QUANTITATIVE AUTOFLUORESCENCE IN CENTRAL SEROUS CHORIORETINOPATHY

BACKGROUND/PURPOSE

Central serous chorioretinopathy (CSC) is associated with pachychoroid and dysfunctional retinal pigment epithelium. Autofluorescence (AF) is typically altered. The authors performed this study to quantify these alterations using quantitative AF (qAF) in patients with CSC and in their fellow eye in comparison with a healthy control group.

METHODS

Patients with CSC and healthy controls were recruited prospectively. All patients received a full clinical examination including best-corrected visual acuity, enhanced depth imaging-optical coherence tomography, and qAF. Quantitative autofluorescence images were taken with a confocal scanning laser ophthalmoscope (Heidelberg Engineering). Quantitative autofluorescence values were assessed in specified regions of the inner eight and the middle ring of the Delori grid.

RESULTS

In total, 141 eyes of 77 patients with CSC were included. Ninety eyes had a manifest CSC (group 1) while 51 fellow eyes (group 2) did not show signs of CSC. There were no significant differences of qAF values between these two groups: mean qAF values were 241.3 (inner eight) and 212.8 (middle ring) in group 1 and 235.9 (inner eight) and 210.0 (middle ring) in group 2 ( P = 1.0 and 1.0). We compared these eyes with healthy controls comprising 39 eyes. Quantitative autofluorescence signals (inner eight: 164.7; middle ring: 148.9) differed significantly compared with both CSC manifest ( P < 0.001) and fellow eyes ( P < 0.001).

CONCLUSION

Our results show that patients with CSC have increased qAF values in both eyes with manifest CSC and asymptomatic, clinically unremarkable fellow eyes in comparison with healthy controls. This finding suggests that qAF alterations are present even before clinical signs can be observed.

Comparability of input parameters in the German Retina.net ROP registry and the EU-ROP registry - An exemplary comparison between 2011 and 2021

PURPOSE

The German Retina.net ROP registry and its Europe-wide successor, the EU-ROP registry, collect data from patients treated for ROP. This analysis compares input parameters of these two registries to establish a procedure for joint analyses of different registry data using exemplary datasets from the two registries.

METHODS

Exemplary datasets from the two databases over a 1-year period each (German Retina.net ROP Registry, 2011, 22 infants; EU-ROP Registry, 2021, 44 infants) were compared. The parameters documented in the two databases were aligned and analysed regarding demographic parameters, treatment modalities, complications within first 24 h and retreatments.

RESULTS

The current analysis showed that data can be aligned for joint analyses with some adjustments within the data structure. The registry with more detailed data collection (EU-ROP) needs to be reduced regarding granularity in order to align the different registries, as the registry with lower granularity determines the level of analyses that can be performed in a comparative approach. In the exemplary datasets, we observed that the overall most common ROP severity in both registries was zone II, 3+ (2011: 70.5%; 2021: 65%), with decreasing numbers of clock hours showing preretinal neovascularisations (2011: 10-12 clock hours in 29% of cases, 2021: 4-6 clock hours in 38%). The most prevalent treatment method was laser coagulation in 2011 (75%) and anti-VEGF therapy in 2021 (86.1%). Within the anti-VEGF group, all patients were treated with bevacizumab in 2011 and with ranibizumab in 2021. Retreatment rates were comparable in 2011 and 2021.

CONCLUSION

Data from two different ROP registries can be aligned and jointly analysed. The analysis reveals a paradigm shift in treatment modalities, from predominantly laser to anti-VEGF, and within the anti-VEGF group from bevacizumab to ranibizumab in Germany. In addition, there was a trend towards earlier treatment in 2021.

Impact of lens autofluorescence and opacification on retinal imaging

BACKGROUND

Retinal imaging, including fundus autofluorescence (FAF), strongly depends on the clearness of the optical media. Lens status is crucial since the ageing lens has both light-blocking and autofluorescence (AF) properties that distort image analysis. Here, we report both lens opacification and AF metrics and the effect on automated image quality assessment.

METHODS

227 subjects (range: 19-89 years old) received quantitative AF of the lens (LQAF), Scheimpflug, anterior chamber optical coherence tomography as well as blue/green FAF (BAF/GAF), and infrared (IR) imaging. LQAF values, the Pentacam Nucleus Staging score and the relative lens reflectivity were extracted to estimate lens opacification. Mean opinion scores of FAF and IR image quality were compiled by medical readers. A regression model for predicting image quality was developed using a convolutional neural network (CNN). Correlation analysis was conducted to assess the association of lens scores, with retinal image quality derived from human or CNN annotations.

RESULTS

Retinal image quality was generally high across all imaging modalities (IR (8.25±1.99) >GAF >BAF (6.6±3.13)). CNN image quality prediction was excellent (average mean absolute error (MAE) 0.9). Predictions were comparable to human grading. Overall, LQAF showed the highest correlation with image quality grading criteria for all imaging modalities (eg, Pearson correlation±CI -0.35 (-0.50 to 0.18) for BAF/LQAF). BAF image quality was most vulnerable to an increase in lenticular metrics, while IR (-0.19 (-0.38 to 0.01)) demonstrated the highest resilience.

CONCLUSION

The use of CNN-based retinal image quality assessment achieved excellent results. The study highlights the vulnerability of BAF to lenticular remodelling. These results can aid in the development of cut-off values for clinical studies, ensuring reliable data collection for the monitoring of retinal diseases.

Personalized Lens Correction Improves Quantitative Fundus Autofluorescence Analysis

Purpose

Quantitative fundus autofluorescence (QAF) currently deploys an age-based score to correct for lens opacification. However, in elderly people, lens opacification varies strongly between individuals of similar age, and innate lens autofluorescence is not included in the current correction formula. Our goal was to develop and compare an individualized formula.

Methods

One hundred thirty participants were examined cross-sectionally, and a subset of 30 participants received additional multimodal imaging 2-week post-cataract-surgery. Imaging included the Scheimpflug principle, anterior chamber optical coherence tomography (AC-OCT), lens quantitative autofluorescence (LQAF), and retinal QAF imaging. Among the subset, least absolute shrinkage and selection operator regression and backward selection was implemented to determine which lens score best predicts the QAF value after lens extraction. Subsequently, a spline mixed model was applied to the whole cohort to quantify the influence of LQAF and Scheimpflug on QAF.

Results

Age and LQAF measurements were found to be the most relevant variables, whereas AC-OCT measurements and Scheimpflug were eliminated by backward selection. Both an increase in Scheimpflug and LQAF values were associated with a decrease in QAF. The prediction error of the spline model (mean absolute error [MAE] ± standard deviation) of 32.2 ± 23.4 (QAF a.u.) was markedly lower compared to the current age-based formula MAE of 96.1 ± 93.5. Both smooth terms, LQAF (P < 0.01) and Scheimpflug (P < 0.001), were significant for the spline mixed model.

Conclusions

LQAF imaging proved to be the most predictive for the impact of the natural lens on QAF imaging. The application of lens scores in the clinic could improve the accuracy of QAF imaging interpretation and might allow including aged patients in future QAF studies.

[Survey on blood thinning therapy in patients with age-related macular degeneration]

BACKGROUND

Patients with age-related macular degeneration (AMD) often receive concomitant systemic blood thinning medications. These are known to increase the risk of severe hemorrhage also in connection with AMD, which can lead to extensive subretinal hemorrhaging.

OBJECTIVE

The purpose of this study was to investigate the proportion of patients with AMD and concomitant blood thinning treatment, including the type and reason for blood thinning treatment.

METHODS

This survey was prospectively conducted at the University Eye Hospital, Bonn, Germany. Volunteers were recruited during retinal consultations and the consultations for intravitreal injections (IVOM).

