Enhanced depth imaging optical coherence tomography of retinal pigment epithelial detachment in age-related macular degeneration

Macular neovascularization

Neovascularization of the macula, a common complication of many chorioretinal diseases such as neovascular age-related macular degeneration, polypoidal choroidal vasculopathy, and pathologic myopia results from increased synthesis of vascular endothelial growth factor (VEGF) by the retinal pigment epithelium and/or Müller cells because of localized ischemia and inflammation. The Consensus on Neovascular AMD Nomenclature (CONAN) study group acknowledged that these vessels may originate from either the choriocapillaris or the retinal microvasculature, prompting them to propose the term 'macular neovascularization' (MNV) to include intraretinal, subretinal, and sub-pigment epithelial neovascularization localized to the macula. MNV frequently appears as a grey-green macular lesion with overlying intraretinal thickening and/or subretinal exudation, causing metamorphopsia, reduced central vision, relative central scotoma, decreased reading speed, and problems with color recognition. Multimodal imaging with optical coherence tomography (OCT), OCT angiography, dye-based angiographies, fundus autofluorescence, and multiwavelength photography help establish the diagnosis and aid in selecting an appropriate treatment. The standard of care for MNV is usually intravitreal anti-VEGF injections, though thermal laser photocoagulation, verteporfin photodynamic therapy, and vitreoretinal surgery are occasionally used. This current review discusses the etiology and clinical features of MNV, the role of multimodal imaging in establishing the diagnosis, and the available therapeutic options.

A real-world data analysis of ocular adverse events linked to anti-VEGF drugs: a WHO-VigiAccess study

Introduction

Vascular endothelial growth factor (VEGF) is key to wet age-related macular degeneration (wAMD). Anti-VEGF drugs are the main treatment in clinics. This study assessed ocular adverse events (AE) from anti-VEGF drugs in VigiAccess, WHO's database, and compared adverse drug reaction (ADR) profiles of four drugs to aid personalized treatment choices for optimal benefit and safety.

Methods

The design was a descriptive retrospective study. We observed four anti-VEGF drugs commonly used in the clinical treatment of wAMD, and their ADR reports came from WHO-VigiAccess. The collected data included the age group, gender, and regional data, as well as the data of disease systems and symptoms caused by ADR recorded in the annual ADR reports and reports received by the WHO. We observed the overall characteristics of the ADR reports of these drugs, then explored the distribution of 27 SOCs of these drugs. Subsequently, we compared the most common ocular ADRs of the drugs. Finally, we compared the commonalities and differences of ocular ADRs related to the drugs.

Results

Overall, 57,779 AE associated with the four anti-VEGF drugs were reported. The results showed that the number of females experiencing ADRs (67.83%) was significantly higher than males (32.17%), the age group with the highest reported incidence was over 75 years old. More than half of the ADR reports came from the Americas (50.86%). The five most common types of AE were: eye disorders (43.56%), general disorders and administration site conditions (34.47%), injury poisoning and procedural complications (13.36%), infections and infestations (11.61%), nervous system disorders (9.99%). Compared with the other three inhibitors, brolucizumab had a significantly higher rate of ocular ADR reports. The most common ocular ADRs of these four anti-VEGF drugs were mostly related to visual impairment, vision blurred, and blindness. However, there is still a disparity of ADRs between different drugs.

Conclusion

The presence of ocular AEs when using anti-VEGF drugs to treat wAMD in clinical practice should attract clinical attention. Clinicians should use these expensive drugs more rationally based on the characteristics of ADRs and develop personalized treatment plans for patients.

Long-term Follow-Up and Regeneration of Retinal Pigment Epithelium (RPE) after Tears of the Epithelium in Exudative Age-Related Macular Degeneration (AMD)

BACKGROUND

The goals of this study are to evaluate potential long-term visual deterioration associated with retinal pigment epithelial (RPE) tears in patients with neovascular age-related macular degeneration (nAMD) and to find treatment-related and morphological factors that might influence the outcomes.

PATIENTS AND METHODS

This retrospective study enrolled 21 eyes of 21 patients from the database of Vista Eye Clinic Binningen, Switzerland, diagnosed with RPE tears, as confirmed by spectral domain optical coherence tomography (SD-OCT), with a minimum follow-up period of 12 months. Treatment history before and after RPE rupture with anti-VEGF therapy, visual acuity, and imaging (SD-OCT) were analyzed and statistically evaluated for possible correlations.

RESULTS

Mean patient age was 80.5 ± 6.2 years. The mean length of total follow-up was 39.7 ± 13.9 months. The mean pigment epithelial detachment (PED) height increased by 363.8 ± 355.5 µm from the first consultation to 562.8 ± 251.5 µm at the last consultation prior to rupture. Therefore, a higher risk of RPE rupture is implied as a result of an increase in PED height (p = 0.004, n = 14). The mean visual acuity before rupture was 66.2 ± 16.0 letters. Mean visual acuity deteriorated to 60.8 ± 18.6 letters at the first consultation after rupture (p = 0.052, n = 21). A statistically nonsignificant decrease in vision was noted in the follow-up period. After 2 years, the mean BCVA decreased by 10.5 ± 23.7 ETDRS letters (p = 0.23, n = 19). PED characteristics before rupture and amount of anti-VEGF injections after rupture did not affect the visual outcome. None of the 21 patients included in our study showed a visual improvement in the long-term follow-up. RPE atrophy increased significantly from 3.35 ± 2.94 mm2 (baseline) to 6.81 ± 6.25 mm2 over the course of 2 years (p = 0.000 013, n = 20).

CONCLUSIONS

The overall mean vision decrease after rupture was without statistical significance. There was no significant change in BCVA at the 2-year follow-up, independent of the amount of anti-VEGF injections provided. In this study, there was a significant increase in RPE defect over a follow-up of 2 years, implying progression of contraction of RPE and/or macular atrophy.

Optical Coherence Tomographic Optic Nerve Head Morphology in Myopia III: The Exposed Neural Canal Region in Healthy Eyes-Implications for High Myopia

PURPOSE

To determine the prevalence and magnitude of optical coherence tomography (OCT) exposed neural canal (ENC), externally oblique choroidal border tissue (EOCBT), and exposed scleral flange (ESF) regions in 362 non-highly myopic (spherical equivalent -6.00 to 5.75 diopters) eyes of 362 healthy subjects.

DESIGN

Cross-sectional study.

METHODS

After OCT optic nerve head (ONH) imaging, Bruch membrane opening (BMO), the anterior scleral canal opening (ASCO), and the scleral flange opening (SFO) were manually segmented. BMO, ASCO, and SFO points were projected to the BMO reference plane. The direction and magnitude of BMO/ASCO offset as well as the magnitude of ENC, EOCBT, and ESF was calculated within 30° sectors relative to the foveal-BMO axis. Hi-ESF eyes demonstrated an ESF ≥100 µm in at least 1 sector. Sectoral peri-neural canal choroidal thickness (pNC-CT) was measured and correlations between the magnitude of sectoral ESF and proportional pNC-CT were assessed.

RESULTS

Seventy-three Hi-ESF (20.2%) and 289 non-Hi-ESF eyes (79.8%) were identified. BMO/ASCO offset as well as ENC, EOCBT, and ESF prevalence and magnitude were greatest inferior temporally where the pNC-CT was thinnest. Among Hi-ESF eyes, the magnitude of each ENC region correlated with the BMO/ASCO offset magnitude, and the sectors with the longest ESF correlated with the sectors with proportionally thinnest pNC-CT.

CONCLUSIONS

ONH BMO/ASCO offset, either as a cause or result of ONH neural canal remodeling, corresponds with the sectoral location of maximum ESF and minimum pNC-CT in non-highly myopic eyes. Longitudinal studies to characterize the development and clinical implications of ENC Hi-ESF regions in non-highly myopic and highly myopic eyes are indicated.

Choroidal thickness and effect of sex and age in Africans

Purpose

The purpose of the study is to evaluate choroidal thickness (CT) and the effect of age and gender in healthy Africans using enhanced depth imaging spectral-domain optical coherence tomography.

Materials and Methods

In 172 eyes of 88 volunteers, the CT in the central subfoveal (CSF) area and at 2.5 mm superior, inferior, nasal, and temporal quadrants was measured. Four eyes were excluded due to poor image quality and image decentration. Simple linear regression was used to measure the effect of age on CT, and statistical analysis was done using IBM SPSS Statistics version 22.

Results

The were 88 male and 84 female eyes, aged 30-80 years. The mean CT was CSF 265.44 ± 6.2 μm; inferior 256.19 ± 70.6 μm; superior 249.92 ± 76.2 μm; temporal 235.51 ± 70.3 μm; and nasal 199.53 ± 69.8 μm. The choroid was thickest in the CSF > Inferior > Superior > Temporal, and the nasal quadrant was thinnest in all age groups. There was a considerable decrease in the CSF with increasing age (P < 0.001). CT in males and females was similar since the difference in mean CSF CT between the genders was 2.085 μm (P = 0.858). Menopausal females had thinner CSF CT compared to premenopausal females (P < 0.001), but this was due to the aging effect.

