Early vitrectomy for severe proliferative diabetic retinopathy in eyes with useful vision. Results of a randomized trial--Diabetic Retinopathy Vitrectomy Study Report 3. The Diabetic Retinopathy Vitrectomy Study Research Group

Eye care service utilization and associated factors among diabetic patients in Africa: A Systematic Review and Meta-Analysis

Introduction

'Vision 2020, the Right to Sight', jointly coordinated by the World Health Organization's program for the prevention of blindness and deafness and the international agency for the prevention of blindness, was launched in 1999, however, the initiative faces many challenges to hitting its target. One of the challenges for this is, the absence of comprehensive data regarding eye care service utilization among diabetes mellitus patients in Africa. Therefore, this study was aimed at assessing the prevalence of eye care service utilization and associated factors among adult diabetes mellitus patients in Africa.

Methods

This systematic review and meta-analysis was conducted as per the international preferred reporting items for systematic review and meta-analysis protocols (PRISMA) guidelines. Published articles were searched using reputable databases (PubMed, Cochrane Library) and Web searches (Science Direct, African Journals Online, and Google Scholar). Quality appraisal was assessed based on the Joanna Briggs Institute's (JBI) critical appraisal checklist. The extracted data was exported to STATA version 11 (STATA Corp., LLC) for further analysis. Heterogeneity between the results of primary studies was assessed using Cochran's Q chi-square test and quantified with the I2 statistics. Publication bias was assessed by visual inspection of the funnel plot and Egger's regression tests.

Results

The database search found 26,966 articles. The pooled prevalence of eye care service utilization among diabetic patients in Africa is found to be 40.92 % (95 % CI: 27.14-54.70, P < 0.001). Good knowledge (POR = 3.57, 95 % CI: 2.67-4.76), good attitude (POR = 5.68, 95 % CI: 4.20-7.68), age greater than 65 years old (POR = 7.11, 95 % CI: 3.86-13.10), urban residence (POR = 5.03, 95 % CI: 2.12-11.96), and disease duration greater than 6 years (POR = 3.81, 95 % CI: 2.25-6.45) were factors associated with eye care service utilization.

Conclusion

This meta-analysis revealed that a high proportion of people with diabetes failed to use eye care services. Older age, good knowledge, urban residence and longer duration of illness were found to be the contributing factors for the utilization of eye care services in diabetes mellitus patients. Therefore, by considering the negative impact of low eye care service utilization, it is important to improve the habit of regular screening of the eye into routine assessment of diabetes mellitus follow up targeting patients with older age and longer duration of illness to reduce the magnitude of the problem.

COMPARISON OF THE EFFICACY AND SAFETY OF RANIBIZUMAB 0.5 MG VERSUS 1.0 MG WITH PARS PLANA VITRECTOMY FOR THE TREATMENT OF PROLIFERATIVE DIABETIC RETINOPATHY: A Randomized Controlled Trial

PURPOSE

To investigate the effectiveness of two regimens of ranibizumab-assisted pars plana vitrectomy in the treatment of patients with proliferative diabetic retinopathy.

METHODS

This is a prospective, 6-month, randomized controlled trial. Eighty patients with 87 eyes requiring pars plana vitrectomy treatment for proliferative diabetic retinopathy were included and randomly divided into a 1.0-mg injection group and a 0.5-mg injection group. The ranibizumab was delivered intraoperatively, at the close of surgery. The vitreous hemorrhage grade, best-corrected visual acuity, central macular thickness, and safety data were assessed to Month 6.

RESULTS

The 1.0-mg injection group had a milder grade and a lower reoccurrence rate of early postoperatively vitreous hemorrhage than the 0.5-mg injection group (35.0% and 63.4%, respectively, P = 0.0195). The mean best-corrected visual acuity of two groups was significantly improved from baseline to 6 months after surgery, 1.60 ± 0.72 Logarithm of the Minimum Angle of Resolution (LogMAR) (<20/200) to 0.47 ± 0.49 LogMAR (20/59) for the 1.0-mg injection group and 1.51 ± 0.69 LogMAR (<20/200) to 0.50 ± 0.31 LogMAR (20/63) for the 0.5-mg injection group, but there was no significant difference between the two groups ( P = 0.74). There was no significant difference in the mean decrease in central macular thickness and probability of postoperative adverse events between the two groups.

CONCLUSION

Intravitreal injection of 1.0 mg of ranibizumab after pars plana vitrectomy compared with the recommended dose of 0.5 mg significantly reduced the recurrence and severity of early postoperative vitreous hemorrhage in patients with proliferative diabetic retinopathy. It also contributed to the early recovery of visual acuity after surgery and did not increase postoperative adverse events.

The Economic Burden of Diabetic Retinopathy in Jordan: Cost Analysis and Associated Factors

Objective

Diabetic retinopathy (DR) is the leading cause of visual loss worldwide in patients with diabetes mellitus (DM). The aims of our study are to describe the costs associated with (DR) and to evaluate its economic impact in Jordan.

Methods

Retrospectively, we included all patients with DM and classified them according to the severity of DR. Data regarding medical history, ophthalmic history, stage of DR, presence of DME, and the ophthalmic procedures and operations were collected. The total DR-related cost was measured as a direct medical cost for the outpatient and inpatient services.

Results

Two hundred and twenty-nine patients were included in the study. Only 49.7% of the patients presented without DR, and 21% presented with diabetic macular edema (DME) unilaterally or bilaterally. The DR-related cost was significantly associated with insulin-based regimens, longer duration of DM, higher HbA1c levels, worse stage of DR at presentation, the presence of DME at presentation, the presence of glaucoma, and increased mean number of intravitreal injections, laser sessions, and surgical operations. Multivariate analysis should the presenting stage of DR, presence of DME, and the presence of DME be the independent factors affecting the DR-related cost.

Conclusion

This study is the first study to be conducted in Jordan and encourages us to establish a screening program for DR for earlier detection and treatment. DM control and treatment compliance will reduce the heavy costs of the already exhausted healthcare and financial system.

Silicone Oil Utilized in Pars Plana Vitrectomy for Patients with Advanced Proliferative Diabetic Retinopathy: Physico-Chemical and Optical Properties

OBJECTIVE

Silicone oils have the role in maintaining the attachment of the retina in conditions where the risk of retinal re-detachment is high. However, silicone oils have the tendency to emulsify with subsequent complications. In this work, analyses have been performed to understand changes that occurred to the optical, and physical characteristics of the oil after removal from the vitreous cavity of patients underwent pars plana vitrectomy (PPV) for fibrovascular membranes/tractional retinal detachment (FVM/TRD).

METHODS

Four samples of silicone oil were allocated from patients who underwent PPV for FVM/TRD. The Fourier-transform infrared (FTIR) spectroscopy, micro-viscometry, and ultraviolet-visible spectrometer analyses were utilized to determine the changes in its chemical bondings, viscosity, absorbance, transmittance, buoyance, and specific gravity.

