Surgical management of diabetic retinopathy

Beacon of Hope for Age-Related Retinopathy: Antioxidative Mechanisms and Pre-Clinical Trials of Quercetin Therapy

Age-related retinopathy is one of the leading causes of visual impairment and irreversible blindness, characterized by progressive neuronal and myelin loss. The damages caused by oxidation contributes to the hallmarks of aging and represents fundamental components in pathological pathways that are thought to drive multiple age-related retinopathies. Quercetin (Que), a natural polyphenol abundant in vegetables, herbs, and fruits, has been extensively studied for its long-term antioxidative effects mediated through diverse mechanisms. Additionally, Que and its derivatives exhibit a broad spectrum of pharmacological characteristics in the cellular responses of age-related retinopathy induced by oxidative stress, including anti-inflammatory, anti-neovascularization, regulatory, and neuroprotective effects in autophagy and apoptosis processes. This review mainly focuses on the antioxidative mechanisms and curative effects of Que treatment for various age-related retinopathies, such as retinitis pigmentosa, diabetic retinopathy, age-related macular degeneration, and glaucoma. Furthermore, we discuss emerging technologies and methods involving Que and its derivatives in the therapeutic strategies for age-related retinopathies, highlighting their promise for clinical translation.

Revolutionizing drug delivery strategies with probucol to combat oxidative stress in retinal degeneration: A comprehensive review

Localized oxidative stress plays a key role in the development of retinal degenerative diseases, with diabetic retinopathy (DR) being one of them, contributing significantly to this vision-threatening complication of diabetes. Increased oxidative burden leads to dysfunction across various retinal cell types, including vascular endothelial cells, neurons, glial cells and pericytes. Importantly, even after achieving normalized glycemia, the detrimental effects of oxidative stress persist. Nonetheless, growing data highlights the therapeutic potential of antioxidants in safeguarding vision. However, extensive clinical trials using traditional antioxidants have produced mixed results. Therefore, probucol, known for its ability to limit vascular oxidative stress, decrease superoxide generation, and improve endogenous antioxidant activity, is a promising candidate explored in this review. In addition to describing probucol, this review will explore novel therapeutic formulation strategies by incorporating bile acid into probucol-loaded nanoparticles to enhance drug delivery to the posterior segment of the eye for more effective management of DR. The integration of bio-nanotechnology with probucol and bile acids represents a promising avenue for developing effective therapies for DR, addressing the limitations of traditional antioxidant treatments.

A look to the future: cyclodextrins and cyclodextrin-based drug delivery to the retina

INTRODUCTION

Retinal diseases are a leading cause of vision loss, affecting millions of people worldwide. Current treatment options are based on invasive methods such as intravitreal injections. Therefore, there is a need for alternative therapeutic strategies that are both effective and more patient-friendly.

AREAS COVERED

Topical drug delivery has gained attention as a preferred noninvasive approach, although it is hindered by several ocular barriers. Cyclodextrin (CD)-based nanoparticles have emerged as a promising strategy to overcome these limitations by enhancing drug permeability in the posterior segment of the eye. This review discusses the potential of CDs as enabling pharmaceutical excipients, their role in improving ocular drug bioavailability, and provides examples of CD-based eye drop formulations currently under development or undergoing clinical trials. Also, the role of CDs as active pharmaceutical agents in ophthalmology is discussed.

EXPERT OPINION

CD-based nanoparticle eye drops present a promising solution and have shown clinical success. CDs are approved pharmaceutical excipients for eye drop formulations and can act as active pharmaceutical ingredients for the treatment of inherent retinal diseases. Future innovations in hybrid CD-based delivery systems and integration of novel therapeutic compounds could provide more efficient and targeted treatment options for retinal diseases.

Elucidating postoperative dynamics in tractional retinal detachment: a systematic review and meta-analysis of structural and functional outcomes following diabetic vitrectomy, including an analysis of postoperative complications