Conclusion

CT decreases significantly with increasing age but shows no gender difference in Africans. A comparison of CT studies from other ethnic nationalities shows some similarity with CT in Africans, suggesting that CT findings from other ethnic groups can be extrapolated to Africans.

Short time effect of sodium fluorescein on chorodial vascularity index

PURPOSE

This study aimed to investigate the effect of sodium fluorescein on the choroidal vascularity index (CVI).

MATERIALS AND METHODS

In this cross-sectional study, a total of 27 eyes of 27 mild nonproliferative diabetic retinopathy patients (without maculopathy and any systemic disease) who performed fluorescein angiography (FA) procedure were included. Choroidal parameters such as choroidal thickness (CT), total choroidal area (TCA), luminal area (LA), stromal area (SA), LA/SA, and CVI were examined with the optical coherence tomography and binarization technique at baseline and 5th, 15th, and 30th minutes after FA. The values of the parameters before and after the procedure were compared.

RESULTS

At baseline, the mean values of the TCA, LA, SA, LA/SA, and CVI were 0.44 ± 0.14mm2, 0.29 ± 0.09 mm2, 0.15 ± 0.05 mm2, 1.87 ± 0.19. Five minutes later to FA, the mean values of the TCA, LA, SA, LA/SA, and CVI were 0.43 ± 0.13 mm2, 0.28 ± 0.08 mm2, 0.15 ± 0.05 mm2, 1.82 ± 0.20, and 0.64 ± 0.03, respectively. There was a significant decrease in LA and CVI values 5 minutes after FA (p:0.002 and p:0.021, respectively). On the other hand, the mean, nasal, subfoveal, and temporal CT were 279.22 ± 93.40 μm, 289.78 ± 91.17 μm, 267.44 ± 95.71 μm before FA and 270.33 ± 90.34 μm, 279.67 ± 90.01 μm, 261.82 ± 95.82 μm 5 minutes after FA (p = 0.960, p = 0.952, and p = 0.991, respectively). Although there was a reduction in the value of CT, there was not a statistically significant difference between before and after FA.

CONCLUSIONS

This study shows that there was a significant decrease in LA and CVI values 5 minutes after FA in patients with mild nonproliferative diabetic retinopathy.

The Choroidal Vascularity Index Versus Optical Coherence Tomography Angiography in the Evaluation of the Choroid with a Focus on Age-Related Macular Degeneration

The choroid is the most vascularized structure of the eye and it is fundamental for the trophism of the outer retina. Its proper functioning and homeostasis represent key points in maintaining normal retinal physiology. Choroidal alterations may be implicated in the development and progression of numerous pathologies; therefore, in-depth studies using imaging techniques can be of crucial relevance to understanding the pathophysiology of retinal-choroidal diseases. The advent of spectral-domain optical coherence tomography (SDOCT) has enabled the non-invasive study of the choroid in vivo and the most recent development, optical coherence tomography angiography (OCTA), allows for the high-resolution visualization of the choriocapillaris and the choroid in regard to vascularization. The choroidal vascularity index (CVI) is a new parameter calculated on SDOCT scans and is defined as the ratio of the luminal area to the total choroidal area. In this review, a study of the choroid using OCTA and CVI will be evaluated in depth and the pros and cons of these two methods will be analyzed, with a particular focus on age-related macular degeneration.

Pigment epithelial detachment composition indices (PEDCI) in neovascular age-related macular degeneration

We provide an automated analysis of the pigment epithelial detachments (PEDs) in neovascular age-related macular degeneration (nAMD) and estimate areas of serous, neovascular, and fibrous tissues within PEDs. A retrospective analysis of high-definition spectral-domain OCT B-scans from 43 eyes of 37 patients with nAMD with presence of fibrovascular PED was done. PEDs were manually segmented and then filtered using 2D kernels to classify pixels within the PED as serous, neovascular, or fibrous. A set of PED composition indices were calculated on a per-image basis using relative PED area of serous (PEDCI-S), neovascular (PEDCI-N), and fibrous (PEDCI-F) tissue. Accuracy of segmentation and classification within the PED were graded in masked fashion. Mean overall intra-observer repeatability and inter-observer reproducibility were 0.86 ± 0.07 and 0.86 ± 0.03 respectively using intraclass correlations. The mean graded scores were 96.99 ± 8.18, 92.12 ± 7.97, 91.48 ± 8.93, and 92.29 ± 8.97 for segmentation, serous, neovascular, and fibrous respectively. Mean (range) PEDCI-S, PEDCI-N, and PEDCI-F were 0.253 (0-0.952), 0.554 (0-1), and 0.193 (0-0.693). A kernel-based image processing approach demonstrates potential for approximating PED composition. Evaluating follow up changes during nAMD treatment with respect to PEDCI would be useful for further clinical applications.

Dexamethasone implant prior to anti-VEGF therapy in pigment epithelium detachments with high-risk rupture characteristics secondary to neovascular age-related macular degeneration

OBJECTIVE

Evaluate the incidence of pigment epithelial tear when intravitreal delayed-release dexamethasone implant is administered (off-label use) prior to antiangiogenic treatment in pigment epithelium detachments (PED) secondary to neovascular age-related macular degeneration (nAMD) with high-risk rupture characteristics and investigate if it causes a decrease in the PED size.

METHODS

Patients with nAMD, PED height >500 microns and Ozurdex implant prior to the antiangiogenic therapy were included. The presence of pigment epithelium rupture in optical coherence tomography scans, best-corrected visual acuity (BCVA) and PED measurements (maximum height and diameter) were registered.

RESULTS

The study included 14 eyes of 14 patients: mean age 77 ± 7 years, 11 (79%) females. 25 ± 13 days after the Ozurdex, patients started with at least 3 anti-VEGF monthly injections. BCVA improved from 64 ± 14-69 ± 11 letters after anti-VEGF therapy (p > 0.05). Mean baseline PED height was 817 ± 269 µm, being 639 ± 268 µm after Ozurdex and 370 ± 260 µm after anti-VEGF injections (p = 0.035 and p = 0.009). One retinal pigment epithelium tear occurred (7%). No other adverse effects were reported.

CONCLUSIONS

Dexamethasone implant prior to anti-VEGF therapy may represent a promising therapeutic modality for large PED in nAMD, reducing PED dimensions and the risk of pigment epithelium tears prior to anti VEGF therapy.

Ocular adverse events associated with anti-VEGF therapy: A pharmacovigilance study of the FDA adverse event reporting system (FAERS)

Background: The purpose of this study is to identify and characterize ocular adverse events (AEs) that are significantly associated with anti-VEGF drugs for treatment of neovascular age-related macular degeneration and compare the differences between each drug, and provide clinical reference. Methods: Ocular AEs submitted to the US Food and Drug Administration were analyzed to map the safety profile of anti-VEGF drugs. The Pharmacovigilance tools used for the quantitative detection of signals were reporting odds ratio and bayesian confidence propagation neural network. Results: A total of 10,608,503 AE reports were retrieved from FAERS, with 20,836 for ranibizumab, 19,107 for aflibercept, and 2,442 for brolucizumab between the reporting period of Q1, 2004 and Q3, 2021. We found and analyzed the different AEs with the strongest signal in each drug-ranibizumab-macular ischaemia (ROR = 205.27, IC-2SD = 3.70), retinal pigment epithelial tear (ROR = 836.54, IC-2SD = 7.19); aflibercept-intraocular pressure increased (ROR = 31.09, IC-2SD = 4.61), endophthalmitis (ROR = 178.27, IC-2SD = 6.70); brolucizumab-retinal vasculitis (ROR = 2930.41, IC-2SD = 7.47) and/or retinal artery occlusion (ROR = 391.11, IC-2SD = 6.10), dry eye (ROR = 12.48, IC-2SD = 2.88). Conclusion: The presence of AEs should bring clinical attention. The use of anti-VEGF drugs should be based on the patient's underlying or present medical condition to reduce any adverse event associated with the treatment.

Choroidal Vasculature Changes in Age-Related Macular Degeneration: From a Molecular to a Clinical Perspective

The contribution of choroidal vasculature to the pathogenesis of age-related macular degeneration (AMD) has been long debated. The present narrative review aims to discuss the primary molecular and choroidal structural changes occurring with aging and AMD with a brief overview of the principal multimodal imaging modalities and techniques that enable the optimal in vivo visualization of choroidal modifications. The molecular aspects that target the choroid in AMD mainly involve human leukocyte antigen (HLA) expression, complement dysregulation, leukocyte interaction at Bruch’s membrane, and mast cell infiltration of the choroid. A mechanistic link between high-risk genetic loci for AMD and mast cell recruitment has also been recently demonstrated. Recent advances in multimodal imaging allow more detailed visualization of choroidal structure, identifying alterations that may expand our comprehension of aging and AMD development.

