Aqueous vascular endothelial growth factor as a predictor of macular thickening following cataract surgery in patients with diabetes mellitus

Rationale of Basic and Cellular Mechanisms Considered in Updating the Staging System for Diabetic Retinal Disease

Purpose

Hyperglycemia is a major risk factor for early lesions of diabetic retinal disease (DRD). Updating the DRD staging system to incorporate relevant basic and cellular mechanisms pertinent to DRD is necessary to better address early disease, disease progression, the use of therapeutic interventions, and treatment effectiveness.

Design

We sought to review preclinical and clinical evidence on basic and cellular mechanisms potentially pertinent to DRD that might eventually be relevant to update the DRD staging system.

Participants

Not applicable.

Methods

The Basic and Cellular Mechanisms Working Group (BCM-WG) of the Mary Tyler Moore Vision Initiative carefully and extensively reviewed available preclinical and clinical evidence through multiple iterations and classified these.

Main Outcome Measures

Classification was made into evidence grids, level of supporting evidence, and anticipated future relevance to DRD.

Results

A total of 40 identified targets based on pathophysiology and other parameters for DRD were grouped into concepts or evaluated as specific candidates. VEGFA, peroxisome proliferator-activated receptor-alpha related pathways, plasma kallikrein, and angiopoietin 2 had strong agreement as promising for use as biomarkers in diagnostic, monitoring, predictive, prognostic, and pharmacodynamic responses as well as for susceptibility/risk biomarkers that could underlie new assessments and eventually be considered within an updated DRD staging system or treatment, based on the evidence and need for research that would fit within a 2-year timeline. The BCM-WG found there was strong reason also to pursue the following important concepts regarding scientific research of DRD acknowledging their regulation by hyperglycemia: inflammatory/cytokines, oxidative signaling, vasoprotection, neuroprotection, mitophagy, and nutrients/microbiome.

Conclusion

Promising targets that might eventually be considered within an updated DRD staging system or treatment were identified. Although the BCM-WG recognizes that at this stage little can be incorporated into a new DRD staging system, numerous potential targets and important concepts deserve continued support and research, as they may eventually serve as biomarkers and/or therapeutic targets with measurable benefits to patients with diabetes.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Comparison between intravitreal ranibizumab injection and posterior subtenon triamcinolone acetonide injection at time of cataract surgery for prevention of progression of diabetic macular edema

BACKGROUND

The goal of this work is to assess progression of diabetic macular edema (DME) following intravitreal ranibizumab injection compared to subtenon triamcinolone acetonide injection at cataract operation.

METHODS

Retrospective analysis of 73 eyes of 65 participant with DME, with central macular thickness (CMT) ≥ 300 μm. The included eyes were separated into three groups; phacoemulsification with intravitreal Ranibizumab injection group, phacoemulsification with subtenon Triamcinolone acetonide injection group and phacoemulsification only group. Main measures involved best corrected visual acuity (BCVA) one week, one month and three months post-operative. The CMT was compared preoperative and postoperative (one and three months).

RESULTS

After 1 month of operation, there was a statistical substantial distinction in the median of CMT between ranibizumab & control group (p < 0.001), between subtenon TA & control group (p < 0.001) and in ranibizumab and subtenon TA group (p = 0.023). After 3 months, the variance between ranibizumab & control group was considerable (p < 0.0001) and the variance between subtenon TA & control group was considerable (p = 0.030).

CONCLUSIONS

Combined phacoemulsification with intravitreal injections of ranibizumab or subtenon triamcinolone acetonide may prevent further progression in CMT in individuals with DME following cataract operation.

