Aqueous Concentrations of Vascular Endothelial Growth Factor in Eyes with High Myopia with and without Choroidal Neovascularization

Myopic choroidal neovascularization with neovascular signal around perforating scleral vessel prone to recur after anti-VEGF therapy

BACKGROUND

To compare the recurrence of myopic choroidal neovascularization (mCNV) based on the neovascular signal of mCNV around the perforating scleral vessel (PSV).

METHODS

A consecutive series of naïve patients with mCNV accepted anti-VEGF therapy with a minimum 12-month follow-up period. The neovascular signal relationship between PSV and mCNV were classified into the presence of neovascular signal of CNV around PSV or not. The recurrence of mCNV, best-corrected visual acuity (BCVA), hyperreflective foci height, CNV area and CNV flow area were analyzed between two groups.

RESULTS

Neovascular signal of CNV around PSV was detected in 20 eyes (39.2%). The one-year recurrence rate in the group with neovascular signal of CNV around PSV was significantly higher than that in the group without neovascular signal of CNV around PSV (P = 0.045). The recurrence time in the group with neovascular signal around PSV was shorter than that in the group without neovascular signal around PSV (P = 0.030). Cox proportional hazard model showed that the presence of neovascular signal of CNV around PSV [hazard ratio (HR): 2.904] and subfoveal choroidal thickness ≤ 50 μm (HR: 0.368) were risk factors for recurrence of mCNV. In the group with neovascular signal around PSV, the BCVA was worse (P = 0.024) and the CNV flow area was more unstable (P = 0.027) after therapy.

CONCLUSIONS

PSV was commonly detected in patients with mCNV. The presence of neovascular signal of CNV around PSV was prone to recur with a shorter time in mCNV patients.

Identification of Potential Therapeutic Targets for Myopic Choroidal Neovascularization via Discovery-Driven Data Mining

Purpose: Myopic choroidal neovascularization (mCNV) is a prevalent cause of vision loss. However, the development of effective therapeutic targets for mCNV has been hindered by the paucity of suitable animal models. Therefore, the aim of this study is to identify potential genes and pathways associated with mCNV and to unearth prospective therapeutic targets that can be utilized to devise efficacious treatments.Methods: Text data mining was used to identify genes linked to choroid, neovascularization, and myopia. g: Profiler was utilized to analyze the biological processes of gene ontology and the Reactome pathways. Protein interaction network analysis was performed using strings and visualized in Cytoscape. MCODE and cytoHubba were used for further screening.Results: Discovery-driven text data mining identified 55 potential genes related to choroid, neovascularization, and myopia. Gene enrichment analysis revealed 11 biological processes and seven Reactome pathways. A protein-protein interaction network with 47 nodes was constructed and analyzed using centrality ranking. Key clusters were identified through algorithm tools. Finally, 14 genes (IL6, FGF2, MMP9, IL10, TNF, MMP2, HGF, MMP3, IGF1, CCL2, CTNNB1, BDNF, NGF, and EDN1), in addition to VEGFA, were evaluated as targets with potential as future therapeutics.Conclusions: This study provides new potential therapeutic targets for mCNV, including IL6, FGF2, MMP9, IL10, TNF, MMP2, HGF, MMP3, IGF1, CCL2, CTNNB1, BDNF, NGF, and EDN1, which correspond to seven potential enriched pathways. These findings provide a basis for further research and offer new possibilities for developing therapeutic interventions for this condition.

