Current and emerging treatment options for myopic choroidal neovascularization

Progression of macular retinoschisis following intravitreal aflibercept injection for myopic macular neovascularization-a case report and review of literature

BACKGROUND

Macular retinoschisis (MRS) and myopic macular neovascularization (mMNV) are both potentially blinding complications of high myopia. In this case report, we highlight the progression of MRS after intravitreal anti-vascular endothelial growth factor (anti-VEGF) treatment for mMNV, as well as an extensive review of the literature on this topic.

CASE DESCRIPTION

A 49-year-old woman presented with two weeks of recent onset blurring and metamorphopsia in her right eye. She had high myopia in both eyes (right eye - 20/60 with - 16D, left eye - 20/20 with - 13D). Slit-lamp ophthalmoscopy found a normal anterior segment in both eyes. On fundus examination, features of pathological myopia with posterior staphyloma and peripapillary atrophy were observed in both eyes. An active mMNV, as well as intraretinal fluid, minimal perifoveal inner and outer MRS, and focal posterior vitreous traction along the inferotemporal retinal arcade, were detected on optical coherence tomography (OCT) of the right eye. The patient received an intravitreal injection of Aflibercept (2 mg/0.05 ml).

RESULTS

OCT scans at two- and four-month follow-up visits revealed regressed mMNV with a taut epiretinal membrane, progressive worsening of outer MRS, and the development of multiple perifoveal retinal detachment inferior to the fovea. Pars plana vitrectomy surgery was performed for the progressive MRS with good anatomical (resolved MRS) and functional outcome (maintained visual acuity at 20/60) at the last one-month post-surgery visit.

CONCLUSION

Intravitreal anti-VEGF injections for mMNV can cause vitreoretinal interface changes, exacerbating MRS and causing visual deterioration. Vitrectomy for MRS could be one of several treatment options.

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.

Different approaches for treating myopic choroidal neovascularization: a network Meta-analysis

AIM

To evaluate the efficacy of intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF), photodynamic therapy (PDT), and laser treatment (LT) for anatomical and functional improvement in myopic choroidal neovascularization (mCNV) patients.

METHODS

Two researchers independently searched PubMed, Cochrane Library, Web of Science, and other databases to screen studies comparing best-corrected vision acuity (BCVA) and foveal center thickness (FCT) changes after mCNV treatment. Post-treatment chorioretinal atrophy (CRA) is a secondary outcome indicator. The retrieval time limit is from the database construction to January 30, 2023.

RESULTS

A total of 1072 eyes in 16 articles were included. In the RCTs, intravitreal bevacizumab (IVB) and intravitreal ranibizumab (IVR) were superior to PDT (MD=0.18, 95%CI: 0.02, 0.40, MD=0.18, 95%CI: 0.01, 0.42) in improving BCVA of mCNV patients (P<0.05). The relative effectiveness in improving BCVA, from high to low, appeared to be IVR, intravitreal aflibercept (IVA), IVB, LT, PDT, and sham first followed by IVA (Sham/IVA). While improving the FCT from high to low was IVA, IVR, IVB, PDT. In retrospective studies, the results of BCVA after long-term treatment showed that all the therapeutic effects from high to low was IVA, intravitreal conbercept (IVC), IVR, IVB, IVB/IVR, PDT with IVB/IVR, PDT. The effect of improving FCT was IVA, IVR, IVC, PDT, and IVB from high to low. And in the effects of improving CRA, the IVB appeared to be higher than IVR, while the PDT was the smallest, but none of the differences in the results were statistically significant.

CONCLUSION

Anti-VEGF has the best effect on long-term vision improvement in mCNV patients, using IVB or IVR alone to treat mCNV may be better than IVB or IVR combined with PDT. There is no significant difference in the improvement of visual acuity, macular edema, and CRA in mCNV patients treated with any different anti-VEGF drugs.

