Guidance for the treatment of neovascular age-related macular degeneration

Findings of uncertain significance by optical coherence tomography (OCT) as prognostic factors in neovascular age-related macular degeneration (nAMD) treated with ranibizumab

Background

Biomarkers hold great promise for personalized medicine as information gained from diagnostic or progression markers can be used to tailor treatment to the individual for highly effective intervention in the disease process.

Methods

The aim of this retrospective study was to evaluate the association between visual outcome and the presence of findings of uncertain significance by optical coherence tomography (OCT) pre and post loading dose in patients with neovascular age-related macular degeneration (nAMD) treated with ranibizumab.

Results

Univariate analysis revealed a higher letter gain in those with presence of onion sign (+ 5.6 ETDRS letters, p = 0.04) absence of prechoroidal cleft (+ 3.7 ETDRS letters, p = 0.04), intraretinal pseudocysts (+4.8 ETDRS letters, p = 0.002), subretinal pseudocysts (+ 4.6 ETDRS letters, p = 0.005) and choroidal caverns (+ 4.4 ETDRS, letters p = 0.0065).

Conclusions

The presence of prechoroidal cleft, intraretinal and subretinal pseudocysts and choroidal caverns were associated with lower visual gains. Moreover, we found that the onion sign is related as a biomarker of good prognostics.

Trial registration Registration number: 2021R13B2. Date of registration: 01/05/2020

Genotyping of Clinical Parameters in Age-Related Macular Degeneration

Background

Methods

Results

Conclusion

Atorvastatin-loaded solid lipid nanoparticles as eye drops: proposed treatment option for age-related macular degeneration (AMD)

Statins, widely prescribed for cardiovascular diseases, are also being eyed for management of age-related macular degeneration (AMD). Poor bioavailability and blood-aqueous barrier may however limit significant ocular concentration of statins following oral administration. We for the first time propose and investigate local application of atorvastatin (ATS; representative statin) loaded into solid lipid nanoparticles (SLNs), as self-administrable eye drops. Insolubility, instability, and high molecular weight > 500 of ATS, and ensuring that SLNs reach posterior eye were the challenges to be met. ATS-SLNs, developed (2339/DEL/2014) using suitable components, quality-by-design (QBD) approach, and scalable hot high-pressure homogenization, were characterized and evaluated comprehensively for ocular suitability. ATS-SLNs were 8 and 12 times more bioavailable (AUC) in aqueous and vitreous humor, respectively, than free ATS. Three-tier (in vitro, ex vivo, and in vivo) ocular safety, higher corneal flux (2.5-fold), and improved stability (13.62 times) including photostability of ATS on incorporation in ATS-SLNs were established. Autoclavability and aqueous nature are the other highlights of ATS-SLNs. Presence of intact fluorescein-labeled SLNs (F-SLNs) in internal eye tissues post–in vivo application as eye drops provides direct evidence of successful delivery. Perinuclear fluorescence in ARPE-19 cells confirms the effective uptake of F-SLNs. Prolonged residence, up to 7 h, was attributed to the mucus-penetrating nature of ATS-SLNs.

Age-related ocular conditions: Current treatments and role of cyclodextrin-based nanotherapies

Age-related eye disorders are chronic diseases that affect millions of people worldwide. They cause visual impairment and, in some cases, irreversible blindness. Drug targeting to the retina is still a challenge due to the difficulties with drug distribution, crossing eye barriers, and reaching intraocular tissues in an effective therapeutic concentration. Although intravitreal injections can directly deliver drugs to the posterior segment of the eye, it remains an invasive technique and leads to several side effects. Conventional formulations such as emulsions, suspensions, or ointments have been related to frequent instillation and inability to reach intraocular tissues. New drug delivery systems and medical devices have also been designed. Nevertheless, these treatments are not always effective and sometimes require the presence of a specialist for the administration of the dose. Therefore, treatments for age-related ocular diseases remain as one of the major unmet clinical needs to manage these widespread eye conditions. Nanotechnology may become the adequate tool for developing effective and non-invasive therapies suitable for self-administration. In this review, we discuss emerging therapeutic options based on nanoengineering of cyclodextrin nanocarriers for the treatment of age-related eye disorders, including their pathophysiology, pharmacological options, and feasibility of clinical translation.

Real-world data in retinal diseases treated with anti-vascular endothelial growth factor (anti-VEGF) therapy - a systematic approach to identify and characterize data sources

BACKGROUND

Real-world data (RWD) has been a valuable addition to the scientific literature regarding treatment pathways, clinical outcomes and characteristics of patients with retinal diseases in recent years. Registries, observational studies and patient databases are often used for real-world research. However, there is limited information for each data source on the design, consistency, data captured, limitations and usability for assessing research questions. Using a systematic approach, we identified RWD sources for patients with retinal diseases and assessed them for completeness of data relating to different outcomes.

METHODS

A systematic literature review was carried out to identify RWD sources for patients with retinal disease. Potentially relevant articles published between 2006 and 2016 were screened following electronic searches in Embase and MEDLINE. Congress and supplementary searches were undertaken to identify RWD sources that may not be referenced in full publications. For each data source, availability and quantity of data on baseline status, clinical outcomes, treatment and management, safety, and patient-reported and economic burden were assessed using a bespoke completeness assessment tool based on International Consortium for Health Outcomes Measurement guidelines for macular degeneration. Completeness of data for each area of interest in each data source was assessed and rated using a 'good-moderate-poor' rating system based on availability and quantity of available data. Each data source was then given an overall score based on its score for each of the 7 areas of interest.

RESULTS

A total of 128 RWD sources from 32 countries were identified. Of the identified sources, 64 sources from 16 countries of interest were analyzed. Most of these sources provided information on baseline status and clinical outcomes and treatment, but few collected data on economic and patient-reported burden. Of the RWD sources analyzed, 10 scored highly in the overall completeness assessment, collecting data on most or all of the areas of interest; these sources are considered to be robust data sources for performing ophthalmology real-world studies.

CONCLUSIONS

The study provides a comprehensive list of RWD sources for patients with retinal disease, many of which will be useful for conducting real-world studies in the field of ophthalmology.

The Different Facades of Retinal and Choroidal Endothelial Cells in Response to Hypoxia

Ocular angiogenic diseases, such as proliferative diabetic retinopathy and neovascular age-related macular degeneration, are associated with severe loss of vision. These pathologies originate from different vascular beds, retinal and choroidal microvasculatures, respectively. The activation of endothelial cells (EC) plays pivotal roles in angiogenesis, often triggered by oxygen deficiency. Hypoxia-inducible factors in ECs mediate the transcription of multiple angiogenic genes, including the canonical vascular endothelial growth factors. ECs show notable heterogeneity in function, structure, and disease, therefore the understanding of retinal/choroidal ECs (REC; CEC) biochemical and molecular responses to hypoxia may offer key insights into tissue-specific vascular targeting treatments. The aim of this review is to discuss the differences spanning between REC and CEC, with focus on their response to hypoxia, which could provide innovative and sustainable strategies for site specific targeting of ocular neovascularization.