RESULTS

The mean age of the patients was 49.0 years. The mean duration of silicone oil implantation was 18.9 months. FTIR analysis showed significant breaking in the chemical bonding that was related to the lens status during the primary PPV, the presence of significant retinal hemorrhages, the duration of silicone oil implantation, and the degree of silicone oil filling. Similarly, viscosity and contact angle analyses revealed a reduction in the viscosity with similar factors to the FTIR analysis. Moreover, absorbance and transmittance were largely affected by the aggressiveness of FVM/TRD.

CONCLUSION

This study revealed that certain factors such as the age of the patient, duration of silicone oil implantation, lens status, and the presence of retinal hemorrhages, the degree of silicone oil filling and aggressiveness of FVM/TRD may contribute to the emulsification process.

Early versus Late Pars Plana Vitrectomy in Vitreous Hemorrhage: A Systematic Review

Background: Vitreous hemorrhage (VH) is a common vitreoretinal condition causing impairment of vision due to various etiologies. No consensus exists on the best timing for performing pars plana vitrectomy (PPV) in fundus-obscuring VH. Materials and Methods: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards, we conducted a systematic review of the timing of PPV in VH. We assessed the strength of the evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach for all the included publications, in accordance with the 2011 Oxford Centre for Evidence-Based Medicine (OCEBM) recommendations. Results: A total of 1731 articles were identified. Following the removal of duplicates and screening of abstracts, 1203 articles remained. Subsequently, a comprehensive full-text review of 30 articles was conducted. Ultimately, 18 articles met the predefined inclusion criteria. Conclusions: Despite the small number of studies on the timing of treatment for VH, the advantage of early over late PPV seems to be a reasonable approach in selected cases, and it might be considered modern standard care.

[Medico-surgical management of intravitreal hemorrhage in diabetic patients]

Vitreous hemorrhage (VH) is the main complication of proliferative diabetic retinopathy and remains the primary indication for vitrectomy in diabetic patients. The objective of our study is to compare our medical and surgical management of VH with data from the literature and to report the functional results of our series. We studied a series of 284 cases collected over 2 years in two tertiary care centers. In our series, 90.1% of patients had type 2 diabetes, and 70% had glycosylated hemoglobin greater than 7.5%. On fundus examination, 35.2% presented with stage 1 VH, 42.6% with stage 2, 3.6% with stage 3 and 5.2% with stage 4. Ocular ultrasound performed when fundus exam was difficult diagnosed an associated tractional retinal detachment in 8.8% of patients. Medical treatment was sufficient in 77.8% of patients, while 22.2% of our patients underwent vitrectomy, argon laser endophotocoagulation and postoperative anti-VEGF injection. Peeling of tractional fibrovascular membranes and or associated epiretinal membranes was performed in 69.8% of cases. Iatrogenic tears were noted in 11.8% of patients. In this study, 31.5% of patients underwent intraocular gas tamponade, while 23.8% of cases underwent silicone oil tamponade. Postoperative visual acuity improved by at least 2 lines in 60% of our patients, and the VH recurred in 24.2% of cases after surgery.

Safety and effectiveness of pre-emptive diabetic vitrectomy in patients with severe, non-fibrotic retinal neovascularisation despite panretinal photocoagulation

OBJECTIVES

To investigate the safety and effectiveness of pre-emptive vitrectomy in eyes with severe non-fibrotic proliferative diabetic retinopathy.

METHODS

A multi-centre, retrospective, observational study. Pre-emptive vitrectomy was performed in non-fibrotic diabetic eyes with a visual acuity (VA) of 20/50 or better, where there was extensive persistent neovascularisation despite prior panretinal photocoagulation, and where the fellow eye had established sight loss despite vitrectomy for tractional complications. The primary outcome measure was the VA at last visit.

RESULTS

Twenty patients were included. The mean age was 39 ± 14 years. Fifteen patients were Type 1 diabetic. The median baseline VA was 20/30 and remained stable at 20/28 at last visit (median follow-up period: 24 months). Eight eyes (40.0%) developed post-operative vitreous cavity haemorrhage; 4 of which required a vitreous cavity washout procedure. There were no post-operative retinal detachments. The index eye remained the significantly better eye at all time points bar one month post-surgery. Regression of retinopathy grading was observed in all eyes.

CONCLUSION

In this pilot study, we found no sight loss with pre-emptive diabetic vitrectomy. Better eye status was maintained in this high-risk group. Further study with larger number of patients and longer-term follow-up is indicated.

Update on the Management of Diabetic Retinopathy: Anti-VEGF Agents for the Prevention of Complications and Progression of Nonproliferative and Proliferative Retinopathy

Diabetic retinopathy (DR) is a microvascular disease caused by poorly controlled blood glucose, and it is a leading cause of vision loss in people with diabetes. In this review we discuss the current management of DR with particular focus on the use of intraocular anti-vascular endothelial growth factor (anti-VEGF) agents. Intraocular anti-VEGF agents were first studied in the 1990s, and now several of these agents are either FDA approved or used off-label as first-line treatments for DR. Recent evidence shows that anti-VEGF agents can halt the progression of markers of DR severity, reduce the risk of DR worsening, and reduce the onset of new macular edema. These significant benefits have been demonstrated in patients with proliferative DR and the milder nonproliferative DR (NPDR). A wealth of evidence from recent trials and meta-analyses has detailed the intraoperative and postoperative benefits of adjunctive anti-VEGF therapy prior to pars plana vitrectomy (PPV) for proliferative DR with vitreous hemorrhage. In this review, we also discuss literature comparing various anti-VEGF injection regimens including monthly, quarterly, as-needed, and treat and extend protocols. Combination protocols with panretinal photocoagulation (PRP) or PPV are also discussed. Current evidence suggests that anti-VEGF therapies are effective therapy for NPDR and PDR and may also provide significant benefits when used adjunctively with other DR treatment modalities such as PRP or PPV.

Outcomes of Pars Plana Vitrectomy with Panretinal Photocoagulation for Treatment of Proliferative Diabetic Retinopathy Without Retinal Detachment: A Seven-Year Retrospective Study

Objective

To review clinical outcomes of patients with proliferative diabetic retinopathy (PDR) and vitreous hemorrhage (VH) who underwent pars plana vitrectomy (PPV) with endolaser panretinal photocoagulation (PRP) without retinal detachment (RD) repair.

Methods

Retrospective chart review of the rate of postoperative clinical findings and visual acuity in patients with PDR from May 2014 to August 2021.

Results

Pars plana vitrectomy with endolaser PRP was performed in 81 eyes of 81 patients (mean age of 62.1 ± 10.5 years). At a median follow-up of 18 months, mean Snellen best-corrected visual acuity (BCVA) significantly improved from 20/774 preoperatively to 20/53 at last follow-up (P < 0.001). Postoperative complications and clinical findings included VH (12.3%), diabetic macular edema (DME) (12.3%), ocular hypertension (8.6%), RD (4.9%), and need for additional PPV (6.2%). Eyes with PRP performed within 6 months before surgery had a lower frequency of developing postoperative VH (5.3%) compared to eyes that received PRP more than 6 months before surgery (27.3%, P = 0.04). Eyes that received preoperative anti-vascular endothelial growth factor (VEGF) treatment (2.0%) had a lower frequency of postoperative VH compared to eyes that did not receive anti-VEGF treatment (14.3%, P = 0.04). Eyes that received intraoperative sub-tenon triamcinolone acetonide developed postoperative DME (4.0%) less frequently than eyes that did not receive sub-tenon triamcinolone acetonide (26.7%, P = 0.04).