RESULTS

The questionnaire was completed by 178 patients. The mean age was 81.7 years (58-100) and 101 patients (57.7%) were undergoing blood thinning treatment. The majority of patients were taking antiplatelet agents (n = 59; 58.4%), especially ASA (n = 55; 54.5%). Direct oral anticoagulants (DOAC) were taken by 33 patients (32.7%), including most frequently apixaban (17.8%). Vitamin K antagonists (VKA) was taken by 4 patients (4%). The most common reason for blood thinning treatment was atrial fibrillation (n = 32, 31.7%), followed by stent implantation (n = 20, 19.8%) and stroke (n = 12, 11.9%) but 13 patients (12.9%) did not know why they were undergoing blood thinning treatment. No clear indications for the use of blood thinners were found in 31 patients (30.7%).

CONCLUSION

A large proportion of patients with AMD undergo blood thinning treatment; however, not every patient has a clear indication. Due to the increased risk of bleeding, the use of blood thinners should be critically evaluated in close cooperation with primary care physicians and cardiologists.

Treated Cases of Retinopathy of Prematurity in Germany: 10-Year Data from the Retina.net Retinopathy of Prematurity Registry

PURPOSE

To analyze changes in demographic parameters and retreatment patterns over a 10-year period in a clinical routine setting of infants with retinopathy of prematurity (ROP) requiring treatment documented in the German Retina.net ROP registry.

DESIGN

Multicenter, noninterventional, observational registry study recruiting patients treated for ROP.

SUBJECTS

A total of 692 eyes of 353 infants treated for ROP were documented in the Retina.net ROP registry over a 10-year period between 2011 and 2020. These cases cover about 15% of all infants treated for ROP in Germany.

METHODS

The Retina.net ROP registry was established in 2012 to jointly collect information on infants treated for ROP. The database collects information on demographic parameters (gestational age [GA], birth weight, neonatal comorbidities) as well as treatment parameters (type of treatment, weight and age at treatment, and stage of ROP). A total of 19 centers contributed to the analysis. This is the 10-year analysis of data from 2011 to 2020, in which we focus on changes over time regarding the respective parameters.

MAIN OUTCOME MEASURES

Changes over time in demographic parameters and treatment patterns for ROP in Germany.

RESULTS

The overall incidence of treatment requiring ROP was 3.5% of all infants screened for ROP at participating centers. Gestational age, weight at birth, and weight at treatment remained stable over the 10-year period, whereas postmenstrual and postnatal age at treatment increased moderately but statistically significantly over the years. The most prevalent ROP severity stage at treatment was stage 3+ in zone II (76.6% of all treated eyes). Treatment patterns changed considerably from predominantly laser treatments in 2011 (75% of all treated eyes) to predominantly ranibizumab treatments in 2020 (60.9% of all treated eyes). The overall retreatment rate was 15.6%. Retreatment rates differed between initial treatment modalities (14.1% after laser coagulation, 12% after bevacizumab and 24.5% after ranibizumab). Treatment-associated systemic or ophthalmic complications were rare.

CONCLUSIONS

This data analysis represents one of the largest documented cohorts of infants treated for ROP. The data on demographic parameters and treatment patterns provide useful information for further improvement of ROP management.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Early Vitrectomy with Silicone Oil Tamponade in the Management of Postoperative Endophthalmitis

Background: Early vitrectomy for postsurgical endophthalmitis may improve visual acuity outcomes. Silicone oil as a tamponade has some potential benefits in the management of endophthalmitis. This study aims to evaluate the use of a silicone oil tamponade in the surgical management of endophthalmitis. Material and Methods: All patients with a pars plana vitrectomy with silicone oil tamponade for postsurgical endophthalmitis at the Department of Ophthalmology, University of Bonn, Germany, between 2017 and 2021 were retrospectively reviewed. We included all preoperative data, including BCVA at diagnosis, clinical findings, and symptoms. For every follow-up visit, we looked at BCVA and complications. Results: In total, 82 patients were included in this study. The mean follow-up was 13.1 months (range 1-58 months). An intravitreal injection was the cause in 42 patients (51.2%) and cataract surgery in 29 patients (35.4%). The mean interval between the causing event and the date of onset was 8.8 days (range, 1-59 days). The most prevalent pathogen was Staphylococcus epidermidis in 16 patients (19.5%). In 47 patients (57.3%), no pathogen was found. The initial best-corrected visual acuity was 2.1 logMAR and improved significantly to 1.0 logMAR after six months (p < 0.001) and 1.1 logMAR after 1 year (p < 0.001). In a multivariate analysis, a low BCVA at diagnosis (p = 0.041) was a significant predictor for poor visual acuity outcomes. A total of 17 patients (20.1%) developed postoperative complications. Five patients (6.1%) needed an anterior chamber washout with repeated injections of antibiotics. Two patients (2.4%) had persistent fibrin and were treated with YAG-laser treatment. Three patients (6.7%) developed a retinal detachment. Two patients (2.4%) had persistent corneal decompensation with endothelial cell loss and received perforating keratoplasty. We performed a matched-pair analysis (n = 30, each group n = 15) to compare a silicone oil tamponade with BSS at the end of surgery. The visual acuity outcome showed no significant differences (BCVA after one year: 1.17 logMAR in eyes with silicone oil and 0.90 logMAR in eyes with BSS; p = 0.684). Conclusions: In our study, a vitrectomy with silicone oil tamponade in the surgical management of postoperative endophthalmitis led to a significant improvement in visual acuity and had a low complication rate. Low BCVA at diagnosis was significantly associated with poor visual acuity outcomes. A comparison of silicone oil and BSS at the end of surgery showed similar results.

Clinical outcomes of the PAUL® glaucoma implant: One-year results

BACKGROUND

To report one-year outcomes from a single-centre cohort undergoing PAUL® Glaucoma Implant (PGI) surgery.

METHODS

Retrospective review of patients undergoing PGI surgery at the University Eye Hospital Bonn, Germany, from April 2021 to September 2021.

RESULTS

Forty-five eyes of 41 patients were included. Qualified and complete success rates (95% CI) were 95.6% (88.9%-100%) and 73.3% (60%-86.7%) for Criterion A (IOP ≤ 21 mmHg), 84.4% (73.3%-93.3%) and 74.4% (51.1%-80.0%) for Criterion B (IOP ≤ 18 mmHg), 62.2% (48.9%-75.6%) and 46.7% (31.2%-62.2%) for Criterion C (IOP ≤ 15 mmHg) and 26.7% (13.3%-40.0%) and 22.2% (11.1%-33.3%) for Criterion D (IOP ≤ 12 mmHg), respectively. Mean IOP decreased from 26.1 mmHg (7-48 mmHg) to 12.0 mmHg (3-24 mmHg) (reduction of 48.83%) after 12 months with a reduction of IOP-lowering agents from 0.5 (0-3). One eye (2.2%) needed an injection of viscoelastic due to significant hypotony with AC shallowing, and four eyes (8.9%) developed choroidal detachments due to hypotony which resolved without further interventions after 6 weeks. Three patients (6.7%) developed tube exposure which required conjunctival revision with an additional pericardial patch graft. An intraluminal prolene stent was removed in 19 eyes (42.2%) after a mean time period of 8.4 months (2-12 m). Mean IOP before the removal was 21.9 mmHg (12-38 mmHg) and decreased to 11.3 mmHg (6-16 mmHg).

CONCLUSIONS

PGI surgery is an effective procedure for reducing IOP and pressure-lowering therapy. An intraluminal prolene stent impedes hypotony in the early postoperative phase and enables further IOP lowering without additional interventions during the postoperative course.

Influence of a Prostaglandin F2α Analogue on Corneal Hysteresis and Expression of Extracellular Matrix Metalloproteinases 3 and 9

Purpose

Low corneal hysteresis (CH) is associated with an increased risk of glaucoma. Prostaglandin analogue (PGA) eye drops may exert their intraocular pressure (IOP)-lowering effect partially by increasing CH.

Methods

Twelve pairs of organ-cultured human donor corneas were used in an ex vivo model. In each case, one cornea was treated with PGA (Travoprost) for 30 days, whereas the other served as an untreated control. IOP levels were simulated in an artificial anterior chamber model. CH was measured using the Ocular Response Analyzer (ORA). Corneal expression of matrix-metalloproteinases (MMPs) was assessed by immunhistochemistry and real-time polymerase chain reaction (RT-PCR).