This meta-analysis aims to evaluate the efficacy and safety of diabetic vitrectomy for treating tractional retinal detachment (TRD) by assessing visual acuity improvements, retinal reattachment success rates, and the frequency of postoperative complications. A comprehensive literature search identified 1,211 studies, 30 of which met the inclusion criteria and were analyzed. The meta-analyses were conducted via random effects models to account for heterogeneity. The primary outcomes were visual acuity improvement and retinal reattachment success, whereas postoperative complications were analyzed as secondary outcomes. Funnel plots, trim-and-fill methods, and Egger's regression tests were employed to assess and adjust for publication bias. The meta-analysis included data from 1,844 eyes across 30 studies. The pooled mean difference (MD) in visual acuity following diabetic vitrectomy was 0.80 logMAR (95% CI: 0.58-1.01, p < 0.0001), with significant heterogeneity (I² = 95%). The trim-and-fill method adjusted the MD to 1.15 (95% CI: 0.85-1.45), indicating potential publication bias. The pooled proportion of retinal reattachment success was 94.63% (95% CI: 90.88-96.89%), with substantial heterogeneity (I² = 82.2%). Egger's regression test confirmed publication bias in the retinal reattachment data (t = 6.07, df = 25, p < 0.0001). The most common postoperative complications were vitreous hemorrhage (8.2%, 0-41%), elevated intraocular pressure (7.3%, 0-25%), and cataract formation (10.3%, 0-43%). Diabetic vitrectomy significantly improves visual acuity and achieves high retinal reattachment success rates in patients with TRD despite considerable heterogeneity across studies. However, a critical limitation of the current literature is the lack of comprehensive reporting of essential markers of perfusion, such as the choroidal vascularity index and choriocapillaris flow area, which are crucial for a thorough understanding of the impact of vitrectomy on ocular perfusion and its correlation with structural and functional outcomes. These findings also highlight the need for vigilant postoperative management to mitigate common complications. Adjustments for publication bias via the trim-and-fill method suggest that the initial estimates of efficacy may be optimistic, but the overall benefits of the procedure remain substantial. Further research is warranted to standardize surgical techniques, include detailed perfusion outcomes, and enhance the reliability of future meta-analyses. Trial registration: Retrospectively registered.

Pharmacological adjuvants for diabetic vitrectomy surgery

Diabetic vitrectomy is a highly intricate surgical procedure performed during the advanced stages of diabetic retinopathy (DR). It is used to treat conditions such as tractional or combined retinal detachment, vitreous hemorrhage, and subhyaloid hemorrhage, which are all severe manifestations of proliferative DR. The results of the surgery are uncertain and variable. Vitreoretinal surgery has made significant progress since the early stages of vitrectomy. In the past ten years, advancements in intravitreal pharmacotherapy have emerged, offering new possibilities to improve the surgical results for our patients. Within the realm of medical terminology, an "adjunct" refers to a pharmaceutical or substance employed to aid or expedite the primary therapeutic intervention for a particular ailment. Their introduction has broadened the range of therapeutic choices that are accessible prior to, during, and following surgical procedures. This review article will specifically analyze the pharmacological adjuncts used in diabetic vitrectomy surgery, with a focus on their role in facilitating or aiding specific steps of the procedure. The implementation of this system of categorization offers benefits to the surgeon by allowing them to foresee potential difficulties that may occur during the surgical procedure and to choose the appropriate pharmacological agent to effectively tackle these challenges, thus enhancing surgical success rates.

Advanced drug delivery strategies for diabetic retinopathy: current therapeutic advancement, and delivery methods overcoming barriers, and experimental modalities

INTRODUCTION

Diabetic retinopathy, a significant trigger for blindness among working age individuals with diabetes, poses a substantial global health challenge. Understanding its underlying mechanisms is pivotal for developing effective treatments. Current treatment options, such as anti-VEGF agents, corticosteroids, laser photocoagulation, and vitreous surgery, have their limitations, prompting the exploration of innovative approaches like nanocapsules based drug-delivery systems. Nanoparticles provide promising solutions to improve drug delivery in ocular medicine, overcoming the complexities of ocular anatomy and existing treatment constraints.

AREAS COVERED

This review explored advanced therapeutic strategies for diabetic retinopathy, focusing on current medications with their limitations, drug delivery methods, device innovations, and overcoming associated barriers. Through comprehensive review, it aimed to contribute to the discovery of more efficient management strategies for diabetic retinopathy in the future.

EXPERT OPINION

In the next five to ten years, we expect a revolutionary shift in how diabetic retinopathy is treated. As we deepen our understanding of oxidative stress and metabolic dysfunction, antioxidants with specialised delivery matrices are poised to take center stage in prevention and treatment strategies. Our vision is to create a more integrated approach to diabetic retinopathy management that not only improves patient outcomes but also reduces the risks associated to traditional therapies.

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.

Effectiveness of Suprachoroidal Injection of Triamcinolone Acetonide in Diabetic Macular Edema Following Pars Plana Vitrectomy Using a Modified Custom Microneedle

Purpose

The present study evaluated the efficacy of suprachoroidal injection of Triamcinolone Acetonide (SCTA) in diabetic macular edema (DME) following pars plana vitrectomy (PPV) using a modified microneedle.