Recurrence risk of myopic choroidal neovascularisation: a systematic review of current study

INTRODUCTION

The rising prevalence of myopia is a concern in ophthalmology, with myopic choroidal neovascularisation (m-CNV) significantly affecting vision. However, long-term outcomes of m-CNV management have been unsatisfactory, leading to high recurrence rates. These studies aim to identify risk factors for m-CNV recurrence.

METHODS

Comprehensive review followed a pre-registered plan in the International Prospective Register of Systematic Reviews (PROSPERO). The search strategy used various databases including PubMed, Cochrane Library, Embase, Scopus and ScienceDirect using the keywords 'Myopic Choroidal Neovascularization', 'Recurrence' and 'Risk'. Eligible studies were identified and analysed based on predetermined criteria. This study was registered on PROSPERO (CRD4202343461).

RESULTS

The systematic review included three retrospective studies investigating risk factors associated with m-CNV recurrence. These factors are: (1) requiring three or more injections for initial disease control, (2) older age, (3) larger myopic macular neovascularisation, (4) juxtafoveal CNV, (5) larger height of hyper-reflective foci (HRF) and (6) destruction or absence of the ellipsoid zone (EZ) and retinal pigment epithelium (RPE).

CONCLUSION

Risk factors for m-CNV recurrence include a greater number of required injections, older age, large macular CNV, juxtafoveal location, increased HRF height and changes in EZ and RPE structure. Understanding these factors can inform personalised treatment approaches and improve patient outcomes by identifying individuals at higher risk of recurrence and implementing proactive measures to mitigate the impact of m-CNV recurrence and progression. Further investigation is needed to enhance our understanding of the underlying mechanisms and develop innovative therapeutic approaches for effective m-CNV management.

PROSPERO REGISTRATION NUMBER

CRD4202343461.

Vitreoretinal Interface Changes After Anti-vascular Endothelial Growth Factor Treatment in Highly Myopic Eyes: A Real-World Study

INTRODUCTION

To investigate changes in the vitreoretinal interface after anti-vascular endothelial growth factor (anti-VEGF) treatment in highly myopic eyes.

METHODS

Eyes with myopic choroidal neovascularization (mCNV) treated with intravitreal injection of anti-VEGF in a single-center were retrospectively reviewed. Fundus abnormalities and features of optical computed tomography were studied.

RESULTS

A total of 295 eyes from 254 patients were recruited to the study. Prevalence of myopic macular retinoschisis (MRS) was 25.4%, and the rates of progression and onset of MRS were 75.9% and 16.2%, respectively. Outer retinal schisis (β = 8.586, p = 0.003) and lamellar macular hole (LMH) (β = 5.015, p = 0.043) at baseline were identified risk factors for progression and onset of MRS, whereas male sex (β = 9.000, p = 0.039) and outer retinal schisis at baseline (β = 5.250, p = 0.010) were risk factors for MRS progression. Progression of MRS was first detected in outer retinal layers in 48.3% of eyes. Thirteen eyes required surgical intervention. Spontaneous improvements of MRS were observed in five eyes (6.3%).

CONCLUSION

Changes in the vitreoretinal interface, such as progression, onset, and improvement of MRS, were observed after anti-VEGF treatment. Outer retinal schisis and LMH were risk factors of progression and onset of MRS after anti-VEGF treatment. Intravitreal injection of ranibizumab and retinal hemorrhage were protective factors for surgical intervention for vision-threatening MRS.

Incidence, predictors and re-treatment outcomes of recurrent myopic choroidal neo-vascularization

Objectives

To evaluate incidence, predictors, and re-treatment outcome of recurrent myopic choroidal neovascularization (m-CNV).

Methods

Retrospective consecutive observational series. From year 2014 to 2019, 167 eyes of 167 patients of treatment naïve m-CNV were enrolled. 59 and 108 eyes were treated with intra-vitreal ranibizumab and bevacizumab mono-therapy, respectively. Recurrence was defined as re-appearance of CNV activity, confirmed on optical coherence tomography (OCT) after at least 3 months of cessation of anti-VEGF therapy. Incidence of recurrence, predictors and re-treatment outcomes were studied.

