The Natural History and Prognosis of Neovascular Age-Related Macular Degeneration

Cystoid macular degeneration in exudative age-related macular degeneration

PURPOSE

To investigate the prevalence and clinical significance of cystoid macular degeneration in eyes that underwent intravitreal ranibizumab injections for exudative age-related macular degeneration.

DESIGN

Retrospective, interventional case series.

METHODS

We reviewed the charts of 56 consecutive patients (19 male, 37 female; mean age ± standard deviation, 80.81 ± 4.8 years) with exudative age-related macular degeneration who received the last intravitreal ranibizumab injection at least 6 months before and were judged to have a fibroatrophic scar without signs of progression by fluorescein angiography or spectral-domain optical coherence tomography. Main outcome measures were the estimated prevalence and clinical significance of cystoid macular degeneration.

RESULTS

Twenty-two eyes showed various combinations of degenerative pseudocysts, whereas 34 eyes did not show any pseudocysts. The 95% confidence interval for the prevalence estimate was 36.98% to 41.02%. Degenerative pseudocysts appeared square-shaped, did not change their overall appearance over time, and were located just below the internal limiting membrane in 11 eyes (50%), in the inner nuclear layer in 16 eyes (72.7%), in the outer nuclear layer in 8 eyes (36.3%), and in all the retinal layers in 6 eyes (27.2%). Best-corrected visual acuity improved in eyes with and without degenerative pseudocysts and decreased significantly in eyes with degenerative pseudocysts (P = .03). Mean central macular thickness decreased significantly (P < .001) to 324.1 μm and to 328.2 μm in eyes and without degenerative pseudocysts, respectively.

CONCLUSIONS

Cystoid macular degeneration represents a well-distinguished clinical entity that may be detected in exudative age-related macular degeneration eyes showing a posttreatment fibroatrophic scar and should not be considered as a manifestation of choroidal neovascularization activity.

Effects of subretinal electrical stimulation in mer-KO mice

PURPOSE

Subretinal electrical stimulation (SES) from microphotodiode arrays protects photoreceptors in the RCS rat model of retinitis pigmentosa. The authors examined whether mer(kd) mice, which share a Mertk mutation with RCS rats, showed similar neuroprotective effects from SES.

METHODS

Mer(kd) mice were implanted with a microphotodiode array at postnatal day (P) 14. Weekly electroretinograms (ERGs) followed by retinal histology at week 4 were compared with those of age-matched controls. RT-PCR for fibroblast growth factor beta (Fgf2), ciliary nerve trophic factor (Cntf), glial-derived neurotrophic factor (Gdnf), insulin growth factor 1 (Igf1), and glial fibrillary acidic protein (Gfap) was performed on retinas at 1 week after surgery. Rates of degeneration using ERG parameters were compared between mer(kd) mice and RCS rats from P28 to P42.

RESULTS

SES-treated mer(kd) mice showed no differences in ERG a- and b-wave amplitudes or photoreceptor numbers compared with controls. However, the expression of Fgf2 and Cntf was greater (6.5 ± 1.9- and 2.5 ± 0.5-fold, respectively; P < 0.02) in SES-treated mer(kd) retinas. Rates of degeneration were faster for dark-adapted maximal b-wave, log σ, and oscillatory potentials in mer(kd) mice than in RCS rats.

CONCLUSIONS

Although SES upregulated Fgf2 in mer(kd) retinas, as reported previously for RCS retinas, this was not accompanied by neuroprotection of photoreceptors. Comparisons of ERG responses from mer(kd) mice and RCS rats across different ages showed inner retinal dysfunction in mer(kd) mice but not in RCS rats. This inner retinal dysfunction and the faster rate of degeneration in mer(kd) mice may produce a retinal environment that is not responsive to neuroprotection from SES.

