Combined pars plana vitrectomy-scleral buckle versus pars plana vitrectomy for proliferative vitreoretinopathy

Retinotomies and retinectomies: A review of indications, techniques, results, and complications

Retinotomy refers to "cutting" or "incising" the retina, whereas retinectomy denotes "excising" the retina. Retinotomies and retinectomies aid in tackling traction and retinal shortening that persist following membrane dissection and scleral buckling. We performed a literature search using Google Scholar and PubMed, followed by a review of the references procured. All relevant literature was studied in detail and summarized. We discuss the indications of retinotomies and retinectomies for relaxing retinal stiffness, accessing the subretinal space for choroidal neovascular membrane, hemorrhage and abscess clearance, drainage retinotomies to allow retinal flattening, radial retinotomies to release circumferential traction, harvesting free retinal grafts, and prophylactic chorioretinectomies in trauma.

Outcomes in primary uncomplicated rhegmatogenous retinal detachment repair using pars plana vitrectomy with or without scleral buckle

PURPOSE

To compare outcomes following primary uncomplicated rhegmatogenous retinal detachment (RRD) repair using pars plana vitrectomy (PPV) or PPV with scleral buckle (PPV-SB).

METHODS

This is a retrospective cohort study with propensity score analysis in a single tertiary care center between 2014 and 2018 comparing patients with primary uncomplicated RRD repaired using PPV only or PPV-SB (full cohort: n=1516, propensity-matched cohort: n=908). The primary outcome was single surgery anatomic success (SSAS), while secondary outcomes were 3-month and final pinhole visual acuity (PHVA) in logarithm of the minimum angle of resolution (logMAR) and final retina status.

RESULTS

In the full cohort, SSAS was achieved in 745 (91%) of PPV patients vs. 623 (89%) of PPV-SB patients (p=0.13). This was 390 (92%) vs. 314 (88%) in phakic patients (p=0.06) compared to 353 (91%) vs. 301 (90%) in pseudophakic patients (p=0.79), respectively. After matching, SSAS was achieved in 424 (93%) of PPV patients vs. 412 (91%) of PPV-SB patients (p=0.14). Median PHVA after PPV was better at 3 months (PPV: 20/40 vs. PPV-SB: 20/50; both cohorts: p<0.001) and final follow-up (PPV: 20/29 vs. PPV-SB: 20/38; full cohort: p<0.001 and PPV: 20/29 vs. PPV-SB: 20/36; matched cohort: p<0.001).

CONCLUSION

Addition of SB does not significantly change the rate of SSAS compared to PPV only in primary uncomplicated RRD. It is also associated with worse PHVA at follow-up.

Scleral Buckle versus Pars Plana Vitrectomy in the Management of Primary Chronic Rhegmatogenous Retinal Detachment: A Comparison of Anatomical and Visual Outcomes

PURPOSE:

The purpose of this study is to compare the anatomical and visual outcomes of scleral buckle (SB) surgery with the pars plana vitrectomy (PPV) in the management of chronic rhegmatogenous retinal detachment.

METHODS:

This cohort study included patients who underwent surgical repair SB group and PPV group for chronic retinal detachment during 2014–2018 at the King Khalid Eye Specialist Hospital, Riyadh. The anatomical and functional success rate at 12 months after surgery was compared in two groups. Cox regression and linear regression analysis were performed to identify the predictor of anatomical and functional outcomes, respectively. Need for second surgery was also evaluated.

RESULTS:

Our cohort had 68 eyes in SB and 64 eyes in PPV group. Eyes that underwent PPV were more likely to develop retinal detachment over 12 months than those that underwent SB surgery (adjusted heart rates 2.11, 95% confidence interval [CI], 0.95–4.64 P = 0.065). A multivariable linear regression analysis did not reveal a significant association between the surgery type and change in visual acuity (beta coefficient, 0.002; 95% CI,−0.184, 0.189 for specific bread volume; P = 0.979). A higher percentage of eyes in the PPV group compared with those in the SB surgery group required secondary surgery (39.1% vs. 22.1%; P = 0.034).