Results

Overall, mean age and spherical equivalence (SE) was 47.95 ± 14.72 years and -12.19 ± 4.93 D respectively. Males constituted 50.9%. 44 eyes (26.4%) had a recurrence during a mean follow up of 16.5 ± 12.86 months. Kaplan-Meier survival analysis showed the risk of recurrence was 8, 26 and, 33.6% at 6, 12 and 18 months, respectively. Age (p = 0.511), gender (p = 0.218), SE (p = 0.092), anti-VEGF (p = 0.629) and baseline BCVA (p = 0.519) did not influence recurrence. Number of injections administered to control the disease in the first episode was the only significant predictor of recurrence (Cox Proportional Hazard Ratio 2.89–3.07, 95% Confidence Interval: 1.28–7.45; p = 0.005). At 12 months, eyes requiring one injection in first episode had a recurrence rate of 12% versus 45% in eyes requiring 3 or more injections in the first episode. A mean number of 1.9 additional injections per eye was needed during re-treatment. Final BCVA in the recurrence group was similar to that of non-recurrence group (0.53 ± 0.40 versus 0.55 ± 0.36 LogMAR; p = 0.755). Baseline BCVA (p = 0.0001) was the only predictor of final visual outcome irrespective of anti-VEGF drug (p = 0.38).

Conclusion

Eyes requiring greater number of injections for disease control in first episode are “at risk” of early m-CNV recurrence. However, recurrence does not adversely affect visual outcome, if treated adequately.

Baseline predictors for good visual gains after anti-vascular endothelial growth factor therapy for myopic choroidal neovascularization

To investigate optical coherence tomography (OCT) and OCT angiography (OCTA) biomarkers for good visual outcomes in eyes with myopic choroidal neovascularization (mCNV) following anti-vascular endothelial growth factor (anti-VEGF) therapy. Patients diagnosed with mCNV via multimodal imaging were retrospectively reviewed. Baseline demographic data and biomarkers were collected. Anti-VEGF treatment based on a pro re nata (PRN) regimen was conducted on all eyes. The visual gains of ≥ 15 ETDRS letters or < 15 letters at 12-month were classified into two groups. Regression analysis was used to identify variables associated with significant best-corrected visual acuity (BCVA) improvement. Among 34 patients, 17 eyes and 17 eyes were classified into the two groups. There were no statistically significant differences in qualitative OCTA biomarkers between the two groups. The ≥ 15 letters group had significantly thicker subfoveal choroid thickness (SFCT) (79.97 ± 33.15 vs. 50.66 ± 18.31, P = 0.003), more ellipsoid zone integrity (58.8% vs. 23.5%, P = 0.037) and lower levels of fractal dimension (1.45 ± 0.101 vs. 1.53 ± 0.082, P = 0.031) than the < 15 letters group. SFCT and the ellipsoid zone integrity were correlated with 15 letters or more VA improvement in both univariable and multivariable analyses (P = 0.023 and P = 0.044, respectively). Thicker SFCT and integrity of the ellipsoid zone at baseline were associated with greater visual gains at 12 months. OCTA biomarkers seem to play a less important role in predicting the visual outcome of mCNV.

TLR9 agonist suppresses choroidal neovascularization by restricting endothelial cell motility via ERK/c-Jun pathway

INTRODUCTION

Choroidal neovascularization (CNV) is the feature of neovascular age-related macular degeneration (AMD). It has been demonstrated that inflammation plays a key role in the development of CNV. Here we aim to investigate how TLR9 agonist (CpG-ODN), one of the key regulators of inflammatory responses, suppresses CNV in vivo.

MATERIALS AND METHODS

The cell viability was assessed by MTT and EdU test after CpG-ODN treatment. Endothelial cells gap assay, tube formation assay and transwell assay were practiced to observe how CpG-ODN affected the endothelial cells functions. The choroidal explants and laser-induced CNV model were built to investigate how CpG-ODN suppressed angiogenesis. The ERK and c-Jun expression were evaluated to assess if CpG-ODN affected cell proliferation. Flow cytometry and qPCR was practiced to observe how CpG-ODN regulated cell proliferation.

