Surgical management of the late complications of proliferative diabetic retinopathy

Comparison of the Risk of Diabetic Retinopathy Between Sodium-Glucose Cotransporter-2 Inhibitors and Dipeptidyl Peptidase-4 Inhibitors in Patients with Type 2 Diabetes Mellitus in Japan: A Retrospective Analysis of Real-World Data

INTRODUCTION

Diabetic retinopathy (DR), a microvascular complication of type 2 diabetes mellitus (T2DM), is a leading cause of blindness and has detrimental effects on patients' quality of life. We compared the risk of DR diagnosis with sodium-glucose cotransporter-2 inhibitors (SGLT2i) versus dipeptidyl peptidase-4 inhibitors (DPP-4i) in patients with T2DM in Japan.

METHODS

This Japanese retrospective cohort study used the JMDC Claims Database (data collected from January 2015 to September 2022). Patients with T2DM and no record of microvascular or macrovascular diseases who were newly treated with an SGLT2i (23,061 patients) or a DPP-4i (53,986 patients) were matched 1:1 using propensity score (10,166 per matched group). Incidence rates (IRs) and cumulative IRs of DR diagnosis were calculated for each treatment group; hazard ratio (HR) and its 95% confidence interval (CI) were calculated using Cox proportional hazard models to compare the risk between the groups.

RESULTS

The IR of DR diagnosis was 46.23 and 57.12 per 1000 person-years in the SGLT2i and DPP-4i groups, respectively, with a significantly lower risk in the SGLT2i group than in the DPP-4i group (HR 0.83, 95% CI 0.75-0.92, P = 0.0003).

CONCLUSIONS

In this study, the risk of DR diagnosis was lower with SGLT2i compared with DPP-4i in patients with T2DM without microvascular and macrovascular diseases in Japan. Findings suggest that early SGLT2i treatment may be beneficial in preventing DR development in early-stage T2DM. Graphical abstract available for this article.

Bilateral vitrectomy in patients with proliferative diabetic retinopathy-characteristics and surgical outcomes

PURPOSE

Comparing characteristics and outcomes of patients with bilateral proliferative diabetic retinopathy (PDR) undergoing concurrent and sequential vitrectomy.

METHODS

Patients having bilateral vitrectomy were classified into concurrent (requiring bilateral surgery simultaneously) and sequential (indicating vitrectomy in one eye later) groups. Clinical characteristics and outcomes were compared, and correlation between the first and second-operated eyes was analyzed.

RESULTS

One hundred eight and 126 eyes were in the concurrent and sequential groups, respectively. The sequential group was older (50 vs. 45 years, P = 0.017), had less retinal detachment (54 vs. 77%, P < 0.001), and better visual outcomes (0.79 vs. 1.30, P = 0.021), especially the second-operated eyes. The concurrent group had weaker correlations of disease severity (phi coefficient: 0.36 vs. 0.61) and post-operative visual acuity (r: 0.12 vs. 0.34) between the first- and second-operated eyes than the sequential group. Prior intravitreal injection of anti-vascular endothelial growth factor (odds ratio [OR] 0.37, 95% confidence interval [CI] 0.15-0.86, P = 0.025) predicted better outcomes, while post-operative neovascular glaucoma predicted worse outcomes (OR 6.5, 95% CI 1.7-27.9, P = 0.008).

CONCLUSIONS

PDR patients requiring surgery concurrently were younger and had more severe diseases and worse outcomes. However, poor outcomes in the first eye did not predict similar outcomes in the second eye.

Clinical Characteristics and Surgical Outcomes of Patients Undergoing Pars Plana Vitrectomy for Proliferative Diabetic Retinopathy

OBJECTIVE

To evaluate clinical characteristics impacting surgical outcomes of patients undergoing pars plana vitrectomy (PPV) for complications of proliferative diabetic retinopathy (PDR).

DESIGN

Retrospective consecutive observational case series of patients at a large county hospital in Dallas, Texas, from 2014 to 2019.

SUBJECTS

Seven hundred thirty-two patients (933 eyes) undergoing PPV for PDR complications.

METHODS

Collected data included demographics, surgical indication, adjuvant therapies, intraoperative course, complications, and best corrected visual acuity (BCVA). Patients with < 6 months of follow-up were excluded. Best corrected visual acuity was converted to logarithm of the minimum angle of resolution for analysis. Statistics performed included t test, analysis of variance, and multivariate analyses.

MAIN OUTCOME MEASURES

Postoperative BCVA, primary anatomic success rate, and postoperative complications.

RESULTS

Three hundred ninety-three patients were male (509 eyes; 54.5%) with an average age of 52 years. Postoperative BCVA at 6 months was significantly different among surgical indications: 0.79 versus 0.77 versus 1.20 (P < 0.0001) for vitreous hemorrhage (VH), vitreomacular interface abnormalities, and tractional retinal detachment (TRD), respectively. Adjuvant preoperative therapy with panretinal photocoagulation (PRP) versus no PRP (0.95 vs. 1.25; P < 0.001) and insulin versus no insulin (0.99 vs. 1.17; P < 0.01) were associated with improved vision. Iatrogenic breaks were associated with decreased postoperative vision (1.40 vs. 0.88; P < 0.001). The primary anatomic success rate for TRD was 85% (495 eyes). Combined TRD/RRD (tractional and rhegmatogenous retinal detachment) was associated with a lower success rate compared with macula-on/macula-off TRD, with odds ratios of 0.36, 0.46, and 0.53, respectively. Patients experiencing recurrent detachment postsurgery had worse preoperative visual acuity (VA) (1.93 vs. 1.63; P < 0.01) and were younger (47.6 vs. 50.0; P = 0.02). Postoperative complications occurred in 699 eyes (75%), with VH (498 eyes, 53%), cataract (465, 50%), and elevated intraocular pressure (149, 16%) being the most common. Two hundred thirty-six eyes (25%) required a second PPV operation. Endophthalmitis (1 eye; <1%) and choroidal detachment (5 eyes; <1%) were rare.

CONCLUSIONS

In this retrospective series analyzing surgical outcomes among patients with complications from PDR, vitrectomy led to improved vision on average, with a meaningful proportion of patients receiving additional surgical intervention. Surgical indication, presenting VA, age, and adjuvant therapies appeared to impact outcomes.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

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.

Clinical Outcomes of 27-Gauge Pars Plana Vitrectomy for Diabetic Tractional Retinal Detachment Repair

Purpose: To analyze the clinical outcomes of 27-gauge pars plana vitrectomy (PPV) repair of diabetic tractional retinal detachment (TRD) of various severities. Methods: This retrospective case series examined the outcomes of 27-gauge PPV to repair diabetic TRD from 2016 to 2020. The effect of medical and ophthalmologic history parameters and baseline detachment characteristics on visual acuity (VA) and retinal reattachment was analyzed. A grading system was established to stage the severity of the baseline vitreoretinal traction or detachment and compare the visual and anatomic outcomes between stages. Results: The study comprised 79 eyes (79 patients). The overall redetachment rate was 10.1% (8/79). The proportion of eyes with severe visual impairment (worse than 20/200) decreased from 81.0% (64/79) preoperatively to 56.9% (37/65) 6 months postoperatively (P < .001). Worse preoperative logMAR VA was associated with greater odds of redetachment (P = .017) and worse postoperative VA (P < .001). Insulin dependence was associated with better VA at 6 months (P = .017). A shorter known duration of diabetes (P = .026) and evidence of neovascularization of the iris (NVI) or angle (P = .004) were associated with worse visual outcomes. Eyes with detachment involving the posterior pole extending beyond the equator had worse VA at 6 months (P = .048). Conclusions: The primary reattachment rate after 27-gauge PPV was 89.9%. There was significant VA improvement, with a roughly 40% reduction in the number of eyes with severe visual impairment by the final follow-up. Insulin dependence, duration of diabetes, presence of NVI before surgery, and baseline posterior pole detachment extending beyond the equator were predictors of visual outcomes.

Long-term outcomes of administration of intravitreal triamcinolone acetonide after posterior vitreous detachment during pars plana vitrectomy for proliferative diabetic retinopathy

AIM

To evaluate the long-term outcomes of intravitreal triamcinolone acetonide (TA) administration after posterior vitreous detachment (PVD) during pars plana vitrectomy (PPV) for patients with proliferative diabetic retinopathy (PDR).

