Prevalence and risk factors for proliferative vitreoretinopathy in eyes with rhegmatogenous retinal detachment but no previous vitreoretinal surgery

Association of Cutaneous Keloids, Hypertrophic Scarring, and Fibrosis with Risk of Postoperative Proliferative Vitreoretinopathy

PURPOSE

To assess an association between cutaneous keloids, hypertrophic scarring, and fibrosis (KHF) and risk of postoperative proliferative vitreoretinopathy (PVR) after rhegmatogenous retinal detachment (RRD) repair.

DESIGN

Retrospective, population-based cohort study.

PARTICIPANTS

Patients aged ≥ 18 years who underwent initial retinal detachment (RD) repair with pars plana vitrectomy with or without scleral buckle (SB) (Current Procedural Terminology [CPT] 67108), pneumatic retinopexy (67110), and primary SB (67107) from January 1, 2003, to March 1, 2023.

METHODS

A de-identified electronic health record database through TriNetX, a global health research network, was used to analyze patients. Patients were queried for International Classification of Diseases, 10th Revision (ICD-10) codes L91.0 (hypertrophic scar) and L90.5 (scar conditions and fibrosis of skin). Frequency of subsequent diagnosis of PVR (H35.2) and CPT codes for secondary surgery including complex RD repair (67113) were determined. Patients with proliferative diabetic retinopathy (PDR) (ICD-10 H10.35/H11.35) were excluded. Descriptive statistics (Z-test) and propensity score matching (PSM) were used to match for age, sex, and race.

MAIN OUTCOME MEASURES

Prevalence of H35.2 and CPT 67113 within 180 days after RRD repair in the KHF cohort versus the non-KHF cohort.

RESULTS

Among patients with CPT 67108, 1061 in each cohort (KHF and non-KHF) were analyzed after PSM. The mean (standard deviation) age was 60.7 (15.2) years. Within 180 days, 10.1% of patients in the KHF cohort and 3.4% in the non-KHF cohort had a diagnosis of PVR (H35.2) (P < 0.001, odds ratio [OR], 3.2; 95% confidence interval [CI], 2.13-4.71). A total of 8.3% of patients in the KHF cohort and 5.4% of patients in the non-KHF cohort underwent complex RD repair (CPT 67113) (P = 0.008; OR, 3.2; 95% CI, 1.13-2.25). When including all RD repair types (CPT 67108, 67110, 67107), the rate of PVR diagnosis was still significantly greater in the KHF cohort than in the non-KHF cohort (9.0% vs 4.2%, P < 0.01; OR, 2.28; 95% CI, 1.64-3.16).

CONCLUSIONS

A dermatologic history of KHF may be a risk factor for PVR after RD repair.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Outcomes of pars plana vitrectomy in the management and diagnosis of patients with infectious, non-infectious, and unidentified uveitis

PURPOSE

To present the outcomes of pars plana vitrectomy (PPV) in patients with infectious, non-infectious, and unidentified uveitis, focusing on visual and clinical outcomes, diagnostic yield, and surgery-related complications.

METHODS

This retrospective, single-center study included patients who underwent 23-gauge PPV for the management of uveitis and had at least 6 months of follow-up. Patients were divided into infectious, non-infectious, and unidentified uveitis groups based on definitive diagnosis after surgery. Etiologies of uveitis, indications for surgery, diagnostic yield, visual outcomes, presence of cystoid macular edema (CME), immunosuppressive drugs, intraoperative and postoperative complications, and repeated vitrectomies were reviewed.

RESULTS

This study included 62 eyes of 54 patients. Twenty eyes were diagnosed with infectious uveitis, 24 eyes with non-infectious uveitis, and 18 eyes with unidentified uveitis. The diagnostic yield of vitrectomy was 41.7%. Mean BCVA significantly improved at postoperative 1 month compared to baseline and remained stable at following time-points in all groups. The most common early postoperative complication was increased intraocular pressure (17%), and late complication was cataract (36%). Nine eyes underwent re-vitrectomy and the most common cause was retinal detachment with proliferative vitreoretinopathy (PVR).

CONCLUSION

PPV seems to be effective in diagnosing cases of unknown origin, improving visual acuity, and reducing the need for systemic immunosuppressive drugs. PVR is the most serious complication with poor prognosis that requires repeated surgery in patients with uveitis.

Risk factors for proliferative vitreoretinopathy after retinal detachment surgery: A systematic review and meta-analysis

BACKGROUND

To comprehensively investigate risk factors for proliferative vitreoretinopathy (PVR) after retinal detachment (RD) surgery.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science were systematically searched until May 22, 2023. Risk factors included demographic and disease-related risk factors. Odds ratios (ORs) and weighted mean differences (WMDs) were used as the effect sizes, and shown with 95% confidence intervals (CIs). Sensitivity analysis was conducted. The protocol was registered with PROSPERO (CRD42022378652).

RESULTS

Twenty-two studies of 13,875 subjects were included in this systematic review and meta-analysis. Increased age was associated with a higher risk of postoperative PVR (pooled WMD = 3.98, 95%CI: 0.21, 7.75, P = 0.038). Smokers had a higher risk of postoperative PVR than non-smokers (pooled OR = 5.07, 95%CI: 2.21-11.61, P<0.001). Presence of preoperative PVR was associated with a greater risk of postoperative PVR (pooled OR = 22.28, 95%CI: 2.54, 195.31, P = 0.005). Presence of vitreous hemorrhage was associated with a greater risk of postoperative PVR (pooled OR = 4.12, 95%CI: 1.62, 10.50, P = 0.003). Individuals with aphakia or pseudophakia had an increased risk of postoperative PVR in contrast to those without (pooled OR = 1.41, 95%CI: 1.02, 1.95, P = 0.040). The risk of postoperative PVR was higher among patients with macula off versus those with macula on (pooled OR = 1.85, 95%CI: 1.24, 2.74, P = 0.002). Extent of RD in patients with postoperative PVR was larger than that in patients without (pooled WMD = 0.31, 95%CI: 0.02, 0.59, P = 0.036). Patients with postoperative PVR had longer duration of RD symptoms than those without (pooled WMD = 10.36, 95%CI: 2.29, 18.43, P = 0.012).

CONCLUSION

Age, smoking, preoperative PVR, vitreous hemorrhage, aphakia or pseudophakia, macula off, extent of RD, and duration of RD symptoms were risk factors for postoperative PVR in patients undergoing RD surgery, which may help better identify high-risk patients, and provide timely interventions.

Safety profile and surgical outcomes of early vitrectomy in eyes with unexplained fundus-obscuring vitreous haemorrhage

OBJECTIVES

To investigate the safety profile and the surgical outcomes in a large cohort of subjects undergoing early vitrectomy for unexplained fundus-obscuring vitreous haemorrhage (FOVH).

METHODS

Retrospective, single-centre case series of 186 consecutive eyes presenting between January 2018 and February 2020. Primary outcomes included change in best-corrected visual acuity (BCVA), rate of intra-operative retinal tears or retinal detachment (RD), baseline proliferative vitreoretinopathy (PVR), association of demographics with clinical outcomes, and rate of significant adverse events characterised by reoperation.

RESULTS

Main final diagnosis was haemorrhagic posterior vitreous detachment (76%) and the overall risk of a retinal tear with or without RD found at the time of surgery was 69%. Vitrectomy was completed within 24 h in 94% of eyes. Rate of RD was 18%; all cases were macula-sparing with no PVR. Mean change in BCVA from baseline to final follow-up was -1.53 ± 0.69 LogMAR, p < 0.001. Time from presentation to surgery was significantly associated with final BCVA (p = 0.036, beta co-efficient 0.097). There was a significant association between presence of RD and age <60 y (OR 0.94, 95%CI [0.90-0.98], p = 0.003). 4.8% required repeated vitrectomy for post-operative RD (4), epiretinal membrane formation (3), removal of oil (1), and recurrent FOVH (1). None of these reoperations were induced by complications during the first surgery.

CONCLUSION

There is a high rate of retinal breaks in cases with unexplained FOVH, and the risk of a concomitant RD is higher in younger subjects. Early vitrectomy within 24 h appears a safe first-line treatment and yields good clinical outcomes.

Intravitreal Injection of Bevacizumab for the Prevention of Postoperative Proliferative Vitreoretinopathy in High-Risk Patients Selected by Laser Flare Photometry

INTRODUCTION

To evaluate the effect of an intravitreal injection of bevacizumab at the time of rhegmatogenous retinal detachment (RRD) surgery, on postoperative proliferative vitreoretinopathy (PVR) in high-risk patients selected by laser flare photometry.

METHODS

This single-center observational retrospective cohort study included 137 consecutive patients who underwent pars plana vitrectomy and gas tamponade for primary RRD with increased aqueous flare between July 2016 and June 2021. From June 2019, an intravitreal injection of bevacizumab was administered as an adjunct to RRD repair. Patients who underwent surgery before this time and who did not receive intravitreal bevacizumab served as controls. The main outcome was the rate of retinal redetachment due to PVR.

