Virtual retinectomy: indocyanine green-assisted internal limiting membrane peeling as a surgical adjunct in repair of recurrent rhegmatogenous retinal detachment due to PVR

Proliferative Vitreoretinopathy: A Reappraisal

Proliferative vitreoretinopathy (PVR) remains the main cause of failure after retinal detachment (RD) surgery. Despite the development of modern technologies and sophisticated techniques for the management of RD, the growth of fibrocellular membranes within the vitreous cavity and on both sides of the retinal surface, as well as intraretinal fibrosis, can compromise surgical outcomes. Since 1983, when the term PVR was coined by the Retina Society, a lot of knowledge has been obtained about the physiopathology and risk factors of PVR, but, despite the proposal of a lot of therapeutic challenges, surgical skills seem to be the only effective way to manage PVR complications.

Effect of Macular Internal Limiting Membrane Peeling on Single Surgery Success Rates of Vitrectomy for Uncomplicated, Primary Macula-Off Retinal Detachment

Purpose: To determine the anatomic and visual outcomes of pars plana vitrectomy for uncomplicated, primary macula-off rhegmatogenous retinal detachment (RRD) with and without internal limiting membrane (ILM) peeling. Methods: This retrospective chart review comprised 129 patients with uncomplicated, primary macula-off RRD presenting between January 1, 2016, and May 31, 2021. Thirty-six patients (27.9%) had ILM peeling and 93 (72.0%) did not. The primary outcome was the rate of recurrent RRD. Secondary outcomes included preoperative and postoperative best-corrected visual acuity (BCVA), epiretinal membrane (ERM) formation, and macular thickness. Results: No significant difference was found in the risk for recurrent RRD between patients who had ILM peeling and those who did not (2.8% [1/36] and 5.4% [5/93], respectively) (P = 1.00). The final postoperative BCVA was better in eyes that did not have ILM peeling (P< .001). No ERM occurred in the group with ILM peeling, whereas ERM occurred in 27 patients (29.0%) who did not have ILM peeling. The temporal macular retina was thinner in eyes in which ILM peeling was performed. Conclusions: The risk for recurrent RRD was not statistically lower in eyes having ILM peeling of the macula in uncomplicated, primary macula-off RRD. Despite a reduction in postoperative ERM formation, eyes having macular ILM peeling had worse postoperative VA.

Intravitreal methotrexate infusion for prophylaxis of proliferative vitreoretinopathy after pars plana vitrectomy for rhegmatogenous retinal detachment

Background

Proliferative vitreoretinopathy (PVR) is the leading cause of recurrent retinal detachment after surgical repair of rhegmatogenous retinal detachment (RRD). Our study aimed to assess the efficacy and safety of intravitreal methotrexate infusion (IMI) for the prevention of PVR after pars plana vitrectomy (PPV) in eyes with RRD.

Methods

This prospective comparative interventional study was conducted from September 2020 to November 2021 at Ain Shams University Hospitals, Egypt. We recruited a consecutive, non-randomized sample of 47 eyes of 47 patients with RRD undergoing PPV. Participants were allocated to a control group or an intervention group that received IMI during surgery. Each group was subdivided into subgroups of eyes at high-risk of developing PVR and eyes with established preoperative PVR grade C. Outcome measures at the 3-month postoperative follow-up were the rate of retinal attachment, incidence of PVR, reoperation rate to flatten the retina, and changes in the retina and/or optic nerve function as assessed by full-field electroretinogram and flash visual evoked potential.

Results

Data from 47 eyes (23 and 24 eyes in the intervention and control groups, respectively) were evaluated. Subgroups IA, IB, and IIB each included 12 eyes, subgroup IIA included 11 eyes, and all subgroups had comparable sex ratios and age distributions. Postoperative PVR at 1 month and between 1 and 3 months was present in 13% and 4% of eyes in the intervention group, respectively. Reoperation to flatten the retina was required in 2 (9%) eyes in the intervention group, while 22 eyes (96%) had complete flattening of the retina at 3 months. No significant differences were found between the study groups and the corresponding subgroups regarding the outcome measures (all P > 0.05). No adverse events attributable to IMI were detected up to 3 months postoperatively.

Conclusions

Although IMI was safe for intraocular use in eyes with RRD and PVR grade C or a high risk of developing PVR, it did not affect the anatomical success rate or development of PVR up to 3 months after PPV. Further multicenter randomized clinical trials with longer follow-up periods and larger sample sizes are needed to verify these preliminary outcomes.