Results

Increased CH was observed in the PGA-treated corneas. However, at IOP between 10 and 20 mm Hg, CH was increased in PGA-treated corneas (13.12 ± 0.63 mm Hg; control: 12.34 ± 0.49 mm Hg), although not significantly (P = 0.14). CH was significantly increased at higher IOP levels (21-40 mm Hg; PGA-treated: 17.62 ± 0.40 mm Hg; control: 11.60 ± 0.39, P < 0.0001). Treatment with PGA resulted in increased expression of MMP-3 and MMP-9.

Conclusions

CH was increased after exposure to PGA. However, this increase was significant only in eyes with higher IOP (>21 mm Hg). A significant increase in MMP-3 and -9 was observed in PGA-treated corneas, indicating structural changes in corneal biomechanics caused by PGA.

Translational Relevance

PGAs alter biomechanical structures by directly upregulating MMP-3 and -9, and the increase in CH is dependent on the level of IOP. Therefore, PGAs may have a greater effect when baseline IOP is higher.

Local Recurrence in Choroidal Melanomas following Robotic-Assisted Radiosurgery (CyberKnife)

Introduction

Tumor recurrence in choroidal melanoma has been associated with decreased overall survival due to metastatic spreading. To detect risk factors of local recurrence and side effects, we analyzed tumor planning and treatment parameters in patients with recurrence of choroidal melanoma after treatment with robotic-assisted radiosurgery (CyberKnife).

Methods

Six hundred ninety-four patients treated with CyberKnife between 2005 and 2019 were retrospectively reviewed. Age, gender, best-corrected visual acuity, tumor height, and diameter were recorded. Treatment planning and radiation doses were reviewed. Salvage therapy, overall survival, metastasis, and complications were recorded.

Results

Seventy-four patients showed local recurrence. Local recurrence occurred after 42.1 months post CyberKnife treatment (mean; range: 5-100 months). Fourteen out of 74 patients (18.9%) died during follow-up. Recurrence treatment included enucleation in 51 patients (68.9%) and radiosurgery in 19 patients (25.7%). Treatment planning without contrast medium MRI, radiation dose of less than 21 Gy, and insufficient margin delineation were identified as risk factors incrementing local control.

Discussion

Robotic-assisted radiosurgery (CyberKnife) is a suitable treatment option for large choroidal melanoma up to 12 mm. Patients with significantly better visual acuity received repeat CyberKnife treatment as salvage therapy and showed an eye retention rate of 81%.

Robotic CyberKnife Radiosurgery for the Treatment of Choroidal and Ciliary Body Melanoma

PURPOSE

To present the results of robotic-assisted radiosurgery in choroidal and ciliary body melanomas treated at the Department of Ophthalmology of Ludwig-Maximilians-University and the European CyberKnife Center in Munich, Germany.

DESIGN

Interventional case series METHODS: This retrospective study included 594 consecutive patients referred to our clinic for the treatment of choroidal and ciliary body melanomas with robotic radiosurgery (CyberKnife) from 2005 to 2019. Eye retention, local control and disease-specific survival rates were calculated as Kaplan-Meier and actuarial estimates. The impact of prescription dose, tumor size, and ciliary body involvement was assessed by likelihood ratio tests and Cox regression.

RESULTS

Among all patients who were staged according to the TNM classification system (8th edition), 22.7% were I, 57.9% were II, 18.9% were III, and 0.5% were IV. Median apical tumor height and base diameter were 5.8 and 11.4 mm. The mean follow-up was 41.7 months. Local control after 3 and 5 years was 92.0% (95% CI = 88.2%-94.7%) and 84.3% (95% CI = 77.9%-89.0%), respectively, for 21 to 22 Gy and 86.9% (95% CI = 79.7%-91.7%) and 77.7% (95% CI = 68.5%-84.6%), respectively, when treated with 20 Gy or less. Eye retention was achieved in 89.9% and 81.0% after 3 and 5 years with 21 to 22 Gy and 85.9% and 80.0% for 20 Gy or less. Disease-specific survival rates were 93.1% (95% CI = 90.2%-95.2%) after 3 years, 89.8% (95% CI = 86.0%-92.6%) after 5 years, and 87.8% (95% CI = 82.8%-91.4%) after 7 years.

CONCLUSIONS

This is the largest series of patients treated for choroidal and ciliary body melanomas with CyberKnife. Our results reflect an improvement in the outcome of CyberKnife therapy for patients with choroidal and ciliary body melanoma treated with single-session radiosurgery in the last decade.

Antiplatelet and anticoagulant therapy in patients with submacular hemorrhage caused by neovascular age-related macular degeneration

Purpose

Patients with extensive submacular hemorrhage (SMH) caused by age-related macular degeneration (AMD) have a poor visual prognosis despite surgical intervention. Systemic blood-thinning drugs, which are commonly prescribed in the same age group, are known to increase the risk of severe hemorrhage in many parts of the body. This study aimed to investigate whether systemic blood-thinning drugs have an impact on the severity of SMH and if there are differences between the different types of blood-thinning medication.

Methods

We reviewed the medical records of patients who suffered from surgically treated SMH between 2020 and 2022. All patients received a full ophthalmologic examination upon presentation including best-corrected visual acuity (BCVA) and optical coherence tomography. Other characteristics that were recorded included size of hemorrhage, blood-thinning therapy, and reason for intake.

Results

A total of 115 patients with a mean age of 82 years were included in this retrospective analysis. Eighty-three patients (72.2%) were on blood-thinning therapy. The mean size of SMH was 32.01 mm2. Mean BCVA at initial presentation was 1.63 logMAR and 1.59 logMAR 1 year after surgery. The size of SMH was significantly larger in patients on blood-thinning medication (35.92 mm2 vs. 21.91 mm2) (p = 0.001) and their BCVA postoperatively was worse with 1.68 logMAR compared to 1.30 logMAR after 1 year (p = 0.503). Patients with vitamin K antagonists had larger SMH size and worse outcomes regarding BCVA compared to direct oral anticoagulants.

Conclusion

Blood thinners in patients with AMD affect the severity of SMH. Consequently, the indication for their intake should be critically evaluated.

Impact of COVID-19 before and after 2020 on Retinal Detachment Management in a Tertiary Eye Hospital in Germany

INTRODUCTION

COVID-19 has had a tremendous impact on our everyday life. A growing body of evidence indicates that subsequent lockdowns and fear of exposure may have impacted patient care. We analyzed data on incidence and time to surgery in cases of rhegmatogenous retinal detachments (RRD) at three defined time points before, during, and 1 year after the first lockdown period in Germany.

METHODS

In this single-center study, we identified all patients who were admitted and treated for a primary RRD in April and May 2020, the time of the first lockdown period in Germany, and compared them with cases of the same time period in the years 2019 and 2021. The time from first occurrence of symptoms to surgery as well as visual outcome was analyzed.

RESULTS

A total of 192 patients presented to our tertiary academic referral center with a RRD during the months of April and May in 2019 (72 patients), 2020 (62 patients), and 2021 (58 patients) and were included in this study. There were no significant differences with regard to gender and age. In 2019, the time interval between occurrence and presentation to our hospital amounted to a mean of 5.96 days and in 2021 to mean of 5.45 days. However, in 2020, the time between occurrence and presentation was significantly longer with a mean of 15.36 days. The number of patients presenting with a macula-on retinal detachment was also lowest in 2020 (39.2%) compared to 2019 (50.7%) and 2021 (50.0%). Furthermore, with 1.24 logMAR the mean BCVA upon initial presentation was lower in 2020 compared to 0.93 logMAR in 2019 and 1.06 logMAR in 2021. Six to twelve weeks following surgery, visual acuity had improved in 56.1% of patients in 2019 and 60.0% of patients in 2021 as compared to 59.0% in 2020.