METHODS

A total of 189 eyes (152 patients) who underwent PPV for severe PDR were reviewed. Intravitreal injection of TA (IVTA) was administered during PPV in 118 eyes (PPV+IVTA group), and 71 eyes did not receive IVTA (PPV group). Immediately after PVD, when most of the vitreous and proliferative membranes were removed, 0.1 mL TA (40 mg/mL) was injected into the vitreous cavity in the PPV+IVTA group. All patients were followed-up for least 12 months. Visual outcomes and postoperative complications were recorded and compared between the two groups.

RESULTS

IVTA was helpful for proliferative membrane peeling and haemostasis during PPV. In the PPV+IVTA group, best-corrected visual acuity had significantly improved and the intraocular pressure was controlled well during the follow-up. The incidence of early recurrent vitreous haemorrhage after PPV was significantly lower in the PPV+IVTA group (1.7%) than in the PPV group (9.9%) (p=0.028).

CONCLUSION

The administration of IVTA after PVD during PPV can effectively improve the final visual outcomes and prevent postoperative complications in patients with severe PDR.

Salivary Exosomes in Health and Disease: Future Prospects in the Eye

Exosomes are a group of vesicles that package and transport DNA, RNA, proteins, and lipids to recipient cells. They can be derived from blood, saliva, urine, and/or other biological tissues. Their impact on several diseases, such as neurodegenerative, autoimmune, and ocular diseases, have been reported, but not fully unraveled. The exosomes that are derived from saliva are less studied, but offer significant advantages over exosomes from other sources, due to their accessibility and ease of collection. Thus, their role in the pathophysiology of diseases is largely unknown. In the context of ocular diseases, salivary exosomes have been under-utilized, thus creating an enormous gap in the literature. The current review discusses the state of exosomes research on systemic and ocular diseases and highlights the role and potential of salivary exosomes as future ocular therapeutic vehicles.

A pilot study of viscoelastic agent to prevent recurrent vitreous hemorrhage after vitrectomy for proliferative diabetic retinopathy

BACKGROUND

To evaluate the possibilty of preventing recurrent vitreous hemorrhage (RVH) after vitrectomy in proliferative diabetic retinopathy (PDR) patients with unabsorbed vitreous hemorrhage (VH) by intravitreal injection of viscoelastic agent (VA) at the end of the surgery and compared its effect with triamcinolone acetonide (TA).

METHODS

This was a pilot prospective, observational study. PDR patients with VH who underwent vitrectomy were assigned to 3 groups according to the tamponade applicated at the end of the surgery, including VA group (intravitreally injected 1 ml VA if the retina was prone to bleed during the operation), TA group (intravitreally injected 2 mg TA when there was much exudates), or balanced salt solution (BSS) group (no tamponade). Then postoperative follow-up was performed routinely until 6 months after surgery. The primary outcome was the incidence of RVH, secondary outcome were the best-corrected visual acuity (BCVA) and introcular pressure (IOP). Cataract formation and other complication were also assessed.

RESULTS

A total of 68 eyes, from 68 patients, were included. 18,18,32 eyes were enrolled in the VA group, TA group and BSS group, respectively. The integral incidence of RVH after vitrectomy was 5.6%, 5.6% and 12.5% respectively (P = 0.602). There was no early RVH in VA or TA group, whereas 3 early RVHs were identified in BSS group, however there was no significant difference (P = 0.171). Every group had one late RVH case. In all groups, final BCVA showed significant improvement compared to baseline. BCVA at any postoperative visit showed no significant differences among 3 groups. Mean IOP was higher 1 week after surgery in VA group compared with the other groups; however, in other times the differences were not significant. No cataract formation and other complication was noted in 3 groups.

CONCLUSION

Intravitreal injection of VA or TA at the end of vitrectomy for PDR patients with unabsorbed VH tend to reduce the incidence of early RVH after vitrectomy similarly. As VA was preferred to applicate in the eyes that were prone to bleed, intravitreal injection of VA at the end of vitrectomy might be a promising method for preventing RVH in PDR patients.

Ocular findings, surgery details and outcomes in proliferative diabetic retinopathy patients with chronic kidney disease

Purpose

We investigated the influence of impaired renal function on fundus characteristics, pars-plana vitrectomy (PPV) details, and outcomes in patients with proliferative diabetic retinopathy (PDR).

Design

A retrospective cohort study

Methods

We investigated a consecutive series of PDR patients who underwent PPV. The diabetic complications, previous photocoagulation, intravitreal injections before PPV, ocular findings during PPV, surgical details, short-term visual outcome and post-PPV complications were recorded and compared between patients with and without impaired renal function.

Results

149 patients had normal renal function (67.7%), and 71 (32.3%) patients had impaired renal function; 85.4% of patients were identified with chronic kidney disease (CKD) during the preoperative assessment. Impaired renal function was related to hypertension (3.40[1.58–7.29], p = 0.002), incomplete pan-retinal photocoagulation (PRP) (3.18[1.50–6.72], p = 0.002), severe fibrovascular membrane (8.19[3.43–19.54], p<0.001), and extensive retinal vascular closure (3.40[1.54–7.52], p = 0.002). There was a more frequent occurrence of severe intraoperative bleeding (56.3%, 32.2%, p = 0.001) and a higher percentage of intraocular subretinal fluid drainage (45.1%, 22.1%, p = 0.008) in patients with impaired renal function. The percentage of patients whose visual acuity (VA) increased was similar between the two groups (42.3%, 54.4%, p = 0.34).

Conclusions

In PDR patients, screening for CKD was required before PPV. PDR patients with impaired renal function tended to have more severe ischemic retinal conditions. Comparable PPV outcomes could be obtained in patients with and without impaired renal damage.

A Paradigm Shift in the Management Approaches of Proliferative Diabetic Retinopathy: Role of Anti-VEGF Therapy

Diabetic retinopathy (DR) is considered one of the leading causes of vision loss globally. It principally causes upregulation of pro-angiogenic, proinflammatory, and vascular permeability factors such as vascular endothelial growth factor (VEGF), leading to neovascularisation. The advanced stage of DR or proliferative diabetic retinopathy (PDR) is of more concern, as it leads to vitreous haemorrhage and traction retinal detachment. Various risk factors associated with PDR include hyperglycemia, hypertension, neuropathy, dyslipidemia, anaemia, nephropathy, and retinal complications of drugs used for diabetes. Current management approaches for PDR have been stratified and involve pan-retinal photocoagulation, vitrectomy, and anti-VEGF agents. Given the emerging role of anti-VEGF agents as a favourable adjunct or alternative therapy, they have a critical role in the management of PDR. The review emphasises current management approaches for PDR focusing on anti-VEGF therapy. The review also highlights the risk/benefit evaluation of the various approaches employed for PDR management in various clinical scenarios.

An update on the management of diabetic tractional retinal detachment

Background: Tractional retinal detachment (TRD) occurs when contractile forces in the vitreous and neovascular tissue lead to the detachment of the neurosensory retina. The pre-operative use of antivascular endothelial growth factor (anti-VEGF) and advances in microsurgical instrumentation, such as a small gauge vitrectomy (SGV), have improved surgical outcomes.Aim: The purpose of this review is to highlight recent trends in the management of diabetic TRD, supporting earlier surgical intervention and the expanded surgical indications.Methods: PubMed was searched for the following terms: ‘diabetes’ OR ‘diabetic retinopathy’ AND ‘TRD’ AND ‘pars plana vitrectomy (PPV)’ AND ‘anti-VEGF’ AND ‘endophotocoagulation’. Reference lists were reviewed for additional articles. The review was focused on all articles later than 2010 for recent updates on the ever-changing management of this disease entity. No case reports were included in this review article.Results: Management of TRD continues to remain challenging, despite the recent advancements in techniques and instrumentation. Each case needs to be individualised, with careful pre-operative planning, understanding of patient expectations and counselling, coupled with meticulous surgical skills and diligent postoperative management.Conclusion: Management of TRD continues to remain challenging despite recent advances in techniques and instrumentation. Vitrectomy for TRD can improve vision-related quality of life, and the continued evolution and improvement in surgical techniques and adjunctive pharmacotherapy will most likely continue to improve postoperative outcomes.Contribution: The paper presents an overview of current management of tractional retinal detachment in patients with advanced proliferative diabetic retinopathy. 