Conclusion

In patients with PDR and VH, PPV with PRP yielded significant improvements in visual acuity and resulted in overall low rates of recurrent postoperative VH. Preoperative anti-VEGF and PRP laser treatment were associated with lower rates of postoperative VH. Furthermore, intraoperative use of sub-tenon triamcinolone acetonide was associated with a lower rate of postoperative DME. Pars plana vitrectomy with endolaser PRP in conjunction with the aforementioned pre- and intraoperative therapies is an effective treatment for patients with PDR and VH.

Long-Term Outcomes of Same Patient Eyes Treated with Pars Plana Vitrectomy in One Eye and Conventional Treatment in the Other for Complications of Proliferative Diabetic Retinopathy

The purpose of this study was to evaluate the long-term, real-world outcomes of pars plana vitrectomy (PPV) for complications of proliferative diabetic retinopathy. A retrospective review involving 64 patients with proliferative diabetic retinopathy that underwent PPV in their worse-seeing eye were followed for a minimum of 8 years. The fellow eye underwent conventional treatment. Patients were divided into two groups by age: patients younger than 50 years of age and patients older than 50. In the younger than 50 group, 89% of vitrectomized eyes had improved visual acuity (VA) while 3.6% had decreased VA. A total of 14% of vitrectomized eyes required additional laser and 11% required reoperations. In the conventional treatment eyes, 25% had improved VA while 68% had decreased VA (p < 0.05). A total of 72% required additional laser and 60% required PPV. In the older than 50 group, 86% of vitrectomized eyes had VA improvement and 3% had decreased VA. A total of 8% required laser and 8% required reoperations. In the conventional treatment eyes, 30% improved VA and 48% had decreased VA (p < 0.05). Additional procedures required included laser in 70% and PPV in 17%. In both age groups, eyes that underwent PPV had better final visual outcomes than eyes that received conventional treatment for PDR.

Non-vasogenic cystoid maculopathies

Besides cystoid macular edema due to a blood-retinal barrier breakdown, another type of macular cystoid spaces referred to as non-vasogenic cystoid maculopathies (NVCM) may be detected on optical coherence tomography but not on fluorescein angiography. Various causes may disrupt retinal cell cohesion or impair retinal pigment epithelium (RPE) and Müller cell functions in the maintenance of retinal dehydration, resulting in cystoid spaces formation. Tractional causes include vitreomacular traction, epiretinal membranes and myopic foveoschisis. Surgical treatment does not always allow cystoid space resorption. In inherited retinal dystrophies, cystoid spaces may be part of the disease as in X-linked retinoschisis or enhanced S-cone syndrome, or occur occasionally as in bestrophinopathies, retinitis pigmentosa and allied diseases, congenital microphthalmia, choroideremia, gyrate atrophy and Bietti crystalline dystrophy. In macular telangiectasia type 2, cystoid spaces and cavitations do not depend on the fluid leakage from telangiectasia. Various causes affecting RPE function may result in NVCM such as chronic central serous chorioretinopathy and paraneoplastic syndromes. Non-exudative age macular degeneration may also be complicated by intraretinal cystoid spaces in the absence of fluorescein leakage. In these diseases, cystoid spaces occur in a context of retinal cell loss. Various causes of optic atrophy, including open-angle glaucoma, result in microcystoid spaces in the inner nuclear layer due to a retrograde transsynaptic degeneration. Lastly, drug toxicity may also induce cystoid maculopathy. Identifying NVCM on multimodal imaging, including fluorescein angiography if needed, allows guiding the diagnosis of the causative disease and choosing adequate treatment when available.

Increasing metabolic variability increases the risk for vitrectomy in proliferative diabetic retinopathy

PURPOSE

Proliferative diabetic retinopathy (PDR) can be treated by retinal photocoagulation, but in some cases, the treatment is initiated too late or is insufficient so that the disease advances to a stage requiring vitrectomy. There is a need to identify risk factors that can predict if patients with PDR will develop complications in need for vitrectomy.

METHODS

Survival analysis with death as competing risk was used to study systemic risk factors for PDR progression to a complication in need for vitrectomy in right eyes of all 1288 diabetic patients from the Aarhus area, Denmark, who had developed proliferative retinopathy in the right eye during the 25 years period from 1 July 1994 until 1 July 2019.

RESULTS

The overall cumulative incidence of reaching a vitrectomy end point in the right eye was 24.1% (n = 311). In 9.3% (n = 120) of the patients where vitrectomy had been performed together with the first photocoagulation, the age of onset of diabetes was significantly higher (p < 0.0001), the diabetes duration longer (p < 0.035) and BMI higher (p < 0.01) than in the patients who had been vitrectomized later than the first photocoagulation. The risk for vitrectomy was significantly increased by high variability of HbA1c before the development of PDR (p < 0.0001), but not by other parameters known to increase the risk for developing PDR.

CONCLUSION

Increasing variability of HbA1c before the development of PDR increases the risk for progression to a complication in need of vitrectomy. The need for vitrectomy is unaffected by other risk factors known to increase the risk for developing PDR.

The Influence of COVID-19 Lockdown in Jordan on Patients with Diabetic Retinopathy: A Case-Control Study

Background

Diabetic retinopathy (DR) is a leading cause of vision impairment in working-age adults. Patients with DR need extensive follow-ups with timely proper treatment. In Jordan, a complete lockdown was decided during the COVID-19 pandemic including the closure of outpatients' clinic. In this study, we assess the effect of the lockdown on the progression and visual outcome for patients with DR who had interruption in their plan.

Methods

Retrospectively, we identified all patients who were scheduled for procedures for the management of diabetic retinopathy (DR) during the COVID-19-related quarantine period in Jordan from March 16th to June 6th, 2020. All demographics and clinical data, procedure information, and visual outcome were collected. Another control group of patients with similar characteristics who were scheduled for procedures related to DR before the COVID-19 pandemic from October 15th to December 31st, 2019 were included.

Results

One hundred and thirty-seven eyes planned for procedures from 89 patients were included. The case group comprises 56 eyes (40.9%). The mean age of the patients was 61.4 years. The right eye was involved in 69 procedures (50.4%). The mean change in visual acuity for the case group in the procedure eye was 0.176 in LogMAR (drop of almost 9 LogMAR letters) and the mean change in visual acuity for the control group in the procedure eye was -0.103 LogMAR (gain of about 5 LogMAR letters). Also, the central subfield thickness (CST) values were significantly worse in the case group. Furthermore, patients in the case group had significantly more disease progression (new findings and worsening of the already established findings).

Conclusion

Interrupting the important procedures for DR patients and delaying their follow-up may adversely affect their visual outcome. National decisions should consider conducting these procedures and exempt those patients from any lockdown with proper precautions. Moreover, certain measures would be considered, such as treat-and-extend protocol, home screening and portable OCT examination, and newer long-acting anti-VEGF drugs.