The potential of spectral domain optical coherence tomography imaging based retinal biomarkers

Background

Biomarker”, a merged word of “biological marker”, refers to a broad subcategory of medical signs that objectively indicate the state of health, and well-being of an individual. Biomarkers hold great promise for personalized medicine as information gained from diagnostic or progression markers can be used to tailor treatment to the individual for highly effective intervention in the disease process. Optical coherence tomography (OCT) has proved useful in identifying various biomarkers in ocular and systemic diseases.

Main body

Spectral domain optical coherence tomography imaging-based biomarkers provide a valuable tool for detecting the earlier stages of the disease, tracking progression, and monitoring treatment response. The aim of this review article is to analyze various OCT based imaging biomarkers and their potential to be considered as surrogate endpoints for diabetic retinopathy, age related macular degeneration, retinitis pigmentosa and vitreomacular interface disorder. These OCT based surrogate markers have been classified as retinal structural alterations (macular central subfield thickness and cube average thickness); retinal ultrastructural alterations (disruption of external limiting membrane and ellipsoid zone, thinning of retinal nerve fiber layer and ganglion cell layer); intraretinal microangiopathic changes; choroidal surrogate endpoints; and vitreoretinal interface endpoints.

Conclusion

OCT technology is changing very quickly and throughout this review there are some of the multiple possibilities that OCT based imaging biomarkers will be more useful in the near future for diagnosis, prognosticating disease progression and as endpoint in clinical trials.

Treatment for neovascular age related macular degeneration: The state of the art

With the introduction in the clinical practice of drugs inhibiting vascular endothelial growth factor (VEGF) the visual outcomes of patients with neovascular age related macular degeneration (AMD) dramatically improved. Since 2006 repeated intravitreal injections of anti-VEGF became the standard of care for the treatment of neovascular AMD. This review provides an overview of available data form clinical trials supporting the use of anti-VEGF molecules for the treatment of this condition. Several questions remain open, in particular the regimen of treatment, the frequency of injection, the safety of the different drugs, and the poor response to the treatment in some cases. Therefore, new agents and alternative delivery are currently under evaluation.

A prospective, observational, open-label, multicentre study to investigate the daily treatment practice of ranibizumab in patients with neovascular age-related macular degeneration

PURPOSE

The HELIOS (Health Economics with Lucentis in Observational Settings) study was designed on request of the Dutch Health Authority for an observational study to assess the effectiveness and safety of ranibizumab for neovascular age-related macular degeneration (wet AMD) in daily practice.

METHODS

The HELIOS study was a 2-year prospective, observational, open-label, multicentre study involving 14 sites. Patients with wet AMD were enrolled and observed for a period of 24 months. The data were collected at baseline and at the visits closest around the time-points 3, 6, 12, 18 and 24 months after inclusion.

RESULTS

Treatment with ranibizumab resulted in prevention of vision loss. The mean ETDRS score increased from 45.1 letters at baseline to 48.5 letters at 24 months. This was achieved with a mean of 7.8 injections over 24 months. Stabilization of visual acuity was also reflected by the scores on the quality of life EQ-5D questionnaire, which did not significantly change over the study period. The more subjective EQ-VAS questionnaire showed an overall improvement. The VFQ-25 questionnaire was also mostly stable over time. After 24 months, 32.2% of the patients gained ≥1 letter and 17.1% gained >15 letters. Patients completing the loading phase were better responders, as demonstrated by increased long-term visual acuity. In addition, ranibizumab was well tolerated and had a safety profile commonly seen in routine clinical practice.

CONCLUSION

This study demonstrates that also in daily practice ranibizumab was effective in preventing vision loss over a period of 24 months. No new safety findings were identified.

Parafoveal contributions to retinal function during ranibizumab therapy for age-related macular degeneration

OBJECTIVE

The standard measure for the assessment of functional vision in the central retina is best corrected visual acuity (VA). Our aim was to investigate whether it is an advantage to include tests for functional changes in the near retinal periphery to monitor treatment effects in patients receiving multiple injections of anti-vascular endothelial growth factor (anti-VEGF) agents for advanced exudative age-related macular degeneration (AMD).

DESIGN

Prospective pilot study.

PARTICIPANTS

Our cohort consisted of 24 patients with exudative AMD (mean age ± SD: 77.46 ± 7.82 years) treated at an ophthalmology clinic.

METHODS

We compared data from standard functional measurements, VA-near, and contrast sensitivity (CS), with results from the macular mapping test (MMT) at 10% and 100% contrast. Measurements of retinal thickness by optical coherence tomography (OCT) were used to document the morphologic efficacy of the anti-VEGF agent. Tests were performed at baseline and 4 weeks after 3 monthly ranibizumab injections.

RESULTS

All 4 functional tests yielded successes (equal or better visual performance after treatment) in 79.2% to 83.3% of cases. Including test locations in the near periphery yielded the highest success rate in the MMT at 10% contrast. Values for VA-near and CS also improved in a majority of cases. OCT measurements of retinal thickness indicated that the agent was effective in the fovea and near periphery.

CONCLUSIONS

Our findings indicate that using the MMT adds information about functional changes in the near periphery of the retina and allows more sensitive assessment of treatment effects or disease progression without the high expense of other techniques.

Electroforming of implantable tubular magnetic microrobots for wireless ophthalmologic applications

Magnetic tubular implantable micro-robots are batch fabricated by electroforming. These microdevices can be used in targeted drug delivery and minimally invasive surgery for ophthalmologic applications. These tubular shapes are fitted into a 23-gauge needle enabling sutureless injections. Using a 5-degree-of-freedom magnetic manipulation system, the microimplants are conveniently maneuvered in biological environments. To increase their functionality, the tubes are coated with biocompatible films and can be successfully filled with drugs.

Guidelines for the management of neovascular age-related macular degeneration by the European Society of Retina Specialists (EURETINA)

Age-related macular degeneration (AMD) is still referred to as the leading cause of severe and irreversible visual loss world-wide. The disease has a profound effect on quality of life of affected individuals and represents a major socioeconomic challenge for societies due to the exponential increase in life expectancy and environmental risks. Advances in medical research have identified vascular endothelial growth factor (VEGF) as an important pathophysiological player in neovascular AMD and intraocular inhibition of VEGF as one of the most efficient therapies in medicine. The wide introduction of anti-VEGF therapy has led to an overwhelming improvement in the prognosis of patients affected by neovascular AMD, allowing recovery and maintenance of visual function in the vast majority of patients. However, the therapeutic benefit is accompanied by significant economic investments, unresolved medicolegal debates about the use of off-label substances and overwhelming problems in large population management. The burden of disease has turned into a burden of care with a dissociation of scientific advances and real-world clinical performance. Simultaneously, ground-breaking innovations in diagnostic technologies, such as optical coherence tomography, allows unprecedented high-resolution visualisation of disease morphology and provides a promising horizon for early disease detection and efficient therapeutic follow-up. However, definite conclusions from morphologic parameters are still lacking, and valid biomarkers have yet to be identified to provide a practical base for disease management. The European Society of Retina Specialists offers expert guidance for diagnostic and therapeutic management of neovascular AMD supporting healthcare givers and doctors in providing the best state-of-the-art care to their patients.

TRIAL REGISTRATION NUMBER

NCT01318941.

