Quantitative assessment of the long-term effect of photodynamic therapy in patients with pathologic myopia

Recent Advances in Photodynamic Therapy for Vascular Abnormalities

Background: Photodynamic therapy (PDT) is a minimally invasive therapy that was gradually established as a first-line treatment for vascular abnormalities. Its action depends on the appropriate wavelength of light and photosensitizer to produce toxic oxygen species and cause cell death. Objective: Several new clinical improvements and trends in PDT have been described in recent years. The aim of this review is to provide an overview of the current data from clinical trials. Methods: In this review, we introduce and generalize the wavelength, duration, dose, strength, and photosensitizer of PDT for the treatment of vascular abnormalities, such as circumscribed choroidal hemangiomas (CCH), choroidal neovascularization (CNV) and capillary malformation (CM). Results: The systematic review findings indicate that the application of PDT is a safe effective method to treat CCH, CNV and CM. However, PDT also has early onset side effects and late onset side effects. Conclusions: Based on the discussion of the effectiveness of PDT, we conclude that PDT has great potential for clinical use, although PDT has possible side effects.

Chorioretinal Atrophic Lesions Evolution in Patients with Quiescent Myopic Choroidal Neovascularization Followed for More Than 10 Years

Purpose

To evaluate the progression of chorioretinal atrophic areas associated with myopic choroidal neovascularization (CNV) in high myopic patients followed by a minimum period of 10 years.

Patients and Methods

Patients with myopic CNV lesions that achieved clinical and structural remissions over 10 years of follow-up were included. Medical records were reviewed for CNV characterization and treatment, best-corrected visual acuity at baseline (BCVA0), immediately after the last treatment (BCVA1) and at the latest visit (BCVA2). Fundus autofluorescence (FAF) was used to quantify the amount of atrophic area increase per year associated with the treated myopic CNV lesion. The first FAF performed after treatment suspension (FAF1) was compared with the most recent exam (FAF2).

Results

Thirty-six eyes from 36 patients were included. Mean total follow-up was 12.38 ± 2.68 years. Mean number of intravitreal injections (IVI) was 12.50 ± 12.40 and 25% of the eyes had previous treatment with photodynamic therapy (PDT). Mean improvement between BCVA0 and BCVA1 was 5.58 ± 15.98 letters (p < 0.001). However, a drop of 8.03 ± 12.25 letters was noticed between BCVA1 and BCVA2. FAF1 was 6.34 ± 4.92mm2 and increased to 9.88 ± 7.56mm2 (3.54 ± 3.79mm2 variation p < 0.001). The mean growth rate of the atrophic area was 0.89 ± 0.84mm2 per year. BCVA2 negatively correlated with FAF2 (k = -0.498, p = 0.002) being worse in patients with higher atrophic area growth rate (k = -0.341, p = 0.042). Eyes treated with PDT needed less IVI (5.89 ± 5.21 vs 14.70 ± 13.36, p = 0.008) but had larger FAF1 (9.80 ± 5.33 vs 5.19 ± 4.27, p = 0.013) and FAF2 (16.05 ± 7.10 vs 7.83 ± 6.63, p = 0.003). Hypothyroidism was associated with higher atrophy growth rate (1.55 ± 1.15 vs 0.73 ± 0.67, p = 0.016).

Conclusion

This research demonstrates the importance of chorioretinal atrophy progression after myopic CNV lesions regression and its impact on visual prognosis, reporting a mean yearly growth of 0.89 mm2 in atrophic areas. Previous treatment with PDT and hypothyroidism were identified as risk factors associated with larger atrophic areas and worse visual outcomes.

Myopic macular diseases: A review

Recent evidence has demonstrated that the global public health burden of myopia is rising rapidly. Highly myopic eyes are associated with increased frequency of eye disorders that can lead to irreversible visual impairment. With recent technological advancement in ophthalmic imaging modalities, various macular complications associated with pathologic myopia are being elucidated. The development and progression of myopic chorioretinal atrophy, myopic macular neovascularization, myopic traction maculopathy and dome-shaped macula are vision-threatening myopic macular diseases. In order to overcome the challenges in managing patients with pathologic myopia, it is important to have a complete understanding in the natural course of these myopic macular diseases. Standardising the classification criteria of pathologic myopia is essential for enhancing clinical surveillance. Personalised pharmaceutical therapy and surgical interventions will help to optimise the treatment outcomes in patients suffering from these myopic macular diseases.