Pathogenesis of myopic choroidal neovascularization: A systematic review and meta-analysis

Myopic choroidal neovascularization (CNV) is a vision-threatening complication of high myopia. Here, we systematically review cohort, case-control, and cross-sectional studies in PubMed, Embase, and Web of Science, and summarize the associated factors of myopic CNV using meta-analysis where applicable. Among 1,333 records assessed, 50 were found eligible, all having a low-to-moderate risk of bias. Highly myopic eyes with CNV had a higher risk of lacquer cracks (odds ratio = 2.88) and patchy chorioretinal atrophy (odds ratio = 3.43) than those without. The mean posterior staphyloma height (µm) was greater in myopic CNV eyes than in highly myopic eyes without CNV (mean difference = 82.03). The thinning of choroidal thickness (µm) between myopic eyes with and without CNV differed significantly (mean difference = -47.76). The level of vascular endothelial growth factor (pg/ml) in the aqueous humor of myopic CNV eyes was significantly higher than in highly myopic eyes without CNV (mean difference = 24.98), the same as interleukin-8 (IL-8) (pg/ml, mean difference = 7.73). Single-nucleotide polymorphisms in the vascular endothelial growth factor, complement factor I, and collagen type VIII alpha 1 genes were associated with myopic CNV. We found that myopic CNV eyes have a higher ratio of lacquer cracks and patchy chorioretinal atrophy, thinner choroid, greater posterior staphyloma height, and a higher level of vascular endothelial growth factor and IL-8 in aqueous. Structural predisposing lesions, hemodynamic, genetic, and systemic factors are also associated with myopic CNV.

Evidence of vascular involvement in myopia: a review

The benign public perception of myopia (nearsightedness) as a visual inconvenience masks the severity of its sight-threatening consequences. Myopia is a significant risk factor for posterior pole conditions such as maculopathy, choroidal neovascularization and glaucoma, all of which have a vascular component. These associations strongly suggest that myopic eyes might experience vascular alterations prior to the development of complications. Myopic eyes are out of focus because they are larger in size, which in turn affects their overall structure and function, including those of the vascular beds. By reviewing the vascular changes that characterize myopia, this review aims to provide an understanding of the gross, cellular and molecular alterations identified at the structural and functional levels with the goal to provide an understanding of the latest evidence in the field of experimental and clinical myopia vascular research. From the evidence presented, we hypothesize that the interaction between excessive myopic eye growth and vascular alterations are tipping-points for the development of sight-threatening changes.

Difference in aqueous concentration and vitreous mass of cytokines in high myopias with and without choroidal neovascularization

PURPOSE

To investigate and compare the aqueous humor (AH) concentration and vitreous mass of cytokines in high myopias (HM) with and without myopic choroidal neovascularization (mCNV). And the correlations between cytokines and the size of CNVs on optical coherence tomography angiography (OCTA) images were also be analyzed.

METHODS

This observational study included 56 highly myopic eyes with and without CNV and 57 control eyes with cataracts. AH samples were obtained prior to the intravitreal injection of anti-VEGF and cataract surgery. This study measured multiple inflammatory cytokines including VEGF, interleukin (IL)-6, IL-8, IL-10, interferon-inducible protein-10 (IP-10), and monocyte chemotactic protein-1 (MCP-1) by multiplex bead assay. AH cytokine level, axial length, and vitreous volume were used to calculate the vitreous mass of cytokines.

RESULTS

The vitreous mass of VEGF in eyes with mCNV was significantly higher than that in control group. However, the difference in AH concentration of VEGF between high myopias with mCNV was not observed. Inflammatory cytokines were upregulated (IL-6, IL-10, and MCP-1) in highly myopic eyes both with and without mCNV (all P<0.05). There was also a significant difference in the vitreous mass of IL-8 and IP-10 among all three groups (P<0.05).

CONCLUSION

We confirmed the secretion of VEGF increased in eyes with mCNV from a new perspective. The development of both HM and mCNV were related to inflammatory cytokines and the upregulation of inflammatory cytokines may precede upregulation of VEGF. The vitreous mass might be tried as a more reliable potential biomarker in eyes with longer axial length.