Angiogenic footprints in diabetic retinopathy: opportunities for drug development

Diabetic retinopathy is one of the withering disorders that has been making the lives of patients miserable. Arising as a result of chronic high blood sugar levels in diabetes patients, retinopathy has become a major reason causing permanent blindness, retinal detachment, vitreous humor, rage, or glaucoma among patients. Angiogenesis being the major culprit behind the development of this condition is the growth of new blood vessels from the earlier ones existing. The abnormal growth and poor development of blood vessels also lead to aggravation of the conditions, with vascular endothelial growth factor (VEGF) playing a major role in the process. Various anti-angiogenic therapies or anti-VEGF therapies are being explored for the treatment of this condition. 4 widely explored drugs being-Bevacizumab, pegaptanib sodium, ranibizumab, and aflibercept. The review article tries to summarize studies illustrating the efficacy of these drugs in the treatment of diabetic retinopathy along with some of the herbal therapeutic paradigms displaying anti-angiogenic action that is being used to treat this condition.

Impact of Early COVID-19 Pandemic on Common Ophthalmic Procedures Volumes: A US Claims-Based Analysis

PURPOSE

The COVID-19 pandemic has had a profound effect on the delivery of healthcare in the United States and globally. The aim of this study was to evaluate the impact of COVID-19 on common ophthalmic procedure utilization and normalization to pre-pandemic daily rates.

METHODS

Leveraging a national database, Clinformatics™ DataMart (OptumInsight, Eden Prairie, MN), procedure frequencies and daily averages, defined by Current Procedural Terminology codes, of common elective and non-elective procedures within multiple ophthalmology sub-specialties were calculated. Interrupted time-series analysis with a Poisson regression model and smooth spline functions was used to model trends in pre-COVID-19 (January 1, 2018-February 29, 2020) and COVID-19 (March 1, 2020-June 30, 2020) periods.

RESULTS

Of 3,583,231 procedures in the study period, 339,607 occurred during the early COVID-19 time period. Anti-vascular endothelial growth factor injections (44,412 to 39,774, RR 1.01, CI 0.99-1.02; p = .212), retinal detachment repairs (1,290 to 1,086, RR 1.07, CI 0.99-1.15; p = .103), and glaucoma drainage implants/trabeculectomies (706 to 487, RR 0.93, CI 0.83-1.04; p = .200) remained stable. Cataract surgery (61,421 to 33,054, RR 0.77; CI 0.76-0.78; p < .001), laser peripheral iridotomy (1,875 to 890, RR 0.82, CI 0.76-0.88; p < .001), laser trabeculoplasty (2,680 to 1,753, RR 0.79, CI 0.74-0.84; p < .001), and blepharoplasty (1,522 to 797, RR 0.71, CI 0.66-0.77; p < .001) all declined significantly. All procedures except laser iridotomy returned to pre-COVID19 rates by June 2020.

CONCLUSION

Most ophthalmic procedures that significantly declined during the COVID-19 pandemic were elective procedures. Among these, the majority returned to 2019 daily averages by June 2020.

Incidence of and Risk Factors for Postoperative Hyphema After 23-Gauge Pars Plana Vitrectomy for Proliferative Diabetic Retinopathy

Purpose

We aim to investigate the incidence, clinical course, and risk factors for developing postoperative hyphema after 23-gauge pars plana vitrectomy (PPV) for patients with proliferative diabetic retinopathy (PDR) without neovascularization of the iris or angles and neovascular glaucoma (NVG).

Methods

This retrospective study included 155 consecutive eyes from 124 patients with at least three-month follow-up who underwent PPV for PDR without neovascularization of the iris or angles and NVG. Demographic data, surgery notes, postoperative hyphema assessment, intraocular pressure (IOP), and the surgical outcome were recorded.

Results

Postoperative hyphema occurred in 18 of 155 eyes (11.6%), with 14 of those having hyphema on day 1, and 4 having hyphema on days 7–20. Of the 18 eyes, only 3 (16.7%) had normal IOP, and immediate intraocular hypertension was observed in 15 (83.3%). Seven eyes required anterior chamber paracentesis and five needed anterior chamber irrigation. The average time for absorption of the hyphema was 13.1 days, and IOP was controlled in all cases. There was a significant correlation between membrane removal and the development of hyphema (OR = 5.65 and 95% CI: 1.190–25.203; p = 0.013). No recurrence of hyphema was observed. In patients with hyphema, the final best corrected visual acuity (BCVA) was 1.75 ± 0.84 logMAR, which improved significantly compared to the initial BCVA of 2.20 ± 0.65 logMAR (t = 3.893; p = 0.001), and the final anatomic success rate was 100%.

Conclusion

The development of hyphema is not uncommon after PPV for patients with PDR without neovascularization of the iris or angles and NVG, and membrane removal is a risk factor for postoperative hyphema. The timely management of hyphema ensures that hyphema does not affect the visual recovery or the final anatomical success.

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.

Human amniotic membrane grafts for retinal breaks in diabetic tractional retinal detachment and combined tractional and rhegmatogenous retinal detachment

To describe the surgical outcomes of using human amniotic membrane (hAM) grafts in the management of retinal breaks in diabetic tractional detachment (TRD) and combined tractional and rhegmatogenous retinal detachment (CTRRD). A retrospective case series of 10 eyes with TRD or CTRRD receiving pars plana vitrectomy with hAM grafts implantation, compared with 13 controls receiving the same surgery without hAM grafts. Best-corrected visual acuity (BCVA) and re-detachment rate were compared between two groups. Postoperatively, all eyes in the hAM group had retina attachment without recurrence, while 9 eyes in the control group had retina re-detachment and required additional surgery (0% vs 69.2%, p = 0.003). The BCVA significantly improved in the hAM group (from 1.96 ± 0.95 to 1.44 ± 0.77 in log MAR, p = 0.03), but not improved in control group (p = 0.20). Postoperative optical coherence tomography of the eyes receiving hAM grafts demonstrated glial tissue regeneration and restoration of ellipsoid zone. In diabetic TRD or CTRRD, hAM grafts could be an effective method, with promising outcome. Compared to standard surgery, it could result in higher retina reattachment rate and significant visual improvement. Moreover, it may offer the adjunctive benefit in tissue regeneration and fasten ellipsoid zone restoration.

Comparison Between Graders in Detection of Diabetic Neovascularization With Swept Source Optical Coherence Tomography Angiography and Fluorescein Angiography

PURPOSE

We compared the ability of ophthalmologists to identify neovascularization (NV) in patients with proliferative diabetic retinopathy using swept-source optical coherence tomography angiography (SS-OCTA) and fluorescein angiography (FA).

DESIGN

Retrospective study comparing diagnostic instruments.

METHODS

Eyes with proliferative diabetic retinopathy or severe nonproliferative diabetic retinopathy and a high suspicion of NV based on clinical examination were imaged using SS-OCTA and FA at the same visit. Two separate grading sets consisting of scrambled, anonymized SS-OCTA and FA images were created. The ground truth for presence of NV was established by consensus of 2 graders with OCTA experience who did not participate in the subsequent assessment of NV in this study. The 2 anonymized image sets were graded for presence or absence of NV by 12 other graders that included 2 residents, 6 vitreoretinal fellows, and 4 vitreoretinal attending physicians. The percentage of correct grading of NV using SS-OCTA and FA was assessed for each grader and across grader training levels.

RESULTS

Forty-seven eyes from 24 patients were included in this study. Overall, the mean percentage of correct NV grading was 87.8% using SS-OCTA with B-scans and 86.2% using FA (P = .92). Assessing each grader individually, there was no statistically significant asymmetry in correct grading using SS-OCTA and FA.

CONCLUSIONS

Ophthalmologists across training levels were able to identify diabetic NV with equal accuracy using SS-OCTA and FA. Based on these results, SS-OCTA may be an appropriate standalone modality for diagnosing diabetic NV.

