Diabetic Vitrectomy

Comparison of pars plana vitrectomy and combined pars plana vitrectomy with phacoemulsification for proliferative diabetic retinopathy: A retrospective study about 120 eyes

PURPOSE

To compare the outcomes of pars plana vitrectomy (PPV) and combined PPV with phacoemulsification (PPVCE) surgeries for proliferative diabetic retinopathy (PDR) and cataract treatment.

METHODS

Retrospective analysis of 120 diabetic patients who underwent PPV or PPVCE.

RESULTS

The key outcome indicators were best-corrected visual acuity (BCVA) and post-operative complications. The PPVCE group had an average age of 53 years, with 50% females and 50% males. The initial visual acuity (VA) was 1.84 log MAR. In this group, BCVA remained stable or increased in 61 eyes (74%). Regarding the PPV group, the average age was 43 years; 65% were men while 34% were women. The initial VA was 1.83 log MAR; in this group, the VA increased or remained stable in 28 eyes (73%). The evolution of the VA was rather symmetric in the two groups without a significant difference (P = 0.9). Similarly, the occurrence of postoperative complications was comparable for the main complications studied, namely the inflammatory reaction (P = 0.809), ocular hypertension (P = 0.344), corneal edema (P = 0.07), and neovascular glaucoma (P = 0.413). However, there was a decrease in BCVA (three lines) in the PPV group after 6 months of follow-up (P = 0.05) in patients with a clear lens preoperatively and who developed a clinically evident cataract.

CONCLUSION

According to this study, for diabetic patients with severe cataracts and vitreoretinal disease requiring vitrectomy, combining vitrectomy with phacoemulsification as a single surgical intervention may be a suitable therapeutic choice. This approach does not significantly increase the risk of visual impairment or retinopathy development.

Anti-vascular endothelial growth factors in combination with vitrectomy for complications of proliferative diabetic retinopathy

BACKGROUND

Vitrectomy is an established treatment for the complications of proliferative diabetic retinopathy (PDR). However, a number of complications can occur during and after vitrectomy for PDR. These include bleeding and the creation of retinal holes during surgery, and bleeding, retinal detachment and scar tissue on the retina after surgery. These complications can limit vision, require further surgery and delay recovery. The use of anti-vascular endothelial growth factor (anti-VEGF) agents injected into the eye before surgery has been proposed to reduce the occurrence of these complications. Anti-VEGF agents can reduce the amount and vascularity of abnormal new vessels associated with PDR, facilitating their dissection during surgery, reducing intra- and postoperative bleeding, and potentially improving outcomes.

OBJECTIVES

To assess the effects of perioperative anti-VEGF use on the outcomes of vitrectomy for the treatment of complications for proliferative diabetic retinopathy (PDR).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; which contains the Cochrane Eyes and Vision Trials Register; 2022, Issue 6); Ovid MEDLINE; Ovid Embase; the ISRCTN registry; ClinicalTrials.gov and the WHO ICTRP. The date of the search was 22 June 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that looked at the use of anti-VEGFs and the incidence of complications in people undergoing vitrectomy for PDR.   DATA COLLECTION AND ANALYSIS: Two review authors independently assessed and extracted the data. We used the standard methodological procedures expected by Cochrane. The critical outcomes of the review were the mean difference in best corrected visual acuity (BCVA) between study arms at six (± three) months after the primary vitrectomy, the incidence of early postoperative vitreous cavity haemorrhage (POVCH, within four weeks postoperatively), the incidence of late POVCH (occurring more than four weeks postoperatively), the incidence of revision surgery for POVCH within six months, the incidence of revision surgery for recurrent traction/macular pucker of any type and/or rhegmatogenous retinal detachment within six months and vision-related quality of life (VRQOL) measures. Important outcomes included the proportion of people with a visual acuity of counting fingers (1.8 logMAR or worse), the number of operative retinal breaks reported and the frequency of silicone oil tamponade required at time of surgery.

