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BACKGROUND: To report the risk of exudation recurrence and long-term outcomes in patients with choroidal neovascularization secondary to angioid streaks, according to its morphology and characteristics by optical coherence tomography angiography. METHODS: Retrospective analysis of electronic medical records from three hospitals. We enrolled patients with a clinical diagnosis of angioid streaks choroidal neovascularization that had a minimum follow-up of 12 months. From each record, we extracted general demographic data, best corrected visual acuity (baseline, before and after each disease recurrence and last on file), type of treatment, time between last intravitreal injection and disease recurrence, and classification of the neovascular lesion morphology by optical coherence tomography, and optical coherence tomography angiography. Patients with myopic choroidal neovascularization were used as controls. Interobserver agreement was assessed with a Cohen-Kappa test. The Odds ratio was calculated with a chi2 test for significance. Visual acuity change through time was evaluated with an ANOVA for repeated measurements with an alpha value of 0.05 for statistical significance. RESULTS: We enrolled 30 patients in the study group and 14 in the control group. In the study group, the baseline and final BCVA were 0.861 ± 0.59 and 1.095 ± 0.61 logMAR (p = 0.1) respectively. CONTROL GROUP: 1.045 ± 0.57 and 0.617 ± 0.53 logMAR (p < 0.05). In the study group, the predominant CNV type by OCTA was mixed (37%), and interlacing (57%) in the control group. Mixed and cog-wheel patterns at baseline had increased Odds for recurrence in the study group (p = 0.09). Patients in the study group required more intravitreal injections on each recurrence episode to achieve disease control (3.5 ± 1.5 vs.1.4 ± 0.2, p < 0.01). CONCLUSIONS: The benefits of anti-VEGF treatment are lost over time in patients with angioid streaks and CNV. Lesion characteristics by optical coherence tomography angiography could help physicians predict the risk of recurrence. TRIAL REGISTRATION: Retrospective registered, and IRB approved.

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PURPOSE: The purpose of this study was to assess the role of combined surgical treatment of therapeutic penetrating keratoplasty and pars plana vitrectomy in the anatomical and functional outcome of infectious keratitis endophthalmitis. METHODS: This study reviewed the medical records of 4 participating centers in the United States and Mexico. This study included patients with a clinical diagnosis of infectious keratitis endophthalmitis who had been treated with an early therapeutic penetrating keratoplasty and pars plana vitrectomy as the main treatment for endophthalmitis. From each medical record, the study retrieved demographic data, relevant medical and drug history, baseline clinical manifestation of endophthalmitis, best-corrected visual acuity, and the need for enucleation/evisceration for the control of the infection or any other reason through the follow-up. RESULTS: The study included 48 patients (50.15 ± 20.6 years). The mean follow-up time was 13 ± 0.5 months. The mean best-corrected visual acuity at baseline was 2.1 ± 0.25 logarithm of the minimum angle of resolution. At month 12 was 2.09 ± 0.61 logarithm of the minimum angle of resolution ( P = 0.9). The overall prevalence of enucleation/evisceration was 8.3% (95% confidence interval: 2.32%-19.98%). The prevalence of a vision of no-light perception was 20.8% (95% confidence interval: 2.32%-19.98%). CONCLUSIONS: Combined surgery for severe cases of infectious keratitis endophthalmitis eradicates the infection in most cases, while significantly improving the overall outcomes.

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PURPOSE: To expand the knowledge regarding the clinical presentation of Kocuria endophthalmitis. METHODS: We included six cases of Kocuria endophthalmitis between January 2018 and December 2020. From all cases, we collected general demographic data, relevant medical, ophthalmological history, microbiological and antibiotic sensitivity results. All cases had a minimum follow-up of 9 months. All cases were treated with intravitreal moxifloxacin and dexamethasone and pars plana vitrectomy. Undiluted vitreous, corneal, conjunctival, and aqueous samples were cultured and analyzed with the Vitek 2 system. RESULTS: The prevalence of Kocuria endophthalmitis was 6%. (95%CI: 2.26%-12.73%). The mean age at diagnosis was 60.5 ± 15.5 years. All patients had poor visual acuity, severe pain, and severe conjunctival hyperemia at diagnosis. Only one case had a significant improvement in visual acuity at the end of the follow-up. CONCLUSION: Kocuria spp are an emerging cause of endophthalmitis and should be considered as part of the differential diagnosis.