Volumetric subfield analysis of cynomolgus monkey’s choroid derived from hybrid machine learning optical coherence tomography segmentation

This study aimed to provide volumetric choroidal readings regarding sex, origin, and eye side from healthy cynomolgus monkey eyes as a reference database using optical coherence tomography (OCT) imaging. A machine learning (ML) algorithm was used to extract the choroid from the volumetric OCT data. Classical computer vision methods were then applied to automatically identify the deepest location in the foveolar depression. The choroidal thickness was determined from this reference point. A total of 374 eyes of 203 cynomolgus macaques from Asian and Mauritius origin were included in the analysis. The overall subfoveolar mean choroidal volume in zone 1, in the region of the central bouquet, was 0.156 mm³ (range, 0.131–0.193 mm³). For the central choroid volume, the coefficient of variation (CV) was found of 6.3%, indicating relatively little variation. Our results show, based on analyses of variance, that monkey origin (Asian or Mauritius) does not influence choroid volumes. Sex had a significant influence on choroidal volumes in the superior-inferior axis (p ≤ 0.01), but not in the fovea centralis. A homogeneous foveolar choroidal architecture was also observed.

Blue-light fundus autofluorescence imaging of pigment epithelial detachments

BACKGROUND

Pigment epithelial detachments (PEDs) occur in association with various chorioretinal diseases. With respect to the broad clinical spectrum of PEDs we describe fundus autofluorescence (FAF) characteristics of PEDs.

METHODS

Ninety-three eyes of 66 patients (mean age 71.9 ± 11.1) with uni- or bilateral PED ( ≥ 350 µm) were included in a retrospective cross-sectional study. PEDs were secondary to age-related macular degeneration (n = 79), central serous chorioretinopathy (n = 7), polypoidal choroidal vasculopathy (n = 2), pattern dystrophy (n = 3) or idiopathic PED (n = 2). FAF images were recorded using confocal scanning laser ophthalmoscopy (488 nm excitation wavelength, detection of emission >500 nm). Diagnosis of PED was confirmed using spectral-domain optical coherence tomography. A qualitative FAF grading system was established, and grading was performed by two independent readers.

RESULTS

PEDs showed highly variable characteristics on FAF imaging. FAF within the area of PED was found to be irregular/granular (n = 59, 63.4%), increased (n = 28, 30.1%), decreased (n = 3, 3.2 %), or normal (n = 3, 3.2%). Accompanying FAF changes included condensation of macular pigment (n = 67, 72.0%), focally increased FAF at the PED apex (n = 14, 15.1%) or elsewhere (n = 52, 55.9%), focally decreased FAF (n = 23, 24.7%), a cartwheel-like pattern (n = 10, 10.8%), a doughnut sign (n = 6, 6.5%), and a halo of decreased FAF encircling the PED (completely n = 20, 21.5% or incompletely n = 20, 21.5%).

CONCLUSIONS

PEDs show a variety of abnormal patterns on FAF imaging. These changes in FAF signals may be secondary to morphological and metabolic alterations within corresponding retinal layers and do not necessarily correspond with the underlying PED subtype or a specific pathology.

Disc–fovea distance and choroidal thickness: is there a relationship?

Background:

The distance between the optic disc center and the fovea is a biometric parameter; however, it is unclear whether DFD (disc–fovea distance) affects the choroidal thickness.

Objective:

The aim of this study is to investigate the association between DFD and choroidal thickness.

Design:

This is a prospective, and cross-sectional study.

Methods:

Two hundred fifty eyes of 250 healthy participants were examined in terms of DFD, age, axial length, spherical equivalent, and choroidal thickness. Inclusion criteria included aged between 20–40 years, no posterior segment disorders, and participants with best-corrected visual acuity (10/10 according to Snellen’s chart). Participants with high hypermetropia (>4 diopter) or myopia (>6 diopter) or any systemic disease likely to affect choroidal thickness were excluded. Choroidal thickness measurements were performed at subfoveal, 1.0 mm temporal, and 1.0 mm nasal using the enhanced-depth imaging optical coherence tomography.

Results:

The mean age of all the participants was 26.21 ± 5.73 years, mean DFD was 4634.29 ± 274.70 µm, mean axial length was 23.62 ± 0.83 mm, and mean spherical equivalent was −0.61 ± 1.06 diopter. The mean subfoveal, nasal, and temporal choroidal thicknesses were 388.73 ± 90.15 µm, 351.26 ± 88.09 µm, and 366.50 ± 79.56 µm, respectively. A negative correlation was found between subfoveal, nasal, and temporal choroidal thicknesses and axial length (r = −0.157, p = 0.013; r = −0.168, p = 0.008; r = −0.174, p = 0.006, respectively). Insignificant correlation was found between choroidal thicknesses and spherical equivalent (p > 0.05). There was not a statistically significant correlation between DFD and subfoveal, nasal, and temporal choroidal thicknesses (r = −0.028, p = 0.655; r = 0.030, p = 0.641; r = −0.025, p = 0.699, respectively). In addition, there was not a statistically significant correlation between age and choroidal thickness.

Conclusion:

This study shows that DFD and spherical equivalent do not affect choroidal thickness; axial length negatively affects choroidal thickness. In addition, age does not affect choroidal thickness between 20 and 40 years.

Genotyping of Clinical Parameters in Age-Related Macular Degeneration

Background

Methods

Results

Conclusion

Modern trends in diagnostics and prediction of results of anti-vascular endothelial growth factor therapy of pigment epithelial detachment in neovascular agerelated macular degeneration using deep machine learning method (literature review)

Detachment of the pigment epithelium is the separation of the basement membrane of the retinal pigment epithelium from the inner collagen layer of Bruch’s membrane, which occurs in 80 % of cases in patients with neovascular age-related macular degeneration. The outcome of anti-VEGF therapy for pigment epithelial detachment may be adherence of the pigment epithelium, the formation of pigment epithelium tear, or preservation of the detachment. The pigment epithelium tear of 3–4th degrees can lead to a sharp decrease in visual acuity.Most retrospective studies confi rm the absence of a proven correlation between anatomical and functional outcomes in the treatment of pigment epithelial detachment in cases of maintaining the integrity of the pigment epithelium monolayer, and therefore the main attention of researchers is focused on studying the morphological features of pigment epithelial detachment during therapy with angiogenesis inhibitors. Modern technologies of spectral optical coherence tomography make it possible to evaluate detailed quantitative parameters of pigment epithelium detachment, such as height, width, maximum linear diameter, area, volume and refl ectivity within the detachment.Groups of Russian and foreign authors identify various biomarkers recorded on optical coherence tomography images. Dynamic registration of such biomarkers expands the ability of clinicians to predict morphological changes in pigment epithelial detachment during anti-VEGF therapy, as well as to optimize treatment regimens to prevent complications in the form of pigment epithelium tear leading to a decrease in visual acuity.Modern methods of deep machine learning and the use of neural networks allow achieving higher accuracy in diff erentiating the types of retinal fluids and automating the quantitative determination of fl uid under the pigment epithelium. These technologies allow achieving a high level of compliance with manual expert assessment and increasing the accuracy and speed of predicting morphological results of treatment of pigment epithelium detachments.

Intravitreal Ozurdex has no short term influence on choroidal thickness and vascularity index in eyes with diabetic macular edema: A pilot study

AIM:

To analyze choroidal parameters in eyes with diabetic macular edema (DME) treated with intravitreal Ozurdex.

PATIENTS AND METHODS:

Twenty eyes of 14 patients were included in this prospective study. Optical coherence tomography images were obtained before and 8–10 weeks after intravitreal Ozurdex injection; binarized and subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) were calculated.

RESULTS:

Mean SFCT (treatment naïve; 242.22 ± 32.87 reduced to 218.10 ± 22.10, P = 0.158 and previously treated; 330.4 ± 56.72 reduced to 328.93 ± 50.55, P = 0.833) and mean CVI (treatment naïve; 0.64 ± 0.03 changed to 0.65 ± 0.04, P = 0.583 and previously treated; 0.65 ± 0.05 reduced to 0.64 ± 0.03, P = 0.208) showed no significant change.

CONCLUSION:

Intravitreal Ozurdex showed no significant effects on SFCT and CVI in eyes with DME over short term. Larger studies with longer follow-up may allow a better understanding.

Prechoroidal cleft thickness correlates with disease activity in neovascular age-related macular degeneration

Purpose

The purpose of this study was to investigate the structural variations of the hyporeflective pocket of fluid (prechoroidal cleft) located between Bruch’s membrane and the hyperreflective material within the pigment epithelial detachment (PED) in patients with neovascular age-related macular degeneration (nAMD).