RESULTS

The median flare value was 22.0 (16.5-36.5) pc/ms in the control group and 28.2 (19.7-41.0) pc/ms in the bevacizumab group (p = 0.063). Eyes treated with bevacizumab were more likely to have macula-off RRD (p = 0.003), grade B PVR (p = 0.038), and worse visual acuity (p = 0.004) than controls. The rate of PVR redetachment was significantly lower in the bevacizumab group (11.1%) than in the control (30.1%) (p = 0.012). This difference was more pronounced after adjusting for potential confounding factors (p = 0.005); the risk of developing PVR was 4.5-fold higher in controls (95% CI, 1.6-12.8). After adjustment, the final median visual acuity was also significantly higher in eyes treated with bevacizumab (p = 0.025).

CONCLUSION

This pilot study provides preliminary evidence that bevacizumab may reduce the risk of PVR-related recurrent RRD and improve visual outcomes in high-risk patients selected by laser flare photometry.

Vitreal Concentrations of Vascular Endothelial Growth Factor in Patients with Rhegmatogenous Retinal Detachment

The purpose of this study is to evaluate the concentration of vascular endothelial growth factor (VEGF) in the vitreous humor of patients with primary rhegmatogenous retinal detachment (RRD). This is a prospective case control study. Eighteen patients with primary RRD without proliferative vitreoretinopathy C (PVR C) were enrolled as cases, and twenty-two non-diabetic retinopathy patients who were candidates for complete pars plana vitrectomy due to Macular Hole or Epiretinal Membrane were included as the control group. Undiluted vitreal samples were collected during the initiation of Pars Plana Vitrectomy (PPV) prior to any infusion into the posterior cavity. Vitreous samples were also collected from 21 fresh cadaveric globes. The vitreous concentration of VEGF was measured by enzyme-linked immunosorbent assay (ELISA) technique and compared between these two groups. The vitreal concentration of VEGF was 0.643 ± 0.088 ng/mL in the RRD group. Measured concentrations of VEGF in controls were 0.043 ± 0.104 ng/mL, and in cadaveric eyes they were 0.033 ± 0.058 ng/mL. The mean VEGF concentration in the RRD group was statistically higher than in the control group (p < 0.0001) and cadaveric eyes (p < 0.0001). Our study shows that vitreal VEGF concentrations significantly increase in patients with RRD.

Role of Oxidative Stress in Ocular Diseases: A Balancing Act

Redox homeostasis is a delicate balancing act of maintaining appropriate levels of antioxidant defense mechanisms and reactive oxidizing oxygen and nitrogen species. Any disruption of this balance leads to oxidative stress, which is a key pathogenic factor in several ocular diseases. In this review, we present the current evidence for oxidative stress and mitochondrial dysfunction in conditions affecting both the anterior segment (e.g., dry eye disease, keratoconus, cataract) and posterior segment (age-related macular degeneration, proliferative vitreoretinopathy, diabetic retinopathy, glaucoma) of the human eye. We posit that further development of therapeutic interventions to promote pro-regenerative responses and maintenance of the redox balance may delay or prevent the progression of these major ocular pathologies. Continued efforts in this field will not only yield a better understanding of the molecular mechanisms underlying the pathogenesis of ocular diseases but also enable the identification of novel druggable redox targets and antioxidant therapies.

Sustained impact of COVID-19 on primary retinal detachment repair in a tertiary eye hospital from March to December 2020

Purpose

To review the sustained effect of COVID-19 on rhegmatogenous retinal detachment (RRD) baseline characteristics and outcomes.

Methods

This was a retrospective consecutive case series at the Birmingham and Midlands Eye Centre including patients undergoing primary RRD repair between 23 March and 31 December 2017-2019 (Group 1) and 2020 (Group 2). The deciles of indices of multiple deprivation (IMD) were determined by postcode to group patients into least deprived (IMD1-5) and most deprived (IMD6-10).

Results

In total we reviewed 1310 patients, 1003 in Group 1 and 307 in Group 2. Relative to 2017-2019, during the first lockdown, we observed (a) a reduction in the number of patients with RRD, (b) an increase in macula-off detachments, (c) an increase in RRD primary failure, and (d) that the least deprived had proportionately higher primary failure than the most deprived (p = 0.049) with a higher detachment rate than the pre-COVID-19 period (p = 0.010) and increased presentations of macula-off detachment. During the second lockdown, these differences were not observed.

Conclusion

The previously observed findings of lower presentation rates of RRD during the beginning of the first lockdown and the decreased number of macula-on RRD were not sustained over a longer period of observation or found to recur after a second national lockdown. Patients from areas with the least socioeconomic deprivation seemed to be more negatively affected by the first lockdown, with later presentation and higher rates of re-detachments compared with the most deprived during the first lockdown. Our findings offer reassurance that patient behaviour and health services had adapted to the pandemic by the second national lockdown.

Supplementary Information

The online version of this article (10.1007/s00717-022-00521-0) contains supplementary material, which is available to authorized users.

Recurrent retinal detachment after pars plana vitrectomy with silicone oil tamponade for rhegmatogenous retinal detachment

BACKGROUND

The recurrence of retinal detachment following rhegmatogenous retinal detachment (RRD) is a relatively common complication that can lead to reduced visual acuity and requires further surgery. The purpose of this study was to investigate the risk factors and visual outcomes of recurrent RRD following pars plana vitrectomy (PPV) with silicone oil tamponade for primary RRD.

METHODS

This was a retrospective follow-up study of 343 eyes that underwent initial PPV surgery with silicone oil tamponade for primary RRD. Patients were divided into a recurrence group and a reattachment group. The main outcome measures included causative factors, visual outcomes related to the recurrence of RRD, and the perioperative factors most affecting the recurrence of RRD.

RESULTS

After retinal reattachment, we observed RRD recurrence after PPV for primary RRD in 42 out of 343 eyes (12.2%) during the follow-up period. Most causes of recurrence (69%) occurred within 6 months of surgery. Multivariate logistic regression analysis showed that a PVR ≥ Grade C (odds ratio [OR]: 4.015; 95% confidence interval [CI] 1.721-9.367; P = 0.001) was a significant predictor for the development of recurrent RRD. Compared with the reattachment group, the recurrence group exhibited a significant decline in best-corrected visual acuity (BCVA) at the last follow-up visit (P = 0.000). Eyes with PVR prior to primary surgery, or at the diagnosis of re-detachment, showed a worse final BCVA.

CONCLUSIONS

Our analysis shows that the predominant risk factor for the recurrence of RRD is a PVR ≥ Grade C. PVR prior to primary surgery, or at the diagnosis of re-detachment, was also shown to limit the recovery of final visual acuity.

Factors Associated With Good Visual Acuity Outcomes After Retinectomy in Eyes With Proliferative Vitreoretinopathy

PURPOSE

To investigate factors associated with good visual acuity (VA) following repair of rhegmatogenous retinal detachments (RD) with proliferative vitreoretinopathy (PVR) undergoing retinectomy.

DESIGN

Interventional, retrospective, case-control study.

METHODS

This single-institution study evaluated patients who underwent retinectomy during repair of RD with PVR from January 1, 2015 to December 31, 2019. A good VA cohort was identified based on a final VA ≥20/70. A 2:1 age-matched and gender-matched poor VA cohort with VA <20/70 was subsequently identified. Metrics compared between the two cohorts included time from primary and recurrent RD diagnosis to surgery, lens status, initial RD size, macula involvement, PVR grade, and size of retinectomy.

RESULTS

A total of 5355 eyes were diagnosed with primary RD during the study period, of which 345 had PVR and underwent retinectomy. The good VA cohort included 62 eyes with a mean final logMAR VA of 0.32 [Snellen 20/42], while the poor VA cohort included 119 eyes with a mean final logMAR VA of 1.54 [Snellen 20/693; P < .0001]. On multivariate analysis, smaller initial RD size (P = .0090), fewer surgeries (P = .0002), shorter time between recurrent RD diagnosis and subsequent surgeries (P = .0006), better preoperative VA (P = .0276), and pseudophakia at final visit (P = .0049) remained significant predictors of good vision.

CONCLUSION

Eyes undergoing retinectomy during repair of RD with PVR can achieve good VA outcomes. The primary modifiable factor associated with better VA was shorter delay between redetachment diagnosis and surgery, particularly in the absence of silicone oil tamponade.

Influence of the scleral indentation technique on the re-detachment rate following retinal detachment surgery

Purpose

The aim of this study was to determine whether the choice of scleral indentation technique during primary rhegmatogenous retinal detachment surgery has an influence on the risk of re-detachment.

Methods

We included retrospectively 154 eyes with a primary rhegmatogenous retinal detachment treated in the Eye Clinic Sulzbach/Saar Germany, who were operated on by two experienced surgeons using the same basic surgical setup. Surgeon A performed an external 360° indentation, shaved the vitreous base using the light pipe cap, and used the operating microscope (opm) for direct visualization. Surgeon B performed an external 360° indentation, shaved the vitreous base using a simple indentor, and used an endoillumination (light pipe) with the opm and a handheld widefield lens for direct visualization.

Results

Comparing both indentation procedures, 15.66% (13/83) of patients operated on by surgeon A and 9.86% (7/71) of patients operated on by surgeon B had a retinal re-detachment within a follow-up period of 6 months (adj. p = 0.64, two-proportion Z-test).

