Fundus Autofluorescence in Age-related Macular Degeneration

Retinoic acid related orphan receptor α is a genetic modifier that rescues retinal degeneration in a mouse model of Stargardt disease and Dry AMD

Degeneration of the macula is associated with several overlapping diseases including age-related macular degeneration (AMD) and Stargardt Disease (STGD). Mutations in ATP Binding Cassette Subfamily A Member 4 (ABCA4) are associated with late-onset dry AMD and early-onset STGD. Additionally, both forms of macular degeneration exhibit deposition of subretinal material and photoreceptor degeneration. Retinoic acid related orphan receptor α (RORA) regulates the AMD inflammation pathway that includes ABCA4, CD59, C3 and C5. In this translational study, we examined the efficacy of RORA at attenuating retinal degeneration and improving the inflammatory response in Abca4 knockout (Abca4-/-) mice. AAV5-hRORA-treated mice showed reduced deposits, restored CD59 expression and attenuated amyloid precursor protein (APP) expression compared with untreated eyes. This molecular rescue correlated with statistically significant improvement in photoreceptor function. This is the first study evaluating the impact of RORA modifier gene therapy on rescuing retinal degeneration. Our studies demonstrate efficacy of RORA in improving STGD and dry AMD-like disease.

OCT Prognostic Biomarkers for Progression to Late Age-related Macular Degeneration: A Systematic Review and Meta-analysis

TOPIC

To evaluate which OCT prognostic biomarkers best predict the risk of progression from early/intermediate to late age-related macular degeneration (AMD).

CLINICAL RELEVANCE

Among > 100 OCT prognostic biomarkers for AMD, it is unclear which are the most relevant for clinicians and researchers to focus on. This review evaluated which OCT biomarkers confer the greatest magnitude of prediction for progression to late AMD.

METHODS

Study protocol was registered on PROSPERO (CRD42023400166). PubMed and Embase were searched from inception to March 2, 2023, and eligible studies assessed following the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. The primary outcome was any quantified risk of progression from treatment-naive early/intermediate AMD to late AMD, including hazard ratios (HRs), odds ratios (ORs), and standardized mean differences (at baseline, between eyes with versus without progression), subgrouped by each OCT biomarker. Further meta-analyses were subgrouped by progression to geographic atrophy or neovascularization.

RESULTS

A total of 114 quantified OCT prognostic biomarkers were identified. With high GRADE certainty of evidence, the greatest magnitudes of prediction to late AMD belonged to: external limiting membrane abnormality (OR, 15.42 [7.63, 31.17]), ellipsoid zone abnormality (OR, 10.8 [4.58, 25.46]), interdigitation zone abnormality (OR, 7.68 [2.57, 23]), concurrent large drusen and reticular pseudodrusen (HR, 6.73 [1.35, 33.65], hyporeflective drusen cores (HR, 2.48 [1.8, 3.4]; OR 1.85 [1.29, 2.66]), intraretinal hyperreflective foci (IHRF; HR, 2.16 [0.92, 5.07]; OR 5.08 [3.26, 7.92]), and large drusen (HR, 2.01 [1.35, 2.99]); OR, 1.98 [1.27, 3.08]). There was greater risk of geographic atrophy for IHRF and hyporeflective drusen cores (P < 0.05), and neovascularization for ellipsoid zone abnormality (P < 0.05). Other OCT biomarkers such as drusenoid pigment epithelium detachment, shallow irregular retinal pigment epithelium elevations, and nascent geographic atrophy exhibited large magnitudes of risk but required further studies for validation.

CONCLUSION

This review synthesizes the 6 most relevant OCT prognostic biomarkers for AMD with greater predictive ability than large drusen alone, for clinicians and researchers to focus on. Further study is required to validate other biomarkers with less than high certainty of evidence, and assess how the copresence of biomarkers may affect risks.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

AI-based support for optical coherence tomography in age-related macular degeneration

Artificial intelligence (AI) has emerged as a transformative technology across various fields, and its applications in the medical domain, particularly in ophthalmology, has gained significant attention. The vast amount of high-resolution image data, such as optical coherence tomography (OCT) images, has been a driving force behind AI growth in this field. Age-related macular degeneration (AMD) is one of the leading causes for blindness in the world, affecting approximately 196 million people worldwide in 2020. Multimodal imaging has been for a long time the gold standard for diagnosing patients with AMD, however, currently treatment and follow-up in routine disease management are mainly driven by OCT imaging. AI-based algorithms have by their precision, reproducibility and speed, the potential to reliably quantify biomarkers, predict disease progression and assist treatment decisions in clinical routine as well as academic studies. This review paper aims to provide a summary of the current state of AI in AMD, focusing on its applications, challenges, and prospects.

Diagnostic accuracy of community optometrists for age-related macular degeneration using colour fundus photographs: A pilot evaluation

PURPOSE

The accurate diagnosis of age-related macular degeneration (AMD) represents an important step in delaying and preventing vision loss and achieving optimal patient care. Therefore, this pilot study aimed to estimate the diagnostic accuracy of community optometrists for identifying AMD using colour fundus photographs (CFPs) to support sample size calculations for subsequent definitive studies.

METHODS

Five practising community optometrists were invited to classify a total of 1023 CFPs for the (1) presence of AMD, and, if applicable, (2) stage of AMD (early/intermediate/late geographic atrophy/late neovascular AMD). Diagnosis by referral centre clinicians formed the reference standard. Diagnostic accuracy was assessed by the area under the receiver operating characteristic curve (aROC). Sensitivity, specificity, positive and negative predictive values were also calculated.