Methods

In this retrospective, observational case series study, patients diagnosed with nAMD and prechoroidal cleft associated with other activity signs of the macular neovascularization (MNV) were included. Structural optical coherence tomography (OCT) scans were evaluated to obtain anatomical measurements of prechoroidal cleft and PED at three different visits (T0, inactive MNV; T1, active MNV; T2, treated inactive MNV). The variations in size of the cleft and the PED were correlated with nAMD activity.

Results

Twenty-nine eyes from 27 patients were included. The subfoveal measurements showed a significant increase of prechoroidal cleft height and width from T0 to T1 (P < 0.05) and a subsequent decrease of the cleft height after treatment with anti-VEGF agents (P = 0.004). A similar significant trend was observed for the greatest prechoroidal cleft height and width, obtained assessing the whole OCT raster. In the multivariate analysis, the cleft height was significantly affected by both time (P = 0.001) and PED height (P < 0.0001). By contrast, the effect of fibrovascular tissue size within the PED was not significant. Visual acuity did not correlate with prechoroidal cleft size.

Conclusion

Prechoroidal cleft increased in association with MNV reactivation and decreased after treatment. Our results suggest that prechoroidal cleft could represent an accumulation of fluid actively exudating from the MNV and should be considered a sign of nAMD activity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00417-021-05384-w.

OUTER RETINAL TUBULATION MAY RESULT FROM FIBROSED TYPE 2 NEOVASCULARIZATION: Clinical Observations and Model of Pathogenesis

PURPOSE

To investigate the role of Type 2 macular neovascularization with subsequent subretinal fibrosis in the pathogenesis of outer retinal tubulation (ORT).

METHODS

We conducted a retrospective cohort study of patients with stabilized inactive exudative macular degeneration who had been treated with intravitreal injections of antivascular endothelial growth factor agents. Baseline fluorescein and optical coherence tomography images were included. Macular neovascularizations (MNVs) were classified by type and size. Consecutive optical coherence tomography images analyzed for ORT development.

RESULTS

One hundred forty-four eyes of 134 patients were included in this study. Sixty eyes presented with pure Type 1 MNV. Eighty-four eyes presented with some Type 2 component of MNV. In total, evidence of ORT is shown in 55 (38%) eyes. In the Type 1 group, 6.7% developed ORT. Outer retinal tubulation developed in 61% of eyes with some Type 2 component of the MNV. Among eyes that developed ORT, 92.7% presented with some Type 2 component. In a multivariate analysis, Type 2 membranes on optical coherence tomography (22.2 [6.1-80.8]; P < 0.001), larger MNV size {>1 DA (5.1 [1.1-24.2]; P = 0.041) and >1.5 DA (9.0 [1.8-44.0]; P = 0.007)}, and presence of subretinal fibrovascular material (3.1 [1.1-8.5]; P = < 0.03) are associated with higher odds of ORT formation. Once the ORT is formed, fibrosis was observed directly underlying the ORT on SD-optical coherence tomography in 70.9% of cases.

CONCLUSION

Type 2 membranes at presentation predict ORT formation. Fibrosis often underlies ORT. This suggests that contraction of Type 2 MNV-derived fibrosis may be important in ORT formation.

De-novo multilayering in fibrovascular pigment epithelial detachment

This study describes the occurrence of multilayered pigment-epithelial detachment (MLPED) as a De-novo phenomenon (DN-MLPED) and compare the features with multi-layering secondary to chronic anti-vascular endothelial growth factor (anti-VEGF) therapy (s-MLPED). We did a retrospective evaluation of spectral-domain optical coherence tomography (SD-OCT) features, treatment-profile, and visual-acuity (VA) outcomes in eyes with MLPED. Out of 17 eyes with MLPED, 7 eyes had DN-MLPED and 10 eyes had s-MLPED. There was no significant difference in baseline and final VA between the groups. At the final visit, no significant visual improvement was noted in both the groups, although a possible trend towards an improvement was seen in DN-MLPED eyes while the s-MLPED demonstrated a declining trend (DN-MLPED-LogMAR-BCVA: Baseline = 0.79 [∼ 20/123] ± 0.91; Final = 0.76 [∼ 20/115] ± 0.73; p = 0.87; s-MLPED-LogMAR BCVA: Baseline = 0.43 [∼ 20/54] ± 0.68; Final = 0.94 [∼ 20/174] ± 0.71; p = 0.06). Moreover, after presentation, the median number of injections in DN-MLPED eyes were significantly lower compared to s-MLPED eyes (DN-MLPED:4; s-MLPED:12; p = 0.03) (Median follow-up: DN-MLPED = 26 months; s-MLPED = 54 months; p = 0.15). Subretinal hyperreflective-material (SHRM) deposition heralded the onset of multilayering and was seen to progress in all DN-PED eyes and 1/4 eyes of s-MLPED. To conclude, MLPED is a unique form of cicatrizing fibrovascular-PED which can evolve denovo too. Long-standing disease with intermittent or low-grade activity can potentially explain this unique phenomenon. With fewer anti-VEGF therapy, the de-novo MLPED eyes show more visual stability as compared to s-MLPED eyes.

[Retinal pigment epithelial tear in age-related macular degeneration]

Retinal pigment epithelial tear (RPET) occurs in a number of diseases, most often in age-related macular degeneration (AMD). RPET develops in the setting of retinal pigment epithelium (RPE) detachment and represents a violation of the integrity of its monolayer accompanied by the formation of a demarcation line between the RPE atrophy area and RPE folds. Its incidence varies widely. In the earlier studies, diagnosis of RPET was performed using fluorescent angiography or angiography with indocyanine green (ICG-FA). The advent of optical coherence tomography made the detection of RPET easier and more accessible. The mechanism of RPET formation is quite polymorphic and ambiguous. Scientific literature contains descriptions of the occurrence of RPET when using both ranibizumab and aflibercept, and bevacizumab in equal proportions, implying that the drug choice does not affect the occurrence of complications. Continuous monitoring and adherence to anti-VEGF therapy leads to better anatomical and functional results in the long term, which is crucial for improving the quality of life of patients with age-related macular degeneration. This article reviews the literature and presents current data on RPET, identifies risk factors and mechanisms of its development, provides classification, and describes modern options for its diagnosis and treatment.

MORPHOLOGICAL AND FUNCTIONAL CHARACTERISTICS AT THE ONSET OF EXUDATIVE CONVERSION IN AGE-RELATED MACULAR DEGENERATION

PURPOSE

To characterize retinal morphology differences among different types of choroidal neovascularization and visual function changes at the onset of exudative age-related macular degeneration.

METHODS

In a post hoc analysis of a prospective clinical study, 1,097 fellow eyes from subjects with choroidal neovascularization in the study eye enrolled in the HARBOR trial were evaluated. The onset of exudation was diagnosed on monthly optical coherence tomography by two masked graders. At conversion as well as 1 month earlier, pigment epithelial detachment, intraretinal cystoid fluid, subretinal fluid, subretinal hyperreflective material, as well as ellipsoid zone and external limiting membrane loss were quantitatively analyzed. Hyperreflective foci, retinal pigment epithelial defects, haze and vitreoretinal interface status were evaluated qualitatively. Main outcome measures included visual acuity and rates of morphologic features at conversion and 1 month earlier.

RESULTS

New-onset exudation was detected in 92 eyes. One month before conversion, hyperreflective foci, pigment epithelial detachment, retinal pigment epithelial defects, and haze were present in the majority of eyes. At the onset of exudation, the volumes of intraretinal cystoid fluid, subretinal fluid, subretinal hyperreflective material and pigment epithelial detachment, and the areas of external limiting membrane and ellipsoid zone loss significantly increased. The mean vision loss was -2.2 letters. Pathognomonic patterns of the different choroidal neovascularization types were already apparent 1 month before conversion.

CONCLUSION

Characteristic choroidal neovascularization-associated morphological changes are preceding disease conversion, while vision loss at the onset of exudation is minimal. Individual lesion types are related to specific changes in optical coherence tomography morphology already before the time of conversion. Our findings may help to elucidate the pathophysiology of neovascular age-related macular degeneration and support the diagnosis of imminent disease conversion.

CHOROIDAL VASCULARITY INDEX IN YOUNG CHOROIDEREMIA PATIENTS

PURPOSE

To evaluate choroidal features in young patients affected by choroideremia (CHM).

METHODS

Young CHM patients and control subjects were recruited at the Eye Clinic in Florence. High-resolution choroidal imaging was obtained using swept-source optical coherence tomography with long optical coherence tomography scans (12 × 9 mm optical coherence tomography scans). We considered the subfoveal choroidal area within 9 mm of the optic disk in the horizontal plane and the subfoveal choroidal area within a 3-mm diameter centered over the fovea. The subfoveal choroidal thickness, total choroidal area, luminal area, stromal area, and choroidal vascularity index were assessed using the "ImageJ" software in both groups.