Recent trends in drug-delivery systems for the treatment of diabetic retinopathy and associated fibrosis

Diabetic retinopathy is a frequent microvascular complication of diabetes and a major cause of visual impairment. In advanced stages, the abnormal neovascularization can lead to fibrosis and subsequent tractional retinal detachment and blindness. The low bioavailability of the drugs at the target site imposed by the anatomic and physiologic barriers within the eye, requires long term treatments with frequent injections that often compromise patient's compliance and increase the risk of developing more complications. In recent years, much effort has been put towards the development of new drug delivery platforms aiming to enhance their permeation, to prolong their retention time at the target site and to provide a sustained release with reduced toxicity and improved efficacy. This review provides an overview of the etiology and pathophysiology of diabetic retinopathy and current treatments. It addresses the specific challenges associated to the different ocular delivery routes and provides a critical review of the most recent developments made in the drug delivery field.

Causes and Clinical Impact of Loss to Follow-Up in Patients with Proliferative Diabetic Retinopathy

Purpose

This study determined the clinical impact and causes of loss to follow-up (LTFU) from the patients' perspective in individuals with proliferative diabetic retinopathy (PDR) who received panretinal photocoagulation (PRP) and/or intravitreal injections (IVIs) of antivascular endothelial growth factor (VEGF).

Methods

This prospective cohort study included 467 patients with PDR who received PRP and/or IVIs of anti-VEGF between May 2013 and June 2018. LTFU was defined as missing any follow-up visit for any interval exceeding 6 months, provided that patients eventually resumed care. Main outcome measures include rates and causes of LTFU.

Results

A total of 391 patients (83.7%) were followed up, and 76 patients (16.3%) were LTFU over the study period. Rates of LTFU decreased with age (P=0.005). Questionnaire analysis conducted for patients' LTFU showed a significant positive correlation between best corrected visual activity (BCVA) loss and patient's lack of trust and satisfaction with treatment (rs = 0.458, P=0.005). Questionnaire analysis conducted for patients' LTFU showed a significant positive correlation between best corrected visual activity (BCVA) loss and patient's lack of trust and satisfaction with treatment (rs = 0.458, P=0.005). Questionnaire analysis conducted for patients' LTFU showed a significant positive correlation between best corrected visual activity (BCVA) loss and patient's lack of trust and satisfaction with treatment (rs = 0.458, P=0.005). Questionnaire analysis conducted for patients' LTFU showed a significant positive correlation between best corrected visual activity (BCVA) loss and patient's lack of trust and satisfaction with treatment (rs = 0.458,

Conclusions

LTFU threatens vision in PDR patients receiving PRP and/or IVIs of anti-VEGF. Possibly, patient-specific LTFU causes should be addressed before treatment in order to minimize the risk of LTFU. The clinical trial is registered with NCT04018326 (trial registration: ClinicalTrials.gov Identifier: NCT04018326, 10th of July 2019 “Retrospectively registered”).

Surgical outcomes of vitrectomy surgery for proliferative diabetic retinopathy in patients with abnormal renal function

PURPOSE

To analyse the influence of renal function on the outcomes of vitrectomy for tractional-related complications in cases of severe proliferative diabetic retinopathy (PDR).

METHODS

Retrospective consecutive case series of 109 eyes that underwent vitreoretinal interventions for traction-related complications of severe PDR from 2014 to 2017. Data collected included patient demographics, best-corrected visual acuity (BCVA), surgical complications, and systemic markers including HbA1c and estimated glomerular filtration rate (eGFR). Renal function categories were defined as low (eGFR < 30 mL/min/1.73 m²), medium (eGFR 30-60 mL/min/1.73 m²), and normal (eGFR > 60 mL/min/1.73m ²).

RESULTS

A total of 109 eyes (56% (n = 61) female) were included in the study. Overall, mean baseline BCVA improved from 1.33 logMAR to 0.91 logMAR (p < 0.001) postoperatively. Patients with low eGFR had significantly worse baseline BCVA (p = 0.039) and demonstrated greater improvement in mean BCVA (p = 0.059). Multivariate regression analysis indicated that seven predictors explained 65.5% of the variance (R² = 0.655, F(11,97) = 16.7, p < 0.01).

CONCLUSIONS

Reduced renal function does not adversely affect visual outcomes of vitrectomy for traction-related complications of PDR.

The estimated healthcare cost of diabetic retinopathy in Indonesia and its projection for 2025

PURPOSE

To estimate the total healthcare cost associated with diabetic retinopathy (DR) in type 2 diabetes in Indonesia and its projection for 2025.

METHODS

A prevalence-based cost-of-illness model was constructed from previous population-based DR study. Projection for 2025 was derived from estimated diabetes population in 2025. Direct treatment costs of DR were estimated from the perspective of healthcare. Patient perspective costs were obtained from thorough interview including only transportation cost and lost of working days related to treatment. We developed four cost-of-illness models according to DR severity level, DR without necessary treatment, needing laser treatment, laser +intravitreal (IVT) injection and laser + IVT +vitrectomy. All costs were estimated in 2017 US$.

RESULTS

The healthcare costs of DR in Indonesia were estimated to be $2.4 billion in 2017 and $8.9 billion in 2025. The total cost in 2017 consisted of the cost for no DR and mild-moderate non-proliferative DR (NPDR) requiring eye screening ($25.9 million), severe NPDR or proliferative DR (PDR) requiring laser treatment ($0.25 billion), severe NPDR or PDR requiring both laser and IVT injection ($1.75 billion) and advance level of PDR requiring vitrectomy ($0.44 billion).

CONCLUSIONS

The estimated healthcare cost of DR in Indonesia in 2017 was considerably high, nearly 2% of the 2017 national state budget, and projected to increase significantly to more than threefold in 2025. The highest cost may incur for DR requiring both laser and IVT injection. Therefore, public health intervention to delay or prevent severe DR may substantially reduce the healthcare cost of DR in Indonesia.

A qualitative study on barriers and enablers to uptake of diabetic retinopathy screening by people with diabetes in the Western Province of Sri Lanka

Background

Blindness and visual impairment from diabetic retinopathy (DR) are avoidable through early detection and timely treatment. The Western Province of Sri Lanka has the highest prevalence of diabetes mellitus (DM) (18.6%) in the country. A situational analysis identified a significant gap in DR screening services (DRSS) uptake in this region. Barriers that hinder people with DM (PwDM) from attending DRSS are poorly understood. The purpose of this study is to understand the factors which influence the uptake of DRSS and follow-up to inform health promotion strategies and improve the uptake of these services.

Methods

Eleven focus group discussions (FGDs) were conducted with PwDM who presented to medical, general eye and vitreoretinal services in three public sector institutions (two tertiary and one secondary level) in the Western Province between October 2016 and March 2017. We enrolled six groups (four Sinhala speaking, two Tamil) of women and five groups (three Sinhala and two Tamil) of men representing ethnicity and gender. We performed a thematic analysis and described the main themes and subthemes using the socio-ecological model as a framework.