Patients and methods

A prospective interventional study was conducted on 60 eyes of 60 patients with centrally involved diabetic macular edema following pars plana vitrectomy (PPV). SCTA was performed at the baseline and repeated after 3 months in case of persistent subretinal or intraretinal fluid, central macular thickness (CMT) more than 300 µm or visual loss by more than one line of the Snellen chart.

Results

The present study detected significant reduction of the CMT from 498.3 ± 94.8 µm at the baseline to 212.3 ± 11.9 µm after 12 months of injection with p < 0.001 and a significant improvement of best corrected visual acuity (BCVA) from 1 (0.9-1.2) at the baseline to 0.5 (0.3-0.7) after 12 months of injection with p < 0.001. The intraocular pressure (IOP) increased significantly after 3 months of injection with p < 0.001 and then gradually declined to its normal level after 6 months. Inner segment/outer segment (IS/OS) disruption was the only significant predictor of the final CMT; however, the number of injections, IS/OS disruption, baseline BCVA and the HbA1C level were the significant predictors of the final BCVA after injection.

Conclusion

Suprachoroidal injection of TA using this microneedle resulted in significant anatomical and functional improvement in previously vitrectomized diabetic macular edema patients with no recorded ocular or systemic adverse events.

27‑Gauge vitrectomy vs. 25‑gauge vitrectomy in the management of proliferative diabetic retinopathy with preoperative intravitreal injection of conbercept

Small-gauge vitrectomy has become popular due to its notable advantages, including less trauma, shortened convalescence and improved manoeuvrability. The aim of the present study was to compare the surgical outcomes of 27-gauge (27-G) vitrectomy with those of 25-gauge (25-G) vitrectomy in the management of proliferative diabetic retinopathy (PDR) with preoperative intravitreal injection of conbercept. The data of 48 consecutive patients with PDR (48 eyes) were retrospectively collected. The patients underwent conbercept intravitreal injection and pars plana vitrectomy with a 27-G group (23 eyes) or 25-G group (25 eyes) vitrectomy system. The operating time, suturing rate, endodiathermy rate, postoperative best-corrected visual acuity (BCVA), intraocular pressure (IOP) and complications were recorded. The mean postoperative BCVA at final follow-up was significantly improved compared with that at the baseline in both groups (P<0.001 for both). The differences in the mean BCVA changes between the two groups were not significant (P>0.99), and no differences were observed in the final central foveal thickness (P=0.51) between the two groups. The final IOP remained stable compared with that at the baseline in the 27-G group (P=0.36) and the 25-G group (P=0.05). The suturing rate was significantly decreased in the 27-G group compared with the 25-G group (P=0.04). There were no significant differences between the two groups in terms of the operating time (P=0.18), rate of endodiathermy use (P>0.99), iatrogenic retinal breaks (P=0.42) or postoperative recurrent vitreous haemorrhage (P>0.99). In addition, no case of ocular hypotony was observed in either group. In conclusion, 27-G vitrectomy was as efficient and safe as 25-G vitrectomy in the management of PDR in terms of operating time and complications. With reference to the literature, preoperative conbercept injection appears to assist in decreasing the incidence of intraoperative and postoperative complications.

[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.

Visual outcomes and prognostic factors following 23G vitrectomy for vitreous hemorrhage in eyes with proliferative diabetic retinopathy

PURPOSE

We aimed to evaluate the factors influencing the visual gain following pars plana vitrectomy for vitreous hemorrhage in patients with proliferative diabetic retinopathy.

METHODS

A retrospective study was conducted on 172 eyes of 143 consecutive patients with diabetes mellitus between January 2012 and January 2018. Demographic data, ophthalmological findings, surgery details, and visual outcomes were gathered after consulting the patients' records. The main outcome measured was the improvement of best corrected visual acuity and the secondary outcomes measured were rebleeding and complications.

RESULTS

Best corrected visual acuity improved in 103 eyes (59.88%), worsened in 45 eyes (26.16%), and remained unchanged in 24 eyes (13.95%). Type 2 diabetes mellitus was significantly associated with better final best corrected visual acuity (p=0.0244). Previous treatment by pan-retinal laser photocoagulation or intravitreal bevacizumab determined better final best corrected visual acuity, but not significantly (p>0.05). Preoperative rubeosis iridis and neovascular glaucoma did not influence the outcomes. The lack of fibrovascular proliferation requiring dissection was a significant factor for better final best corrected visual acuity (p=0.0006). Rebleeding occurred in 37.1% of the eyes and it was not influenced by the antiplatelet drugs (p>0.05). Postoperative neovascular glaucoma was a negative prognostic factor (p=0.0037).

CONCLUSION

The final best corrected visual acuity was influenced positively by type 2 diabetes mellitus and the absence of preoperative extensive fibrovascular proliferation and negatively by postoperative neovascular glaucoma.