CONCLUSION:

Scleral buckling surgery showed a better single surgery anatomic success rate as compared to PPV in the management of chronic primary rhegmatogenous retinal detachment. The functional outcome of the two procedures was comparable.

Pars Plana Vitrectomy With or Without Circumferential Scleral Buckling for Primary Repair of Retinal Detachments Secondary to Retinal Dialysis

PURPOSE

The aim of this study was to evaluate the anatomical and functional outcomes after pars plana vitrectomy with or without circumferential scleral buckling, in patients with retinal detachment secondary to retinal dialysis.

DESIGN

Case series.

METHODS

A retrospective consecutive case series involving 30 eyes of 30 patients with retinal detachments secondary to retinal dialysis was completed. All 30 patients underwent primary pars plana vitrectomy, with the addition of a circumferential scleral buckle in 24 patients. The main outcome measure was the primary reattachment rate at 6 months after a single surgery.

RESULTS

Primary anatomical success was achieved in 90% of patients. The final anatomical success rate was 93%, with 4 of 30 eyes still having silicone oil in situ. The main indication for vitrectomy surgery was an inadequate fundal view for scleral buckle surgery alone. The macula was detached in 50% of patients and proliferative vitreoretinopathy grade C was found in 23% of cases. The mean preoperative visual acuity was 20/814 (range 20/20-light perception) and the mean postoperative visual acuity was 20/258 (range 20/20-hand movements).

CONCLUSIONS

Good final anatomical success rates can be achieved with pars plans vitrectomy, plus or minus circumferential buckling, in patients with retinal detachments secondary to retinal dialysis.

Two-staged surgery as an alternative to buckle-vitrectomy for rhegmatogenous retinal detachment complicated by choroidal detachment

AIM

To evaluate the outcome and safety profile of short-term perfluorocarbon liquids (PFCL) tamponade in comparison with buckle-vitrectomy in case of rhegmatogenous retinal detachment (RRD) associated with choroidal detachment (CD).

METHODS

Records of patients who underwent surgery for RRD/CD from January 2016 to July 2019 were reviewed retrospectively. The patients were allocated into two groups-group 1 patients underwent buckle-vitrectomy, while those in group 2 underwent a two-staged vitrectomy with short-term (5 days) PFCL tamponade.

RESULTS

The study included 33 eyes (33 patients) with mean age of 50.3 ± 17.2 years. Group 1 included 15 patients, while group 2 included 18. The pre-operative characteristics were similar in both the groups. The mean pre-operative intraocular pressure in group 1 and 2 was 9.1 ± 4.0 and 8.6 ± 5.2 mmHg, respectively (p = 0.755). Retinal re-attachment after single surgery was achieved in 10 (66.7%) and 14 eyes (77.8%), respectively. All the eyes achieved retinal re-attachment after repeat surgery in both the groups (1.40 vs 1.39 surgeries, p = 0.963). Post-surgery visual improvement was seen in 13 (86.7%) and 17 eyes (94.4%), respectively (p = 0.579). Final visual acuity of ≥ 6/60 was obtained in 7 (46.7%) and 9 eyes (50.0%), respectively (p > 0.999). None of the patients needed retinectomy during repeat surgery. None of the patients experienced exaggerated inflammation or intractable raised IOP spike which could not be controlled with medications.

CONCLUSION

Surgical outcomes were similar in both the groups. No clinically apparent toxicity was seen with post-operative short-term PFCL tamponade. Two-staged surgery is a good alternative to buckle-vitrectomy for eyes with RRD associated with CD.

Vitreous concentrations of vascular endothelial growth factor as a potential biomarker for postoperative complications following pars plana vitrectomy

INTRODUCTION

The aim of the study was to investigate the effects of vascular endothelial growth factor (VEGF) concentration in vitreous on postoperative complications after pars plana vitrectomy (PPV).