RESULTS

Eight patients (16 eyes; mean age, 19.3 ± 5.2 years) and seven control subjects (14 eyes; mean age, 19.0 ± 5.0 years) were included in this study. Best-corrected visual acuity was 20/20 in both eyes of seven CHM patients and in all control subjects and 20/25 in both eyes in one CHM patient. Mean subfoveal choroidal thickness did not differ between CHM patients and control subjects. Luminal area9mm, stromal area9mm, and total choroidal area9mm were reduced in patients compared with the control group. Luminal area3mm, stromal area3mm, and total choroidal area3mm did not differ between patients and control subjects. Choroidal vascularity index9mm and choroidal vascularity index3mm were not different between patients and control subjects.

CONCLUSION

There are no differences in the choroidal vascularity index between young CHM patients and control subjects; this result suggests a simultaneous, proportional impairment of both the stromal and vascular components of the choroid in the early stages of the disease.

Morphological features and prognostic significance of multilayered pigment epithelium detachment in age-related macular degeneration

AIMS

To investigate the structure of multilayered pigment epithelial detachment (m-PED) in neovascular age-related macular degeneration, and its association with visual prognosis and the progression of fibrotic scars at 12 months.

METHODS

We retrospectively analysed 68 eyes of 63 patients with m-PED that included a prechoroidal cleft. The compartments within m-PED were divided into neovascular tissue (layer 1), a hyper-reflective band (layer 2), and a prechoroidal cleft (layer 3). Clinical variables were compared between patients manifesting layer 2 and those who did not. Multiple regression analyses were used to find the factors related to visual outcome and fibrotic scar formation.

RESULTS

Layer 2 was detected in 38 (55.9 %) of 68 eyes. With continuous treatment, the group with layer 2 showed gradual visual deterioration (p<0.001 at month 12), while the group without layer 2 showed visual improvement (p<0.001 at month 12). In the group with layer 2, the thickness of layer 2 significantly increased, and in the group without layer 2, if it formed, it increased gradually (p=0.004 at month 12). In both groups, other layers significantly decreased by month 12. The presence of layer 2 at baseline was significantly associated with a poor visual outcome (p=0.009) and fibrotic scar formation (p=0.023).

CONCLUSIONS

The m-PED with layer 2 had a higher risk of fibrotic scar formation and was associated with a poor visual prognosis. Layer 2 may be an early stage precursor of a fibrotic scar.

Predicting retinal pigment epithelium remodelling and its functional impact

PURPOSE

To identify predictive factors for RPE tear remodelling and its correlation with functional and morphological outcomes.

METHODS

Retrospective longitudinal study of patients with retinal pigment epithelium (RPE) tears secondary to age-related macular degeneration (AMD). Imaging was performed using spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF). RPE layer integrity in the RPE-denuded area was examined with SD-OCT, and variation in the RPE-denuded homogeneous hypofluorescent area was examined with FAF over time for each case (eye). Patients were divided in two groups, according to the presence (Rem) or absence (No Rem) of evidence of RPE tear remodelling. Data were collected at three different time points: at baseline (at diagnosis of exudative AMD), at RPE tear diagnosis, and at the last available follow-up. Using SD-OCT, the following parameters were evaluated: type of CNV, type of PED and its dimensions, presence of subretinal (SRF) or intraretinal (IRF) fluid, central retinal thickness (CRT), presence and location of hyperreflective dots, and dimension and location of RPE tear.

RESULTS

This study included 32 eyes from 31 patients (19 female and 12 male), with RPE tears secondary to AMD. RPE remodelling after tear development was evident in 17 (53.1%) eyes after 7 [1-59] months. Anatomical recovery was associated with a younger age at RPE tear diagnosis (73 ± 7 vs. 81 ± 7 years old, p=0.01), smaller and narrower retinal pigment epithelial detachment (PED) at tear diagnosis (height 369 vs. 602 μm, p=0.02; width 2379 vs. 3378 μm, p=0.04), and the presence of SRF at tear diagnosis (94% vs. 53%, p=0.02). After adjusting for other covariates, a younger age at RPE tear diagnosis maintained significant association with RPE tear remodelling. RPE tear remodelling did not correlate with a better visual outcome at last follow-up (43 ± 22.8 vs. 34 ± 23.8 ETDRS letters, p=0.30). Final VA was directly proportional to VA at tear diagnosis (r= 0.654; p<0.001) and correlated negatively with PED width at tear diagnosis (r = -0.388; p=0.03).

CONCLUSION

RPE remodelling was evident in half of our sample and was associated with a younger age, smaller and narrower PED at RPE tear diagnosis, and presence of SRF also at tear diagnosis. Nevertheless, this structural recovery did not result in a better functional outcome.

Clustering of eyes with age-related macular degeneration or pachychoroid spectrum diseases based on choroidal thickness profile

Choroidal changes have been suggested to be involved in the pathophysiology of both age-related macular degeneration (AMD) and pachychoroid spectrum diseases (PSD). To find out the choroidal characteristics of each disease groups, various groups of AMD and PSD were classified into several clusters according to choroidal profiles based on subfoveal choroidal thickness (CT), peripapillary CT, the ratio of subfoveal CT to peripapillary CT and age. We retrospectively analyzed 661 eyes, including 190 normal controls and 471 with AMD or PSDs. In the AMD groups, eyes with soft drusen or reticular pseudodrusen were belonged to the same cluster as those with classic exudative AMD (all p < 0.001). However, eyes with pachydrusen were not clustered with eyes from other AMD groups; instead, they were classified in the same cluster as eyes from the PSD group (all p < 0.001). In the PSD group, eyes with pachychoroid neovasculopathy were grouped in the same cluster of those with polypoidal choroidal vasculopathy (p < 0.001). The cluster analysis based on the CT profiles, including subfoveal CT, peripapillary CT, and their ratio, revealed a clustering pattern of eyes with AMD and PSDs. These findings support the suggestion that pachydrusen has the common pathogenesis as PSD.

Nasal displacement of retinal vessels on the optic disc in glaucoma associated with a nasally angled passage through lamina cribrosa

To investigate nasal displacement of central retinal vessel (CRV) on the optic nerve head (ONH) in glaucoma in association with its passage through lamina cribrosa (LC). This cross-sectional study included 113 eyes with glaucoma and 60 normal eyes. Horizontal spectral-domain optical coherence tomography (SD-OCT) scans of the ONH were acquired, and point where CRV emerged on the ONH surface was defined as the position of the CRV. Next, radial scans of the ONH were acquired, and angle of the CRV passing through the LC was measured. These parameters were compared between glaucomatous and normal eyes by t-test, and their relationship with possible confounders was assessed by multiple regression analyses. In glaucoma, CRV was significantly more nasally displaced than it was in normal eyes (66.0 ± 8.6 vs. 54.3 ± 9.5, P < 0.0001), and eyes with more vessel displacement exhibited significantly worse glaucomatous visual field defects (P = 0.0004). Greater nasal displacement of the CRV was significantly associated with a more nasally angled path through the LC (rs = 0.569, P < 0.0001). By using SD-OCT, we confirmed that nasal displacement of the CRV on the ONH was associated with glaucoma and was induced by its nasally angled path through the LC.

Choroidal vascularization and adrenergic innervation qualitative findings obtained with induced fluorescence preparations and optical coherence tomography angiography: possible correlations and perspectives

Background

Recent advances in optical coherence tomography (OCT) technology allow a more accurate choroidal visualization. The aim of this study is to provide histochemical analysis with induced fluorescence images of the choroidal stromal, vascular and nerve network, highlighting possible correspondences with OCT and OCT angiography (OCT-A) analysis.

Methods

The material examined with a histochemical process of induced fluorescence through condensation of biologically active monoamines with glyoxylic acid was obtained from 6 eyes enucleated for malignant melanoma and ciliary body neoplasia. The resulting images have been qualitatively compared with OCT and OCT-A choroidal images obtained from 10 volunteers, in order to identify possible relationships. Choriocapillary segmentation was performed automatically through the embedded analysis software, while segmentation of Sattler’s and Haller’s layers was performed through a manual method.

Results

Histochemical analysis provided accurate visualization of choroidal adrenergic innervation across all layers and its relationships with blood vessels and melanocytes. The above structures were not visualized at OCT and OCT-A which provided good visualization of blood vessels in Sattler’s and Haller’s layers as well-delimited hyporeflective areas. Decorrelation signal was not detected in OCT-A analysis due to low blood flow velocity in external choroidal layers.