Translational and clinical advancements in management of proliferative vitreoretinopathy

PURPOSE OF REVIEW

Despite advancement in the surgical instrumentation and techniques, proliferative vitreoretinopathy (PVR) remains the most common cause for failure of rhegmatogenous retinal detachment (RRD) repair. This review discusses ongoing translational and clinical advancements in PVR.

RECENT FINDINGS

PVR represents an exaggerated and protracted scarring process that can occur after RRD. The primary cell types involved are retinal pigment epithelium, glial, and inflammatory cells. They interact with growth factors and cytokines derived from the breakdown of the blood-retinal barrier that trigger a cascade of cellular processes, such as epithelial-mesenchymal transition, cell migration, chemotaxis, proliferation, elaboration of basement membrane and collagen and cellular contraction, leading to overt retinal pathology. Although there are currently no medical therapies proven to be effective against PVR in humans, increased understanding of the risks factors and pathophysiology have helped guide investigations for molecular targets of PVR. The leading therapeutic candidates are drugs that mitigate growth factors, inflammation, and proliferation are the leading therapeutic candidates.

SUMMARY

Although multiple molecular targets have been investigated to prevent and treat PVR, none have yet demonstrated substantial evidence of clinical benefit in humans though some show promise. Advancements in our understanding of the pathophysiology of PVR may help develop a multipronged approach for this condition.

Extended Internal Limiting Membrane Peeling in Complex Pediatric Rhegmatogenous Retinal Detachment

PURPOSE

To assess the feasibility and investigate the anatomical and functional outcomes of extended internal limiting membrane (ILM) peeling with pars plana vitrectomy (PPV) for complex pediatric rhegmatogenous retinal detachment (RRD).

METHODS

This was a retrospective interventional case series where children (≤18 years) with RRD and severe PVR (grade C) were included. All eyes underwent PPV with ILM peeling up to 2-disk diameter beyond the vascular arcades. The main outcome measures were assessment of feasibility of ILM peeling in the pediatric RRD and evaluation of the rate of complete retinal reattachment and corrected-distance visual acuity (CDVA) at the final follow-up.

RESULTS

A total of 29 eyes (25 patients) were enrolled in this study. ILM peeling performed on these children was not more difficult than in adult eyes. After a mean follow-up of 18 months, the patients achieved final CDVA better than 20/200 in 37.9%. The initial retinal reattachment was 55.2% while the final anatomical success was 86.2%.

CONCLUSION

Vitrectomy with ILM peeling is technically feasible in pediatric RRD, limiting epiretinal proliferation and achieving favorable anatomical outcomes in cases of complex pediatric RRD. The long-term effects of ILM peeling need further investigation.

IMPACT OF INNER LIMITING MEMBRANE PEELING ON VISUAL RECOVERY AFTER VITRECTOMY FOR PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT INVOLVING THE FOVEA

PURPOSE

To assess the impact of inner limiting membrane peeling during vitrectomy for macula-involving retinal detachment on best-corrected visual acuity (VA).

METHODS

Retrospective analysis of 89 eyes with primary macula-involving retinal detachment, which was undergoing vitrectomy, endolaser, retinotomy, endodrainage, and SF6 tamponade. Membrane-blue-assisted membrane peeling had been performed in 61 of the eyes (Group 1) but not in the other 28 (Group 2), which served as controls.

RESULTS

Age, lens status, and incidence of proliferative vitreoretinopathy 26.2% versus 39.3%; P = 0.23 in the 2 groups were comparable. The preoperative visual acuity (Early Treatment Diabetic Retinopathy Study letters) was 25.7 ± 27.9 in Group 1 and 28.8 ± 29.9 in Group 2 (P = 0.47). After surgery, these rose from 62.3 ± 30.5 (Group 1) and 34.2 ± 35.8 (Group 2) after 1 week (P = 0.090), through 83.1 ± 8.0 and 57.2 ± 32.4 at 1 month (P = 0.0005), to 92.1 ± 4.5 and 74.4 ± 23.1 Early Treatment Diabetic Retinopathy Study letters after 6 months (P = 0.0005). More than 6-month incidences of proliferative vitreoretinopathy (13.1% vs. 28.6%; P = 0.13) were similar, whereas the redetachment rate (9.8% vs. 32.1%; P = 0.014), the incidence of secondary epiretinal membranes (1.6% vs. 35.7%; P = 0.0005), and the revitrectomy rate were lower in group 1 (9.8% vs. 53.6%; P = 0.0005).

CONCLUSION

Inner limiting membrane peeling during vitrectomy for macula-involving retinal detachment may substantially contribute to the visual recovery, reducing the incidence of secondary epiretinal membrane formation.