Characteristics of choroidal neovascularization in elderly eyes with high myopia not meeting the pathologic myopia definition

The META-Analysis of Pathologic Myopia Study group proposed a new classification system for myopic maculopathy (MM) with pathologic myopia (PM) defined as MM equal to/more serious than diffuse atrophy or the presence of plus lesions and myopic choroidal neovascularization (mCNV) defined as CNV in the eye with PM. However, CNV in elderly eyes with high myopia (HM) not meeting the PM definition (high-myopia CNV) are not classified as age-related macular degeneration (nAMD) or mCNV. This retrospective study included 39 eyes with high-myopia CNV, 20 eyes with mCNV, and 20 eyes with AMD. All patients were at least 40 years old. We compared the clinical characteristics and treatment outcomes among three groups. The high-myopia CNV group had significantly more CNV types, shorter axial length and fewer lacquer cracks (P < 0.0001, respectively); larger baseline greatest linear dimension (P = 0.0002), more fellow-eye drusen (P = 0.0106), more men (P = 0.0029), and more treatments (24 months, P = 0.0098) compared to the mCNV group. Compared with the nAMD group, the high-myopia CNV group was significantly younger (P = 0.0041), and had fewer CNV types (P = 0.0316), more lacquer cracks (P = 0.0079) and fewer drusen (affected-eye, P = 0.0006 and fellow-eye, P = 0.0222), and fewer treatments (24 months, P = 0.0030). Because the CNV in elderly eyes with HM not meeting the PM definition is classified as combined mCNV and nAMD, the clinical and angiographic findings are critical to determine the treatment strategy.

Comparison of Intraocular Cytokine Levels of Choroidal Neovascularization Secondary to Different Retinopathies

Purpose: To investigate and compare the aqueous concentrations of vascular endothelial growth factor (VEGF) and other inflammatory cytokines in various choroidal neovascularization (CNV) diseases and types.

Methods: This observational study included 127 naive eyes with CNV and 43 control eyes with cataracts. Aqueous humor (AH) samples were obtained prior to intravitreal anti-VEGF injection or cataract surgery. Multiple inflammatory cytokines, including VEGF, interleukin (IL) 6, IL-8, IL-10, interferon-inducible protein 10 (IP-10), and monocyte chemotactic protein 1 (MCP-1) levels, were measured using a multiplex bead assay. The angiogenesis index was defined as the ratio of IP-10 to MCP-1. In addition, the relationship among AH cytokine levels, central macular thickness (CMT), and CNV size on optical coherence tomography angiography (OCTA) was evaluated.

Results: Except in the myopic CNV group (P = 0.452), the AH concentration of VEGF was significantly higher in all other CNV groups than in the control group (P < 0.05 for all comparisons). IL-8, IL-10, IP-10, and MCP-1 levels (P < 0.05 for all groups) were significantly higher in all CNV diseases except those with neovascular central serous chorioretinopathy. The angiogenesis index was significantly higher in all CNV diseases (P < 0.05 for all comparisons). The VEGF level may be associated with the size of the CNV on OCTA (p = 0.043).

Conclusions: The level of intraocular inflammatory cytokines varied among different CNV diseases and CNV types. Therefore, the angiogenesis index may be a more sensitive indicator of angiogenesis.

Biomarkers of Myopic Choroidal Neovascularization in Women, Determining the Clinical Course and Response to Anti-VEGF Therapy

Aim: to identify clinical and laboratory biomarkers that determine the nature of the course of myopic choroidal neovascularization (mCNV) and the response to anti-VEGF therapy in women.

