PREVALENCE OF VITREOUS CORTEX REMNANTS IN EYES WITH PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT UNDERGOING VITRECTOMY

Proliferative vitreoretinopathy: a revised concept of retinal injury and response

Previous concepts for the pathogenesis of proliferative vitreoretinopathy (PVR) have focused on the central role of retinal pigment epithelium cells only, potentially contributing to the lack of clinical advances. More recent studies have demonstrated the essential role of retinal glial cells in the PVR healing response but failed to identify a consistent triggering mechanism.We propose a revised concept for the pathogenesis of PVR based on retinal injury and response. A posterior vitreous detachment (PVD) is invariably present in patients with rhegmatogenous retinal detachment and PVR. There is evidence to suggest that the shearing forces of acute PVD can cause mechanical injury to the inner retina and trigger a subsequent intraretinal glial healing response. That response is characterised by subclinical glial cell activation and proliferation that may then be amplified into full-blown PVR by coexisting pathology such as retinal breaks and detachment.Whether a PVD causes interface pathology depends on the plane of separation of the posterior vitreous and areas of increased vitreoretinal adhesions. If the vitreous separates in a plane or location that damages the inner retina then glial cell activation and proliferation are likely to develop. The severity of the subclinical inner retinal damage may then represent one of the missing links in our understanding of the pathogenesis of PVR and would explain many of the findings we encounter in clinical practice. Controlling the process of acute PVD and subsequent intraretinal response may be essential in the prevention and management of PVR.

Selective internal limiting membrane peeling for prevention of secondary epiretinal membrane after vitrectomy for rhegmatogenous retinal detachment

PURPOSE

We introduce selective internal limiting membrane (ILM) peeling, a guideline procedure to determine whether to remove the ILM during vitrectomy for rhegmatogenous retinal detachment (RRD).

STUDY DESIGN

Retrospective case series METHODS: Patients who underwent pars plana vitrectomy for RRD and were followed up for 12 months or longer were included. When vitreous cortex remnants (VCRs) were detected with triamcinolone acetonide, the ILM was removed; otherwise, the ILM was preserved ("selective ILM peeling"). The factors associated with the presence of VCRs and incidence of secondary epiretinal membrane (ERM) were analyzed.

RESULTS

VCRs were detected in 87 of 133 eyes (65.4%) in which the ILM was removed. Younger age, better preoperative visual acuity, and vitreous hemorrhage were negatively correlated with the presence of VCRs. No ERM occurred in the eyes after ILM peeling. Among the eyes with ILM preservation, subclinical ERM was noticed in 4 eyes (8.7%), and 1 eye (2.1%) required additional surgery owing to ERM. ERM occurred more commonly in eyes with the ILM preserved (P = .004). However, no differences in the rate of additional surgeries were found between the 2 groups.

CONCLUSION

Selective ILM peeling offers an alternative option to reduce the burden of ILM peeling or additional surgery.

Prevalence of vitreoschisis-induced vitreous cortex remnants over the peripheral retinal surface in eyes undergoing vitrectomy for primary rhegmatogenous retinal detachment

PURPOSE

Unremoved vitreoschisis-induced vitreous cortex remnants over the peripheral retinal surface posterior to the vitreous base (pVCR) may increase the risk of surgical failure after primary rhegmatogenous retinal detachment (RRD) repair. The purpose of this study was to validate our previous findings on pVCR prevalence during vitrectomy for RRD and to examine their association with proliferative vitreoretinopathy (PVR) and surgical failure.

METHODS

Prospective observational multisurgeon study of 100 eyes of 100 consecutive patients who underwent vitrectomy for RRD by one of four vitreoretinal surgeons. Collected data included detected pVCR and known PVR risk factors. Pooled analysis with our previous retrospective study (251 eyes of 251 patients) was also performed.

RESULTS

Initial PVR (≥C) was present and removed in 6/100 (6%) patients, pVCR were detected in 36/100 (36%) patients, pVCR were removed in 30/36 (83%) patients with pVCR, and 4/36 (11%) patients with pVCR were high myopes (≤-6D). Six per cent (6/100) developed a retinal redetachment, of which 3/6 (50%) had initial PVR (≥C). Surgical failure rates in eyes with and without pVCR were 17% (6/36) and 0% (0/64), respectively. In eyes with pVCR and surgical failure, pVCR were not or not completely removed during the first surgery. Overall analysis showed that pVCR were statistically significantly associated with PVR.

CONCLUSIONS

This study confirms our previous findings: a pVCR prevalence of around 35% and an association between pVCR, PVR formation and surgical failure in patients undergoing vitrectomy for RRD. More research is needed to determine which patients would benefit most from pVCR removal.

Vitreous Cortex Remnants Removal With Beveled Vitrectomy Probe During Vitrectomy For Primary Rhegmatogenous Retinal Detachment

PURPOSE

To introduce a new surgical technique with a beveled vitrectomy probe for the removal of peripheral vitreous cortex remnants (VCR) in primary rhegmatogenous retinal detachment (RRD).