MAIN RESULTS

The current review includes 28 RCTs that looked at the pre- or intraoperative use of intravitreal anti-VEGFs to improve the outcomes of pars plana vitrectomy for complications of PDR. The studies were conducted in a variety of countries (11 from China, three from Iran, two from Italy, two from Mexico and the remaining studies from South Korea, the UK, Egypt, Brazil, Japan, Canada, the USA, Indonesia and Pakistan). The inclusion criteria for entry into the studies were the well-recognised complications of proliferative retinopathy: non-clearing vitreous haemorrhage, tractional retinal detachment involving the macula or combined tractional rhegmatogenous detachment. The included studies randomised a total of 1914 eyes.  We identified methodological issues in all of the included studies. Risk of bias was highest for masking of participants and investigators, and a number of studies were unclear when describing randomisation methods and sequence allocation. Participants receiving intravitreal anti-VEGF in addition to pars plana vitrectomy achieved better BCVA at six months compared to people undergoing vitrectomy alone (mean difference (MD) -0.25 logMAR, 95% confidence interval (CI) -0.39 to -0.11; 13 studies, 699 eyes; low-certainty evidence). Pre- or intraoperative anti-VEGF reduced the incidence of early POVCH (12% versus 31%, risk ratio (RR) 0.44, 95% CI 0.34 to 0.58; 14 studies, 1038 eyes; moderate-certainty evidence). Perioperative anti-VEGF use was also associated with a reduction in the incidence of late POVCH (10% versus 23%, RR 0.47, 95% CI 0.30 to 0.74; 11 studies, 579 eyes; high-certainty evidence). The need for revision surgery for POVCH occurred less frequently in the anti-VEGF group compared with control, but the confidence intervals were wide and compatible with no effect (4% versus 13%, RR 0.44, 95% CI 0.15 to 1.28; 4 studies 207 eyes; moderate-certainty evidence). Similar imprecisely measured effects were seen for revision surgery for rhegmatogenous retinal detachment (5% versus 11%, RR 0.50, 95% CI 0.15 to 1.66; 4 studies, 145 eyes; low-certainty evidence).  Anti-VEGFs reduce the incidence of intraoperative retinal breaks (12% versus 31%, RR 0.37, 95% CI 0.24 to 0.59; 12 studies, 915 eyes; high-certainty evidence) and the need for silicone oil (19% versus 41%, RR 0.46, 95% CI 0.27 to 0.80; 10 studies, 591 eyes; very low-certainty evidence). No data were available on quality of life outcomes or the proportion of participants with visual acuity of counting fingers or worse.

AUTHORS' CONCLUSIONS

The perioperative use of anti-VEGF reduces the risk of late POVCH, probably results in lower early POVCH risk and may improve visual outcomes. It also reduces the incidence of intraoperative retinal breaks. The evidence is very uncertain about its effect on the need for silicone oil tamponade. The reported complications from its use appear to be low. Agreement on variables included and outcome standardisation is required in trials studying vitrectomy for PDR.

PARS PLANA VITRECTOMY WITH and WITHOUT ILM-PEELING for DIABETIC PATIENTS with MACULA INVOLVED TRACTIONAL RETINAL DETACHMENT

PURPOSE

To evaluate the effect of internal limiting membrane (ILM) peeling on anatomical and functional results in pars plana vitrectomy (PPV) performed eyes with tractional retinal detachment affecting the macula due to diabetes mellitus (DM).

METHODS

Patients without ILM peeling were considered as Group 1, and with ILM peeling were considered as Group 2. The main outcomes were the best-corrected visual acuity (BCVA) at 6 months, and the rate of epiretinal membrane (ERM) formation within 6 months. The rate and the indications for resurgery were determined. Parameters affecting final BCVA were determined by regression analysis.

RESULTS

Final BCVA was significantly better in eyes with ILM-peeled off than in eyes with no peel-off (p=0.012). Less secondary ERM was formed in Group 1 (p=0.009). There was no difference between groups in terms of resurgery rates. (p=0.143). The need for resurgery due to ERM was higher in Group 1 rather than Group 2 (p=0.001). The only factor affecting final BCVA was ILM peeling.

CONCLUSION

In patients with tractional retinal detachment affecting the macula due to diabetes, ILM peeling in addition to PPV and membrane excision does not affect the need for resurgery but contributes positively to anatomical and functional outcomes.

The Effect of Internal Limiting Membrane Cleaning on Epiretinal Membrane Formation after Vitrectomy for Proliferative Diabetic Retinopathy

PURPOSE

We hypothesised that cleaning the internal limiting membrane (ILM) with a flexible nitinol loop following diabetic vitrectomy without peeling may reduce the common occurrence of postoperative epiretinal membrane (ERM) formation.

METHODS

Consecutive patients undergoing vitrectomy for proliferative diabetic retinopathy by one surgeon from 2015 to 2019 were studied and divided into 2 cohorts: the control group underwent standard surgery, and the ILM clean group underwent additional cleaning of the macular retina using a flexible nitinol loop after vitrectomy. Masked comparison of ERM on optical coherence tomography was performed at 3 months, and visual acuity (VA) was measured until 12 months postoperatively.

RESULTS

Baseline demographics, clinical features, and protein levels were similar between cohorts. The ILM clean group (n = 56) had fewer clinically significant ERM than the control group (n = 50; 4 vs. 20%; p = 0.01), and a significantly lower proportion of the ILM clean group required revision surgery (2 vs. 14%; p = 0.02). VA in the ILM clean group was significantly better than in the control group at 3 months (0.35 vs. 0.50 logMAR; p = 0.02) but not at 12 months (0.34 vs. 0.43 logMAR; p = 0.17).