Management of recurrent rhegmatogenous retinal detachment

Rhegmatogenous retinal detachment (RRD) repair is one of the most common vitreoretinal surgeries a surgeon performs. In an ideal scenario, RRD can be repaired with a single surgical intervention; however, despite excellent skill, flawless technique, and the introduction of high-end technology, up to 10% of cases require additional interventions to ultimately repair recurrent detachments. It is thus important to study the outcomes of multiple interventions to understand whether performing repeat vitrectomy on patients with a history of failed surgeries is worthwhile. Thus, recurrent retinal detachment (re-RD) remains a significant challenge for vitreoretinal surgeons as well as the patients considering the economic and the emotional burden of undergoing multiple interventions. The advent of microincision vitrectomy system, perfluorocarbon liquids, and effective intraocular tamponades has opened new doors for managing re-RDs. In this article, we have reviewed and summarized the various causes and approaches for management for optimal anatomical and functional outcomes.

Proliferative Vitreoretinopathy: A Review

Proliferative vitreoretinopathy (PVR) is the most common cause for failure of rhegmatogenous retinal detachment repair and is characterized by the growth and contraction of cellular membranes within the vitreous cavity and on both sides of the retinal surface as well as intraretinal fibrosis. Currently, PVR is thought to be an abnormal wound healing response that is primarily driven by inflammatory, retinal, and RPE cells. At this time, surgery is the only management option for PVR as there is no proven pharmacologic agent for the treatment or prevention of PVR. Laboratory research to better understand PVR pathophysiology and clinical trials of various agents to prevent PVR formation are ongoing.

Internal Limiting Membrane Peeling in Macula-off Retinal Detachment Complicated by Grade B Proliferative Vitreoretinopathy

PURPOSE

To investigate the clinical benefit of internal limiting membrane (ILM) peeling as a surgical adjunct in the repair of primary retinal detachment (RD) complicated by grade B proliferative vitreoretinopathy (PVR).

DESIGN

Retrospective, interventional, comparative case series.

METHODS

Setting, study population, observationalprocedures and Main outcome measures.

SETTING

Institutional.

STUDY POPULATION

Seventy-five consecutive patients who underwent vitrectomy for primary macula-off RD complicated by grade B PVR.

OBSERVATIONAL PROCEDURES

Patients were divided into an ILM peeling (Group P) and a no ILM peeling group (Group NP).

MAIN OUTCOME MEASURES

Anatomic success rate, best-corrected visual acuity, and spectral-domain optical coherence tomography (SD-OCT) characteristics were collected at 1 and 6 months.

RESULTS

In all, 37 eyes with ILM peeling were included in Group P and 38 eyes without ILM peeling were included in Group NP. The anatomic success rate after single surgery was higher in Group P (89%) than in Group NP (66%, P = .03). Mean final visual acuity was 0.41 ± 0.40 logMAR in Group P vs 0.43 ± 0.22 logMAR in Group NP (P = .82). We found no epiretinal membrane (ERM) formation in Group P, whereas 5 cases of ERM (20%) were detected in Group NP (P = .012). The 2 groups did not differ in terms of cystoid macular edema occurrence, macular thickness, or photoreceptor damage.

CONCLUSIONS

ILM peeling during vitrectomy in macula-off RD complicated by grade B PVR reduces the need for a second surgery for redetachment or macular pucker.

[Surgical treatment of rhegmatogenous retinal detachments with high risk of proliferative vitreoretinopathy]

AIM

to analyze the effect of internal limiting membrane (ILM) peeling in patients undergoing 23-gauge pars plana vitrectomy for the treatment of rhegmatogenous retinal detachment (RRD) with a high risk of proliferative vitreoretinopathy (PVR).

MATERIAL AND METHODS

This was a prospective consecutive study of 231 eyes of 227 patients. All eyes underwent vitrectomy with silicone oil/gas tamponade for RRD with a high risk of PVR: in 42 eyes the ILM was peeled (group 1) and in the remaining 189 eyes - was not (group 2). The follow-up period was at least 3 months.

RESULTS

In group 1, single-surgery anatomic success was achieved in 85.4% and definitive reattachment - in 95.2% of patients. In group 2, single-surgery anatomic success was achieved in 67.2% and definitive reattachment - in 89.4% of patients. None of the patients from group 1, who had their ILM peeled, developed epiretinal membrane. Final BCVA in groups 1 and 2 was 1.2±0.5 logMAR and 1.34±0.82 logMAR respectively (p=0.297).

CONCLUSION

ILM peeling during vitrectomy in RRD patients at high risk of PVR provides high primary anatomic success rate.

