of the application of a local adaptive threshold. Available OCT B-scan images were divided in two groups: the first group was classified by graders before knowing the results of feature extraction and the second (different images) was classified after familiarization with the results of feature extraction.

RESULTS

Forty-seven and 37 eyes were included in the CNV group and the simple bleeding group, respectively. Choroidal neovascularization eyes showed higher baseline central macular thickness ( P = 0.036). Image processing evidenced in CNV eyes an inhomogeneity of the subretinal material and an interruption of the Bruch membrane at the margins of the SH area. Graders' classification performance improved from an accuracy of 76.9% without guidance to 83.3% with the guidance of the three methods ( P  = 0.02). Deep learning accuracy in the task was 86.0%.

CONCLUSION

Artificial intelligence helps identifying imaging biomarkers suggestive of CNV in the context of SH in myopia, improving human ability to perform differential diagnosis on unprocessed baseline OCT B-scan images. Deep learning can accurately distinguish between the two causes of SH.

Subclinical Angioid Streaks with Pseudodrusen: A New Phenotype of Age-Related Macular Degeneration

INTRODUCTION

To describe subclinical angioid streaks (AS) as a frequent, peculiar age-related macular degeneration (AMD) phenotype, comparing features of eyes with subclinical AS with those of eyes with AMD without AS.

METHODS

This was a retrospective, observational study. Among a patient cohort with AMD, we selected patients without known causes for AS whose eyes showed signs of angioid streaks (AS) on structural optical coherence tomography (OCT) but not on fundus examination. Selected OCT features of AS were Bruch's membrane (BM) breaks and large BM dehiscences.

RESULTS

Among 543 eyes of 274 patients with AMD (mean ± standard deviation: 82 ± 7 years), 73 eyes of 46 patients (81 ± 7 years; p = 0.432) showed AS features on OCT (OCT AS) that were not visible on fundus examination. Estimated prevalence of subclinical age-related AS was 13.4% (95% confidence interval 10.3-16.3%) in this AMD population. Fifty-three eyes (73%) with AS features were affected by peripapillary atrophy, often with a "petaloid-like" pattern, similar to typical features of AS disease. Almost all cases (97%) presented reticular pseudodrusen (RPD), with (41%) or without (59%) drusen showing a significant difference in RPD prevalence in OCT AS eyes in comparison to AMD eyes without subclinical AS using generalized estimating equations (P < 0.001). Among the 73 subclinical AS cases, 71 were affected by late AMD (57 with macular neovascularization, 14 with geographic atrophy), showing a more advanced AMD stage in comparison with AMD eyes without subclinical AS (P < 0.001). The following OCT features were disclosed: BM breaks in 100% of cases and BM dehiscences in 37%.

CONCLUSIONS

Subclinical AS in eyes with AMD is a peculiar phenotype of the disease, with features suggesting a primary involvement of Bruch's membrane and clinical similarities with mild, late-onset pseudoxanthoma elasticum.

No-Dose Photodynamic Therapy Against Half-Dose Photodynamic Therapy for Treatment of Central Serous Chorioretinopathy

INTRODUCTION

This study aimed to describe the effects of no-dose full-fluence photodynamic therapy without verteporfin (no-dose PDT) and to compare no-dose PDT with half-dose verteporfin full-fluence photodynamic therapy (HDFF PDT) for managing chronic central serous chorioretinopathy (cCSC).

METHODS

This retrospective study evaluated 11 patients with chronic recurrent CSC treated with no-dose PDT between January 2019 and March 2022. Most of these patients were also treated with HDFF PDT a minimum of 3 months before and were considered as the control group. We described the changes of best corrected visual acuity (BCVA), maximum subretinal fluid (mSRF), foveal subretinal fluid (fSRF), and choroidal thickness (CT) 8 ± 2 weeks after no-dose PDT, and we compared BVCA, mSRF, fSRF, and CT of no-dose PDT with those of the of same patients previously treated with HDFF PDT.

RESULTS

Fifteen eyes of 11 patients (10 male, mean age 54 ± 12 years) received no-dose PDT; among these, 10 eyes of 8 patients (7 male, mean age 53 ± 12 years) also received HDFF PDT. Three eyes showed complete resolution of fSRF after no-dose PDT. No significant differences were disclosed between treatment with and without verteporfin comparing BCVA, mSRF, fSRF, and CT at baseline and 8 ± 2 weeks from the treatment (p > 0.05 in all analyses).

CONCLUSION

BVCA and CT significantly improved after no-dose PDT. Short-term functional and anatomical treatment outcomes for cCSC were similar for HDFF PDT and no-dose PDT. We hypothesize that the potential benefits of no-dose PDT may arise from thermal elevation that triggers and enhances photochemical activities by endogenous fluorophores, activating a biochemical cascade response that rescues/replaces sick, dysfunctional retinal pigment epithelial (RPE) cells. Results of this study suggest the potential value of a prospective clinical trial to evaluate no-dose PDT for managing cCSC, especially when verteporfin is contraindicated or unavailable.

The retinal neurovascular coupling is impaired in men with vasculogenic erectile dysfunction

The aim of this study was to study the retinal vessels in patients affected by vasculogenic erectile dysfunction (ED), using dynamic vessel analyzer (DVA). Patients with vasculogenic ED and control subjects were prospectively enrolled to undergo a complete urological and ophthalmologic evaluation, including DVA and structural optical coherence tomography (OCT). The main outcome measures were: (1) arterial dilation; (2) arterial constriction; (3) reaction amplitude (the difference between arterial dilation and constriction); and, (4) venous dilation. Thirty-five patients with ED and 30 male controls were included in the analysis. Mean ± SD age was 52.0 ± 10.8 years in the ED group and 48.1 ± 16.3 years in the control group (p = 0.317). In the dynamic analysis, the arterial dilation was lower in the ED group (1.88 ± 1.50%), as compared with the control group (3.70 ± 1.56%, p < 0.0001). Neither arterial constriction nor venous dilation differed between groups. The reaction amplitude was decreased in ED patients (2.40 ± 2.02%, p = 0.023), compared to controls (4.25 ± 2.20%). In the Pearson correlation analysis, the ED severity, was directly correlated with both reaction amplitude (R = .701, p = 0.004) and arterial dilation (R = .529, p = 0.042). In conclusion, subjects with vasculogenic ED are featured by a significant dysfunction of the retinal neurovascular coupling, which is inversely correlated with ED severity.

The state-of-the-art pharmacotherapeutic management of neovascular age-related macular degeneration

INTRODUCTION

Age-related macular degeneration (AMD) is a major cause of central visual loss in the developed world. Although the pathogenesis is not fully understood, vascular endothelial growth factor (VEGF) is considered the most important growth factor involved in angiogenesis and exudation in neovascular AMD eyes. Advances in anti-VEGF agents have changed the treatment approach for wet AMD, allowing better outcomes in visual acuity and retinal anatomy.

AREAS COVERED

The present review describes the main pharmacological and clinical characteristics of anti-VEGF drugs, focusing firstly on the molecules commonly in use and then on the new candidate therapies. We performed a comprehensive literature search using the PubMed database from 1 January 1993 to 1 June 2022, with search terms including anti-VEGF, biosimilar, neovascular macular degeneration, AMD, and safety.

EXPERT OPINION

The management of AMD is still onerous for both the physician and patient due to the great number of required injections. Current research is underway to resolve not only the economic burden but also the discomfort of patients, aiming to develop a drug with a different or a multiple target, increasing the potency whilst maintaining a good safety profile. Furthermore, clinical research is currently investigating different forms of drug administration.

Individual vs. combined imaging modalities for diagnosing neovascular central serous chorioretinopathy

PURPOSE

To assess the diagnostic accuracy of individual and combined imaging modalities compared with multimodal imaging for the detection of choroidal neovascularization (CNV) in central serous chorioretinopathy (CSC).

METHODS

We analyzed patients with CSC with and without CNV who had indocyanine green angiography (ICGA), structural optical coherence tomography (OCT), and OCT angiography (OCTA) obtained on the same day. The presence of CNV was determined using multimodal imaging by a senior retina specialist (i.e., diagnostic reference). Individual and combined (i.e., ICGA + structural OCT) imaging modalities were then graded by two expert readers for the presence of CNV. Sensitivity, specificity, positive (PPV), and negative (NPV) predictive values were computed for individual and combined imaging modalities relative to the diagnostic reference.