CONCLUSION

We found significant differences in terms of elapsed time from first symptoms to surgical management for patients in 2020 in comparison with the same time period in 2019 and 2021. Less strict lockdown policies appear to impact patient behavior and patient care. Further measures, such as questionnaires, might help address which measures may provide safer circumstances for patients to consult health care providers in the case of future strict lockdowns.

Der Intraokulardruck nach Netzhauteingriffen

Zusammenfassung - Deutsch Netzhauteingriffe können zu einem erhöhten Augeninnendruck führen. Die Ursachen hierfür sind vielfältig und schließen mechanische aber auch pharmakologische Gründe ein. Die Therapie besteht zunächst aus einer Lokaltherapie mit drucksenkenden Augentropfen. Bei unzureichendem Ansprechen sind chirurgische Eingriffe indiziert. Summary - English Retinal surgery can lead to an elevated intraocular pressure. The causes for this are manifold and include mechanical but also pharmacological reasons. Therapy consists initially of topical therapy with pressure-lowering eye drops. In case of inadequate response, surgical interventions are indicated.

LONG-TERM EFFICACY OF FLUOCINOLONE IN EYES WITH IRIS-LENS DIAPHRAGM DISRUPTION AND PCME WITH MEDICATION FIXED IN THE SCLERA (MEFISTO)

PURPOSE

The aim of our prospective off-label, interventional clinical trial was to evaluate the efficacy and safety of the fluocinolone-loop-anchoring technique over two years in eyes with iris-lens diaphragm disruption and pseudophakic cystoid macular edema.

METHODS

In 10 eyes, scleral fixation of fluocinolone implant was performed. Main outcome measures were the development of best-corrected visual acuity (BCVA), central retinal thickness over 24 months, and general safety of the procedure.

RESULTS

A significant improvement to 0.57 ± 0.38 log MAR (Snellen 20/80) (range 0-1.30) was observed (P = 0.003) at 1 month. Further improvement to 0.45 ± 036 log MAR (Snellen 20/60) was observed until month 18 (P = 0.081). Mean central retinal thickness decreased by 22% from 601.6 ± 235.5 µm to 449.1 ± 128.9 µm at 1 month. In one patient, the implant has to be removed at Month 7 because of elevated intraocular pressure and one patient after globe rupture had a retinal redetachment at Month 4.

CONCLUSION

In this study, we showed that the treatment of recalcitrant pseudophakic cystoid macular edema with scleral fixated fluocinolone implant in eyes with disruption of the iris-lens diaphragm provides good anatomical and functional results with a reasonable safety profile over 24 months in eyes where pseudophakic cystoid macular edema is otherwise difficult to treat and often left untreated.

Robotic CyberKnife radiosurgery for small choroidal melanomas

Plaque brachytherapy is the most common procedure for the treatment of small choroidal melanoma, especially in posteriorly located tumors. However, there is only little information on outcome after treatment with stereotactic radiosurgery, for example, CyberKnife radiosurgery. We reviewed patients with choroidal melanoma (maximum tumor height 4 mm) treated with CyberKnife radiosurgery. Demographic information, tumor dimension, complications, metastasis and overall survival during the whole follow-up were tracked and analyzed with a specific focus on local tumor control and potential risk factors. One hundred eighty-eight patients (102 female, 54.2%) with a median age of 63 years [interquartile range (IQR): 54-73 years] were analyzed over a median of 46 months (IQR: 24-62 months). Metastasis occurred in 14 patients (7.4%) in median of 18 months after treatment (IQR: 13-47 months) and survival was achieved in 178 patients (94.7%). Within the observation period, eye retention was observed in 166 patients (88.3%). Superior local control was achieved in patients who received a prescription dose of at least 21 Gy or more (91.6%; P = 0.04). Other potential risk factors incrementing local control were treatment planning with missing MRI in advance and too small target delineation during the planning process. Radiosurgery (CyberKnife) in a single, outpatient procedure is suitable for the treatment of small choroidal melanoma. We found local control rate after 3 years compared to the standard treatment with plaque brachytherapy. On the study side, 15 years of CyberKnife treatment allowed to identify risk factors that might increment local control and thus improve treatment regimens.

Anti-angiogenic properties of rapamycin on human retinal pericytes in an in vitro model of neovascular AMD via inhibition of the mTOR pathway

PURPOSE

Choroidal neovascularizations (CNV) are partially stabilized through a coverage of pericytes leading to a partial anti-VEGF resistence. Drugs licensed for neovascular AMD (nAMD) do not take this mechanical and growth factor-driven CNV stability into account. The purpose of this work was to see if inhibiting the mammalian target of rapamycin (mTOR) may successfully block angiogenic cellular pathways in primary human retinal pericytes in an in vitro model of nAMD.

METHODS

The mTOR inhibitor rapamycin was used to treat human retinal pericytes (HRP) at doses ranging from 0.005 to 15 g/ml. A modified metabolism-based XTT-Assay was used to assess toxicity and anti-proliferative effects. A scratch wound experiment showed the effects on migration. On Cultrex basement membrane gels, the influence of rapamycin on the development of endothelial cell capillary-like structures by human umbilical vein vascular endothelial cells (HUVEC) in the absence and presence of pericytes was investigated.

RESULTS

Rapamycin showed no signs of toxicity within its range of solubility. The drug showed dose dependent anti-proliferative activity and inhibited migration into the scratch wound. Endothelial cell tube formation in a HUVEC monoculture was effectively inhibited at 45%. A co-culture of HUVEC with pericytes on Cultrex induced endothelial tube stabilization but was disrupted by the addition of rapamycin leading to degradation of 94% of the tubes.

CONCLUSIONS

Rapamycin allows for an efficient modulation of aspects of angiogenesis in pericytes via mTOR-modulation in vitro. Further studies are needed to elucidate whether rapamycin may have an impact on CNV in nAMD in vivo.

TPC2 promotes choroidal angiogenesis and inflammation in a mouse model of neovascular age-related macular degeneration

This study identifies the endolysosomal two-pore channel TPC2 as a potential novel drug target for age-related macular degeneration (AMD). Inhibition of TPC2 reduces two key clinical hallmarks of the AMD, retinal inflammation and formation of leaky choroi.

Age-related macular degeneration (AMD) is the most common cause of blindness among the elderly and can be classified either as dry or as neovascular (or wet). Neovascular AMD is characterized by a strong immune response and the inadequate release of cytokines triggering angiogenesis and induction of photoreceptor death. The pathomechanisms of AMD are only partly understood. Here, we identify the endolysosomal two-pore cation channel TPC2 as a key factor of neovascularization and immune activation in the laser-induced choroidal neovascularization (CNV) mouse model of AMD. Block of TPC2 reduced retinal VEGFA and IL-1β levels and diminished neovascularization and immune activation. Mechanistically, TPC2 mediates cationic currents in endolysosomal organelles of immune cells and lack of TPC2 leads to reduced IL-1β levels in areas of choroidal neovascularization due to endolysosomal trapping. Taken together, our study identifies TPC2 as a promising novel therapeutic target for the treatment of AMD.

Robotic-assisted radiosurgery for the treatment of vasoproliferative tumours

PURPOSE

Vasoproliferative tumours (VPT) are a rare but benign entity that can lead to severe visual acuity deterioration. There is no standard of care, and depending on the degree of clinical features, including tumour size and dissemination, visual acuity and subretinal fluid, treatment options include observation, cryotherapy and brachytherapy. Particularly in larger tumours, brachytherapy has advantages over other options, although higher radiation doses and the need for surgical application are disadvantages of this otherwise effective treatment option. CyberKnife radiosurgery might represent an alternative therapeutic option as no surgical intervention is needed and radiation doses are lower.

METHODS

All patients diagnosed with vasoproliferative tumors who were treated with CyberKnife radiosurgery with a minimum follow-up time of 12 months were included in this case series. We recorded visual acuity, number of lesions, central retinal thickness with optical coherence tomography (OCT) and reflectivity using A-scan standardizes echography every three months.