Conclusion

The rate of retinal re-detachment could be influenced by the indentation technique at the end of surgery favoring external indentation and internal visualization with an endoilluminator (chandelier light). We attribute this to the better visualization of the vitreous base facilitated by endoillumination. However, many variables play a role in the development of retinal re-detachment, requiring further studies with a larger number of patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40942-022-00362-8.

What we already know:

Scleral indentation is widely recognized as an important step in rhegmatogenous retinal detachment surgery via pars-plana vitrectomy.

There are several surgical techniques for scleral indentation, however the procedures are neither standardized, nor have they ever been compared to one another to the best of our knowledge.

What this study adds:

This study shows that the rate of retinal re-detachment could be influenced by the indentation technique at the end of surgery favoring external indentation and internal visualization with an endoilluminator (chandelier light).

We attribute this to the better visualization of the vitreous base facilitated by endoillumination.

The Impact of Travel Distance to Delayed Presentation and Follow-up Attendance of Retinal Detachment Cases in Surabaya, Indonesia

Objectives

To assess the delayed presentation of Retinal Detachment (RD), its association from travel distance to the referral hospital (TDH), the period from symptom onset to consultation (SO-C), Proliferative vitreoretinopathy (PVR) severity, and 6 months follow-up attendance (6mo-FA).

Method

A retrospective review based on medical records. Age, sex, initial best-corrected visual acuity (BCVA), TDH, SO-C, PVR type, and 6mo-FA were recorded. Multivariable ordered logistic regression was used to analyze the association between TDH and SO-C, and SO-C and PVR severity. Multivariable logistic regression was used to analyze 6mo-FA according to TDH. Multiple linear regression was used to assess the association between initial BCVA and TDH. Age and sex were included in all multivariable adjustments.

Results

A total of 387 patients had RD with 59.2% predominantly males and the mean age±SD was 46.3±13.9 years. The initial BCVA of less than 3/60 was 81.1%. The averages of SO-C and TDH were 183.5±456 days and 160.9±364 km, respectively. The TDH of more than 120 km distance was significantly associated with longer SO-C (adjusted OR 1.78; CI 95% 1.09-2.92). PVR was noted in 17.6% of patients. The SO-C of 31-60 days was significantly associated with PVR severity (adjusted OR 4.28; CI 95% 1.47-12.51). The TDH of more than 120 km distance was significantly associated with 6mo-FA (adjusted OR 0.46; CI 95% 0.27-0.93).

Conclusions

Long TDH was significantly associated with a longer period from symptom onset to consultation and 6mo-FA. Hence, accessible eye care is essential to refer RD cases in a timely fashion.

Managing PVR in the Era of Small Gauge Surgery

Proliferative vitreoretinopathy (PVR) is the leading cause of failed rhegmatogenous retinal detachment (RRD) surgery. Based upon the presence of clinical features and due to associated underlying risk factors, it is classified into various grades based upon its severity and extent of involvement. Despite excellent skills, flawless techniques, and high-end technology applied in the management of RRD, PVR still occurs in 5–10% of cases. Due to the advancements in wide angle viewing systems, advance vitrectomy machines and fluidics, early identification, use of long-term heavy silicon oil tamponades, high-speed cutters, small-gauge vitrectomies, use of perfluorocarbon liquid (PFCL), and small-gauge forceps and scissors, the success rate in the management of PVR has increased leading to improved anatomical outcomes. However, functional outcomes do not correlate well with improved anatomical outcomes. Various complications occur after RRD repair that are responsible for re-retinal detachment and recurrence of PVR. This article highlights causes, risk factors, classification, grading, diagnosis, and approach to management of PVR and post-PVR surgery complications.

Placental extract suppresses the formation of fibrotic deposits by tumor necrosis factor alpha and transforming growth factor beta-induced epithelial-mesenchymal transition in ARPE-19 cells

Objective

Epithelial–mesenchymal transition (EMT) is involved in the development of proliferative vitreoretinopathy (PVR) and subsequent fibrosis. Previously, we demonstrated that placental extract ameliorates fibrosis in a mouse model of non-alcoholic steatohepatitis. In this study, we evaluated whether placental extract influences EMT and fibrosis through cytokine-induced EMT in the retinal pigment epithelial cells, in vitro.

Results

Placental extract did not inhibit EMT, but it suppressed excessive mesenchymal reactions and the subsequent fibrosis. These results suggest that placental extract effectively ameliorates EMT-associated fibrosis in PVR. This beneficial effect could be partially attributed to the suppression of excessive mesenchymal reactions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-021-05824-0.

SURGICAL FAILURES AFTER PRIMARY SCLERAL BUCKLING FOR RHEGMATOGENOUS RETINAL DETACHMENT: Comparison of Eyes With and Without Proliferative Vitreoretinopathy

PURPOSE

To compare proliferative vitreoretinopathy (PVR)-related surgical failure and non-PVR-associated failure after scleral buckling for primary rhegmatogenous retinal detachment.

METHODS

In this single-center, retrospective, consecutive case series, eyes with surgical failure after scleral buckling for primary rhegmatogenous retinal detachment were identified. Eyes with surgical failure were categorized as PVR-associated and non-PVR-associated failure, and these groups were compared.

RESULTS

Of the 530 scleral buckling procedures performed, 69 were surgical failures (13%), of which 27 of the 530 (5%) were due to PVR and 42 of the 530 (8%) were from non-PVR causes. Patients with PVR-associated failure were more likely to be smokers (P < 0.001), have a delayed presentation after symptoms (P = 0.011), have preoperative vitreous hemorrhage (P = 0.004), and have preoperative PVR (P = 0.002). Multivariate logistic regression models showed that the odds of PVR-associated failure were greater in eyes with preoperative vitreous hemorrhage (odds ratio, 8.2; P = 0.048), preoperative PVR (odds ratio, 22.7; P = 0.023), and among previous smokers (odds ratio, 28.8; P < 0.001). Thirty-two of 69 patients (46%) required one additional surgical intervention, and 37 of the 69 patients (53%) required two or more additional interventions to achieve final reattachment.

CONCLUSION

Proliferative vitreoretinopathy-related surgical failure after primary scleral buckling was 5%. Risk factors for PVR-associated failure parallel those commonly referenced for pars plan vitrectomy, including smoking history, preoperative vitreous hemorrhage, and preoperative PVR.

The impact of COVID-19 pandemic on surgical primary retinal detachments

PURPOSE

To describe the impact of COVID-19 pandemic on the presentation characteristics, timings and surgical decisions for primary rhegmatogenous retinal detachment (RRD).

METHODS

Historical cohort including all patients who presented to the Surgical Retina Section at Centro Hospitalar Universitário do Porto (CHUPorto), over a 2-year period were recruited and divided in 2 groups: pre-COVID and COVID groups. The onset of the COVID-19 pandemic was recorded as starting on March 18, 2020, the same day the first pandemic-related lockdown came to effect in Portugal.

RESULTS

This study enrolled four hundred and forty-nine eyes of 443 patients: 272 in the pre-COVID group and 177 in the COVID one. Of the patients, 63.6% were male and the mean±SD age was 63.0±13.2y (range 13 to 92y). Of the eyes, 55.5% (n = 151) presented with macular detachment in the pre-COVID group compared with 66.9% (n = 119) in the COVID group (odds ratio [OR] 1.62; 95% confidence interval [CI], 1.09-3.86; p=0.016). The time from symptoms onset to hospital admission (p=0.021) and from admission to surgery (p<0.001) was longer in the COVID era. In the COVID period, silicone oil (OR 2.03, 95%CI 1.09-3.79, p=0.025) and C3F8 gas (OR 2.42, 95%CI 1.57-3.71, p<0.001) were used more often. No differences in anatomical success or final visual acuity were found.

CONCLUSIONS

The lockdown due to COVID pandemic affected the epidemiology of RRD. The services must adapt to the novel reality and produce backup plans for similar events. Despite the contingencies, the final results were not different between groups.

The impact of the COVID-19 Pandemic on rhegmatogenous retinal detachment treatment patterns

Backgrounds

To describe changes in rhegmatogenous retinal detachment (RRD) surgical procedures in Beijing during the COVID-19 Pandemic.

Methods

A retrospective cohort of RRD patients was analyzed. Patients were divided into the COVID-19 pandemic group and pre-COVID-19 group according to their presentation. The presurgery characteristics, surgical procedures, and surgery outcomes were collected. The potential factors related to the choice of pars plana vitrectomy (PPV) or scleral buckling (SB) were analyzed using logistic regression. The differences in the procedure choice under specific conditions were compared. Surgery outcomes were compared between the two groups.

