PROGRESSION OF MYOPIC MACULOPATHY IN PATIENTS WITH MYOPIC TRACTION MACULOPATHY AFTER VITRECTOMY.

PURPOSE: To compare the progression of myopic maculopathy with or without vitrectomy in patients with myopic traction maculopathy (MTM). METHODS: Seventy-seven eyes with MTM were classified into either the observation group (n = 38) or the vitrectomy group (n = 39). Progression of myopic maculopathy was assessed with fundus photography using infrared images. Progression within stage was evaluated as an increase in the area of atrophic lesions on infrared images using ImageJ software. The rate of progression was compared using the paired t -test. RESULTS: The mean follow-up period was 60.0 ± 47.5 months. The initial mean stage of myopic maculopathy for the observation group was 1.86 ± 0.86, and it progressed to 2.00 ± 0.83 ( P = 0.023) at the last visit. For the vitrectomy group, the stage progressed from 1.82 ± 0.96 to 2.05 ± 1.09 ( P = 0.011). Four eyes (10.5%) in the observation group showed progression at 87.3 months, and seven eyes (17.9%) in the vitrectomy group showed progression at 31.3 months. CONCLUSION: Surgery in patients with MTM may accelerate the progression of myopic maculopathy. Therefore, care should be taken when considering surgery for patients with MTM.

COMPARISON OF THREE INTERNAL LIMITING MEMBRANE PEELING TECHNIQUES FOR MYOPIC TRACTION MACULOPATHY WITH HIGH RISK OF POSTOPERATIVE MACULAR HOLE DEVELOPMENT.

PURPOSE: To compare three different internal limiting membrane (ILM) peeling techniques, including standard ILM peeling, fovea-sparing ILM peeling, and inverted ILM flap (ILMF), in the treatment of myopic traction maculopathy with high risk of postoperative macular hole development. METHOD: This retrospective cohort study enrolled 101 eyes suffering from lamellar macular hole combined with myopic traction maculopathy in 98 consecutive patients who underwent vitrectomy with either standard ILM peeling, fovea-sparing ILM peeling, or ILMF from July 2017 to August 2020. All patients were followed up for at least 12 months after surgery. Best-corrected visual acuity, macular anatomical outcomes, and postoperative full-thickness macular hole (FTMH) formation were evaluated. RESULTS: No significant differences were found among the three surgical groups in baseline characteristics. 12 months after surgery, the mean best-corrected visual acuity was significantly improved ( P < 0.001) and showed no significant differences among groups ( P = 0.452). None of the eyes in the ILMF group, five eyes (15.6%) in the standard ILM peeling group, and six eyes (17.1%) in the fovea-sparing ILM peeling group developed a postoperative FTMH ( P = 0.026). Logistic regression showed that the ILM peeling technique was an independent influencing factor for FTMH formation (OR = 0.209, P = 0.014). CONCLUSION: Compared with the standard ILM peeling or fovea-sparing ILM peeling technique, the ILMF technique resulted in similar visual outcomes but a relatively low incidence of postoperative FTMH in the treatment of lamellar macular hole combined with myopic traction maculopathy. Inverted ILM flap is an effective technique for treating myopic traction maculopathy with high risk of postoperative FTMH development.

MACULAR BUCKLING COMBINED WITH VITRECTOMY AND INVERTED INTERNAL LIMITING MEMBRANE FLAP TECHNIQUE FOR MACULAR HOLES WITH MACULAR RETINOSCHISIS WITHOUT RETINAL DETACHMENT IN HIGH MYOPIA.

PURPOSE: To investigate the outcomes of macular buckling combined with vitrectomy and inverted internal limiting membrane flap technique for highly myopic full-thickness macular hole (FTMH) with macular retinoschisis. METHODS: Twenty-six eyes of 26 consecutive patients were retrospectively included. Twelve eyes underwent macular buckling alone (buckling group). Fourteen eyes underwent macular buckling and vitrectomy with an inverted internal limiting membrane flap technique (combination group). Patients were followed for at least 9 months. Rates of FTMH closure and macular retinoschisis resolution, best-corrected visual acuity gained at the final visit were evaluated. RESULTS: The mean follow-up time was 13.00 ± 3.16 months. FTMH closed in six eyes (50%) of the buckling group and 13 eyes (92.86%) of the combination group ( P = 0.026) at the final visit. The macular retinoschisis resolution rate was close between two groups (100% vs. 92.86%; P = 1.000). Both groups achieved significant improvement in best-corrected visual acuity (10.42 ± 17.25 and 16.36 ± 10.39 Early Treatment Diabetic Retinopathy Study letters; P = 0.014 and P < 0.001). The combination group achieved slightly more best-corrected visual acuity improvement, but the difference fell short of significance ( P =0.312). CONCLUSION: Combination of macular buckling and vitrectomy with the inverted internal limiting membrane flap technique could achieve a high FTMH closure rate and significant best-corrected visual acuity improvement in FTMH with macular retinoschisis.