Functional and anatomical outcome of eyes with neovascular age-related macular degeneration treated with intravitreal ranibizumab following an exit strategy regimen

Aims

To assess the functional and morphological outcome of eyes with neovascular AMD treated with intravitreal ranbizumab following an exit strategy treatment regime.

Methods

The Bern treatment regime for neovascular AMD has a fixed injection schedule, even in the non-active stage of the disease. The regimen has been adapted from the PIER study treatment protocol. Eyes with non-active AMD will receive 4 injections in the first year, and 2 injections in the second year of follow-up before treatment stops. Patients that received ranibizumab for treatment and reached the exit criteria were identified, and charts were reviewed to assess functional and morphological outcome.

Results

Only 2.6% of all patients (15 out of 575 patients) reached the exit criteria. Mean change in best corrected ETDRS visual acuity (VA) was 4.5±16.9 letters when comparing baseline VA to 4 weeks after the last injection (p=0.32). OCT mean foveal thickness was significantly thinner after last treatment (247.9±43.0 µm) compared to baseline (332.5±83.1 µm, p=0.002). The mean total number of ranibizumab injections was 15.6±8.0, and the mean total treatment period was 40.9±18.3 months. Twenty percent of eyes had geographic atrophy present at baseline versus 46.6% at the end of treatment.

Conclusions

Even with a fixed treatment regime and a defined treatment exit strategy, only a small percentage of patients reach exit criteria. Retinal thickness has been significantly reduced by repeated intravitreal ranibizumab injections, and geographic atrophy became more frequent.

Evaluation of clinical and genetic indicators for the early response to intravitreal ranibizumab in exudative age-related macular degeneration

Aim: This study was conducted to evaluate the possible clinical and genetic indicators for an early response to intravitreal ranibizumab (IVR) in exudative age-related macular degeneration (AMD). Patients & methods: The records of 120 eyes from 120 Japanese patients with treatment-naive exudative AMD were retrospectively reviewed. Three consecutive IVR treatments were performed every month. Achievement of anatomical resolution was evaluated by ophthalmoscopy and optical coherence tomography. Multivariable logistic regression analysis was conducted by analyzing SNPs in the ARMS2 locus (A69S) and in the CFH gene (I62V and Y402H), in addition to clinical factors. Results: The mean central retinal thickness of overall patients was significantly decreased (-120.1 ± 122.8 µm, p = 2.7 × 10-19) at 3 months after the initial treatment. In the logistic regression analysis, the poor anatomical resolution of the lesion at 3 months was associated with the combination of CFH I62V + CFH Y402H variants (p = 0.0021), and the polypoidal choroidal vasculopathy lesions (p = 0.044). Conclusion: The CFH variants and the polypoidal choroidal vasculopathy lesion may influence the early anatomical resolution with IVR in exudative AMD.

Original submitted 30 September 2013; Revision submitted 13 March 2014

[Availability of resources for patients with wet age-related macular degeneration. Optimal study]

OBJECTIVE

The aim of the study was to assess the availability of resources for patients with wet age-related macular degeneration (wAMD) in current clinical practice.

METHODS

Observational, cross-sectional and multicenter study. Eligible subjects were ≥ 18 years old, with primary/secondary active subfoveal AMD-related choroidal neovascularization diagnosed 12-18 months prior to inclusion in the study.

RESULTS

A total of 266 patients were included (39 centers). The mean age (SD) was 76.1 (8.1) years, of whom 55.6% were female. According to the investigator assessment a median (Q1-Q3) of 20.0 (10.0-50.0) patients were visited weekly. A mean of 100.0 (45.0-250.0) were currently under treatment mainly performed in operating rooms (61.5%). Centers had 1.0 (1.0-2.0) operating rooms available for treatment 2.0 (2.0-5.0) days/week. In 74.4% they were located on different floors/buildings from ophthalmology services. Waiting time until visit was 40.0 (30.0-60.0) min, and duration of treatment was 20.0 (15.0-50.0) min. The time between request until medical visit was 20.0 (15.0-30.0) days, and from diagnosis to treatment was 7.0 (5.0-10.0) days. Clinicians considered there was insufficient staff for examinations (84.6%), and treatment (46.2%). About 30.8% and 20.5% mentioned lack of diagnostic tools, such as optical coherence tomography and fluorescein angiography.

CONCLUSIONS

More resources for diagnosis and treatment of wAMD are required. These results, together with the current policy of reducing the budget in the Spanish Health System, could lead to possible delays in the diagnosis and treatment of wAMD.

Effectiveness of intravitreal ranibizumab in exudative age-related macular degeneration (AMD): comparison between typical neovascular AMD and polypoidal choroidal vasculopathy over a 1 year follow-up

BACKGROUND

The effects of intravitreal ranibizumab (IVR) against exudative age-related macular degeneration (AMD) may be different associated with the lesion phenotype. This study was conducted to compare the outcomes of IVR between two different phenotypes of exudative AMD: typical neovascular AMD (tAMD) and polypoidal choroidal vasculopathy (PCV).

METHODS

This is a retrospective cohort study of 54 eyes from 54 subfoveal exudative AMD patients (tAMD 24, PCV 30 eyes). Three consecutive IVR treatments (0.5 mg) were performed every month, followed by re-injections as needed. Change in the best-corrected visual acuity (BCVA) and central retinal thickness (CRT) were then compared between the tAMD and PCV groups over 12 months of follow-up.

RESULTS

The mean BCVA was significantly improved (-0.11 logMAR units) at month 3 after the initial IVR (p <0 .001, Wilcoxon signed-rank test), and was sustained up to 12 months in all AMD patients (p =0.02). In the subgroup analysis, the tAMD group showed a significant improvement in their mean BCVA (-0.06, -0.17, -0.15 and -0.16 logMAR units at 1, 3, 6 and 12 months, respectively), but there was only a slight but non-significant improvement in the PCV group. The improvement in the BCVA was significantly greater in the tAMD group than in the PCV group (p = 0.043, repeated measures ANOVA) over 12 months. Both phenotypes showed significant improvements in the CRT during 12 months after the initial IVR.

CONCLUSIONS

IVR is an effective therapy for tAMD and PCV in the BCVA improvement in Japanese patients over 12 months of follow-up. The phenotype of tAMD showed a significantly better outcome with IVR than PCV in terms of BCVA improvement.

Is quantitative spectral-domain superior to time-domain optical coherence tomography (OCT) in eyes with age-related macular degeneration?

PURPOSE

The aim of this study was to determine the variability of macular map measurements, for two generations of optical coherence tomography (OCT) instruments, in eyes with wet age related macular degeneration (AMD) and low visual acuity.

METHODS

Patients were examined with Stratus OCT and Cirrus HD-OCT. The macular thickness was assessed with the 'macular thickness map scan' and 'fast protocol' in Stratus and with the 512 × 128 and 200 × 200 cube protocols in Cirrus OCT. Two measurements were taken one directly after the other, at the first visit to analyse repeatability. Approximately 1 week later, a third measurement was taken to analyse reproducibility. In Cirrus OCT, a manual correction of foveal location was also performed. Repeatability and reproducibility were calculated as a coefficient of variance (CoV) and a coefficient of repeatability/reproducibility.