CONCLUSION

ILM cleaning with a flexible nitinol loop following diabetic vitrectomy resulted in significant reduction in ERM formation and reduced necessity for revision surgery. There was significant improvement in VA at 3 months but not over a longer follow-up.

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.

Current management of diabetic tractional retinal detachments

Twenty-five percent of diabetes-related vision loss stems from complications of proliferative diabetic retinopathy (PDR). Panretinal photocoagulation has been the preferred treatment of high-risk PDR for decades and more recently intravitreal injections of drugs that inhibit the actions of vascular endothelial growth factor have become popular. But despite these treatments PDR may progress uncontrollably to advanced pathologies such as traction retinal detachments (TRDs), combined traction/rhegmatogenous retinal detachments (TRD/RRDs), vitreous hemorrhages, rubeosis iridis, and traction maculopathies, which produce mild-to-severe loss of vision. TDR have long been the most common indication for PDR-related vitreoretinal surgery. Vitrectomy surgery is indicated for recent (<6 months duration) TRD involving the macula, progressive TRD that threatens the macula, and recent data suggest that chronic macula-involving TRDs (>6 months duration) may also benefit. Combined TRD/RRD represents a particularly challenging surgical condition but advances in surgical instrumentation, dissection techniques, and post-operative tamponade have produced excellent success rates. The recent development of small-gauge vitrectomy systems has persuaded most surgeons to switch platforms since these appear to produce shorter surgical times and quicker post-operative recoveries. Pre-operative injections of bevacizumab are frequently administered for persistent neovascularization to facilitate surgical dissection of pre-retinal fibrosis and reduce the incidence of post-operative hemorrhages. Recent trends toward earlier surgical intervention and expanded indications are likely to continue as surgical instrumentation and techniques are further developed.

COMPLEX RETINAL DETACHMENT IN PHAKIC PATIENTS: Previtrectomy Phacoemulsification Versus Combined Phacovitrectomy

Previtrectomy cataract surgery was associated with less extensive postoperative posterior synechia, however, its final functional and anatomical outcomes were not significantly different from those of combined phacovitrectomy. Both approaches were efficacious.

Purpose:

To assess the impact of phacoemulsification performed one week before pars plana vitrectomy versus combined phacovitrectomy on postoperative anterior segment status and final functional and anatomical outcomes in phakic patients affected by complex rhegmatogenous retinal detachment.

Methods:

The authors retrospectively reviewed the records of 59 phakic patients affected by complex rhegmatogenous retinal detachment. Twenty-nine patients underwent cataract surgery 7 days before vitrectomy (preemptive cataract surgery—Group 1), whereas 30 patients underwent combined phacovitrectomy (Group 2). Preoperative, intraoperative, early- and late-postoperative outcomes were measured and compared.

Results:

Numbers of previous retinal surgical procedures, nuclear sclerosis grade, proliferative vitreoretinopathy grade, eyes with inferior breaks, surgical time, and ratio of silicone oil/gas tamponade were all similar between the two groups. After surgery, there was less extension of posterior synechia in Group 1. There was no significant difference in fibrin, number of patients with posterior synechia, final intraocular pressure, retinal redetachment rate, final retinal status, or final best-corrected visual acuity.

Conclusion:

Preemptive cataract surgery was associated with less extensive postoperative posterior synechia, however, its final functional and anatomical outcomes were not significantly different from those of phacovitrectomy. Both approaches were efficacious.

Differential association of elevated inflammatory cytokines with postoperative fibrous proliferation and neovascularization after unsuccessful vitrectomy in eyes with proliferative diabetic retinopathy

BACKGROUND

Pars plana vitrectomy is the only treatment for advanced proliferative diabetic retinopathy (PDR). However, vitrectomy is not always successful despite current progress in vitreoretinal surgical techniques. The aim of our study was to investigate whether the vitreal concentrations of MCP-1, IL-6, IL-8, and VEGF are elevated after unsuccessful vitrectomy in patients with PDR and to investigate whether the altered levels of these cytokines are associated with the cause for the reoperation.

PATIENTS AND METHODS

Vitreous samples were collected from 263 eyes of 233 patients: PDR (n=129 eyes), proliferative vitreoretinopathy (PVR; n=24 eyes) and nondiabetic controls (n=110 eyes) prior to vitrectomy. Vitreous samples were also collected from 14 eyes of 14 patients with PDR before vitrectomy and from the same 14 eyes before a second vitrectomy for reoperation. The levels of MCP-1, IL-6, IL-8, and VEGF were measured by flow cytometry using a cytometric bead array (CBA) assay.