RESULTS

CNV was detected in 17 eyes in 17 out of 33 CSC patients according to the reference standard. Using ICGA, the identification of CNV had a sensitivity of 66.7%, specificity of 66.7%, PPV of 70.6%, and NPV of 62.5%. Structural OCT had the following diagnostic accuracy values: 83.3% of sensitivity, 53.3% of specificity, 68.1% of PPV, and 72.7% of NPV. Using OCTA, CNV was graded to be present with a sensitivity of 77.8%, specificity of 86.7%, PPV of 87.5%, and NPV of 76.5%. The combination of ICGA and structural OCT granted the identification of CNV with a sensitivity of 83.3%, specificity of 86.7%, PPV of 88.2%, and NPV of 81.3%.

CONCLUSIONS

OCTA has an elevated diagnostic accuracy in identifying CSC-associated CNV, though a combination of ICGA and structural OCT has a comparable diagnostic efficiency.

OCT Predictors of 3-Year Visual Outcome for Type 3 Macular Neovascularization

PURPOSE

To identify baseline OCT predictors of the 3-year visual outcome for type 3 (T3) macular neovascularization (MNV) secondary to age-related macular degeneration (AMD) treated by anti-vascular endothelial growth factor (VEGF) therapy.

DESIGN

Retrospective longitudinal study.

PARTICIPANTS

Forty eyes of 30 patients affected by exudative treatment-naive T3 MNV were enrolled.

METHODS

Baseline best-corrected visual acuity (BCVA) and several baseline OCT features were assessed and included in the analysis. Univariate and multivariate analyses served to identify risk factors associated with the 3-year BCVA.

MAIN OUTCOME MEASURES

Baseline OCT features that are associated with bad or good visual outcomes of T3 MNV treated by anti-VEGF injections.

RESULTS

Mean baseline BCVA was 0.34 ± 0.28 logarithm of the minimum angle of resolution (LogMAR), which significantly decreased to 0.52 ± 0.37 LogMAR at the end of the 3-year follow-up (P = 0.002). In the univariate analysis, the following baseline features were associated with the 3-year BCVA outcome: baseline BCVA (P = 0.004), foveal involvement of exudation (P = 0.004), and presence of subretinal fluid (SRF; P = 0.004). In the multivariate model, baseline BCVA (P = 0.032), central macular thickness (P = 0.036), number of active T3 lesions (P = 0.034), and presence of SRF (P = 0.008) were associated with the 3-year BCVA outcome. Interestingly, 3-year BCVA was significantly lower in 19 eyes with SRF at the baseline (0.69 ± 0.42 LogMAR) than 21 eyes without SRF (0.37 ± 0.24 LogMAR; P = 0.004).

CONCLUSION

We identified structural OCT features associated with BCVA outcome after 3-year treatment with anti-VEGF injections. In contrast to previous studies on neovascular AMD, in our series, the presence of SRF at baseline was the most significant independent negative predictor of functional outcomes. Current findings may be employed to identify less favorable T3 patterns potentially deserving a more intensive treatment.

Long-Term Visual Outcomes and Morphologic Biomarkers of Vision Loss in Eyes With Diabetic Macular Edema Treated With Anti-VEGF Therapy

PURPOSE

To analyze the morphological characteristics and long-term visual outcomes in eyes with diabetic retinopathy (DR) and diabetic macular edema (DME) treated with anti-vascular endothelial growth factor (anti-VEGF) therapy.

DESIGN

Retrospective clinical cohort study.

METHODS

Patients with a long-term follow-up and evidence of resolved DME in at least 1 visit (study visit) after 5 years of follow-up after the initiation of anti-VEGF therapy were included. At the study visit, structural optical coherence tomography (OCT) scans were reviewed for qualitative features reflecting a distress of the neuroretina or retinal pigment epithelium (RPE). A quantitative topographical assessment of the inner and outer retinal thicknesses was also provided.

RESULTS

A total of 61 eyes (50 patients) were included and were divided into 2 subgroups according to visual acuity (VA) at the study visit, yielding a group of 24 eyes with a VA <20/40 ("poor/intermediate vision" group), and 37 eyes with a VA ≥20/40 ("good vision" group). The external limiting membrane (ELM) and RPE bands were more frequently disrupted or absent in the poor/intermediate vision group (P = .003 and P = .019). Similarly, disorganization of retinal inner layers was more prevalent in the poor/intermediate vision group (P = .013). The foveal and parafoveal outer retinal thicknesses were reduced in eyes with poor/intermediate vision (P = .022 and P = .044). Multivariate stepwise linear regression analysis demonstrated that VA was associated with appearances of the RPE and ELM (P < .0001 and P = .048), foveal and parafoveal outer retinal thicknesses (P = .046 and P = .035).

CONCLUSIONS

Modifications in the outer retina and RPE represent OCT biomarkers of long-term visual outcomes in eyes with DME treated with anti-VEGF.

CHOROIDAL VASCULARITY INDEX IS ASSOCIATED WITH GEOGRAPHIC ATROPHY PROGRESSION

PURPOSE

To investigate the correlation between choroidal vascularity index and the enlargement of geographic atrophy (GA) lesion secondary to age-related macular degeneration during the 2-year follow-up.

METHODS

In this longitudinal observational study, 26 eyes (26 patients, mean age 75.7 ± 8.8 years) affected by GA were included. Choroidal vascularity index was calculated in the subfoveal 3000-µm area. The main outcome measure included correlation analysis between baseline choroidal vascularity index and the rate of GA enlargement.

RESULTS

During the 2-year follow-up, the mean GA area increased from 6.99 ± 5.28 mm2 to 10.69 ± 6.61 mm2(P < 0.001), accounting for a growth rate of 0.35 ± 0.20 and 0.31 ± 0.17 mm/year after the square root transformation in the first and second year of follow-up, respectively. Stromal choroidal area significantly decreased during the 2-year follow-up (P = 0.002). Interestingly, there was a significant correlation between the baseline choroidal vascularity index and the rate of GA enlargement (r=-0.432, P = 0.027) and between stromal choroidal area and the rate of GA enlargement (r = 0.422, P = 0.032). No other significant relationship was disclosed among choroidal parameters with the rate of GA enlargement.

CONCLUSION

Choroidal vascularity index impairment is strictly related to the rate of GA enlargement during the 1-year and 2-year follow-up in patients affected by GA. For this reason, choroidal vascularity index could be considered a predictor of GA progression in the clinical setting, and it could be considered as a new potential biomarker in the efficacy evaluation of new GA interventions.

Changes in Macular Perfusion After ILUVIEN® Intravitreal Implant for Diabetic Macular Edema: An OCTA Study

Introduction

The aim of this study was to investigate changes in macular perfusion in patients affected by diabetic macular edema (DME) and treated with ILUVIEN® (fluocinolone acetonide intravitreal implant) 0.19 mg using optical coherence tomography angiography (OCTA).

Methods

This was a retrospective cohort study that included patients aged > 18 years with type 2 non-proliferative diabetic retinopathy (DR) and DME at baseline. All patients were treated with the ILUVIEN® implant. A minimum of two 6 × 6-mm OCTA scans were required to ensure that all cases had a baseline OCTA and an OCTA performed at 4 months of follow-up. Qualitative and quantitative comparisons were performed.

Results

Ten eyes from ten subjects were included in the analysis. Mean (± standard deviation) age of the study cohort was 57.1 ± 8.3 years. Mean parafoveal perfusion density (PD) at baseline was 64.1 ± 1.8% at baseline, increasing to 66.1 ± 2.9% (p = 0.013) at the 4-month follow-up visit. Mean parafoveal PD at baseline was 64.4 ± 2.1%, increasing to 65.2 ± 2.6% (p = 0.024) after 4 months. In the qualitative assessment, 60 regions (10 areas for each subject) were graded to assess changes in retinal perfusion between the baseline and follow-up visits. This assessment revealed that 24 regions (40.0%) were characterized by a qualitative increase in perfusion after treatment, while 22 (36.7%) and 14 (23.3%) regions were featured by a stability and reduction in retinal perfusion, respectively.