βA1-crystallin regulates glucose metabolism and mitochondrial function in mouse retinal astrocytes by modulating PTP1B activity

βA3/A1-crystallin, a lens protein that is also expressed in astrocytes, is produced as βA3 and βA1-crystallin isoforms by leaky ribosomal scanning. In a previous human proteome high-throughput array, we found that βA3/A1-crystallin interacts with protein tyrosine phosphatase 1B (PTP1B), a key regulator of glucose metabolism. This prompted us to explore possible roles of βA3/A1-crystallin in metabolism of retinal astrocytes. We found that βA1-crystallin acts as an uncompetitive inhibitor of PTP1B, but βA3-crystallin does not. Loss of βA1-crystallin in astrocytes triggers metabolic abnormalities and inflammation. In CRISPR/cas9 gene-edited βA1-knockdown (KD) mice, but not in βA3-knockout (KO) mice, the streptozotocin (STZ)-induced diabetic retinopathy (DR)-like phenotype is exacerbated. Here, we have identified βA1-crystallin as a regulator of PTP1B; loss of this regulation may be a new mechanism by which astrocytes contribute to DR. Interestingly, proliferative diabetic retinopathy (PDR) patients showed reduced βA1-crystallin and higher levels of PTP1B in the vitreous humor.

Factors correlated with visual outcomes at two and four years after vitreous surgery for proliferative diabetic retinopathy

Proliferative diabetic retinopathy (PDR) is the most severe case of diabetic retinopathy that can cause visual impairment. This study aimed to reveal the factors correlated with better postoperative visual acuity after a long follow-up in patients who underwent vitrectomy for PDR. We retrospectively analyzed the data set including systemic findings, ocular findings, and surgical factors from registered patients who could be completely followed up for 2 or 4 years after vitrectomy. We ultimately enrolled 128 eyes from 100 patients who underwent vitrectomy for PDR between January 2008 and September 2012 and were followed up for >2 years. Among them, 91 eyes from 70 patients could be followed up for 4 years. Factors related to the postoperative visual acuity of ≥20/40 and ≥20/30 after 2 and 4 years were investigated by logistic regression analysis. Better postoperative visual acuity correlated with the following factors: no rubeosis iridis ([≥20/40 at 2 years; odds ratio {OR}, 0.068; 95% confidence interval {CI}, 0.012–0.39; P = 0.003], [≥20/30 at 2 years; OR, 0.07; 95% CI, 0.01–0.40; P = 0.03], [≥20/30 at 4 years; OR, 0.078; 95% CI, 0.006–0.96; P = 0.04]), no fibrovascular membrane [(≥20/40 at 2 years; OR, 0.22; 95% CI, 0.061–0.81; P = 0.02), (≥20/40 at 4 years; OR, 0.26; 95% CI, 0.07–0.94; P = 0.04), (≥20/30 at 4 years; OR, 0.14; 95% CI, 0.04–0.52; P = 0.004)], existing vitreous hemorrhage (≥20/30 at 2 years; OR, 9.55; 95% CI, 1.03–95.27; P = 0.04), and no reoperation ([≥20/40 at 4 years; OR, 0.15; 95% CI, 0.03–0.78; P = 0.02], [≥20/30 at 4 years; OR, 0.06; 95% CI, 0.07–0.54; P = 0.01]). Treatment provision before disease severity and treatment without complications were associated with good postoperative visual acuity.

Pars Plana Vitrectomy for Full-Thickness Macular Holes in Patients with Proliferative Diabetic Retinopathy and Active Fibrovascular Proliferation

Purpose of the Study

To study preoperative and postoperative optical coherence tomography features and the outcomes of pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling for full-thickness macular holes (MHs) associated with proliferative diabetic retinopathy.

Methods

The data from 14 eyes of 11 patients with full-thickness macular holes and active diabetic fibrovascular proliferation (FVP) with/without tractional retinal detachment who underwent pars plana vitrectomy and standard ILM peeling at Zarifa Aliyeva National Ophthalmology Centre in Baku were analysed. Bilateral surgery for diabetic MHs was performed in 27.3% of patients. The minimum follow-up duration was 6 months.

Results

All eyes (100%) achieved type 1 macular hole closure, with residual macular subretinal fluid (SRF) present in 13 cases after surgery (92.9%). The SRF resolved gradually without any interventions. The incidence of SRF was 92.9% at 1 month, 85.7% at 3 months, 50% at 6 months, and 14.3% at 9 months (Cochran's Q test, χ2 (4) =37.44, p<0.001). Visual acuity improved after surgery in 13 cases (92.9%), with a mean difference of 0.75 ±0.71 LogMAR between the preoperative and final values, r_s=0.608, 95% BCa CI [0.037-0.969], p=0.021.

Conclusion

The standard ILM peeling technique for full-thickness MHs in eyes with active diabetic fibrovascular proliferation can help restore the anatomy and function of the macula in diabetic patients. Close follow-up is important for unilateral cases. Residual SRF in the perifoveal area is detectable by OCT after surgery in patients with macular holes associated with diabetic tractional retinal detachment, and it usually resorbs gradually without any interventions.

Characteristics and outcomes of vitrectomy for proliferative diabetic retinopathy in young versus senior patients

Background

Proliferative diabetic retinopathy (PDR) is one of the most common cause of vision loss in diabetic patients, and the incidence age of PDR patients gradually gets younger. This study aims to compare the characteristics of PDR and outcomes following vitrectomy in young and senior patients.

Methods

This is a retrospective case series study. Data of 116 eyes of 92 patients who underwent vitrectomy for PDR from February 2012 to February 2017 were reviewed, which were divided into young and senior patient groups. All patients were followed up for 24 months at least.

Results

There were 62.1% of eyes with tractional retinal detachment secondary to PDR in the young patient group, while only 12.1% of eyes in the senior patient group with this surgery indication. (P < 0.001) The best corrected visual acuity increased in 41 eyes (70.7%), stable in 9 eyes (15.5%), and decreased in 8 eyes (13.8%) in young patients at the final follow-up. And it increased in 47 eyes (81.0%), stable in 2 eyes (3.4%), and decreased in 9 eyes (15.5%) in senior patients.(P = 0.085) Postoperative complications mainly included recurrent vitreous hemorrhage (24.1%), retinal detachment (3.4%), neovascular glaucoma (NVG) (27.6%) and nuclear sclerosis (53.4%) in young patients, and it was 19.0, 0.0, 1.7 and 3.4% in senior patients respectively.

Conclusion

PDR of young patients is more severe than that of senior patients, and vitrectomy is an effective and safe method for PDR treatment. NVG is a main and severe complication besides nuclear sclerosis in young patients, and the incidence of NVG is higher compared to that in senior patients.

Persistent subretinal fluid following diabetic tractional retinal detachment repair: risk factors, natural history, and management outcomes

PURPOSE

To study the natural history, anatomical and functional outcomes of persistent subretinal fluid (SRF) after pars plana vitrectomy (PPV) for diabetic tractional retinal detachment (TRD) and combined traction-rhegmatogenous retinal detachment (TRRD).

METHODS

Retrospective interventional case series of 43 patients (46 eyes) with persistent SRF following PPV for diabetic TRD or combined TRRD from January 2010 to December 2017 at single tertiary institution. Primary outcomes included best corrected visual acuity (BCVA) and central foveal thickness (CFT).

RESULTS

Thirty-one eyes (67.4%) had macula-off TRD, 5 (10.9%) had fovea-threatening TRD and 10 (21.7%) had combined TRRD. The mean (± SD) duration of decreased vision was 48.0 ± 58.2 weeks. The mean follow-up duration was 21 ± 13.2 months. Residual macular SRF was detected by optical coherence tomography in all eyes at 3 months and in 10 eyes (23.8%) at 12 months after surgery. Only 3 eyes (6.5%) had persistent SRF at final follow up. The mean time to resolution was 10.6 ± 4.1 months [range 6.0-23.0]. Thirteen eyes received additional intervention to address SRF. The mean CFT gradually improved until final follow-up (P-value < 0.001). The mean BCVA improved from 1.62 ± 0.88 LogMAR at presentation to 1.05 ± 0.76 LogMAR at final follow up. No statistically significant difference in final BCVA was found between eyes that had intervention and eyes that were observed (P value = 0.762).

CONCLUSION

Persistent SRF after diabetic vitrectomy resolves slowly over time with gradual improvement in visual acuity. Additional drainage of persistent SRF may not be necessary.

Recurrent retinal detachment after diabetic vitrectomy

PURPOSE

To investigate the characteristics of recurrent retinal detachment (RD) after diabetic vitrectomy (DV).