Therapeutic effect of cataract surgery with simultaneous intravitreal injection of aflibercept on diabetic macular edema: An observational study

This study aimed to investigate the therapeutic effect of cataract surgery along with simultaneous intravitreal injection (IVI) of aflibercept on diabetic macular edema (DME). This cohort study enrolled 106 patients aged >40 years with type 2 diabetes mellitus and DME who received cataract surgery from January 1, 2016, to October 31, 2020. The baseline and mean data of the following parameters were collected: age, sex, glycated hemoglobin level, diabetic retinopathy (DR) grading, previous DR treatments including IVI of anti-vascular endothelial growth factor and pan-retinal photocoagulation, intraocular pressure, use of intraocular pressure-lowering medication, central subfield thickness (CST), and log MAR visual acuity (VA). Patients were categorized into 2 groups based on whether they received aflibercept IVI or not during cataract surgery and were compared using the t test and Fisher exact test for continuous and discrete variables, respectively. Beta coefficient and standard error were calculated using multiple linear regression analysis to identify the explanatory variables predictive of the net change of CST and log MAR VA. There was no difference in the net change in CST (15.24 ± 45.07 μm vs 18.62 ± 33.84 μm, P = .772) and log MAR VA (-0.27 ± 0.29 vs -0.37 ± 0.31, P = .215). Gender, glycated hemoglobin level, aflibercept IVI during cataract surgery, and baseline CST did not interfere with the morphological and functional outcomes of DME in cataract surgery. Older age was significantly and independently associated with a greater net change in log MAR VA. Proliferative DR was significantly and independently associated with a greater net change in CST and log MAR VA. A greater baseline log MAR VA was significantly and independently associated with lower net change in log MAR VA. Simultaneous aflibercept IVI for treating DME may not interfere with the functional and tomographic parameters of cataract surgery relative to cataract surgery alone. Factors influencing the outcomes of patients with DME undergoing cataract surgery are as follows: age, baseline DR staging, and baseline VA. Identifying these factors of DME preoperatively may be an important consideration in preventing it from progressing and for improving the overall visual prognosis.

Comparison of VEGF level in tears post phacoemulsification between non-proliferative diabetic retinopathy and non-diabetic patients

Background

Progression of diabetic retinopathy post cataract surgery is related to the increased level of vascular endothelial growth factor (VEGF) in ocular fluid post operatively. The aim of this study was to compare the VEGF level in tears post phacoemulsification between non-proliferative diabetic retinopathy (NPDR) and non-diabetic patients.

Methods

This was a prospective cohort study and was conducted from June 2017 to May 2019. Patients with underlying NPDR who were planned for phacoemulsification were recruited in this study. Non-diabetic patients who were planned for phacoemulsification were included as control group. Tears samples were collected using Schirmer strip two weeks prior to operation, at day (D) 7 and D30 post phacoemulsification. Tears samples were analyzed for VEGF level.

Results

A total of 65 patients were recruited in this study (NPDR: 32 and control: 33). There was significant increase of VEGF levels in tears from pre operation to D7 post phacoemulsification in NPDR (p < 0.001) and control (p < 0.001). There was also significant reduction of tear VEGF level from D7 to D30 post phacoemulsification in both groups (p < 0.001 in NPDR and p = 0.027 in control). The tear VEGF level was significantly higher in NPDR group compared to control at D7 post phacoemulsification (149.4 SD 55.2 pg/mL vs 109.7 SD 48.7 pg/mL, p = 0.003).

Conclusion

VEGF level in tears showed significant elevation post early cataract surgery in NPDR compared to non-diabetic patient. Therefore, tears VEGF level may provide as a non-invasive method to predict progression of diabetic retinopathy post operation among diabetic patients.

Diabetic retinopathy and diabetic macular oedema pathways and management: UK Consensus Working Group