RESULTS

A total of four patients with a median age of 34 years (range: 24 - 51) who were observed over an average of 26.5 months (range: 17 - 49 months) matched our inclusion criteria. We appreciated stabilization or increase in visual acuity in all four patients and a regression in tumour thickness with subsequent increase in internal reflectivity as a marker of increasing fibrosis.

CONCLUSION

We observed good visual and functional outcome following CyberKnife therapy for VPT. We believe that further studies should be pursued to evaluate CyberKnife therapy for the treatment of VPT not treatable with cryo- or lasertherapy.

Short-term real-world outcomes following intravitreal brolucizumab for neovascular AMD: SHIFT study

BACKGROUND

Brolucizumab has recently been approved in Europe as a novel treatment for patients with neovascular age-related macular degeneration (nAMD). We report on early experiences with real-world outcomes of switch to brolucizumab therapy in previously anti-vascular endothelial growth factor (anti-VEGF)-treated patients.

METHODS

Patients with recalcitrant nAMD were switched to brolucizumab therapy. Functional and structural parameters 4 weeks after first brolucizumab injection were evaluated including best-corrected visual acuity (BCVA (logMAR)), foveal centre point (FCP (µm)), central subfield retinal thickness (CSRT (µm)) and macular volume (mm³).

RESULTS

Sixty-three eyes of 57 patients with nAMD (52.6% females) with a mean (±SD) age of 79.5±6.7 years were included. Mean change of BCVA was 0.03±0.14 logMAR (p=0.115). Significant reductions were recorded for FCP with a mean (±SD) change of -66.81±72.63 µm, -66.76±60.71 µm for CSRT and -0.27±0.24 mm³ for macular volume (all p<0.001). Intraocular inflammation was observed in seven eyes of seven patients, including one case of retinal vasculitis.

CONCLUSIONS

The results of the SHIFT study indicate that switch to brolucizumab may represent a treatment option in patients with nAMD poorly responsive to other anti-VEGF agents. Further long-term analyses appear prudent to assess efficacy and safety of brolucizumab in a routine clinical setting.

Robotic assisted CyberKnife radiosurgery for the treatment of iris melanoma

Iris melanoma is a rare form of uveal melanoma with potential metastic spread. Treatment options include surgical resection, enucleation or irradiation. We analysed visual outcome, complication appearance and management in eight patients with iris melanoma following robotic-assisted CyberKnife treatment. Consecutive patients from the Department of Ophthalmology at University of Munich were included in the study if they had an iris melanoma that was treated with CyberKnife and had a minimum follow-up of 12 months. We evaluated tumor thickness, largest diameter, visual acuity and complications. 8 patients were included in this report. The median age was 74 years (range: 53-86 years). The median follow-up was 23 months (range 12-48 months). Tumor thickness decreased from 2.1 to 1.4 mm on average. Four out of eight patients showed stable or increased visual acuity compared to visual acuity at first visit. We did not find a correlation of applied radiation volume or radiation dose on visual outcome. Radiation keratopathy was the most common complication in five patients. No recurrences were noted. Robotic-assisted radiosurgery following CyberKnife is a promising non-invasive, single session treatment option for iris melanoma with comparable results regarding recurrence rate or complications to brachytherapy and proton beam therapy. All included patients showed good visual outcome.

Robotic assisted CyberKnife radiosurgery for the treatment of choroidal metastasis

PURPOSE

Choroidal metastases occur in many patients with systemic cancer and limit quality of life due to visual deterioration or pain. The limited prognosis of these patients demand treatment approaches that aim at a quick response and easy application. We evaluated a robotic assisted radiosurgery device, the CyberKnife, in the treatment of choroidal metastasis.

METHODS

Following retrobulbar anaesthesia, target volume was defined by an interdisciplinary team using gadolinium-contrast-enhanced MRI, computer tomography (CT) as well as all previously obtained clinical data. Radiation was delivered in a single fraction with a CyberKnife at a radiation dose of 21 Gy with a 70% isodose. We evaluated tumour height, reflectivity, visual acuity and side effects over the course of the follow-up.

RESULTS

A total of four patients were included in this report. Mean follow-up time was 31 months, and all patients showed decreased tumour volume and signs of fibrosis during follow-up. One patient remained stable in terms of visual acuity, two patients lost visual acuity and one patient improved and had a functional visual acuity at last follow-up. One patient developed radiation retinopathy with subsequent neovascular glaucoma that needed further management. All other patients did not show any signs of radiation induced side effects.

CONCLUSION

We report on the outcome of robotic CyberKnife radiosurgery in the treatment of uveal metastasis. We believe that single session, outpatient treatment delivery that can be facilitated with CyberKnife radiosurgery offer some benefits for this particularly sick group of patients.

Comparison of variables measured with a Scheimpflug device for evaluation of progression and detection of keratoconus

Keratoconus is a progressive ectatic corneal disorder, which can result in severe visual impairment. The new ABCD keratoconus classification system allows differentiated description of the disease. Aim of the study was to evaluate the components of this novel staging system (ARC, PRC, thinnest pachymetry) as well as topometric indices, deviation of normality indices, and other parameters in terms of repeatability and reliability. 317 eyes with keratoconus were examined twice with a Scheimpflug device (Pentacam, Oculus). Bland Altman analysis and intraclass correlations were carried out to evaluate the parameters repeatability and reliability. Apart from IHA (ICC = 0.730), all parameters showed excellent reliability (ICC > 0.900). ARC, PRC, thinnest pachymetry, Kmax, CKI, KI, Rmin, and Progression Avg were the best repeatable parameters with relative repeatability values < 2.5%. Other parameters performing well in terms of repeatability were IHD, ISV, IVA, and final D (RR < 13%). Regression analysis revealed consistently high repeatability along all stages of keratoconus for PRC, thinnest pachymetry, and CKI. All parameters of the ABCD staging system showed excellent reliability and repeatability, PRC and thinnest pachymetry even at all stages of keratoconus and can consequently be reliably used in the determination of keratoconus progression.

IGF1, serum glucose, and retinopathy of prematurity in extremely preterm infants

BACKGROUND

Hyperglycemia, insulin insensitivity, and low IGF1 levels in extremely preterm infants are associated with an increased risk of retinopathy of prematurity (ROP), but the interactions are incompletely understood.

METHODS

In 117 extremely preterm infants, serum glucose levels and parenteral glucose intake were recoded daily in the first postnatal week. Serum IGF1 levels were measured weekly. Mice with oxygen-induced retinopathy alone versus oxygen-induced retinopathy plus streptozotocin-induced hyperglycemia/hypoinsulinemia were assessed for glucose, insulin, IGF1, IGFBP1, and IGFBP3 in blood and liver. Recombinant human IGF1 was injected to assess the effect on glucose and retinopathy.

RESULTS

The highest mean plasma glucose tertile of infants positively correlated with parenteral glucose intake [r₍₃₉₎ = 0.67, P < 0.0001]. IGF1 plasma levels were lower in the high tertile compared with those in low and intermediate tertiles at day 28 (P = 0.038 and P = 0.03). In high versus lower glucose tertiles, ROP was more prevalent (34 of 39 versus 19 of 39) and more severe (ROP stage 3 or higher; 71% versus 32%). In oxygen-induced retinopathy, hyperglycemia/hypoinsulinemia decreased liver IGF1 expression (P < 0.0001); rh-IGF1 treatment improved normal vascular regrowth (P = 0.027) and reduced neovascularization (P < 0.0001).

CONCLUSION

In extremely preterm infants, high early postnatal plasma glucose levels and signs of insulin insensitivity were associated with lower IGF1 levels and increased ROP severity. In a hyperglycemia retinopathy mouse model, decreased insulin signaling suppressed liver IGF1 production, lowered serum IGF1 levels, and increased neovascularization. IGF1 supplementation improved retinal revascularization and decreased pathological neovascularization. The data support IGF1 as a potential treatment for prevention of ROP.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02760472 (Donna Mega).