RESULTS

 Repeatability for central macular thickness (expressed as CoV) was about three per cent for all protocols, and the coefficient of repeatability between 34 and 54 μm. Reproducibility (also expressed as CoV) was between four to seven per cent and coefficient of repeatability between 64 and 89 μm. After manual adjustment of foveal location in Cirrus OCT, the coefficient of repeatability improved to 12-18 μm, and the coefficient of reproducibility to 44-47 μm.

CONCLUSIONS

  In eyes affected by wet AMD, there were small differences in repeatability and reproducibility when comparing quantitative maps in Stratus and Cirrus OCT. However, when the software for manual correction of foveal position in Cirrus OCT was used, the variability decreased markedly, and the repeatability was close to what had been reported in normal eyes, demonstrating a significant, potential advantage of spectral-domain over time-domain OCT.

An experimental study of a modified dahuang zhechong pill on the--angiogenesis of RF/6A cells in vitro

OBJECTIVE

To investigate the effects of a modified Dahuang Zhechong Pill (MDZP) on the angiogenesis of rhesus choroid-retina endothelial (RF/6A) cells and its preliminary mechanism.

METHODS

A 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) method was used to assess the effect of a MDZP on RF/6A cell proliferation induced by vascular endothelial growth factor (VEGF). Transwell inserts were used to assess the effect of the MDZP on RF/6A cell migration. Matrigel was used to assess the effect of the MDZP on the tube formation of RF/ 6A cells. Western blotting and quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) were used to detect the protein and mRNA expression, respectively, of VEGF and matrix metalloproteinase-2 (MMP-2) in RF/6A cells treated with the MDZP.

RESULTS

RF/6A cell proliferation induced by VEGF was inhibited by 0.2 mg/mL MDZP. At 0, 12.5, 25 and 50 mg/mL MDZP, the number of cells that migrated through Transwell membranes was 73.33 +/- 4.51, 61.33 +/- 4.04, 28.67 +/- 6.66 and 17.67 +/- 4.16, respectively, and the number of tubes formed in Matrigel was 20.33 +/- 0.58, 13.33 +/- 1.53, 11.00 +/- 1.00 and 1.33 +/- 0.58, respectively. At 100 and 200 mg/mL MDZP, the protein and mRNA expression of VEGF and MMP-2 were inhibited in RF/6A cells. At 400 mg/mL MDZP, the expression of VEGF mRNA and MMP-2 protein were inhibited in RF/6A cells.

CONCLUSIONS

MDZP inhibits the angiogenesis of RF/6A cells via the suppression of proliferation, migration and tube formation of RF/6A cells. Inhibition of the protein and mRNA expression of VEGF and MMP-2 in RF/6A cells may be an important mechanism.

Retinal function and morphology in rabbit after intravitreal injection of VEGF inhibitors

PURPOSE/AIM

To explore changes in morphology and function in the rabbit retina after intravitreal high-dose injection of three commonly used VEGF inhibitors.

MATERIALS AND METHODS

Forty-eight rabbits of mixed strain (6 months of age, body weight ≈ 3 kg) were randomized into four groups (n = 12). They were examined with full-field electroretinography (ERG) and with multifocal electroretinography (mf ERG) prior to drug exposure. The rabbits were then injected intravitreally with bevacizumab, ranibizumab, pegaptanib, or with a balanced saline solution. The dose of VEGF inhibitor was chosen to achieve a vitreous concentration approximately three times higher than the one clinically used in the adult human eye. ERG was then performed 8 weeks postinjection, and mf ERG 9 weeks postinjection. After 9 weeks, the rabbits were sacrificed and the sectioned retina was studied. Immunohistochemical analysis was performed of rods, cones, rod bipolar cells, horizontal cells, and amacrine cells.

RESULTS

Rabbits injected with VEGF inhibitors all showed significantly lower amplitude of the dark-adapted b-wave rod-mediated response to dim light, compared to the rabbits injected with BSS. The a wave (reflecting photoreceptor function) in the response to single flash white light was however not affected. Immunohistochemistry revealed a significant reduction in PKC labeling of rod bipolar cells in pegaptanib and ranibizumab injected eyes whereas bevacizumab injected eyes displayed normal PKC labeling. No apparent morphological change was seen with markers for remaining retinal cells.

CONCLUSIONS

Our results indicate that the use of high-dose intravitreal VEGF inhibitors in the rabbit eye affects rod-mediated retinal function and PKC expression in rod bipolars cells for at least 9 weeks after drug administration. The three VEGF inhibitors influence the retina slightly differently. These results are important for the understanding of drug action and when devising therapeutical strategies in new areas such as retinopathy of prematurity where vitreous volume is significantly lower compared to the adult eye.

Role of vascular endothelial growth factor polymorphisms in the treatment success in patients with wet age-related macular degeneration

PURPOSE

Along with environmental risk factors such as smoking, hypertension, and atherosclerosis, genetic susceptibility is a primary contributor to the development and progression of exudative age-related macular degeneration (AMD). Vascular endothelial growth factor (VEGF) is a central angiogenic regulator and there has been general agreement now that it is an important trigger for the progression of exudative AMD. In the present study, we tested the hypothesis that VEGF gene polymorphisms play a role in the treatment success with VEGF inhibitors in patients with exudative AMD.

DESIGN

Prospective cohort study.

PARTICIPANTS

We included 185 eyes of 141 patients with exudative AMD who were scheduled for their first treatment with intravitreally administered bevacizumab in this trial.

METHODS

All patients were aged >50 years and had angiographically verified exudative AMD. Blood from the finger pad was collected on blood cards for genotyping for the VEGF polymorphisms rs1413711, rs3025039, rs2010963, rs833061, rs699947, rs3024997, and rs1005230. At each follow-up visit, visual acuity was reassessed and an ophthalmic examination was carried out. Visual acuity outcome, number of retreatments, and overall time of treatment were analyzed in dependence of the VEGF polymorphisms.

MAIN OUTCOME MEASURES

Mean change in visual acuity at the end of the treatment period.

RESULTS

The included patients were reinjected with bevacizumab 1 to 15 times, resulting in a total treatment period of 42 to 1182 days. In univariate analysis only the G/G genotypes of rs3024997 and rs2010963 compared with all other 5 single nucleotide polymorphisms (SNPs) showed a significantly lower visual acuity at the end of treatment. In multivariate analysis including parameters such as time, baseline visual acuity, and number of reinjections, none of the SNPs showed a significant correlation.

CONCLUSIONS

The current study indicates that VEGF polymorphisms are not major predictors of anti-VEGF treatment success in patients with exudative AMD.

Effectiveness of ranibizumab intravitreal injections for exudative age-related macular degeneration treatment: 12-month outcomes

Background

The aim of this paper was to evaluate functional and anatomical results of intravitreal ranibizumab injections and the course of exudative age-related macular degeneration (AMD) treatment over a 12-month observation period.

Material/Methods

In 25 patients with active dominantly classic exudative AMD, treatment was performed according to the following schedule: 3 intravitreal injections of 0.5 mg ranibizumab at monthly intervals (saturation phase); further injections were based on activity of the neovascular process. Changes in VA and central retinal thickness (CRT) during treatment were evaluated with ANOVA testing.