The management of diabetic retinopathy (DR) has evolved considerably over the past decade, with the availability of new technologies (diagnostic and therapeutic). As such, the existing Royal College of Ophthalmologists DR Guidelines (2013) are outdated, and to the best of our knowledge are not under revision at present. Furthermore, there are no other UK guidelines covering all available treatments, and there seems to be significant variation around the UK in the management of diabetic macular oedema (DMO). This manuscript provides a summary of reviews the pathogenesis of DR and DMO, including role of vascular endothelial growth factor (VEGF) and non-VEGF cytokines, clinical grading/classification of DMO vis a vis current terminology (of centre-involving [CI-DMO], or non-centre involving [nCI-DMO], systemic risks and their management). The excellent UK DR Screening (DRS) service has continued to evolve and remains world-leading. However, challenges remain, as there are significant variations in equipment used, and reproducible standards of DMO screening nationally. The interphase between DRS and the hospital eye service can only be strengthened with further improvements. The role of modern technology including optical coherence tomography (OCT) and wide-field imaging, and working practices including virtual clinics and their potential in increasing clinic capacity and improving patient experiences and outcomes are discussed. Similarly, potential roles of home monitoring in diabetic eyes in the future are explored. The role of pharmacological (intravitreal injections [IVT] of anti-VEGFs and steroids) and laser therapies are summarised. Generally, IVT anti-VEGF are offered as first line pharmacologic therapy. As requirements of diabetic patients in particular patient groups may vary, including pregnant women, children, and persons with learning difficulties, it is important that DR management is personalised in such particular patient groups. First choice therapy needs to be individualised in these cases and may be intravitreal steroids rather than the standard choice of anti-VEGF agents. Some of these, but not all, are discussed in this document.

Outcomes in Patients with Diabetic Macular Edema Requiring Cataract Surgery in VISTA and VIVID Studies

PURPOSE

To evaluate the impact of cataract surgery on visual and anatomic outcomes in patients with diabetic macular edema treated with intravitreal aflibercept injection (IAI) or laser control and who did not require rescue therapy.

DESIGN

Post hoc analysis of 2 phase 3 trials, Study of Intravitreal Aflibercept Injection in Patients with Diabetic Macular Edema (VISTA) and Intravitreal Aflibercept Injection in Vision Impairment Due to DME (VIVID).

PARTICIPANTS

Fifty-four patients (laser treatment, n = 11; IAI, n = 43) who underwent cataract surgery during the study period.

METHODS

In VISTA and VIVID, patients received IAI 2 mg every 4 weeks, IAI 2 mg every 8 weeks after 5 monthly doses, or laser control through week 100. Starting at week 24, if rescue treatment criteria were met, IAI patients received laser therapy, and laser therapy patients received IAI 2 mg every 8 weeks (after 5 monthly doses). Patients who received rescue treatment before cataract surgery were excluded.

MAIN OUTCOME MEASURES

Best-corrected visual acuity (BCVA) and central retinal thickness (CRT) in the laser control and pooled IAI groups before and after cataract surgery.

RESULTS

The cumulative incidence of cataract surgery did not depend on treatment group assignment (rate ratio, = 1.517; 95% confidence interval, 0.782-2.944; P = 0.2174). At the last study visit before surgery, BCVA was 62.2 and 56.9 letters and CRT was 342 μm and 301 μm in the laser control and IAI groups, respectively. At the first study visit after cataract surgery, BCVA was improved significantly in both the laser control and IAI groups to 73.5 letters (P = 0.010 compared with last visit before surgery) and 67.2 letters (P < 0.001 compared with last visit before surgery), respectively. Corresponding change in CRT was a modest increase to 364 μm (P > 0.05 compared with last visit before surgery) and 359 μm (P = 0.013 compared with last visit before surgery), respectively.

CONCLUSIONS

Incidence of cataract surgery was similar in both treatment groups. Despite a modest worsening in CRT after cataract surgery, BCVA was improved in both treatment groups.

Aqueous Humor Cytokines and Long-Term Response to Anti-Vascular Endothelial Growth Factor Therapy in Diabetic Macular Edema

PURPOSE

To determine the association of aqueous humor cytokine concentrations with long-term treatment response to anti-vascular endothelial growth factor (VEGF) agents in diabetic macular edema (DME).

DESIGN

Retrospective case series.

METHODS

Pooled data of aqueous humor cytokine concentrations collected at baseline and 2-month follow-up (2 injections) for treatment-naïve eyes with center-involving DME previously enrolled in a prospective study were reviewed. Subjects receiving intravitreal anti-VEGF injections outside of study protocol as per standard of care were classified into Responders versus Nonresponders based on qualitative assessment of optical coherence tomography for persistence of DME at longitudinal follow-up visits.