FUNDING

This study has been supported by the Swedish Medical Research Council (14940, 4732, 20144-01-3, and 21144-01-3), a Swedish government grant (ALFGB2770), Lund medical faculty grants (ALFL, 11615 and 11601), the Skåne Council Foundation for Research and Development, the Linnéa and Josef Carlsson Foundation, the Knut and Alice Wallenberg Foundation, the NIH/National Eye Institute (EY022275, EY017017, EY017017-13S1, and P01 HD18655), European Commission FP7 project 305485 PREVENT-ROP, Deutsche Forschungsgemeinschaft (CA-1940/1-1), and Stiftelsen De Blindas Vänner.

In extremely preterm infants, high early postnatal plasma glucose levels and signs of insulin insensitivity were associated with lower IGF1 levels and increased retinopathy of prematurity severity.

Gender-related differences in patients treated with intravitreal anti-vascular endothelial growth factor medication for diabetic macular oedema

BACKGROUND

Diabetes prevalence is constantly rising, involving the eyes with damage including development of diabetic macular oedema. Since 2012, intravitreal anti-vascular endothelial growth factor medication is available for diabetic macular oedema treatment. Endocrinological studies have shown that fewer women are affected by diabetes. However, when affected, they exhibit more severe diabetic complications than men. We have investigated gender-related differences in diabetic macular oedema and outcome in an ophthalmological tertiary referral hospital.

METHODS

We included 88 patients (54 males and 34 females) with 112 eyes (68 male and 44 female) having clinically significant diabetic macular oedema, treated with anti-vascular endothelial growth factor medication. A 1 year follow-up was performed in all patients (visual acuity and optical coherence tomography). Previous retinal surgery was an exclusion criterion, as were other retinal pathologies.

RESULTS

The mean visual acuity and mean central retinal thickness at baseline were 0.53 logMAR (male 0.49 and female 0.595) and 469 μm (male 452 μm and female: 494 μm), respectively. After 360 days, mean visual acuity changed by -0.07 (±0.36) logMAR (male -0.11 and female +0.01) and mean central retinal thickness changed by -119 μm (male -113 μm and female -127 μm). For visual acuity, a significant difference was noted at baseline (p = 0.02) and at 1 year (p < 0.001). Males received 5.6 injections and females received 5.68 injections in 1 year.

CONCLUSION

Our study showed that female patients with diabetic macular oedema were diagnosed with and treated for diabetic macular oedema at a stage when visual acuity and optical coherence tomography were worse than those in their male counterparts. This gender difference could not be reduced, despite similar numbers of injections. Female diabetic patients should therefore be assessed early for ophthalmological pathologies.

Photoreceptor glucose metabolism determines normal retinal vascular growth

The neural cells and factors determining normal vascular growth are not well defined even though vision‐threatening neovessel growth, a major cause of blindness in retinopathy of prematurity (ROP) (and diabetic retinopathy), is driven by delayed normal vascular growth. We here examined whether hyperglycemia and low adiponectin (APN) levels delayed normal retinal vascularization, driven primarily by dysregulated photoreceptor metabolism. In premature infants, low APN levels correlated with hyperglycemia and delayed retinal vascular formation. Experimentally in a neonatal mouse model of postnatal hyperglycemia modeling early ROP, hyperglycemia caused photoreceptor dysfunction and delayed neurovascular maturation associated with changes in the APN pathway; recombinant mouse APN or APN receptor agonist AdipoRon treatment normalized vascular growth. APN deficiency decreased retinal mitochondrial metabolic enzyme levels particularly in photoreceptors, suppressed retinal vascular development, and decreased photoreceptor platelet‐derived growth factor (Pdgfb). APN pathway activation reversed these effects. Blockade of mitochondrial respiration abolished AdipoRon‐induced Pdgfb increase in photoreceptors. Photoreceptor knockdown of Pdgfb delayed retinal vascular formation. Stimulation of the APN pathway might prevent hyperglycemia‐associated retinal abnormalities and suppress phase I ROP in premature infants.

Induction and Readout of Oxygen-Induced Retinopathy

Ischemic retinal diseases can be caused by various pathologies, which often lead to formation of preretinal neovascularization. A very common and well-established model to study normal as well as pathological angiogenic mechanisms in retina is the oxygen-induced retinopathy model in mice. This model is based on oxygen exposure of mouse pups during retinal vascular development, leading to a depletion of retinal capillaries. Upon return to room air, the lack of retinal vasculature results in hypoxia, which in turn induces vascular repair and preretinal neovascularization. In this review, we will focus on the scientific options, practical implementation, and quantification of the OIR model and its potential pitfalls.

Thrombocytopenia is associated with severe retinopathy of prematurity

Retinopathy of prematurity (ROP) is characterized by abnormal retinal neovascularization in response to vessel loss. Platelets regulate angiogenesis and may influence ROP progression. In preterm infants, we assessed ROP and correlated with longitudinal postnatal platelet counts (n = 202). Any episode of thrombocytopenia (<100 × 109/l) at ≥30 weeks postmenstrual age (at onset of ROP) was independently associated with severe ROP, requiring treatment. Infants with severe ROP also had a lower weekly median platelet count compared with infants with less severe ROP. In a mouse oxygen-induced retinopathy model of ROP, platelet counts were lower at P17 (peak neovascularization) versus controls. Platelet transfusions at P15 and P16 suppressed neovascularization, and platelet depletion increased neovascularization. Platelet transfusion decreased retinal of vascular endothelial growth factor A (VEGFA) mRNA and protein expression; platelet depletion increased retinal VEGFA mRNA and protein expression. Resting platelets with intact granules reduced neovascularization, while thrombin-activated degranulated platelets did not. These data suggest that platelet releasate has a local antiangiogenic effect on endothelial cells to exert a downstream suppression of VEGFA in neural retina. Low platelet counts during the neovascularization phase in ROP is significantly associated with the development of severe ROP in preterm infants. In a murine model of retinopathy, platelet transfusion during the period of neovascularization suppressed retinopathy.

3-year-data of combined navigated laser photocoagulation (Navilas) and intravitreal ranibizumab compared to ranibizumab monotherapy in DME patients

PURPOSE

The prospective, comparative evaluation of combined navigated laser photocoagulation and intravitreal ranibizumab in the treatment of diabetic macular edema has shown advantage of a combination therapy compared to ranibizumab monotherapy at year 1 with significantly reduced injections. The purpose of this retrospective study was to determine the long-term visual gains and need of injections in a 3 year-follow-up period.

METHODS

Retrospective analysis of patients of the original study in the long-term follow-up from month 12 to 36. BCVA measurements following the original 1 year study were taken using logMAR charts. Injections were provided with standard of care using PRN, based on change in BCVA and CRT using SD-OCT scans. Main outcome measures were change in BCVA and mean number of injections from 12 to 36 months.

RESULTS

BCVA was stable in both groups from 12 through 36 months, showing a change of 0.16 ± 0.1 log MAR. Following the initial reduction in required injections at month 12, combination therapy patients continued to require 1.3 times fewer injections over the next 24 months (2.91 ± 2.3 vs 3.85±3.7 injections for monotherapy).

CONCLUSIONS

Combination of navigated laser and ranibizumab achieved BCVA gains equivalent to anti-VEGF monotherapy. These results could be maintained through month 36. Required injections were 2.0 injections lower in year 1 and further 1.3 times fewer in year 2 and 3 in the combination group compared to monotherapy. Adding navigated laser photocoagulation to intravitreal anti-VEGF therapy may still represent a superior therapeutic approach to DME patients.