METHODS

Consecutive cases underwent vitrectomy for recurrent RD after DV was collected and separated into the following four groups for analysis: rhegmatogenous RD (RRD), pure tractional RD (Proliferative Subgroup 1), combined RD with proliferative tissue within the equator (Proliferative Subgroup 2), and combined RD with both posterior and peripheral proliferations (Proliferative Subgroup 3).

RESULTS

Of the 41 cases enrolled, retinal reattachment was achieved in 73.2%. Over all, visual acuity was statistically better after operation (p = 0.001). All cases in the RRD group (four cases) had reattachment and a better final vision (p = 0.008). In the proliferative subgroups, those with pure tractional RD (Subgroup 1, seven cases) had the best visual acuity at the time of recurrent RD (p = 0.002). Subgroups 2 and 3 showed statistically significant better final visual acuity (p = 0.045 and 0.019, respectively). Poor preoperative vision (p = 0.001), non-attachment (p = 0.004), and neovascular glaucoma (p = 0.001) were associated with poor prognosis.

CONCLUSIONS

Visual acuity may improve after operation for recurrent RD after diabetic vitrectomy. Visual prognosis was better in cases with pure RRD. In the proliferative subgroups, vision was impaired by the development of neovascular glaucoma and retinal non-attachment.

Ghost cell glaucoma after intravitreous injection of ranibizumab in proliferative diabetic retinopathy

Background

The development of ghost cell glaucoma in patients with proliferative diabetic retinopathy (PDR) after intravitreous injection (IV) was rare. Here we reported a series of patients with PDR who received Intravitreous Ranibizumab (IVR) and developed ghost cell glaucoma and analyzed the potential factors that might be related to the development of ghost cell glaucoma.

Methods

Retrospective case series study. The medical records of 71 consecutive eyes of 68 PDR patients who received vitrectomy after IVR from January 2015 to January 2017 were reviewed. The development of ghost cell glaucoma after IVR was recorded. Characteristics of enrolled patients were retrieved from their medical charts. Factors associated with ghost cell glaucoma were compared between eyes with the development of ghost cell glaucoma and eyes without the development of ghost cell glaucoma. Variables were further enrolled in a binary backward stepwise logistic regression model, and the model that had the lowest AIC was chosen.

Results

There were 8 out of 71 eyes of the PDR patients developed ghost cell glaucoma after they received IVR. The interval between detection of elevation of intraocular pressure (IOP) and IV ranged from 0 to 2 days. Among them, after IVR, there were two eyes had IOP greater than 30 mmHg within 30 min, four eyes showed normal IOP at 30 min, and then developed ghost cell glaucoma within 1 day, two eyes developed ghost cell glaucoma between 24 and 48 h. The mean IOP was 46.5 ± 8.0 mmHg. All patients gained normal IOP after vitrectomy without medicine for lowering IOP. The presence of ghost cell glaucoma was associated with tractional retinal detachment (RR = 4.60 [2.02 ~ 8.48], p = 0.004) and fibrovascular membrane involving disk (RR = -3.57 [− 7.59 ~ − 0.92], p = 0.03) (AIC = 39.23, AUC = 0.88) in a logistic regression model.

Conclusion

Attention to postoperative IOP should be paid to patients with PDR undergoing vitrectomy who receive a preoperative IV of anti-VEGF agents. PDR patients with tractional retinal detachment or fibrovasucular membrane involving optic disc are more likely to develop ghost cell glaucoma after IV.

MiR-203a-3p inhibits retinal angiogenesis and alleviates proliferative diabetic retinopathy in oxygen-induced retinopathy (OIR) rat model via targeting VEGFA and HIF-1α

Proliferative diabetic retinopathy (PDR) is a common complication of diabetes mellitus, characterized by abnormal retinal angiogenesis. MicroRNA-203-3p (miR-203-3p) was found to be down-regulated in a murine model of proliferative retinopathy. This study was performed to explore the role of miR-203a-3p in retinal angiogenesis of PDR. Firstly, a rat OIR model, which was used to mimic PDR, was established and the OIR rats were treated with scrambled control or miR-203a-3p agomir by intravitreal injection. The results showed that the level of miR-203a-3p was decreased in OIR rats, and forced over-expression of miR-203a-3p inhibited OIR-induced retinal angiogenesis as evidenced by reduced blood vessel profiles and CD31 expression. OIR-induced up-regulation of VEGFA, HIF-α, PCNA, and MMPs in the retina was also counteracted by miR-203a-3p. Additionally, high glucose (HG)-induced proliferation, migration and tube formation of human retinal microvascular endothelial cells (HRMECs) were also dampened by the up-regulation of miR-203a-3p. Dual-luciferase reporter assay showed that miR-203a-3p could specifically bind to the 3'UTR of VEGFA and HIF-1α. Over-expression of VEGFA or HIF-1α restored the tube formation activity of HRMECs suppressed by miR-203a-3p. In conclusion, our findings demonstrate that up-regulation of miR-203a-3p might inhibit pathological retinal angiogenesis of PDR by targeting VEGFA and HIF-1α.

Involvement of TRPV1 and TRPV4 Channels in Retinal Angiogenesis

Purpose

We investigate the contribution of TRPV1 and TRPV4 channels to retinal angiogenesis.

Methods

Primary retinal microvascular endothelial cells (RMECs) were used for RT-PCR, Western blotting, immunolabeling, Ca2+ signaling, and whole-cell patch-clamp studies while localization of TRPV1 also was assessed in retinal endothelial cells using whole mount preparations. The effects of pharmacologic blockers of TRPV1 and TRPV4 on retinal angiogenic activity was evaluated in vitro using sprout formation, cell migration, proliferation, and tubulogenesis assays, and in vivo using the mouse model of oxygen-induced retinopathy (OIR). Heteromultimerization of TRPV1 and TRPV4 channels in RMECs was assessed using proximity ligation assays (PLA) and electrophysiologic recording.

Results

TRPV1 mRNA and protein expression were identified in RMECs. TRPV1 labelling was found to be mainly localized to the cytoplasm with some areas of staining colocalizing with the plasma membrane. Staining patterns for TRPV1 were broadly similar in endothelial cells of intact vessels within retinal flat mounts. Functional expression of TRPV1 and TRPV4 in RMECs was confirmed by patch-clamp recording. Pharmacologic inhibition of TRPV1 or TRPV4 channels suppressed in vitro retinal angiogenesis through a mechanism involving the modulation of tubulogenesis. Blockade of these channels had no effect on VEGF-stimulated angiogenesis or Ca2+ signals in vitro. PLA and patch-clamp studies revealed that TRPV1 and TRPV4 form functional heteromeric channel complexes in RMECs. Inhibition of either channel reduced retinal neovascularization and promoted physiologic revascularization of the ischemic retina in the OIR mouse model.

Conclusions

TRPV1 and TRPV4 channels represent promising targets for therapeutic intervention in vasoproliferative diseases of the retina.

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.

Association between disorganization of retinal inner layers and visual acuity after proliferative diabetic retinopathy surgery

We report to evaluate if disorganization of the retinal inner layers (DRIL) obtained by swept-source optical coherence tomography (SS-OCT) predicts the postoperative best-corrected visual acuity (BCVA) to treat proliferative diabetic retinopathy (PDR). Twenty-one eyes of 21 patients who underwent vitrectomy for PDR were studied retrospectively. BCVA and SS-OCT images were obtained until 6 months postoperatively. The associations between BCVA and SS-OCT parameters measured in a 1-mm central foveal area were evaluated. The DRIL length, external limiting membrane disruption, and ellipsoid zone (EZ) disruption 1 month postoperatively were associated positively with the postoperative logarithm of the minimum angle of resolution (logMAR) BCVA at 1, 3, and 6 months (1 month, p = 0.009, p = 0.013, p = 0.001; 3 months, p = 0.03, p = 0.021, p = 0.002; and 6 months, p = 0.021, p = 0.013, and p = 0.005, respectively). The eyes with a 500-µm or longer DRIL 1 month postoperatively (19%, 4/21 eyes) had significantly worse VA at 1, 3, and 6 months postoperatively (p = 0.007, p = 0.008, and p = 0.020, respectively). Multilinear regression analysis of all visits until 6 months postoperatively showed that the DRIL was correlated more significantly (p = 0.0004) with logMAR BCVA than the disrupted EZ length. The DRIL in the early postoperative period may predict the visual outcomes after treating PDR.