Conclusions

The choroid is an extremely dynamic structure which deserves to be analyzed in vivo since it is involved in the pathogenesis of several ocular conditions. Direct evaluation of the activity of choroidal nerves and melanocytes is still not possible with OCT and OCT-A, even if they are capable of providing a satisfactory representation of choroidal vascularization.

How does nepafenac affect the choroidal thickness after uneventful cataract surgery?

PURPOSE

To investigate the effects of topical nepafenac on choroidal thickness (CT) following uneventful phacoemulsification surgery (UPS) using enhanced depth imaging optical coherence tomography (EDI-OCT).

METHODS

This prospective study included 45 randomly selected eyes (23 eyes of 23 patients used nepafenac (nepafenac group) and 22 eyes of 22 control patients did not use nepafenac (nepafenac-free group)) undergoing small-incision UPS. All participants underwent full ophthalmologic examination. CT measurements were performed at subfoveal, 1.0 mm temporal, and 1.0 mm nasal using the EDI-OCT preoperatively, 1 day, 1 week, and 1 month postoperatively.

RESULTS

The mean subfoveal, nasal, and temporal CT in the nepafenac-free group had changed from 268.95 ± 63.59 μm to 283.36 ± 65.63 μm, 237.22 ± 64.09 μm to 253.09 ± 67.27 μm, and 235.95 ± 75.22 μm to 259.09 ± 63.66 μm preoperatively to 1 month postoperatively, respectively (p < 0.001, p < 0.001, p < 0.001, respectively). The mean subfoveal, nasal, and temporal CT in the nepafenac group had changed from 259.65 ± 55.99 μm to 276.65 ± 59.21 μm, 236.34 ± 55.40 μm to 251.00 ± 62.39 μm, and 247.56 ± 50.88 μm to 261.13 ± 53.73 μm preoperatively to 1 month postoperatively, respectively (p < 0.001, p < 0.001, p < 0.001, respectively). The postoperative CT continued to increase significantly during the follow-up period in two groups. However, compared to the change from baseline to month 1, there was not a statistically significant difference between the groups at subfoveal, nasal, and temporal CT (p: 0.633, p: 0.865, and p: 0.328, respectively).

CONCLUSION

UPS may cause a significant increase in CT. Although increasing in the CT was lower in the nepafenac group than the nepafenac-free group, there was not a statistically significant difference between the groups.

Enhanced depth imaging in swept-source optical coherence tomography: Improving visibility of choroid and sclera, a masked study

Purpose

To compare enhanced depth imaging in swept-source optical coherence tomography and non–enhanced depth imaging optical coherence tomography in their ability to capture choroidal and scleral details.

Methods

Averaged foveal B-Scans were obtained from 40 eyes of 20 healthy volunteers by swept-source optical coherence tomography with and without enhanced depth imaging. Visibility and contrast of vascular details within the choroid, choroidoscleral junction, and sclera were evaluated by masked readers using an ordinal scoring scale. Outcomes were analyzed using the Wilcoxon signed rank-sum test.

Results

Visibility of the choroidal vascular details ( Z = 5.94, p < .001), the choroidoscleral junction ( Z = 5.85, p < .001), and the sclera ( Z = 6.80, p < .001) was significantly higher with enhanced depth imaging than with non–enhanced depth imaging swept-source optical coherence tomography. Similarly, image contrast was significantly higher with enhanced depth imaging than with non–enhanced depth imaging swept-source optical coherence tomography for the choroidal vascular details ( Z = 9.47, p < .001), for the choroidoscleral junction ( Z = 9.28, p < .001), and for the sclera ( Z = 9.42, p < .001).

Conclusion

Enhanced depth imaging applied to swept-source optical coherence tomography–averaged foveal B-scans enhances visualization of the choroidal details, of the choroidoscleral junction, and of the sclera. This novel modality can easily be implemented in clinics and could improve our understanding of conditions involving the choroid or the sclera.

Diagnosing Optic Disc Drusen in the Modern Imaging Era: A Practical Approach

Optic disc drusen (ODD) are a well-recognised cause of an elevated optic disc appearance. When visible with ophthalmoscopy and fundus photography, ODD are readily identified. Yet, in more subtle cases of ODD, ancillary testing may be needed to render the diagnosis. Facilitating the diagnosis of ODD has clinical relevance, because affected individuals may otherwise undergo unnecessary costly and invasive investigations to rule out raised intracranial pressure and other causes of optic disc oedema. In this review, the role of established and emerging optical coherence tomography (OCT) techniques in the diagnosis and management of ODD cases is reviewed. A practical approach is taken to explain how to optimise use of commercially available OCT technology in the clinical setting. Optical coherence tomography provides many advantages over other imaging modalities in the diagnosis of ODD, including the ability to correlate retinal measures of neuroaxonal structure with drusen characteristics. Earlier spectral domain OCT techniques, however, were hindered by poor penetrance. In the modern imaging era, enhanced depth imaging OCT and swept source OCT enable higher resolution of ODD and other optic nerve head structures that might otherwise be mistaken for drusen. Ongoing studies featuring OCT angiography indicate that this technique may provide complementary information about microvascular supply that correlate with structural measures of optic nerve injury. Advances in OCT will continue to improve diagnostic accuracy and inform clinical understanding regarding structure-function correlations germane to the longitudinal follow up of ODD patients.

The Application of Enhanced Depth Imaging Spectral-Domain Optical Coherence Tomography in Macular Diseases

The choroid plays an essential role in the pathogenesis of various posterior segment diseases. However, traditional imaging methods still have limited cross-sectional observation of choroid. Enhanced depth imaging in spectral-domain optical coherence tomography (EDI SD-OCT) uses a closer scanning position to the eye to create an inverted SD-OCT image with the advantage of better depth sensitivity, which can observe choroidal structure and measure choroidal thickness (CT) accurately. At present, more and more choroidal thickness measurements have been made in normal and pathologic states, in order to understand the pathogenesis and differential diagnosis and prognosis of various diseases, especially for macular lesions. This paper would review relevant original literatures published from January 1, 2008, to February 1, 2020, to evaluate the relationship between the changes of CT with EDI SD-OCT and macular diseases.

Retinal Pigment Epithelial Detachment in Age-Related Macular Degeneration

Retinal pigment epithelial detachment is defined as a separation of the retinal pigment epithelium from the inner collagenous layer of Bruch’s membrane. It is a common manifestation in both dry and wet types of age-related macular degeneration. This review aims to provide a comprehensive guide to the pathophysiology, clinical and imaging characteristics, natural course and treatment of the various types of pigment epithelial detachments in order to assist in diagnosis and management of this important feature of age-related macular degeneration.

Reliability and Reproducibility of Pigment Epithelial Detachment Volume Measurements in AMD Using a New Tool: ReVAnalyzer

BACKGROUND AND OBJECTIVE

To describe and present the reliability and reproducibility of a new software, Retinal Volume Analyzer (ReVAnalyzer), for pigment epithelium detachment (PED) volume quantification.

PATIENTS AND METHODS

This is a retrospective study including patients with PEDs secondary to exudative age-related macular degeneration (AMD). Macular volume scans on spectral-domain optical coherence tomography on enhanced depth imaging mode were performed in all eyes. Image batches were then exported in .xml format to the ReVAnalyzer software. A semiautomated PED volume measurement was performed by three independent readers (RBG, VC, OS) twice, at the beginning and end of a 15-day period. Bland-Altman assessment for agreement was used to compare intra- and interobserver observations.

RESULTS

Twenty eyes of 20 patients presenting with PED were analyzed. Bland-Altman analysis indicated a good agreement between inter- and intraobserver measurements. The intraclass correlation coefficient for intraobserver PED volume measurements and between the three observers (interobserver) was greater than 0.99, demonstrating high reproducibility and consistency of the methodology.

CONCLUSIONS

ReVAnalyzer is a reliable tool that can assist in the analysis of PED volume with high reproducibility. This type of specific retinal volume analysis can be of help for monitoring disease activity and therapeutic response in AMD. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e242-e249.].

Feasibility and Safety of a Coaxial Dual-Wavelength Optical Coherence Tomography Apparatus

PURPOSE

To evaluate the feasibility and safety of a coaxial dual-wavelength optical coherence tomography (OCT) device (marked as Hydra-OCT).

METHODS

Healthy participants without ocular pathology underwent retinal imaging using the Hydra-OCT allowing for simultaneous measurement of retinal scanning of 840 and 1,072 nm wavelength. Before and after measurement, best-corrected visual acuity and patients' comfort were assessed. Representative OCT images from both wavelengths were compared by 5 independent graders using a subjective grading scheme.

RESULTS

A total of 30 eyes of 30 participants (8 females and 22 males) with a mean age of 26.5 years (range from 19 to 55 years) were included. Dual-wavelength image acquisition was made possible in each subject. The participant's effort and comfort assessment using the Hydra-OCT imaging revealed an equivalent value as compared to the commercially available OCT machine. No adverse events were reported, and visual acuity was not altered by the Hydra-OCT. Imaging between the systems was comparable.