Material and methods. A prospective non-randomized study was conducted in 52 patients (52 eyes) with active mCNV, treated with ranibizumab intravitreally, 0.5mg. After 12months, the suppression of CNV activity, the number of injections and the fellow eye inclusion in the pathological process were taken into account. There were 2 groups: with a favorable clinical course (n = 31, age – 33,0 ± 5,1 years, anterior-posterior axis (APA) 28,5 ± 0,3 mm) and an unfavorable clinical course (n = 21, age – 34,0 ± 4,1 years, APA – 29,01 ± 0,1 mm). Structural retinal changes, choroid thickness, retinal blood flow, and heart rate were evaluated using OCT and OCTA protocols (Optovue XR Avanti, USA). Studies were conducted before the start of therapy and then one time per month. The concentration of sex and pituitary hormones (ELISA analyzer “Immunohem-2100”), lipoprotein A, Apo B/Apo A (Accent 200 Cormay, Poland), coagulogram data (Helena C-2, UK), and the concentration of highly sensitive C-reactive protein in blood serum before the start of antiangiogenic therapy were studied once.

Results. In the first group, 1.4 ± 0.7 ranibizumab injections were administered to suppress the CNV activity. In the opposite group – 3.5 ± 2.1 injections, in 73.7 % of cases, relapses were diagnosed, in 3 cases – primary CNV in the fellow eye. Clinical and laboratory biomarkers of the unfavorable clinical course of mCNV were identified: extreme choroidal thinning, highly organized membranes of a large area, dome-shaped deformation of the posterior pole, excess of the reference values of lipoprotein A, fibrinogen and highly sensitive C-reactive protein by two or more times, an imbalance of sex and pituitary hormones (excess of the reference values of prolactin, follicle stimulating hormone, cortisol, progesterone concentration decrease), a predominant change in the menstrual-ovarian cycle according to the type of amenorrhea and opsomenorrhea.

Conclusion. Myopic CNV biomarkers in women allow predicting the response to anti-VEGF therapy, the formation of relapses and the inclusion of the fellow eye in the pathological process. 

Anti-VEGF Therapy in Myopic CNV

In this narrative-review, we report the most recent data from the literature of anti-vascular endothelial growth factor treatment for myopic choroidal neovascularization (mCNV). Myopic CNV is the most frequent sight-threatening complication of pathologic myopia. The natural course of mCNV can result in expanding macular atrophy and /or fibrosis, leading to irreversible visual loss after 5 years. Retinal multimodal imaging is mandatory for early diagnosis and monitoring of the disease during treatment. Intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy is recommended as the first-line treatment option for mCNV. Prompt treatment of active mCNV with intravitreal anti-VEGF therapy has been demonstrated to be effective in terms of visual outcome improvements reducing the occurrence of late-stage complications.

Flow pattern and perforating vessels in three different phases of myopic choroidal neovascularization seen by swept-source optical coherence tomography angiography

PURPOSE

To compare the choroidal neovascularization (CNV) flow patterns and the relationship between perforating vessels (PVs) and CNV in the three different stages of networks in myopic CNV (mCNV) using swept-source optical coherence tomography angiography (SS-OCTA).

METHODS

This retrospective study included 28 eyes with mCNV that was divided into three phases (active, scar, and atrophic) and observed by SS-OCTA. SS-OCTA findings, with special focus on the relationship between the PVs and CNV, were compared among the three phases.

RESULTS

Overall, the CNV signal was detected in 31 of the 34 areas of CNV (91%); in the active, scar, and atrophic phases, respectively, CNV signals were detected in eight of eight areas of CNV (100%), 10 of 11 areas of CNV (91%), and 13 of 15 areas of CNV (86%). Two signal patterns were observed in each phase, i.e., dense and loop; in the atrophic phase, seven eyes were unclassifiable. The ratio between the dense and loop patterns did not differ significantly among the phases. In 30 of 34 areas of CNV for which clear images were obtained, the PVs and CNV were connected directly or indirectly in 19 area of CNV, and in five areas of CNV, trunk-like vessels were connected to the PVs within the CNV. The numbers of foveal or parafoveal CNVs accompanied by PVs were significantly (p=0.0048) greater than those of the extrafoveal CNV.

CONCLUSIONS

OCTA provides detailed observation of mCNV and the relationship between CNV and PVs. Although the CNV signal pattern does not differ depending on the degree of atrophy, there are cases in which only the trunk-like vessels connect to the PVs within the CNV in the atrophic phase without CNV flow signal.