Beneficial visual outcome of vitrectomy and delamination surgery for tractional complications of diabetic retinopathy in a cohort of black patients

BACKGROUND/AIMS

Poor visual outcomes have recently been reported in black patients undergoing vitrectomy and delamination surgery for complications of proliferative diabetic retinopathy. We therefore investigated the outcome of surgery on a similar cohort of black patients and examined for potential predictors of visual success.

METHODS

A single-centre retrospective case review of consecutive black patients who underwent vitrectomy and delamination surgery for complications of PDR between July 2010 and September 2017. The primary outcome measure was change in visual acuity (VA) at 6 months post-operatively. Multiple linear regression analysis was performed to evaluate determinants of change in VA.

RESULTS

A total of 44 eyes of 44 patients were included. Mean age was 53.7 (range: 24.3-75.8) years. In all, 43% were male. A total of 52% had adjunctive pre-operative anti-VEGF therapy. Mean pre-operative VA was 1.49 logMAR ± 0.73 (range 0.18 to 2.6 logMAR). Mean change in VA at 6 months was a gain of 0.59 ± 0.94 logMAR (range 1.9 logMAR acuity loss to 2.5 logMAR acuity gain). Four cases required further surgery to treat rhegmatogenous detachment. The acuity of 68% improved by 0.3 or more logMAR. Silicone oil was used as primary tamponade in 7%. Pre-operative VA and use of silicone oil significantly predicted VA decline at 6 months (p = 0.001 and p = 0.007).

CONCLUSIONS

The majority of our cohort derived visual benefit from vitrectomy and delamination for PDR-related complications. Improvement in VA was comparable to outcomes from the UK National Ophthalmic Database report. Silicone oil should be avoided these patients if possible.

Comparative Analysis of Three-Dimensional Heads-Up Vitrectomy and Traditional Microscopic Vitrectomy for Vitreoretinal Diseases

Purpose: To investigate the visual outcomes and occurrences of perioperative complications after three-dimensional (3D) heads-up vitrectomy compared with traditional microscopic (TM) surgery for vitreoretinal diseases. Methods: A retrospective case series comparison of 3D and TM vitrectomy performed on 124 and 202 eyes with a minimum follow-up of 6 months, respectively, by the same surgeon. Changes in visual acuity, primary anatomical success, operation time, and perioperative complications were evaluated. Results: There were no significant differences in age, gender, axial length, ocular and surgical history, surgical indication, and visual acuity between the two groups at baseline. Both groups showed a significant improvement in visual acuity at the final visit (both P < .05) and experienced comparable anatomical recoveries regarding epiretinal membranes, vitreous hemorrhage, macular holes, retinal detachment, and pathological myopic foveoschisis. The mean overall operation time was not significantly longer in the 3D group (31.0 ± 17.6 min) than the TM (31.0 ± 15.9 min) group (P = .994). The incidence rates of postoperative complications during the follow-up were similar between the 3D (30.6%) and TM groups (30.2%) (P = .932). Conclusions: The 3D and TM vitrectomy surgeries yielded comparable visual and anatomical outcomes for treatment of vitreoretinal diseases without a significant difference in the rate of complications. The 3D heads-up vitrectomy may be considered the treatment of choice for patients with various vitreoretinal diseases.

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.

VISUALIZATION FROM INTRAOPERATIVE SWEPT-SOURCE MICROSCOPE-INTEGRATED OPTICAL COHERENCE TOMOGRAPHY IN VITRECTOMY FOR COMPLICATIONS OF PROLIFERATIVE DIABETIC RETINOPATHY

PURPOSE

To evaluate the use of live volumetric (4D) intraoperative swept-source microscope-integrated optical coherence tomography in vitrectomy for proliferative diabetic retinopathy complications.

METHODS

In this prospective study, we analyzed a subgroup of patients with proliferative diabetic retinopathy complications who required vitrectomy and who were imaged by the research swept-source microscope-integrated optical coherence tomography system. In near real time, images were displayed in stereo heads-up display facilitating intraoperative surgeon feedback. Postoperative review included scoring image quality, identifying different diabetic retinopathy-associated pathologies and reviewing the intraoperatively documented surgeon feedback.

RESULTS

Twenty eyes were included. Indications for vitrectomy were tractional retinal detachment (16 eyes), combined tractional-rhegmatogenous retinal detachment (2 eyes), and vitreous hemorrhage (2 eyes). Useful, good-quality 2D (B-scans) and 4D images were obtained in 16/20 eyes (80%). In these eyes, multiple diabetic retinopathy complications could be imaged. Swept-source microscope-integrated optical coherence tomography provided surgical guidance, e.g., in identifying dissection planes under fibrovascular membranes, and in determining residual membranes and traction that would benefit from additional peeling. In 4/20 eyes (20%), acceptable images were captured, but they were not useful due to high tractional retinal detachment elevation which was challenging for imaging.

CONCLUSION

Swept-source microscope-integrated optical coherence tomography can provide important guidance during surgery for proliferative diabetic retinopathy complications through intraoperative identification of different complications and facilitation of intraoperative decision making.

Soloist performance of vitrectomy probe in proliferative diabetic retinopathy

Purpose:

To evaluate the feasibility and outcomes of the sole use of 23g pars plana vitrectomy in cases with diabetic vitreous hemorrhage with vitreoretinal traction.

Methods:

Prospective interventional case series involving patients between January 2013 and January 2018. All eyes underwent 23g pars plana vitrectomy with internal tamponade. Intraoperative parameters including ancillary instruments, the methods used for hemostasis and complications were all recorded. Postoperative parameters including anatomic success rate, functional success, and postoperative complications were recorded and analyzed. Patients were followed up for at least 12 months.

Results:

A total of 68 eyes of 66 patients were included. Intraoperative ancillary instruments were required in 5 (7.4%) eyes. None of the cases required the use of chandelier illumination, endodiathermy, or scissors. Mean best-corrected visual acuity improved significantly from LogMAR 1.67 ± 0.63 preoperative to 1.22 ± 0.38 at 1-year follow-up (P = 0.005). Functional success was achieved in 37 (54.4%) eyes at 1-year follow-up. Iatrogenic breaks occurred in 3 (4.4%) eyes, vitreous hemorrhage in 4 (5.9%) eyes, and epiretinal membranes in 3 (4.4%) eyes. Repeated vitrectomy was done in 3 (4.4%) eyes.

Conclusion:

The 23g vitrectomy probe proved to be a safe, effective, and beneficial single tool that could accomplish the diabetic vitrectomy mission exclusively with minimal aid from other instruments in cases with vitreous hemorrhage associated with vitreoretinal traction.

Vitreous rebleed following sutureless vitrectomy: Incidence and risk factors

Purpose

This study aims to evaluate the incidence and risk factors for vitreous rebleed (VRB) following 25-gauge sutureless vitrectomy for vitreous hemorrhage (VH) in diabetic retinopathy.

Methods

A retrospective review of 190 diabetic patients having undergone vitrectomy for VH at a tertiary eye care center was analyzed. Demographic data of patients along with risk factors such as blood sugar levels (BSL), blood pressure (BP), anticoagulant use, and pan-retinal photocoagulation status (PRP) were tabulated. Depending on the commencement of VRB, patients were divided into immediate rebleed-within 2 weeks and delayed rebleed-beyond 2-4 weeks.

Results

Forty-one patients had VRB, out of which 18 patients had immediate VRB and 23 patients had delayed VRB. The average duration between vitrectomy and VRB was 3.28 months. Twenty-eight patients were male and 13 were females. Average age at presentation was 53.8 years. Thirty-four patients (82.9%) were found to have high BSL and 28 patients (68.3%) had high BP and they developed rebleed (P < 0.01) after an initial hemorrhage-free period (average = 5.15 months). Fifteen patients (36.6%) underwent first time PRP intraoperatively, and they had immediate rebleed (P < 0.01) without any hemorrhage-free period (average = 0.9 months). Eight patients (19.5%) were on perioperative anticoagulants; however, their statistical significance did not persist in the multivariable model. There were neither age nor gender predilection toward rebleed (P > 0.05).