Results

In the COVID-19 pandemic group, less patients received SB (27.8, 41.3%, p = 0.02) while more patients received PPV (72.2, 58.6%, p = 0.02); in patients who received SB, fewer patients received subretinal fluid drainage (45.4,75.7%, p = 0.01); in patients who received PPV, fewer patients received phacovitrectomy (7.0, 21.0%, p = 0.02). The choice of PPV was related to older age (1.03, p = 0.005), the presence of RRD with choroidal detachment (RRD-CD) (2.92, p = 0.03), pseudophakia (5.0, p = 0.002), retinal breaks located posterior to the equator (4.87, p < 0.001), macular holes (9.76, p = 0.005), and a presurgery visual acuity (VA) less than 0.02 (0.44, p = 0.03). Fewer phakia patients with retinal breaks located posterior to the equator (1/28, 11/30, p = 0.01) and fewer patients with chronic RRD and subretinal strand (1/9, 9/16, p = 0.03) received SB in the COVID-19 pandemic group. There were more patients with improved VA (55.7, 40.2%, p = 0.03) in the COVID-19 pandemic group. The overall single-surgery retinal attachment rate was similar in the two groups (94.9, 94.5%, p = 0.99).

Conclusions

During the COVID-19 Pandemic, the main reason for the increased number of PPV in RRD treatment was that more complicated cases were presented. However, the surgeons were conservative in procedure choice in specific cases. The adjustments on RRD treatments lead to comparable surgery outcomes.

Time to Unplanned Return to the Operating Room and Associated Risk Factors in Patients With Surgical Retinal Detachment Repair

PURPOSE

To assess the incidence of unplanned return to the operating room (ROR) at ≤45 days or ≥46 days after primary retinal detachment (RD) surgery and correlate ROR with preoperative risk factors and visual outcomes.

DESIGN

Retrospective cohort study.

METHODS

This was a retrospective review of patients with primary RD surgery to assess for unplanned ROR between January 1, 2012 and June 30, 2014, with follow-up of 90 days to 8 years (mean, 1.5 years). We assessed 268 patients receiving 270 primary rhegmatogenous RD surgeries between January 1, 2012 and June 30, 2014 in an academic tertiary referral center.

RESULTS

Of the 270 RD surgeries, 82 were complicated (history of proliferative vitreoretinopathy or trauma-related RDs at presentation) and 188 were uncomplicated (RD unrelated to trauma or proliferative vitreoretinopathy at presentation). The ROR rate for all surgeries was 12.2% (33/270) over the follow-up period, with 51.5% (17/33) having reoperations within 45 days. The complicated detachment group had a ROR rate of 14.6% (12/82) over the follow-up period, and 50% of those (6/12) had reoperations within 45 days. The uncomplicated detachment group had a ROR rate of 11.2% (21/188) over the follow-up period. Of those, 52.4% (11/21) had reoperations within 45 days.

CONCLUSIONS

Given that only 51.5% of all RORs occurred within 45 days, a 45-day ROR surgical quality metric that has been previously used may be of limited value for RD surgery. Factors such as age at presentation, number of retinal breaks, number of detached clock hours, use of silicone oil tamponade for pars plana vitrectomy, history of choroidal detachment, high myopia, ocular trauma, and open globe were associated with increasing risk of ROR. Implementing risk-adjusted metrics may provide a more accurate and useful quality improvement metric for evaluating quality of surgical care in vitreoretinal surgery. Am J Ophthalmol 2021;221:•••-•••. © 2021 Elsevier Inc. All rights reserved.

The impact of the COVID-19 pandemic lockdown on rhegmatogenous retinal detachment services-Experiences from the Tongren eye center in Beijing

Purpose

To investigate the impact on services for rhegmatogenous retinal detachment (RRD) patients during the COVID-19 (2019coronal virus disease) pandemic in one tertiary center in Beijing.

Methods

A retrospective cohort study. Two reviewed consecutive RRD patients cohorts of the same length were treated during two different periods: the COVID-19 pandemic and the pre-COVID-19 group. The characteristics of patients, surgery, anesthesia methods, length of hospital stay, and the latest follow-up were recorded and analyzed.

Results

There were 79 patients in the COVID-19 pandemic group with a 55.9% reduction (179). Compared to patients in the pre-COVID-19, patients in the COVID-19 pandemic had a longer presurgical waiting times (28days, 3days, p<0.001), a higher percentage of patients with presurgical poor (less than 0.02) visual acuity (55.7%, 32.4%, p = 0.009), and a higher percentage of patients with presurgical choroidal detachment (34.2%, 19.6%, p = 0.01). There was no significant difference in the severity of presurgical proliferative vitreoretinopathy between the two groups (p = 0.64). Surgeries on pathological myopia patients with macular hole retinal detachment were postponed in the COVID-19 pandemic. There was a lower percentage of scleral buckling (27.8%, 41.3%, p = 0.02) and a lower rate of subretinal fluid drainage (45.4%, 75.7%, p = 0.01) in the COVID-19 pandemic. There was no significant difference in either postoperative visual acuity (p = 0.73) or the rate of single-surgery retinal attachment (p = 1) between the two groups. Patients in the COVID-19 pandemic had a shorter length of hospital stay (3hours, 35 hours, p<0.001), and a lower percentage of patients received general anesthesia (48.1%, 83.2%, p<0.001). None was infected with COVID-19 disease during the pandemic.

Conclusion

The COVID-19 pandemic lockdown caused prolonged presurgical waiting times, shorter hospital stays, less general anesthesia, and a significant reduction of RRD surgeries. The RD were more complicated, the surgeons were more conservative on procedures and patients selection, while the surgery outcomes were comparable.

Retinal detachment during COVID-19 era: a review of challenges and solutions

Background

Since the beginning of the Coronavirus disease 2019 (COVID-19) pandemic, there have been obstacles in the proper diagnosis and management of many diseases. We evaluated the changes in retinal detachment (RD) presentation and surgery during the COVID-19 pandemic and propose solutions to minimize the detrimental effects of lockdown on RD diagnosis.

Materials and methods

PubMed, Embase, Scopus, Web of Science, and Google Scholar were searched for relevant articles with the keywords “Retinal detachment” AND “Coronavirus OR COVID-19 OR SARS OR MERS.”

Results

The COVID-19 lockdown was associated a 53–66% reduction in RD presentation. The decrease in the rate of macula-on RD, the increase in the mean duration of symptoms, and the rise in the number of patients with proliferative vitreoretinopathy were all suggestive of a delayed presentation of RD. Moreover, a drop of 56–62% in RD repair surgeries was observed. However, the most frequently performed ophthalmic surgery changed from cataract surgery in April 2019 to RD repair in April 2020. Using phacovitrectomy instead of vitrectomy alone can reduce the number of operations in ophthalmology centers, decrease the use of personal protective equipment by 50%, and cut costs per patient by 17–20%. Also, developing a well-organized telemedicine system can decrease unnecessary visits and delayed presentations.

Conclusion

Delay in RD presentation and surgery is associated with a poorer prognosis. Optimizing the guidelines of RD management and developing a well-organized telemedicine system can minimize the impact of lockdown on RD management.

The risk factors of the progression of rhegmatogenous retinal detachment on patients with the fourteen-day quarantine in the early period of COVID-19 outbreak

Backgrounds

The COVID-19 Pandemic has a great impact on hospitals and patients. The 14-day quarantine caused surgery of rhegmatogenous retinal detachment (RRD) postponed. We aimed to explore the risk factors of RRD progression in a group of patients whose surgery was postponed during the top-level emergency response of COVID-19.

Methods

A retrospective case series. Medical records of all consecutive patients with a diagnosis of RRD who underwent a surgical treatment at Beijing Tongren Hospital’s retina service from February 16, 2020, to April 30, 2020 have been reviewed retrospectively. Medical history, symptoms, and clinical signs of progression of RRD were recorded. RRD progression was defined as the presence of either choroidal detachment or proliferative vitreoretinopathy (PVR) progression during the quarantine period. Risk factors were analyzed using the Cox proportional hazards model, survival analysis, and logistic regression.

Results

Seventy-nine eyes of 79 patients met the inclusion criteria and were included in the study. The median time from the patients’ presentation at the clinic to admission for surgery was 14 days (3–61 days). There were 70 cases (88.6%) who did not present to the hospital within 1 week of the onset of visual symptoms. There were 69 (87.3%) macular-off cases at the presentation and 27 (34.2%) cases combined with choroidal detachment. There were 49 (62.0%) cases with PVR B, 22 (27.8%) cases with PVR C, 4 (5.1%) cases with PVR D, and 4 (5.1%) cases with anterior PVR. After the 14-day quarantine, 21 (26.6%) cases showed RRD progression, and 9 cases showed RRD regression at the time of surgery. Neither the time of onset of the visual symptom (p = 0.46) nor the time between presentation and admission (p = 0.31) was significantly different between the patients with RRD progression and patients without RRD progression. The combination of choroidal detachment (3.07, 1.68-5.60, p<0.001) and retinal breaks located posterior to the equator (3.79, 1.21-11.80, p=0.02) were factors related to the progression of RRD.

Conclusions

In our study during the COVID-19 outbreak, the RRD progression risk factors included a combination of choroidal detachment and retinal breaks posterior to the equator. Ophthalmologists should schedule the surgeries for RRD patients with these signs as soon as possible.