RESULTS

Our data showed that CpG-ODN not only reduced CNV area in vivo, but also decreased the RPE damage. CpG-ODN inhibited endothelial cells from migration and forming tubes, while the effect was not toxic. EdU test and MTT test suggested that CpG-ODN inhibited endothelial cells proliferation. CpG-ODN significantly increased protein expression of phosphorylated c-Jun but reduced phosphorylated ERK in HUVECs, which was confirmed in ERK transfected 293T cells. JNK inhibitor abolished the suppression of endothelial cells migration and tube formation by CpG-ODN. The findings were also in agreement with the observation in CpG-ODN treated CNV eyes in vivo. The flow cytometry and qPCR data revealed that the suppression of cell motility by CpG-ODN was achieved by arresting endothelial cells cell cycle at G0/G1 phase.

CONCLUSIONS

Our study demonstrated that CpG-ODN suppressed endothelial cell motility by restricting the cell cycle progression at G0/G1 phase, the effect of which was achieved by interacting with ERK/c-Jun pathways.

Three-year real-world outcomes of intravitreal anti-VEGF therapies in patients affected by myopic choroidal neovascularization

Purpose:

To describe real world data in patients affected by myopic choroidal neovascularization (CNV) treated with anti-vascular endothelial growth factors (VEGFs) and to compare our results with previous studies and clinical trials.

Methods:

This retrospective monocentric cohort study analyzed 96 eyes of 96 myopic-CNV patients treated with an anti-VEGF pro-re-nata regimen over a 3-year-long follow up period. Aflibercept and Ranibizumab were considered as first-line agents whereas Bevacizumab was reserved on a compassionate basis in patients outside the criteria for treatment. All patients underwent a best-corrected visual acuity (BCVA) recording at each follow up visit.

Results:

Our data showed that all three molecules produced significant improvements in BCVA at year 1, with no significant differences between the three drugs. Moreover, during the second year of treatment, Ranibizumab and Bevacizumab showed a significant improvement in the visual function. However, at year 3 of treatment, the data available indicated the BCVA improvement was not significant with Ranibizumab and Bevacizumab. In addition, no significant difference in the average number of injections between the three groups was detected over the follow up period. No serious adverse events were recorded, but five minor adverse events documented.

Conclusion:

Our study correlates with previous studies showing significant BCVA gains with the use of these molecules. Similarly, all three molecules seem to provide a similar duration of effects as previous studies have shown, with a low ocular adverse event rate.

Rural-urban differences in myopia prevalence among myopes presenting to Bhutanese retinal clinical services: a 3-year national study

PURPOSE

To determine the prevalence and demographic characteristics of myopia among patients presenting to the national vitreo-retinal (VR) services in Bhutan.

METHODS

The records of the VR clinic at the apex national referral centre, providing the only VR services in the country, were reviewed to identify all new myopia patients over three years. Thus, we surveyed all referrals nationally. The patients were categorised into urban and rural females and males. We assessed myopia prevalence in each group by occupational and educational categories. We examined univariate prevalence data and a multivariate logistic regression (MLR) identified independent factors.

RESULTS

Of 2913 cases 1544 (53.0%) were males. Females presented earlier (mean ±SD): overall 45.7 ± 21.9 cf. 48.6 ± 21.6 years, p = 0.003, and among myopes 23.9 ± 13.5 cf. 27.6 ± 18.6 years, p = 0.032. Myopia constituted 92.1% of refractive error, an overall prevalence of 12.3%. Myopia was more common among females (p = 0.01) and urbanites (p = 0.02). Myopia prevalence was highest among urban females (20.9%), followed by urban males (11.9%), rural females (6.8%), and rural males (5.2%). Logistic regression revealed that the odds of having myopia were increased by being a student (4.96 ×) or professional (1.96 ×), and decreased by rural living (1.75 ×), all p ≤ 0.038.

CONCLUSIONS

This is the first study on myopia in Bhutan. As observed throughout East and Southeast Asia, the prevalence of myopia was higher in females and urbanites and positively associated with formal education. Given known risk factors, these prevalences may be driven by educational pressures and reduced time spent outdoors.