RESULTS

The mean concentrations of vitreal MCP-1, IL-6, IL-8, and VEGF were significantly higher in patients with PDR and PVR (P<0.01). There were significantly high correlations among the concentrations of MCP-1, IL-6, and IL-8, whereas the correlation of VEGF with the other 3 cytokines was lower. Among the 14 patients who required reoperation, the mean vitreal concentrations of MCP-1, IL-6, and IL-8 were higher than that at the time of the initial vitrectomy (P<0.01). At the time of the reoperation vitrectomy, the mean vitreous level of MCP-1, IL-6, and IL-8 in eyes with fibrous proliferation was higher than in those without fibrous proliferation (P<0.05). In contrast, VEGF in eyes with neovascular glaucoma (NVG) or anterior hyaloidal fibrovascular proliferation (AHFVP) was higher than in the eyes without NVG and AHFVP (P<0.05).

CONCLUSION

The elevated levels of MCP-1, IL-6, and IL-8 may be the cause of the postoperative fibrous proliferation. In contrast, VEGF may be the cause of the neovascularization after unsuccessful vitrectomy in the eyes of PDR patients.

Ranibizumab pretreatment in diabetic vitrectomy: a pilot randomised controlled trial (the RaDiVit study)

PurposeOur aim was to evaluate the impact of intravitreal ranibizumab pretreatment on the outcome of vitrectomy surgery for advanced proliferative diabetic retinopathy. The objective was to determine the feasibility of a subsequent definitive trial and estimate the effect size and variability of the outcome measure.Patients and methodsWe performed a pilot randomised double-masked single-centre clinical trial in 30 participants with tractional retinal detachment associated with proliferative diabetic retinopathy. Seven days prior to vitrectomy surgery, participants were randomly allocated to receive either intravitreal ranibizumab (Lucentis, Novartis Pharmaceuticals UK Ltd, Frimley, UK) or subconjunctival saline (control). The primary outcome was best-corrected visual acuity 12 weeks following surgery.ResultsAt 12 weeks, the mean (SD) visual acuity was 46.7 (25) ETDRS letters in the control group and 52.6 (21) letters in the ranibizumab group. Mean visual acuity improved by 14 (31) letters in the control group and by 24 (27) letters in the ranibizumab group. We found no difference in the progression of tractional retinal detachment prior to surgery, the duration of surgery, or its technical difficulty. Vitreous cavity haemorrhage persisted at 12 weeks in two of the control group but none of the ranibizumab group.ConclusionRanibizumab pretreatment may improve the outcome of vitrectomy surgery for advanced proliferative diabetic retinopathy by reducing the extent of post-operative vitreous cavity haemorrhage. However, the effect size appears to be modest; we calculate that a definitive study to establish a minimally important difference of 5.9 letters at a significance level of P<0.05 would require 348 subjects in each arm.

The kinetics of VEGF and MCP-1 in the second vitrectomy cases with proliferative diabetic retinopathy

PurposeTo determine whether the concentrations of vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein (MCP)-1 in the vitreous changed after vitrectomy in patients with proliferative diabetic retinopathy (PDR).ParticipantsTwenty-one eyes of 21 patients who needed a second surgery for PDR were included. The reasons for the second surgery were tractional retinal detachment (TRD), neovascular glaucoma, persistent vitreous hemorrhage, macular pucker, and secondary intraocular lens (IOL) implant.MethodsWe measured the VEGF and MCP-1 levels using sandwich enzyme-linked immunosorbent assays in vitreous samples collected from patients with PDR before pars plana vitrectomy (without IOL implantation), and from the same patients during the second surgery.ResultsThere was not significant change in mean VEGF concentrations when comparing first (0.81±0.88 ng/ml) and second surgeries (1.09±1.51 ng/ml). The MCP-1 level was significantly elevated at the time of second surgery (2.20±2.21 ng/ml) compared with the first vitrectomy (0.72±0.57 ng/ml). The MCP-1 levels of the second surgery cases with TRD (3.18±2.27 ng/ml) increased significantly compared with those with other complications (1.72±2.10 ng/ml).ConclusionsAt the second vitrectomy, VEGF did not change significantly in the vitreous of the patients examined. The MCP-1 concentration was markedly elevated at the second vitrectomy, implying an association between the prolonged inflammation after vitrectomy and complications, especially TRD.

Anti-vascular endothelial growth factor for prevention of postoperative vitreous cavity haemorrhage after vitrectomy for proliferative diabetic retinopathy

BACKGROUND

Postoperative vitreous cavity haemorrhage (POVCH) is a significant complication following vitrectomy for proliferative diabetic retinopathy (PDR). It delays visual recovery and can make further treatment difficult if the view of the fundus is significantly obscured. A number of interventions to reduce the incidence of POVCH have been proposed, including the perioperative use of anti-vascular endothelial growth factor (anti-VEGF). Anti-VEGFs reduce vascular proliferation and the vascularity of neovascular tissue, which is often the source of bleeding following vitrectomy.