Conclusion

The incidence rate of VRB was found to be 21.6%. Age and gender did not contribute to rebleed. Intraoperative PRP was a risk factor for immediate rebleed. Poor glycemic and BP control was a risk factor for delayed rebleed.

TOMOGRAPHIC RELATIONSHIPS BETWEEN RETINAL NEOVASCULARIZATION AND THE POSTERIOR VITREOUS IN PROLIFERATIVE DIABETIC RETINOPATHY

PURPOSE

To describe anatomical relationships of retinal neovascular complexes (NVCs) and the posterior vitreous in proliferative diabetic retinopathy using spectral domain optical coherence tomography.

METHODS

Cross-sectional study. Neovascular complexes were imaged using spectral domain optical coherence tomography in 51 eyes of 37 patients. The relationship of NVCs to the posterior vitreous cortex and posterior vitreous spaces, such as the premacular bursa, prevascular vitreous fissures, and perimacular cisterns, was analyzed.

RESULTS

In the 77 NVCs evaluated, 61 (79%) had grown along the outer surface of the posterior hyaloid face, and vitreoschisis was present in 37 (48%). The "wolf's jaw" configuration was present in 9% and resulted from NVC arising from the arcades and proliferating along the posterior hyaloid face. By contrast, NVCs that invaded the bursa originated from smaller venous tributaries more distant from the arcades. The premacular bursa and prevascular vitreous fissure/perimacular cistern were invaded infrequently, respectively, in 15% and 38% (P = 0.137).

CONCLUSION

Tomographic analysis of diabetic NVCs showed that most NVCs arise and grow along the posterior hyaloid face and that vitreoschisis is more prevalent than what has been found in ultrasound studies. The wolf's jaw configuration does not seem to result from the invasion of the bursa, as previously suggested.

Rho-Kinase/ROCK as a Potential Drug Target for Vitreoretinal Diseases

Rho-associated kinase (Rho-kinase/ROCK) was originally identified as an effector protein of the G protein Rho. Its involvement in various diseases, particularly cancer and cardiovascular disease, has been elucidated, and ROCK inhibitors have already been applied clinically for cerebral vasospasm and glaucoma. Vitreoretinal diseases including diabetic retinopathy, age-related macular degeneration, and proliferative vitreoretinoapthy are still a major cause of blindness. While anti-VEGF therapy has recently been widely used for vitreoretinal disorders due to its efficacy, attention has been drawn to new unmet needs. The importance of ROCK in pathological vitreoretinal conditions has also been elucidated and is attracting attention as a potential therapeutic target. ROCK is involved in angiogenesis and hyperpermeability and also in the pathogenesis of various pathologies such as inflammation and fibrosis. It has been expected that ROCK inhibitors will become new molecular target drugs for vitreoretinal diseases. This review summarizes the recent progress on the mechanisms of action of ROCK and their applications in disease treatment.

SYSTEMIC RISK FACTORS IN BILATERAL PROLIFERATIVE DIABETIC RETINOPATHY REQUIRING VITRECTOMY

PURPOSE

The visual outcome after vitrectomy for proliferative diabetic retinopathy (PDR) is often poor. Bilateral vitrectomy has been especially associated with a poor visual prognosis in patients with PDR. The authors investigated the systemic risk factors for PDR requiring bilateral vitrectomy compared with unilateral vitrectomy.

METHODS

The authors retrospectively reviewed 86 consecutive patients with Type 2 diabetes mellitus with PDR who underwent vitrectomy. These patients were divided into 2 groups: bilateral vitrectomy within 1 year (n = 25) and unilateral vitrectomy (n = 61). The authors compared the systemic risk factors: age, sex, duration of diabetes, hemoglobin A1c, body mass index, estimated glomerular filtration rate, uric albumin, hypertension, dyslipidemia, history of ischemic heart disease, arteriosclerosis obliterans, and smoking.

RESULTS

There were significantly more cases with severe renal dysfunction in the bilateral vitrectomy group compared with the unilateral one (estimated glomerular filtration rate <30 mL/minute/1.73 m; bilateral cases = 5/25; unilateral cases = 2/61; P = 0.02).

CONCLUSION

The authors found that severe renal dysfunction may be a risk factor in PDR requiring bilateral vitrectomy, indicating that careful attention needs to be paid to prevent the progression of diabetic retinopathy to severe PDR in the other eye if patients have severe unilateral PDR and severe renal dysfunction.

Stakeholders’ perspectives on the management of diabetic retinopathy for a district health system – South Africa

Background: Clinical practice guidelines for the management of diabetic retinopathy (DR) adopted in various countries show variations in methods of examinations, screeners and classification systems. The South African National Guidelines for the frequency of referral of patients with diabetes mellitus (DM) for DR assessment were developed more than a decade ago. They do not specify the role of primary healthcare workers (PHCW) to manage DR at primary healthcare (PHC) level. The primary objective of this study was to establish the current role of PHCW in managing diabetic eye disease.Method: A cross-sectional study was conducted, and questionnaires were distributed to a total of 181 healthcare practitioners (HCPs) in public health institutions situated in the northern eThekwini district of KwaZulu-Natal. Clinics and community health centres (CHCs) were selected based on the assumption that PHC nurses, general practitioners or medical officers (MOs) and ophthalmic nurses practice at these institutions. The hospitals selected were the referral institutions for the selected clinics and CHCs. The questionnaires distributed included questions relating to the DR classification systems usage, HCP interaction and opinions on how HCPs could be valuable in managing DR.Results: Only two out of the five ophthalmic nurses were familiar with the grading classification systems for DR. Ophthalmic nurses had less interaction with general practitioners or MOs (40.0%) than the PHC nurses (60.0%). Only 2.4% of the PHC nurses interacted with ophthalmologists. Four of the five ophthalmic nurses indicated that PHC nurses would be valuable in the management of DR by taking visual acuity (VA) and conducting a pinhole test. More than 60% of the general practitioners or MOs (65.6%) suggested that ophthalmic nurses do a fundus examination. Ophthalmologists indicated that the PHC nurses were the least capable (17.7%) to screen for DR.Conclusion: Primary healthcare workers such as PHC nurses, ophthalmic nurses, general practitioners or MOs and optometrists have specific roles to play in DR management, which includes its prevention, detection, grading, referral and monitoring.

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.

Angiogenesis and Inflammation Crosstalk in Diabetic Retinopathy

Diabetic retinopathy (DR) is one of the most prevalent microvascular complications of diabetes and one of the most frequent causes of blindness in active age. Etiopathogenesis behind this important complication is related to several biochemical, hemodynamic and endocrine mechanisms with a preponderant initial role assumed by polyol pathways, increment of growth factors, accumulation of advanced glycation end products (AGE), activation of protein kinase C (PKC), activation of the renin-angiotensin-aldosterone system (RAAS), and leukostasis. Chronic and sustained hyperglycemia works as a trigger to the early alterations that culminate in vascular dysfunction. Hypoxia also plays an essential role in disease progression with promotion of neovascularization and vascular dystrophies with vitreous hemorrhages induction. Thus, the accumulation of fluids and protein exudates in ocular cavities leads to an opacity augmentation of the cornea that associated to neurodegeneration results in vision loss, being this a devastating characteristic of the disease final stage. During disease progression, inflammatory molecules are produced and angiogenesis occur. Furthermore, VEGF is overexpressed by the maintained hyperglycemic environment and up-regulated by tissue hypoxia. Also pro-inflammatory mediators regulated by cytokines, such as tumor necrosis factor (TNF-α) and interleukin-1 beta (IL-1β), and growth factors leads to the progression of these processes, culminating in vasopermeability (diabetes macular edema) and/or pathological angiogenesis (proliferative diabetic retinopathy). It was found a mutual contribution between inflammation and angiogenesis along the process. J. Cell. Biochem. 117: 2443-2453, 2016. © 2016 Wiley Periodicals, Inc.

Four-port bimanual 23-gauge vitrectomy for diabetic tractional retinal detachment

PURPOSE

Four-port bimanual vitrectomy is a surgical technique that facilitates removal of epiretinal membranes in severe proliferative diabetic retinopathy (PDR). As the illumination is held by the assistant through the fourth scleral incision, fibrovascular membranes are removed by bimanual manipulation techniques. The objective of this study was to evaluate the safety and efficacy of four-port bimanual 23-gauge vitrectomy for patients with tractional retinal detachment (TRD) in severe PDR.