Hirudo (Leech) for proliferative vitreous retinopathy: A protocol for systemic review and meta-analysis

INTRODUCTION

Proliferative vitreous retinopathy (PVR) is characterized by proliferation of cells and contraction of membranes on either the retinal surface or in the vitreous cavity, which leads to retinal detachment and visual impairment. PVR is commonly seen in patients with rhegmatogenous retinal detachment and diabetic retinopathy, which seriously affects the patient's work and life. Previous studies indicated that Hirudo (Leech) or compound prescription containing Hirudo (Leech) for treatment of PVR would be effective. However, due to the lack of evidence, there are no specific methods or suggestions, so it is necessary to carry out systematic evaluations on Hirudo (Leech) for PVR and provide effective evidence for further research.

METHODS AND ANALYSIS

The following 8 databases will be searched: Cochrane Central Register of Controlled Trials, PubMed, MEDLINE, EMBASE, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, VIP Database, and Wanfang Database. All randomized controlled trials in English or Chinese related to Hirudo (Leech) for PVR will be included. Outcomes will include change in Vitreous opacity, Vision changes, production of the anterior macular membrane, and retinal detachment again. The incidence of adverse events will be assessed for safety evaluation. Study inclusion, data extraction and quality assessment will be performed independently by 2 reviewers. Assessment of risk of bias and data synthesis will be performed using Review Manager V.5.3.

RESULTS

In this systematic review and meta-analysis, we will synthesize the studies to assess the safety and efficacy of Hirudo (Leech) for PVR.

CONCLUSION

The summary of our study will clarify whether Hirudo (Leech) therapy could be an efficient and safe method for PVR, which can further guide the promotion and application of it.

OPEN SCIENCE FRAMEWORK OSF REGISTRATION NUMBER

10.17605/OSF.IO/FP7VG (https://osf.io/fp7vg).

[Proliferative vitreoretinopathy process-To heal or not to heal]

BACKGROUND

Proliferative vitreoretinopathy (PVR) is still an unsolved problem after half a century of research.

METHODS

This article provides a review of mechanisms leading to PVR in the context of wound healing research.

RESULTS

Wound healing is a physiological repair process that occurs in a similar way in all organs and may end in scar formation. The development of PVR is based on this wound healing mechanism. The localization and structures involved lead to specific characteristics and consequences. Up to now the pharmacotherapeutic strategies were not sufficiently effective. The growing understanding of the mechanisms of scar-free fetal wound healing, could however lead to a solution of the PVR problem.

CONCLUSION

The PVR is a physiological process with a pathological result. The complex steps involved in vitreoretinal wound healing are well understood. There is currently no therapeutic approach neither in ophthalmology nor in other medical disciplines that is able to restore the original function and structure of the involved tissue or organ but there is hope that this can succeed in the future.

Salinomycin inhibits proliferative vitreoretinopathy formation in a mouse model

Proliferative vitreoretinopathy (PVR) is a progressive disease that develops in a subset of patients who undergo surgery for retinal detachment repair, and results in significant vision loss. PVR is characterized by the migration of retinal pigment epithelial (RPE) cells into the vitreous cavity, where they undergo epithelial-to-mesenchymal transition and form contractile membranes within the vitreous and along the retina, resulting in recurrent retinal detachments. Currently, surgical intervention is the only treatment for PVR and there are no pharmacological agents that effectively inhibit or prevent PVR formation. Here, we show that a single intravitreal injection of the polyether ionophore salinomycin (SNC) effectively inhibits the formation of PVR in a mouse model with no evidence of retinal toxicity. After 4 weeks, fundus photography and optical coherence tomography (OCT) demonstrated development of mean PVR grade of 3.5 (SD: 1.3) in mouse eyes injected with RPE cells/DMSO (vehicle), compared to mean PVR grade of 1.6 (SD: 1.3) in eyes injected with RPE cells/SNC (p = 0.001). Additionally, immunohistochemistry analysis showed RPE cells/SNC treatment reduced both fibrotic (αSMA, FN1, Vim) and inflammatory (GFAP, CD3, CD20) markers compared to control RPE cells/DMSO treatment. Finally, qPCR analysis confirmed that Tgfβ, Tnfα, Mcp1 (inflammatory/cytokine markers), and Fn1, Col1a1 and Acta2 (fibrotic markers) were significantly attenuated in the RPE cells/SNC group compared to RPE/DMSO control. These results suggest that SNC is a potential pharmacologic agent for the prevention of PVR in humans and warrants further investigation.

Predictive modeling of proliferative vitreoretinopathy using automated machine learning by ophthalmologists without coding experience

We aimed to assess the feasibility of machine learning (ML) algorithm design to predict proliferative vitreoretinopathy (PVR) by ophthalmologists without coding experience using automated ML (AutoML). The study was a retrospective cohort study of 506 eyes who underwent pars plana vitrectomy for rhegmatogenous retinal detachment (RRD) by a single surgeon at a tertiary-care hospital between 2012 and 2019. Two ophthalmologists without coding experience used an interactive application in MATLAB to build and evaluate ML algorithms for the prediction of postoperative PVR using clinical data from the electronic health records. The clinical features associated with postoperative PVR were determined by univariate feature selection. The area under the curve (AUC) for predicting postoperative PVR was better for models that included pre-existing PVR as an input. The quadratic support vector machine (SVM) model built using all selected clinical features had an AUC of 0.90, a sensitivity of 63.0%, and a specificity of 97.8%. An optimized Naïve Bayes algorithm that did not include pre-existing PVR as an input feature had an AUC of 0.81, a sensitivity of 54.3%, and a specificity of 92.4%. In conclusion, the development of ML models for the prediction of PVR by ophthalmologists without coding experience is feasible. Input from a data scientist might still be needed to tackle class imbalance-a common challenge in ML classification using real-world clinical data.

PREDICTIVE FACTORS FOR PROLIFERATIVE VITREORETINOPATHY FORMATION AFTER UNCOMPLICATED PRIMARY RETINAL DETACHMENT REPAIR

PURPOSE

To determine predictive factors of proliferative vitreoretinopathy (PVR) formation after uncomplicated primary retinal detachment repair.

METHODS

Retrospective, single-center, case-control study of 74 consecutive patients with (37 eyes) and without (37 eyes) PVR formation after undergoing uncomplicated primary surgery for retinal detachment repair. Logistic regression was used to assess factors associated with PVR formation.

RESULTS

Retinal detachment involving the macula was 4.2 times (adjusted odds ratio; 95% confidence interval, 1.4-12.9; P = 0.0119) more likely to have PVR formation compared with those without. Patients who were current or former smokers were 3.6 times (adjusted odds ratio; 95% confidence interval, 1.1-11.7; P = 0.0352) more likely to have PVR formation compared with nonsmokers. Compared with 25-gauge (g) vitrectomy, larger gauge vitrectomy (20 g or 23 g) was 3.6 times (adjusted odds ratio; 95% confidence interval, 1.2-11.3; P = 0.0276) more likely to have PVR formation. Duration of retinal detachment symptoms, high myopia, lens status, lattice degeneration, location of retinal break, number of retinal breaks, and surgical technique (e.g., scleral buckle with or without vitrectomy versus vitrectomy alone) were not found to be predictive of PVR formation.

CONCLUSION

Cigarette smoking and macular involvement are significant risk factors predictive of PVR formation after uncomplicated primary retinal detachment repair.

Clinical characteristics and prognosis of Total Rhegmatogenous retinal detachment: a matched case-control study

Background

Although many studies have reported clinical features, surgical outcomes of rhegmatogenous retinal detachment (RRD), studies focusing on total RRD are rare. In this study, we investigate the clinical characteristics, risk factors, and prognosis of total RRD.

Methods

A retrospective chart review was performed on cases of 44 total RRD and an age- and sex-matched 88 partial RRD. Two groups were compared for clinical characteristics, risk factors, and prognosis.

Results

The prevalence of total RRD in all cases of retinal detachment was 4.4%. Pseudophakic eye, ocular trauma, and proliferative vitreoretinopathy (PVR) were significantly associated with a risk of total RRD (P = .002, P = .003, and P < .001, respectively). In the total RRD group, retinal breaks were located in both superior and inferior parts of the retina, and macular holes and giant retinal tears were frequently found. The best-corrected visual acuity (log MAR) before surgery and final best-corrected visual acuity after surgery were 2.23 ± 0.45 and 1.88 ± 0.96, which was significantly poorer than in the partial RRD group (P < .001). The success rate after primary surgery was 75.0% in the total RRD group, which was significantly lower than partial RRD group (P < .001). Old age, pseudophakic eye, and macular hole as the type of retinal break were highly associated with low success rate. (P = .010, P = .0500, and P = .002).

Conclusions

Patients with total RRD had higher recurrence rate and poorer visual outcome after surgery than patients with focal RRD. Old age, pseudophakic eye, and presence of macular hole were important risk factors for recurrence after total RRD repair. Additional surgical procedures should be considered to combine with vitrectomy to achieve better surgical outcomes in these patients.

A Mouse Model of Proliferative Vitreoretinopathy Induced by Intravitreal Injection of Gas and RPE Cells

Purpose

Develop a reproducible proliferative vitreoretinopathy (PVR) mouse model that mimics human PVR pathology.

Methods

Mice received intravitreal injections of SF6 gas, followed by retinal pigment epithelial cells 1 week later. PVR progression was monitored using fundus photography and optical coherence tomography imaging, and histologic analysis of the retina as an endpoint. We developed a PVR grading scheme tailored for this model.