OBJECTIVES

This updated review aimed to summarise the effects of anti-VEGF use to reduce the occurrence of POVCH after vitrectomy surgery for PDR.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2015, Issue 4), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to May 2015), PubMed (January 1966 to May 2015), EMBASE (January 1980 to May 2015), Latin American and Caribbean Health Sciences (LILACS) (January 1982 to May 2015), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 26 May 2015.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) and quasi-RCTs that looked at the use of anti-VEGFs and the incidence of POVCH in people undergoing vitrectomy for PDR.

DATA COLLECTION AND ANALYSIS

Both review authors independently assessed and extracted the data. We used standard methodological procedures expected by Cochrane.The primary outcomes of the review were the incidence of early and late POVCH following perioperative anti-VEGF administration. Secondary outcomes included best-corrected visual acuity at six months following surgery, the incidence of vitreous cavity washout or revision vitrectomy at six months, adverse effects of intervention (cataract, iris rubeosis and rubeotic glaucoma, retinal detachment, increased inflammation and systemic side effects), quality of life measures performed at least six months following vitrectomy, and density of POVCH.

MAIN RESULTS

The current review included 12 RCTs that looked at the pre- or intraoperative use of intravitreal bevacizumab to prevent postoperative vitreous haemorrhage during pars plana vitrectomy for complications of PDR. The studies were conducted in a variety of countries (three from Iran, two from Italy, two from Egypt, and the remaining from South Korea, USA, Mexico, Pakistan, and Japan). The inclusion criteria for entry into the studies were standard complications of proliferative retinopathy: non-clearing vitreous haemorrhage, tractional retinal detachment involving the macula, or combined tractional rhegmatogenous detachment. The included studies randomised a total of 654 eyes. The average age of the participants was 54 years.We identified methodological issues in all included studies. Risk of bias was highest for masking of participants and investigators (four studies were an 'open label' design), and a number of studies were unclear when describing randomisation methods and sequence allocation.Participants receiving intravitreal bevacizumab in addition to pars plana vitrectomy were less likely to experience early POVCH (grade 2) compared to people undergoing pars plana vitrectomy alone (risk ratio (RR) 0.28, 95% confidence interval (CI) 0.08 to 0.96, 2 studies, 144 eyes, high-quality evidence). This corresponds to an absolute effect of 130 fewer people (95% CI 167 fewer to 7 fewer) with early POVCH per 1000 people when treated with intravitreal bevacizumab. We saw similar results for all grades of POVCH (RR 0.35, 95% CI 0.23 to 0.53, 9 studies, 512 eyes) and when excluding cases where assessment of outcome was impossible due to presence of silicone oil (RR 0.34, 95% CI 0.19 to 0.60, 6 studies, 302 eyes).The effect of pre- or intraoperative intravitreal bevacizumab on the incidence of late postoperative haemorrhage was uncertain (RR 0.72, 95% CI 0.30 to 1.72, 3 studies, 196 eyes, low-quality evidence). The absolute effect was 55 fewer people (95% CI 138 fewer to 143 more) with late POVCH per 1000 people when treated with intravitreal bevacizumab. This outcome was rarer and was only reported in a few studies. We are currently unable to provide an estimate of the effect of intravitreal bevacizumab on postoperative visual acuity due to significant study heterogeneity.No local or systemic complications of intravitreal bevacizumab were reported by the RCTs. The risk of postoperative retinal detachment was lower in the participants treated with pre- or intraoperative bevacizumab (RR 0.46, 95% CI 0.19 to 1.08, 7 studies, 372 participants, low-quality evidence); the absolute effect was 49 fewer people (95% CI:73 fewer to 8 more) with postoperative retinal detachment per 1000 people when treated with intravitreal bevacizumab.

AUTHORS' CONCLUSIONS

The use of pre- or intraoperative bevacizumab lowers the incidence of early POVCH. The reported complications from its use appear to be low. Futher randomised studies that look at other anti-VEGF medications are ongoing and will strengthen the current review findings, giving both surgeons and patients evidence to guide treatment choices in the management of proliferative retinopathy.

Combined 23-gauge sutureless vitrectomy and clear corneal phacoemulsification for rhegmatogenous retinal detachment repair

AIM

To assess the outcomes of combined 23-gauge sutureless vitrectomy and clear corneal phacoemulsification with intraocular lens implantation for rhegmatogenous retinal detachment (RRD) repair.

METHODS

This was a retrospective, consecutive, non-comparative, interventional case series of 30 eyes of 30 patients who underwent combined sutureless vitrectomy and clear corneal cataract surgery for the repair of RRD. The principal outcome measures were primary anatomical success rate, reasons for redetachment, final visual acuity, and surgical complications.