Clinical risk factors for age-related macular degeneration: a systematic review and meta-analysis

BACKGROUND

Age-related macular degeneration (AMD) is the leading cause of blindness in Western countries. Numerous risk factors have been reported but the evidence and strength of association is variable. We aimed to identify those risk factors with strong levels of evidence which could be easily assessed by physicians or ophthalmologists to implement preventive interventions or address current behaviours.

METHODS

A systematic review identified 18 prospective and cross-sectional studies and 6 case control studies involving 113,780 persons with 17,236 cases of late AMD that included an estimate of the association between late AMD and at least one of 16 pre-selected risk factors. Fixed-effects meta-analyses were conducted for each factor to combine odds ratio (OR) and/or relative risk (RR) outcomes across studies by study design. Overall raw point estimates of each risk factor and associated 95% confidence intervals (CI) were calculated.

RESULTS

Increasing age, current cigarette smoking, previous cataract surgery, and a family history of AMD showed strong and consistent associations with late AMD. Risk factors with moderate and consistent associations were higher body mass index, history of cardiovascular disease, hypertension, and higher plasma fibrinogen. Risk factors with weaker and inconsistent associations were gender, ethnicity, diabetes, iris colour, history of cerebrovascular disease, and serum total and HDL cholesterol and triglyceride levels.

CONCLUSIONS

Smoking, previous cataract surgery and a family history of AMD are consistent risk factors for AMD. Cardiovascular risk factors are also associated with AMD. Knowledge of these risk factors that may be easily assessed by physicians and general ophthalmologists may assist in identification and appropriate referral of persons at risk of AMD.

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.

As-Needed Treatment with Ranibizumab 0.5 mg in Patients with Neovascular Age-Related Macular Degeneration

Purpose

TO describe the results obtained in patients with neovascular age-related macular degeneration treated with ranibizumab 0.5 mg on an as-needed basis from the start after 1 year of follow-up.

Methods

Retrospective, consecutive interventional case series of patients with all angiographic types of neovascular age-related macular degeneration (mean baseline size, 3.4 disk areas) in a tertiary retinal center (Institut de la Màcula i la Retina; Barcelona, Spain). Main outcome was mean vision change; secondary outcomes were center retinal thickness change, number of injections, adverse events, and independent covariates associated with a good response.

Results

Mean visual acuity change was an increase of 1.3 letters (95% confidence interval −2.7 to +5.3), and difference between angiographic patterns did not reach statistical significance (p=0.30). A decrease in retinal thickness of 44.6 μm was identified (p<0.001), with a median of 3 injections. Absence of baseline arterial hypertension, lower visual acuity, and lesions located outside the fovea were associated with a better response to therapy.

Conclusions

As-needed treatment from the start achieved stabilization of visual acuity and a moderate decrease of retinal thickness with a low number of injections, but did not achieve the same efficacy as regular monthly injections.

Delay between medical indication to anti-VEGF treatment in age-related macular degeneration can result in a loss of visual acuity

BACKGROUND

Complicated approval procedures and limited short-term surgical capacities can result in time delays between the definition of a medical indication for ranibizumab treatment in active neovascular age-related macular degeneration (AMD) and the starting of treatment. This study aimed to evaluate changes in visual acuity and central retinal thickness over time, and their consequences for the patients concerned.

METHODS

Sixty-nine patients indicated for first-time ranibizumab treatment and 21 patients with necessary re-treatment were included in the study. Visual acuity and spectral domain optical coherence tomography (SD-OCT) central retinal thickness at the time of the indication examination were compared to values at the first-time treatment and during recurrent ranibizumab treatment.

RESULTS

For first-time treatment, the delay between indication and treatment was significantly higher for patients with vision loss compared to those without vision loss (31.6 ± 20.5 vs. 24.0 ± 8.3 days, p = 0.012). The increase in OCT central retinal thickness was 50.4 ± 92.8 μm for patients with vision loss compared to 5.1 ± 63.4 μm for those without vision loss, p = 0.029. A 1.1 logMAR line difference in vision loss was significant at p = 0.01 for patients with a delay in treatment of less than or equal to 28 days (48/69 patients, 69.7%) compared to those with a delay of more than 28 days (21/69 patients, 30.3%).