METHODS

This study was a retrospective case series. From September 2019 to June 2022, 54 patients with complete or partial posterior vitreous detachment who underwent vitrectomy for primary RRD by a single surgeon were enrolled.

RESULTS

After staining the vitreous with triamcinolone acetonide, the presence of VCR was assessed in detail. If VCR were present, the macular VCR were removed using surgical forceps, and then, a free flap of peripheral VCR was used as a handle for removing peripheral VCR using the beveled vitrectomy probe. Of the total patients, the presence of VCR was confirmed in 16 patients (29.6%). There were no intraoperative or postoperative complications, except for retinal redetachment caused by proliferative vitreoretinopathy, that occurred in only one eye (1.9%).

CONCLUSION

Using a beveled vitrectomy probe was a practical solution for removing VCR during RRD vitrectomy because additional instruments were not needed and risk of iatrogenic retinal damage was low.

Biomarkers of Vitreous Cortex Remnants in Eyes With Primary Rhegmatogenous Retinal Detachment

Purpose

The purpose of this study was to identify pre-operative biomarkers of vitreous cortex remnants (VCRs) in eyes with rhegmatogenous retinal detachment (RRD).

Methods

Prospective case series of 103 eyes treated with pars plana vitrectomy (PPV) to repair RRD. Pre-operatively, optical coherence tomography (OCT) and B-scan ultrasonography (US) were used to study the vitreo-retinal interface and vitreous cortex status. If detected during PPV, VCRs were removed. Images acquired pre-operatively were compared with intra-operative findings and with postoperative OCT images taken at 1, 3, and 6 months of follow-up. Multivariate regression analyses were performed to determine associations between VCRs and pre-operative variables.

Results

The presence of VCRs at the macula (mVCRs) and at the periphery (pVCRs), was ascertained intra-operatively in 57.3% and 53.4% of the eyes, respectively. Pre-operatively, a preretinal hyper-reflective layer (PHL) and a saw-toothed aspect of the retinal surface (SRS) were identified with OCT in 73.8% and 66% of the eyes, respectively. US sections showed a vitreous cortex running close and parallel to the detached retina upon static and kinetic examination (the "lining sign") in 52.4% of the cases. Multivariate regression analyses showed an association between PHL and SRS and intra-operative evidence of mVCRs (P = 0.003 and < 0.0001, respectively) and between SRS and "lining sign" and pVCRs (P = 0.0006 and 0.04, respectively).

Conclusions

PHL and SRS on OCT and the "lining sign" on US appear to be useful pre-operative biomarkers of the intra-operative presence of VCRs.

Translational Relevance

Preoperative identification of VCRs biomarkers may help to plan the operating strategy in eyes with RRD.

Is There a Link Between Vitreous Cortex Remnants and Anatomic Outcome of Vitrectomy for Primary Rhegmatogenous Retinal Detachment?

Purpose

To study the anatomic outcome of leaving vitreous cortex remnants (VCR) during pars plana vitrectomy (PPV) for primary rhegmatogenous retinal detachment (RRD).

Methods

The study comprised patients with RRD who had PPV by a single surgeon between January 2019 and December 2020 and followed for 6 months. After intravitreal injection of triamcinolone acetonide, the topographic pattern of VCR at the periphery (p) and macula (m) was divided into 2 types by extent: complete or 4 quadrants (pVCR4Q), and between 2 and 4 quadrants ≥2 quadrants (pVCR>2Q), or by location >1 inferior retinal quadrant (pVCR>1InfQ), and at the macula (mVCR). Anatomical failure or retinal re-detachment within 6 months after surgery was the primary outcome measures. The occurrence of grade C proliferative vitreoretinopathy (PVR) and epiretinal membrane (ERM) were used as secondary outcome indicators.

Results

A 6-month prospective follow-up was performed on 103 patients. pVCR4Q was detected in 31 eyes, pVCR>2Q in 40 eyes, pVCR>1InfQ in 40 eyes and mVCR in 54 eyes. Recurrent RRD developed in 9 (8.7%) eyes, PVR grade C in 6 (5.8%) eyes and ERM in 11 (10.7%) eyes. According to multivariate regression analysis, the existence of any type of VCR did not correlate with anatomical failure, PVR or ERM.

Conclusion

The initial success rate of PPV and the growth of PVR or ERM do not appear to be impacted by keeping VCR.

The cause of redetachment after vitrectomy with air tamponade for a cohort of 1715 patients with retinal detachment: an analysis of retinal breaks reopening

BACKGROUND

To investigate the prevalence and predictors of retinal breaks reopening after vitrectomy with air tamponade in rhegmatogenous retinal detachment (RRD).