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.

Relationship Between Aqueous Humor Levels of Cytokines and Axial Length in Patients With Diabetic Retinopathy

PURPOSE

A negative relationship between intraocular vascular endothelial growth factor-A (VEGFA) and axial length was found, which may help explain why myopia with long axial length was a protective factor for development of diabetic retinopathy (DR). The aim of this study is to further assess the relationship between the aqueous humor levels of interlukin (IL)-8, IL-10, VEGFA, vascular adhesion molecule-1 (VCAM-1), basic fibroblast growth factor, VEGFB, and placental growth factor (PLGF) and axial length in eyes with DR.

DESIGN

Retrospective, single-center, unmasked study.

METHODS

Patients with age-related cataract and with/without DR who visited the Department of Ophthalmology at the Affiliated Hospital of Inner Mongolia Medical University were enrolled. The level of IL-8, IL-10, VEGFA, VCAM-1, and basic fibroblast growth factor were measured by cytometric bead array, and VEGFB and PLGF were measured by enzyme-linked immunosorbent assay. Axial length was measured by biometry.

RESULTS

Totally 65 eyes of 65 patients were enrolled, including 14 patients with nonproliferative diabetic retinopathy, 16 patients with proliferative diabetic retinopathy (PDR), and 35 patients with age-related cataract as control. In the nonproliferative diabetic retinopathy group, the aqueous level of PLGF was negatively correlated with axial length (r = -0.576, P = 0.031), whereas the aqueous levels of IL-10 (r = 0.533, P = 0.049) and VCAM-1 (r = 0.566, P = 0.035) were positively correlated with axial length. In the proliferative diabetic retinopathy group, all cytokines did not significantly correlate with axial length.

CONCLUSIONS

Among patients with diabetic retinopathy, we further found that aqueous levels of PLGF were negatively correlated with axial length, whereas VCAM-1 and IL-10 were positively correlated with axial length. These findings may suggest that these cytokines play a role in the development of DR, and further explain the relationship between the axial length and DR.

Correlation of axial length and myopic macular degeneration to levels of molecular factors in the aqueous

To elucidate the molecular processes associated with the development of myopic macular degeneration (MMD), we measured the intraocular concentrations of molecular factors in emmetropic and myopic eyes. This is a retrospective clinic-based case-control study that included eyes undergoing routine cataract surgery whereby aqueous humour samples were obtained. We measured the concentrations of pigment epithelium derived factor(PEDF), matrix metalloproteinase 2(MMP-2), tissue inhibitor of metalloproteinase(TIMP-2), vascular endothelial growth factor isoform A(VEGF-A), interleukin 8(IL-8), interleukin 6(IL-6), C-reactive protein(CRP), angiopoietin 2(Ang2), and amphiregulin. 38 eyes (axial length (AL): 22.4–32.4 mm), including 12 highly myopic (HM) eyes (AL ≥ 26.5 mm) without MMD and 12 HM eyes with MMD but without neovascularization were included. Eyes with MMD were found to have significantly lower VEGF-A levels (p = 0.007) and higher MMP-2 levels (p = 0.02) than control eyes after adjusting for age and gender. MMP-2 levels correlated positively (r = 0.58, p = 0.002), while VEGF-A levels correlated negatively with longer axial length (r = −0.75, p < 0.001). Both the concentrations of VEGF-A (P = 0.25) and MMP-2 (P = 0.69) were not significantly associated with MMD after adjusting for AL. These findings suggest that the predominant mechanism underlying the development of non-neovascular MMD may be axial elongation, driven in part by MMP-2 related mechanisms.

Real-world data on ranibizumab for myopic choroidal neovascularization due to pathologic myopia: results from a post-marketing surveillance in Japan

Objectives

The aim of this study was to obtain real-world clinical data on the safety and efficacy of ranibizumab treatment for myopic choroidal neovascularization (CNV) due to pathologic myopia.