Results

Mean pre-treatment best corrected visual acuity was 0.73±0.27 logMAR. After the third ranibizumab injection the best results, 0.54±0.27 logMAR, were seen; 12-month results were 0.58±0.26 logMAR. Patients had a mean improvement of 10.6 letters at 12 months. In 92% of patients stabilization or improvement of vision was observed. The mean number of injections in the 12-month period was 6.

Baseline mean CRT was 351.12±74.15 μm. After the first ranibizumab injection it decreased significantly to 221.96±60.85 μm, after the third injection it was 200.80±47.63 μm, and after 12 months it was 213.16±44.37 μm. Mean correlations between baseline average CRT and baseline average VA measured in ETDRS letters (p=0.017) and in logMAR scale (p=0.033) and between average CRT after the third injection and average VA in logMAR scale after the third injection (p=0.047) were noted.

Conclusions

Treatment with intravitreal ranibizumab injections according to the presented scheme provides AMD patients with a chance of stabilization and improvement of the topical state, with a lower number of injections and preserved topical and general safety. Our results suggest that regular monthly controls are necessary to be able react rapidly to the smallest signs of deterioration, not only in visual acuity, but also in OCT images.

Intravitreal injection technique

As the intravitreal injection of therapeutic medication plays an increasingly large role in ophthalmology, its implementation continues to be modified and refined. Variations in injection technique are discussed, and the authors combine their clinical and research experience with a review of the literature to propose a recommended intravitreal injection protocol.

Early responses to intravitreal ranibizumab in typical neovascular age-related macular degeneration and polypoidal choroidal vasculopathy

Purpose. To evaluate the early response to intravitreal ranibizumab (IVR) in two different phenotypes of age-related macular degenerations (AMD): typical neovascular AMD (tAMD) and polypoidal choroidal vasculopathy (PCV). Methods. Sixty eyes from 60 patients (tAMD 28, PCV 32 eyes) were recruited. Three consecutive IVR treatments (0.5 mg) were performed every month. Change in the best-corrected visual acuity (BCVA) and central retinal thickness (CRT) was then compared between the tAMD and PCV groups. Results. The mean BCVA logMAR was significantly improved at month 1 and month 3 after the initial IVR in the tAMD group, but there was no change in the PCV group. Both phenotypes showed significant improvements in the CRT during the 3 months after the initial IVR. There were no significant differences in the improvements of the CRT in the tAMD versus the PCV group. In the stepwise analysis, a worse pretreatment BCVA and tAMD lesions were significantly beneficial for a greater improvement of BCVA at 3 months after the initial IVR. Conclusions. The phenotype of tAMD showed a significantly better early response to IVR than PCV in terms of BCVA improvement.

Severe decrease in visual acuity with choroidal hypoperfusion after photodynamic therapy

Background

Photodynamic therapy (PDT) is considered a selective method of treatment which works in areas of choroidal neovascularization (CNV); however, there are reports of choroidal hypoperfusion after PDT. This paper presents a clinical case of choroidal circulation disturbances caused by PDT, accompanied by CNV progression.

Case Report

The patient, a 75-year-old woman, was qualified for PDT in the right eye – first treatment due to progression of occult CNV. Best corrected visual acuity (BCVA) in the right eye at baseline was +0.3 logMAR. After PDT, a rapid decrease in visual acuity to +0.7 logMAR in the right eye was observed, central choroidal hypoperfusion in fluorescein angiography (FA) with subretinal fluid appeared and, as a consequence, progression of neovascular age-related macular degeneration (AMD). After stabilizing the local state through conservative therapy, a decision was made to treat the right eye with intravitreal injections of vascular endothelial growth factor (VEGF) inhibitor. During a 12-month period of observation, 7 doses of ranibizumab were administered. A regression in activity of wet AMD was observed, with visual acuity of +0.6 logMAR.

Conclusions

Choroidal circulation disturbance after PDT is possible and has to be taken into account. Sporadically, it can lead to an acute decrease in visual acuity and local state. After stabilization of AF and optical coherence tomography imaging, further treatment of neovascular AMD with intravitreal injections of anti-VEGF agents should be considered.

Changes in macular sensitivity after reduced fluence photodynamic therapy combined with intravitreal triamcinolone

PURPOSE

This study aimed to evaluate the course of macular sensitivity (MS) following treatment with reduced fluence photodynamic therapy (RPDT) versus standard photodynamic therapy (SPDT) in combination with intravitreal triamcinolone acetonide (IVTA) in patients with neovascular age-related macular degeneration, and to investigate the correlation between MS and angiographic outcomes.

METHODS

Forty eyes in 40 patients were included in this prospective, randomized clinical study. Group 1 patients received RPDT (n = 20, light dose of 25 J/cm(2) at 300 mW/cm(2)); group 2 patients received SPDT (n = 20, light dose of 50 J/cm(2) at 600 mW/cm(2)). All patients received 4 mg IVTA administered on the same day as RPDT or SPDT. Microperimetry, visual acuity testing (ETDRS) and fluorescein angiography (FA) were performed at baseline, and at months 3, 6, 9 and 12. Main outcome parameters were mean differential light threshold (DLT), and absolute and relative scotoma size.

RESULTS

Mean DLT decreased from 4.71 dB at baseline to 3.45 dB after 12 months in the SPDT + IVTA group (mean decrease 1.26 dB; p > 0.05) and from 5.42 dB to 4.92 dB in the RPDT + IVTA group (mean decrease 0.5 dB; p > 0.05). Absolute and relative scotoma sizes remained stable in both groups at 12 months (mean change 0 and -0.6 test-points; p > 0.05). Mean DLT values and absolute scotoma sizes correlated well with early and late leakage areas in FA (r = -0.45 to -0.80, p < 0.02).

CONCLUSIONS

With regard to MS, RPDT + IVTA did not show significant benefits over SPDT + IVTA at 12 months. Macular sensitivity correlated well with angiographic outcomes.

Patient characteristics and treatment of neovascular age-related macular degeneration in France: the LUEUR1 observational study

BACKGROUND

Age-related macular degeneration is the primary cause of blindness in developed countries. Current treatments of this degenerative disease mainly include laser, photodynamic therapy with verteporfin and administration of anti-vascular endothelial growth factors. The LUEUR (LUcentis® En Utilisation Réelle) study is composed of a cross-sectional part (LUEUR1), which examined the current management of wet AMD in France, and a follow-up part (LUEUR2), which will assess the development of patients treated for wet AMD over 4 years. Here we describe the results of LUEUR1.

METHODS

Patients with wet AMD were enrolled during a routine medical examination in LUEUR1, a cross-sectional, observational, prospective, multicentre study. Investigators recorded patient demographics, visual acuity, characteristics of wet AMD lesions, date of AMD diagnosis, comorbidities, previous treatments, treatments prescribed at inclusion, and low vision rehabilitation.