Post-vitrectomy delayed retinal breaks in proliferative diabetic retinopathy

PURPOSE

To report a series of cases of post-operative new secondary retinal breaks following vitrectomy for proliferative diabetic retinopathy (PDR).

METHODS

This retrospective case series included data of patients diagnosed with post-operative retinal breaks following uneventful vitrectomy surgery for PDR from January 2018 to December 2021.

RESULTS

New post-vitrectomy retinal breaks in PDR were seen in 7% of eyes (n = 10/148 eyes; 10 patients). Age of study patients ranged from 45 to 69 years and there were 8 males. Vitreous surgery was performed for vitreous hemorrhage in six eyes, macular tractional retinal detachment in three eyes and epiretinal membrane in one eye. Tractional fibrovascular proliferation near the retinal break prior to its development was noted either pre- or intra-operatively in 8 eyes. Mean time interval between the vitreous surgery and secondary retinal break development was 6.4 months. Residual fibrous tissue post-surgery adjacent to the break was noted in 4 cases. Sclerosed retinal vessel was noted in 4 eyes and associated inner retinal thinning or schisis in 5 eyes. No retinal detachment was noted in any case. Prophylactic barrage was done in 4 eyes. Last follow-up interval ranged from 4 to 53 months and visual acuity ranged from 6/6 to 6/60. No subretinal fluid, traction or break enlargement was noted at the last visit.

CONCLUSION

Delayed post-operative retinal breaks following vitrectomy are uncommon in PDR eyes. Careful preoperative evaluation of the retinal proliferations, intraoperative dissection of the membranes and regular post-operative reviews are vital in anticipating the development of delayed post-vitrectomy retinal breaks. Observation could be the management strategy for these breaks.

Subfoveal choroidal thickness following pars plana vitrectomy in tractional diabetic macular edema

Purpose

To evaluate changes in subfoveal choroidal thickness (SCT) in cases of tractional diabetic macular edema (DME) after pars plana vitrectomy (PPV).

Methods

This prospective study included 31 eyes of 31 patients who underwent PPV for the management of tractional DME. Best-corrected visual acuity (BCVA), SCT, and central macular thickness (CMT) were measured before the operation, as well as one, three, and six months following the surgery in the operated eyes and at baseline, as well as six months in the fellow eyes.

Results

The SCT decline in eyes with tractional DME was statistically significant six months postoperatively (P = 0.009). A statistically significant decline was observed in the CMT values one, three, and six months postoperatively in eyes with tractional DME (P = 0.02, P < 0.001, and P < 0.001, respectively). There was a statistically significant improvement in the visual acuity of the affected eyes three (P = 0.047) and six months (P = 0.017) postoperatively.

Conclusion

After PPV for the treatment of tractional DME, a statistically significant decrease in the CMT values is detectable from the first month after surgery, followed by the improvement of BCVA from the third month. It is worth mentioning that a decrease was found in the SCT six months postoperatively.

Pars plana vitrectomy for tractional diabetic macular edema with or without internal limiting membrane peeling

Background

The effectiveness of internal limiting membrane (ILM) peeling in the surgical treatment of tractional diabetic macular edema (DME), although widely examined, remains controversial. This study aimed to assess the efficacy of pars plana vitrectomy (PPV) in the management of tractional DME and to highlight any benefits of additional ILM peeling.

Methods

This was an open-label, prospective, comparative, and interventional study that enrolled 50 eyes with tractional DME that underwent PPV and allocated each to one of two groups: group A consisted of 25 eyes that had no ILM peeling and group B consisted of 25 eyes that underwent ILM peeling. Postoperative assessments of best-corrected distance visual acuity (BCDVA) in the logarithm of minimal angle of resolution (logMAR) notation and central macular thickness (CMT) were performed at 1, 3, and 6 months postoperatively.

Results

At baseline, the two groups were comparable in terms of sex ratios, phakic status, insulin use, coexistence of hypertension, and mean (standard deviation [SD]) age, BCDVA, CMT, duration of diabetes mellitus, and glycosylated hemoglobin (HbA1c) levels. In group A, the mean (SD) BCDVA improved significantly from 0.89 (0.12) logMAR preoperatively to 0.64 (0.24) logMAR (P < 0.001), and the mean (SD) CMT declined significantly from 471.28 (80.83) µm to 228.20 (26.45) µm (P < 0.001), at the 6-month postoperative assessment. Likewise, in group B, the mean (SD) BCDVA improved significantly from 0.83 (0.10) logMAR preoperatively to 0.58 (0.24) logMAR (P < 0.001), and the mean (SD) CMT decreased significantly from 496.84 (89.82) µm to 226.20 (18.04) µm (P < 0.001), after 6 months. There were no significant differences between groups A and B in the changes in BCDVA (Delta BCDVA) or CMT (Delta CMT) at 1, 3, and 6 months postoperatively with respect to the baseline values (all P > 0.05). Postoperative complications were comparable between the two groups. A significant negative correlation was detected between the preoperative HbA1c level and BCDVA improvement in all participants (r = - 0.82; P < 0.001).