CONCLUSIONS

This study provides evidence for the feasibility and safety of a coaxial dual-wavelength OCT imaging method under real-life conditions. The novel Hydra-OCT imaging device may offer additional insights into the pathology of retinal and choroidal diseases.

Influence of pigment epithelial detachment on visual acuity in neovascular age-related macular degeneration

Pigment epithelial detachment (PED), the anatomical separation of the retinal pigment epithelium from the Bruch membrane, is common in many chorioretinal diseases, including neovascular age-related macular degeneration. PED is present in about 30% to 80% of neovascular age-related macular degeneration patients based on the CATT, EXCITE, and VIEW studies. The influence of PED on visual acuity is controversial as a result of inconsistent results reported by various studies. With advances in imaging technologies, it is possible to evaluate not only the presence or absence of PED, but also detailed quantitative parameters, such as height, width, greatest linear diameter, area, volume, and reflectivity within the PED. We performed a comprehensive literature review to evaluate the relationship of PED with visual acuity. In summary, the presence or persistence of a PED may still be compatible with relatively good visual acuity. There is no strong evidence that the presence of a PED or aspects of its morphology has a significant impact on visual acuity. The presence of a PED may be predictive of the need for more regular treatment. More well-designed studies with standardized PED definitions and classifications are needed to evaluate the relationship between PED and visual acuity.

Dimple in vascularized serous pigment epithelial detachment secondary to neovascular age-related macular degeneration

BACKGROUND

To describe the "dimple," a previously unreported structural optical coherence tomography (OCT) finding in vascularized serous pigment epithelial detachment (PED) secondary to neovascular age-related macular degeneration (AMD).

METHODS

Retrospective, longitudinal, case series study. Clinical charts and multimodal imaging including OCT (structural and angiography) and dye-based angiography (fluorescein and indocyanine green) examinations of patients with dimple-defined as a localized invagination of the vascularized serous PED-were analyzed in 2 high-volume referral centers.

RESULTS

Nineteen eyes of 18 patients were included. Mean follow-up was at 64.1 ± 35.8 months. The greater basal and height diameters of the vascularized serous PED were respectively 3425.8 ± 1049.6 μm and 667.1 ± 279.9 μm at baseline and 3076.2 ± 1649.9 μm (p = 0.8) and 368.3 ± 295.1 at last follow-up (p = 0.0006). OCT analysis identified 2 phenotypes of dimple: type 1 or ("top denting") (9 eyes) and type 2 (or "side denting") (10 eyes). Both phenotypes are associated with hyper-reflective holding sub-retinal pigment epithelium (RPE) band encompassing the posterior face of the RPE and extending to the Bruch's membrane. Hyper-reflective holding band is not correlated with angiographic signs of neovascular tissue in all cases. During follow-up, no case of RPE tear was observed.

CONCLUSIONS

We describe the characteristics of the dimple and its association with hyper-reflective holding sub-RPE bands in the context of large vascularized serous PED in neovascular AMD. The presence of a dimple does not seem to be an additional risk factor for the development of RPE tearing in high-risk PED secondary to neovascular AMD.

Consensus Nomenclature for Reporting Neovascular Age-Related Macular Degeneration Data: Consensus on Neovascular Age-Related Macular Degeneration Nomenclature Study Group

PURPOSE

To establish a process to evaluate and standardize a state-of-the-art nomenclature for reporting neovascular age-related macular degeneration (AMD) data.

DESIGN

Consensus meeting.

PARTICIPANTS

An international panel of retina specialists, imaging and image reading center experts, and ocular pathologists.

METHODS

During several meetings organized under the auspices of the Macula Society, an international study group discussed and codified a set nomenclature framework for classifying the subtypes of neovascular AMD and associated lesion components.

MAIN OUTCOME MEASURES

A consensus classification of neovascular AMD.

RESULTS

The study group created a standardized working definition of AMD. The components of neovascular AMD were defined and subclassified. Disease consequences of macular neovascularization were delineated.

CONCLUSIONS

The framework of a consensus nomenclature system, a definition of AMD, and a delineation of the subtypes of neovascular AMD were developed. Establishing a uniform set of definitions will facilitate comparison of diverse patient groups and different studies. The framework presented is modified and updated readily, processes that are anticipated to occur on a periodic basis. The study group suggests that the consensus standards outlined in this article be used in future reported studies of neovascular AMD and clinical practice.

Choroidal changes in intermediate age-related macular degeneration patients with drusen or pseudodrusen

Reticular pseudodrusen are associated with a thinner choroid. The aim of our study was to determine the differences in central choroidal thickness and choriocapillaris vascular flow area between eyes with and without reticular pseudodrusen using swept-source optical coherence tomography and swept-source optical coherence tomography angiography. We conducted a retrospective case control study which included 27 eyes from 27 consecutive patients with intermediate age-related macular degeneration and 17 eyes from 17 healthy participants. Complete ophthalmic examinations were carried out including axial length measurements; fundus color retinography; fundus autofluorescence; swept-source optical coherence tomography and swept-source optical coherence tomography angiography; central choroidal thickness and choriocapillaris vascular flow area. Patients were classified as no reticular pseudodrusen, mild reticular pseudodrusen, and severe reticular pseudodrusen. Mean central choroidal thickness in patients exhibiting severe reticular pseudodrusen (110 ± 56 μm) was significantly smaller than in patients with no reticular pseudodrusen (201 ± 76 μm, p < 0.01). Mean choriocapillaris vascular flow area in severe reticular pseudodrusen patients (45.2% ± 3.0%) was also significantly less than in patients with no (47.9% ± 1.6%, p < 0.001) and mild reticular pseudodrusen (47.7% ± 1.0%, p < 0.05). Stepwise multiple regression models confirmed the association of reticular pseudodrusen with central choroidal thickness (p < 0.001) and choriocapillaris vascular flow area (p < 0.01) even after accounting for age, axial length, and refractive error. Soft drusen were not associated with changes in either central choroidal thickness (p = 0.13) nor choriocapillaris vascular flow area (p = 0.29). A significant, positive relationship was found between central choroidal thickness and choriocapillaris vascular flow area (r = 0.44, p = 0.01). Therefore, both central choroidal thickness and choriocapillaris vascular flow area are decreased in eyes with reticular pseudodrusen, as compared to healthy eyes and intermediate age-related macular degeneration eyes not exhibiting reticular pseudodrusen. In addition, central choroidal thickness and choriocapillaris vascular flow area are related, and the reduction of either is directly associated to the severity of reticular pseudodrusen. Further studies are needed to assess the clinical significance of these findings.

OUTCOME OF INTRAVITREAL AFLIBERCEPT FOR REFRACTORY PIGMENT EPITHELIAL DETACHMENT WITH OR WITHOUT SUBRETINAL FLUID AND SECONDARY TO AGE-RELATED MACULAR DEGENERATION

PURPOSE

To investigate the outcomes of intravitreal aflibercept in refractory pigment epithelial detachment (PED) with or without subretinal fluid (SRF) in patients with neovascular age-related macular degeneration.

METHODS

A prospective, nonrandomized, interventional case series involved 40 patients with persistent vascularized PED previously treated with at least 3 injections of intravitreal bevacizumab or ranibizumab. Intravitreal aflibercept was administered as 3 initial loading doses every 4 weeks, followed by pro re nata retreatment every 8 weeks over 48 weeks. Pigment epithelial detachment was classified into solid-, hollow-, or mixed-type according to the reflective properties visualized using optical coherence tomography. The mean changes in best-corrected visual acuity, central subfield thickness, and the volumes of SRF and PED were analyzed.

RESULTS

The PED volume (baseline: 0.43 ± 0.55 mm) significantly reduced to 0.23 ± 0.32 mm at Week 8 (P = 0.003) and increased to 0.36 ± 0.41 mm at Week 48 (P = 0.345). The SRF volume (baseline: 0.52 ± 0.64 mm) significantly reduced to 0.24 ± 0.43 mm at Week 48 (P = 0.021). The mean baseline best-corrected visual acuity was 20/75 (47.5 letters); it showed no significant difference at Week 48 (+4.4 letters; P = 0.125). The baseline central subfield thickness was 323.2 ± 92.3 μm; it significantly reduced to 281.2 ± 90.7 μm at Week 48 (P = 0.001). In solid-type PEDs, there were poorer improvements in central subfield thickness, best-corrected visual acuity, and the volumes of the SRF and PED, with newly developed intraretinal cysts.

CONCLUSION

Intravitreal aflibercept in treatment-resistant neovascular age-related macular degeneration led to significant reduction in PED and SRF volume, central subfield thickness, and best-corrected visual acuity preserved, over 12 months. However, solid-type PED showed less improvement than hollow- or mixed-type PED.