Results

We identified lack of knowledge of both the condition and the need for screening as key barriers to access DRSS. Socio-cultural factors in the family environment, economic reasons and institutional factors were also important barriers. Additional reasons include long waiting time at eye clinics and poor referrals exacerbated by the lack of a systematic DRSS. In addition, attitudes to DRSS such as fear of discomfort from the procedure and the need for accompaniment following mydriasis were also deterrents to follow-up screening.

Conclusion

This study has shown that there are inter-related user, family, and institutional factors which affect the uptake of DRSS. Understanding how DR is conceptualised by PwDM in this region is essential to refine strategies to improve access to DRSS. Strategies to improve knowledge need to be more culturally acceptable and relevant to PwDM and their families, with increased availability of DRSS at convenient locations may increase timely uptake of screening.

Electronic supplementary material

The online version of this article (10.1186/s41182-019-0160-y) contains supplementary material, which is available to authorized users.

Surgical management of diabetic tractional retinal detachments

Tractional retinal detachment is an end-stage form of diabetic retinopathy that occurs when contractile forces in the vitreous and neovascular tissue lead to the detachment of the neurosensory retina. We review the literature related to the management of this disease. Preoperative planning includes appropriate patient selection, diagnostic and prognostic imaging, and medical optimization with reduction of systemic risk factors. Use of antivascular endothelial growth factor for preoperative treatment has had significant benefits for tractional retinal detachment repair in improving surgical efficiency and outcomes. Advances in microsurgical instrumentation are discussed, with attention to small-gauge vitrectomy with improved flow dynamics, viewing strategies, and lighting allowing bimanual surgery. Special emphasis is placed on bimanual surgical technique, choice of tamponade, and the avoidance of iatrogenic damage. Complications and special considerations are further explored. Based on our compilation of relevant literature, we propose a surgical algorithm for the management of these complex patients.

Systematic review on barriers and enablers for access to diabetic retinopathy screening services in different income settings

BACKGROUND

Diabetic retinopathy (DR) can lead to visual impairment and blindness if not detected and treated in time. Knowing the barriers/enablers in advance in contrasting different country income settings may accelerate development of a successful DR screening (DRS) program. This would be especially applicable in the low-income settings with the rising prevalence of DR.

OBJECTIVES

The aim of this systematic review is to identify and contrast the barriers/enablers to DRS for different contexts using both consumers i.e., people with diabetes (PwDM) and provider perspectives and system level factors in different country income settings.

METHODS

We searched MEDLINE, Embase, CENTRAL in the Cochrane Library from the databases start date to December 2018. We included the studies reported on barriers and enablers to access DRS services based at health care facilities. We categorised and synthesized themes related to the consumers (individuals), providers and the health systems (environment) as main dimensions according to the constructs of social cognitive theory, supported by the quantitative measures i.e., odds ratios as reported by each of the study authors.

MAIN RESULTS

We included 77 studies primarily describing the barriers and enablers. Most of the studies were from high income settings (72.7%, 56/77) and cross sectional in design (76.6%, 59/77). From the perspectives of consumers, lack of knowledge, attitude, awareness and motivation were identified as major barriers. The enablers were fear of blindness, proximity of screening facility, experiences of vision loss and being concerned of eye complications. In providers' perspectives, lack of skilled human resources, training programs, infrastructure of retinal imaging and cost of services were the main barriers. Higher odds of uptake of DRS services was observed when PwDM were provided health education (odds ratio (OR) 4.3) and having knowledge on DR (OR range 1.3-19.7).

CONCLUSION

Knowing the barriers to access DRS is a pre-requisite in development of a successful screening program. The awareness, knowledge and attitude of the consumers, availability of skilled human resources and infrastructure emerged as the major barriers to access to DRS in any income setting.

The Oxidative Stress and Mitochondrial Dysfunction during the Pathogenesis of Diabetic Retinopathy

Diabetic retinopathy is one of the most serious microvascular complications induced by hyperglycemia via five major pathways, including polyol, hexosamine, protein kinase C, and angiotensin II pathways and the accumulation of advanced glycation end products. The hyperglycemia-induced overproduction of reactive oxygen species (ROS) induces local inflammation, mitochondrial dysfunction, microvascular dysfunction, and cell apoptosis. The accumulation of ROS, local inflammation, and cell death are tightly linked and considerably affect all phases of diabetic retinopathy pathogenesis. Furthermore, microvascular dysfunction induces ischemia and local inflammation, leading to neovascularization, macular edema, and neurodysfunction, ultimately leading to long-term blindness. Therefore, it is crucial to understand and elucidate the detailed mechanisms underlying the development of diabetic retinopathy. In this review, we summarized the existing knowledge about the pathogenesis and current strategies for the treatment of diabetic retinopathy, and we believe this systematization will help and support further research in this area.

Cost Evaluation of Early Vitrectomy versus Panretinal Photocoagulation and Intravitreal Ranibizumab for Proliferative Diabetic Retinopathy

PURPOSE

To evaluate costs and cost-utility of early vitrectomy (pars plana vitrectomy [PPV]) compared with panretinal photocoagulation (PRP) and intravitreal ranibizumab (IVR) for proliferative diabetic retinopathy (PDR) without diabetic macular edema.

DESIGN

A decision analysis model of cost-utility.

PARTICIPANTS

There were no participants.

METHODS

A decision analysis was based on results from the Diabetic Retinopathy Clinical Research Network Protocol S comparing treatment of PRP with IVR (0.3 mg) in PDR without incident macular edema to model the total 2-year costs and outcomes for each treatment scenario. These values were compared with the 2-year hypothetical costs of early PPV for PDR. Centers for Medicare and Medicaid Services data were used to calculate associated modeled costs in a hospital/facility-based and nonfacility setting. Cost-utility was calculated on the basis of the preserved visual utility and estimated life years remaining. In addition, costs for lifetime treatment were modeled for all scenarios and used to calculate lifetime quality-adjusted life years (QALY) costs for each scenario. Sensitivity analyses were performed to evaluate the impact of the model's assumptions.

MAIN OUTCOME MEASURES

Cost of treatment, utility, and cost per QALY.

RESULTS

The modeled cost per QALY of treatment for PDR for 2 years of utility in the facility (nonfacility) setting was $163 988 ($102 559) in the PRP group, $436 992 ($326 424) in the IVR group, and $181 144 ($107 965) in the PPV group. Sensitivity analysis showed that both IVR and PPV groups would have equivalent costs per QALY over the first 2 years if 78% (facility) and 80% (nonfacility) of patients in the PPV group required additional treatment with IVR (at the dose of 10.1 injections as in Protocol S). Beyond 2 years, the cost per QALY in the facility (nonfacility) setting was calculated as $61 695 ($21 752) in the PRP group, $338 348 ($239 741) in the IVR group, and $63 942 ($22 261) in the PPV group.

CONCLUSIONS

Early PPV as a strategy for treatment of PDR without macular edema demonstrates cost-utility similar to management with PRP and more favorable cost-utility compared with IVR in the short term. This advantage over IVR continues when lifetime costs are factored.

Experience with Intravitreal Bevacizumab as a Preoperative Adjunct in 23-G Vitrectomy for Advanced Proliferative Diabetic Retinopathy

Purpose

To evaluate the safety and efficacy of intravitreal injection of bevacizumab before vitrectomy in advanced proliferative diabetic retinopathy.