MATERIAL AND METHODS

Ninety subjects were surgically treated with PPV and followed up for 12 months at the Clinical Centre University Sarajevo, Clinic for Eye Disease. Exclusion criteria were presence of other eye diseases, systemic acute/chronic inflammatory conditions, or malignant neoplasms; previously performed PPV surgery; previously received intravitreal or systemic anti-VEGF therapy. A vitreous sample was obtained while performing the PPV procedure, using the Quantikine ELISA test to determine VEGF level, as a risk factor. Outcome measures were intraoperative and postoperative complications reported using categorical data: blunt and sharp dissection of membranes, intraoperative hemorrhage stopped by increasing infusion pressure, pressing with blunt instrument, or using diathermy. The following postoperative complications were assessed on the first day and at the 12-month follow-up visit: vitreous hemorrhage, fibrovascular proliferation (FVP), rubeosis iridis, and neovascular glaucoma (NVG).

RESULTS

Levels of vitreous VEGF at the time of PPV were significantly higher in eyes with: vitreous hemorrhage on the first day after PPV (p = 0.003); FVP on the first day and 12 months after PPV (p = 0.002 and p < 0.001, respectively); iris rubeosis on the first day and 12 months after PPV surgery (p < 0.001, and p = 0.001, respectively); NVG on the first day and 12 months after PPV surgery (p = 0.043 and p = 0.011, respectively), compared to the eyes without complications.

CONCLUSIONS

Preoperative levels of VEGF in vitreous can be a useful biomarker and predictor of the postoperative outcome in terms of intraoperative and postoperative complications.

5-Fluorouracyl added infusion fluid in patients with recurrent rhegmatogeneous retinal detachment

Purpose

To compare the efficacy of 5-fluorouracil (5-FU) added the infusion fluid with a control group in the event of grade C PVR in recurrent retinal detachment (RD).

Methods

The records of the patients with recurrent retinal detachment with grade C PVR who underwent vitrectomy for retinal detachment surgery between April 2003 and October 2004 were reviewed retrospectively for this comparative study. The recurrent retinal detachment patients with grade C PVR who underwent vitrectomy and had a minimum post-operative follow-up period of 12 months were included. The patients were divided into two groups as study and control groups. 5-FU (200 microgram/ml) and low-molecular-weight-heparin (LMWH) (5 IU/ml) was added into the infusion solution of the study group. Primary outcome measure of this study was the single operation anatomical success at month 12.

Results

A total of 43 eyes of 43 patients were included. The control group was consisted of 26 eyes (60.5%) and the 5-FU group was consisted of 17 eyes (39.5%). At month 12, single operation anatomical success was obtained in 14 of the 26 patients (53.8%) in the control group and in 16 of the 17 patients (94.1%) in the 5-FU group (p = 0.005).

Conclusion

Favorable outcomes were obtained in the patients with recurrent RD and grade C PVR in whom 5-FU and LMWH added infusion fluid which was used during vitrectomy.

Knockdown of Fibromodulin Inhibits Proliferation and Migration of RPE Cell via the VEGFR2-AKT Pathway

Purpose

Recent research has provided novel insight into the function of fibromodulin (FMOD) in wound healing and angiogenesis. The role of FMOD in initiation of proliferative vitreoretinopathy (PVR) has not been studied. This study investigated the effect of FMOD on human retinal pigment epithelial (RPE) cell, which plays an essential role in the progression of PVR, and the possible mechanisms.

Methods

Small interfering (si) RNA-based gene transfer technology was used to decrease FMOD expression and to study its effects on RPEs in vitro. Cell Counting Kit-8 assays, transwells, and flow cytometry analysis were used to measure cell proliferation, migration, cell cycle, and apoptosis. Western blot was used to measure expression of vascular endothelial growth factor (VEGF), VEGF receptor 2 (VEGFR2), extracellular signal-related kinase 1/2 (ERK1/2), and phosphoinositide 3 kinase (PI3K/AKT).