METHODS

A retrospective cohort study was conducted in Shanghai General Hospital. Chart review was performed among 1715 patients with primary RRD who received pars plana vitrectomy (PPV) with air tamponade as initial management. Patients were followed up for recurrence. The clinical features of the eyes with retinal breaks reopening were recorded. Logistic regression was constructed to investigate the predictors for breaks reopening.

RESULTS

A total of 137 (7.99%) patients had recurrent retinal detachment after PPV with air tamponade. The causes of surgery failure included new or missed retinal breaks (48.9%), reopening of original tears (43.8%) and proliferative vitreoretinopathy (7.3%). The median time to recurrence for the patients with breaks reopening was 18.0 days. Multivariate logistic regression indicated that the presence of retinal break(s) ≥ 1.5 disc diameters (DD) (odds ratio [OR]: 2.68, 95% confidence interval [CI]: 11.04-6.92, P = 0.041), and shorter period for restricted activities (OR: 0.94, 95% CI: 0.89-0.99, P = 0.020) were the independent predictors for breaks reopening.

CONCLUSIONS

Breaks reopening is an important cause for retinal redetachment after PPV with air tamponade in primary RRD. The first 2-4 weeks after surgery is the "risk period" for breaks reopening. Special attention should be paid for patients with retinal break(s) ≥ 1.5 DD. A prolonged period for restricted activities is recommended.

Utility of Removal of Vitreous Cortex Remnants during Vitrectomy for Primary Rhegmatogenous Retinal Detachment Repair

PURPOSE

To investigate the prevalence of vitreous cortex remnants (VCR) in primary rhegmatogenous retinal detachment (RRD) and the utility of VCR removal using diamond-dusted membrane scrapers (DDMS) during pars plana vitrectomy (PPV).

METHODS

One hundred and eighty-seven eyes (187 consecutive patients) were retrospectively studied. We evaluated the prevalence of VCR on the retinal surface extending from the macula to outside the vascular arcade in eyes that underwent PPV for primary RRD by a single surgeon between July 2014 and February 2021. The VCR outside the vascular arcade was completely removed using a DDMS. Preoperative factors and surgical outcomes were compared between eyes with VCR removed intraoperatively to those without VCR.

RESULTS

VCR was present and removed (group A) in 86 (46%) eyes and absent (group B) in 101 (54%) eyes. Patients with VCR were significantly older than those without (P = 0.006). The preoperative BCVA (logMAR) tended to be worse in group A (1.23 ± 0.92 [Snellen equivalent, 20/340]) than in group B (1.03 ± 0.89 [20/214]), however, the difference was not statistically significant (P = 0.095). There were no between-group differences in postoperative BCVA (group A; 0.44 ± 0.54 [20/55]; group B; 0.42 ± 0.50 [20/53]; P = 0.38). Single surgery anatomic success (group A; 90%, group B; 91%, P = 0.573) and the incidence of postoperative PVR (group A; 9%, group B; 6%, P = 0.554) were comparable between the groups.

CONCLUSIONS

Nearly half of the patients had VCR, which was more likely to occur in older patients. VCR removal resulted in favorable functional and anatomic outcomes similar to those in eyes without any VCR in patients with RRD.

Novel insights into the pathophysiology of proliferative vitreoretinopathy: The role of vitreoschisis-induced vitreous cortex remnants

PURPOSE

We previously hypothesized a causal relationship between vitreoschisis-induced vitreous cortex remnants (VCR) and the development of proliferative vitreoretinopathy (PVR). This study aims to substantiate this association through histopathological analysis of surgical specimens in support of strategies to improve therapeutic outcomes.

METHODS

A descriptive, prospective, non-consecutive case series. Histopathological and immunohistochemical analyses were performed on membranes removed from the peripheral retinal surface during initial vitrectomy for primary rhegmatogenous retinal detachment (RRD) (n = 11) or recurrent retinal detachment (n = 12). The clinical aspect of the membranes ranged from loose-meshed membranes visualized with triamcinolone to more fibrotic membranes stained with trypan blue.

RESULTS

Consistent with the clinical presentation, histopathological analysis revealed membranes with different area characteristics. Paucicellular lamellar collagen-rich areas, suggestive of VCR, appeared to transition to areas of increased cellularity and eventually more fibrotic areas of low cellularity. Five different area characteristics could be identified that seemed to correspond to five histopathological stages in PVR formation, with lamellar VCR collagen acting as an essential precondition: 1. Lamellar collagen, low cellularity (hyalocytes). 2. Lamellar collagen, increased cellularity (hyalocytes, glial cells). 3. Lamellar collagen, high cellularity (macrophages, glial cells, RPE-cells). 4. Early fibrosis, decreased cellularity (myofibroblasts). 5. Fibrosis, low cellularity (myofibroblasts).

CONCLUSION

These findings confirm the role of VCR in preretinal PVR formation posterior to the vitreous base. We propose that the presence of VCR over the retinal surface should be qualified as a risk factor for PVR formation. Detection and adequate removal of VCR may improve the success rate of vitreoretinal surgeries.