Conclusion

OCTA analysis detects improvements in macular perfusion after treatment with ILUVIEN®. This improvement in macular perfusion may be associated with corticosteroid-related beneficial effects on leukostasis.

Volume rendered 3D OCTA assessment of macular ischemia in patients with type 1 diabetes and without diabetic retinopathy

The aim of this study was to measure macular perfusion in patients with type 1 diabetes and no signs of diabetic retinopathy (DR) using volume rendered three-dimensional (3D) optical coherence tomography angiography (OCTA). We collected data from 35 patients with diabetes and no DR who had OCTA obtained. An additional control group of 35 eyes from 35 healthy subjects was included for comparison. OCTA volume data were processed with a previously presented algorithm in order to obtain the 3D vascular volume and 3D perfusion density. In order to weigh the contribution of different plexuses' impairment to volume rendered vascular perfusion, OCTA en face images were binarized in order to obtain two-dimensional (2D) perfusion density metrics. Mean ± SD age was 27.2 ± 10.2 years [range 19-64 years] in the diabetic group and 31.0 ± 11.4 years [range 19-61 years] in the control group (p = 0.145). The 3D vascular volume was 0.27 ± 0.05 mm³ in the diabetic group and 0.29 ± 0.04 mm³ in the control group (p = 0.020). The 3D perfusion density was 9.3 ± 1.6% and 10.3 ± 1.6% in diabetic patients and controls, respectively (p = 0.005). Using a 2D visualization, the perfusion density was lower in diabetic patients, but only at the deep vascular complex (DVC) level (38.9 ± 3.7% in diabetes and 41.0 ± 3.1% in controls, p = 0.001), while no differences were detected at the superficial capillary plexus (SCP) level (34.4 ± 3.1% and 34.3 ± 3.8% in the diabetic and healthy subjects, respectively, p = 0.899). In conclusion, eyes without signs of DR of patients with diabetes have a reduced volume rendered macular perfusion compared to control healthy eyes.

Choroidal Vascularity Index in Different Cohorts of Dry Age-Related Macular Degeneration

Purpose

The purpose of this study was to investigate the choroidal luminal and interstitial stromal alterations using choroidal vascularity index (CVI) among different cohorts of dry age-related macular degeneration (dAMD) compared to healthy subjects.

Methods

Four distinct cohorts were collected: three different cohorts of patients with dAMD (i.e. drusen, reticular pseudodrusen [RPD], and geographic atrophy [GA]) and an age-matched cohort of healthy subjects (controls). CVI (the ratio between the luminal choroidal area [LCA] and the total choroidal area [TCA]) was calculated in the subfoveal 1000 µm area.

Results

One hundred twenty eyes (from 120 patients) were included (30 eyes in each cohort). The mean age was 76.6 ± 7.1 years. No statistical differences were disclosed in terms of age, axial length, and central macular thickness among study groups. TCA showed a different distribution among the four cohorts (P = 0.003), mainly due to the LCA changes (P = 0.001). Interestingly, CVI showed a different distribution among the four cohorts (P < 0.001). RPD showed a lower CVI in comparison to controls (P = 0.040), whereas GA showed a lower CVI in comparison to drusen, RPD, and controls (P = 0.001, P = 0.046, and P < 0.001, respectively).

Conclusions

Different cohorts of dAMD are characterized by different impairments of the choroidal vascular and stromal components, reflecting different degrees of AMD severity.

Translational Relevance

CVI provides insights for better understanding the pathogenesis of AMD.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY ASSESSMENT OF THE DIABETIC MACULA: A Comparison Study Among Different Algorithms

PURPOSE

To assess the impact of histogram adjustments and binarization thresholding selection on quantitative measurements of diabetic macular ischemia using optical coherence tomography angiography (OCTA).

METHODS

Patients with diabetic retinopathy (DR) who had swept-source OCTA imaging obtained were enrolled. An additional group of 15 healthy control subjects was included for comparison. Previously used brightness/contrast changes and binarization thresholds were applied to original OCTA images to obtain and compare different binarized images. Qualitative and quantitative comparisons were performed.

RESULTS

Thirty patients with DR (30 eyes) were included in the analysis. Fifteen eyes displayed the presence of diabetic macular edema. Qualitative grading revealed that binarized images obtained using a global threshold had better quality compared with local or multistep thresholds. The "median" filter was most frequently graded as the histogram adjustment resulting in binarized images with best quality. In the quantitative analysis, local thresholds tended to generate higher values of measured metrics. Differences in OCTA metrics between global and local thresholds were associated with presence of diabetic macular edema and signal strength index value. In the comparison between healthy and DR eyes, differences in OCTA metrics were significantly affected by binarization threshold selection.

CONCLUSION

Quantitative OCTA parameters may be significantly influenced by strategies to quantify macular perfusion. Image quality and presence of macular edema can significantly impact OCTA-derived quantitative vascular measurements and differences between global and local binarization thresholds. These findings highlight the importance of consistent strategies to reliably generate quantitative OCTA metrics in patients with DR.

USING THREE-DIMENSIONAL OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY METRICS IMPROVES REPEATABILITY ON QUANTIFICATION OF ISCHEMIA IN EYES WITH DIABETIC MACULAR EDEMA

PURPOSE

Two-dimensional (2D) optical coherence tomography angiography (OCTA) is known to be prone to segmentation errors, especially in pathologic eyes. Therefore, our aim was to systematically compare intrasession repeatability between repeated scans for 2D and three-dimensional (3D) OCTA metrics in quantifying retinal perfusion in eyes with diabetic macular edema.

METHODS

Diabetic patients with diabetic retinopathy and diabetic macular edema who had two consecutive OCTA imaging scans obtained during the same visit were retrospectively included. A previously validated algorithm was applied to OCTA volume data to measure the 3D vascular volume and perfusion density. Optical coherence tomography angiography en face images were also processed to obtain 2D perfusion density metrics.

RESULTS

Twenty patients (20 eyes) with diabetic retinopathy and diabetic macular edema were included. The intraclass correlation coefficient ranged from 0.591 to 0.824 for 2D OCTA metrics and from 0.935 to 0.967 for 3D OCTA metrics. Therefore, compared with the 2D OCTA analysis, the intraclass correlation coefficients of the 3D OCTA analysis were higher (without overlapping of the 95% confidential intervals). Similarly, the coefficient of variation (ranging from 2.2 to 4.2 for 2D OCTA metrics and from 1.9 to 2.0 for 3D OCTA metrics) indicated that the 3D OCTA-based quantifications had the highest interscan intrasession agreements. Differences in interscan 2D OCTA metrics' values were associated with average macular volume.

CONCLUSION

Three-dimensional OCTA metrics have higher values of intrasession repeatability, as compared with 2D OCTA metrics. The latter finding seems to be related to the high rate of segmentation errors occurring in diabetic macular edema eyes.

Longitudinal assessment of type 3 macular neovascularization using three-dimensional volume-rendering OCTA

OBJECTIVE

To investigate the evolution of treatment-naive type 3 macular neovascularization (MNV) undergoing anti-vascular endothelial growth factor (VEGF) treatment through volume rendered three-dimensional (3D) optical coherence tomography angiography (OCTA).

DESIGN

Retrospective observational study.

PARTICIPANTS

Patients with type 3 MNV and age-related macular degeneration (AMD).

METHODS

Included subjects had three loading injections of an anti-VEGF agent. The OCTA volume data at baseline and follow-up were processed with a previously published algorithm in order to obtain a volume-rendered representation of type 3 MNV. Progressive changes in type 3 lesions were analyzed via 3D OCTA volume rendering.

RESULTS

A total of 14 treatment-naive eyes with type 3 MNV from 11 AMD patients (7 females) were included. At both baseline and follow-up visits, a type 3 MNV complex was identifiable. Each complex was composed of a mean number of 2.5 ± 0.7 vascular branches at baseline and 1.4 ± 0.6 at the follow-up visit (p < 0.0001). The mean changes in central macular thickness and visual acuity were significantly correlated with modifications in the number of type 3 MNV branches (ρ = -0.533, p = 0.049, and ρ = -0.581, and p = 0.040, respectively).