Conclusions

PPV is an effective treatment for tractional DME. Additional ILM peeling was not significantly associated with functional and anatomical benefits over a short period. Long-term glycemic control plays a role in vision gain after vitrectomy in patients with diabetes. Further long-term studies are required to verify our findings.

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.

Suprachoroidal injection of triamcinolone acetonide using a custom-made needle to treat diabetic macular edema post pars plana vitrectomy: a case series

Objective

Diabetic macular edema (DME), the most common cause of diabetes-related visual impairment, may occur following pars plana vitrectomy (PPV) to manage proliferative diabetic retinopathy complications. This retrospective single-centre case series evaluated the efficacy and safety of injecting 4 mg/0.1 ml triamcinolone into the suprachoroidal space using a custom-made needle to treat DME post PPV.

Methods

Data regarding central macular thickness (CMT) using spectral domain-optical coherence tomography and best-corrected visual acuity (by Snellen chart) at baseline (pre-injection), and at 1, 4, and 8 weeks following injection were analysed, along with intraocular pressure (IOP), cataract progression, and ocular safety.

Results

Eleven eyes in 10 patients received 11 suprachoroidal injections. Vision improvement was noted (0.75 log minimum angle of resolution (MAR) at baseline to 0.40 log MAR after treatment). CMT reduced significantly from 456.45 ± 113.42 μm at baseline to 247.63 ± 53.40 μm at 8 weeks following injection. No rise in IOP, or cataract development in the single treated phakic eye, was observed during 8 weeks of follow-up.

Conclusion

Suprachoroidal injection of triamcinolone using a custom-made needle to treat DME post PPV shows promising results with acceptable safety outcomes. Large clinical trials with longer follow-up are needed to evaluate this treatment option for countries with limited health-care resources.

Vitreoretinal Society of India practice pattern survey 2020: Surgical retina

Purpose:

To present the outcomes of the Vitreo-retinal Society of India (VRSI) Practice Pattern Survey 2020 in surgical retina.

Methods:

An online survey of members of VRSI was conducted in April 2020 regarding their practice patterns on varied medical and surgical retina topics concerning imaging and management approach. The results were evaluated by two independent experts in this field and compared with the evidence and other practice patterns in the world.

Results:

A total of 107 VRSI members participated in the online survey. Responses were obtained on management of wide-ranging surgical retina topics such as diabetic retinopathy, retinal detachments, Macular Hole, and Epiretinal membranes. Participants were also surveyed regarding their attitudes and perceptions about microscopes with the heads-up display system. Each of the survey question responses were then compared to contemporary literature, including evidence-based guidelines, randomized controlled trials, real-world evidence, and analogous international surveys. Comprehensive analysis related to this has been put forward in the article.

Conclusion:

This survey represents the contemporary practice patterns among vitreoretinal specialists in India. The survey results are vital for fellow practitioners to understand the “standard of care” practice in surgical retina. This will guide them to devise the best possible individualized treatment strategy for most favorable clinical outcomes.

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.

Changes in the Density of Corneal Endothelial Cells in Elderly Diabetic Patients After Combined Phacovitrectomy and Ex-PRESS Glaucoma Implants

BACKGROUND & OBJECTIVE

Corneal endothelial cells (ECD) are characterized by limited regenerative potential, which is additionally impaired in patients with diabetes. This retrospective study included 27 patients aged 58.1±13.6, 16 female and 11 males, who underwent 23-gauge vitrectomy in combination with cataract surgery (phacovitrectomy) and further Ex-PRESS shunt implantation throughout 2013-2017 at St. Barbara Hospital in Sosnowiec, Poland.

METHODS

In our study, we distinguished 4 periods: initial period; post phacovitrectomy and removal of oil tamponade; and 3 and 12 months post implantation of the Ex-PRESS shunt. Statistical analysis was performed at the level of statistical significance of p<0.05. It included an analysis of variance (ANOVA) and Tukey's post-hoc test in order to determine the differences in the density of ECD cells/mm2 between the periods of observation. The paired-samples t-Student test was also performed to determine whether the differences in visual acuity values before and after PPV and before and after Ex-PRESS shunt were statistically significant.