RESULTS

A total of 72 investigators recruited 1,019 patients with wet AMD, corresponding to 1,405 eyes affected by the disease. The mean age of patients was 78.7 ± 7.3 years. Most were female (62.3%) and non-smokers (66.9%). The mean visual acuity was 49.12 ± 24.18 Early Treatment Diabetic Retinopathy Study letters. Most eyes showed occult (52.8%) and subfoveal (84.6%) choroidal neovascularisation. Bilateral wet AMD affected 37.9% of patients. The median time since diagnosis was 12 months. Ranibizumab-based therapy (67.3%) and photodynamic therapy (29.8%) were the most frequent previous treatments. Prior to inclusion, 5.6% of patients had low vision rehabilitation. When a treatment was prescribed on the day of inclusion, it was most often ranibizumab (89.0% of all treatments at inclusion).

CONCLUSIONS

The results of this study illustrate the impact of anti-vascular endothelial growth factor therapies on the treatment of wet AMD in a real-life context. Specifically, ranibizumab-based therapy appears to have largely replaced laser photocoagulation and verteporfin-based photodynamic therapy.

Polypoidal choroidal vasculopathy masquerading as neovascular age-related macular degeneration refractory to ranibizumab

PURPOSE

To report a neovascular age-related macular degeneration pattern refractory to ranibizumab.

DESIGN

Retrospective, observational case series.

METHODS

Between March and May 2009, cases with neovascular age-related macular degeneration refractory to ranibizumab were investigated with indocyanine green angiography. We identified 12 eyes of 12 patients with polypoidal choroidal vasculopathy. Refractory to treatment were defined cases with persistent subretinal or intraretinal fluid, or both, after 3 or more consecutive monthly ranibizumab injections regardless of best-corrected visual acuity.

RESULTS

All patients identified were white, of whom 6 were male. Mean age ± standard deviation at presentation was 75 ± 5.6 years (range, 64 to 81 years); diagnosis, based on fluorescein angiography, comprised occult choroidal neovascularization (CNV) in 8 eyes, and 1 case each of classic-no-occult CNV, minimally classic CNV, predominantly classic CNV, and retinal angiomatous proliferation. Eight cases had switched from courses of other therapy (5 pegaptanib, 1 photodynamic therapy, 1 photodynamic therapy then pegaptanib, 1 bevacizumab). After a mean follow-up of 10.2 ± 4.8 months (range, 3 to 18 months) and 7.6 ± 3.9 ranibizumab injections (range, 3 to 14 injections), indocyanine green angiography revealed polypoidal choroidal vasculopathy lesions in all cases.

CONCLUSIONS

Neovascular age-related macular degeneration refractory to a course of ranibizumab injections may harbor polypoidal choroidal vasculopathy. In such cases, indocyanine green angiography is a valuable tool for revealing polypoidal lesions.

Clinical features and follow-up results of pulsating polypoidal choroidal vasculopathy treated with photodynamic therapy

PURPOSE

 To report on the clinical course of pulsating polypoidal choroidal vasculopathy (PCV) treated with photodynamic therapy (PDT).

METHODS

  A total of 63 eyes of 58 consecutive patients diagnosed with PCV, treated with PDT and followed up for at least 6months were enrolled. Best-corrected visual acuity (BCVA), fluorescein angiography and high-speed indocyanine green angiography (ICGA) using confocal scanning laser ophthalmoscopy (HRA) were performed.

RESULTS

  Of the 63 PCV eyes, 14 eyes (22.2%) of 14 patients were classified as having pulsating PCV. The mean age of pulsating PCV patients was 60.6±7.0years (48-69years), which was younger than non-pulsating PCV patients (65.7years, p=0.035). The mean follow-up period was 23.9±10.7months, and PDT was administered 1.6±0.9 times to pulsating PCV patients. The mean logMAR BCVAs were 0.85±0.47 at presentation and 0.71±0.52 at final examination. Extensive haemorrhagic events were more common in pulsating than in non-pulsating PCV patients (57.1% versus 26.5%, p=0.032). However, the risk of haemorrhage within 3months of PDT was similar for both pulsating PCV and the remaining patients (14.3% versus 20%, p=0.723).

CONCLUSION

  Pulsating PCV showed distinctive features including a relatively younger patient age at presentation, and a haemorrhagic tendency (especially extensive). However, the use of PDT did not directly increase the risk of haemorrhage in pulsating PCV patients.

Combined intravitreal bevacizumab and triamcinolone in exudative age-related macular degeneration

PURPOSE

We report on the combined application of intravitreal bevacizumab and triamcinolone acetonide for treatment of exudative age-related macular degeneration (AMD).

METHODS

 The clinical interventional case-series study included 16 patients (16 eyes) with exudative AMD who had previously received 3.5±1.8 mono-injections of bevacizumab (1.5mg) without significant improvement in visual acuity (VA) or reduction in macular exudation. All patients underwent a combined intravitreal injection of bevacizumab (1.5mg) and triamcinolone acetonide (about 20mg). Main outcome measures were VA and macular thickness as determined by optical coherence tomography. All patients were re-examined at 2-3months after the intervention.

RESULTS

Visual acuity improved significantly (p=0.03) from 0.80±0.40 logMAR prior to the combined injection to 0.65±0.42 logMAR at 3 months after the injection. An improvement of ≥1Snellen line was found in eight subjects, an increase of ≥2lines in five subjects, and an improvement of ≥3lines in two subjects. One patient lost 1line and one patient lost 3lines. Central retinal thickness decreased significantly from 272±62μm to 220±47μm (p=0.03). At the 6-month follow-up examination, central retinal thickness had increased again to 319±142μm, which was not significantly (p=0.30) different from baseline measurements.

CONCLUSIONS

The combined intravitreal application of bevacizumab and triamcinolone may temporarily be helpful in the treatment of exudative AMD if previous intravitreal bevacizumab mono-injections have failed to improve vision and reduce macular oedema.

Choroidal neovascularization associated with cancer-associated retinopathy

PURPOSE

To report an unusual association between cancer-associated retinopathy (CAR) associated with invasive thymoma and choriodal neovascularization (CNV), treated by photodynamic therapy (PDT).

METHODS

A 39-year-old man affected with thymoma and paraneoplastic syndrome (myasthenia gravis and diarrhoea) was observed between October 1997 and September 2007. The patient developed progressive visual dysfunction including bilateral visual acuity loss and concentric constriction of visual fields. Ophthalmological, immunological and systemic examinations were performed. Immunological evaluations included an assessment of antibody activity by indirect immunohistochemistry on sectioned rhesus monkey eye, and Western blot reactions upon an extract of pig retina.

RESULTS

Fundus ophthalmoscopy and fluorescein angiography revealed retinal vessel attenuation and retinal pigment epithelium degeneration. Electroretinogram suggested both rod and cone dysfunction. Indirect immunohistochemistry identified antibody activity within the photoreceptor outer segments. Western blots on the retina revealed that most of the patient's antibody activity was focused upon a retinal protein antigen approximating 145 kD. These findings share the commonalities of size and retinal distribution of the interphotoreceptor retinoid-binding protein (IRBP), a recognized autoantigen. The surgically resected mediastinal tumour was diagnosed as invasive thymoma. No other malignancy has since been found throughout nearly 10 years of follow-up. In March 2006, the patient developed a subfoveal CNV in his left eye, which was treated by PDT.