RESULTS

Of the 1023 CFPs included in the study, 226 images were of AMD and 797 images were of other ocular conditions or no abnormal findings. Participating community optometrists had a mean (SD) age of 30.2 (8.9) years, 60.0% (3/5) were female and the mean number of years practising in primary eye care was 5.4 (5.4) years. Community optometrists demonstrated excellent performance for diagnosing AMD, with an aROC of 0.86 (95% CI 0.83 to 0.89), sensitivity of 84.5% (95% CI 79.1 to 89.0) and specificity of 88.0% (95% CI 85.5 to 90.1). The aROC (95% CI) for diagnosing early, intermediate, late geographic atrophy and late neovascular AMD was 0.82 (0.73 to 0.91), 0.76 (0.72 to 0.81), 0.69 (0.49 to 0.90) and 0.55 (0.34 to 0.75), respectively.

CONCLUSIONS

These results justify the need for an appropriately powered definitive study to assess community clinicians' diagnostic accuracy for AMD.

Targeted spectroscopy in the eye fundus

Significance

The assessment of biomarkers in the eye is rapidly gaining traction for the screening, diagnosis, and monitoring of ocular and neurological diseases. Targeted ocular spectroscopy is a technology that enables concurrent imaging of the eye fundus and analysis of high-quality spectra from a targeted region within the imaged area. This provides structural, compositional, and functional information of specific regions of the eye fundus from a non-invasive approach to ocular biomarker detection.

Aim

The aim of our study was to demonstrate the multimodal functionality and validation of targeted ocular spectroscopy. This was done in vitro, using a reference target and a model eye, and in vivo.

Approach

Images and spectra from different regions of a reference target and a model eye were acquired and analyzed to validate the system. Targeted ocular fluorescence spectroscopy was also demonstrated with the same model. Subsequently, in vivo imaging and diffuse reflectance spectra were acquired to assess blood oxygen saturation in the optic nerve head and the parafovea of healthy subjects.

Results

Tests conducted with the reference target showed accurate spectral analysis within specific areas of the imaging space. In the model eye, distinct spectral signatures were observed for the optic disc, blood vessels, the retina, and the macula, consistent with the variations in tissue composition and functions between these regions. An ocular oximetry algorithm was applied to in vivo spectra from the optic nerve head and parafovea of healthy patients, showing significant differences in blood oxygen saturation. Finally, targeted fluorescence spectral analysis was performed in vitro.

Conclusions

Diffuse reflectance and fluorescence spectroscopy in specific regions of the eye fundus open the door to a whole new range of monitoring and diagnostic capabilities, from assessment of oxygenation in glaucoma and diabetic retinopathy to photo-oxidation and photodegradation in age-related macular degeneration.

A deep learning model for generating fundus autofluorescence images from color fundus photography

Background

Fundus Autofluorescence (FAF) is a valuable imaging technique used to assess metabolic alterations in the retinal pigment epithelium (RPE) associated with various age-related and disease-related changes. The practical uses of FAF are ever-growing. This study aimed to evaluate the effectiveness of a generative deep learning (DL) model in translating color fundus (CF) images into synthetic FAF images and explore its potential for enhancing screening of age-related macular degeneration (AMD).

Methods

A generative adversarial network (GAN) model was trained on pairs of CF and FAF images to generate synthetic FAF images. The quality of synthesized FAF images was assessed objectively by common generation metrics. Additionally, the clinical effectiveness of the generated FAF images in AMD classification was evaluated by measuring the area under the curve (AUC), using the LabelMe dataset.

Results

A total of 8410 FAF images from 2586 patients were analyzed. The synthesized FAF images exhibited an impressive objectively assessed quality, achieving a multi-scale structural similarity index (MS-SSIM) of 0.67. When evaluated on the LabelMe dataset, the combination of generated FAF images and CF images resulted in a noteworthy improvement in AMD classification accuracy, with the AUC increasing from 0.931 to 0.968.

Conclusions

This study presents the first attempt to use a generative deep learning model to create authentic and high-quality FAF images from CF images. The incorporation of the translated FAF images on top of CF images improved the accuracy of AMD classification. Overall, this study presents a promising approach to enhance large-scale AMD screening.

Smart Contact Lenses as Wearable Ophthalmic Devices for Disease Monitoring and Health Management

The eye contains a complex network of physiological information and biomarkers for monitoring disease and managing health, and ocular devices can be used to effectively perform point-of-care diagnosis and disease management. This comprehensive review describes the target biomarkers and various diseases, including ophthalmic diseases, metabolic diseases, and neurological diseases, based on the physiological and anatomical background of the eye. This review also includes the recent technologies utilized in eye-wearable medical devices and the latest trends in wearable ophthalmic devices, specifically smart contact lenses for the purpose of disease management. After introducing other ocular devices such as the retinal prosthesis, we further discuss the current challenges and potential possibilities of smart contact lenses.

An Update on Multimodal Ophthalmological Imaging of Diffuse Choroidal Hemangioma in Sturge-Weber Syndrome

Sturge-Weber syndrome (SWS) is characterized by facial port-wine stains, leptomeningeal hemangiomas, and prominent ocular manifestations such as glaucoma and diffuse choroidal hemangiomas (DCHs). Imaging modalities are critical for diagnosing and longitudinally monitoring DCHs in SWS. Fundus photography is fundamental in assessing both eyes simultaneously, fluorescein angiography and indocyanine green angiography effectively map the retinal and choroidal circulation, and ultrasonography offers essential structural insights into the choroid and retina. NIR imaging reveals subtle retinal pigment changes, often overlooked in standard fundus examination. Enhanced depth imaging spectral domain optical coherence tomography (EDI-SDOCT) and swept-source OCT (SSOCT) improve the visualization of the choroidal-scleral boundary, essential for DCH characterization. The potential of OCT angiography (OCTA) is under exploration, particularly its role in predicting signs of disease progression or worsening, as well as potential new biomarkers such as the choroidal vascularity index (CVI). The present review aims to provide an update on multimodal imaging of DCHs in SWS.

Quantitative Fundus Autofluorescence in Systemic Chloroquine/Hydroxychloroquine Therapy: One Year Follow-Up

Purpose

Systemic chloroquine/hydroxychloroquine (CQ/HCQ) can cause severe ocular side effects including bull's eye maculopathy (BEM). Recently, we reported higher quantitative autofluorescence (QAF) levels in patients with CQ/HCQ intake. Here, QAF in patients taking CQ/HCQ in a 1-year follow-up is reported.