RESULTS

The initial count of ECD cells was 2381.1±249, which decreased to 1872.8±350.7 cell/mm2 and finally to 1677.9±327 at the endpoint. Differences in the density of ECD cells/mm2 were observed to be statistically significant between the periods: after PPV vs. initial number of ECD (p = 0.000138); before 3 months after Ex-PRESS shunt vs. initial number of ECD (p = 0.000138); 12 months after Ex- PRESS shunt vs. initial number of ECD (p = 0000138). Analyzing the changes in visual acuity, we observed a deterioration both before and 3 months after Ex-PRESS shunt (p = 0.007944) and before and after PPV (p = 0.060334). In turn, correlation analysis indicated that there is a statistically significant, moderate, positive relationship. The relationship between visual acuity after Ex-PRESS shunt and ECD cells/mm2 density turned out to be statistically significant (r = +0.521381; p < 0.05).

CONCLUSION

Regardless of the period of observation and the choice of ophthalmic treatment of diabetic complications, we observed a decrease in the number of ECD cells and a deterioration in visual acuity. It is, therefore, reasonable to provide the patient with complete information about the proposed procedures and to consider the risk-benefit balance.

Effectiveness of Intravitreal Dexamethasone Implant Treatment for Diabetic Macular Edema in Vitrectomized Eyes

Objectives:

To report the effectiveness and long-term outcomes of intravitreal dexamethasone implantation for diabetic macular edema (DME) in vitrectomized eyes

Materials and Methods:

Medical records of patients were retrospectively reviewed. Time of pars plana vitrectomy (PPV), PPV indications, interval between DEX injection and PPV, other intravitreal treatment prior to DEX application, best corrected visual acuity (BCVA), intraocular pressure (IOP), and central retinal thickness (CRT) measured by optical coherence tomography were recorded.

Results:

Seventeen eyes of 17 patients were included in the study. The mean follow-up after DEX injection was 21±2.4 months (12-43 months). The female/male ratio was 11/6. Mean age was 60.7 years (46-70 years). Sixteen eyes (94.1%) were pseudophakic at the time of DEX treatment. The most common indication for PPV was tractional retinal detachment (8 eyes, 47.1%). Ten eyes (58.8%) received a single injection and a total of 30 DEX implantations were performed. Mean BCVA was 0.77 logarithm of the minimum angle of resolution (logMAR) units before the first injection and improved to 0.64, 0.68 and 0.66 logMAR after 1, 3 and 6 months, respectively (p<0.01). CRT decreased significantly from 452 µm at baseline to 310, 368±34 and 375 µm after 1, 3 and 6 months, respectively (p<0.04). Mean IOP was 16±1.2 mmHg at baseline and 18.2, 18.8 and 18.5 mmHg after 1, 3, and 6 months (p>0.05). Two eyes (%8) received topical anti-glaucoma medication (IOP≥25 mmHg). Similar results were observed in eyes receiving repeated DEX injections.

Conclusion:

Intravitreal DEX injection treatment seems to be effective for improving BCVA and decreasing CRT in vitrectomized eyes with DME. This effect seemed to last for 6 months in most eyes, but maximized at 3 months. Patients with repeated injections often require injection before 6 months.

[Possibilities of multicolor confocal scanning laser ophthalmoscopy in complex diagnostics of severe proliferative diabetic retinopathy]

Multicolor scanning laser ophthalmoscopy (multicolor SLO) is a new informative method of eye fundus visualization. The method is based on synchronously obtaining three separate confocal images with monochromatic laser sources - blue (488 nm), green (515 nm) and infrared (820 nm), which are then combined into one in the Multicolor mode.

PURPOSE

To evaluate the informative value of multicolor SLO in a complex examination of patients with severe proliferative diabetic retinopathy (PDR).

MATERIAL AND METHODS

A total of 46 patients (62 eyes) aged 19 to 75 years with severe PDR was examined. All patients had massive growth of proliferative tissue on the eye fundus, which caused traction deformation and/or retinal detachment in the posterior pole. Optical mediums of the eyes were sufficiently transparent to obtain high quality images. All patients underwent color photo-registration of the fundus, fluorescein angiography (FA), optical coherence tomography (OCT) and multicolor SLO under drug-induced mydriasis.

RESULTS

Pseudo-volumetric images obtained with multicolor SLO allow visualization of of preretinal proliferative membranes and their structure, the degree of their vascularization, the anatomical features of their attachment to retina, and the occluded vessels on fundus periphery. Being an additional option on scanning laser ophthalmoscope, the technique does not require special equipment, which enables several separate examinations, including OCT and FA, to be performed on a single device.