CONCLUSIONS

This study demonstrated that type 3 lesions do not disappear completely after loading treatment, as indicated previously by histopathologic studies. Importantly, quantitative volume changes in type 3 lesions are directly associated with treatment response.

Three-year OCT predictive factors of disease recurrence in eyes with successfully treated myopic choroidal neovascularisation

PURPOSE

To assess the relationship of demographics, clinical characteristics and structural optical coherence tomography (OCT) findings to disease recurrence in a cohort of patients with newly diagnosed myopic choroidal neovascularisation (CNV) METHODS: In this retrospective, longitudinal study, a total of 64 participants (64 eyes) with successfully treated myopic CNV had obtained resolution of exudation after treatment (study baseline) and with 3 years of regular follow-ups. Several baseline OCT qualitative features and quantitative measurements were assessed at baseline and included in the analysis. Main outcome measures included incidence of disease recurrence and HR for demographics, clinical characteristics and OCT risk factors.

RESULTS

At month 36, 40 eyes (62.5%) developed disease recurrence (active CNV). Multivariate linear regression analysis revealed that final visual acuity (dependent variable) was associated with visual acuity at the first visit after complete resolution of exudation (p<0.0001), baseline size of patchy atrophy (p=0.010), baseline subfoveal choroidal thickness (p=0.008), baseline maximum CNV height and width (p=0.011 and p=0.003) and recurrence of CNV exudation (p=0.007). The following factors were associated with an increased risk of disease recurrence: size of patchy atrophy had an HR of 1.14 (95% CI 1.01 to 1.29; p=0.036); maximum CNV width had an HR of 1.02 (95% CI 1.01 to 1.04; p<0.0001).

CONCLUSION

We identified OCT risk factors for the disease recurrence in eyes with successfully treated myopic CNV. Assuming that disease recurrence is a sight-threatening event, our findings may help in the identification of high-risk patients and eventually ameliorate their outcome.

OCT Risk Factors for 3-Year Development of Macular Complications in Eyes With "Resolved" Chronic Central Serous Chorioretinopathy

PURPOSE

To assess the relationship between demographics, clinical characteristics, and structural optical coherence tomography (OCT) findings and the development of sight-threatening macular complications (choroidal neovascularization [CNV], large areas of retinal pigment epithelium [RPE] atrophy, and cystoid macular degeneration [CMD]) in a cohort of eyes with "resolved" chronic central serous chorioretinopathy (CSC) at study baseline.

DESIGN

Retrospective cohort study.

METHODS

In this study, a total of 71 eyes with "resolved" (absence of subretinal fluid) chronic CSC at baseline and 36 months of regular follow-up examinations were retrospectively enrolled. Structural OCT scans were reviewed. Baseline OCT qualitative features reflecting distress of the neuroretina, RPE, or choroid were assessed and included ellipsoid zone discontinuity, outer nuclear layer (ONL) thinning; presence of hyper-reflective intraretinal foci; dome-shaped pigment epithelium detachment (PED); hyper-reflective flat, irregular PED; hyporeflective flat, irregular PED; and inner choroidal attenuation. OCT images obtained at follow-up visits were also reviewed for development of macular complications (CNV, large areas of RPE atrophy [at least 250 μm in diameter], and CMD). Main outcome measurements included incidence of macular complications and hazard ratio (HR) for demographics, clinical characteristics, and OCT risk factors.

RESULTS

At month 36, 20 eyes (28.2%) developed macular complications. Nine eyes (12.7%) displayed CNV, 9 eyes (12.7%) had large areas of RPE atrophy, and 2 eyes (2.8%) developed cystoid macular degeneration. The following factors were associated with an increased risk of development of CNV: intraretinal hyper-reflective foci had an HR of 11.58 (95% confidence interval [CI]: 1.10-37.24; P = .040); inner choroidal attenuation had an HR of 9.66 (95% CI: 1.07-22.34; P = .043); and the presence of macular complications in the fellow eye had an HR of 20.17 (95% CI: 1.34-39.41; P = .030). Factors associated with the development of RPE atrophy were also identified: ONL thinning had an HR of 13.47 (95% CI: 1.10-39.86; P = .042); dome-shaped PED had an HR of 21.40 (95% CI: 1.50-41.10; P = .031); and inner choroidal attenuation had an HR of 13.20 (95% CI: 1.07-39.32; P = .044).

CONCLUSIONS

OCT risk factors were identified for the development of macular complications in eyes with chronic CSC. Findings may help in the identification of high-risk patients.

Peripapillary hyperreflective ovoid mass-like structures (PHOMS): OCTA may reveal new findings

PURPOSE

Peripapillary hyperreflective ovoid mass-like structures (PHOMS) are novel and not well characterized findings occurring in several disorders of the optic nerve. The aim of this study is to present two cases of tilted disc syndrome (TDS) and one case with optic disc drusen undergoing a multimodal imaging approach.

METHODS

In this case series, a qualitative evaluation of the OCTA findings in regions with PHOMS was performed.

RESULTS

Structural OCT revealed the presence of PHOMS. OCTA identified the presence of a vascular complex within this hyperreflective structure.

CONCLUSIONS

Assuming that PHOMS are thought to correspond to herniating nerve fibers or be secondary to axoplasmic stasis, this vascular complex may represent a displacement of the deeper vessels deputed at the irroration of the optic nerve into the retina or, alternatively, might be secondary to an increase in vascular endothelial growth factor (VEGF) levels and a subsequent development of neovessels.

Subthreshold laser treatment for reticular pseudodrusen secondary to age-related macular degeneration

There is a lack of treatment aimed at the regression of reticular pseudodrusen (RPD) secondary to age-related macular degeneration (AMD). The aim of this prospective, pilot study is to evaluate the safety and short-term efficacy of subthreshold laser treatment (SLT) in patients affected by RPD secondary to dry AMD (dAMD). Twenty eyes of 20 patients (mean age 78.4 ± 6.8 years) with RPD secondary to dAMD were prospectively enrolled. All patients were treated in an extrafoveal area of 1.27 mm² using end-point management yellow subthreshold laser and followed for 3 months. Best-corrected visual acuity was 0.140 ± 0.09 LogMAR at the baseline and no changes were observed during the follow-up (p = 0.232). No significant worsening was disclosed before and after the treatment analyzing the macular sensitivity of the treated area (p = 0.152). No topical and/or systemic side effects were disclosed during the 3-month follow-up. The distribution among the RPD stages changed after the treatment (p < 0.001). In detail, in the treated area, we observed a significant increase in the number of Stage 1 RPD during the follow-up (p = 0.002), associated with a significant decrease of Stage 3 RPD (p = 0.020). Outer nuclear layer (ONL) thickness analysis showed a significant increase after the treatment associated with RPD regression (p = 0.001). End-point management SLT appears a safe treatment for RPD secondary to dAMD, showing short-term safety outcomes. Our results suggest that SLT could be effective in inducing a RPD regression in terms of RPD stage and ONL thickening.

Treatment-naïve quiescent macular neovascularization secondary to AMD: The 2019 Young Investigator Lecture of Macula Society

PURPOSE

To analyze different clinical and anatomical features in treatment-naïve non-exudative macular neovascularizations (MNVs) secondary to age-related macular disease (AMD).

METHODS

In this retrospective longitudinal study with a minimum follow-up of 1 year, 31 eyes of 28 consecutive AMD patients (mean age 75 ± 9 years) with treatment-naïve non-exudative MNV were enrolled. Patients were divided in: short-term activated MNV group (exudation before 6-month) and quiescent MNV group (per definition no exudation during a minimum 6-month follow-up) showing no or late activation during follow-up (persistently quiescent and long-term activated MNV group, respectively).

RESULTS

During the follow-up (mean duration: 22 ± 9 months) four eyes (13%) showed exudation before 6-month follow-up (short-term activated MNV group), whereas 21 eyes (68%) did not develop signs of exudation (persistently quiescent group), and six eyes (19%) developed exudation after the minimum 6-month follow-up (long-term activated MNV group). Monthly MNV growth rate was significantly higher in the short-term activated MNV group (growth rate of 13.30%/month), vs persistently quiescent MNV group (0.64%/month, p < 0.001) and long-term activated quiescent MNV group (1.07%/month, p < 0.001). Furthermore, at the baseline, perfusion density of short-term activated MNV group was significantly greater in comparison to persistently quiescent MNV group (p = 0.001) and long-term activated MNV group (p = 0.106).