A systematic review of clinical practice guidelines for myopic macular degeneration

Background

Myopic macular degeneration (MMD) is a primary cause of blindness and visual impairment in many parts of the world. A review of clinical practice guidelines (CPGs) for intervention selection are required with the increasing demand for MMD management in clinical practice as well as in national health services. Therefore, we aim to systematically review CPGs for MMD and assist the recommendations development of the Package of Eye Care Interventions (PECI) program of the World Health Organization.

Methods

A systematic review of CPGs published on MMD between 2010 and April 2020 was conducted. Guidelines were evaluated using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool. Cochrane systematic reviews were also included when the evidence from included CPGs were inadequate or contradict.

Results

After applying exclusion criteria and conducting the quality appraisal, two CPGs were finally included. The average of the AGREE II ratings for the identified Guidelines were 56 and 63 respectively (7 for each item). To provide further information on interventions for MMD, one Cochrane review on MMD was additionally identified and included in the study. Intravitreal anti-vascular endothelial growth factor (anti-VEGF) drugs were recommended for patients with myopic choroidal neovascularization (mCNV) as first-line therapy to improve vision and reduce central macular thickness, and ranibizumab showed significant effectiveness compared to photodynamic therapy (PDT). PDT was recommended to be performed in those resistant to the treatment by one CPG but lacked of adequate description and support. Data extracted from the Cochrane systematic reviews indicated that anti-VEGF therapy for mCNV had significant effectiveness in improving visual acuity and reducing CMT compared to PDT with moderate to low certainty of evidence. Ranibizumab and bevacizumab were considered as equally effective with moderate certainty.

Conclusions

The outcomes of this review suggest that high quality clinical practice guidelines for MMD management are limited. Intravitreal injection of anti-VEGF agents was recommended as an effective intervention to treat myopic CNV as the first-line treatment, while there was inadequate guidance for the application of PDT in myopic CNV management. The use of other interventions for MMD were not recommended at this time and additional evidence is called for.

Anti-vascular endothelial growth factor therapy for the treatment of myopic choroidal neovascularization

Myopic choroidal neovascularization (CNV) is a sight-threatening condition which occurs in eyes with myopia, particularly in those with pathologic myopia. It is the most common cause of CNV among patients younger than 50 years. Hemorrhage and exudation from the CNV lesion may eventually result in scarring or chorioretinal atrophy. While myopic CNV was previously treated with focal laser photocoagulation or photodynamic therapy (PDT), the current treatment of choice is anti-vascular endothelial growth factor (VEGF) agents. Many studies have demonstrated the efficacy of intravitreal anti-VEGF agents in the treatment of myopic CNV. The RADIANCE study reported that intravitreal ranibizumab was superior to PDT in eyes with myopic CNV (at 3 months, both groups receiving intravitreal ranibizumab gained 10.5 and 10.6 letters vs 2.2 letters among patients receiving PDT). In addition, the study demonstrated similar visual outcomes in eyes treated on the basis of visual acuity stabilization or disease activity criteria. Other clinical studies have provided evidence for the efficacy of ranibizumab and aflibercept in the treatment of myopic CNV. This review addresses the epidemiology, pathophysiology, and imaging characteristics of myopic CNV, and discusses the evidence for the efficacy of anti-VEGF agents as compared to laser photocoagulation and PDT.

The role of anti-VEGF agents in myopic choroidal neovascularization: Current standards and future outlook

INTRODUCTION

The global prevalence of pathologic myopia is 0.9-3.1%, and visual impairment is found in 0.1-0.5% of European and 0.2-1.4% of Asian studies. Myopic choroidal neovascularization (mCNV) affects 5.2-11.3% of pathologic myopia patients and is a leading cause of vision impairment in the working-age population. Characteristic morphological changes and visual-acuity decrease are diagnostic features. Vascular-Endothelial-Growth-Factor (VEGF) has been identified as a trigger for pathologic neovascularization in these highly myopic patients.

AREAS COVERED

We cover the epidemiology, pathology and diagnostic aspects of mCNV. The history of therapeutic interventions is described, followed by an overview of current standard-of-care (SOC)-blocking VEGF using bevacizumab (off-label), ranibizumab or aflibercept and improving vision up to 13.5-14.4 letters. Despite good efficacy, an unmet medical need remains. We summarize ongoing and future developments of new drugs to treat or potentially cure mCNV.

EXPERT OPINION

mCNV is a major global health concern. Early detection and treatment is key for a satisfying outcome. The current SOC, VEGF inhibitors, affords good therapeutic efficacy and reasonable disease stabilization with few intravitreal treatments per year. However, the long-term prognosis is still unsatisfactory, and side-effects like chorioretinal atrophy development are of concern. Therefore, efforts should be intensified to develop more effective therapies.