CONCLUSION

Multicolor SLO is a promising new method of visualizing structures of the eye fundus and can be successfully used in complex diagnostics, monitoring and preoperative preparation of patients with severe PDR.

Visual outcomes following vitrectomy for diabetic retinopathy amongst Indigenous and non-Indigenous Australians in South Australia and the Northern Territory

IMPORTANCE

Visual outcomes following diabetic vitrectomy have not previously been studied in an Australian population.

BACKGROUND

This analysis aimed to determine the rate of, and factors associated with visual success following diabetic vitrectomy performed for Indigenous and non-Indigenous Australians, and investigate factors predisposing to early progression to diabetic retinopathy (DR) requiring vitrectomy.

DESIGN

Retrospective, population-based audit.

PARTICIPANTS

All patients undergoing vitrectomy for the complications of DR in South Australia (SA) and the Northern Territory (NT) between 2007 and 2011.

METHODS

Medical records were audited and data collected, including demographics, diabetic history, past treatment for DR, indication for vitrectomy and visual acuity pre and postoperatively.

MAIN OUTCOME MEASURES

Visual success (gain of ≥15 ETDRS letters) at 6 and 12 months, postoperatively.

RESULTS

A total of 495 diabetic vitrectomies, for 404 eyes of 335 patients were performed in SA and NT between 2007 and 2011. 77 (23%) patients requiring diabetic vitrectomy were Indigenous Australians. 87% of patients undergoing diabetic vitrectomy had stable or improved vision at 1 year, postoperatively. There was no significant difference between indigenous and non-indigenous eyes achieving visual success (P = 0.929). Timely preoperative laser treatment (P = 0.03) and preoperative visual acuity (P = 0.01) were the predominant factors associated with visual success.

CONCLUSIONS AND RELEVANCE

Indigenous patients are just as likely to have improved vision following diabetic vitrectomy as non-Indigenous Australians. However, the small subset of indigenous patients with blind eyes prior to vitrectomy are significantly less likely to improve from surgery. The underlying factors associated with poor outcomes in this group requires further exploration.

Evaluation of EX-PRESS glaucoma implant in elderly diabetic patients after 23G vitrectomy

PURPOSE

The most frequent qualifications for pars plana vitrectomy (PPV) in diabetic patients include recurrent hemorrhage into the vitreous body chamber and vitreoretinal proliferation, also with traction retinal detachment. The aim of this study was to evaluate the effectiveness of EX-PRESS implant for the treatment of secondary glaucoma in elderly diabetic patients following PPV 23G with silicon oil or SF6 gas endotamponade.

MATERIALS AND METHODS

This retrospective analysis comprised 18 patients (19 eyes). We applied EX-PRESS implants in 9 patients with neovascular glaucoma (NVG) and in 10 patients with non-NVG. All patients had earlier history of diabetes and vitrectomy 23G for diabetic complications. Intraocular pressure (IOP) was measured and compared before; 7 days; 1, 3, 6, and 12 months; and a year after the surgery.

RESULTS

Application of the implant exhibited a lowering effect on IOP. After 1 month, 53% of patients had IOP values beyond 22 mmHg, while 86% after 1 year.

CONCLUSION

The implant can be used to treat both NVG and non-NVG in diabetic patients following PPV.

Inhibition of proliferation of retinal vascular endothelial cells more effectively than choroidal vascular endothelial cell proliferation by bevacizumab

AIM

To evaluate the differential inhibitory effects of bevacizumab on cell proliferation of vascular endothelial growth factor (VEGF)-stimulated choroidal vascular endothelial cells (CVECs) and retinal vascular endothelial cells (RVECs) in vitro.

METHODS

VEGF (400 ng/mL) enriched CVECs and RVECs were treated with escalating doses of bevacizumab (0.1, 0.5, 1, 1.5 and 2 mg/mL). Cell proliferation changes were analyzed with WST-1 assay and trypan blue exclusion assay at 48, 72h and 1wk. Morphological changes were recorded with bright field microscopy.

RESULTS

VEGF enriched RVECs showed significantly more decline of cell viability than CVECs after bevacizumab treatment. One week after treatment, RVEC cell proliferation decreased by 29.7%, 37.5%, 52.8%, 35.9% and 45.6% at 0.1, 0.5, 1.0, 1.5 and 2 mg/mL bevacizumab respectively compared to CVEC proliferation decrease of 4.1%, 7.7%, 2.4%, 4.1% and 17.7% (P<0.05) by WST-1 assay. Trypan blue exclusion assay also revealed similar decrease in RVEC proliferation of 20%, 60%, 73.3%, 80% and 93.3% compared to CVEC proliferation decrease of 4%, 12%, 22.9%, 16.7% and 22.2% respectively (P<0.05). The maximum differential effect between the two cell types was observed at bevacizumab doses of 1.0 and 1.5 mg/mL at all time points. RVECs were 22 fold more sensitive (P<0.01) compared to CVECs (52.8% vs 2.4%) at concentration of 1.0 mg/mL, and 8.7 fold more at 1.5 mg/mL (35.9% vs 4.1%) 1wk after treatment (P<0.05 respectively).