Methods

Fifty-eight patients currently or previously treated with CQ/HCQ (cumulative doses 94-2435 g) and 32 age- and sex-matched healthy subjects underwent multimodal retinal imaging (infrared, red free, fundus autofluorescence [FAF], QAF [488 nm], and spectral-domain optical coherence tomography (SD-OCT). For analysis, custom written FIJI plugins were used for image processing, multimodal image stacks assembling, and QAF calculation.

Results

Thirty patients (28 without BEM and 2 with BEM, age range = 25-69 years) were followed up (370 ± 63 days). QAF values in patients taking CQ/HCQ showed a significant increase between baseline and follow-up examination: 282.0 ± 67.9 to 297.7 ± 70.0 (QAF a.u.), P = 0.002. An increase up to 10% was observed in the superior macular hemisphere. Eight individuals (including 1 patient with BEM) had a pronounced QAF increase of up to 25%. Compared to healthy controls, QAF levels in patients taking CQ/HCQ were significantly increased (P = 0.04).

Conclusions

Our study confirms our previous finding of increased QAF in patients taking CQ/HCQ with a further significant QAF increase from baseline to follow-up. Whether pronounced QAF increase might predispose for rapid progression toward structural changes and BEM development is currently investigated in ongoing studies.

Translational Relevance

In addition to standard screening tools during systemic CQ/HCQ treatment, QAF imaging might be useful in CQ/HCQ monitoring and could serve as a screening tool in the future.

Nutrition-induced macular-degeneration-like photoreceptor damage in jumping spider eyes

Age-related macular degeneration (AMD) is a leading cause of vision loss in humans. Despite its prevalence and medical significance, many aspects of AMD remain elusive and treatment options are limited. Here, we present data that suggest jumping spiders offer a unique opportunity for understanding the fundamentals underlying retinal degeneration, thereby shedding light on a process that impacts millions of people globally. Using a micro-ophthalmoscope and histological evidence, we demonstrate that significant photoreceptor damage can occur during development in the image-forming anterior lateral eyes of the jumping spider Phidippus audax. Furthermore, we find that this photoreceptor degeneration is exacerbated by inadequate nutrition and is most prevalent in the high-density region of the retina, like AMD in humans. This suggests that similar to those in vertebrates, the retinas in P. audax are challenged to meet high-energy cellular demands.

Prolonged Lifetimes of Histologic Autofluorescence in Ectopic Retinal Pigment Epithelium in Age-Related Macular Degeneration

Purpose

The purpose of this study was to investigate histologic autofluorescence lifetimes and spectra of retinal pigment epithelium (RPE) on the transition from normal aging to RPE activation and migration in age-related macular degeneration (AMD).

Methods

Autofluorescence lifetimes and spectra of 9 donor eyes were analyzed in cryosections by means of 2-photon excited fluorescence at 960 nm. Spectra were detected at 483 to 665 nm. Lifetimes were measured using time-correlated single photon counting in 2 spectral channels: 500 to 550 nm (short-wavelength spectral channel [SSC]) and 550 to 700 nm (long-wavelength spectral channel [LSC]). Fluorescence decays over time were approximated by a series of three exponential functions. The amplitude-weighted mean fluorescence lifetime was determined. Markers for retinoid activity (RPE65) and immune function (CD68) were immunolocalized in selected neighboring sections.

Results

We identified 9 RPE morphology phenotypes resulting in 399 regions of interest (ROIs) for spectral and 497 ROIs for lifetime measurements. RPE dysmorphia results in a shorter wavelength peak of spectral emission: normal aging versus RPE migrated into the retina (intraELM) = 601.7 (9.5) nm versus 581.6 (7.3) nm, P < 0.001, whereas autofluorescence lifetimes increase: normal aging versus intraELM: SSC 180 (44) picosecond (ps) versus 320 (86) ps, P < 0.001; and LSC 250 (55) ps versus 441 (76) ps, P < 0.001. Ectopic RPE within the neurosensory retina is strongly CD68 positive and RPE65 negative.

Conclusions

In the process of RPE degeneration, comprising different steps of dysmorphia and migration, lengthening of autofluorescence lifetimes and a hypsochromic shift of emission spectra can be observed. These autofluorescence changes might provide early biomarkers for AMD progression and contribute to our understanding of RPE-driven pathology.

Macular Atrophy Incidence, Progression, and Visual Acuity Effects in 5-Year Treatment of Neovascular Age-Related Macular Degeneration

BACKGROUND AND OBJECTIVE

Macular atrophy (MA) contributes to declining vision during prolonged anti-vascular endothelial growth factor (VEGF) treatment in neovascular age-related macular degeneration (nAMD) so greater understanding of its incidence, evolution, and impact on visual acuity is merited.

MATERIALS AND METHODS

This is a retrospective review of nAMD patients receiving anti-VEGF therapy for ≥ 5 years. Near-infrared reflectance images and vision data were extracted every 6 months. MA lesion areas were measured using ImageJ.

RESULTS

Vision showed a mean decline of -1.2 letters/year. Eyes with MA showed a greater decrease of -1.6 letters/year compared to eyes without MA (-0.7 letters/year). Cumulative incidence of MA was 38% at 5 years. MA was significantly associated with declining vision, showing a -0.7 letter decrease for every 1 mm² increase in lesion size.

CONCLUSION

Over a 5-year course of nAMD treatment, MA affected most eyes, and MA progression was significantly associated with vision decline. [Ophthalmic Surg Lasers Imaging Retina 2022;53:546-552.].