RESULTS

Of the 41 eyes, 85% were classified as Responders with a significant decline in baseline central subfield thickness and macular volume (P values < .001), and 15% were identified as Nonresponders to anti-VEGF therapy over 51.4 ± 18.7 months of follow-up. No significant difference in baseline aqueous humor VEGF concentration was noted, while at the 2-month follow-up the Nonresponder group had a significantly higher VEGF concentration compared with the Responder group (451.5 ± 690.9 pg/mL vs 113.7 ± 211.4 pg/mL; P = .02). The Responder group also demonstrated a significant decline from baseline to 2-month follow-up in concentration of intercellular adhesion molecule-1 (P < .001), interleukin-10 (P = .041), monocyte chemotactic protein-1 (P = .046), placental growth factor (P = .027), and transforming growth factor-β2 (P = .017).

CONCLUSIONS

Aqueous humor cytokine concentrations serve as an early biomarker for long-term response to anti-VEGF therapy and may enable more effective treatment regimens that improve anatomical outcomes in eyes with DME.

A longitudinal study of choroidal changes following cataract surgery in patients with diabetes

OBJECTIVE

To study the structural changes in the choroid of diabetic patients following cataract surgery, using choroidal vascularity index and choroidal thickness.

METHODS

A prospective case-control study was conducted in 18 diabetic and 18 non-diabetic patients undergoing cataract surgery (phacoemulsification) in one eye. Enhanced depth imaging optical coherence tomography images were obtained before and after surgery. Niblack's image binarization of images was performed to derive the choroidal vascularity index. Independent sample T-test compared the differences of choroidal vascularity index and choroidal thickness between diabetic and non-diabetic patients.

RESULTS

The baseline choroidal vascularity index was significantly lower in diabetic patients for both operated (mean difference vs non-diabetic: 0.0184, 95% CI: 0.004-0.0324, p = 0.012) and non-operated (mean difference vs non-diabetic: 0.0145, 95% CI: 0.003-0.0256, p = 0.012) eyes. Choroidal thickness increased following cataract surgery (diabetes: mean difference = 12.4, 95% CI: 0.70-24.0, adjusted p = 0.036; non-diabetic: mean difference = 21.0, 95% CI: 4.39-37.6, adjusted p = 0.011).

CONCLUSION

Diabetic patients have reduced choroidal vascularity index than non-diabetic patients, suggestive of possible reduction in choroidal vascularity in diabetes. Choroidal thickness increased following cataract surgery in both diabetic and non-diabetic patients.

A Systematic Review and Meta-Analysis of Clinical Outcomes of Intravitreal Anti-VEGF Agent Treatment Immediately after Cataract Surgery for Patients with Diabetic Retinopathy

Aims

To examine possible benefits of intravitreal anti-vascular endothelial growth factor (VEGF) agent treatment immediately after cataract surgery for patients with diabetic retinopathy (DR).

Methods

A comprehensive literature search was performed using the Cochrane collaboration methodology to identify randomized controlled trials (RCTs) and comparative studies of cataract surgery with or without anti-VEGF agent treatment for any diabetic retinopathy. Meta-analyses were performed for clinical outcome parameters including changes in macular thickness (MT), best-corrected visual acuity (BCVA), incidence of diabetic retinopathy and maculopathy progression, laser treatment rate, and other complications.

Results

Nine RCTs and 3 nonrandomized comparative studies were identified and used for comparing cataract surgery with intravitreal bevacizumab (IVB) or intravitreal ranibizumab (IVR) treatment (338 eyes, intervention group) to cataract surgery alone (329 eyes, control group). Analysis of all data showed that the mean BCVA at 1 week postoperatively had no statistically significant difference in the two groups, but at 1, 3, and 6 months postoperatively, the mean BCVA was statistically significantly better in the anti-VEGF treatment group than that in cataract surgery alone group. Analysis of all data showed that the mean MT was statistically significantly less in the anti-VEGF treatment group at 1 week and 1, 3, and 6 months postoperatively (P=0.05, P=0.006, P=0.0001, and P=0.0001, respectively); but postoperative clinical outcomes were differentiated from the type of anti-VEGF agents, IVB or IVR, and the existing macular edema preoperatively. Intravitreal anti-VEGF agent treatment statistically significantly reduced the incidence of diabetic retinopathy progression and maculopathy progression compared to the control group (P=0.0003, P < 0.00001, respectively).