Anti-VEGF treatment for myopic choroid neovascularization: from molecular characterization to update on clinical application

Choroidal neovascularization (CNV) secondary to pathologic myopia has a very high incidence in global, especially in Asian, populations. It is a common cause of irreversible central vision loss, and severely affects the quality of life in the patients with pathologic myopia. The traditional therapeutic modalities for CNV secondary to pathologic myopia include thermal laser photocoagulation, surgical management, transpupillary thermotherapy, and photodynamic therapy with verteporfin. However, the long-term outcomes of these modalities are disappointing. Recently, intravitreal administration of anti-VEGF biological agents, including bevacizumab, ranibizumab, pegaptanib, aflibercept, and conbercept, has demonstrated promising outcomes for this ocular disease. The anti-VEGF regimens are more effective on improving visual acuity, reducing central fundus thickness and central retina thickness than the traditional modalities. These anti-VEGF agents thus hold the potential to become the first-line medicine for treatment of CNV secondary to pathologic myopia. This review follows the trend of “from bench to bedside”, initially discussing the pathogenesis of myopic CNV, delineating the molecular structures and mechanisms of action of the currently available anti-VEGF drugs, and then systematically comparing the up to date clinical applications as well as the efficacy and safety of the anti-VEGF drugs to the CNV secondary to pathologic myopia.

Clinical characteristics and antivascular endothelial growth factor effect of choroidal neovascularization in younger patients in Taiwan

Background/Purpose:

The purpose of this study is to share experiences diagnosing and treating choroidal neovascularization (CNV) in young patients (age ≤ 50 years) at our hospital.

Methods:

The study reviewed retrospective data of patients (≤ 50 years old) with CNV who received antivascular endothelial growth factor treatment (anti-VEGF) between January 2007 and August 2012 at Shin Kong Wu Ho-Su Memorial Hospital. We recorded the total number of injections, types of drugs, preoperative and final best-corrected visual acuity (BCVA), central retinal thickness (CRT) in optical coherence tomography (OCT), and total follow-up times, and then used two-tailed paired t tests to compare mean changes in BCVA and CRT on OCT.

Results:

The study enrolled 59 patients ≤ 50 years of age with CNV diagnosed in 67 eyes. The mean age was 36.9 ± 10.0 years (range, 8–50 years). Twenty-one patients were male and 38 patients were female. Forty-two CNV lesions were subfoveal, 19 were juxtafoveal, and five were extrafoveal. The mean total follow-up time was 18.5 ± 19.9 months (range, 0.5–71 months). Pathologic myopia was the most common cause of CNV in this study (47.8%), followed by punctate inner choroidopathy (17.9%), idiopathic CNV (16.4%), polypoidal choroidal vasculopathy (13.4%), angioid streaks (3.0%), and choroidal rupture (1.5%). After anti-VEGF treatment, the mean BCVA improved from 0.69 ± 0.61 to 0.42 ± 0.59 (p < 0.05). CRT decreased from 257.5 ± 48.2 to 210.3 ± 35.7 (p < 0.05). The mean number of injections was 1.9 ± 1.6 (range, 1–9).

Conclusion:

In this study we found that pathologic myopia, punctate inner choroidopathy, and idiopathic and polypoidal choroidal vasculopathy comprised the four most common causes of CNV in patients ≤ 50 years of age in Taiwan. We also revealed that anti-VEGF treatment is highly effective in the treatment of CNV in this age group.

Myopic choroidal neovascularisation: current concepts and update on clinical management

Choroidal neovascularisation (CNV) is a common vision-threatening complication of myopia and pathological myopia. Despite significant advances in understanding the epidemiology, pathogenesis and natural history of myopic CNV, there is no standard definition of myopic CNV and its relationship to axial length and other myopic degenerative changes. Several treatments are available to ophthalmologists, but with the advent of new therapies there is a need for further consensus and clinical management recommendations. Verteporfin photodynamic therapy has been an established treatment for subfoveal myopic CNV for many years, but this treatment does not restore visual acuity and is associated with long-term chorioretinal atrophy. More recently, clinical trials investigating the efficacy and safety of anti-vascular endothelial growth factor agents in patients with myopic CNV have demonstrated substantial visual acuity gains and quality of life increases compared with photodynamic therapy. These enhanced outcomes provide updated evidence-based clinical management guidelines of myopic CNV, and increase the need for a generally accepted definition for myopic CNV. This review critically summarises the latest myopic CNV literature in the context of clinical experience and recommends a myopic CNV treatment algorithm.