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PURPOSE: To assess the risk for capsular rupture during routine phacoemulsification in patients with a history of anti-VEGF injections and other possible risk modifiers such as treatment patterns, type of anti-VEGF agent, and experience of the surgeon, among others. METHODS: This study reviewed the medical records of 11,129 patients from 7 different hospitals in 5 countries. The study included 939 patients that underwent routine phacoemulsification and had a history of anti-VEGF therapy. We excluded patients with known risk factors for capsular rupture, as well as patients with a history of other retinal procedures. The study extracted data regarding general demographics, the number of previous injections, type of anti-VEGF agent, details of cataract surgery, and anti-VEGF treatment patterns. RESULTS: Overall prevalence of posterior capsular rupture: 7.45% (95% CI: 5.9-9.32%). The mean number of injections per patient was 3.37 ± 2.8. More than 50% of the patients received their last anti-VEGF injection within three months before cataract surgery. The complication rate during intravitreal injections was 1.07%. In the univariate analysis, the experience of the cataract surgeon (inexperience surgeons; OR: 2.93) and the history of prior anti-VEGF therapy (OR: 1.77) were significant risk indicators for PCR (p < 0.05). However, after controlling for age in the multivariate analysis, the trend did not reach a statistical significance. CONCLUSION: The risk for capsular rupture is higher in patients with a history of intravitreal anti-VEGF injections.

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BACKGROUND: Despite the constant refinement of techniques and surgical aids, extremely large and refractory macular holes continue to have poor surgical outcomes with the current standard of care. The objective of the present study is to assess the anatomical and functional outcomes, as well as the structural change through time, of the optical coherence tomography of patients with refractory macular holes treated with a full-thickness autologous retinal transplant. METHODS: Prospective, case series. We include patients with a clinical diagnosis of refractory macular holes with a minimum diameter of at least 500 µm. All the patients had a comprehensive ophthalmological examination, which included a best-corrected visual acuity assessment, fundus examination, and optical coherence analysis. All the patients underwent a 23-gauge pars plana vitrectomy with a full-thickness retinal transplant and silicone oil tamponade (5000 cs<). Follow-up was done at 1, 3, 6, and 12 months. Statistical analysis was done with a test for repeated measurements and Bonferroni correction, with an alpha value of 0.05 for statistical significance and a Mann-Whitney U test for nonparametric continuous variables. RESULTS: We enrolled 13 eyes from 13 patients (mean age: 67.15 years) with refractory macular holes, with a mean base diameter of 1615.38 ± 689.19 µm and a minimum diameter of 964.08 ± 709.77 µm. The closure rate after 12 months of follow-up was 76.92%. Six patients with a closed macular hole at the end of the follow-up had complete recovery of the myoid/ellipsoid layer. The remaining showed a 44.9% reduction of the initial gap. Most patients formed a pseudofovea and normalization of the internal retinal layers. Despite a positive trend toward visual recovery (p = 0.034), after the correction of the alpha value, the change lost its statistical significance. During follow-up, one patient developed mild proliferative vitreoretinopathy and epiretinal membrane without anatomical or functional consequences. CONCLUSIONS: An autologous full-thickness retinal transplant may improve the anatomical and structural outcome of patients with refractory macular holes. The full safety profile of this new technique is still unknown. More studies are needed in order to assess functional changes through time.

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PURPOSE: To evaluate the combination of fundus autofluorescence results with several clinical and structural variables into mathematical indexes to enhance their ability to predict visual and anatomical changes after the antivascular endothelial growth factor loading dose. METHODS: Patients with diabetic macular edema were enrolled. Each patient had a comprehensive ophthalmological examination, contrast sensitivity, optical coherence tomography, and fundus autofluorescence assessment. All patients received three monthly doses of ziv-aflibercept and were followed each month for response assessment. Autofluorescence was classified according to its level into five grades. The grades were combined with other variables (best-corrected visual acuity, contrast sensitivity, central macular thickness, macular cube volume, and macular cube average thickness) into normalized indexes. Statistical assessment was done using a Spearman's rank correlation coefficient, linear regression, and interobserver-agreement analysis. RESULTS: There was a strong correlation between the fundus autofluorescence/baseline best-corrected visual acuity index and the fundus autofluorescence/contrast-sensitivity index at baseline with the best-corrected visual acuity after the third dose of ziv-aflibercept (rs = -0.78, p = .000 and rs = -0.68, p = .0009 respectively). The fundus autofluorescence/baseline best-corrected visual acuity index and the fundus autofluorescence/contrast-sensitivity index, both at baseline had a mild correlation with the macular volume at 1 month of follow-up (rs = 0.56, p = .008 and (rs = 0.64, p = .002, respectively). CONCLUSION: This study suggests that it is possible to combine fundus autofluorescence results with functional and structural variables into normalized indexes that could potentially predict outcomes after antivascular endothelial growth factor loading dose in patients with diabetic macular edema.