The Role of Medical Image Modalities and AI in the Early Detection, Diagnosis and Grading of Retinal Diseases: A Survey

Traditional dilated ophthalmoscopy can reveal diseases, such as age-related macular degeneration (AMD), diabetic retinopathy (DR), diabetic macular edema (DME), retinal tear, epiretinal membrane, macular hole, retinal detachment, retinitis pigmentosa, retinal vein occlusion (RVO), and retinal artery occlusion (RAO). Among these diseases, AMD and DR are the major causes of progressive vision loss, while the latter is recognized as a world-wide epidemic. Advances in retinal imaging have improved the diagnosis and management of DR and AMD. In this review article, we focus on the variable imaging modalities for accurate diagnosis, early detection, and staging of both AMD and DR. In addition, the role of artificial intelligence (AI) in providing automated detection, diagnosis, and staging of these diseases will be surveyed. Furthermore, current works are summarized and discussed. Finally, projected future trends are outlined. The work done on this survey indicates the effective role of AI in the early detection, diagnosis, and staging of DR and/or AMD. In the future, more AI solutions will be presented that hold promise for clinical applications.

Imaging of Uveal Melanoma—Current Standard and Methods in Development

Simple Summary

Uveal melanoma is the most prevalent intraocular tumor in adults, derived from melanocytes; the liver is the most common site of its metastases. Due to troublesome tumor localization, different imaging techniques are utilized in diagnostics, i.e., fundus imaging (FI), ultrasonography (US), optical coherence tomography (OCT), single-photon emission computed tomography (SPECT), positron emission tomography/computed tomography (PET/CT), magnetic resonance imaging (MRI), fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA), or fundus autofluorescence (FAF). Specialists eagerly use these techniques, but sometimes the precision and quality of the obtained images are imperfect, raising diagnostic doubts and prompting the search for new ones. In addition to analyzing the currently utilized methods, this review also introduces experimental techniques that may be adapted to clinical practice in the future. Moreover, we raise the topic and present a perspective for personalized medicine in uveal melanoma treatment.

Abstract

Uveal melanoma is the most common primary intraocular malignancy in adults, characterized by an insidious onset and poor prognosis strongly associated with tumor size and the presence of distant metastases, most commonly in the liver. Contrary to most tumor identification, a biopsy followed by a pathological exam is used only in certain cases. Therefore, an early and noninvasive diagnosis is essential to enhance patients’ chances for early treatment. We reviewed imaging modalities currently used in the diagnostics of uveal melanoma, including fundus imaging, ultrasonography (US), optical coherence tomography (OCT), single-photon emission computed tomography (SPECT), fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA), fundus autofluorescence (FAF), as well as positron emission tomography/computed tomography (PET/CT) or magnetic resonance imaging (MRI). The principle of imaging techniques is briefly explained, along with their role in the diagnostic process and a summary of their advantages and limitations. Further, the experimental data and the advancements in imaging modalities are explained. We describe UM imaging innovations, show their current usage and development, and explain the possibilities of utilizing such modalities to diagnose uveal melanoma in the future.

Multispectral pattern recognition measures change in drusen area in age-related macular degeneration with high congruency to expert graders

Drusen are a hallmark lesion of age-related macular degeneration (AMD) and changes in their area and/or volume are strongly associated with disease progression. Assessment of longitudinal change in drusen size in clinical practice however is limited to a single commercial tool or manual inspection by clinicians. In this study we analysed change in drusen area in 33 eyes with intermediate AMD across two separate visits using a novel technique known as multispectral pattern recognition for en face retinal images from various imaging modalities (infrared (815 nm), fundus autofluorescence (488 nm) and green (532 nm) scanning laser ophthalmoscopy). We found 91% (30/33 eyes) agreement in the direction of drusen change for multispectral pattern recognition relative to expert graders who graded eyes as having drusen progression, regression or being stable. Multispectral pattern recognition showed 100% sensitivity (22/22 eyes) and 73% specificity (8/11 eyes). In comparison, we found only 70% (23/33 eyes) agreement in the direction of drusen change with a commercially available change analysis software, the Cirrus Advanced RPE Analysis relative to expert graders, with a sensitivity 64% (14/22 eyes) and specificity of 82% (9/11 eyes). Total drusen area or amount of change between visits had no significant effect on agreement. This suggests multispectral pattern recognition can quantify longitudinal change in drusen area from multimodal imaging with greater congruency to expert graders than a commercially available platform based on a single imaging modality. Considering the association of drusen area and disease progression, this method could aid clinical assessment and monitoring of AMD.

Skin's green autofluorescence at dorsal centremetacarpus may become a novel biomarker for diagnosis of lung cancer

It is critical to discover novel biomarkers of lung cancer for establishing economical technology for diagnosis of lung cancer. Our study has suggested that the autofluorescence (AF) of the skin may become a novel biomarker of this type: First, development of lung cancer led to a significant increase in the skin's green AF in a mouse model of lung cancer; second, lung cancer patients had significantly higher skin's green AF at certain positions compared with healthy volunteers and pulmonary infection patients; and third, using the skin's green AF intensity at dorsal centremetacarpus as the variable, the areas under curve (AUC) for differentiating lung cancer patients and pulmonary infection patients and for differentiating lung cancer patients and healthy volunteers was 0.871 and 0.813, respectively. Collectively, our study has indicated that the skin's green AF at dorsal centremetacarpus may become a novel biomarker for establishing a ground-breaking diagnostic strategy for lung cancer.

Evolving Patterns of Hyperfluorescent Fundus Autofluorescence Accompany Retinal Atrophy in the Rat and Mimic Atrophic Age-Related Macular Degeneration

Purpose

Complex two-dimensional (2D) patterns of hyperfluorescent short-wave fundus autofluorescence (FAF) at the border of geographic atrophy (GA) can predict its expansion in patients with late non-exudative “dry” AMD. However, preclinical models do not phenocopy this important feature of disease. We sought to describe the spatiotemporal changes in hyperfluorescent FAF patterns that occur following acute oxidative stress, potentially in association with GA expansion.