RESULTS

Primary reattachment was achieved in 27 eyes (90.0%). The reasons for redetachment (3 eyes, 10%) were incomplete laser retinopexy, persistent chronic subretinal fluid, and proliferative vitreoretinopathy, respectively. The logarithm of the minimum angle of resolution visual acuity (mean±SD) improved from 0.76±0.74 preoperatively to 0.21±0.37 6 months' postoperatively (P<0.0001). Postoperative hypotony was not detected, but 1 eye (3.3%) had increased intraocular pressure (30mmHg) with spontaneous resolution. No endophthalmitis developed during follow-up. Macular pucker was detected in 3 eyes (10.0%).

CONCLUSION

Combined 23-gauge sutureless vitrectomy and clear corneal phacoemulsification with intraocular lens implantation for RRD repair was proven safe and effective. It may provide not only the known advantages of conventional combined surgery, but also additional advantages such as less conjunctival fibrosis and the maintenance of stable intraocular pressure with low risks of postoperative hypotony and intraocular pressure elevation.

Comparison of combined and sequential surgery for proliferative diabetic retinopathy: a single surgeon study

Purpose

To compare the results of combined and consecutive surgeries to treat proliferative diabetic retinopathy and cataract.

Methods

Retrospective comparative study. Forty-one patients with proliferative diabetic retinopathy (PDR) were enrolled. Twenty-nine eyes for the combined surgery group and twelve eyes for the sequential group were included. All surgeries were performed by one surgeon. Phacoemulsification was performed using a clear cornea incision. The vitrectomy was performed using a 20-gauge vitreous cutter.

Results

The best corrected visual acuity (BCVA) and intra- and post-operative complications were the main outcome measures. In the combined surgery group, the BCVA increased in 18 (62.1%) eyes, while eight (27.6%) eyes remained stable and three (10.3%) eyes decreased. Postoperative complications included fibrinous exudation in nine eyes, macular edema in three eyes and vitreous hemorrhage in three eyes. In the sequential surgery group, the BCVA increased in seven (58.3%) eyes, remained the same in four (33.3%) eyes and was reduced in one (8.3%) eye. Postoperative complications included macular edema in two eyes, neovascular glaucoma in two eyes and vitreous hemorrhage in one eye.

Conclusions

Both combined and sequential surgeries are safe and effective for treating PDR and cataracts. The combined surgery had a higher incidence of fibrinous exudation.

Ahmed valve implantation for neovascular glaucoma after 23-gauge vitrectomy in eyes with proliferative diabetic retinopathy

AIM

To report on the outcome of Ahmed glaucoma valve (AGV) implantation for the management of neovascular glaucoma (NVG) after 23-gauge vitrectomy for proliferative diabetic retinopathy (PDR).

METHODS

Twelve medically uncontrolled NVG with earlier 23-gauge vitrectomy for PDR underwent AGV implantation. The control of intraocular pressure (IOP), preoperative and postoperative best-corrected visual acuity, the development of intraoperative and postoperative complications were evaluated during the follow-up.

RESULTS

The mean follow-up was 15.4±4.3 months (9-23 months). Mean preoperative IOP was 49.4±5.1mmHg and mean postoperative IOP at the last visit was 17.5±1.6mmHg. The control of IOP was achieved at the final follow-up visits in all patients, however, 8 of 12 patients still needed anti-glaucoma medication (mean number of medications, 0.8±0.7). The visual acuity improved in nine eyes, and the visual acuity unchanged in three eyes at the final follow-up visits. The complications that occurred were minor hyphema in three eyes, choroid detachment in two eyes, and the minor hyphema and choroid detachments were reabsorbed without any surgical intervention.

CONCLUSION

AGV implantation is a safe and effective procedure that enables successful IOP control and vision preservation in the NVG patients with the history of earlier 23-gauge vitrectomy for PDR.

Surgical results of pars plana vitrectomy combined with pars plana lensectomy with anterior capsule preservation, endophotocoagulation, and silicon oil tamponade for neovascular glaucoma

Purpose

To report on pars plana vitrectomy (PPV) combined with pars plana lensectomy (PPL) with a preserved anterior capsule, panretinal endophotocoagulation (EPC) throughout the pars plana, and silicon oil (SO) tamponade (PPV + PPL + EPC + SO tamponade) for neovascular glaucoma (NVG).

Methods

Thirteen eyes with NVG were treated. Ten eyes also underwent SO removal and intraocular lens (IOL) implantation (SO removal + IOL). Intraocular pressure (IOP), number of medications, and visual acuity were evaluated at the first visit, immediately before and 3 months after the procedure, 3 months after SO removal + IOL, and 1 year after the procedure.