Management of Choroidal Neovascularization Secondary to Pathological Myopia: The Era of Changes

Choroidal neovascularization (CNV) secondary to pathological myopia is an important cause of significant visual impairment in young adults. High myopia is particularly prevalent in Asian population. New scientific contributions have been made to the understanding of high myopia and myopic CNV. Treatment for myopic CNV has previously relied on photodynamic therapy, laser photocoagulation, and submacular surgery. The treatment outcomes from these modalities are, however, controversial. The introduction of antiangiogenic agents including bevacizumab and ranibizumab has brought the treatment of myopic CNV into a new era. The purpose of this review was to provide an overview of the natural history of myopic CNV, the prognostic factors, and the various treatment options including laser photocoagulation and photodynamic therapy, with particular attention on antiangiogenic agents.

Choroidal neovascularization in pathological myopia

Myopic choroidal neovascularization (CNV) is one of the leading causes of visual impairment worldwide. The clinical and socioeconomic impact of myopic CNV in Asian countries is particularly significant due to rising trend in the prevalence and severity of pathological myopia. The exact pathogenesis of myopic CNV remains unclear and there is paucity of information with respect to incidence and risk factors for myopic CNV from prospective studies. Furthermore, there are no recognized measures that may prevent or delay the development of CNV in eyes with pathological myopia. Advances have been made in the diagnosis and characterization of myopic CNV over the years. Until recently, treatment modalities for myopic CNV were limited to thermal laser photocoagulation and photodynamic therapy with verteporfin, both these modalities primarily aim at prevention of further visual loss. In the last 5 years, inhibitors of vascular endothelial growth factor (VEGF) have been used successfully and may improve vision to some extent. Nevertheless, the long-term safety and efficacy of anti-VEGF agents remains unknown. Furthermore, the risk of developing chorioretinal atrophy remains the key factor in determining the final visual outcome. This review article summarizes the current literature on myopic CNV, highlighting new evolving diagnostic and treatment modalities, prognostic factors influencing visual outcome, and areas of future research.

Anti-vascular endothelial growth factor for myopic choroidal neovascularization

Myopic choroidal neovascularization (CNV) is a vision-threatening complication in the eyes with pathological myopia, which is particularly prevalent among young and middle-aged Asians globally. To date, the verteporfin in photodynamic therapy study is the only randomized-controlled study in treatment of subfoveal myopic CNV. However, its long-term benefit is controversial. Recently, intravitreal injections of anti-vascular endothelial growth factors have shown promising results. In the absence of randomized-controlled trial comparing the efficacy of anti-vascular endothelial growth factors with photodynamic therapy and placebo, the purpose of this article is to review the current studies on functional and anatomical outcomes in both subfoveal and juxtafoveal myopic CNV. Furthermore, the influences of various doses and frequencies, as well as age and previous photodynamic therapy treatment on its effect are described.

Intravitreal bevacizumab versus photodynamic therapy for myopic choroidal neovascularization in a North-African population

PURPOSE

To compare the 1-year functional and anatomical outcomes of intravitreal bevacizumab (IVB) and photodynamic therapy (PDT) in patients with myopic choroidal neovascularization (CNV).

METHODS

Review of retrospectively collected data of 80 eyes in 80 patients with myopic CNV treated with standard PDT (n = 40) or IVB (1.25 mg/ 0.05 ml) (n = 40). Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) measured with optical coherence tomography (OCT) were compared between the two groups at baseline, 3, 6 and 12 months.

RESULTS

In the IVB group, mean BCVA was +0.9 ± 0.85 logMAR at baseline. Mean BCVA was significantly better at 3 and 6 months than baseline (p = .0095 and p = .008, respectively) but not at 12 months (p = .065). In the PDT group, mean BCVA was +0.88 ± 0.45 logMAR at baseline, and improved to +0.85 ± 0.62 logMAR at 3 months and to +0.86 ± 0.44 logMAR at 6 months, which was not significantly different from baseline. Mean BCVA then decreased to +0.9 ± 0.54 logMAR at 12 months (p = .85). Mean logMAR VA was significantly better in the IVB group than in the PDT group after 3 months (p = .0043), 6 months (p = .0001) and 12 months (p = .0168). Mean CRT was significantly lower in IVB group than in PDT group at 3, 6 and 12 months (p = .008, p = .038, p = .040, respectively). Chorioretinal atrophy developed in six eyes (15%) treated with IVB and in 24 eyes (60%) treated with PDT at 12 months (p = 3.2 × 10(-5)).