Methods

Sprague Dawley rats (n = 54) received systemic sodium iodate (25–45 mg/kg, n = 90 eyes) or saline (n = 18 eyes) and underwent serial full fundus imaging by confocal scanning laser ophthalmoscopy, including blue FAF and delayed near-infrared analysis. Composite images of the fundus were assembled, and the 2D patterns were described qualitatively and quantitatively. A subset of eyes underwent tissue analysis, and four underwent optical coherence tomography (OCT) imaging.

Results

Reproducibly changing, complex patterns of hyperfluorescent FAF emerge at the borders of toxin-induced damage; however, in the absence of GA expansion, they percolate inward within the region of retinal pigment epithelium loss, evolving, maturing, and senescing in situ over time. Unexpectedly, the late FAF patterns most closely resemble the diffuse tricking form of clinical disease. A five-stage classification system is presented.

Conclusions

Longitudinal, full-fundus imaging of outer retinal atrophy in the rat eye identifies evolving, complex patterns of hyperfluorescent FAF that phenocopy aspects of disease.

Translational Relevance

This work provides a novel tool to assess hyperfluorescent FAF in association with progressive retinal atrophy, a therapeutic target in late AMD.

Exudative versus Nonexudative Age-Related Macular Degeneration: Physiopathology and Treatment Options

Age-related macular degeneration (AMD) is an eye disease typically associated with the aging and can be classified into two types—namely, the exudative and the nonexudative AMD. Currently available treatments for exudative AMD use intravitreal injections, which are associated with high risk of infection that can lead to endophthalmitis, while no successful treatments yet exist for the nonexudative form of AMD. In addition to the pharmacologic therapies administered by intravitreal injection already approved by the Food and Drug Administration (FDA) in exudative AMD, there are some laser treatments approved that can be used in combination with the pharmacological therapies. In this review, we discuss the latest developments of treatment options for AMD. Relevant literature available from 1993 was used, which included original articles and reviews available in PubMed database and also information collected from Clinical Trials Gov website using “age-related macular degeneration” and “antiangiogenic therapies” as keywords. The clinical trials search was limited to ongoing trials from 2015 to date.

Association of Near-Infrared and Short-Wavelength Autofluorescence With the Retinal Sensitivity in Eyes With Resolved Central Serous Chorioretinopathy

Purpose

The purpose of this study was to compare the results of near-infrared autofluorescence (NIRAF) and short-wavelength autofluorescence (SWAF) imaging of eyes with resolved central serous chorioretinopathy (CSC) and to assess the retinal sensitivity (RS) in areas with abnormal autofluorescence (AF) using white-on-white (WW) and blue-on-yellow (BY) perimetries.

Methods

We examined 20 consecutive eyes with resolved CSC. We calculated the areas of abnormal AF detected by SWAF and NIRAF imaging as SWAF_area and NIRAF_area, respectively, and the number of measurement points within and outside abnormal SWAF and NIRAF regions were counted. The results of WW and BY perimetries were superimposed on the AF images, and the mean overall RS within and outside abnormal SWAF and NIRAF regions were calculated using both WW and BY perimetries (W-RSin_SWAF, W-RSout_SWAF, W-RSin_NIRAF, W-RSout_NIRAF, B-RSin_SWAF, B-RSout_SWAF, B-RSin_NIRAF, and B-RSout_NIRAF, respectively).

Results

The mean age of the participants was 54.1 years. The SWAF_area was significantly smaller than the NIRAF_area (P < 0.0001, Wilcoxon signed rank test). A χ2 test suggested a significant relationship between the number of measurement points within/outside abnormal SWAF and NIRAF regions (P < 0.0001). In the results of measurement by WW perimetry, there was a significant difference between W-RSin_NIRAF and W-RSout_NIRAF (P < 0.0001), but not between W-RSin_SWAF and W-RSout_SWAF (P = 0.060, Wilcoxon rank sum test). In contrast, on BY perimetry, there were significant differences between both B-RSin_SWAF and B-RSout_SWAF and between B-RSin_NIRAF and B-RSout_NIRAF (P < 0.0001).

Conclusions

NIRAF was useful for predicting impaired RS in eyes with resolved CSC.

RECLASSIFICATION OF FUNDUS AUTOFLUORESCENCE PATTERNS SURROUNDING GEOGRAPHIC ATROPHY BASED ON PROGRESSION RATE: A Systematic Review and Meta-Analysis

PURPOSE

To reclassify fundus autofluorescence (FAF) patterns around geographic atrophy (GA) based on GA progression rates.

METHODS

MEDLINE, EMBASE, Cochrane Library, Clinicaltrials.gov, and PubMed were searched for studies reporting GA progression rates among different FAF patterns, such as "None," "Focal," "Banded," "Patchy," "Diffuse Nontrickling," and "Diffuse Trickling." The GA radius growth rate among different FAF patterns was compared, and a GA growth function for each group was derived. To account for the patients' different entry times, a horizontal translation factor was introduced to shift each data subset from "time after enrollment" to "duration of GA."

RESULTS

Seven studies with 496 eyes were included. Based on GA radius growth rates, the six FAF patterns were clustered into four groups with a high correlation coefficient within each group: Group 1, None, 0.061 mm/year (r = 0.996), Group 2, Focal, 0.105 mm/year (r = 0.987), Group 3, Banded, Patchy, and Diffuse Nontrickling, 0.149 mm/year (r = 0.993), and Group 4, "Diffuse Trickling, 0.245 mm/year (r = 0.997).

CONCLUSION

This meta-analysis suggested that the six FAF patterns can be coalesced into four groups based on lesion progression rates. Simplification of the reclassified FAF patterns may shed light on the GA natural history and assist in the design of clinical trials.