Results

We report that mice that received gas before retinal pigment epithelial injection developed more severe PVR. In the 1 × 104 retinal pigment epithelial cell group, after 1 week, 0 of 11 mice in the no gas group developed grade 4 or greater PVR compared with 5 of 13 mice in the SF6 gas group (P = 0.02); after 4 weeks, 3 of 11 mice in the no gas group developed grade 5 or greater PVR compared with 11 of 14 mice in the SF6 gas group (P = 0.01). We were able to visualize contractile membranes both on the retinal surface as well as within the vitreous of PVR eyes, and demonstrated through immunohistochemical staining that these membranes expressed fibrotic markers alpha smooth muscle actin, vimentin, and fibronectin, as well as other markers known to be found in human PVR membranes.

Conclusions

This mouse PVR model is reproducible and mimics aspects of PVR pathology reported in the rabbit PVR model and human PVR. The major advantage is the ability to study PVR development in different genetic backgrounds to further elucidate aspects of PVR pathogenesis. Additionally, large-scale experiments for testing pharmacologic agents to treat and prevent PVR progression is more feasible compared with other animal models.

Translational Relevance

This model will provide a platform for screening potential drug therapies to treat and prevent PVR, as well as elucidate different molecular pathways involved in PVR pathogenesis.

Preoperative, Intraoperative and Postoperative Corticosteroid Use as an Adjunctive Treatment for Rhegmatogenous Retinal Detachment

The treatment for rhegmatogenous retinal detachment (RRD) is surgery, including pars plana vitrectomy (PPV) and scleral buckling (SB). Despite surgical advances, degeneration of the photoreceptors and post-operative complications, such as proliferative vitreoretinopathy (PVR), often occurs as the result of inflammation, preventing complete visual recovery or causing RRD recurrence. There is increasing evidence that in the presence of RRD, the activation of inflammatory processes occurs and the surgery itself induces an inflammatory response. This comprehensive review focuses on the use of different formulations of corticosteroids (CCS), as an adjunctive treatment to surgery, either PPV or SB, for RRD repair. The purpose was to review the efficacy and safety of CCS in improving functional and anatomical outcomes and in preventing postoperative complications. This review is organized according to the timing of CCS administration: preoperative, intraoperative, and postoperative. The evidence reviewed supported the role of the pre-operative use of CCS in the treatment of combined RRD and choroidal detachment (CD), reducing CD height. No solid consensus exists on intraoperative and postoperative use of CCS to treat and prevent postoperative complications. However, a large randomized clinical trial including more than 200 eyes suggested that oral prednisone after surgery decreases the rate of postoperative grade B PVR.

MicroRNAs in the Vitreous Humor of Patients with Retinal Detachment and a Different Grading of Proliferative Vitreoretinopathy: A Pilot Study

Purpose

Although the expression of microRNAs (miRNAs) in retinal pigment epithelial (RPE) cells undergoing epithelial-mesenchymal transition (EMT) is involved in the pathogenesis of proliferative vitreoretinopathy (PVR), its expression in the vitreous of patients with primary retinal detachment (RD) and different PVR grading has not yet been investigated. We assessed the expression of miRNAs in the vitreous humor (VH) of patients diagnosed with RD and different grading of PVR.

Methods

The VH was extracted from the core of the vitreous chamber in patients who had undergone standard vitrectomy for primary RD. RNA was extracted and TaqMan Low-Density Arrays (TLDAs) were used for miRNA profiling that was performed by single TaqMan assays. A gene ontology (GO) analysis was performed on the differentially expressed miRNAs.

Results

A total of 15 eyes with RD, 3 eyes for each grade of PVR (A, B, C, and D) and 3 from unaffected individuals, were enrolled in this prospective comparative study. Twenty miRNAs were altered in the comparison among pathological groups. Interestingly, the expression of miR-143-3p, miR-224-5p, miR-361-5p, miR-452-5p, miR-486-3p, and miR-891a-5p increased with the worsening of PVR grading. We also identified 34 miRNAs showing differential expression in PVR compared to control vitreous samples. GO analysis showed that the deregulated miRNAs participate in processes previously associated with PVR pathogenesis.

Conclusions

The present pilot study suggested that dysregulated vitreal miRNAs may be considered as a biomarker of PVR and associated with the PVR-related complications in patients with RD.

Translational Relevance

The correlation between vitreal miRNAs and the pathological phenotypes are essential to identify the novel miRNA-based mechanisms underlying the PVR disease that would improve the diagnosis and treatment of the condition.

Pars plana vitrectomy combined with scleral buckle versus pars plana vitrectomy for giant retinal tear

BACKGROUND

A giant retinal tear (GRT) is a full-thickness neurosensory retinal break extending for 90° or more in the presence of a posterior vitreous detachment.

OBJECTIVES

To evaluate the effectiveness and safety of pars plana vitrectomy combined with scleral buckle versus pars plana vitrectomy alone for eyes with giant retinal tear.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 8), which contains the Cochrane Eyes and Vision Trials Register; Ovid MEDLINE; Embase.com; PubMed; Latin American and Caribbean Literature on Health Sciences (LILACS); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in our electronic search. We last searched the electronic databases on 16 August 2018.

SELECTION CRITERIA

We included only randomized controlled trials (RCTs) comparing pars plana vitrectomy combined with scleral buckle versus pars plana vitrectomy alone for giant retinal tear regardless of age, gender, lens status (e.g. phakic or pseudophakic eyes) of the affected eye(s), or etiology of GRT among participants enrolled in these trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed titles and abstracts, then full-text articles, using Covidence. Any differences in classification between the two review authors were resolved through discussion. Two review authors independently abstracted data and assessed risk of bias of included trials.

MAIN RESULTS

We found two RCTs in abstract format (105 participants randomized). Neither RCT was published in full. Based on the data presented in the abstracts, scleral buckling might be beneficial (relative risk of re-attachement ranged from 3.0 to 4.4), but the findings are inconclusive due to a lack of peer reviewed publication and insufficient information for assessing risk of bias.

AUTHORS' CONCLUSIONS

We found no conclusive evidence from RCTs on which to base clinical recommendations for scleral buckle combined with pars plana vitrectomy for giant retinal tear. RCTs are clearly needed to address this evidence gap. Such trials should be randomized, and patients should be classified by giant retinal tear characteristics (extension (90º, 90º to 180º, > 180º), location (oral, anterior, posterior to equator)), proliferative vitreoretinopathy stage, and endotamponade. Analysis should include both short-term (three months and six months) and long-term (one year to two years) outcomes for primary retinal reattachment, mean change in best corrected visual acuity, study eyes that required second surgery for retinal reattachment, and adverse events such as elevation of intraocular pressure above 21 mmHg, choroidal detachment, cystoid macular edema, macular pucker, proliferative vitreoretinopathy, and progression of cataract in initially phakic eyes.

The polyether ionophore salinomycin targets multiple cellular pathways to block proliferative vitreoretinopathy pathology

Proliferative vitreoretinopathy (PVR) is characterized by membranes that form in the vitreous cavity and on both surfaces of the retina, which results in the formation of tractional membranes that can cause retinal detachment and intrinsic fibrosis of the retina, leading to retina foreshortening. Currently, there are no pharmacologic therapies that are effective in inhibiting or preventing PVR formation. One of the key aspects of PVR pathogenesis is retinal pigment epithelial (RPE) cell epithelial mesenchymal transition (EMT). Here we show that the polyether ionophore compound salinomycin (SNC) effectively inhibits TGFβ-induced EMT of RPE cells. SNC blocks the activation of TGFβ-induced downstream targets alpha smooth muscle actin (αSMA) and collagen 1 (Col1A1). Additionally, SNC inhibits TGFβ-induced RPE cell migration and contraction. We show that SNC functions to inhibit RPE EMT by targeting both the pTAK1/p38 and Smad2 signaling pathways upon TGFβ stimulation. Additionally, SNC is able to inhibit αSMA and Col1A1 expression in RPE cells that have already undergone TGFβ-induced EMT. Together, these results suggest that SNC could be an effective therapeutic compound in both the prevention and treatment of PVR.

Metabolomics in the study of retinal health and disease

Metabolomics is the qualitative and quantitative assessment of the metabolites (small molecules < 1.5 kDa) in body fluids. The metabolites are the downstream of the genetic transcription and translation processes and also downstream of the interactions with environmental exposures; thus, they are thought to closely relate to the phenotype, especially for multifactorial diseases. In the last decade, metabolomics has been increasingly used to identify biomarkers in disease, and it is currently recognized as a very powerful tool with great potential for clinical translation. The metabolome and the associated pathways also help improve our understanding of the pathophysiology and mechanisms of disease. While there has been increasing interest and research in metabolomics of the eye, the application of metabolomics to retinal diseases has been limited, even though these are leading causes of blindness. In this manuscript, we perform a comprehensive summary of the tools and knowledge required to perform a metabolomics study, and we highlight essential statistical methods for rigorous study design and data analysis. We review available protocols, summarize the best approaches, and address the current unmet need for information on collection and processing of tissues and biofluids that can be used for metabolomics of retinal diseases. Additionally, we critically analyze recent work in this field, both in animal models and in human clinical disease, including diabetic retinopathy and age-related macular degeneration. Finally, we identify opportunities for future research applying metabolomics to improve our current assessment and understanding of mechanisms of vitreoretinal diseases, and to hence improve patient assessment and care.