Conclusion

IVB or IVR treatment immediately after cataract surgery may represent a safe and effective strategy to prevent postoperative macular thickening or reduce macular edema and result in greater mean improvements in visual acuity for diabetic patients.

Developing a comprehensive, culturally sensitive conceptual framework of health domains in Singapore

The increasing focus of healthcare systems worldwide on long-term care highlights the need for culturally sensitive Health-Related Quality of Life instruments to accurately capture perceived health of various populations. Such instruments require a contextualized conceptual framework of health domains, which is lacking in some socio-cultural contexts. We developed a comprehensive and culturally sensitive conceptual framework of health domains relevant to the Singaporean population. We recruited Singaporeans/ permanent residents, English/ Chinese-speaking, with/ without chronic illnesses to participate in focus group discussions (FGDs) and in-depth interviews (IDIs). We elicited health areas participants perceived to be important for them to be happy and satisfied with life. To encourage spontaneous emergence of themes, we did not specify any aspect beyond the broad domains of Physical, Mental, and Social health so as not to limit the emergence of new themes. Themes from the transcripts were distilled through open coding (two independent coders), then classified into more abstract domains (each transcript coded independently by two coders from a pool of six coders). From October 2013 to August 2014, 121 members of the general public participated in 18 FGDs and 13 IDIs (44.6% males, mean age: 53.3 years 77% Chinese, 9% Malay, 12% Indian, 63% with chronic illness) while 13 healthcare workers participated as patient-proxies in three FGDs. Thematic analysis identified 27 domains. The 15 physical domains included physical appearance, energy, physical fitness, and health and resistance to illness. The nine mental domains included emotions, self-esteem, and personal freedom. The three social domains were social contact, social relationships, and social roles. This conceptual framework reflected physical, mental, and social dimensions of well-being, suggesting that the Singapore population's views on health support the World Health Organization's definition of health as "a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity".

Role of combined phacoemulsification and intravitreal injection of bevacizumab in prevention of postoperative macular edema in non-proliferative diabetic retinopathy

Purpose

To evaluate the role of combined phacoemulsification and intravitreal injection of bevacizumab in prevention of postoperative diabetic macular edema (DME) in patients with no diabetic retinopathy or non-proliferative diabetic retinopathy (NPDR) and without macular edema.

Methods

In a prospective randomized clinical trial, 71 eyes from 71 diabetic patients with no diabetic retinopathy or mild NPDR and with central macular thickness (CMT) of less than 300 μm were enrolled and were randomized into two groups: combined phacoemulsification and intravitreal bevacizumab injection group and only phacoemulsification group. Our primary outcome measures included best corrected visual acuity (BCVA), CMT, and total macular volume (TMV) before and after (1 month and 3 months) the cataract surgery.

Results

The two groups did not show any significant difference in terms of baseline BCVA, age, CMT, stage of diabetic retinopathy. While the bevacizumab group showed lower CMT one month after the surgery compared to control group (267.3 ± 31.8 and 293.6 ± 53.7, respectively, P = 0.019), this difference did not remain significant 3 months after surgery (264.5 ± 21.9 and 291.4 ± 79.8, P = 0.089). The TMV and BCVA in the two groups showed no significant difference one month or 3 months after surgery. Considering our definition of post-cataract surgery diabetic macular edema (PME) in this study [CMT >300 μm using spectral domain optical coherence tomography (SD-OCT)], there was no significant difference between the incidence of PME at 1 month and at 3 months after surgery.

Conclusions

Although the intravitreal injection of bevacizumab during phacoemulsification would result in decreased macular thickness in patients with no diabetic retinopathy or NPDR and without macular edema in the early postoperative period, this effect would no longer persistent at 3 months. In addition, the BCVA and TMV showed no significant difference between the two groups at any time during follow-up period.