Classifications for Proliferative Vitreoretinopathy (PVR): An Analysis of Their Use in Publications over the Last 15 Years

Purpose. To evaluate the current and suitable use of current proliferative vitreoretinopathy (PVR) classifications in clinical publications related to treatment. Methods. A PubMed search was undertaken using the term "proliferative vitreoretinopathy therapy". Outcome parameters were the reported PVR classification and PVR grades. The way the classifications were used in comparison to the original description was analyzed. Classification errors were also included. It was also noted whether classifications were used for comparison before and after pharmacological or surgical treatment. Results. 138 papers were included. 35 of them (25.4%) presented no classification reference or did not use any one. 103 publications (74.6%) used a standardized classification. The updated Retina Society Classification, the first Retina Society Classification, and the Silicone Study Classification were cited in 56.3%, 33.9%, and 3.8% papers, respectively. Furthermore, 3 authors (2.9%) used modified-customized classifications and 4 (3.8%) classification errors were identified. When the updated Retina Society Classification was used, only 10.4% of authors used a full C grade description. Finally, only 2 authors reported PVR grade before and after treatment. Conclusions. Our findings suggest that current classifications are of limited value in clinical practice due to the inconsistent and limited use and that it may be of benefit to produce a revised classification.

Proliferative vitreoretinopathy: A new concept of disease pathogenesis and practical consequences

During the last four decades, proliferative vitreoretinopathy (PVR) has defied the efforts of many researchers to prevent its occurrence or development. Thus, PVR is still the major complication following retinal detachment (RD) surgery and a bottle-neck for advances in cell therapy that require intraocular surgery. In this review we tried to combine basic and clinical knowledge, as an example of translational research, providing new and practical information for clinicians. PVR was defined as the proliferation of cells after RD. This idea was used for classifying PVR and also for designing experimental models used for testing many drugs, none of which were successful in humans. We summarize current information regarding the pathogenic events that follow any RD because this information may be the key for understanding and treating the earliest stages of PVR. A major focus is made on the intraretinal changes derived mainly from retinal glial cell reactivity. These responses can lead to intraretinal PVR, an entity that has not been clearly recognized. Inflammation is one of the major components of PVR, and we describe new genetic biomarkers that have the potential to predict its development. New treatment approaches are analyzed, especially those directed towards neuroprotection, which can also be useful for preventing visual loss after any RD. We also summarize the results of different surgical techniques and clinical information that is oriented toward the identification of high risk patients. Finally, we provide some recommendations for future classification of PVR and for designing comparable protocols for testing new drugs or techniques.

Expression of IGFBP-6 in a proliferative vitreoretinopathy rat model and its effects on retinal pigment epithelial cell proliferation and migration

AIM

To investigate the expression of insulin-like growth factor binding protein-6 (IGFBP-6) in a proliferative vitreoretinopathy (PVR) model and its effects on proliferation and migration in retinal pigment epithelial (RPE) cells.

METHODS

A PVR Wistar rat model was established by the intravitreal injection of RPE-J cells combined with platelet-rich plasma (PRP). The expression levels of IGFBP-6 were tested by ELISA. ARPE-19 cell proliferation was evaluated by the MTS method, and cell migration was evaluated by wound healing assays.

RESULTS

The success rate of the PVR model was 89.3% (25/28). IGFBP-6 was expressed at higher levels in the vitreous, serum and retina of rats experiencing advanced PVR (grade 3) than in the control group (vitreous: 152.80±15.08ng/mL vs 105.44±24.81ng/mL, P>0.05; serum: 93.48±9.27ng/mL vs 80.59±5.20ng/mL, P<0.05; retina: 3.02±0.38ng/mg vs 2.05±0.53ng/mg, P<0.05). In vitro, IGFBP-6 (500ng/mL) inhibited the IGF-II (50ng/mL) induced ARPE-19 cell proliferation (OD value at 24h: from 1.38±0.05 to 1.30±0.02; 48h: from 1.44±0.06 to 1.35±0.05). However, it did not affect basal or VEGF-, TGF-β- and PDGF-induced cell proliferation. IGFBP-6 (500ng/mL) reduced the IGF-II (50ng/mL)-induced would healing rate [24h: from (43.91±3.85)% to (29.76±2.49)%; 48 h: from (66.09±1.67)% to (59.88±3.43)%].

CONCLUSION

Concentrations of IGFBP-6 increased in the vitreous, serum, and retinas only in advanced PVR in vivo. IGFBP-6 also inhibited IGF-II-induced cell proliferation in a not dose or time dependent manner and migration. IGFBP-6 participates in the development of PVR and might play a protective role in PVR.