Fibroblast Growth Factor 21 Protects Photoreceptor Function in Type 1 Diabetic Mice

Retinal neuronal abnormalities occur before vascular changes in diabetic retinopathy. Accumulating experimental evidence suggests that neurons control vascular pathology in diabetic and other neovascular retinal diseases. Therefore, normalizing neuronal activity in diabetes may prevent vascular pathology. We investigated whether fibroblast growth factor 21 (FGF21) prevented retinal neuronal dysfunction in insulin-deficient diabetic mice. We found that in diabetic neural retina, photoreceptor rather than inner retinal function was most affected and administration of the long-acting FGF21 analog PF-05231023 restored the retinal neuronal functional deficits detected by electroretinography. PF-05231023 administration protected against diabetes-induced disorganization of photoreceptor segments seen in retinal cross section with immunohistochemistry and attenuated the reduction in the thickness of photoreceptor segments measured by optical coherence tomography. PF-05231023, independent of its downstream metabolic modulator adiponectin, reduced inflammatory marker interleukin-1β (IL-1β) mRNA levels. PF-05231023 activated the AKT-nuclear factor erythroid 2-related factor 2 pathway and reduced IL-1β expression in stressed photoreceptors. PF-05231023 administration did not change retinal expression of vascular endothelial growth factor A, suggesting a novel therapeutic approach for the prevention of early diabetic retinopathy by protecting photoreceptor function in diabetes.

FGF21 Administration Suppresses Retinal and Choroidal Neovascularization in Mice

Pathological neovascularization, a leading cause of blindness, is seen in retinopathy of prematurity, diabetic retinopathy, and age-related macular degeneration. Using a mouse model of hypoxia-driven retinal neovascularization, we find that fibroblast growth factor 21 (FGF21) administration suppresses, and FGF21 deficiency worsens, retinal neovessel growth. The protective effect of FGF21 against neovessel growth was abolished in adiponectin (APN)-deficient mice. FGF21 administration also decreased neovascular lesions in two models of neovascular age-related macular degeneration: very-low-density lipoprotein-receptor-deficient mice with retinal angiomatous proliferation and laser-induced choroidal neovascularization. FGF21 inhibited tumor necrosis α (TNF-α) expression but did not alter Vegfa expression in neovascular eyes. These data suggest that FGF21 may be a therapeutic target for pathologic vessel growth in patients with neovascular eye diseases, including retinopathy of prematurity, diabetic retinopathy, and age-related macular degeneration.

Adiponectin Mediates Dietary Omega-3 Long-Chain Polyunsaturated Fatty Acid Protection Against Choroidal Neovascularization in Mice

Purpose

Neovascular age-related macular degeneration (AMD) is a major cause of legal blindness in the elderly. Diets with omega3-long-chain-polyunsaturated-fatty-acid (ω3-LCPUFA) correlate with a decreased risk of AMD. Dietary ω3-LCPUFA versus ω6-LCPUFA inhibits mouse ocular neovascularization, but the underlying mechanism needs further exploration. The aim of this study was to investigate if adiponectin (APN) mediated ω3-LCPUFA suppression of neovessels in AMD.

Methods

The mouse laser-induced choroidal neovascularization (CNV) model was used to mimic some of the inflammatory aspect of AMD. CNV was compared between wild-type (WT) and Apn^−/− mice fed either otherwise matched diets with 2% ω3 or 2% ω6-LCPUFAs. Vldlr^−/− mice were used to mimic some of the metabolic aspects of AMD. Choroid assay ex vivo and human retinal microvascular endothelial cell (HRMEC) proliferation assay in vitro was used to investigate the APN pathway in angiogenesis. Western blot for p-AMPKα/AMPKα and qPCR for Apn, Mmps, and IL-10 were used to define mechanism.

Results

ω3-LCPUFA intake suppressed laser-induced CNV in WT mice; suppression was abolished with APN deficiency. ω3-LCPUFA, mediated by APN, decreased mouse Mmps expression. APN deficiency decreased AMPKα phosphorylation in vivo and exacerbated choroid-sprouting ex vivo. APN pathway activation inhibited HRMEC proliferation and decreased Mmps. In Vldlr^−/− mice, ω3-LCPUFA increased retinal AdipoR1 and inhibited NV. ω3-LCPUFA decreased IL-10 but did not affect Mmps in Vldlr^−/− retinas.

Conclusions

APN in part mediated ω3-LCPUFA inhibition of neovascularization in two mouse models of AMD. Modulating the APN pathway in conjunction with a ω3-LCPUFA-enriched-diet may augment the beneficial effects of ω3-LCPUFA in AMD patients.

ω-3 and ω-6 long-chain PUFAs and their enzymatic metabolites in neovascular eye diseases

Neovascular eye diseases, including retinopathy of prematurity, diabetic retinopathy, and age-related macular degeneration, threaten the visual health of children and adults. Current treatment options, including anti-vascular endothelial growth factor therapy and laser retinal photocoagulation, have limitations and are associated with adverse effects; therefore, the identification of additional therapies is highly desirable. Both clinical and experimental studies show that dietary ω-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFAs) reduce retinal and choroidal angiogenesis. The ω-3 LC-PUFA metabolites from 2 groups of enzymes, cyclooxygenases and lipoxygenases, inhibit [and the ω-6 (n-6) LC-PUFA metabolites promote] inflammation and angiogenesis. However, both of the ω-3 and the ω-6 lipid products of cytochrome P450 oxidase 2C promote neovascularization in both the retina and choroid, which suggests that inhibition of this pathway might be beneficial. This review summarizes our current understanding of the roles of ω-3 and ω-6 LC-PUFAs and their enzymatic metabolites in neovascular eye diseases.

Inflammatory signals from photoreceptor modulate pathological retinal angiogenesis via c-Fos

Pathological neovessels growing into the normally avascular photoreceptors cause vision loss in many eye diseases, such as age-related macular degeneration and macular telangiectasia. Ocular neovascularization is strongly associated with inflammation, but the source of inflammatory signals and the mechanisms by which these signals regulate the disruption of avascular privilege in photoreceptors are unknown. In this study, we found that c-Fos, a master inflammatory regulator, was increased in photoreceptors in a model of pathological blood vessels invading photoreceptors: the very low-density lipoprotein receptor-deficient (Vldlr^-/- ) mouse. Increased c-Fos induced inflammatory cytokines interleukin 6 (IL-6) and tumor necrosis factor (TNF), leading to activation of signal transducer and activator of transcription 3 (STAT3) and increased TNFα-induced protein 3 (TNFAIP3) in Vldlr^-/- photoreceptors. IL-6 activated the STAT3/vascular endothelial growth factor A (VEGFA) pathway directly, and elevated TNFAIP3 suppressed SOCS3 (suppressor of cytokine signaling 3)-activated STAT3/VEGFA indirectly. Inhibition of c-Fos using photoreceptor-specific AAV (adeno-associated virus)-hRK (human rhodopsin kinase)-sh_c-fos or a chemical inhibitor substantially reduced the pathological neovascularization and rescued visual function in Vldlr^-/- mice. These findings suggested that the photoreceptor c-Fos controls blood vessel growth into the normally avascular photoreceptor layer through the inflammatory signal-induced STAT3/VEGFA pathway.

Sema3f Protects Against Subretinal Neovascularization In Vivo

Pathological neovascularization of the outer retina is the hallmark of neovascular age-related macular degeneration (nAMD). Building on our previous observations that semaphorin 3F (Sema3f) is expressed in the outer retina and demonstrates anti-angiogenic potential, we have investigated whether Sema3f can be used to protect against subretinal neovascularization in two mouse models. Both in the very low-density lipid-receptor knockout (Vldlr^−/−) model of spontaneous subretinal neovascularization as well as in the mouse model of laser-induced choroidal neovascularization (CNV), we found protective effects of Sema3f against the formation of pathologic neovascularization. In the Vldlr^−/− model, AAV-induced overexpression of Sema3f reduced the size of pathologic neovascularization by 56%. In the laser-induced CNV model, intravitreally injected Sema3f reduced pathologic neovascularization by 30%. Combined, these results provide the first evidence from two distinct in vivo models for a use of Sema3f in protecting the outer retina against subretinal neovascularization.

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Sema3f is expressed in the physiologically avascular layers of the outer retina.

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Vldlr^−/− mice have reduced Sema3f and form spontaneous subretinal neovascularization.