Methods

This was a prospective, observational, post-marketing surveillance study in ranibizumab-naive Japanese patients with myopic CNV. Patients who initiated ranibizumab treatment were registered and prospectively observed over 12 months. Safety endpoints were the incidence of ocular and non-ocular adverse drug reactions (ADRs) and serious adverse events (SAEs). The efficacy endpoint included the average change in best-corrected visual acuity (BCVA) in logarithm of the minimal angle of resolution (logMAR) units (logMAR BCVA) from baseline to the last observation.

Results

Three hundred and eighteen patients were included in the safety analysis population. Of these 79.9% were female and the mean age was 65.5 years. The incidences of SAEs and ADRs were 0.6 and 0.3%, respectively. A total of 268 patients (84.0%) completed the 12-month study period. The mean (±SD) and median number of ranibizumab injections were 2.0 ± 1.5 and 1.0 during the 12-month study period, respectively. The number of ranibizumab injections received was one in 52.2% of patients and less than or equal to three in 89.2%. The mean change in logMAR BCVA from baseline to month 12 was −0.193, and the mean logMAR BCVA improved from 0.517 to 0.319 between baseline and month 12.

Conclusions

This study showed that ranibizumab is generally well tolerated, and that a minimum number of injections were necessary to produce a therapeutic effect in Japanese myopic CNV patients in a real-world setting.

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.

[Role of immunological factors in the development of myopic choroidal neovascularization]

AIM

To study the concentration of cytokines in the aqueous humor of the anterior chamber in patients with myopic choroidal neovascularization (mCNV) and to compare the results to their ophthalmic status.

MATERIAL AND METHODS

A total of 19 patients (19 eyes) with mCNV treated with intravitreal ranibizumab were included in the study. The control group consisted of 15 patients (15 eyes) with myopia who had cataract surgery. Age, sex, and refractive error distribution were similar to that in the study group. All patients underwent a detailed ophthalmic examination as well as immunological study of the aqueous humor for cytokines concentrations using flow fluorometry (Bio-Plex Pro Human Cytokine Panel, 27-Plex, Bio-Rad Laboratories, USA).

RESULTS

Significant differences in concentrations of 10 cytokines were found between the mCNV and study groups. Vascular endothelial growth factor (VEGF) level was twice as low in patients with mCNV as that in the controls (191.15±142.3 pg/ml and 320.06±170.05 pg/ml, respectively) (p<0.05). The other 9 cytokines were higher in mCNV, namely, platelet-derived growth factor (PDGF-BB), inflammatory and anti-inflammatory cytokines (IL-2, IL-15, IL-17А and IL-5, IL-13, respectively), tumor necrosis factor (TNFα), and chemokines (IL-8, RANTES). The degree of myopia as well as morphological and functional changes in the macular zone were shown to be in close correlation with cytokines involved in inflammation and VEGF. VEGF level appeared to be negatively related to axial eye length, refractive error, and three cytokines: IL-13, INF-γ, and RANTES. At the same time, numerous (6, 8 and more) close correlations were established between inflammatory and anti-inflammatory cytokines, chemokines, and growth factors.

CONCLUSION

Patients with mCNV have been found to have higher than usual levels of inflammatory and anti-inflammatory cytokines, chemokines, and growth factors as well as a significantly decreased VEGF concentration. Immunological status of these patients differs from that in other ocular neovascular diseases suggesting possible involvement of alternative pathogenetic mechanisms.

Complications of Pathologic Myopia

Pathologic myopia (PM) is one of the leading causes of visual impairment worldwide. The pathophysiology of PM is not fully understood, but the axial elongation of the eye followed by chorioretinal thinning is suggested as a key mechanism. Pathologic myopia may lead to many complications such as chorioretinal atrophy, foveoschisis, choroidal neovascularization, rhegmatogenous retinal detachment, cataract, and glaucoma. Some complications affect visual acuity significantly, showing poor visual prognosis. This article aims to review the types, pathophysiology, treatment, and visual outcome of the complications of PM.