CONCLUSIONS

Even though average visual decay was slow at about one logMAR line over 110 days, individual patients (8.7%) experienced rapid loss of one or more lines within 21 days. Administrative procedures should therefore be expedited so that delays do not exceed 2 weeks for the sake of vision preservation in individual patients.

Combined vitreous and cataract surgeries in highly hyperopic eye

We report a case of a patient with a highly hyperopic eye who underwent cataract surgery combined with vitreous surgery to create a posterior vitreous detachment (PVD) to prevent choroidal neovascularization (CNV). A 78-year-old man noticed a decrease in his vision due to a cataract in his right eye. The patient had a severe visual loss in his left eye because of a CNV 2 years after a cataract surgery. His visual acuities were 20/30 OD and 20/600 OS, and funduscopic examination showed an orange-colored lesion OD and degenerative subretinal fibrosis OS. The posterior vitreous was attached to the retina in both eyes. The axial length was 18.9 mm OD and 19.0 mm OS. Cataract surgery combined with vitreous surgery to create PVD was performed on the right eye, and the vision improved to 20/20 with no signs of developing CNV after 5 years. We conclude that cataract surgery combined with vitreous surgery to create a PVD may prevent the development of CNV in highly hyperopic eyes.

Four-year incidence and progression of age-related macular degeneration: the Los Angeles Latino Eye Study

PURPOSE

To estimate 4-year incidence and progression of early and advanced age-related macular degeneration (AMD).

DESIGN

Population-based cohort study.

METHODS

A comprehensive ophthalmologic examination including stereoscopic fundus photography was performed on adult Latinos at baseline and follow-up. Photographs were graded using a modified Wisconsin Age-Related Maculopathy Grading System. For estimations of incidence and progression of AMD, the Age Related Eye Disease Study Scale was used. Main outcome measures are incidence and progression of early AMD (drusen type, drusen size, and retinal pigmentary abnormalities) and advanced AMD (exudative AMD and geographic atrophy).

RESULTS

A total of 4658 of 6100 subjects (76%) completed the follow-up examination. The 4-year incidence of early AMD was 7.5% (95% CI: 6.7, 8.4) and advanced AMD was 0.2% (95% CI: 0.1, 0.4). Progression of any AMD occurred in 9.2% (95% CI: 8.3, 10.1) of at-risk participants. Incidence and progression increased with age. Incidence of early AMD in the second eye (11.2%) was higher than incidence in the first eye (6.9%). Baseline presence of soft indistinct large drusen >or=250 microm in diameter was more likely to predict the 4-year incidence of pigmentary abnormalities, geographic atrophy, and exudative AMD than smaller or hard or soft distinct drusen.

CONCLUSIONS

Age-specific incidence and progression of AMD in Latinos are lower than in non-Hispanic whites. While incident early AMD is more often unilateral, the risk of its development in the second is higher than in the first eye. Older people and those with soft indistinct large drusen had a higher risk of developing advanced AMD compared to those who were younger and did not have soft indistinct large drusen.

Clinical safety of ranibizumab in age-related macular degeneration

IMPORTANCE OF THE FIELD

Clinical safety of pharmaceutical products in the elderly is vital because of their increased risk of cardiac and other adverse events.

AREAS COVERED IN THIS REVIEW

Search of the Medline database, including articles and abstracts from 1984 to 2009.