Recent Developments in the Treatment of Wet Age-related Macular Degeneration

Age-related macular degeneration (AMD) is the most common cause of irreversible blindness and visual impairment in individuals over the age of 50 years in western societies. More than 25 million people currently suffer from this illness in the world, with an additional 500 000 every year, approximately. It is a multifactorial ocular disease that affects the maculae due to a late-onset progressive neurodegeneration and dysfunction of photoreceptors and retinal pigment epithelium (RPE). There are many subtypes of AMD but basically two broad forms: the nonneovascular (dry, nonexudative) and neovascular (wet, exudative). Exudative AMD is the less common form (about 15%) but tends to progress more rapidly. At the moment, wet AMD is treated primarily on the basis of anti-vascular endothelial growth factor (VEGF) agents, which have led to massive improvement in the prognosis of the disease since they were first introduced. This article focuses on the latest treatment approaches to neovascular AMD. An extensive literature review was performed in order to illustrate the effectiveness of current and future anti-VEGF agents as well as the landmark clinical studies that have been carried out to establish these drugs as a gold standard in the therapy of wet AMD.

Early Detection of Incipient Retinal Pigment Epithelium Atrophy Overlying Drusen with Fundus Autofluorescence vs. Spectral Domain Optical Coherence Tomography

Purpose

This study aims to find out which tool, fundus autofluorescence (FAF) or spectral domain optical coherence tomography (SD-OCT), is more sensitive in detecting retinal pigment epithelium (RPE) demise overlying drusen and can, therefore, help predict geographic atrophy (GA) appearance in Age-Related Macular Degeneration (AMD).

Methods

A single-site, retrospective, observational, longitudinal study was conducted. Patients with intermediate AMD (iAMD) (large (>125 μm) or intermediate (63–125 μm) drusen with hyper/hypopigmentation) with a minimum follow-up of 18 months were included. Drusen with overlying incipient RPE atrophy were identified on SD-OCT defined as choroidal hypertransmission or nascent geographic atrophy (nGA). These selected drusen were, then, traced backwards in time to determine if incipient RPE atrophy overlying drusen was observed on FAF (well-demarcated region of absence of autofluorescence) before, simultaneously, or after having detected the first signs of incipient RPE atrophy on SD-OCT. The number of drusen in which signs of incipient RPE atrophy was detected earlier using FAF or SD-OCT was compared. The time elapsed from the identification with the more sensitive method to the other was recorded and analyzed.

Results

One hundred and thirty-three drusen in 22 eyes of 22 patients were included. Of these, 112 (84.2%) drusen showed choroidal hypertransmission and 21(15.8%) nGA. Early signs of atrophy overlying drusen were found simultaneously on SD-OCT and FAF in 52 cases (39.1%, 95% CI 30.8–47.9%), earliest on FAF in 51 (38.3%, 95% CI 30.0–47.2%) and first on SD-OCT in 30 (22.6%, 95% CI 15.8–30.6%; p < 0.05). Statistically significant differences were found between both techniques (p=0.005), with FAF detecting it earlier than SD-OCT. When RPE atrophy was found first on FAF, the median time to diagnosis with SD-OCT was 6.6 months (95% CI 5.5 to 8.6), while if detection occurred earlier on SD-OCT, the median time until identification with FAF was 12.6 months (95% CI 6.0 to 23.4; p=0.0003).

Conclusions

In iAMD cases in which early atrophy overlying drusen is not detected simultaneously in FAF and SD-OCT, FAF was significantly more sensitive. Nevertheless, a multimodal approach is recommended and required to evaluate these patients.

Recent Advances and the Potential for Clinical Use of Autofluorescence Detection of Extra-Ophthalmic Tissues

The autofluorescence (AF) characteristics of endogenous fluorophores allow the label-free assessment and visualization of cells and tissues of the human body. While AF imaging (AFI) is well-established in ophthalmology, its clinical applications are steadily expanding to other disciplines. This review summarizes clinical advances of AF techniques published during the past decade. A systematic search of the MEDLINE database and Cochrane Library databases was performed to identify clinical AF studies in extra-ophthalmic tissues. In total, 1097 articles were identified, of which 113 from internal medicine, surgery, oral medicine, and dermatology were reviewed. While comparable technological standards exist in diabetology and cardiology, in all other disciplines, comparability between studies is limited due to the number of differing AF techniques and non-standardized imaging and data analysis. Clear evidence was found for skin AF as a surrogate for blood glucose homeostasis or cardiovascular risk grading. In thyroid surgery, foremost, less experienced surgeons may benefit from the AF-guided intraoperative separation of parathyroid from thyroid tissue. There is a growing interest in AF techniques in clinical disciplines, and promising advances have been made during the past decade. However, further research and development are mandatory to overcome the existing limitations and to maximize the clinical benefits.

Tracing the retina to analyze the integrity and phagocytic capacity of the retinal pigment epithelium

We have developed a new technique to study the integrity, morphology and functionality of the retinal neurons and the retinal pigment epithelium (RPE). Young and old control albino (Sprague-Dawley) and pigmented (Piebald Virol Glaxo) rats, and dystrophic albino (P23H-1) and pigmented (Royal College of Surgeons) rats received a single intravitreal injection of 3% Fluorogold (FG) and their retinas were analyzed from 5 minutes to 30 days later. Retinas were imaged in vivo with SD-OCT and ex vivo in flat-mounts and in cross-sections. Fifteen minutes and 24 hours after intravitreal administration of FG retinal neurons and the RPE, but no glial cells, were labeled with FG-filled vesicles. The tracer reached the RPE 15 minutes after FG administration, and this labeling remained up to 30 days. Tracing for 15 minutes or 24 hours did not cause oxidative stress. Intraretinal tracing delineated the pathological retinal remodelling occurring in the dystrophic strains. The RPE of the P23H-1 strain was highly altered in aged animals, while the RPE of the RCS strain, which is unable to phagocytose, did not accumulate the tracer even at young ages when the retinal neural circuit is still preserved. In both dystrophic strains, the RPE cells were pleomorphic and polymegathic.