CONCLUSION

VEGF-enriched RVECs are more susceptible to bevacizumab inhibition than CVECs at clinically used dosage of 1.25 mg and this differential sensitivity between two cell types should be taken into consideration in dosage selection.

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.

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.

Three-Dimensional Enhanced Imaging of Vitreoretinal Interface in Diabetic Retinopathy Using Swept-Source Optical Coherence Tomography

PURPOSE

To analyze the vitreoretinal interface in diabetic eyes using 3-dimensional wide-field volumes acquired using high-speed, long-wavelength swept-source optical coherence tomography (SSOCT).

DESIGN

Prospective cross-sectional study.

METHODS

Fifty-six diabetic patients (88 eyes) and 11 healthy nondiabetic controls (22 eyes) were recruited. Up to 8 SSOCT volumes were acquired for each eye. A registration algorithm removed motion artifacts and merged multiple SSOCT volumes to improve signal. Vitreous visualization was enhanced using vitreous windowing method.

RESULTS

Of 88 diabetic eyes, 20 eyes had no retinopathy, 21 eyes had nonproliferative diabetic retinopathy (NPDR) without macular edema, 20 eyes had proliferative diabetic retinopathy (PDR) without macular edema, and 27 eyes had diabetic macular edema (DME) with either NPDR or PDR. Thick posterior hyaloid relative to healthy nondiabetic controls was observed in 0 of 20 (0%) diabetic eyes without retinopathy, 4 of 21 (19%) eyes with NPDR, 11 of 20 (55%) eyes with PDR, and 11 of 27 (41%) eyes with DME (P = .0001). Vitreoschisis was observed in 6 of 22 (27%) healthy nondiabetic eyes, 9 of 20 (45%) diabetic eyes without retinopathy, 10 of 21 (48%) eyes with NPDR, 13 of 20 (65%) eyes with PDR, and 17 of 27 (63%) eyes with DME (P = .007). While no healthy nondiabetic controls and diabetic eyes without retinopathy had adhesions/pegs between detached posterior hyaloid and retina, 1 of 21 (4%), 11 of 20 (55%), and 11 of 27 (41%) eyes with NPDR, PDR, and DME, respectively, demonstrated this feature (P = .0001).

CONCLUSION

SSOCT with motion-correction and vitreous windowing provides wide-field 3-dimensional information of vitreoretinal interface in diabetic eyes. This may be useful in assessing progression of retinopathy, planning diabetic vitreous surgery, and predicting treatment outcomes.

A prospective study on postoperative discomfort after 20-gauge pars plana vitrectomy

Purpose

To evaluate postoperative pain and other irritation symptoms after 20-gauge (20G) pars plana vitrectomy.

Materials and methods

A total of 110 consecutive patients were enrolled in our studies, and 87 patients who underwent the conventional 20G pars plana vitrectomy were included in the final analysis. All vitrectomies were performed using the same surgical technique by the same surgeon. Patients were examined before surgery and 1 day, 3 days, 7 days, 1 month, and 2 months postoperatively. The main outcome measures include patient age and sex, intraocular pressure (IOP), ocular pain, pain score, pain medication use, and other irritation symptoms comprising itching, foreign body sensation, burning, photophobia, and dryness. The pain was evaluated using the Numerical Rating Scale scored from 0 to 10.

Results

Postoperative pain was relatively common during the first day after surgery, as it was reported by 43 (49.4%) patients. Then, the prevalence gradually decreased to eleven (12.6%) patients at 2 months. Most patients reported mild or moderate pain, with a pain score of 1–5, but only four patients were given analgesics for ocular pain. A postoperative rise of IOP was noted in 25 patients at day 1. Most of these patients with high IOP reported moderate pain. Other ocular irritation symptoms were varied after surgery. There was still one-quarter of patients that had foreign body sensation and dryness symptoms at month 2 after surgery.

Conclusion

Mild and moderate ocular pain were relatively common after 20G vitrectomy, which is more often associated with elevated IOP. Other irritation symptoms were also presented after surgery and could affect the life quality of patients. Therefore, the discomforts after 20G pars plana vitrectomy should be of concern, and timely management should be provided as part of routine postoperative care.