WHAT THE READER WILL GAIN

Knowledge of ocular and systemic risks: The rate of endophthalmitis was 0.05% per injection (MARINA) and <0.1% per injection (ANCHOR), rates confirmed in a retrospective analysis of 14,320 injections. Moderate increases in intraocular pressure were transient, and incidences of intraocular inflammation were rarely serious. Systemic arterial thromboembolic events occurred in 4.6 and 0% of ranibizumab-treated patients and in 3.8 and 0% of sham-treated patients in MARINA (2 years) and PIER (1 year), respectively. In SAILOR, there was a numerically higher rate of cerebrovascular stroke with 0.5 mg ranibizumab compared with 0.3 mg ranibizumab (1.2 vs 0.7%), which was a non-statistically significant trend in patients with a history of stroke.

TAKE HOME MESSAGE

Although further studies to investigate the risk of stroke with ranibizumab therapy are required, repeated intravitreal ranibizumab was well tolerated and not associated with clinically significant safety risks during up to 2 years of treatment.

Newly diagnosed exudative age-related macular degeneration treated with pegaptanib sodium monotherapy in US community-based practices: medical chart review study

Background

Studies have shown that early detection and treatment of neovascular age-related macular degeneration (NV-AMD) can delay vision loss and blindness. The objective of this study was to evaluate the efficacy/safety of intravitreal pegaptanib sodium monotherapy in treatment-naïve subjects with newly diagnosed NV-AMD and to gain insight into characteristics of lesions treated in community-based practices.

Methods

From seven private US practices, charts were retrospectively reviewed on 73 subjects with previously untreated subfoveal choroidal NV-AMD treated with their first dose of pegaptanib monotherapy on/after 4/1/2005 through 6/5/2006, receiving ≥4 treatments at 6-week intervals over 21 weeks. Primary endpoint: mean visual acuity (VA) change from baseline to month 6.

Results

75% of lesions were occult, and 82% were subfoveal. From baseline to month 6, mean VA change was -0.68 lines; 58% and 16% gained ≥0 and ≥3 lines of VA, and 70% were responders (<3 lines lost). In 35 subjects with early disease, 80% were responders with a mean gain of 0.46 lines.

Conclusion

Pegaptanib is effective in real-world patients with treatment-naïve NV-AMD in uncontrolled community-based retina practices.

Microglia in the mouse retina alter the structure and function of retinal pigmented epithelial cells: a potential cellular interaction relevant to AMD

BACKGROUND

Age-related macular degeneration (AMD) is a leading cause of legal blindness in the elderly in the industrialized word. While the immune system in the retina is likely to be important in AMD pathogenesis, the cell biology underlying the disease is incompletely understood. Clinical and basic science studies have implicated alterations in the retinal pigment epithelium (RPE) layer as a locus of early change. Also, retinal microglia, the resident immune cells of the retina, have been observed to translocate from their normal position in the inner retina to accumulate in the subretinal space close to the RPE layer in AMD eyes and in animal models of AMD.

METHODOLOGY/PRINCIPAL FINDINGS

In this study, we examined the effects of retinal microglia on RPE cells using 1) an in vitro model where activated retinal microglia are co-cultured with primary RPE cells, and 2) an in vivo mouse model where retinal microglia are transplanted into the subretinal space. We found that retinal microglia induced in RPE cells 1) changes in RPE structure and distribution, 2) increased expression and secretion of pro-inflammatory, chemotactic, and pro-angiogenic molecules, and 3) increased extent of in vivo choroidal neovascularization in the subretinal space.

CONCLUSIONS/SIGNIFICANCE

These findings share similarities with important pathological features found in AMD and suggest the relevance of microglia-RPE interactions in AMD pathogenesis. We speculate that the migration of retinal microglia into the subretinal space in early stages of the disease induces significant changes in RPE cells that perpetuate further microglial accumulation, increase inflammation in the outer retina, and fosters an environment conducive for the formation of neovascular changes responsible for much of vision loss in advanced AMD.