Risk factors for progression of age-related macular degeneration

Purpose

Age‐related macular degeneration (AMD) is a degenerative disease of the macula, often leading to progressive vision loss. The rate of disease progression can vary among individuals and has been associated with multiple risk factors. In this review, we provide an overview of the current literature investigating phenotypic, demographic, environmental, genetic, and molecular risk factors, and propose the most consistently identified risk factors for disease progression in AMD based on these studies. Finally, we describe the potential use of these risk factors for personalised healthcare.

Recent findings

While phenotypic risk factors such as drusen and pigment abnormalities become more important to predict disease progression during the course of the disease, demographic, environmental, genetic and molecular risk factors are more valuable at earlier disease stages. Demographic and environmental risk factors such as age and smoking are consistently reported to be related to disease progression, while other factors such as sex, body mass index (BMI) and education are less often associated. Of all known AMD variants, variants that are most consistently reported with disease progression are rs10922109 and rs570618 in CFH, rs116503776 in C2/CFB/SKIV2L, rs3750846 in ARMS2/HTRA1 and rs2230199 in C3. However, it seems likely that other AMD variants also contribute to disease progression but to a lesser extent. Rare variants have probably a large effect on disease progression in highly affected families. Furthermore, current prediction models do not include molecular risk factors, while these factors can be measured accurately in the blood. Possible promising molecular risk factors are High‐Density Lipoprotein Cholesterol (HDL‐C), Docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), zeaxanthin and lutein.

Summary

Phenotypic, demographic, environmental, genetic and molecular risk factors can be combined in prediction models to predict disease progression, but the selection of the proper risk factors for personalised risk prediction will differ among individuals and is dependent on their current disease stage. Future prediction models should include a wider set of genetic variants to determine the genetic risk more accurately, and rare variants should be taken into account in highly affected families. In addition, adding molecular factors in prediction models may lead to preventive strategies and personalised advice.

Blue-Light Fundus Autofluorescence Imaging following Ruthenium-106 Brachytherapy for Choroidal Melanoma

PURPOSE

To describe changes in blue-light fundus autofluorescence (FAF) and corresponding alterations in optical coherence tomography (OCT) within the irradiation field after ruthenium-106 brachytherapy (RBT) for choroidal melanoma.

METHODS

Consecutive patients with choroidal melanoma were included in a retrospective case series. Patients were treated with RBT at a single institution. As part of their routine examination patients underwent multimodal imaging including ultrasonography, fundus photography, OCT, and FAF imaging (excitation = 488 nm). FAF images were analysed for changes within the irradiation field.

RESULTS

31 patients (mean age 65.7 years) were treated with RBT for unilateral choroidal melanoma. Mean tumour height before therapy was 2.7 mm (SD 1.0). Mean follow-up time was 23.3 months (SD 13.3). Main FAF characteristics attributable to RBT emerged as increased FAF with speckled decreased FAF (FAF mottling) within the irradiation field and a rim of increased FAF at its border. OCT scans demonstrated loss of the ellipsoid zone and the external limiting membrane, thinning of the neurosensory retina, and alterations of the retinal pigment epithelium like clumping, migration, and atrophy.

CONCLUSIONS

FAF changes in the irradiation field after RBT of choroidal melanomas follow a characteristic pattern that correlates with distinct OCT alterations. FAF and OCT imaging give additional information to monitor effects of RBT and, therefore, complement multimodal imaging techniques after plaque therapy.

Burden of Illness in Geographic Atrophy: A Study of Vision-Related Quality of Life and Health Care Resource Use

Purpose

To gain comprehensive information on the burden of illness due to geographic atrophy (GA).

Methods

This cross-sectional study with a retrospective chart review involved patients aged ≥70 years with physician-confirmed bilateral symptomatic GA due to age-related macular degeneration (GA group), as well as patients of similar age with no ophthalmic condition that in the opinion of the investigator affected visual function (non-GA group). Data relating to patients’ current disease status and sociodemographics were self-reported on patient questionnaires at study entry and extracted from patient charts. Historical data on health care resource utilization (HCRU) were also collected via patient questionnaires and retrospective chart review (GA group only). Overall vision-related functioning and quality of life (QoL) were compared between the GA and non-GA groups using the National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25) composite and subscales, and change in vision over the past year was assessed using the Global Rating of Change Scale.

Results

Vision-related functioning and QoL were poorer in patients with vs without GA (n=137 vs 52), as demonstrated by significantly lower NEI-VFQ-25 composite score (mean, 53.1 vs 84.5 points, respectively; P<0.001), as well as lower subscale scores for near activities, distance activities, dependency, driving, social functioning, mental health, role difficulties, color vision, and peripheral vision. Substantially more patients with GA than without GA reported worsening in vision over the past year (82% vs 25%, respectively; odds ratio, 13.55; P<0.001). In the GA group, associated mean annual costs for direct ophthalmological resource use per patient amounted to €1772 (mostly for tests/procedures), and for indirect ophthalmological resource use, €410 (mostly for general practitioner visits).

Conclusion

Patients with GA experience a poorer level of vision-related function and QoL than their peers, especially in relation to driving. GA is also associated with notable HCRU/associated costs, mostly direct costs attributed to diagnostic tests/procedures.

Optometry Australia's chairside reference for the diagnosis and management of age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss in people over the age of 50 years in Australia. Optometry Australia has developed this AMD chairside reference in consultation with a member-based working group comprised of experienced practitioners. It provides an evidence-based approach to current best practice in the diagnosis and management of AMD. Optometrists should be competent in assessing patients with or at risk of developing AMD, so that they are able to provide evidence-based management including appropriate communication, diagnosis and referral when indicated. This AMD chairside reference covers risk factors for the development of AMD or progression to late-stage AMD; the current clinical classification of AMD; common signs and symptoms; optometric assessment including ocular imaging and biomarkers; differential diagnoses; and management of early, intermediate and late AMD. Optometry Australia's chairside reference is intended as a general guide for optometrists, and is not a formal management protocol.