CONCLUSION

We describe the third case of paraneoplastic retinopathy associated with invasive thymoma. This is the first example of CAR involving autoantibodies reactive with a retinal protein having the characteristics of the IRBP, and is also the first complicated by CNV treated by PDT.

Significant improvements in near vision, reading speed, central visual field and related quality of life after ranibizumab treatment of wet age-related macular degeneration

PURPOSE

To investigate the effects on near visual acuity, reading speed, central visual field and related quality of life of ranibizumab treatment of wet age-related macular degeneration (AMD).

METHODS

The study was a prospective, non-comparative consecutive case series, followed for 3 months and investigator-driven. Thirty eyes of 30 patients with wet AMD were included, mean age 75 years (range 69-95 years). In addition to a full ophthalmological examination--including best-corrected visual acuity (BCVA; Early Treatment Diabetic Research Study chart), fundus biomicroscopy, fundus photography, fluorescein angiography, indocyanine green angiography (occult cases) and ocular coherence tomography--near visual acuity, reading speed, central visual field and quality of life for related activities were also investigated at baseline and at 3 months after ranibizumab treatment.

RESULTS

Mean BCVA increased from 62 +/- 11 to 66 +/- 14 letters at 3 months (7%; p = 0.018). Near vision improved from 9 +/- 5 to 6 +/- 3 points (33%; p = 0.0006) and reading speed increased from 59 +/- 40 to 85 +/- 50 words/min (44%; p < 0.0001). The mean deviation from normal of the visual field improved from -9 +/- 7 to -6 +/- 5 dB (33%; p < 0.0001). Quality of life improved for distance activities from 54 +/- 28 to 63 +/- 28 points (17%; p < 0.0001) but significantly (p = 0.024) more for near activities, from 49 +/- 26 to 63 +/- 26 points (29%; p < 0.0001). Reading newspaper text in the group in which the better eye was treated showed the highest increase in quality of life score of all: 116%.

CONCLUSION

The increase in BCVA after ranibizumab treatment is well established. The present study also showed significant improvements in other important visual qualities, such as near visual acuity, reading speed, central visual field and several activities influencing quality of life. The improvement was greater for near activities than for distance activities. Therefore, the beneficial effects of ranibizumab treatment shown here are more extensive than those reported previously.

Forecasting drug utilization and expenditure in a metropolitan health region

BACKGROUND

New pharmacological therapies are challenging the healthcare systems, and there is an increasing need to assess their therapeutic value in relation to existing alternatives as well as their potential budget impact. Consequently, new models to introduce drugs in healthcare are urgently needed. In the metropolitan health region of Stockholm, Sweden, a model has been developed including early warning (horizon scanning), forecasting of drug utilization and expenditure, critical drug evaluation as well as structured programs for the introduction and follow-up of new drugs. The aim of this paper is to present the forecasting model and the predicted growth in all therapeutic areas in 2010 and 2011.

METHODS

Linear regression analysis was applied to aggregate sales data on hospital sales and dispensed drugs in ambulatory care, including both reimbursed expenditure and patient co-payment. The linear regression was applied on each pharmacological group based on four observations 2006-2009, and the crude predictions estimated for the coming two years 2010-2011. The crude predictions were then adjusted for factors likely to increase or decrease future utilization and expenditure, such as patent expiries, new drugs to be launched or new guidelines from national bodies or the regional Drug and Therapeutics Committee. The assessment included a close collaboration with clinical, clinical pharmacological and pharmaceutical experts from the regional Drug and Therapeutics Committee.

RESULTS

The annual increase in total expenditure for prescription and hospital drugs was predicted to be 2.0% in 2010 and 4.0% in 2011. Expenditures will increase in most therapeutic areas, but most predominantly for antineoplastic and immune modulating agents as well as drugs for the nervous system, infectious diseases, and blood and blood-forming organs.

CONCLUSIONS

The utilisation and expenditure of drugs is difficult to forecast due to uncertainties about the rate of adoption of new medicines and various ongoing healthcare reforms and activities to improve the quality and efficiency of prescribing. Nevertheless, we believe our model will be valuable as an early warning system to start developing guidance for new drugs including systems to monitor their effectiveness, safety and cost-effectiveness in clinical practice.

Photodynamic therapy for chronic central serous chorioretinopathy

PURPOSE

This study aimed to evaluate the efficacy of photodynamic therapy (PDT) in treating chronic central serous chorioretinopathy (CSC).

METHODS

We describe a non-randomized, multicentre, interventional case series. A total of 82 eyes of 72 patients with chronic CSC were treated by conventional PDT. LogMAR best corrected visual acuity (BCVA) (ETDRS charts) and central foveal thickness (CFT) measured by optical coherence tomography before and after PDT, number of PDT treatments and complications were used as outcome indicators.

RESULTS

Mean follow-up was 12 +/- 10 months and mean age was 46 +/- 10 years. Mean logMAR BCVA changed from 0.53 (standard deviation [SD] 0.43) before PDT to 0.38 (SD 0.41) at 3 months and 0.48 (SD 0.50) at 6 months (p < 0.0001 and p = 0.007, respectively, Student's t-test for paired data). Mean BCVA at the end of follow-up was 0.37 (SD 0.45; p < 0.0001 from baseline). Macular detachment was resolved and subretinal fluid (SRF) disappeared in all cases. Central foveal thickness decreased from 325 microm (SD 95), to 229 microm (SD 70) at 1 month after PDT, 206 microm (SD 68) at 3 months, and 202 microm (SD 76) at 6 months (all p < 0.0001, Student's t-test for paired data). No cases developed severe visual loss or complications derived from PDT. Reactive retinal pigment epithelium hypertrophy appeared in nine cases after PDT.

CONCLUSIONS

Photodynamic therapy with verteporfin may be useful in chronic CSC for improving BCVA and reducing SRF and CFT. Randomized studies with longer follow-up are needed to assess the real role of this treatment in chronic CSC.

Clinical and histological findings after intravitreal injection of bevacizumab (Avastin) in a porcine model of choroidal neovascularization

PURPOSE

To examine the effect of intravitreally injected bevacizumab (Avastin) on the histological and angiographic morphology of choroidal neovascularization (CNV) in a masked and placebo-controlled animal study.

METHODS

Choroidal neovascularization was induced surgically in 11 porcine eyes by perforating Bruch's membrane with a retinal perforator. After closure of the ports used for the vitrectomy, which was performed to facilitate the Bruch's membrane rupture, 0.05 ml of either bevacizumab or Ringer-Lactat (placebo) was injected into the vitreous cavity. Eyes were enucleated after 14 days. Fundus photographs and fluorescein angiograms (FAs) were obtained immediately prior to enucleation. Sections of formalin- and paraffin-embedded eyes were examined by light microscopy and by immunohistochemical staining.