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PURPOSE: To propose a method for quantification of vitreous hemorrhages (VH) termed minimum image gain (MIG). Therefore, to obtain MIG measurements in patients with VH and to compare them to normal controls; to compare results between graders; and to obtain and compare MIG from two different ultrasound systems. METHODS: Retrospective and cross-sectional, observational, and comparative study performed in two parts: Part 1) Retrospective comparison of MIG in VH vs controls by two experienced graders, with intra/inter-observer variability: MIG technique is described. MIG is performed retrospectively in two groups, VH patients and normal controls. Groups are compared with independent samples t-test. Intra- and interobserver variability between graders was obtained. Part 2) Cross-sectional analysis of variability from nonexperienced graders and with different ultrasound systems: MIG is performed in cross-sectional measurements of VH patients, by two unexperienced graders, and with two ultrasound systems. Interobserver variability and Bland-Altman plot with levels of agreement (LoA) were obtained. RESULTS: Part 1: 50 patients with VH resulted in mean MIG: 52.8 dB; 34 controls resulted in mean MIG: 77.97 dB. Independent samples t-test resulted in a statistical significant difference. Intra- and inter-observer variability resulted in an almost perfect agreement between experienced graders. Part 2: 63 patients with VH, mean MIG: 56.19 dB. Inter-observer variability resulted in a very high agreement between unexperienced observers. LoA resulted in a statistical difference between the two ultrasound systems. CONCLUSION: MIG may provide an objective and reproducible way to quantify vitreous hemorrhage density and potentially any vitreous humor opacity. Agreement is high even with unexperienced graders. However, the two ultrasound systems analyzed may not be interchangeable.

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PURPOSE: We describe the functioning of a novel device, aimed to assess patient head position after a pneumatic retinopexy. METHODS: We enrolled patients with the clinical diagnosis of rhegmatogenous retinal detachment. All patients were asked to wear a specially designed headband with a monitoring device composed of an accelerometer, gyroscope, and magnetometer, powered by a 3.7V lithium battery. Every 200 ms, the device measured neck flexion and extension, left and right rotation, and left and right flexion. Patients were asked to come back the next morning for follow-up and headband retrieving. RESULTS: The device was worn an average of 19.17 ± 2.1 hours and performed a mean number of 57,670 ± 8663 measurements without power failures or program errors. An acceptable head position was kept for a mean of 3.33 ± 1.8 hours. The hardest axis to maintain was the right and left flexion of the neck (5.5 ± 2.54 hours of acceptable positioning). CONCLUSION: Real-time monitoring of patient head position after a vitreoretinal procedure is feasible. Maintaining a fixed head position for more than 5 consecutive hours is difficult to achieve and physicians should consider this difficulty when planning treatment. TRANSLATIONAL RELEVANCE: In addition to a significant improvement to the basic design of similar devices, our device allows for assessment of patient adherence to postoperative instructions objectively for the first time to our knowledge. This information could be used in the future to elaborate more detailed position nomograms to improve outcomes.

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We report the trans-operative approach and short-term outcome of a patient who suffered a traumatic avulsion of the cilioretinal artery branch during the surgical management of a cilioretinal arterial branch occlusion (CRABO) with intraocular embolectomy. A patient with acute CRABO underwent a pars plana vitrectomy with in situ embolectomy. The blocked artery was incised using 25 gauge vertical scissors, and embolus manipulation was done using microsurgical forceps. During embolus extraction, the occluded cilioretinal artery and its branch were inadvertently avulsed and torn with subsequent intense bleeding. Laser and endodiathermy were used for acute hemostasis. The maneuvers created an unintended retinochoroidal anastomosis. Visual field improvement was noted 3 months after the surgery. In the event of a complicated surgical embolectomy with the avulsion of the artery, the formation of a retinochoroidal anastomosis and reperfusion of the occluded may occur along with the improvement of visual fields in some cases.