Blue Autofluorescence Fundus Imaging for Monitoring Retinal Degeneration in Royal College of Surgeons Rats

Purpose

Development of a method for noninvasive longitudinal follow-up of retinal degeneration in the whole retina for Royal College of Surgeons (RCS) rats, a commonly used model of retinitis pigmentosa associated with mutations in the MER-proto-oncogene tyrosine kinase (MERTK) gene.

Methods

Pigmented RCS rats at postnatal (p) days p28 to p84 were subjected to a biweekly spectral-domain optical coherence tomography (SD-OCT), blue laser fundus autofluorescence (BL-FAF) imaging, and multicolor fundus imaging. Wild-type (WT; Long Evans) rats were tested as control.

Results

Hyperautofluorescence developed throughout the fundus at p42, concomitant with a significant increase in SD-OCT thickness and reflectivity of the debris zone (DZ) layer as well as thinning of the photoreceptor outer nuclear layer (ONL). From p56 to p84, discrete hypofluorescent lesions surrounded by hyperfluorescent flecks were demonstrated around the optic disc that gradually spread throughout the retina. The hypofluorescent lesions were associated with loss of ONL and gradual thinning of the DZ layer. No hypofluorescent BL-FAF lesions were observed in WT rats.

Conclusions

This study suggests that BL-FAF imaging may present a new method for noninvasive longitudinal follow-up of retinal degeneration in nearly the whole retina in RCS rats.

Translational Relevance

A clinical test was developed that may be implemented in translational studies in the RCS rat model of MERTK-associated retinitis pigmentosa.

Developing prognostic biomarkers in intermediate age-related macular degeneration: their clinical use in predicting progression

Age-related macular degeneration is a common, complex and blinding eye disease. When early and intermediate levels of severity are detected in one or both eyes, there is a wide-ranging 0.4 to 53 per cent risk of progression to advanced disease in five years. In order to maximise visual outcomes for their patients, practising eye-care professionals must be able to stratify patients according to their risk of progression, intervene (for example by recommending smoking cessation or nutritional supplements and Amsler grid self-monitoring in intermediate disease) and monitor accordingly. With the aid of ocular imaging, a range of under-recognised yet meaningful risk factors have been identified. The purpose of this review is to assist the eye-care practitioner in stratifying the risk of progression in intermediate age-related macular degeneration using the range of established and emerging precursory signs that herald loss of vision.

Automated drusen detection in dry age-related macular degeneration by multiple-depth, en face optical coherence tomography

We introduce a method to automatically detect drusen in dry age-related macular degeneration (AMD) from optical coherence tomography with minimum need for layer segmentation. The method is based on the en face detection of drusen areas in C-scans at certain distances above the Bruch's membrane, circumventing the difficult task of pathologic retinal pigment epithelium segmentation. All types of drusen can be detected, including the challenging subretinal drusenoid deposits (pseudodrusen). The high sensitivity and accuracy demonstrated here shows its potential for detection of drusen onset in early AMD.

Advanced imaging for the diagnosis of age-related macular degeneration: a case vignettes study

Background

The aim of this study is to evaluate the diagnosis, staging, imaging and management preferences, and the effect of advanced imaging among practising optometrists in age‐related macular degeneration (AMD).

Methods

Up to 20 case vignettes (computer‐based case simulations) were completed online in a computer laboratory in random order by 81 practising optometrists of Australia. Each case presented findings from a randomly selected patient seen previously at the Centre for Eye Health for a macular assessment in the following order: case history, preliminary tests and colour fundus photography. Participants were prompted to provide their diagnosis, management and imaging preference. One additional imaging result (either modified fundus photographs and infrared images, fundus autofluorescence, or optical coherence tomography [OCT]) was then provided and the questions repeated. Finally, all imaging results were provided and the questions repeated a third time.

Results

A total of 1,436 responses were analysed. The presence of macular pathology in AMD was accurately detected in 94 per cent of instances. The overall diagnostic accuracy of AMD was 61 per cent using colour fundus photography. This improved by one per cent using one additional imaging modality and a further four per cent using all imaging. Across all responses, a greater improvement in the diagnostic accuracy of AMD occurred following the presentation of OCT findings (versus other modalities). OCT was the most preferred imaging modality for AMD, while multimodal imaging was of greatest benefit in cases more often misdiagnosed using colour fundus photography alone. Overall, the cohort also displayed a tendency to underestimate disease severity.

Conclusion

Despite reports that imaging technologies improve the stratification of AMD, our findings suggest that this effect may be small when applied among practising optometrists without additional or specific training.

MORPHOLOGIC FEATURES ASSOCIATED WITH FIBROTIC SCARRING AFTER ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY IN POLYPOIDAL CHOROIDAL VASCULOPATHY

PURPOSE

To investigate morphologic features associated with fibrotic scarring after anti-vascular endothelial growth factor therapy in polypoidal choroidal vasculopathy (PCV).

METHODS

This retrospective study included 293 patients who had been diagnosed with PCV and treated with anti-vascular endothelial growth factor monotherapy during a 12-month follow-up period. Associations of morphologic features, including type of PCV, location of the polypoidal lesion, greatest linear dimension, largest polyp diameter, choroidal vascular hyperpermeability, pigment epithelial detachment, intraretinal fluid, and subretinal hyperreflective material (SHRM) with fibrotic scar at 12 months were analyzed.

RESULTS

Fibrotic scars were noted in 15 eyes (5.1%). The incidence of fibrotic scars was higher in Type 1 PCV (8 of 76 eyes) than in Type 2 PCV (7 of 217 eyes, P = 0.028). The incidence was also higher in eyes with SHRM (14 of 124 eyes) than in eyes without SHRM (1 of 169 eyes, P < 0.001). In multivariate analysis, SHRM was associated with fibrotic scar (P = 0.005). Among the SHRM cases, the incidence of the scar was 12.9% in eyes with submacular hemorrhage and 8.5% in eyes without hemorrhage.

CONCLUSION

Although fibrotic scar is an infrequent finding in PCV, the possibility of scarring should be considered in eyes with SHRM, particularly in submacular hemorrhage cases.