Long-term outcomes of the intravitreal injection of ranibizumab for the treatment of choroidal neovascularization secondary to pathologic myopia

PURPOSE

To analyze the long-term outcomes and safety of intravitreal ranibizumab injections in myopic choroidal neovascularization (CNV).

METHODS

A retrospective non-randomized analysis of consecutive cases included 17 eyes from 17 patients with subfoveal myopic CNV, treated with intravitreal ranibizumab with at least 30-month follow-up. The patients received three injections monthly, followed by pro re nata regimen. Best-corrected visual acuity (BCVA) measurement, optical coherence tomography and fluorescein angiography were carried out at the baseline and at monthly intervals thereafter.

RESULTS

Mean follow-up period was 51 months (range 30-98 months). In 12 patients (70.6%), BCVA improved by at least 1 Snellen line, with at least 3-line improvement observed in the case of 8 eyes (47%). Mean central foveal thickness (CFT) decreased from 384.65 ± 103.3 µm at the baseline to 264 ± 86.2 µm at the last follow-up examination (p < 0.001). The final OCT examination revealed 59% (10/17) eyes with CNV-related macular atrophy. Mean number of injections over the follow-up period was 4.82 ± 2.04 per person. Nine patients (53%) required re-injection of the anti-VEGF agent; the mean number of re-injections in this group was 3.44 ± 1.34 per person (range 2-6). No significant adverse events were recorded during the study period.

CONCLUSIONS

Intravitreal ranibizumab is an effective and safe treatment for CNV secondary to pathologic myopia, contributing to long-term vision improvement and CFT reduction.

LONG-TERM OUTCOMES OF RANIBIZUMAB TREATMENT OF MYOPIC CHOROIDAL NEOVASCULARIZATION IN EAST-ASIAN PATIENTS FROM THE RADIANCE STUDY

A retrospective cohort study of East-Asian patients previously treated with ranibizumab for myopic choroidal neovascularization in the RADIANCE trial. Clinical charts were reviewed to assess long-term efficacy and safety. Visual acuity was sustained for additional 36 months after trial completion with few patients requiring additional treatment and no new safety concerns observed.

Purpose:

To evaluate long-term efficacy and safety of ranibizumab for treatment of myopic choroidal neovascularization (mCNV) in clinical practice.

Methods:

Noninterventional, retrospective cohort study of East-Asian patients previously treated with ranibizumab during the RADIANCE trial. Forty-one patients who completed the RADIANCE trial were followed-up for up to 48 months (post-RADIANCE observation period). Outcome measures were best-corrected visual acuity changes from baseline (assessed at RADIANCE trial initiation), mCNV recurrences, and ocular adverse events.

Results:

Mean visual gain from baseline best-corrected visual acuity (56.5 ± 12.1 letters) (20/80) was significant at 12 months (+14.3 ± 11.4 letters, n = 40, P < 0.0001), 24 months (+10.4 ± 22.3 letters, n = 31, P = 0.0143), 30 months (+11.0 ± 22.4 letters, n = 29, P = 0.0134), 42 months (+12.9 ± 20.9 letters, n = 25, P = 0.0051), and 48 months (+16.3 ± 18.7, n = 16, P = 0.0034). Of the 16 patients who completed 48 months of follow-up, 63% gained ≥10 letters and 13% lost ≥10 letters. Over the post-RADIANCE observation period, 83% of patients required no further treatment for mCNV, 10% experienced mCNV recurrences, and 12% experienced a nonserious ocular adverse event. Patients who required additional treatment for mCNV received a mean of 5.0 (SD 5.9, range 1.0–18.0) ranibizumab injections.

Conclusion:

Best-corrected visual acuity gained at the end of the RADIANCE trial was sustained over additional 36 months of follow-up. Few patients required further treatment and no new safety concerns were observed.