CONCLUSION

We reported two different patterns for subclinical MNVs: subclinical MNVs characterized by short-term activation which could represent simply a pre-exudative stage in the development of an ordinary type 1 MNV, and quiescent MNVs characterized by low rate of growth and possible long-term activation. Analysis of OCT-A features may predict short-term activation for subclinical MNV but no features could predict the long-term activation.

Photoreceptor alteration in intermediate age-related macular degeneration

The aim of this study was to analyze photoreceptor alterations occurring in eyes with intermediate age-related macular degeneration (AMD) and to investigate their associations with choriocapillaris (CC) flow. In this retrospective case-control study, we collected data from 35 eyes with intermediate AMD from 35 patients who had swept source optical coherence tomography structural and angiography imaging obtained. A control group of 35 eyes from 35 healthy subjects was included for comparison. Our main outcome measure for comparison between groups was the normalized reflectivity of en face image segmented at the ellipsoid zone (EZ) level, which was calculated to quantify the photoreceptor damage. OCTA metrics to quantify CC flow signal were also computed. These metrics were measured in a circle centered on the fovea and with a diameter of 5 mm. In intermediate AMD eyes, the macular area occupied by drusen was identified. Therefore, the EZ reflectivity and CC flow signal were separately measured in regions without drusen ("drusen-free" region). Measurements were generated using previously published algorithms. Mean ± SD age was 74.1 ± 6.8 years in the intermediate AMD group and 72.1 ± 6.0 years in the control group (p = 0.206). The normalized EZ reflectivity was 0.76 ± 0.10 in the intermediate AMD group and 0.85 ± 0.08 in the control group (p < .0001). In the "drusen-free" region, the normalized EZ reflectivity was 0.77 ± 0.10 (p < .0001  vs. healthy controls) and was positively correlated with the CC flow signal density (ρ = - 0.340 and p = 0.020). In conclusion, eyes with intermediate AMD exhibit a diffuse reduced EZ normalized reflectivity, and this reduction is correlated with CC flow signal in the regions without drusen. This study supports the concept of the damage of the unit comprised of photoreceptor, CC, and intervening tissues as an early event in AMD.

Guidelines on Optical Coherence Tomography Angiography Imaging: 2020 Focused Update

Optical coherence tomography angiography (OCTA) has significantly expanded our knowledge of the ocular vasculature. In this review, we provide a discussion of the fundamental principles of OCTA and the application of this imaging modality to study the retinal and choroidal vessels. These guidelines are focused on 2020, and include updates since the 2019 publication. Importantly, we will comment on recent findings on OCTA technology with a special focus on the three-dimensional (3D) OCTA visualization.

Multimodal Imaging to Detect in vivo Responses to Aflibercept Therapy in a Mouse Model of Type 3 Neovascularization

PURPOSE

The aim of this study was to characterize the response to aflibercept in a mouse model of type 3 neovascularization, the neoretinal vascularization (NRV) 2 mouse line.

METHODS

Twelve NRV2 mice were assigned to one of the following groups: (1) 6 mice were injected with aflibercept 3 µg/g at postnatal day (P) 15 ("aflibercept" group), and (2) the remaining 6 mice did not receive any treatment ("placebo" group). The mice were examined at P30 and P44.

RESULTS

The NRV mice's retinas were characterized by regions of depigmentation that were topographically associated with hyperfluorescent lesions seen on fluorescein angiography (FA) images. On optical coherence tomography images, intraretinal neovascularizations were visualized as hyperreflective lesions mainly localized within the outer plexiform and outer nuclear layers. The average number of intraretinal neovascular lesions visualized on FA at P30 was 5.0 ± 2.2 in the aflibercept group and 20.7 ± 2.4 in the placebo group (p < 0.0001). At P44, the average number of intraretinal lesions was still lower in the aflibercept group, although this difference was not statistically significant (p = 0.088).

CONCLUSION

Aflibercept therapy was effective in inhibiting pathologic angiogenesis in the NRV2 mouse model. However, the successive treatment washout resulted in an increase in the number of lesions.

TriPla Regimen: A new treatment approach for patients with neovascular age-related macular degeneration in the COVID-19 "era"

In the last months, a rapidly increasing number of people have been infected with severe acute respiratory syndrome coronavirus 2, the virus causing coronavirus disease 2019 (COVID-19). Due to the risk of cross-infections, the number of visits and injections was dramatically reduced in the last months, and the time between visits has been rescheduled from every 15 to 45 min, significantly impairing the total number of available visits. Although continuity of care has been allowed, a series of measures to diminish the risk of contamination need to be adopted until the end of this pandemic outbreak, which may persist until the development of an effective vaccine. For these reasons, we have introduced a new treatment regimen that is aimed at reducing the number of in-person visits and achieving continuity of treatment. This regimen is named "Triple and Plan" (TriPla). The main advantage of the TriPla regimen is to reduce the number of visits of patients in comparison to the pro re nata and treat and extend regimen. Using the TriPla regimen, the risk of contamination would be reduced. Furthermore, by reducing the number of scheduled visits, physicians could guarantee an adequate number of examinations for each patient, lengthening the interval between visits, and reducing the risk of cross-infections.

Short-term outcomes of patients with neovascular exudative AMD: the effect of COVID-19 pandemic

PURPOSE

To estimate the impact of delayed care during the coronavirus disease 2019 (COVID-19) pandemic on the outcomes of patients with neovascular age-related macular degeneration (AMD).

METHODS

Consecutive patients with diagnosis of neovascular AMD were consecutively enrolled between March 9, 2020, and June 12, 2020, (during and immediately after the Italian COVID-19 quarantine). During the inclusion (or pandemic) visit (V₀), patients received a complete ophthalmologic evaluation, including optical coherence tomography (OCT). Best-corrected visual acuity (BCVA) and OCT findings from the two preceding visits (V_-1 and V_-2) were compared with data at V₀.

RESULTS

One-hundred patients (112 eyes) were enrolled in this study. The time interval between following visits was 110.7 ± 37.5 days within V₀ and V_-1 and 80.8 ± 39.7 days within V_-1 and V_-2, respectively (P < 0.0001). BCVA was statistically worse at the V₀ visit as compared with the immediately preceding (V_-1) visit (0.50 ± 0.43 LogMAR and 0.45 ± 0.38 LogMAR at the V₀ and V_-1 visits, respectively; P = 0.046). On structural OCT, 91 out of 112 (81.2%) neovascular AMD eyes displayed the evidence of exudative disease activity at the V₀ visit, while 77 (68.7%) eyes exhibited signs of exudation at the V_-1 visit (P = 0.022). No differences in terms of BCVA and OCT findings were detected between the V_-1 and V_-2 visits. In multiple regression analysis, the difference in BCVA between V₀ and V_-1 visits was significantly associated with the interval time within these two visits (P = 0.026).

CONCLUSION

The COVID-19 pandemic-related postponement in patient care proved to be significantly associated with worse short-term outcomes in these patients.

Quantification of diabetic macular ischemia using novel three-dimensional optical coherence tomography angiography metrics

We applied three-dimensional (3D) analysis to optical coherence tomography angiography (OCTA) to measure macular ischemia in eyes affected by non-proliferative diabetic retinopathy (DR). A previously validated algorithm was applied to OCTA data in order to obtain 3D visualization of the retinal vasculature. Successively, a global thresholding algorithm was applied and two novel quantitative metrics were introduced: 3D vascular volume and 3D perfusion density. Two-dimensional (2D) OCTA metrics were also obtained with different binarization thresholds for comparison. Of the 30 patients included, 15 were diagnosed with DR and 15 were controls. The 3D vascular volume and 3D perfusion density were reduced in DR eyes (P < .0001). The 2D variables also significantly differ between groups. The 3D perfusion density had the highest area under the receiver operating characteristic curve (0.964) among tested variables. Assessing quantitative perfusion using 3D analysis is reliable and promising, and with an elevated diagnostic efficacy in identifying DR eyes.