Determining the effect of low-dose isotretinoin on proliferative vitreoretinopathy: the DELIVER trial

PURPOSE

To examine the effect of low-dose, oral isotretinoin in lowering the risk of proliferative vitreoretinopathy (PVR) following rhegmatogenous retinal detachment (RRD) repair.

METHODS

Prospective, open label, dual-cohort study with pathology-matched historical controls. The prospective experimental arms included two cohorts, composed of 51 eyes with recurrent PVR-related RRD and 58 eyes with primary RRD associated with high-risk features for developing PVR. Eyes in the experimental arms received 20 mg of isotretinoin by mouth once daily for 12 weeks starting the day after surgical repair. The primary outcome measure was single surgery anatomical success rate at 3 months following the study surgery.

RESULTS

The single surgery anatomic success rate was 78.4% versus 70.0% (p=0.358) in eyes with recurrent PVR-related retinal detachment exposed to isotretinoin versus historical controls, respectively. In eyes with RRD at high risk for developing PVR, the single surgery success rate was 84.5% versus 61.1% (p=0.005) for eyes exposed to isotretinoin versus historical controls, respectively. For eyes enrolled in the experimental arms, the most common isotretinoin-related side effects were dry skin/mucus membranes in 106 patients (97.2%), abnormal sleep/dreams in 4 patients (3.7%) and fatigue in 3 patients (2.8%).

CONCLUSION

The management and prevention of PVR is challenging and complex. At the dose and duration given in this study, oral istotretinoin may reduce the risk of PVR-associated recurrent retinal detachment in eyes with primary RRD at high risk of developing PVR.

Personalized Proteomics in Proliferative Vitreoretinopathy Implicate Hematopoietic Cell Recruitment and mTOR as a Therapeutic Target

PURPOSE

To profile vitreous cytokine expression of proliferative vitreoretinopathy (PVR) patients.

DESIGN

Case-control study.

METHODS

Liquid biopsies were collected from 2 groups: control subjects (n = 3) undergoing pars plana vitrectomy to remove an epiretinal membrane (ERM), and test subjects (n = 7) with varying degrees of PVR. A high-throughput cytokine screen measured expression of 200 cytokines. Cytokine expression patterns were prospectively validated in separate cohorts of control patients and those with PVR-A, PVR-B, and PVR-C (n = 10 for each group). Expression changes were evaluated by analysis of variance (significant P value < .05), hierarchical cluster algorithm, and pathway analysis, to identify candidate pathways for prospective studies.

RESULTS

In PVR vitreous, 29 cytokines were upregulated compared to controls. Early PVR vitreous showed upregulation of T-cell markers, profibrotic cytokines, and cytokines downstream of mTOR activation (IL-2, IL-6, and IL-13), whereas in late PVR vitreous, cytokines driving monocyte responses and stem-cell recruitment (SDF-1) prevailed. Prospective validation confirmed the differential expression of specific cytokines from PVR-A to C.

CONCLUSIONS

Early PVR is characterized by activation of T cells and mTOR signaling, whereas advanced PVR is characterized by a chronic monocyte response. PVR might be treated by rational repositioning of existing drugs that target mTOR and IL-6. Our analysis demonstrates that successful therapeutic intervention will be highly dependent on the specific therapeutic target and the stage of PVR. This study provides insights into cytokines that will serve as biomarkers and therapeutic targets. These biomarkers will help design clinical trials that intervene at appropriate times.

Crocetin inhibits the proliferation, migration and TGF-β2-induced epithelial-mesenchymal transition of retinal pigment epithelial cells

Retinal pigment epithelial (RPE) cells, the major cell type in the fibrotic membrane of proliferative vitreoretinopathy, display enhanced proliferative and migratory capacities and epithelial-mesenchymal transition (EMT). In this study, we investigated the potential impact of crocetin on the proliferation, migration and EMT of cultured ARPE-19 cells. The cells were treated with crocetin alone or in combination with transforming growth factor-β₂ (TGF-β₂). Cell proliferation was examined using the CCK-8 assay. Cell cycle distribution was analyzed by flow cytometry after propidium iodide staining. The expression levels of proliferating cell nuclear antigen (PCNA), p21 and p53 were examined by Western blot analysis. Cell migration was assessed by in vitro scratch and Transwell assays. Real-time PCR, Western blotting and immunofluorescence were used to assess EMT features. Treatment of ARPE-19 cells with crocetin (50-200μM) significantly inhibited their proliferation and migration in a concentration- and time-dependent manner. Crocetin induced G1 arrest, reduced PCNA protein expression and increased the p21 and p53 accumulation in ARPE-19 cells. Crocetin inhibited TGF-β₂-induced EMT in ARPE-19 cells by maintaining the expression of E-cadherin and ZO-1 and by reducing the expression of vimentin and α-SMA through the suppression of phosphorylation of p38. These results indicate that crocetin is an effective inhibitor of the proliferation, migration and TGF-β₂-mediated EMT of ARPE-19 cells.

Role of macrophage migration inhibitory factor (MIF) in the effects of oxidative stress on human retinal pigment epithelial cells

Proliferative vitreoretinopathy (PVR) is the major cause of treatment failure in individuals who undergo surgery for retinal detachment. The epithelial-mesenchymal transition (EMT) in retinal pigment epithelium (RPE) cells contributes to the pathogenesis of PVR. Oxidative stress is thought to play a role in the progression of retinal diseases including PVR. We have now examined the effects of oxidative stress on the EMT and related processes in the human RPE cell line. We found that H₂ O₂ induced the contraction of RPE cells in a three-dimensional collagen gel. Analysis of a cytokine array revealed that H₂ O₂ specifically increased the release of macrophage migration inhibitory factor (MIF) from RPE cells. Reverse transcription-polymerase chain reaction and immunoblot analyses showed that H₂ O₂ increased the expression of MIF in RPE cells. Immunoblot and immunofluorescence analyses revealed that H₂ O₂ upregulated the expression of α-SMA and vimentin and downregulated that of ZO-1 and N-cadherin. Consistent with these observations, the transepithelial electrical resistance of cell was reduced by exposure to H₂ O₂ . The effects of oxidative stress on EMT-related and junctional protein expression as well as on transepithelial electrical resistance were inhibited by antibodies to MIF, but they were not mimicked by treatment with recombinant MIF. Finally, analysis with a profiling array for mitogen-activated protein kinase signalling revealed that H₂ O₂ specifically induced the phosphorylation of p38 mitogen-activated protein kinase. Our results thus suggest that MIF may play a role in induction of the EMT and related processes by oxidative stress in RPE cells and that it might thereby contribute to the pathogenesis of PVR. Proliferative vitreoretinopathy is a major complication of rhegmatogenous retinal detachment, and both oxidative stress and induction of the EMT in RPE cells are thought to contribute to the pathogenesis of this condition. We have now examined the effects of oxidative stress on the EMT and related processes in the human RPE cell line ARPE19. Our results thus implicate MIF in induction of the EMT and related processes by oxidative stress in RPE cells and the regulated expression of EMT markers. They further suggest that MIF may play an important role in the pathogenesis of PVR.

Exclusive Use of Air as Gas Tamponade in Rhegmatogenous Retinal Detachment

Purpose

To investigate outcomes of vitrectomy for rhegmatogenous retinal detachment (RRD) using air exclusively as the gas tamponade.

Methods

This retrospective, interventional, consecutive case series involved reviewing medical records of patients that underwent vitrectomy and gas tamponade for RRD between January 2013 and December 2015. Patients whose eyes were treated exclusively with air tamponade since July 2014 were assigned to the air group, while those treated with heterogeneous gas agents before June 2014 were assigned to the control group. The primary outcome was the primary reattachment rate. Best-corrected visual acuity (BCVA) and duration to detect redetachments were assigned as the secondary outcomes.

Results

The air group and the control group included 71 and 72 eyes, respectively. The primary reattachment rate was 94.4% in the air group and there was no significant difference with 94.4% in the control group (p = 0.951). BCVA was significantly better in the air group at 1 month (p = 0.021) but not at 3 months postoperatively (p = 0.561). Redetachments were recognized earlier in the air group (9.3 ± 0.5 days) compared with those in the control group (21.3 ± 7.4 days) (p = 0.041).

Conclusions

In cases of simple RRD with sufficient removal of subretinal fluid, air could be considered for use as gas tamponade. This trial is registered with KCT0002358.

Biological Involvement of MicroRNAs in Proliferative Vitreoretinopathy

Even with a high surgical success rate for retinal detachment and proliferative vitreoretinopathy (PVR) supported by the robust improvement in vitrectomy surgery and its related devices, certain questions still remain for the pathogenesis and treatment of PVR. One of the important biological events in PVR is epithelial–mesenchymal transition (EMT) of the retinal pigment epithelial (RPE) cells. MicroRNAs are noncoding, small, single-strand RNAs that posttranscriptionally regulate gene expression and have essential roles in homeostasis and pathogenesis in many diseases. Recently, microRNAs also had a critical role in EMT in many tissues and cells. One main purpose of this brief review is to describe the knowledge obtained from microRNA research, especially concerning vitreoretinal diseases. In addition, the potential role of microRNAs in prevention of PVR by regulating EMT in RPE cells is described. Understanding microRNA involvement in PVR could be helpful for developing new biological markers or therapeutic targets and reducing the rate of visual disability due to PVR.