RESULTS

Placebo-injected eyes exhibited the highest propensity to leak, with five of six eyes leaking on FA, whereas only one of five bevacizumab-injected eyes exhibited leakage. On histological examination, all 11 eyes contained CNV membranes of similar size, regardless of treatment. The number of vascular endothelial cells was significantly reduced (p = 0.03) in CNV membranes from eyes that had been injected with bevacizumab when compared with CNV membranes from placebo-injected eyes. There was a trend towards more retinal pigment epithelium cells (p = 0.16) and fewer glial fibres (p = 0.08) in membranes from bevacizumab-treated eyes compared with placebo-treated eyes. Bevacizumab was identified immunohistochemically in the inner limiting membrane (ILM) and to a lesser degree in the remaining retina. Strong staining was also detected in both retinal blood vessels and entire CNV membranes with no cellular predisposition. Vascular endothelial growth factor expression was found in the CNV membranes, in the ILM, in the ganglion cell layer, in Müller cells throughout the neuroretina and in retinal blood vessels.

CONCLUSIONS

Bevacizumab significantly reduced the proliferation of vascular endothelial cells in CNV membranes and showed a strong trend towards a reduction of leakage from these membranes. After a single injection, bevacizumab did not exhibit a size reducing effect on CNV, but it was still present in the membranes 14 days after intravitreal injection.

Combination therapy using verteporfin and ranibizumab; optimizing the timing in the CAM model

Combining photodynamic therapy (PDT) using verteporfin (Visudyne) with ranibizumab (Lucentis) can optimize the overall treatment outcome by providing more efficacy in vessel closure, and thus reduce the need for retreatment in patients with wet age-related macular degeneration. In this preclinical study in the chorioallantoic membrane (CAM) of the chicken embryo, we compare the vascular occlusion effects of verteporfin and ranibizumab as monotherapies with those observed in the combined therapy. In order to optimize the combination therapy, we varied the timing and sequence of the PDT and antivascular endothelial growth factor modalities. We observed that 1 day after PDT, the smaller blood vessels (Ø < 70 microm) of the CAM were selectively occluded, but as early as 2 days after PDT, both significant reperfusion and regrowth of new vessels were observed. Both these phenomena could be significantly delayed by application of ranibizumab. Ranibizumab itself did not induce any vascular occlusion. Under the applied conditions of combination therapy, the occlusion of the targeted blood vessels could be significantly extended to 3 days in this model compared with 1 day in the case of verteporfin monotherapy. Thus, in the present preclinical study, we demonstrate that for the applied conditions, the optimal time to administer ranibizumab is 24 h after PDT.

The protective role of Visudyne eyeglass against VEGF synthesis after photodynamic therapy with verteporfin

PURPOSE

We aimed to determine the extent of protection provided by Visudyne eyeglass against vascular endothelial growth factor (VEGF) synthesis following photodynamic therapy (PDT).

METHODS

Three groups with 14 rabbits in each were established. These consisted of a control (dextrose infusion) group, an infusion (verteporfin infusion) group and an irradiation (verteporfin infusion + irradiation) group. One eye in each animal was closed with Visudyne eyeglass and the other by eyelid sutures. The rabbits were exposed to daylight for 30 mins at 2 and 48 hours after the infusion was administered. Half the animals in each group were killed on day 5. The remaining animals were killed on day 10. Levels of VEGF in homogenized retina and choroids were analysed with an ELISA (enzyme-linked immunosorbent assay).

RESULTS

Mean VEGF levels, in pg/mg protein, on days 5 and 10 in the control + glass, control + suture, infusion + glass, infusion + suture, irradiation + glass and irradiation + suture subgroups were, respectively: 1.69 +/- 0.67, 1.91 +/- 0.44; 1.75 +/- 0.69, 1.93 +/- 0.53; 2.30 +/- 0.77, 3.47 +/- 2.02; 1.90 +/- 1.00, 2.93 +/- 0.16; 4.39 +/- 2.74, 13.63 +/- 5.25; 3.38 +/- 1.05, 7.37 +/- 2.12. On day 10, VEGF levels were significantly higher in the infusion and irradiation groups compared with the control group (p < 0.05). There were no statistically significant differences between glass and suture samples on days 5 and 10 in the infusion group, or on day 5 in the irradiation group. However, on day 10, the mean VEGF level in eyes closed with Visudyne eyeglass in the irradiation group was significantly higher than in sutured eyes (p = 0.011).

CONCLUSIONS

Visudyne eyeglass offers full protection against VEGF increases caused by verteporfin infusion but is only partially protective in eyes exposed to sensitizing light.

Ocular haemodynamic changes after single treatment with photodynamic therapy assessed with non-invasive techniques

PURPOSE

To investigate in patients with neovascular age-related macular degeneration (ARMD) the changes in ocular perfusion caused by single treatment with photodynamic therapy (PDT) by different non-invasive methods; to evaluate correlations between relative changes of ocular haemodynamic parameters after PDT among each other and compared to morphological parameters; and to assess this in relation to early changes of visual acuity.

METHODS

STUDY POPULATION

17 consecutive patients with subfoveal choroidal neovascularization (CNV) caused by ARMD scheduled for PDT without previous PDT treatment (four patients with predominantly classic CNV and 13 patients with occult CNV).

OBSERVATION PROCEDURES

best-corrected visual acuity (before PDT, 6 and 8 weeks after PDT), fundus photography, fluorescein angiography, haemodynamic measurements with laser Doppler flowmetry (LDF), laser interferometry and ocular blood flow (OBF) tonometry (baseline and 1, 2, 6 and 8 weeks after treatment).

MAIN OUTCOME MEASURES

choroidal blood flow (CHBF), fundus pulsation amplitude (FPA), pulsatile ocular blood flow (POBF), visual acuity. Changes smaller than 20% were considered clinically irrelevant.

RESULTS

Ocular haemodynamic parameters did not change significantly in the follow-up period. Changes of haemodynamic parameters showed no correlation to treatment spot, morphological changes or visual acuity. Changes of visual acuity were comparable to results of earlier studies.

CONCLUSION

Single treatment with PDT did not modify ocular blood flow parameters above 20% as assessed with different non-invasive methods.

Effect of ranibizumab retreatment frequency on neurosensory retinal volume in neovascular amd

PURPOSE

To determine the characteristics of patients with neovascular age-related macular degeneration who show initial anatomic improvements on optical coherence tomography in response to treatment with ranibizumab, but who subsequently regress toward their anatomic baseline.

METHODS

Data from 50 consecutive patients, receiving ranibizumab therapy for neovascular age-related macular degeneration, were collected. Raw StratusOCT images were analyzed using custom software ("OCTOR"). Changes in volume of neurosensory retina at months 1, 3, and 6 were calculated. Baseline demographic and morphologic characteristics were compared.

RESULTS

Forty-two patients (84%) showed a reduction in total retinal volume 1 month after initial treatment with ranibizumab. Of the patients that initially showed a reduction, 16 (38%) maintained this reduction through month 6, whereas 26 patients (62%) demonstrated a subsequent increase in retinal volume. Patients who maintained a reduction in edema received 3.75 +/- 1.18 injections of ranibizumab versus 2.96 +/- 1.34 injections for patients who did not (P = 0.049). Regression of initial anatomic improvements was associated with worsening of visual acuity (r = 0.599, P = 0.002).

CONCLUSION

Patients receiving fewer injections of ranibizumab appeared less likely to maintain anatomic improvements achieved following commencement of ranibizumab therapy; regression of these improvements was associated with deterioration in visual acuity.