Impact of COVID-19 on outpatient visits and intravitreal treatments in a referral retina unit: let's be ready for a plausible "rebound effect"

Purpose

To quantify the shrinking in outpatient and intravitreal injections’ volumes in a tertiary referral retina unit secondary to virus causing coronavirus disease 2019 (COVID-19).

Methods

In this retrospective cross-sectional study, we reviewed the charts of all patients who had a visit at a medical retina referral center during the Italian quarantine (from 9th of March 2020 to 3rd of May 2020). Number and characteristics of these data were compared with data from the same period in 2019 (from 9th of March 2019 to 3rd of May 2019).

Results

In the 2019 study period, there were 303 patients attending clinic (150 males, 153 females). In the 2020 study period, patients decreased to 75 (48 males, 27 females; P = 0.022 comparing gender prevalence between the two periods) with an overall reduction of 75.2%. Mean ± SD age was 71.4 ± 14.3 years (range 25–93 years) in the 2019 study period and 66.7 ± 13.1 years (range 32–91 years) in the 2020 study period (P = 0.005). The largest drop in outpatient volume was recorded in AMD patients (− 79.9%). Regarding the intravitreal treatments, there were 1252 injections in the 2019 period and 583 injections in the 2020 period (− 53.6% in injections). The drop in intravitreal treatments was larger in patients with posterior uveitis, retinal vein occlusion, and diabetes (− 85.7%, − 61.9%, and − 59.6%, respectively).

Conclusion

The volume of outpatient visits and intravitreal injections declined during the COVID-19 quarantine. The short- and long-term impacts are that routine in-person visits and intravitreal injections are expected to increase after the quarantine and, even more, after the pandemic.

Nonmydriatic widefield retinal imaging with an automatic white LED confocal imaging system compared with dilated ophthalmoscopy in screening for diabetic retinopathy

PURPOSE

To compare nonmydriatic montage widefield images with dilated fundus ophthalmoscopy for determining diabetic retinopathy (DR) severity.

MATERIALS AND METHODS

In this prospective, observational, cross-sectional study, patients with a previous diagnosis of diabetes and without history of diabetes-associated ocular disease were screened for DR. Montage widefield imaging was obtained with a system that combines confocal technology with white-light emitting diode (LED) illumination (DRSplus, Centervue, Padua, Italy). Dilated fundus examination was performed by a retina specialist.

RESULTS

Thirty-seven eyes (20 patients, 8 females) were finally included in the analysis. Mean age of the patients enrolled was 58.0 ± 11.6 years [range 31-80 years]. The level of DR identified on montage widefield images agreed exactly with indirect ophthalmoscopy in 97.3% (36) of eyes and was within 1 step in 100% (37) of eyes. Cohen's kappa coefficient (κ) was 0.96, this suggesting an almost perfect agreement between the two modalities in DR screening. Nonmydriatic montage widefield imaging acquisition time was significantly shorter than that of dilated clinical examination (p = 0.010).

CONCLUSION

Nonmydriatic montage widefield images were compared favorably with dilated fundus examination in defining DR severity; however, they are acquired more rapidly.

Comparison Between Ultra-Widefield Pseudocolor Imaging and Indirect Ophthalmoscopy in the Detection of Peripheral Retinal Lesions

BACKGROUND AND OBJECTIVE

To systematically compare the intermodality and inter-rater agreement for indirect ophthalmoscopy and ultra-widefield (UWF) imaging in detecting peripheral retinal lesions predisposing to retinal rhegmatogenous detachment.

PATIENTS AND METHODS

In this prospective, observational, cross-sectional study, patients with a previous diagnosis of peripheral retinal lesions were enrolled. UWF pseudocolor imaging and dilated fundus examination were obtained.

RESULTS

Thirty-seven eyes (20 patients, 12 females) were enrolled. The level of inter-rater agreement was excellent in both the ophthalmoscopy-based and UWF-based assessment. The overall agreement in the UWF-based assessment was found to be Kappa = 0.874 (P < .0001). The UWF-based evaluation was demonstrated to have a sensitivity of 89.2% in detecting peripheral retinal lesions. In the sectorial analysis, the UWF-based reading had a lower sensitivity in the inferior sector.

CONCLUSION

The identification of peripheral retinal lesions with UWF imaging allowed for an accurate and reproducible assessment. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:544-549.].

Choroidal luminal and stromal areas and choriocapillaris perfusion are characterised by a non-linear quadratic relation in healthy eyes

PURPOSE

To assess the associations among different optical coherence tomography (OCT) structural and angiography quantitative metrics used to characterise the choroid in healthy subjects.

METHODS

In this cross-sectional study, macular structural OCT and OCT angiography (OCTA) images were acquired from healthy subjects. The main outcome measures were: (i) choriocapillaris (CC) flow deficits percentage (FD%), (ii) choroidal luminal (LA) and stromal (SA) areas and (iii) choroidal vascularity index (CVI), which was calculated as the LA divided by the total choroidal area. These measurements were generated using previously published algorithms and were separately computed in the foveal and extrafoveal regions.

RESULTS

Eighty-five eyes from 85 subjects (44 males, 41 females) were included in the analysis. Mean±SD age was 47.9±22.4 years (range: 19.0 to 85.0 years). Linear regression analysis displayed no significant associations between CC FD% and other parameters (LA, SA and CVI). Importantly, non-linear regression analysis showed that the relations of LA and SA to CC FD% were all best fitted by a quadratic function. Compared with the linear models, the use of the quadratic function allowed a relative increase in the R² coefficients. No significant non-linear associations were found between CC FD% and CVI.

CONCLUSION

Based on our models, changes in the luminal and stromal areas in the choroid lead to an initial increase in CC perfusion. Subsequently, further increases in LA and SA amounts are accompanied by a progressive increment in CC FD%.

One-year follow-up of ischemic index changes after intravitreal dexamethasone implant for diabetic macular edema: an ultra-widefield fluorescein angiography study

AIM

To investigate late changes in peripheral ischemia in patients affected by diabetic macular edema (DME) and treated with repeated dexamethasone (DEX) intravitreal implants over a 1-year period.

METHODS

In this retrospective cohort study, patients older than 18 years of age and with type 2 non-proliferative treatment-naïve diabetic retinopathy (DR) and DME at baseline were included. All patients were treated with two intravitreal DEX implants within 1 year of follow-up. A minimum of two annual ultra-widefield fluorescein angiography (UWF FA) were required to ensure that all cases had a baseline UWF FA (< 2 weeks before first treatment with dexamethasone) and a UWF FA performed at 12 months of follow-up. On baseline and 1-year UWFA images, peripheral retinal ischemia was quantified using the ischemic index (ISI).

RESULTS

Six eyes of five patients (two males, three females) met the inclusion criteria and were enrolled in this study. Best-corrected visual acuity was 0.34 ± 0.22 LogMAR at baseline and improved to 0.21 ± 0.14 logMAR at the 1-year follow-up visit (P = 0.050). Mean ± SD central macular thickness was 467.6 ± 63.0 μm at baseline and 272.0 ± 14.7 μm at the 1-year follow-up visit (P = 0.043). Mean ± SD ISI was 26.7 ± 14.1% at baseline and reduced to 12.2 ± 5.0% at the 1-year follow-up visit (P = 0.012).

CONCLUSIONS

Improvement in retinal perfusion is still maintained 1 year after starting treatment with DEX implants. This improvement in retinal perfusion might be related to DEX implant-related positive effects on leukostasis.

OCT-A characterisation of recurrent type 3 macular neovascularisation

Purpose

To investigate optical coherence tomography angiography (OCT-A) findings in recurrent type 3 macular neovascularisation (MNV).

Methods

In this retrospective cohort study, consecutive patients with type 3 MNV secondary to age-related macular degeneration underwent OCT-A at three different time points: baseline, after anti-vascular endothelial growth factor treatment with complete resolution of the exudative signs (ie, non-exudative stage) and at the recurrence of exudation (ie, recurrence stage). Demographics and clinical findings were analysed, including OCT-A features of type 3 MNV recurrence.