CONCLUSIONS

Over a 12-month period, intravitreal bevacizumab seems to be superior to photodynamic therapy in controlling myopic CNV in a North-African population.

Photodynamic therapy with verteporfin for choroidal neovascularization of pathologic myopia in Japanese patients: comparison with nontreated controls

PURPOSE

To examine the effects of photodynamic therapy (PDT) with verteporfin on subfoveal or juxtafoveal choroidal neovascularization (CNV) secondary to pathologic myopia in Japanese patients and to compare the visual outcomes of PDT-treated patients with that of age-matched and visual acuity-matched untreated controls.

DESIGN

Prospective, open-label, consecutive, interventional case series.

METHODS

We prospectively followed up 43 eyes of 42 consecutive patients with pathologic myopia (>6 diopters or axial length>26.5 mm) who received PDT for myopic CNV. In addition, the visual outcomes of these patients who were followed up for more than one year were compared with those of age- and initial visual acuity-matched untreated controls.

RESULTS

The average follow-up was 15.0+/-7.0 months. Patients received an average of 1.40+/-0.73 treatments during follow-up, and 30 eyes (69.8%) required only one treatment. The best-corrected visual acuity (BCVA) improved by more than two Snellen lines in seven eyes (16.3%), decreased in six eyes (14.0%), and remained stable in 30 eyes (69.7%). In three eyes with a juxtafoveal CNV, CNV could not be detected ophthalmoscopically or angiographically after PDT. Statistical analysis showed that the PDT-treated patients had significantly better visual acuity at one year after PDT than the age- and initial BCVA-matched untreated controls.

CONCLUSIONS

These results indicate that PDT was beneficial for maintaining vision in Japanese patients with myopic CNV. The visual outcome after PDT was better than the natural course of the disease as determined from untreated controls. The effect on chorioretinal atrophy around CNV should be investigated with a long-term study.

Intravitreal Bevacizumab (Avastin) for Myopic Choroidal Neovascularization

PURPOSE

To evaluate the safety and efficacy of intravitreal bevacizumab in the treatment of choroidal neovascularization (CNV) secondary to pathologic myopia (PM).

DESIGN

Prospective, consecutive, nonrandomized, interventional case series.

PARTICIPANTS

Twenty-two eyes of 22 patients with CNV secondary to PM.

METHODS

Consecutive patients with subfoveal or juxtafoveal CNV secondary to PM were recruited prospectively to receive an initial course of 3 monthly intravitreal injections of bevacizumab. Three additional monthly injections were performed in eyes with persistent CNV leakage after 3 months. Patients were followed up for 6 months, and the best-corrected visual acuity (BCVA), changes in fluorescein angiography, and optical coherence tomography (OCT) results were assessed.

MAIN OUTCOME MEASURES

Changes in BCVA, angiographic closure, and OCT central foveal thickness (CFT) at the 6-month follow-up.

RESULTS

The mean+/-standard deviation (SD) spherical equivalent refractive error of the 22 eyes was -10.3+/-3.7 D (range, -6.0D to -18.0D). All patients completed follow-up at 6 months. Twenty (90.9%) eyes had angiographic closure after 3 monthly injections of intravitreal bevacizumab, and 2 (9.1%) eyes required further treatment up to 6 months. The mean+/-SD logarithm of the minimum angle of resolution (logMAR) BCVA at baseline was 0.60+/-0.18 (Snellen equivalent, 20/80). At 1 and 6 months, the mean+/-SD logMAR BCVA improved significantly to 0.43 (Snellen equivalent, 20/53; P = 0.003) and 0.35 (Snellen equivalent, 20/45; P<0.001), respectively. The mean lines of improvements at 1 and 6 month compared with baseline were 1.7 and 2.6 lines, respectively. Fifteen (68.2%) eyes had an improvement of 2 or more lines at 6 months. The OCT results also showed significant reduction in CFT after treatment. No ocular or systemic complications were noted after intravitreal injections.

CONCLUSIONS

The 6-month outcomes suggest intravitreal bevacizumab to be a promising treatment method for CNV secondary to PM, resulting in both visual and anatomic improvements. Treatment resulted in complete absence of angiographic leakage in 90.9% of eyes at 3 months. Further studies to evaluate the safety, efficacy, and optimal treatment regimen are justified.