Pharmacotherapy of Myopic Choroidal Neovascularization

BACKGROUND

Myopic choroidal neovascularization (CNV) is a common cause of central visual loss in patients with high myopia, and the most common form of CNV in younger individuals. Pharmacologic therapy is the current mainstay of treatment of these patients.

METHODS

Review of pharmacological treatment options for myopic CNV, which primarily involves intravitreal administration of anti-vascular endothelial growth factor (anti-VEGF) agents.

RESULTS

At this time, anti-VEGF therapy agents are the first-line therapy in these patients. Comparative trials have not identified any major differences in treatment outcomes between aflibercept, bevacizumab, and ranibizumab. Only ranibizumab is approved for this indication in the US. Best visual outcomes are associated with younger age, smaller lesion size, and absence of chorioretinal atrophy.

CONCLUSION

Anti-VEGF therapy is generally very effective in the treatment of myopic CNV.

Clinical Efficacy and Safety of Current Interventions for Choroidal Neovascularization Associated with Rare Diseases: A Systematic Literature Review

INTRODUCTION

The aim of this systematic literature review was to evaluate the efficacy and safety of interventions for the treatment of choroidal neovascularization (CNV) secondary to etiologies other than age-related macular degeneration and pathologic myopia.

METHODS

Relevant randomized controlled trials (RCTs) and prospective observational studies were identified by searching MEDLINE, MEDLINE In-Process, EMBASE, and CENTRAL.

RESULTS

The search identified 5 RCTs; no relevant observational studies were identified. The studies differed in terms of underlying cause of CNV, patient numbers (n = 9-178), follow-up time (2-36 months) and quality assessment. In the largest RCT (n = 178 across a range of rare CNV etiologies), intravitreal ranibizumab showed superior efficacy versus sham from baseline to month 2 [mean best-corrected visual acuity (BCVA): + 9.5 vs. - 0.4 letters; p < 0.001]; the gain was maintained up to month 12. In the treatment of CNV secondary to presumed ocular histoplasmosis syndrome (POHS), both intravitreal ranibizumab and photodynamic therapy (PDT) showed significant improvement from baseline BCVA over the 12-month period (n = 9); however, all patients in the PDT group required rescue ranibizumab therapy. Unlicensed intravitreal bevacizumab was associated with a statistically significant improvement in BCVA compared to PDT at 12 months (p < 0.001) in patients with CNV secondary to multifocal choroiditis (n = 27). The use of steroids before PDT showed better BCVA outcomes than PDT alone (p < 0.05) in patients with idiopathic CNV (n = 20). Argon green laser therapy showed limited efficacy in patients with CNV secondary to OHS (n = 134).

CONCLUSION

There is evidence from a relatively large, good-quality study to support the use of intravitreal ranibizumab for the treatment of CNV secondary to rare diseases. However, the limited number of RCTs for this indication and differences in study characteristics between RCTs mean that there is uncertainty regarding comparative clinical effectiveness of interventions. RCTs with an active comparator are required to fully establish the comparative effectiveness of treatments for CNV secondary to rare diseases.

FUNDING

Novartis Pharmaceuticals UK Ltd, Surrey, UK.

Polypoidal Choroidal Vasculopathy in Highly Myopic Eyes with Elongated Axial Length

Purpose:

To retrospectively review the prevalence of myopia and elongated axial length in eyes with polypoidal choroidal vasculopathy (PCV) and to evaluate treatment response of PCV in highly myopic eyes. PCV has rarely been reported in myopic eyes.

Methods:

A retrospective review of all eyes diagnosed with PCV at the clinics of Retina Consultants of Hawaii and the Hawaii Macula and Retina Institute was performed between February of 2007 and April of 2017 to evaluate for eyes with significant myopia and elongated axial length.

Results:

A total of 282 eyes were diagnosed with PCV by ICG angiography. There were 144 males (59%) and 99 females (41%). 204 patients had unilateral PCV and 39 patients had bilateral PCV. A total of 3 patients with PCV had significant myopia less than -6 diopters or confirmed elongated axial length. One of these patients had bilateral PCV so there were 4 eyes noted with significant myopia and elongated axial length out of 282 eyes with PCV (1.4%). All 3 patients were Asian and presented with active leakage or bleeding related to PCV diagnosed on indocyanine green angiography and optical coherence tomography. Treatments typically used to treat PCV including intravitreal antiangiogenic medications and photodynamic therapy were utilized.