[Modern views on myopic maculopathy]

Most of world's scientists consider the fast-growing incidence of myopia a problem of great social importance due to associated increase in complicated myopia that leads to disability among the working-age population. This is a review on complicated myopia and myopic maculopathy that covers the history of research in this field, principles of classification, and etiological factors. It also deals with choroidal neovascularization (CNV), which often follows, and its treatment options, including anti-VEGF therapy. Possible complications of the latter are described as well. Literature search was done using PubMed, eLIBRARY, and Scopus text databases. A total of 61 sources, both Russian and foreign, were analyzed. Current clinical knowledge of different types of myopic maculopathy is still insufficient and the gaps are likely to be filled using modern methods of detailed in vivo examination of both sclera and choroidea. Anti-VEGF therapy has proved most effective in treating myopic maculopathy-associated neovascularization, however, a systematic approach to patient selection and management is yet needed.

Intravitreal vascular endothelial growth factor concentration and axial length

BACKGROUND

To examine the intravitreal concentration of vascular endothelial growth factor (VEGF) in dependence of the axial length in eyes without intraocular neovascularization.

METHODS

The concentrations of VEGF in vitreous samples and blood samples of patients undergoing pars plana vitrectomy for treatment of idiopathic macular holes or epiretinal membranes were examined using enzyme-linked immunosorbent assay. Axial length was determined by biometry.

RESULTS

The study included 34 patients with macular holes (n = 21) or epiretinal membranes (n = 13) with a mean age of 62.4 ± 10.5 years (range: 35-76 years) and a mean axial length of 24.1 ± 1.8 mm (range: 21.0-29.1 mm). The intravitreal VEGF concentration (mean: 71.0 ± 63.2 pg/mL) was significantly (P < 0.001) lower than the VEGF concentration in the blood (830 ± 585 pg/mL). Both parameters were significantly associated with each other (P = 0.04; correlation coefficient r = 0.35). The intravitreal VEGF concentration was not significantly associated with gender (P = 0.25) or age (P = 0.48). A higher intravitreal VEGF concentration was significantly associated with a shorter axial length (P = 0.025; r = -0.39) or a higher hyperopic refractive error (P = 0.04; r = 0.35). Neither plasma concentration of VEGF nor the ratio of plasma VEGF concentrations to intravitreal VEGF concentration was significantly associated with axial length (P = 0.89 and P = 0.22, respectively) or with refractive error (P = 0.89 and P = 0.26, respectively).

CONCLUSION

Intravitreal VEGF concentration decreased with increasing axial length. It suggests a diluting effect in eyes with larger intraocular volume and/or a faster turnover rate of VEGF in axially myopic eyes with vitreous liquefaction.

Oxidative stress in myopia

Myopia affected approximately 1.6 billion people worldwide in 2000, and it is expected to increase to 2.5 billion by 2020. Although optical problems can be corrected by optics or surgical procedures, normal myopia and high myopia are still an unsolved medical problem. They frequently predispose people who have them to suffer from other eye pathologies: retinal detachment, glaucoma, macular hemorrhage, cataracts, and so on being one of the main causes of visual deterioration and blindness. Genetic and environmental factors have been associated with myopia. Nevertheless, lack of knowledge in the underlying physiopathological molecular mechanisms has not permitted an adequate diagnosis, prevention, or treatment to be found. Nowadays several pieces of evidence indicate that oxidative stress may help explain the altered regulatory pathways in myopia and the appearance of associated eye diseases. On the one hand, oxidative damage associated with hypoxia myopic can alter the neuromodulation that nitric oxide and dopamine have in eye growth. On the other hand, radical superoxide or peroxynitrite production damage retina, vitreous, lens, and so on contributing to the appearance of retinopathies, retinal detachment, cataracts and so on. The objective of this review is to suggest that oxidative stress is one of the key pieces that can help solve this complex eye problem.