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AAV-mediated increase of Sema3f protects against neovascularization in Vldlr^−/− mice.

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Sema3f also reduces pathologic neovascularization in eyes with laser-induced CNV.

Abnormal formation of new blood vessels in the retina is one of the hallmarks of a potentially blinding eye disease called wet (or exudative) macular degeneration. Here we investigated in two independent mouse models whether Sema3f (a protein involved in guiding blood vessel growth) can be modulated to protect against abnormal blood vessel growth. In both mouse models, we found protective effects of Sema3f against abnormal blood vessel formation in the retina. Combined, these results provide the first evidence that Sema3f could be modulated to protect against wet macular degeneration.

IGF-1 in retinopathy of prematurity, a CNS neurovascular disease

The retina is part of the central nervous system and both the retina as well as the brain can suffer from severe damage after very preterm birth. Retinopathy of prematurity is one of the major causes of blindness in these children and brain neuronal impairments including cognitive defects, cerebral palsy and intraventricular hemorrhage (IVH) are also complications of very preterm birth. Insulin-like growth factor 1 (IGF-1) acts to promote proliferation, maturation, growth and survival of neural cells. Low levels of circulating IGF-1 are associated with ROP and defects in the IGF-1 gene are associated with CNS disorders including learning deficits and brain growth restriction. Treatment of preterm infants with recombinant IGF-1 may potentially prevent ROP and CNS disorders. This review compares the role of IGF-1 in ROP and CNS disorders. A recent phase 2 study showed a positive effect of IGF-1 on the severity of IVH but no effect on ROP. A phase 3 trial is planned.

Retinopathy of prematurity: the need for prevention

More than 450,000 babies are born prematurely in the USA every year. The improved survival of even the most vulnerable low body weight preterm infants has, despite improving health outcomes, led to the resurgence in preterm complications including one of the major causes for blindness in children, retinopathy of prematurity (ROP). The current mainstay in ROP therapy is laser photocoagulation and the injection of vascular endothelial growth factor (VEGF) antibodies in the late stages of the disease after the onset of neovascularization. Both are proven options for ophthalmologists to treat the severe forms of late ROP. However, laser photocoagulation destroys major parts of the retina, and the injection of VEGF antibodies, although rather simple to administer, may cause a systemic suppression of normal vascularization, which has not been studied in sufficient depth. However, the use of neither VEGF antibody nor laser treatment prevents ROP, which should be the long-term goal. It should be possible to prevent ROP by more closely mimicking the intrauterine environment after preterm birth. Such preventive measures include preventing the toxic postbirth influences (eg, oxygen excess) as well as providing the missing intrauterine factors (eg, insulin growth factor 1) and are likely to also reduce other complications of premature birth as well as ROP. This review is meant to summarize the current knowledge on the prevention of ROP with a particular emphasize on the use of insulin growth factor 1 supplementation.

Comparative evaluation of combined navigated laser photocoagulation and intravitreal ranibizumab in the treatment of diabetic macular edema

Objective

To evaluate if a standardized combination therapy regimen, utilizing 3 monthly ranibizumab injections followed by navigated laser photocoagulation, reduces the number of total ranibizumab injections required for treatment of diabetic macular edema (DME).

Research Design and Methods

A 12-month, prospective comparison of 66 patients with center-involving DME: 34 patients with combination therapy were compared to 32 patients treated with ranibizumab monotherapy. All patients initially received 3 monthly ranibizumab injections (loading phase) and additional injections pro re nata (PRN). Combination therapy patients additionally received navigated laser photocoagulation after the loading phase. Main outcome measures were mean number of injections after the loading phase and change in BCVA from baseline to month 12.

Results

Navigated laser combination therapy and ranibizumab monotherapy similarly improved mean BCVA letter score (+8.41 vs. +6.31 letters, p = 0.258). In the combination group significantly less injections were required after the 3 injection loading phase (0.88±1.23 vs. 3.88±2.32, p< = 0.001). By month 12, 84% of patients in the monotherapy group had required additional ranibizumab injections as compared to 35% in the combination group (p< = 0.001).

Conclusions

Navigated laser combination therapy demonstrated significant visual gains in most patients. Retreatment rate and number of injections were significantly lower compared to ranibizumab monotherapy and compared to the results of conventional laser combination therapy previously reported in pivotal anti-VEGF studies.

Scanning laser 'en face' retinal imaging of epiretinal membranes

PURPOSE

Comparison of scanning laser ophthalmoscopy (SLO) based 'en face' imaging techniques of patients with epiretinal membranes (ERM) and evaluation of the accuracy of preoperative diagnostic imaging.

METHODS

A consecutive, prospective series of 53 study eyes of 46 patients with clinically diagnosed and in optical coherence tomography (OCT) confirmed symptomatic ERMs were included in this study. Spectral domain (SD-) OCT volume scans (20° × 20° with 49 horizontal sections, ART 15) including SLO en face and fundus autofluorescence (FAF) images of the macula were obtained with HRA2 (Heidelberg Retina Angiograph-Optical Coherence Tomography, Heidelberg Engineering, Heidelberg, Germany). In addition, wide-field SLO color and FAF images (Optomap 200Tx, Optos PLC, Dunfermline, UK) were performed also covering the macular area. En face images of both devices were graded for each included study eye based on SD-OCT cross sectional scans.

RESULTS

Grading of SD-OCT (HRA2) based SLO en face green-blue enhanced multi-color, green reflectance, blue reflectance and standard multi-color visualization revealed a better detectability of ERM than SD-OCT-based en face infrared or FAF images or wide-field SLO (Optomap) based pseudo-color, red laser separation, green laser separation, or FAF images. Both FAF visualizations, HRA2 and Optomap based, achieved low mean scores. SD-OCT based en face thickness map visualization revealed good visualization but poor demarcation of epiretinal membranes.

CONCLUSIONS

In summary, en face regular or enhanced multicolor SLO images acquired with HRA2 allow a better visualization of epiretinal membranes for preoperative evaluation compared to SD-OCT based en face thickness map or pseudo-color images acquired with Optomap while infrared or FAF images are least suitable to depict epiretinal membranes.

EGFR-blockade with erlotinib reduces EGF and TGF-β2 expression and the actin-cytoskeleton which influences different aspects of cellular migration in lens epithelial cells

INTRODUCTION

After cataract surgery, residual lens epithelial cells migrate and proliferate within the capsular bag resulting in posterior capsule opacification (PCO). The up-regulation of TGF-β2, EGF and FGF-2 has been identified as a key factor in PCO pathogenesis leading to actin fiber assembly and alterations in the migration pattern. In this in vitro study, the influence of Erlotinib as a selective EGFR inhibitor is investigated on the cellular features indicated, which might promote a future clinical application.

METHODS

Expression of EGF, FGF-2 and TGF-β2 was measured using RT-PCR and ELISA in human lens epithelial cells (HLEC). Computational data of an in vitro time lapse microscopy assay were used for statistical analysis of single cell migration with a particular focus on cell-cell interaction; cell velocity distribution; and displacement before, during and after mitosis. The effect of Erlotinib on the actin-cytoskeleton was evaluated using Alexa Fluor 488 Phalloidin and epifluorescence microscopy.

RESULTS

EGF and TGF-β2 mRNA expression and protein levels are reduced by Erlotinib, while FGF-2 expression remained stable. Overall fluidity of cell-cell interaction is less in the presence of Erlotinib compared to the control and the velocity distribution across all cells becomes less uniform within the cell cluster. After mitosis, HLEC move significantly faster without EGFR inhibition, which can be completely blocked by Erlotinib. Furthermore, Erlotinib diminishes the amount of actin stress fibers and the stress fiber diameter.

CONCLUSION

As a novel effect of Erlotinib on HLEC, we describe the down-regulation of EGF and TGF-β2 expression, both are crucial factors for PCO development. Cellular movement displays complex alterations under EGFR inhibition, which is partly explained by actin fiber depletion. These findings further underline the role of Erlotinib in pharmacologic PCO prophylaxis.