Lateral elongation of flat irregular pigment epithelial detachment: A novel optical coherence tomography biomarker in polypoidal choroidal vasculopathy

Purpose

To explore novel Optical Coherence Tomography (OCT) biomarkers and precursor lesions in Polypoidal Choroidal Vasculopathy (PCV).

Methods

This retrospective cohort study included 76 treatment naïve fellow eyes of PCV. Focus was given to analyse the various morphological changes in the clinically unaffected fellow retina during the follow-up period.

Results

11 fellow eyes (14.47%) developed disease activity in the form of Sub Retinal Fluid (SRF) or Intra Retinal Fluid (IRF) within a mean follow-up of 17 months. All 11 eyes (100%) showed the presence of flat irregular pigment epithelial detachment (FIPED) and a peculiar property of lateral elongation of FIPED during disease activity. A positive correlation with the disease progression was found for the same (P < 0.0001). The mean horizontal dimension of the flat irregular PED at the enrolment was 1984 ± 376u and the mean expansion of FIPED at SRF formation was 461 ± 152u. ICG taken at the time of disease activity in the fellow eye revealed branching vascular network (BVN) in 9 (81.8%) eyes, polyps in 7 (63.6%) eyes, a combination of both in 5 (45.4%) eyes. Type one BVN with interconnecting channels showed faster disease progression than type two BVN. Eye tracking ICG illustrated that BVN corresponded to the FIPED in OCT and polypoidal lesions developed at the end of expanding FIPED.

Conclusion

Flat irregular pigment epithelial detachment with its characteristic property of lateral elongation may be considered as a precursor lesion for PCV and as a novel OCT biomarker for the disease activity. Fellow eyes with FIPED need close monitoring to identify development of disease activity at the earliest.

Subretinal pigment epithelium fibrotic tissue morphological changes after a single anti-vascular endothelial growth factor injection in age-related macular degeneration

Aims

To demonstrate and evaluate the morphological changes of multilayered fibrovascular pigment epithelial detachment (PED) to a single anti-vascular endothelial growth factor (VEGF) injection in age-related macular degeneration (AMD).

Methods

We retrospectively analysed the morphological changes of 30 eyes with exudative AMD showing fibrotic multilayered PED, between two consecutive visits. All patients had one anti-VEGF intravitreal injection at the first visit. We quantitatively analysed the different compartments within the PED and their morphological response.

Results

The mean follow-up time interval between the first and the second visit was 32.46±4.64 days. We defined three optical coherence tomography zones within the PED: a subretinal pigment epithelium inhomogeneous hyporeflective space (layer 1), a hyper-reflective band beneath layer 1 (layer 2), and a hyporeflective space between the Bruch’s membrane and layer 2 (layer 3). The mean height of layer 1 was 142±44.63 and 99.30±39.79 µm at visits 1 and 2, respectively. The mean thickness of layer 2 was 101.42±46.66 and 82.76±35.24 µm at visits 1 and 2, respectively. The mean height of layer 3 was 35.77±32.77 and 5.66±8.68 µm at visits 1 and 2, respectively (p=0.009). The mean height change for layer 1 was statistically significantly higher than for layer 2 (p=0.0002).

Conclusions

Fibrovascular PED was compartmented into three layers with different reflectivities that morphologically responded differently to a single anti-VEGF injection. Layer 2 had a statistically significantly lower response compared with layer 1, suggesting the hypothesis of a fibrotic component in layer 2.

Vascularized drusen: a cross-sectional study

Background

To investigate whether neovascularization may arise and be detectable in drusen, as reported in histopathologic studies, by OCTA prior to developing exudation and to assess its prevalence in a cohort of patients with intermediate AMD.

Methods

Retrospective cross-sectional study of 128 patients with intermediate AMD recruited as part of a separate ongoing clinical trial conducted at multiple large tertiary referral retina clinics. One hundred and twenty-eight consecutive patients with exudative AMD in one eye and intermediate non-exudative AMD in the fellow eye were enrolled and analyzed between September 2015 and March 2017.

Results

SD-OCTA identified vascularization within drusen in 7 of 128 eyes, for a prevalence of 5.5%. A total of 12 instances of vascularized drusen were noted. Out of the 12 vascularized drusen noted, 7 were located in the parafoveal region or subfoveal region and 5 was in the extrafoveal region. 9 of 12 instances of vascularized drusen exhibited a uniform sub-RPE hyperreflectivity, whilst 3 of 12 exhibited more heterogenous reflectivity. In all 12 instances, FA images failed to identify the neovascular nature of vascularized drusen.

Conclusions

Our results demonstrate the utility of SD-OCTA for the diagnosis of vascularized drusen in patients with intermediate non-exudative AMD. Longitudinal studies are needed to delineate the evolution and conversion risk of these lesions over time, which can be of substantial clinical relevance.

Deep Learning for Prediction of AMD Progression: A Pilot Study

Purpose

To develop and assess a method for predicting the likelihood of converting from early/intermediate to advanced wet age-related macular degeneration (AMD) using optical coherence tomography (OCT) imaging and methods of deep learning.

Methods

Seventy-one eyes of 71 patients with confirmed early/intermediate AMD with contralateral wet AMD were imaged with OCT three times over 2 years (baseline, year 1, year 2). These eyes were divided into two groups: eyes that had not converted to wet AMD (n = 40) at year 2 and those that had (n = 31). Two deep convolutional neural networks (CNN) were evaluated using 5-fold cross validation on the OCT data at baseline to attempt to predict which eyes would convert to advanced AMD at year 2: (1) VGG16, a popular CNN for image recognition was fine-tuned, and (2) a novel, simplified CNN architecture was trained from scratch. Preprocessing was added in the form of a segmentation-based normalization to reduce variance in the data and improve performance.

Results

Our new architecture, AMDnet, with preprocessing, achieved an area under the receiver operating characteristic (ROC) curve (AUC) of 0.89 at the B-scan level and 0.91 for volumes. Results for VGG16, an established CNN architecture, with preprocessing were 0.82 for B-scans/0.87 for volumes versus 0.66 for B-scans/0.69 for volumes without preprocessing.

Conclusions

A CNN with layer segmentation-based preprocessing shows strong predictive power for the progression of early/intermediate AMD to advanced AMD. Use of the preprocessing was shown to improve performance regardless of the network architecture.

Peripapillary and macular choroidal thickness before and after phenylephrine instillation

OBJECTIVES

We investigated the effects of topical phenylephrine 2.5% instillation on choroidal thickness (CT), peripapillary choroidal thickness (pCT) and retinal nerve fibre layer (RNFL).

METHODS

Healthy control patients underwent enhanced depth imaging (EDI) by spectral-domain optical coherence tomography (OCT) before and 30 min after phenylephrine instillation, using eye-tracking and follow-up software. Changes in 14 different locations of CT, 2 locations of pCT and RNFL were assessed.

RESULTS

The study included 119 eyes of 62 patients (19 males and 43 females), with a mean age of 59.8 ± 15.3 years (range: 26-88 years). Within 30 min after instillation, the mean subfoveal CT both in vertical and horizontal scan were significantly thinned (p = 0.005 and p  = 0.018, respectively). In total, 1500, 1000 and 500 µm temporal CT measurements showed also a significant thinning (p = 0.021, p  = 0.037 and p = 0.020, respectively), as well as 500 µm both superior (p  = 0.045) and inferior (p  = 0.009). 1500, 1000 and 500 µm nasal CT, and 1500 and 1000 µm CT superior and inferior measurements showed no significant thinning after phenylephrine instillation. pCT was significantly thinned after phenylephrine in both superior (p = 0.016) and inferior (p = 0.050) measurements. RNFL analysis did not significantly change after phenylephrine instillation (p =  0.209).

CONCLUSIONS

A significant thinning of CT and pCT occurred following phenylephrine instillation. Future studies analysing CT and pCT should detail if this mydriatic agent was used or not.

Retinal pigment epithelial tears

A retinal pigment epithelial (RPE) tear is a well-known complication of retinal pigment epithelial detachments (PED) and may cause a significant visual impairment. The most common cause is a vascularized PED in patients with exudative age-related macular degeneration (AMD). The development of diagnostic imaging techniques brings us closer to the etiology and pathophysiological mechanisms of this entity, offering us new strategies for treatment and follow-up. The advent of intravitreal antiangiogenic treatment (anti-VEGF) has led to an increase in the number of reported cases of RPE tears, which are an important vision-limiting factor during treatment. However, RPE tears may occur spontaneously or as a consequence of thermal laser treatment, photodynamic therapy or anti-VEGF therapy. It is accepted that the mechanism of RPE tears is multifactorial. The optimization of the functional outcome of this complication has been described with continuous treatment with antiangiogenic drugs. The goal of the present review is to evaluate the incidence, risk factors and treatment of RPE tears.