Rapid monocyte infiltration following retinal detachment is dependent on non-canonical IL6 signaling through gp130

BACKGROUND

Retinal detachment (RD) can lead to proliferative vitreoretinopathy (PVR), a leading cause of intractable vision loss. PVR is associated with a cytokine storm involving common proinflammatory molecules like IL6, but little is known about the source and downstream signaling of IL6 and the consequences for the retina. Here, we investigated the early immune response and resultant cytokine signaling following RD in mice.

METHODS

RD was induced in C57BL/6 J and IL6 knockout mice, and the resulting inflammatory response was examined using immunohistochemistry and flow cytometry. Cytokines and signaling proteins of vitreous and retinas were quantified by multiple cytokine arrays and Western blotting. To attempt to block IL6 signaling, a neutralizing antibody of IL6 receptor α (IL6Rα) or IL6 receptor β (gp-130) was injected intravitreally immediately after RD.

RESULTS

Within one day of RD, bone marrow-derived Cd11b + monocytes had extravasated from the vasculature and lined the vitreal surface of the retina, while the microglia, the resident macrophages of the retina, were relatively unperturbed. Cytokine arrays and Western blot analysis revealed that this sterile inflammation did not cause activation of IL6 signaling in the neurosensory retina, but rather only in the vitreous and aqueous humor. Monocyte infiltration was inhibited by blocking gp130, but not by IL6 knockout or IL6Rα blockade.

CONCLUSIONS

Together, our results demonstrate that monocytes are the primary immune cell mediating the cytokine storm following RD, and that any resulting retinal damage is unlikely to be a direct result of retinal IL6 signaling, but rather gp130-mediated signaling in the monocytes themselves. These results suggest that RD should be treated immediately, and that gp130-directed therapies may prevent PVR and promote retinal healing.

Validity of aqueous flare measurement in predicting proliferative vitreoretinopathy in patients with rhegmatogenous retinal detachment

PURPOSE

To investigate aqueous flare as a preoperative predictor for later proliferative vitreoretinopathy (PVR) development in patients with rhegmatogenous retinal detachment (RD) and to determine the validity of this measurement in patients at low clinical risk for postoperative PVR.

METHODS

This study included 100 eyes of 100 patients who underwent surgery for primary RD. Aqueous flare was determined preoperatively with a laser flare-cell meter (Kowa FM-500, Kowa Company Ltd, Tokyo, Japan). Patients were followed for at least 6 months postoperatively. Failures related to PVR were recorded for statistical analysis.

RESULTS

Twenty eyes (20%) developed PVR postoperatively. Preoperative flare values in these eyes were significantly higher than in eyes with no redetachment (48.12 ± 61.24 versus 17.74 ± 29.63 photon counts per millisecond (pc/ms), p = 0.002). The odds ratio for PVR development with flare values >15 pc/ms was 12.3 (p < 0.0001, 95% confidence interval, 3.54-42.59). Of 54 eyes at low clinical risk for postoperative PVR, five developed PVR postoperatively. Flare values were significantly higher in these eyes (25.30 ± 7.10 pc/ms) than in eyes with no redetachment (12.44 ± 10.16 pc/ms, p = 0.008). Using logistic regression, the odds ratio of PVR redetachment risk increased by the factor 1.078 per 1 pc/ms of flare value (95% CI, 1.01-1.15).

CONCLUSION

Preoperative aqueous flare is a strong predictive factor for PVR redetachment. The laser flare-cell meter provides a fast and safe tool to accurately identify patients at risk for postoperative PVR, especially when clinical examination did not predict this risk.

Inhibition of Proliferation and Epithelial Mesenchymal Transition in Retinal Pigment Epithelial Cells by Heavy Chain-Hyaluronan/Pentraxin 3

Proliferative vitreoretinopathy (PVR) is mediated by proliferation and epithelial mesenchymal transition (EMT) of retinal pigment epithelium (RPE). Because heavy chain-hyaluronic acid/pentraxin 3 (HC-HA/PTX3) purified from human amniotic membrane exerts anti-inflammatory and anti-scarring actions, we hypothesized that HC-HA/PTX3 could inhibit these PVR-related processes in vitro. In this study, we first optimized an ARPE-19 cell culture model to mimic PVR by defining cell density, growth factors, and cultivation time. Using this low cell density culture model and HA as a control, we tested effects of HC-HA/PTX3 on the cell viability (cytotoxicity), proliferation (EGF + FGF-2) and EMT (TGF-β1). Furthermore, we determined effects of HC-HA/PTX3 on cell migration (EGF + FGF-2 + TGF-β1) and collagen gel contraction (TGF-β1). We found both HA and HC-HA/PTX3 were not toxic to unstimulated RPE cells. Only HC-HA/PTX3 dose-dependently inhibited proliferation and EMT of stimulated RPE cells by down-regulating Wnt (β-catenin, LEF1) and TGF-β (Smad2/3, collagen type I, α-SMA) signaling, respectively. Additionally, HA and HC-HA/PTX3 inhibited migration but only HC-HA/PTX3 inhibited collagen gel contraction. These results suggest HC-HA/PTX3 is a non-toxic, potent inhibitor of proliferation and EMT of RPE in vitro, and HC-HA/PTX3’s ability to inhibit PVR formation warrants evaluation in an animal model.

Notch signaling modulates proliferative vitreoretinopathy via regulating retinal pigment epithelial-to-mesenchymal transition

Elevated Notch signaling has been verified in a large range of fibrotic diseases developed in the kidney, liver, and lung, inducing the development of the epithelial-mesenchymal transition (EMT). The aim of this study was to observe the involvement of Notch signaling in the EMT of retinal pigment epithelial (RPE) cells and the pathogenesis of proliferative vitreoretinopathy (PVR). In vitro cultivated human RPE cells (ARPE-19) were treated with 10 ng/mL transforming growth factor (TGF)-β1 for 24, 48, and 72 h. The expression levels of ZO-1, α-SMA, vimentin, Notch1 intracellular domain (NICD1), and Hes-1 were evaluated with quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence staining or Western blot. TGF-β1 induced EMT and the activation of Notch signaling in ARPE-19 cells. To examine the effect of Notch inhibition on TGF-β1-induced EMT and PVR formation, ARPE-19 cells were preincubated with γ-secretase inhibitor LY411575 before TGF-β1 treatment. Mouse PVR model was used for in vivo study. ARPE-19 cells were injected intravitreously with or without the LY411575 to examine the effect of Notch inhibition on PVR formation. LY411575 significantly attenuated EMT by inhibiting the Notch signaling activation in vitro. PVR was induced by intravitreal injections of ARPE-19 cells, while LY411575 inhibited mouse PVR formation in vivo. Notch signaling plays a critical role in TGF-β1-induced EMT in vitro and mice PVR model, which provides a novel insight into the pathogenesis of PVR. The specific inhibition of Notch signaling by γ-secretase inhibitor may provide a new approach for the prevention of PVR.

Chemokine CXCL-1: activity in the vitreous during proliferative vitreoretinopathy

The aim of this study was to investigate CXCL-1 chemokine levels in the vitreous during rhegmatogenous retinal detachment (RRD) with and without proliferative vitreoretinopathy (PVR) and identify possible correlations with clinical parameters (extent and duration or RRD and PVR grade). Vitreous samples from patients with primary RRD with or without PVR were collected and assayed using a double antibody enzyme-linked immunosorbent assay (ELISA). Eleven vitreous samples from organ donors were employed as a control group. CXCL-1 levels were measured in 35 vitreous samples from 35 RRD patients. Mean CXCL-1 levels (64·82 ± 6·47 pg/ml) were significantly higher (P = 0·048) compared to controls. There was a significant positive correlation between CXCL-1 levels and the extent of the detachment (r = 0·794, P = 0·006). Peak CXCL-1 levels coincided with 3+ quadrant RRD, an interim of 29-60 days' duration and PVR grade B. Increased CXCL-1 levels may be indicative of mild inflammation in the detached retina and the adjacent vitreous. The results of the present study may provide novel insight into the complex interactions taking place during the early and late stages of RRD complicated by PVR.

Traumatic retinal detachment--the difficulty and importance of correct diagnosis

Accurate characterization of a retinal detachment as traumatic is often difficult, but is important because it may instigate a careful search for occult coexistent traumatic pathology, affect the prognosis and the treatment of both eyes, influence insurance coverage benefits and medical-legal determinations, and is essential for epidemiologic studies. We review the epidemiology and pathophysiology of traumatic retinal detachment, common obstacles to correct diagnosis, diagnostic guidelines, and outline categories of traumatic causal relationships. Because there is no generally accepted definition of traumatic retinal detachment, we offer a practical one. Categorization as traumatic should be based on the particular history and physical examination rather than epidemiologic criteria.