New paradigms in the treatment of wet AMD: the impact of anti-VEGF therapy

The incidence of age-related macular degeneration (AMD) in the United Kingdom is increasing with the ageing population. The wet form of this progressive and potentially blinding disease can develop very rapidly and lead to severe loss of central vision and reduction in quality of life, sometimes in just a matter of weeks. Recent advances in the treatment of wet AMD with the licensing of anti-vascular endothelial growth factor therapies, coupled with current guidance from the Scottish Medicines Consortium and the National Institute of Health and Clinical Excellence have led to a subsequent increase in workload at AMD clinics due to the increased number of patients now eligible for treatment. In addition, the Royal College of Ophthalmologists recommend a 2-week diagnosis to treatment schedule due to the aggressive nature of the disease. The role of the retinal specialist is thus changing, and business management skills are becoming increasingly necessary to obtain the necessary resources to implement the guidance. Through prior experience and formal external evaluation of services at Frimley Park and Harrogate District Hospitals, a number of critical success factors have been developed for optimising treatment pathways in efficient wet AMD clinics.

Age-related macular degeneration and risk of coronary heart disease and stroke: the Cardiovascular Health Study

PURPOSE

To examine the associations of age-related macular degeneration (AMD) with incident coronary heart disease (CHD) and stroke in the Cardiovascular Health Study.

DESIGN

Population-based prospective cohort study.

PARTICIPANTS

A total of 1786 white and African-American participants free of CHD or 2228 participants free of stroke, aged 69 to 97 years.

METHODS

AMD was evaluated from photographs taken in 1997 and 1998.

MAIN OUTCOME MEASURES

Incident CHD and stroke ascertained using standardized methods.

RESULTS

Of the 1786 persons free of CHD, 303 developed incident CHD over 7 years. Participants with early AMD (n = 277) had a higher cumulative incidence of CHD than participants without early AMD (25.8% vs. 18.9%, P = 0.001). By adjusting for age, gender, race, systolic and diastolic blood pressure, hypertension status, fasting glucose, triglyceride, low-density lipoprotein cholesterol, cigarette smoking, pack years of smoking, and C-reactive protein, the presence of early AMD was associated with an increased risk of incident CHD (hazard ratio 1.57; 95% confidence interval, 1.17-2.22). Late AMD (n = 25) was not associated with incident CHD (hazard ratio 0.78; 95% confidence interval, 0.25-2.48). Among 2228 persons at risk, 198 developed incident stroke; neither early nor late AMD was associated with incident stroke.

CONCLUSIONS

This study suggests persons with early AMD have a higher risk of CHD but not stroke in a population aged 69 to 97 years. This provides further support that AMD is associated with underlying systemic vascular disease.

Predictive role of C677T MTHFR polymorphism in variable efficacy of photodynamic therapy for neovascular age-related macular degeneration

Age-related macular degeneration (AMD) complicated by subfoveal choroidal neovascularization (CNV) is the leading cause of severe central blindness in developed countries. AMD-related CNVs are distinguishable in classic and occult subtypes, characterized by variable natural history and different responsiveness to therapeutic procedures. Combined and repeated use of photodynamic therapy with verteporfin (PDT-V) and antiangiogenic drugs represents the most promising strategy against neovascular AMD, but it is unavoidably associated with mounting health-resource utilization. Predictive correlations between peculiar coagulation-balance gene variants and different levels of post-PDT-V benefit have recently been documented in Caucasians with AMD-related CNVs. In particular, methylenetetrahydrofolate reductase C677T substitution, a common thrombophilic folate pathway genotypic polymorphism, influences a better CNV responsiveness to PDT-V in classic- but not in occult-CNV cases. These pharmacogenetic findings indicate the opportunities to optimize the eligibility criteria of PDT-V and/or to perform this intriguing therapy in a customized manner, for finally minimizing the socio-economic burden of neovascular AMD.

Economic implications of current age-related macular degeneration treatments

PURPOSE

To measure the cost versus benefit of age-related macular degeneration (AMD) treatment strategies, existing and proposed, in the postranibizumab era.

DESIGN

Cost-effectiveness model.

PARTICIPANTS

None.