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PURPOSE: To determine the effect achieved from a single dose of anti-VEGF treatment switch, in patients with nAMD previously treated with bevacizumab, switched to either aflibercept or ranibizumab, and to compare the response between aflibercept and ranibizumab. METHODS: In retrospective, observational, and comparative study, patients were divided into two groups: Group 1, patients switched to aflibercept; Group 2, patients switched to ranibizumab. Paired samples t test was performed to measure differences in central macular thickness (CMT). To compare whether there were differences between groups mixed-design ANOVA was used. RESULTS: In Group 1, CMT changed from 360.51 to 260.16 µm, presenting a significant mean difference from PreSwitch to PostSwitch of 100.34 µm (p = 0.002, paired samples t test). In Group 2, CMT changed from 366.33 to 260.72 µm, showing a significant difference from PreSwitch to PostSwitch of 105.61 µm (p ≤ 0.000, paired samples t test). The mixed-design ANOVA compared both groups and resulted in a nonsignificant value of 0.90. CONCLUSION: The effect achieved from a single dose in patients switched to aflibercept or ranibizumab reduced significantly CMT measurements. Comparing aflibercept and ranibizumab, the effect appears to be similar in both drugs, in terms of reduction of CMT.

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PURPOSE: To report a case of occlusive retinal vasculopathy, secondary to hyperhomocysteinemia. OBSERVATIONS: A 43-year-old male was examined at the retina outpatient clinic due to complaints of bilateral decrease in visual acuity. The patient underwent a comprehensive ophthalmological examination, wide-field fundus photographs and fluorescein angiography, as well as spectral domain optical coherence tomography with enhanced-deep imaging. The patient had a significant medical history of chronic kidney disease and progressive bilateral vision loss over the last two years, which worsened in the left eye during the past 3 months. Fundus examination revealed a vitreous hemorrhage in the left eye and bilateral proliferative retinopathy. Blood glucose and systemic blood pressure were unremarkable. Plasma homocysteine was reported at >500 µmol/L, which is higher than the corrected reference range by age. CONCLUSION AND IMPORTANCE: Hyperhomocysteinemia is a rare but well-known disease, capable of accelerating atherosclerotic disease and generating a prothrombotic state that can lead to multiple systemic complications. Despite its low incidence, the disease should be part of the differential diagnosis in patients with bilateral proliferative retinopathy, in the absence of diabetes mellitus and systemic hypertension.

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ABSTRACT We report the trans-operative approach and short-term outcome for a patient who suffered a traumatic avulsion of the cilioretinal artery branch during the surgical management of a cilioretinal arterial branch occlusion with intraocular embolectomy. The patient underwent a pars plana vitrectomy with in situ embolectomy. The blocked artery was incised using 25 Ga vertical scissors, and embolus manipulation was performed using microsurgical forceps. During embolus extraction, the occluded cilioretinal artery and its branch were inadvertently avulsed and torn with subsequent intense bleeding. Laser and endodiathermy were used for acute hemostasis. The maneuvers created an unintended retinochoroidal anastomosis. Visual-field improvement was noted three months after the surgery. In the event of a complicated surgical embolectomy with the avulsion of the artery, the formation of a retinochoroidal anastomosis and reperfusion of the occluded artery may occur along with the improvement of the visual field in some cases.

RESUMO Relatamos a abordagem transoperatória e o desfecho em curto prazo de um paciente que sofreu uma avulsão traumática do ramo da artéria ciliorretiniana durante o tratamento cirúrgico de uma oclusão do ramo arterial ciliorretiniano com embolectomia intraocular. O paciente foi submetido a uma vitrectomia pars plana com embolectomia in situ. A artéria bloqueada foi incisada com uma tesoura vertical de 25 Ga e a manipulação do êmbolo foi feita com pinça microcirúrgica. Durante a extração do êmbolo, a artéria ciliorretiniana ocluída e seu ramo foram inadvertidamente avulsionados e rasgados com sangramento intenso subsequente. Laser e endodiatermia foram utilizados para hemostasia aguda. As manobras criaram uma anastomose retinocoroidiana não intencional. Melhora do campo visual foi observada três meses após a cirurgia. No caso de uma embolectomia cirúrgica complicada com a avulsão da artéria, a formação de uma anastomose retinocoroidiana e reperfusão da artéria ocluída pode ocorrer juntamente com a melhora do campo visual em alguns casos.