Results

Twelve eyes (12 patients, mean age 78±7 years) were included. Using OCT-A, at baseline all type 3 MNVs showed the presence of detectable flow downgrowing from the deep vascular complex (DVC) to the retinal pigment epithelium (RPE)/sub-RPE space. 6/12 eyes (50%) showed anomalous flow under the RPE, while the other 6 eyes showed flow reaching the RPE without anomalous flow in the sub-RPE space. At the non-exudative stage (after treatment), BCVA and CMT significantly improved (p=0.004 and p=0.036), and flow inside the retinal lesions reduced; interestingly the connection to the RPE/sub-RPE space regressed. At the time of recurrence, all type 3 MNVs showed the presence of intra/sub-retinal exudation with restoration of the flow deepening from the DVC to the RPE/sub-RPE space.

Conclusions

Detectable flow deepening from the DVC to the RPE/sub-RPE space using OCT-A is mandatory to have a new exudation secondary to recurrent type 3 MNV. Early detection of type 3 MNV recurrence by OCT-A characterisation may prompt retreatment and potentially prevent progression to late stages of the disease.

Choriocapillaris flow impairment could predict the enlargement of geographic atrophy lesion

AIM

To analyse the choriocapillaris (CC) flow status in the area that subsequently showed geographic atrophy (GA) expansion secondary to age-related macular degeneration (AMD) during 1-year follow-up, matching optical coherence tomography angiography (OCT-A) and fundus autofluorescence (FAF).

METHODS

In this prospective longitudinal observational study, 30 eyes of 20 consecutive patients with GA secondary to AMD (mean age 75.5±7.4 years) were included. All patients underwent OCT-A and FAF at baseline and 1-year follow-up. Main outcome measures included analysis of perfusion density (PD) in the 'area surrounding GA margin' (between the GA border and 500 µm distance) in comparison with the 'control area' (area outside the 500 µm line), and of the 'expansion area' (area that subsequently developed GA expansion during 1-year follow-up).

RESULTS

During the 1-year follow-up, visual acuity significantly decreased from 0.34±0.38 Logarithm of the Minimum Angle of Resolution (LogMAR) to 0.39±0.40 LogMAR (p<0.001), and mean GA area increased from 6.82±5.47 mm² to 8.76±6.28 mm² (p<0.001). CC PD of the area surrounding the GA margin revealed a significant flow impairment compared with control area (PD 0.679±0.076 and 0.734±0.057, respectively (p<0.001)). Furthermore, the PD of the expansion area showed a greater CC flow impairment in comparison to the remaining area surrounding GA margin (p<0.001).

CONCLUSIONS

We reported a greater CC impairment in the area that subsequently developed GA expansion, suggesting that the CC flow impairment could predict the enlargement of GA lesion. The CC impairment could be considered as a new a risk factor for GA progression and a biomarker to be measured to determine efficacy of new interventions aiming to slow progression of GA.

Multimodal Chorioretinal Imaging in Erdheim-Chester Disease

Purpose

To analyze the subclinical intraocular involvement using multimodal imaging approach in patients affected by Erdheim-Chester disease (ECD) without ocular symptoms.

Patients and Methods

In this prospective cross-sectional study, 18 eyes of 9 consecutive patients with ECD were enrolled. Each patient underwent comprehensive ocular examination and extensive multimodal chorioretinal imaging.

Results

None of the patients presented any evidence of chorioretinal localization of disease using multimodal imaging. One patient exhibited a choroidal nevus complicated by active polypoidal choroidal neovascularization. Subretinal hyperreflective material was seen in three eyes, mainly resembling acquired vitelliform lesion. One patient had an isolated intraretinal hemorrhage. Most patients exhibited peripheral vascular abnormalities (ie, microaneurysms, peripheral vascular leakage). Fundus autofluorescence showed faint hyperautofluorescence in eleven eyes.

Conclusion

Intraocular involvement is an extremely rare event of an extremely rare disease. In patients affected by ECD without ocular symptoms, advance multimodal imaging examinations did not show signs of subclinical chorioretinal involvement related to the disease.

OCTA characterisation of microvascular retinal alterations in patients with central serous chorioretinopathy

PURPOSE

This study aimed to describe the characteristics of microvascular retinal alterations in eyes with chronic central serous chorioretinopathy (CSC) employing optical coherence tomography angiography (OCTA) analysis.

METHODS

We collected data from 472 eyes with chronic CSC from 336 patients who had OCTA obtained. Each OCTA image was graded by two readers to assess the presence of microvascular retinal alterations, including regions of vascular rarefaction/retinal hypoperfusion, enlargement of the foveal avascular zone (FAZ) and presence of telangiectasias or microaneurysms. Volume spectral domain optical coherence tomography (SD-OCT) scans were obtained through the macula and the OCT was correlated with the OCTA findings in eyes with retinal vascular alterations.

RESULTS

OCTA displayed microvascular retinal alterations in 18 out of 474 eyes (3.6%) from 14 patients (13 male and 1 female; mean±SD age was 54.7±11.1 years). One eye displayed the presence of retinal telangiectasias, while 17 out of 18 eyes were graded as having areas of retinal vascular rarefactions, and 3 out of 17 eyes were also characterised by an enlargement of the FAZ. The parafoveal region was the location most involved by retinal vascular changes (66,7%), followed by foveal (22,2%) and perifoveal (11.1%) regions, respectively.

CONCLUSION

Although CSC is known to represent a choroidal disorder, retinal vascular alterations may be present in these eyes and OCTA may represent a useful tool to identify and describe them.

Morphofunctional analysis of the retina in patients with type 1 diabetes without complications after 30 years of disease

There is a lack of studies evaluating the sub-clinical retinal changes in patients with long-term type 1 diabetes mellitus (T1DM) and without history of systemic/ocular complications. The aim of this cross-sectional study was to investigate sub-clinical structural and/or vascular retinal changes in patients with long-term (≥30 years) T1DM and without systemic/ocular complications ("happy few" patients) using structural optical coherence tomography (OCT), OCT-angiography and microperimetry. Twelve eyes of 12 consecutive T1DM patients (mean age 52 ± 12 years, mean duration of disease 35 ± 3 years, mean HbA1c level 7.3 ± 2.8%), without micro/macrovascular complications associated with long-standing T1DM, and twelve healthy subjects were consecutively included. No statistically significant differences were disclosed comparing patients and controls for age, sex, best-corrected visual acuity, central macular thickness, and choroidal thickness. Using OCT-angiography, we did not find any significant difference in foveal avascular zone area, perfusion density, vessel length density, and tortuosity. Moreover, no significant differences were disclosed in retinal nerve fiber layer and ganglion cell complex thickness using structural OCT. No differences were disclosed in retinal sensitivity by microperimetry. New diagnostic tools are able to confirm the presence of a particular population of patients with type 1 diabetes who have been completely spared from diabetic retinal complications. The finding of these "happy few" patients could help us to better understand and target future treatments for diabetes.

Prevalence and Phenotypes of Age-Related Macular Degeneration in Eyes With High Myopia

Purpose

To analyze the frequency and phenotypic variation of AMD in subjects with high myopia (HM), and to describe the clinical course and response to treatment of neovascularization (NV).

Methods

Patients with HM were identified at five retina tertiary referral centers. Inclusion criteria were myopic patients aged 55 years or more with axial lengths equal or greater than 25.5 mm.

Results

A total of 874 eyes from 442 HM subjects older than 55 years were identified and 104 eyes of 54 patients (72 ± 11 years) were included in the study and followed up for 23.5 ± 19.5 months. The estimated AMD frequency in HM subjects over 55 years was 11.9% (95% confidence interval; 9.8%-14.0%). A total of 34 of 104 eyes were diagnosed with drusen, 22 with reticular pseudodrusen (RPD), 28 with both drusen and RPD, and 20 with geographic atrophy. Neovascularization was detected in 52 eyes (50%), and type 1 was the most frequent form (39 eyes, 75%). Overall, NV was treated with 4.6 ± 2.6 anti-VEGF injections. Eyes with treatment-naïve NV at baseline (n = 34) required 3.8 ± 1.5 anti-VEGF injections during the first year of treatment. This exceeded the injection number in the purely myopic population (1.8 to 3.6 injections for the first year).

Conclusions

This study provides evidence to suggest that older patients with HM are at a significant risk of the dry and neovascular forms of AMD. NV in eyes with HM and AMD required more injections in the first year compared to NV in HM eyes without AMD.