METHODS

University with hospital-based practice modeling of clinical examination, imaging, and treatment schedules were constructed considering published protocols where available, or by estimating usual practices. Medicare-allowable reimbursement schedules for a hospital-based, south Florida practice in 2007 were used to calculate costs of treatment. The lines of vision saved were deduced from published reports or using identified assumptions. This information was used to calculate cost per lines saved and, using actuarial tables data, costs per line-year saved were calculated.

MAIN OUTCOME MEASURE

Cost ($US) per line-year.

RESULTS

Consensus control values of expected lines loss if untreated (natural history) were established from published reports (2.5 lines at 1 year; 3.5 at 2 years) and photodynamic therapy (2.0 lines at 1 year; 3.0 at 2 years) for use in calculating lines of vision saved in studies without untreated control groups. The cost per line-year for 1 year of treatment ranged from a low of $84 with as-needed bevacizumab to $766 for protocol-style use of ranibizumab. Combination treatment regimens yielded a range of $71 to $269. The pharmaceutical proportion of treatment costs is higher than professional or facility costs, ranging to 83% for protocol-style ranibizumab.

CONCLUSIONS

Pharmaceutical-based treatments of AMD have markedly improved visual outcomes, but also have escalated costs markedly. Treatment regimens involving as-needed dosing, alternate medications, and combination therapy may preserve benefit for substantially lower costs. Disparate safety profiles would require consideration in choosing treatment regimens. Cost-benefit issues must be considered in AMD treatment regimens.

Current status of anti-vascular endothelial growth factor therapy in Europe

Vascular endothelial growth factor (VEGF) is an important modulator of angiogenesis, and has been implicated in the pathology of a number of conditions, including age-related macular degeneration (AMD), diabetic retinopathy, and cancer. AMD is a progressive disease of the macula and the third major cause of blindness worldwide. If not treated appropriately, AMD can progress rapidly, causing legal blindness within months of the second eye becoming affected. Until recently, the treatment options for AMD have been limited, with photodynamic therapy (PDT) the mainstay treatment. Although PDT is effective at slowing disease progression, it rarely results in improved vision. Pegaptanib and ranibizumab are both anti-VEGF therapies licensed for the treatment of neovascular AMD in Europe; however, these drugs are not yet available in Japan. This article reviews the available clinical data on anti-VEGF therapies for the treatment of neovascular AMD in Europe, and considers the future of this exciting therapy.

The role of the ERG in the diagnosis and treatment of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is affecting an increasing number of people, with 2.95 million people estimated to be affected in the USA by 2020. Possible preventive agents, such as vitamins and supplements have been studied and new treatment options for AMD have been developed in recent years. What role does electrophysiology play as a sensitive outcome measure? The most commonly used tests are the full-field electroretinogram (ffERG) and the multifocal ERG (mfERG). Test results from patients with AMD and reduced central vision need special attention in respect to fixation pattern, age-matched control data, and retinal luminance. Advantages, disadvantages and limitations of techniques will be considered, together with a review of published studies.

[Therapeutic modalities of age-related macular degeneration]

Age-related macular degeneration has become a leading cause of legal blindness in the industrial countries. Some hundred thousands of people are estimated to be suffering from the disease in Hungary as well. Earlier the different forms were considered as distinct diseases. Since the whole scale and pathomechanism of age-related macular degeneration has been clarified, and at the same time the therapeutic modalities have been developed in a lot of cases, there is good chance of maintaining or even improving visual acuity. The author describes the different forms of the disease, and then writes about the treatment modalities which proved to be effective, or which have been introduced recently in detail. He emphasises the harmful role of smoking among prevention methods. Conservative treatment beside antioxidants includes the so-called metabolic therapy nowadays. Different types of laser treatment are widely used, while irradiation to a smaller extent. The role of traditional surgical intervention is also limited, but the use of anti-vascular endothelial growth factors is very promising. Costs of different methods are also referred to.