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We report the trans-operative approach and short-term outcome for a patient who suffered a traumatic avulsion of the cilioretinal artery branch during the surgical management of a cilioretinal arterial branch occlusion with intraocular embolectomy. The patient underwent a pars plana vitrectomy with in situ embolectomy. The blocked artery was incised using 25 Ga vertical scissors, and embolus manipulation was performed using microsurgical forceps. During embolus extraction, the occluded cilioretinal artery and its branch were inadvertently avulsed and torn with subsequent intense bleeding. Laser and endodiathermy were used for acute hemostasis. The maneuvers created an unintended retinochoroidal anastomosis. Visual-field improvement was noted three months after the surgery. In the event of a complicated surgical embolectomy with the avulsion of the artery, the formation of a retinochoroidal anastomosis and reperfusion of the occluded artery may occur along with the improvement of the visual field in some cases.

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Age-related macular degeneration (AMD) is a well-characterized and extensively studied disease. It is currently considered the leading cause of visual disability among patients over 60 years. The hallmark of early AMD is the formation of drusen, pigmentary changes at the macula, and mild to moderate vision loss. There are two forms of AMD: the "dry" and the "wet" form that is less frequent but is responsible for 90% of acute blindness due to AMD. Risk factors have been associated with AMD progression, and they are taking relevance to understand how AMD develops: (1) advanced age and the exposition to environmental factors inducing high levels of oxidative stress damaging the macula and (2) this damage, which causes inflammation inducing a vicious cycle, altogether causing central vision loss. There is neither a cure nor treatment to prevent AMD. However, there are some treatments available for the wet form of AMD. This article will review some molecular and cellular mechanisms associated with the onset of AMD focusing on feasible treatments for each related factor in the development of this pathology such as vascular endothelial growth factor, oxidative stress, failure of the clearance of proteins and organelles, and glial cell dysfunction in AMD.

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PURPOSE: To describe changes in the retina and choroidal flow by optical coherence tomography angiography (OCT-A) after a single dose of oral sildenafil. METHOD: A case-control study. Patients in the study group received 50 mg of oral sildenafil. Patients in the control group received a sham pill. Retinal and choroidal images were obtained at baseline (before pill ingestion) and 1 hour after ingestion. Central macular and choroidal thickness, choroidal and outer retina flow, and the retinal and choroidal vascular density were compared using a Mann-Whitney U test. RESULTS: Twenty eyes were enrolled into the study group and 10 eyes in the control group. There was a significant difference in central choroidal thickness and outer retina blood flow between groups after 1 hour of sildenafil ingestion (p < 0.01). There were no differences in central macular thickness, choroidal flow, and retinal vascular density among groups. CONCLUSIONS: A single dose of oral sildenafil increases choroidal thickness, probably due to sildenafil-induced vasodilation.

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PURPOSE: To report the incidence and clinical features of patients that experienced un-explained visual loss following silicone oil (SO) removal. METHODS: Multicenter retrospective study of patients that underwent SO removal during 2000-2012. Visual loss of ≥2 lines was considered significant. RESULTS: A total of 324 eyes of 324 patients underwent SO removal during the study period. Forty two (13%) eyes suffered a significant visual loss following SO removal. Twenty three (7.1%) of these eyes lost vision secondary to known causes. In the remaining 19 (5.9%) eyes, the loss of vision was not explained by any other pathology. Eleven of these 19 patients (57.9%) were male. The mean age of this group was 49.2 ± 16.4 years. Eyes that had an un-explained visual loss had a mean IOP while the eye was filled with SO of 19.6 ± 6.9 mm Hg. The length of time that the eye was filled with SO was 14.8 ± 4.4 months. In comparison, eyes that did not experience visual loss had a mean IOP of 14 ± 7.3 mm Hg (p < 0.0002) and a mean tamponade duration of 9.3 ± 10.9 months (p < 0.0001). CONCLUSIONS: An un-explained visual loss after SO removal was observed in 5.9% of eyes. Factors associated with this phenomenon included a higher IOP and longer SO tamponade duration.