Results

At the first visit, immediately before and 3 months after the procedure, 3 months after SO removal + IOL, and 1 year after the procedure, the IOPs were 29 ± 19, 23 ± 12, 13 ± 5, 17 ± 10, and 17 ± 6 mmHg; numbers of medications, 0.7 ± 1.4, 2.1 ± 2.0, 0.6 ± 0.7, 1.2 ± 1.2, and 1.6 ± 1.6; and best-corrected visual acuities converted to logarithm of the minimum angle of resolution (BCVA logMAR), 0.96 ± 0.96, 1.27 ± 0.80, 1.67 ± 0.91, 1.37 ± 0.89, and 1.90 ± 1.44, respectively. No severe hypotony or phthisis bulbi developed within 1 year after the procedure. The success rates (IOP ≤ 21 mmHg and sustained light perception) were 92.3% after 3 months and 69.2% after 1 year.

Conclusion

PPV + PPL + EPC + SO tamponade might have prevented acute increases of vascular endothelial growth factor and inflammatory cytokine production postoperatively and resulted in good vision in patients with NVG.

Outcomes and complications of 25-gauge transconjunctival sutureless vitrectomy for proliferative diabetic retinopathy

PURPOSE

To investigate the feasibility and efficacy of 25-gauge vitrectomy in the treatment of proliferative diabetic retinopathy (PDR).

METHODS

All patients underwent primary 25-gauge vitrectomy for simple vitreous hemorrhage (VH), fibrovascular proliferation (FVP), or tractional retinal detachment (TD), and were followed for more than 1 month. Final visual outcomes and intraoperative and postoperative complications were evaluated.

RESULTS

167 eyes (138 patients) were used in this study, 65 eyes (39%) with VH, 66 eyes (40%) with FVP, and 36 eyes (21%) with TD. Measured using the mean logarithm of the minimum angle of resolution (logMAR), visual acuity (VA) significantly improved (p < 0.0001). Intraoperative iatrogenic retinal breaks developed in 19 eyes (11%). Concerning postoperative complications, VH in 36 eyes (22%), retinal detachment in 2 eyes (1%), and neovascular glaucoma 12 eyes (7%) were observed. No endophthalmitis developed.

CONCLUSIONS

Twenty-five-gauge vitrectomy can successfully treat PDR. Clinical outcomes and complications are comparable to those of 20-gauge vitrectomy.

Anti-vascular endothelial growth factor for prevention of postoperative vitreous cavity haemorrhage after vitrectomy for proliferative diabetic retinopathy

BACKGROUND

Postoperative vitreous cavity haemorrhage (POVCH) is a significant complication following vitrectomy for proliferative diabetic retinopathy (PDR). It delays visual recovery and can make further treatment difficult if the view of the fundus is significantly obscured. A number of interventions to reduce the incidence of POVCH have been proposed, including the perioperative use of anti-vascular endothelial growth factor (anti-VEGF). Anti-VEGFs reduce vascular proliferation and the vascularity of neovascular tissue, which is often the source of bleeding following vitrectomy.

OBJECTIVES

The review aims to assess the effect of perioperative anti-VEGF in reducing the incidence of POVCH.

SEARCH STRATEGY

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2011, Issue 2), MEDLINE (January 1950 to March 2011), PubMed (10 March 2011), EMBASE (January 1980 to March 2011), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to March 2011), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) and ClinicalTrials.gov (www.clinicaltrial.gov). There were no date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 10 March 2011.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) that looked at the use of anti-VEGFs and the incidence of POVCH in people undergoing vitrectomy for PDR.

DATA COLLECTION AND ANALYSIS

Both review authors independently assessed and extracted the data using a standardised form based on the CONSORT statement.

MAIN RESULTS

We included four studies (202 eyes of 198 participants) in this review. The four RCTs met the inclusion criteria, but we were unable to conduct a meta-analysis due to methodological issues in three of the trials. We have provided a summary of the effects of the interventions. We have also provided a summary of the current literature addressing each primary and secondary outcome.

AUTHORS' CONCLUSIONS

Results from one of the included studies support the use of preoperative intravitreal bevacizumab to reduce the incidence of early POVCH. There are currently no other high quality RCTs that support the use of anti-VEGF agents perioperatively to reduce the incidence of early or late POVCH. The remaining studies identified by the search suggest that the preoperative use of bevacizumab may reduce the incidence of early POVCH, but it should be recognised that there are a number of significant methodological issues in these studies that lead us to be cautious when interpreting their findings and make any definitive conclusions unwarranted.

Vitreous hemorrhage after the 25-gauge transconjunctival sutureless vitrectomy for proliferative diabetic retinopathy

PURPOSE

To address the incidence, clinical course, and risk factors for postoperative vitreous hemorrhage (PVH) after a 25-gauge transconjunctival sutureless vitrectomy for proliferative diabetic retinopathy.