Results

After transfection of RPEs with a FMOD-specific siRNA, cell proliferation and migration were inhibited to the percentage of 65% ± 5% and 39% ± 10%, respectively, compared to the control group. Depletion of FMOD induced cell cycle arrest and apoptosis in RPE cells. Downregulation of VEGF, VEGFR2, and phosphorylated AKT (p-AKT) were detected in transfected RPEs.

Conclusion

Depletion of FMOD selectively downregulated the expression of VEGF and VEGFR2 and inhibited the signaling pathway of AKT phosphorylation, which consequently inhibited the proliferation and migration of RPE Cell.

LYTAK1 attenuates proliferation of retinal pigment epithelial cells through TGF-β-mediated epithelial-mesenchymal transition via the ERK/AKT signaling pathway

Retinal pigment epithelial (RPE) cells have crucial roles in the initiation and development of human ophthalmic diseases. Our previous study suggested that transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1) is a potential target in the progression and pathogenesis of human proliferative vitreoretinopathy disease. The present study further analyzed the role of TAK1 inhibitor, LYTAK1, in human RPE cells and explored the potential molecular mechanism of LYTAK1-mediated proliferation of human RPE cells. Proliferation of human RPE cells was investigated following treatment with LYTAK1 and knockdown of TGF-β. TGF-β-mediated epithelial-mesenchymal transition (EMT) through regulation of the extracellular signal-regulated kinase (ERK)/protein kinase B (AKT) signaling pathway was also explored to analyze the LYTAK1-mediated mechanism of proliferation in human RPE cells. The present results demonstrated that LYTAK1 administration suppressed TAK1 gene and protein expression in human RPE cells. LYTAK1 administration also inhibited proliferation and migration of human RPE cells in vitro. Outcomes indicated that LYTAK1 treatment downregulated expression levels of TGF-β1 and EMT markers, including cadherin, fibronectin and α-smooth muscle actin in human RPE cells. Notably, results demonstrated that the ERK/AKT signal pathway was blocked by LYTAK1 in human RPE cells. Knockdown of TGF-β markedly inhibited phosphorylation and activity of TAK1 and suppressed the LYTAK1-mediated ERK/AKT signaling pathway in RPE cells, which further canceled inhibition of RPE cell proliferation by LYTAK1. In conclusion, these findings indicated that LYTAK1 may inhibit RPE cell proliferation through the TGF-β-mediated EMT/ERK/AKT signaling pathway, suggesting that TAK1 may be a potential target for the treatment of RPE diseases.

Minireview: Fibronectin in retinal disease

Retinal fibrosis, characterized by dysregulation of extracellular matrix (ECM) protein deposition by retinal endothelial cells, pigment epithelial cells, and other resident cell-types, is a unifying feature of several common retinal diseases. Fibronectin is an early constituent of newly deposited ECM and serves as a template for assembly of other ECM proteins, including collagens. Under physiologic conditions, fibronectin is found in all layers of Bruch's membrane. Proliferative vitreoretinopathy (PVR), a complication of retinal surgery, is characterized by ECM accumulation. Among the earliest histologic manifestations of diabetic retinopathy (DR) is capillary basement membrane thickening, which occurs due to perturbations in ECM homeostasis. Neovascularization, the hallmark of late stage DR as well as exudative age-related macular degeneration (AMD), involves ECM assembly as a scaffold for the aberrant new vessel architecture. Rodent models of retinal injury demonstrate a key role for fibronectin in complications characteristic of PVR, including retinal detachment. In mouse models of DR, reducing fibronectin gene expression has been shown to arrest the accumulation of ECM in the capillary basement membrane. Alterations in matrix metalloproteinase activity thought to be important in the pathogenesis of AMD impact the turnover of fibronectin matrix as well as collagens. Growth factors involved in PVR, AMD, and DR, such as PDGF and TGFβ, are known to stimulate fibronectin matrix assembly. A deeper understanding of how pathologic ECM deposition contributes to disease progression may help to identify novel targets for therapeutic intervention.