Intracameral interleukin 1β, 6, 8, 10, 12p, tumor necrosis factor α and vascular endothelial growth factor and axial length in patients with cataract

Objective

To assess associations between the aqueous humour concentration of interleukin IL-1β, IL-6, IL-8, IL-10 and IL-12p, tumor necrosis factor α (TNF-α) and vascular endothelial growth factor (VEGF) and axial length in eyes with cataract.

Methods

The hospital-based investigation included patients who underwent cataract surgery between March 2014 and April 2014. Using aqueous humour collected at the start of cataract surgery, the interleukins IL-1β, IL-6, IL-8, IL-10 and IL-12p, TNF-α and VEGF were examined using a cytometric bead array. Axial length was determined by partial coherence laser interferometry (IOL Master).

Results

The study included 33 patients with cataract (33 eyes) with a mean age of 69.2±10.8 years (range:50–87 years) and a mean axial length of 24.7±1.9 mm (range:22.6–31.5 mm). Lower aqueous concentration of VEGF was significantly associated with longer axial length (VEGF concentration (pg/mL) = -5.12 x Axial Length (mm) + 163; correlation coefficient r = -0.41; P<0.001) and more myopic refractive error (VEGF concentration (pg/mL) = 1.27xspherical equivalent (diopters)+44.8; r = 0.383; P = 0.002). The aqueous concentrations of all other substances were not significantly (all P>0.10) associated with axial length or refractive error.

Conclusions

Higher intravitreal concentrations of VEGF were measured in eyes with a longer axial length, while the intraocular concentrations of IL-1β, IL-6, IL-8, IL-10, IL-12p and TNF-α were not correlated with axial length. The lower concentration of VEGF in axially elongated eyes may be one of the reasons for the lower prevalence of age-related macular degeneration and diabetic retinopathy in myopic eyes.

Correlation of macular choroidal thickness with concentrations of aqueous vascular endothelial growth factor in high myopia

PURPOSE

To investigate the association of both aqueous and serum vascular endothelial growth factor (VEGF) levels and macular choroidal thickness in high myopia.

MATERIALS AND METHODS

VEGF concentrations were measured in aqueous and serum samples via enzyme-linked immunosorbent assay (ELISA) and compared between high myopia (n = 36 eyes, 36 patients) and normal control (n = 42 eyes, 42 patients) eyes. Macular choroidal thickness, the distance from the retinal pigment epithelium (RPE) to the scleral interface, was determined via enhanced depth-imaging optical coherence tomography (EDI-OCT). Axial length was measured using the intraocular (IOL) lens Master.

RESULTS

Aqueous levels of VEGF from high myopia patients were significantly lower compared with those from control persons (61.4 ± 27.6 versus 122.6 ± 52.4 pg/ml; p < 0.001), respectively. Macular choroidal thickness of high myopia patients was significantly lower compared with that of control persons (111.1 ± 45.0 versus 230.6 ± 81.8 μm; p < 0.001), respectively. Aqueous levels of VEGF were significantly associated with both macular choroidal thickness (R(2)= 0.641; p < 0.001) and axial length (R(2)= 0.679; p < 0.001) in high myopia patients. In addition, there was a significantly negative correlation between macular choroidal thickness and axial length (R(2)= 0.69; p < 0.001). However, no correlation between serum VEGF and either macular choroidal thickness or axial length was detected in high myopia patients (R(2)= 0.009; p = 0.59; R(2)= 0.00002; p = 0.981).

CONCLUSIONS

Macular choroidal thickness was significantly correlated with aqueous, but not serum, levels of VEGF in highly myopic eyes. Macular choroidal thickness may be of predictive value for identifying aqueous VEGF levels in high myopia patients and may, thus, be a useful prognostic modality.