Multimodal Imaging Assessment of Vascular and Neurodegenerative Retinal Alterations in Type 1 Diabetic Patients without Fundoscopic Signs of Diabetic Retinopathy

The aim of this cross-sectional case-control study is to investigate the possible presence of vascular/neurodegenerative alterations in the retina of type 1 diabetes mellitus (T1DM) patients without diabetic retinopathy (DR). Thirty-four eyes of 34 consecutive T1DM without DR (mean age 21 ± 2 years) were included. Another cohort of 27 eyes (27 healthy control subjects matched with age and sex) was also recruited. All patients underwent multimodal imaging evaluation using structural optical coherence tomography (OCT), OCT-angiography (OCT-A), dynamic vessel analyzer (DVA) and microperimetry. No significant differences were disclosed comparing diabetics and controls for visual acuity, central macular thickness, and subfoveal choroidal thickness. On retinal nerve fiber layer and ganglion cell complex thickness, no significant differences were disclosed comparing each 3-mm-diameter macular and peripapillary subfield between two groups. Using OCT-A, deep capillary plexus perfusion density (PD) of diabetics was significantly lower compared to control group, whereas PD of other retinal/choriocapillaris plexuses and foveal avascular zone area did not show any significant difference. Using DVA, diabetic eyes revealed a significantly decreased vessel response to flicker light in comparison to controls. No differences were disclosed using microperimetry analysis. Taken together, these results suggest that vascular alterations could be the first detectable retinal change in the development of DR.

Optical Coherence Tomography Parameters as Predictors of Treatment Response to Eplerenone in Central Serous Chorioretinopathy

Purpose: To present data on clinical response to eplerenone over a 1-year period in patients with central serous chorioretinopathy (CSC), and to evaluate optical coherence tomography (OCT) variables as predictors of treatment response at 3- and 12-month follow-up visits. Methods: Patients with acute or chronic CSC treated with eplerenone were retrospectively included. Clinical and imaging characteristics were recorded at baseline and at the 3-month and 12-month follow-up visits. Changes from baseline in quantitative measurements were calculated at each follow-up. Logistic regression analysis was computed to correlate clinical and OCT parameters at baseline with response to treatment at 3 and 12 months of follow-up. Results: A total of 50 eyes of 50 patients were included in the study. Mean ± SD best corrected visual acuity (BCVA) was 0.20 ± 0.14 Logarithm of the Minimum Angle of Resolution (LogMAR) at baseline and significantly improved at both the 3-month (0.12 ± 0.13 LogMAR, p < 0.0001) and 12-month (0.10 ± 0.12 LogMAR, p < 0.0001) follow-up visits. At the 3-month follow-up visit, 25 out of 50 eyes (50.0%) demonstrated macular complete subretinal fluid (SRF) resolution, while 13 eyes (26.0%) showed macular partial SRF resolution, and 12 eyes (24%) had neither partial nor complete macular SRF resolution. Among those patients with macular partial or complete SRF resolution at 3 months and thus not shifted to photodynamic therapy, 36 out of 38 cases had macular complete SRF resolution at the 12-month follow-up visit. There was a significant change from baseline at both follow-up visits in all anatomical OCT parameters (except for reduction in choroidal thickness that did not reach the statistical significance at the 12-month follow-up visit). Several OCT parameters at baseline were independently significant predictors for macular subretinal fluid complete resolution at 3 months, including (i) a thicker subfoveal choroidal thickness; (ii) a smaller subretinal fluid maximum diameter; (iii) a lower number of serous pigment epithelium detachments; and (iv) a lower number of intraretinal hyperreflective foci. Conclusion: Treatment with eplerenone in CSC patients is confirmed to be beneficial for both anatomical and functional outcomes. We identified attractive OCT metrics that could potentially be used as a tool to select patients who might mainly benefit from this treatment.

Early response to the treatment of choroidal neovascularization complicating central serous chorioretinopathy: a OCT-angiography study

PURPOSE

To analyze the quantitative and qualitative early changes of choroidal neovascularization (CNV) associated with chronic central serous chorioretinopathy (CSC) after treatment using optical coherence tomography-angiography (OCT-A).

METHODS

Charts of consecutive patients with diagnosis of chronic CSC complicated by CNV were retrospectively reviewed. Included patients were divided in photodynamic therapy (PDT) or aflibercept group on the basis of the treatment received (half-fluence PDT or aflibercept 2.0 mg/0.05 ml intravitreal injection). Main outcome measures included the changes between baseline and 1-month follow-up in CNV vessel density (VD) and area on OCT-A images after thresholding and binarization.

RESULTS

A total of 30 eyes of 26 Caucasian patients were included: 17 eyes of 15 patients in PDT group (mean age 53 ± 11 years) and 13 eyes of 11 patients in aflibercept group (mean age 58 ± 8 years [p = 0.196]). In both PDT and aflibercept groups, best-corrected visual acuity improved at 1 month, and central macular thickness and subretinal fluid significantly decreased. VD did not change after the treatment in both groups (p = 0.502 and p = 0.086) although CNV area decreased significantly (from 0.586 ± 0.449 mm² to 0.553 ± 0.453 mm² [0.041]) in the PDT group, and nonsignificantly (from 0.767 ± 0.466 mm² to 0.733 ± 0.472 mm² [p = 0.095]) in the aflibercept group. The same results were confirmed in the subanalysis of the 18 treatment-naïve eyes.

CONCLUSIONS

We demonstrated that, despite all patients showed a favorable clinical response, VD of CNVs complicating chronic CSC did not change after treatment. These findings support the idea that arteriogenesis is the main driving force of CNV in pachychoroid-related macular disorders.

Anatomical and functional changes in neovascular AMD in remission: comparison of fibrocellular and fibrovascular phenotypes

PURPOSE

To investigate the anatomical changes and the macular function in neovascular age-related macular degeneration (AMD) eyes, according to the recognition of either fibrocellular or fibrovascular phenotype.

METHODS

We enrolled eyes with previously treated neovascular AMD in remission (no subretinal haemorrhage, sign of fluid in or under the retina and no treatment for at least 6 months). Subjects underwent multimodal imaging assessment and were tested for macular sensitivity using microperimetry. The study cohort was divided according to the presence of fibrosis on multicolour (MC) images, yielding two distinct phenotypic subgroups: (1) fibrocellular group and (2) fibrovascular group.

RESULTS

Nineteen eyes were classified as fibrocellular on MC images, while 22 eyes as fibrovascular. Mean±SD age was 73.9±11.0 years in the fibrocellular group and 75.9±7.1 years in the fibrovascular group (p=0.221). Best-corrected visual acuity was 0.7±0.5 logarithm of the minimum angle of resolution (LogMAR) in the fibrocellular group and 0.3±0.2 LogMAR in the fibrovascular group (p=0.003). On the optical coherence tomography and fundus autofluorescence evaluation, 17/19 eyes with the fibrocellular phenotype and 8/22 eyes with the fibrovascular phenotype displayed the presence of retinal pigment epithelium (RPE) atrophy (p=0.001). The perfusion density within the neovascular lesion was 28.9%±9.9% in the fibrocellular group and 44.2%±5.9 % in the fibrovascular group (p<0.0001).

CONCLUSION

Neovascular AMD eyes in remission and with evidence of fibrocellular scar are characterised by RPE atrophy and reduced perfusion, which are associated with a higher degree of functional impairment. These findings suggest that maturation of vessels in fibrosis might be a better target in neovascular AMD treatments rather than their abolishment.

Choroidal Caverns: A Previously Unreported Optical Coherence Tomography Finding in Best Vitelliform Dystrophy

Best vitelliform macular dystrophy (VMD) is an autosomal dominant inherited dystrophy, most frequently caused by mutations in the BEST1 gene. The authors describe "choroidal caverns," a previously unreported optical coherence tomography finding in the choriocapillary and choroid of Best VMD. Histopathologic examination in eyes with Best VDM shows extensive deposition of lipofuscin in the retinal pigment epithelium (RPE) throughout the retina and accumulation of fibrillar material under the RPE and in the choroid. This supports the hypothesis that choroidal caverns could be a sign of the degenerative process involving the choroid in eyes with Best VMD. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:284-287.].