Methods

A randomized clinical trial was performed on 40 eyes of 40 patients. Inclusion criteria were advanced proliferative diabetic retinopathy with fractional retinal detachment and HbA1c <7%. Patients were randomly assigned into 2 groups. Patients in one group had an intravitreal injection (1.25 mg) of bevacizumab 48 hours before 23-G pars plana vitrectomy surgery was performed, whereas the other group did not. Best-corrected visual acuity, intraocular pressure, and fundus photographs were taken prior to surgery 1 week and 3 and 6 months postoperatively.

Results

Effective vitrectomy time was 8.05 minutes in the bevacizumab group vs 16.8 minutes in the non-bevacizumab group. Statistically significant differences were observed in visual acuity at 1 week and 3 and 6 months follow-up between the 2 groups (p<0.05 for each visit). Also, there was less bleeding intraoperatively in the bevacizumab group. Mean final visual acuity in the bevacizumab group was 0.82 logMAR and 2.01 logMAR in the non-bevacizumab group.

Conclusions

Adjuvant intravitreal injection of bevacizumab prior to vitrectomy in diabetic retinopathy with fractional retinal detachment significantly eases the procedure, diminishing intraoperative complications, and leads to a better visual outcome.

Bimanual Technique in Proliferative Diabetic Retinopathy Using an Optical Fiber-Free Intravitreal Surgery System: A Case Control Study

Purpose

To evaluate the results of bimanual membrane peeling technique with an optical fiber-free intravitreal surgery system (OFFISS) in eyes with fibrovascular proliferation due to diabetic retinopathy.

Methods

Fifteen eyes of 14 consecutive patients with severe fibrovascular proliferation due to diabetic retinopathy who underwent bimanual vitrectomy using the OFFISS and 15 eyes of 15 nonconsecutive patients with similar fundus condition who underwent vitrectomy using a conventional microscope system were compared in a retrospective, consecutive case-control series.

Results

Reattachment rates at 3 months following surgery for the cases and controls were 93% and 100%, respectively, and final reattachment rates for both were 100%. The best-corrected visual acuity improved by two lines or more in 100% of the cases as compared to 87% of the controls (p=0.48). The mean VA (logMAR) improved 1.08 in the cases and 0.93 in the controls at final examination (p=0.46). Surgical complications were rare in both groups (p>0.05). The mean duration of membrane peeling of the cases was significantly lower than the controls (p=0.01).

Conclusions

For complicated surgical manipulations such as membrane peeling in diabetic vitrectomy for severe fibrovascular proliferation, bimanual vitrectomy using the OFFISS is a more effective and safer alternative to the conventional vitrectomy method.

Surgery for postvitrectomy cataract

BACKGROUND

Cataract formation or acceleration can occur after intraocular surgery, especially following vitrectomy, a surgical technique for removing the vitreous that is used in the treatment of many disorders that affect the posterior segment of the eye. The underlying problem that led to vitrectomy may limit the benefit from removal of the cataractous lens.

OBJECTIVES

To evaluate the effectiveness and safety of surgery versus no surgery for postvitrectomy cataract with respect to visual acuity, quality of life, and other outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2017, Issue 5), MEDLINE Ovid (1946 to 17 May 2017), Embase.com (1947 to 17 May 2017), PubMed (1946 to 17 May 2017), Latin American and Caribbean Health Sciences Literature database (LILACS) (January 1982 to 17 May 2017), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com); last searched May 2013, ClinicalTrials.gov (www.clinicaltrials.gov); searched 17 May 2017, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 17 May 2017. We did not use any date or language restrictions in the electronic searches for trials.

SELECTION CRITERIA

We planned to include randomized controlled trials (RCTs) and quasi-RCTs that had compared surgery versus no surgery to remove the lens from eyes of adults in which cataracts had developed following vitrectomy.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results according to the standard methodological procedures expected by Cochrane.

MAIN RESULTS

We found no RCTs or quasi-RCTs that had compared surgery versus no surgery to remove the lens from eyes of adults in which cataracts had developed following vitrectomy.

AUTHORS' CONCLUSIONS

There is no evidence from RCTs or quasi-RCTs on which to base clinical recommendations for surgery for postvitrectomy cataract. There is a clear need for RCTs to address this evidence gap. Such trials should stratify participants by their age, the retinal disorder leading to vitrectomy, and the status of the underlying disease process in the contralateral eye. Outcomes assessed in such trials may include changes (both gains and losses) of visual acuity, quality of life, and adverse events such as posterior capsular rupture and retinal detachment. Both short-term (six-month) and long-term (one- or two-year) outcomes should be examined.

Postoperative Complications of Pars Plana Vitrectomy for Diabetic Retinal Disease

Despite recent advances in the medical management of diabetic retinal disease, there remain established indications for vitreoretinal surgery in the treatment of severe proliferative diabetic retinopathy. These include non-clearing vitreous hemorrhage and tractional retinal detachment. Advances in surgical instrumentation, technique, and experience have led to improved visual outcomes, as well as a corresponding decrease in the incidence of postoperative complications. However, the presence of systemic and ocular factors in diabetic patients increases the risk of adverse events compared to non-diabetic individuals. This review will focus on the most important postoperative complications following pars plana vitrectomy, with specific considerations for the diabetic patient.

Recent advances in the management and understanding of diabetic retinopathy

Despite recent advances in the diagnosis and treatment of diabetic retinopathy, this complication remains a steadfast challenge to patients and physicians. This review summarizes recent progress in the diagnosis and management of diabetic retinopathy, including automated screening, optical coherence tomography, control of systemic risk factors, surgical techniques, laser treatment, and pharmaceutical treatment, including vascular endothelial growth factor inhibitors. Recent advances in pharmaceutical treatments, in particular, hold strong promise of halting and sometimes reversing the disease process. Clinicians nevertheless must remain vigilant in their efforts to diagnose and treat this disease early in its course.

Surgery for Diabetic Eye Complications

New modalities for the treatment of diabetic eye complications have emerged in the past decade. Nevertheless, many severe diabetic retinopathy complications can only be treated with vitreoretinal surgery. Technological advances in pars plana vitrectomy have expanded the gamut of pathologies that can be successfully treated with surgery. The most common pathologies managed surgically include vitreous opacities and traction retinal detachment. The indications, surgical objectives, adjunctive pharmacotherapy, microincisional surgical techniques, and outcomes of diabetic vitrectomy for proliferative diabetic retinopathy and diabetic tractional retinal detachment will be discussed. With the availability of new microincisional vitrectomy technology, wide angle microscope viewing systems, and pharmacologic agents, vitrectomy can improve visual acuity and achieve long-term anatomic stability in eyes with severe complications from proliferative diabetic retinopathy.

Diabetic Retinopathy Clinical Practice Guidelines: Customized for Iranian Population

PURPOSE

To customize clinical practice guidelines (CPGs) for management of diabetic retinopathy (DR) in the Iranian population.