[Evidence-based medicine: opportunities of the Propensity Score Matching (PSM) method in eliminating selection bias in retrospective neurosurgical studies]

To date, a large amount of retrospectively collected data about treatment of neurosurgical pathology have been accumulated. Modern methods of medical statistics are necessary for correct interpretation of the data. The article purpose is to demonstrate application of one of the modern methods, Propensity Score Matching (PSM), in neurosurgery. The use of PSM avoids misinterpretation of retrospectively collected data and obviates errors in planning further prospective studies. For the past 10 years, the number of published international PSM-based studies has increased more than 10-fold, with the number of articles by Russian authors accounting for less than 0.2%. In line with the tendencies of international studies, application of PSM in analysis of retrospectively collected data will enable testing of a number of hypotheses and correct planning of prospective randomized studies.

Fabrication, Characterization and Cytotoxicity of Spherical-Shaped Conjugated Gold-Cockle Shell Derived Calcium Carbonate Nanoparticles for Biomedical Applications

The evolution of nanomaterial in science has brought about a growing increase in nanotechnology, biomedicine, and engineering fields. This study was aimed at fabrication and characterization of conjugated gold-cockle shell-derived calcium carbonate nanoparticles (Au-CSCaCO3NPs) for biomedical application. The synthetic technique employed used gold nanoparticle citrate reduction method and a simple precipitation method coupled with mechanical use of a Programmable roller-ball mill. The synthesized conjugated nanomaterial was characterized for its physicochemical properties using transmission electron microscope (TEM), field emission scanning electron microscope (FESEM) equipped with energy dispersive X-ray (EDX) and Fourier transform infrared spectroscopy (FTIR). However, the intricacy of cellular mechanisms can prove challenging for nanomaterial like Au-CSCaCO3NPs and thus, the need for cytotoxicity assessment. The obtained spherical-shaped nanoparticles (light-green purplish) have an average diameter size of 35 ± 16 nm, high carbon and oxygen composition. The conjugated nanomaterial, also possesses a unique spectra for aragonite polymorph and carboxylic bond significantly supporting interactions between conjugated nanoparticles. The negative surface charge and spectra absorbance highlighted their stability. The resultant spherical shaped conjugated Au-CSCaCO3NPs could be a great nanomaterial for biomedical applications.

Management of macular oedema in diabetic patients undergoing cataract surgery

PURPOSE OF REVIEW

The aim of this study was to describe all the treatment modalities used to prevent and manage macular oedema in diabetic patients undergoing cataract surgery.

RECENT FINDINGS

Topical NSAIDs have been proposed to be an effective strategy to prevent postsurgical macular oedema (PME) in diabetic patients. The prophylactic use of intravitreal antivascular endothelial growth factors (anti-VEGF) drugs and steroids in these patients, even if effective, brings some concerns with regard to possible side effects. By contrast, in patients with a diagnosis of diabetic macular oedema (DME) at the time of cataract surgery, intravitreal therapy, both with anti-VEGF drugs and steroids, appears to be the best approach in order to control PME and achieve a good visual outcome.

CONCLUSION

All diabetic patients undergoing cataract surgery should be treated with topical NSAIDs to prevent PME. Intravitreal anti-VEGF drugs and steroids, combined with cataract surgery, should be reserved for patients with preexisting DME.

Influence of uncomplicated phacoemulsification on central macular thickness in diabetic patients: a meta-analysis

OBJECTIVE

To evaluate the effect of uncomplicated phacoemulsification on central macular thickness (CMT) and best corrected visual acuity (BCVA) in both diabetic patients without diabetic retinopathy (DR) and diabetic patients with mild to moderate non-proliferative diabetic retinopathy (NPDR).

METHODS

Potential prospective observational studies were searched through PubMed and EMBASE. Standardized mean difference (SMD) and 95% confidence interval (CI) for changes in CMT and BCVA were evaluated at postoperative 1, 3 and 6 months. The pooled effect estimates were calculated in the use of a random-effects model.