METHODS

A consecutive series of eyes underwent 25-gauge transconjunctival sutureless vitrectomies for proliferative diabetic retinopathy. The best-corrected visual acuities and intraocular pressures were measured, and the complications were prospectively evaluated 1 day, 1 week, 1 month, and 3 months postoperatively, then as needed.

RESULTS

The mean postoperative follow-up was 11.0 ± 6.3 months (range, 6-28 months). Of 93 eyes, 42 had PVH on Day 1 (immediate PVH) but the presence and degree of PVH did not affect visual recovery and only 4 eyes did not clear for 1 month (persistent PVH). Recurrent PVH occurred in 11 eyes. Eight eyes had hypotony on Day 1, and patients who experienced postoperative hypotony had an 11.20-fold increased risk of immediate PVH > Grade 2. In the cases that needed intravitreal tamponade, the risk of recurrent PVH was 3.03-fold higher.

CONCLUSION

After 25-gauge transconjunctival sutureless vitrectomies for proliferative diabetic retinopathy, postoperative hypotony and the need for tamponade increased the rates of immediate and recurrent PVH, respectively. Immediate PVH occurred in 45.2% of the patients but did not affect early visual recovery. A 25-gauge transconjunctival sutureless vitrectomy resulted in a favorable incidence of recurrent PVH (11.8%) during the first 6 months.

Comparison of retinal breaks observed during 23 gauge transconjunctival vitrectomy versus conventional 20 gauge surgery for proliferative diabetic retinopathy

BACKGROUND

To assess the rate and type of retinal break formation in patients undergoing 23 gauge transconjunctival vitrectomy surgery for complications of proliferative diabetic retinopathy compared with 20 gauge vitrectomy surgery.

METHODS

Retrospective case notes review of two consecutive series of patients who had primary pars plana vitrectomy for complications of proliferative diabetic retinopathy by a single surgeon. The control group had standard 20 gauge vitrectomy surgery whilst the second group had 23 gauge transconjunctival vitrectomy surgery.

RESULTS

Eighty-five eyes were included in the 20 gauge group and 85 eyes in the 23 gauge group. The groups were well matched for surgical complexity and indications for surgery, as well as a variety of other preoperative variables. There was a significant reduction in the incidence of peripheral sclerotomy-related retinal breaks and lesions suspicious for breaks (4/85 [5%] 23 gauge versus 14/85 [16%] 20 gauge, P = 0.02) and posterior retinal breaks (3/85 [4%] 23 gauge versus 12/85 [14%] 20 gauge, P = 0.03). Six eyes (7%) in total had definite new retinal breaks of any type detected in the 23 gauge group compared with 16 (18.8%) in the 20 gauge group (P = 0.04). One patient in each group experienced a retinal detachment postoperatively related in both cases to a posterior retinal break associated with recurrent traction.

CONCLUSION

In this series of patients, 23 gauge transconjunctival vitrectomy surgery was associated with a lower rate of retinal break formation than 20 gauge vitrectomy for proliferative diabetic retinopathy.

Lensectomy using a bimanual microincision cataract surgery technique during pars plana vitrectomy

Lens extraction during vitrectomy is sometimes necessary to obtain an adequate view of the retina. Currently, phacoemulsification through a clear corneal incision with implantation of a foldable intraocular lens has become the preferred technique for cataract extraction during pars plana vitrectomy. The authors described the technique of lensectomy using a bimanual microincisional cataract surgery technique during pars plana vitrectomy and insertion of the intraocular lens at the end of surgery, which has several advantages over conventional coaxial phacoemulsification procedures.

Diabetic vitrectomy: the influence of lens status upon surgical outcomes

PURPOSE OF REVIEW

Management of the lens in diabetic eyes undergoing vitrectomy has long been a source of controversy. Initially, the lens was removed during diabetic vitrectomy because of intraoperative changes. It was noted, however, that anterior segment neovascular complications were greater in aphakic eyes after diabetic vitrectomy, and subsequently the vitreoretinal surgeon attempted to spare the lens. Lens management in this regard continues to attract discussion. This report reviews recent trends in the management of the native lens in the diabetic eye undergoing vitrectomy.

RECENT FINDINGS

The rate of cataract formation after diabetic vitrectomy is high in eyes left phakic. The rates of anterior segment neovascularization and retinal detachment after diabetic vitrectomy are similar in phakic and nonphakic eyes. The rate of subsequent reoperation after diabetic vitrectomy may be greater in eyes left phakic.

SUMMARY

Although the management of the lens in an eye undergoing diabetic vitrectomy should be individualized, cataract extraction performed either before or in combination with vitrectomy may reduce the rate of subsequent reoperation. The vitreoretinal surgeon may consider rendering an eye nonphakic before or during diabetic vitrectomy to optimize outcomes.