METHODS

Three DR CPGs (The Royal College of Ophthalmologists 2013, American Academy of Ophthalmology [Preferred Practice Pattern 2012], and Australian Diabetes Society 2008) were selected from the literature using the AGREE tool. Clinical questions were designed and summarized into four tables by the customization team. The components of the clinical questions along with pertinent recommendations extracted from the above-mentioned CPGs; details of the supporting articles and their levels of evidence; clinical recommendations considering clinical benefits, cost and side effects; and revised recommendations based on customization capability (applicability, acceptability, external validity) were recorded in 4 tables, respectively. Customized recommendations were sent to the faculty members of all universities across the country to score the recommendations from 1 to 9.

RESULTS

Agreed recommendations were accepted as the final recommendations while the non-agreed ones were approved after revision. Eventually, 29 customized recommendations under three major categories consisting of screening, diagnosis and treatment of DR were developed along with their sources and levels of evidence.

CONCLUSION

This customized CPGs for management of DR can be used to standardize the referral pathway, diagnosis and treatment of patients with diabetic retinopathy.

The outcomes and prognostic factors of vitrectomy in chronic diabetic traction macular detachment

Purpose

To investigate the outcomes of pars plana vitrectomy (PPV) for chronic diabetic traction macular detachment (CTMD).

Methods

Ninety-six eyes that underwent PPV for CTMD of at least 6 months duration were retrospectively analyzed. Retinal reattachment rate, final vision, and prognostic factors for poor visual outcome were the main outcome measures.

Results

All eyes had long-standing TMD (median 12, range: 6–70 months). The median postoperative follow-up was 15 (range: 3–65) months. Eighty-seven eyes (90.6%) had their retina and macula reattached after one PPV. At final examination, 84 eyes (87.5%) had stable vision or at least one line improvement, and three had no light perception. Seventeen (17.7%) and 41 (43%) eyes had preoperative visual acuity of ≥20/200 and ≥5/200 as compared to 40 (41.6%; P=0.0005) and 64 (66.7%; P=0.0014) eyes at final follow-up, respectively. Age >50 years (Odds ratio [OR] =5.84, 95% confidence interval [CI] =1.53–22.19, P=0.01), preoperative vision <20/400 (OR =7.012, 95% CI =1.82–26.93, P=0.005), and ischemic macula (OR =14.13, 95% CI =3.61–55.33, P<0.001) were significantly associated with final vision <20/400.

Conclusion

PPV for CTMD may be beneficial particularly in patients who are relatively younger and have good baseline vision and no macular ischemia.

A Comparison of Immediate and Delayed Vitrectomy for the Management of Vitreous Hemorrhage due to Proliferative Diabetic Retinopathy

BACKGROUND AND OBJECTIVE

To compare immediate and delayed vitrectomy for the management of vitreous hemorrhage (VH) due to proliferative diabetic retinopathy (PDR).

PATIENTS AND METHODS

Retrospective review of 134 eyes receiving vitrectomy for non-clearing, PDR-associated VH. Primary outcome was area under the vision curve (AUC) in patients receiving immediate (< 30 days) versus delayed (> 30 days) vitrectomy with endolaser.

RESULTS

Forty-six eyes were included, with 17 undergoing immediate (< 30 days) vitrectomy with endolaser and 29 undergoing delayed (> 30 days) vitrectomy with endolaser. Time to vitrectomy was 14.8 days ± 8.26 days compared to 629.6 days ± 894.9 days in the immediate and delayed groups, respectively. AUC was significantly greater for patients undergoing delayed versus immediate vitrectomy (276.1 ± 0.601 logMAR*time versus 165.7 ± 0.761 logMAR*time; P < .0001). There was no difference in AUC postoperatively for delayed versus immediate surgery. Both groups required significantly less postoperative panretinal photocoagulation (P < .05). Preoperative and final visual acuities were equivalent (immediate: 1.86 ± 0.99 and 0.35 ± 0.25; P = .002; delayed: 1.71 ± 1.05 and 0.31 ± 0.34; P < .0001).

CONCLUSIONS

Immediate vitrectomy with endolaser for PDR-associated VH (< 30 days) decreases time spent with vision loss and the need for adjunctive PRP. Modern vitrectomy is safe and may be considered earlier in VH management.

Surgery for Proliferative Diabetic Retinopathy: New Tips and Tricks

Over the recent years, retina specialists have enjoyed significant improvements in the surgical management of proliferative diabetic retinopathy including improved preoperative planning, vitreoretinal instrumentation and new surgical maneuvers. In this review, we present new tips and tricks such as preoperative pharmacotherapy approaches including pegaptanib injection and biodegradable dexamethasone implantation, bimanual vitrectomy techniques and the concept of mixing small gauges as well as valved cannulas and intraoperative optical coherence tomography. With advanced surgical planning and sophisticated operative maneuvers tailored to the individual patient, excellent outcomes can be achieved even in severe cases of diabetic tractional detachment.

Acute-Onset Vitreous Hemorrhage of Unknown Origin before Vitrectomy: Causes and Prognosis

Purpose. To analyze causes and prognosis of acute-onset preoperatively unknown origin vitreous hemorrhage (VH). Methods. This study included patients who underwent vitrectomy for acute-onset preoperatively unknown origin VH. The underlying causes of VH, which were identified after vitrectomy, were analyzed. And overall visual prognosis of unknown origin VH was analyzed. Risk scoring system was developed to predict visual prognosis after vitrectomy. Results. 169 eyes were included. Among these, retinal vein occlusion (RVO), retinal break, and age-related macular degeneration (AMD) were identified in 74 (43.8%), 50 (29.6%), and 21 (12.4%) patients, respectively. After vitrectomy, logMAR BCVA significantly improved from 1.93 ± 0.59 to 0.47 ± 0.71. However, postoperative BCVA in AMD eyes were significantly poorer than others. Poor visual prognosis after vitrectomy was associated with old age, poor preoperative vision in both eyes, and drusen in the fellow eye. Conclusions. RVO, retinal break, and AMD are the most common causes of acute-onset preoperatively unknown origin VH and the most common causes of VH change with age. The visual prognosis of unknown origin VH is relatively good, except among AMD patients. Older patients with poor preoperative BCVA in both eyes and patients with AMD in the fellow eye are at a higher risk of poor visual prognosis following vitrectomy.

Surgical outcomes of florid diabetic retinopathy treated with antivascular endothelial growth factor

PURPOSE

To evaluate the effectiveness of vitreoretinal surgery combined with antivascular endothelial growth factor therapy to treat florid diabetic retinopathy, a rare and severe form of diabetic retinopathy in young patients.

METHODS

Retrospective observational case series including 61 eyes of 45 patients operated on for florid diabetic retinopathy over the past 5 years, with preoperative or intraoperative intravitreal injection of bevacizumab. Cases were classified into three stages of disease severity, according to the extension of the fibrovascular membranes. Main outcome measures were mean change in visual acuity, anatomical outcome, and surgical complications.

RESULTS

After a mean follow-up of 20.3 months, the mean visual acuity significantly increased from +1.7 logMAR before surgery to +0.8 logMAR after surgery (P < 0.01). The visual gain was significant in Stages I and II (P < 0.05) but not significant in Stage III. A flat retina without silicone oil was achieved in 84% of eyes. Eight eyes (13%) progressed to neovascular glaucoma and/or phthisis despite repeated surgeries.