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BACKGROUND: To assess the sensitivity, specificity, positive predictive value and negative predictive value of anterior chamber tap for the diagnosis of bacterial endophthalmitis on a population with high prevalence. METHODS: Retrospective, single centre, case series study. We reviewed all medical records with clinical diagnosis of bacterial endophthalmitis in our hospital from January 1st, 2000 to December 31st 2014. From each record, we documented general demographic data, best corrected visual acuity and vitreous and aqueous tap microbiological results. All cases were further divided according to the endophthalmitis aetiology to perform individual calculations of sensitivity, specificity, positive predictive value, negative predictive value, accuracy and prevalence. We used the results of the vitreous tap as the gold standard for diagnosis of bacterial endophthalmitis. We excluded those records in which the aqueous and vitreous samples were not taken simultaneously or had an incomplete microbiological report. Significance were assessed with chi squared statistics, with an alpha value of 0.05 for statistical significance. RESULTS: A total of 190 cases fulfilled the inclusion/exclusion criteria. Positive culture rate from vitreous samples was 64.74%. Positive culture rate from aqueous sample was 32.11%. Bacteria isolated from aqueous samples matched those isolated from vitreous samples 78.68% of the time. The overall sensitivity was 38.21%, specificity: 75.51%, positive predictive value: 79.66%, negative predictive value: 32.74% (p = 0.08). Subgroup analysis showed that anterior chamber taps in cases of post-surgical endophthalmitis had a moderate to low sensitivity (37.73%), high specificity (93%) and high positive predictive value (95%) (p < 0.04). CONCLUSION: The sensitivity and specificity of anterior chamber tap are low and should not be used for critical therapeutic decisions in patients with suspected bacterial endophthalmitis. In cases of post-surgical endophthalmitis, the result of an anterior chamber tap could be used for therapeutic guidance, but only in conjunction with clinical presentation and in the absence of a better method for diagnosis.

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AIM: To assess if the included vascular endothelial growth factor (VEGF) polymorphisms rs3025035, rs3025021 and rs2010963 are associated to proliferative retinopathy in a Mexican population with type 2 diabetes mellitus (T2DM). METHODS: A case-control study was conducted in adult individuals with T2DM associated to proliferative retinopathy or non-proliferative retinopathy from Oct. 2014 to Jun. 2015 from the Retina Department of the Asociation to Prevent Blindness in Mexico. The selected patients were adults with a diagnosis of T2DM ≥5y. All subjects had a comprehensive ocular examination and the classification of the retinopathy severity was made considering the Early Treatment Diabetic Retinopathy Study (ETDRS) standardization protocols. Genomic DNA was extracted from whole fresh blood. All samples were genotyped by qPCR for selected VEGF polymorphisms. Hardy-Weinberg equilibrium was calculated by comparing Chi-square values between the expected and the observed values for genotype counts. RESULTS: In total 142 individuals were enrolled, 71 individuals with T2DM and associated proliferative retinopathy and 71 individuals with non-proliferative retinopathy. One-sided Fisher's exact test was performed for rs3025021 [OR (95% CI)=0.44(0.08-2.2); P=0.25] and rs2010963 [OR (95% CI)=0.63(0.25-1.6); P=0.23]. The minor allelic frequencies obtained were 26% for rs3025021, 10% for rs3025035 and 61% for rs2010963. The pairwise linkage disequilibrium between the three SNP was assessed, and was as follows: rs3025021 vs rs3025035: D'=1.0, r2=0.1043, P≤0.0001; rs3025021 vs rs2010963: D'=0.442, r2=0.0446, P=0.149; rs3025035 vs rs2010963: D'=0.505, r2=0.0214, P=0.142. CONCLUSION: This is the first analysis involving VEGF polymorphisms and proliferative diabetic retinopathy in a Mexican population. A major finding of the present study is that none of the polymorphisms studied was significantly associated with proliferative retinopathy. Based on these results, we can infer that different populations have different associations for the same polymorphisms.

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We aimed to compare the results of pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling, an alternative therapeutic strategy, with those of medical treatment for chronic macular edema. We conducted a review of the literature on the microscopic, anatomical, and functional reasons for performing PPV with ILM peeling in patients with diabetic macular edema (DME). We searched the PubMed database for articles published between 2000 and 2017. We used the medical subject heading "vitrectomy diabetic macular edema" and the keywords "diabetic macular edema", "internal limiting membrane peeling", "pars plana vitrectomy", "diabetic retinopathy", and "optical coherence tomography". Analysis of the literature revealed that cytokines, vascular endothelial growth factor, reactive oxygen species (ROS), and advanced glycation end-products (AGEs) play a unique role in DME. The vitreous cavity serves as a physiological reservoir for all inflammatory molecules. AGE receptors are localized at the footplates of Müller cells and the external limiting membrane (ELM). The footplates of Müller cells are in contact with the ILM, which suggests that they might be responsible for the structural damage (i.e., thickening) observed in the ILM of patients with DME. Therefore, PPV could allow a reduction of cytokines and pro-inflammatory molecules from the vitreous cavity. ILM peeling could eliminate not only the physical traction of a thickened structure, but also the natural reservoir of AGEs, ROS, and inflammatory molecules. PPV with ILM peeling is a surgical option that should be considered when treating patients with chronic DME.