DESIGN

Retrospective, comparative, consecutive, interventional case series.

METHODS

Sixty-six eyes of 58 consecutive patients who underwent primary vitrectomy for severe diabetic TRD. Thirty-six eyes of 31 cases that were treated with four-port 23-gauge vitrectomy were compared with 30 eyes of 27 cases that were treated with 23-gauge pars plana vitrectomy (PPV). Main outcome measures were best-corrected visual acuity (BCVA), retinal status, intraocular pressure, and incidence of intraoperative and postoperative complications with at least 6 months of follow-up.

RESULTS

The primary and ultimate anatomic success rates (94.4% versus 93.3%, and 100% in both groups, respectively) and the mean BCVA changes did not differ significantly between groups. The whole surgical time and the membrane removal time were significantly (p < 0.001, respectively) shorter in the four-port 23-gauge group than in the 23-gauge group. There was no difference in the incidence of intraoperative and postoperative complications in both groups.

CONCLUSIONS

Four-port bimanual 23-gauge vitrectomy offers comparable anatomic success and shortens the surgical time compared with conventional 23-gauge PPV in patients with TRD resulting from severe PDR.

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.

Segmentation and removal of fibrovascular membranes with high-speed 23 G transconjunctival sutureless vitrectomy, in severe proliferative diabetic retinopathy

Aim

To evaluate the effectiveness and safety of high-speed (5,000 cuts per minute) 23 G transconjunctival sutureless vitrectomy (TSV) in severe diabetic fibrovascular proliferation (DFVP).

Patients and methods

In this retrospective consecutive case series, patients who underwent 23 G TSV for severe DFVP between October 2011 and March 2014 at our institution were evaluated. 23 G TSV was performed with a high-speed (5,000 cuts per minute) cutter without a chandelier light.

Results

The mean follow-up period was 8 months (range: 4–23 months). Of the 27 eyes of 27 patients, 14 eyes (52%) underwent concomitant phacoemulsification with posterior chamber intraocular lens implantation, nine eyes (33%) were pseudophakic, and four eyes were phakic (15%). DFVP was removed with ease in all, and visual acuity was improved in 18 (67%) eyes. Iatrogenic retinal tear was observed in four eyes (15%) and treated successfully during surgery. Suture placement to a single sclerotomy was performed in eight eyes (30%). Postoperative intraocular hemorrhage was observed in five eyes (18%). Cataract formation was observed in two of the four phakic eyes. Three (11%) patients had postoperative intraocular pressure rise. Postoperative hypotony (≤6 mmHg) and endophthalmitis were not observed in any eye.

Conclusion

The segmentation and removal of fibrovascular membranes with high-speed 23 G TSV seems to be a safe and easy method in severe diabetic eye disease.

Characteristics, Demographics, Outcomes, and Complications of Diabetic Traction Retinal Detachments Treated with Silicone Oil Tamponade

Purpose

To describe the characteristics, demographics, anatomic and functional outcomes, and complications of diabetic eyes with traction retinal detachment (TRD) or combined traction/rhegmatogenous retinal detachment that underwent pars plana vitrectomy (PPV) silicone oil (SO) tamponade.

Methods

In this retrospective chart review, exclusion criteria included previous PPV.

Results

Forty eyes were identified. The mean preoperative complexity score (CS) of the TRDs was 5.95 (range 4-8). In patients with ≥6 months of follow-up (33; 82.5%), eyes with lower CSs had a better mean final visual acuity (VA): ~20/400 for CS 4, and hand motions (HM)-1/200 for CS >5. Eyes with macula-sparing TRDs had better final VA (~20/400) than those with a detached macula (~HM). Eyes with >3 panretinal photocoagulation sessions attained better mean final VA (20/400) than eyes without any history of laser treatment (~HM). The most frequent complications were cataract (46%), preretinal fibrosis (33%), recurrent TRD (15%), oil migration to the anterior chamber (12%), corneal edema (12%), and oil emulsification (9%). Eleven (27.5%) eyes underwent SO removal.

Conclusions

The average complexity score was high in this series. Use of SO tamponade for diabetic TRDs is not without complications, but may be beneficial in stabilizing vision in eyes with otherwise poor prognosis.

New Diagnostic and Therapeutic Approaches for Preventing the Progression of Diabetic Retinopathy

Diabetic retinopathy (DR) is a severe sight-threatening complication of diabetes mellitus. Retinal laser photocoagulation, antivascular endothelial growth factors, steroid therapy, and pars plana vitrectomy are now used extensively to treat advanced stages of diabetic retinopathy. Currently, diagnostic devices like ultrawide field fundus fluorescein angiography and the improvement of optical coherence tomography have provided quicker and more precise diagnosis of early diabetic retinopathy. Thus, treatment protocols have been modified accordingly. Various types of lasers, including the subthreshold micropulse laser and RPE-targeting laser, and selective targeted photocoagulation may be future alternatives to conventional retinal photocoagulation, with fewer complications. The new developed intravitreal medications and implants have provided more therapeutic options, with promising results.

Advantages of diabetic tractional retinal detachment repair

Purpose

To evaluate the outcomes and complications of patients with diabetic tractional retinal detachment (TRD) treated with pars plana vitrectomy (PPV).

Patients and methods

We retrospectively studied a case series of 24 eyes of 21 patients at a single tertiary, university-affiliated medical center. A review was carried out on patients who underwent PPV for the management of TRD due to proliferative diabetic retinopathy from October 2011 to November 2013. Preoperative and final visual outcomes, intraoperative and postoperative complications, and medical background were evaluated.

Results

A 23 G instrumentation was used in 23 eyes (95.8%), and a 25 G instrumentation in one (4.2%). Mean postoperative follow-up time was 13.3 months (4–30 months). Visual acuity significantly improved from logarithm of the minimum angle of resolution (LogMAR) 1.48 to LogMAR 1.05 (P<0.05). Visual acuity improved by ≥3 lines in 75% of patients. Intraoperative complications included iatrogenic retinal breaks in seven eyes (22.9%) and vitreal hemorrhage in nine eyes (37.5%). In two eyes, one sclerotomy was enlarged to 20 G (8.3%). Postoperative complications included reoperation in five eyes (20.8%) due to persistent subretinal fluid (n=3), vitreous hemorrhage (n=1), and dislocated intraocular lens (n=1). Thirteen patients (54.2%) had postoperative vitreous hemorrhage that cleared spontaneously, five patients (20.8%) required antiglaucoma medications for increased intraocular pressure, seven patients (29.2%) developed an epiretinal membrane, and two patients (8.3%) developed a macular hole.

Conclusion

Patients with diabetic TRD can benefit from PPV surgery. Intraoperative and postoperative complications can be attributed to the complexity of this disease.

Intra-silicone oil injection of methotrexate at the end of vitrectomy for advanced proliferative diabetic retinopathy

PURPOSE

To evaluate the role of methotrexate (MTX) injected into the silicone oil at the end of pars plana vitrectomy for advanced proliferative diabetic retinopathy (PDR).

METHODS

In this prospective comparative interventional study, eyes with severe diabetic tractional macular detachment or combined tractional/rhegmatogenous retinal detachment were included. Standard 20 gauge pars plana vitrectomy, and retinal reattachment was performed. In the case group, 250 μg MTX was injected into the silicone oil at the end of surgery. The rate of retinal re-detachment associated with fibrovascular proliferation or proliferative vitreoretinopathy (PVR) was assessed.

RESULTS

Overall, 38 eyes of 35 patients (19 cases and 19 controls) were studied. The two groups were matched for age, sex, preoperative visual acuity, and the type of surgery (vitrectomy alone vs combined phacoemulsification/vitrectomy). Retinal re-detachment with fibrovascular proliferation or PVR occurred in seven eyes (36.8%) in the MTX group and eight eyes (42.1%) in the control group (P = 0.74). Mean change in visual acuity was 0.04 ± 0.71 and 0.39 ± 0.70 logMAR in the MTX and the control group, respectively (P = 0.14). The rate of improvement or worsening of visual acuity was similar between the two groups (P = 0.51 and P = 0.12).

CONCLUSION

Intra-silicone injection of MTX at the end of vitrectomy for retinal detachment associated with severe PDR did not reduce the risk of postoperative retinal detachment due to the fibrous or fibrovascular proliferations.