CONCLUSION

Vitrectomy combined with antivascular endothelial growth factor therapy allows both favorable visual and anatomical outcomes in this rapidly evolving disease. Prognosis remains poor in severe stages, suggesting that the earlier the surgery performed, the better is the visual prognosis.

Surgery for post-vitrectomy cataract

BACKGROUND

Cataract formation or acceleration can occur after intraocular surgery, especially following vitrectomy, a surgical technique for removing the vitreous which is used in the treatment of disorders that affect the posterior segment of the eye. The underlying problem that led to vitrectomy may limit the benefit from cataract surgery.

OBJECTIVES

The objective of this review was to evaluate the effectiveness and safety of surgery for post-vitrectomy cataract with respect to visual acuity, quality of life, and other outcomes.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 4), Ovid MEDLINE, Ovid MEDLINE in-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily Update, Ovid OLDMEDLINE (January 1946 to May 2013), EMBASE (January 1980 to May 2013, Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to May 2013), PubMed (January 1946 to May 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 22 May 2013.

SELECTION CRITERIA

We planned to include randomized and quasi-randomized controlled trials comparing cataract surgery with no surgery in adult patients who developed cataract following vitrectomy.

DATA COLLECTION AND ANALYSIS

Two authors screened the search results independently according to the standard methodological procedures expected by The Cochrane Collaboration.

MAIN RESULTS

We found no randomized or quasi-randomized controlled trials comparing cataract surgery with no cataract surgery for patients who developed cataracts following vitrectomy surgery.

AUTHORS' CONCLUSIONS

There is no evidence from randomized or quasi-randomized controlled trials on which to base clinical recommendations for surgery for post-vitrectomy cataract. There is a clear need for randomized controlled trials to address this evidence gap. Such trials should stratify participants by their age, the retinal disorder leading to vitrectomy, and the status of the underlying disease process in the contralateral eye. Outcomes assessed in such trials may include gain of vision on the Early Treatment Diabetic Retinopathy Study (ETDRS) scale, quality of life, and adverse events such as posterior capsular rupture. Both short-term (six-month) and long-term (one-year or two-year) outcomes should be examined.

Anti-vascular endothelial growth factor therapy for diabetic macular edema

Diabetes mellitus is a serious health problem that affects over 350 million individuals worldwide. Diabetic retinopathy (DR), which is the most common microvascular complication of diabetes, is the leading cause of new cases of blindness in working-aged adults. Diabetic macular edema (DME) is an advanced, vision-limiting complication of DR that affects nearly 30% of patients who have had diabetes for at least 20 years and is responsible for much of the vision loss due to DR. The historic standard of care for DME has been macular laser photocoagulation, which has been shown to stabilize vision and reduce the rate of further vision loss by 50%; however, macular laser leads to significant vision recovery in only 15% of treated patients. Mechanisms contributing to the microvascular damage in DR and DME include the direct toxic effects of hyperglycemia, sustained alterations in cell signaling pathways, and chronic microvascular inflammation with leukocyte-mediated injury. Chronic retinal microvascular damage results in elevation of intraocular levels of vascular endothelial growth factor A (VEGF), a potent, diffusible, endothelial-specific mitogen that mediates many important physiologic processes, including but not limited to the development and permeability of the vasculature. The identification of VEGF as an important pathophysiologic mediator of DME suggested that anti-VEGF therapy delivered to the eye might lead to improved visual outcomes in this disease. To date, four different inhibitors of VEGF, each administered by intraocular injection, have been tested in prospective, randomized phase II or phase III clinical trials in patients with DME. The results from these trials demonstrate that treatment with anti-VEGF agents results in substantially improved visual and anatomic outcomes compared with laser photocoagulation, and avoid the ocular side effects associated with laser treatment. Thus, anti-VEGF therapy has become the preferred treatment option for the management of DME in many patients.

Inflammation and pharmacological treatment in diabetic retinopathy

Diabetic retinopathy (DR), the most common microvascular complication of diabetes mellitus, is estimated to be the leading cause of new blindness in the working population of developed countries. Primary interventions such as intensive glycemic control, strict blood pressure regulation, and lipid-modifying therapy as well as local ocular treatment (laser photocoagulation and pars plana vitrectomy) can significantly reduce the risk of retinopathy occurrence and progression. Considering the limitations of current DR treatments development of new therapeutic strategies, it becomes necessary to focus on pharmacological treatment. Currently, there is increasing evidence that inflammatory processes have a considerable role in the pathogenesis of DR with multiple studies showing an association of various systemic as well as local (vitreous and aqueous fluid) inflammatory factors and the progression of DR. Since inflammation is identified as a relevant mechanism, significant effort has been directed to the development of new concepts for the prevention and treatment of DR acting on the inflammatory processes and the use of pharmacological agents with anti-inflammatory effect. Inhibiting the inflammatory pathway could be an appealing treatment option for DR in future practices, and as further prospective randomized clinical trials accumulate data, the role and guidelines of anti-inflammatory pharmacologic treatments will become clearer.

Outcome of a Single Intravitreal Bevacizumab Injection on the Visual Acuity and Course of Pars Plana Vitrectomy in Proliferative Diabetic Retinopathy

Abstract Purpose: To evaluate the effect of a single intravitreal 1.25 mg/0.05 ml bevacizumab (IVB) (Avastin, Genentech) injection on the visual outcome and both intraoperative and postoperative course of pars plana vitrectomy (PPV) in proliferative diabetic retinopathy. Study Design: Prospective case-control interventional comparative study. Methods: One hundred patients (100 eyes) were divided into two groups: Group I had undergone PPV with preoperactive IVB (50 patients), and Group II had undergone PPV without IVB (50 patients). Best corrected visual acuity (BCVA), intraoperative and postoperative complications were compared between both groups. Patients were followed-up for one year. Results: After one year, there was a highly statistically significant difference in the mean BCVA, as it was (0.146 ± 0.103) in Group I and 0.069 ± 0.049 in Group II with (p < 0.001), while mean bleeding frequency in Group I was 0.7 ± 0.78 times/case with range between 0 and 2 bleeding attacks/case and mean bleeding frequency in Group II was 3.12 ± 1.31times/case with range between 3 and 6 bleeding attacks/case and the difference was statistically significant as (p < 0.001). Diathermy was used in Group I in 15 patients only with mean frequency of 0.3 ± 0.46 times/case with range between 0 and 1 attack/case; while diathermy was used in all cases in Group II with mean frequency of 2.4 ± 1.06 times/case with range between 1 to 4 times/case and this difference was also statistically significant as p < 0.001. Postoperative vitreous hemorrhage developed in 3 eyes (6%) in Group I and 15 eyes (30%) in Group II and this difference was statistically significant (p < 0.003). All the other intraoperative and postoperative complications were reduced in Group I, but with no statistically significant difference between both groups. Conclusions: The use of intravitreal bevacizumab before pars plana vitrectomy is beneficial in improving visual outcome, minimizing the incidence of intraoperative bleeding and reducing the need for intraoperative diathermy.