RESULTS

A total of 10 studies involving 190 eyes of diabetic patients without diabetic retinopathy and 143 eyes of diabetic patients with NPDR were identified. CMT values demonstrated a statistically significant increase after uncomplicated phacoemulsification at 1 month (SMD, -0.814; 95%CI, -1.230 to -0.399), 3 months (SMD, -0.565; 95%CI, -0.927 to -0.202) and 6 months (SMD, -0.458; 95%CI, -0.739 to -0.177) in diabetic patients with NPDR. There was no statistical difference in CMT values at postoperative 1 month (SMD, -1.206; 95%CI, -2.433 to 0.021)and no statistically significant increase in CMT values at postoperative3 months (SMD, -0.535; 95%CI, -1.252 to 0.182) and 6 months (SMD, -1.181; 95%CI, -2.625 to 0.263) in diabetic patients without DR.BCVA was significantly increased at postoperative 1 month (SMD, 1.149; 95%CI, 0.251 to 2.047; and SMD,1.349; 95%CI, 0.264 to 2.434, respectively) and 6 months (SMD, 1.295; 95%CI, 0.494 to 2.096; and SMD, 2.146; 95%CI, 0.172 to 4.120, respectively) in both diabetic patients without DR and diabetic patients with NPDR. Sensitivity analysis showed that the results were relatively stable and reliable.

CONCLUSION

Uncomplicated phacoemulsification in diabetic patients with mild to moderate NPDR seemed to influence significantly the subclinical thickening of the macular zones at postoperative 1, 3 and 6 months compared with diabetic patients without DR. BCVA was significantly improved in both diabetic patients without DR and diabetic patients with mild to moderate NPDR.

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.

Biomarkers in diabetic retinopathy and the therapeutic implications

The main problem both in type 1 (T1DM) and type 2 (T2DM) diabetes is the development of chronic vascular complications encompassing micro- as well as macrocirculation. Chronic complications lower the quality of life, lead to disability, and are the cause of premature death in DM patients. One of the chronic vascular complications is a diabetic retinopathy (DR) which leads to a complete loss of sight in DM patients. Recent trials show that the primary cause of diabetic retinopathy is retinal neovascularization caused by disequilibrium between pro- and antiangiogenic factors. Gaining knowledge of the mechanisms of action of factors influencing retinal neovascularization as well as the search for new, effective treatment methods, especially in advanced stages of DR, puts special importance on research concentrating on the implementation of biological drugs in DR therapy. At present, it is antivascular endothelial growth factor and antitumor necrosis factor that gain particular significance.

Soluble mediators of diabetic macular edema: the diagnostic role of aqueous VEGF and cytokine levels in diabetic macular edema

Diabetic macular edema (DME) is a significant cause of vision loss and represents an important clinical and public health problem. It is characterized by breakdown of the blood retinal barrier with fluid accumulation in the sub-retinal and intra-retinal spaces. Although several hypotheses exist for the causes of diabetic macular edema, specific molecular mechanisms remain unclear. Current thinking includes the role of vascular endothelial growth factor (VEGF) and inflammatory cytokines in vascular permeability. We review studies showing a relationship between elevated aqueous VEGF, monocyte chemoattractant protein -1, interleukin 6, or interleukin 8 in association with DME and as predictors of DME. The presence of mediators in both the angiogenesis and inflammatory pathways data suggest a multifactorial model for the development of DME. Further studies targeting individual cytokine activity will be important to our understanding of the pathogenesis and treatment.

[Diabetic maculopathy. Diagnosis and treatment]

Due to demographic change the incidence of diabetic retinopathy has risen in spite of new facilities and prevention campaigns and is still one of the leading causes of blindness in Germany. The combination of focal/grid laser photocoagulation and an intravitreal anti-VEGF (vascular endothelial growth factor) regimen is the first line approach for clinically significant macular edema with foveal involvement and is evidence-based. Vitreomacular interface abnormalities can be effectively treated by modern vitreomacular surgery. Unfortunately, no proven treatment modality can be provided for ischemic maculopathy. The management of systemic risks factors, such as hyperglycemia and arterial hypertension, remains a task of great importance despite all modifications and increase of knowledge during recent years. Innovative developments in the field of intravitreal pharmacotherapy have opened up new vistas. There are good prospects that modern ophthalmology will not be limited to preserving visual function but to allow improvements and consequently enhance health-related quality of life for diabetic patients.