Conclusion and Importance:

High myopia is rare in eyes diagnosed with PCV, even though choroidal neovascularization is a common cause of vision loss in myopic macular degeneration. However, even in highly myopic eyes, PCV may show signs of resistance to antiangiogenic medications.

Diagnosis and treatment guideline for myopic choroidal neovascularization due to pathologic myopia

Pathologic myopia is a leading cause of visual impairment. Development of myopic choroidal neovascularization (CNV) is one of the most common complications that leads to central vision loss in patients with pathologic myopia. If left untreated, it can cause scarring with expanding macular atrophy leading to irreversible visual loss in a period as short as 5 years. Advancements in multimodal imaging technology have furthered our understanding of the condition; however, further studies are necessary to extend its utility in the diagnosis of myopic CNV. Intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy has become the standard-of-care and the recommended first-line treatment option for myopic CNV. Long-term studies have demonstrated that early treatment of confirmed myopic CNV cases with an intravitreal anti-VEGF agent is useful to avoid late-stage complications. This strategy has also been shown to achieve visual outcome improvements for up to 4 years and visual stabilization up to 6 years. This review article provides an overview of the current knowledge on myopic CNV and discusses recent updates in the diagnosis and management of the condition. Furthermore, treatment recommendations are provided based on the authors' expert opinions.

Magnetic nanoparticles: a strategy to target the choroidal layer in the posterior segment of the eye

Despite the higher rate of blindness due to population aging, minimally invasive and selective drug delivery to the eye still remains an open challenge, especially in the posterior segment. The retina, the retinal pigment epithelium (RPE) and the choroid are posterior segment cell layers, which may be affected by several diseases. In particular, damages to the choroid are associated with poor prognosis in the most severe pathologies. A drug delivery approach, able to target the choroid, is still missing. Recently, we demonstrated that intravitreally injected magnetic nanoparticles (MNP) are able to rapidly and persistently localise within the RPE in an autonomous manner. In this work we functionalised the MNP surface with the vascular endothelial growth factor, a bioactive molecule capable of transcytosis from the RPE towards more posterior layers. Such functionalisation successfully addressed the MNPs to the choroid, while MNP functionalised with a control polypeptide (poly-L-lysine) showed the same localisation pattern of the naked MNP particles. These data suggest that the combination of MNP with different bioactive molecules could represent a powerful strategy for cell-specific targeting of the eye posterior segment.

Mining for genes related to choroidal neovascularization based on the shortest path algorithm and protein interaction information

BACKGROUND

Choroidal neovascularization (CNV) is a serious eye disease that may cause visual loss, especially for older people. Many factors have been proven to induce this disease including age, gender, obesity, and so on. However, until now, we have had limited knowledge on CNV's pathogenic mechanism. Discovering the genes that underlie this disease and performing extensive studies on them can help us to understand how CNV occurs and design effective treatments.

METHODS

In this study, we designed a computational method to identify novel CNV-related genes in a large protein network constructed using the protein-protein interaction information in STRING. The candidate genes were first extracted from the shortest paths connecting any two known CNV-related genes and then filtered by a permutation test and using knowledge of their linkages to known CNV-related genes.

RESULTS

A list of putative CNV-related candidate genes was accessed by our method. These genes are deemed to have strong relationships with CNV.

CONCLUSIONS

Extensive analyses of several of the putative genes such as ANK1, ITGA4, CD44 and others indicate that they are related to specific biological processes involved in CNV, implying they may be novel CNV-related genes.

GENERAL SIGNIFICANCE

The newfound putative CNV-related genes may provide new insights into CNV and help design more effective treatments. This article is part of a Special Issue entitled "System Genetics" Guest Editor: Dr. Yudong Cai and Dr. Tao Huang.