Effect of subthreshold nanosecond laser on retinal structure and function in intermediate age-related macular degeneration.

BACKGROUND: Subthreshold nanosecond laser (SNL) treatment has been studied as a potential intervention in intermediate age-related macular degeneration (iAMD). This study investigated the effect of 100 SNL treatment spots on retinal structure and function. METHODS: A prospective single-arm interventional pilot study. SNL treatment was delivered as 100 spots around the retinal vascular arcades of the study eye (worst visual acuity) in a single session in subjects with iAMD. Multimodal retinal imaging and dark-adapted chromatic perimetry were performed at baseline and at 0.5, 3, 6 and 12 months post treatment. Post treatment changes in best corrected visual acuity (BCVA), retinal thickness, relative ellipsoid zone reflectivity (rEZR) and rod-mediated functional parameters were compared to baseline. RESULTS: Twenty-one subjects with iAMD were recruited. SNL treatment was associated with an increase in retinal thickness (p = 0.008) and decrease in rEZR (p < 0.001) at 2 weeks post laser. Recovery of retinal thickness and rEZR was observed at the 3-month post laser visit. A gradual improvement in BCVA was observed after laser treatment. The mean change in BCVA between baseline and 12-month visit was +1.9 ± 3.3 letters for the SNL treated eyes, compared to -0.4 ± 3.0 letters for the fellow eyes (p = 0.027). Rod-mediated function improved at 3 months post laser (p < 0.001) and returned to the baseline levels at 12 months post treatment. CONCLUSIONS: A single treatment with 100 SNL spots causes a short-term change in retinal structure and improvement in retinal function that are apparent at 3 months post treatment.

CLINICOPATHOLOGIC CORRELATION OF PRERETINAL TISSUES IN MYOPIC TRACTION MACULOPATHY.

PURPOSE: To evaluate histopathologic features of preretinal tissues removed from eyes with myopic traction maculopathy (MTM). METHODS: We retrospectively studied preretinal tissue specimens from eyes with MTM removed during pars plana vitrectomy. A control group of six idiopathic epiretinal membranes was studied for comparison. RESULTS: Six MTM specimens were studied histopathologically. Outer retinal schisis-like thickening was present in 100% of preoperative optical coherence tomography images; four of the six eyes had subfoveal neurosensory retinal detachment. Postoperative optical coherence tomography images demonstrated complete resolution of the schisis-like appearance in all eyes; a full-thickness macular hole occurred in two of the six eyes. Histopathologic examination disclosed fibrocellular tissue that was strongly positive for glial fibrillary acidic protein, weak to moderately positive for cytokeratin, and weakly positive for smooth muscle actin and CD68. There were no apparent histopathologic or immunohistochemical differences between preretinal tissues from eyes with MTM and idiopathic epiretinal membranes from control eyes. CONCLUSION: The outer retinal schisis-like thickening, commonly associated with subretinal fluid, that characterizes MTM is associated with preretinal tissues that are histopathologically indistinguishable from idiopathic epiretinal membranes. These findings suggest that anteroposterior traction caused by axial elongation rather than a uniquely abnormal cellular process is the etiologic mechanism of MTM.

Vitreous levels of apolipoprotein A1 and retinol binding protein 4 in human rhegmatogenous retinal detachment associated with choroidal detachment.

Purpose: This study aims to quantify the concentration of apolipoprotein A1 (APOA1) and retinol binding protein (RBP4) expressed in the vitreous humors of patients with rhegmatogenous retinal detachment associated with choroidal detachment (RRDCD), rhegmatogenous retinal detachment (RRD), and idiopathic epimacular membrane (IEM). This study also aims to investigate the potential role of APOA1 and RBP4 as biomarkers of RRDCD. Methods: Enzyme-linked immunosorbent assay (ELISA) kits were used to obtain levels of APOA1 and RBP4 from the vitreous humor samples of 76 primary patients. These patients included 23 patients with RRDCD, 28 patients with RRD, and 24 patients with IEM. All patients were undergoing planned pars plana vitrectomy. The differences between the concentrations of the molecular biomarkers among different patient groups were analyzed using the Mann-Whitney U-test for nonparametric values and independent samples t-test or one-way ANOVA analysis for parametric data. The relationship between the molecular biomarkers, grades of proliferative vitreoretinopathy (PVR), and quadrants of retinal detachment were analyzed using nonparametric Spearman's rank correlation analysis. Results: The vitreous concentrations of APOA1 and RBP4 were statistically significantly higher in the RRDCD group compared to the RRD and IEM groups. Patients with severe PVR demonstrated a higher concentration of APOA1 and RBP4 compared to those with mild PVR, but this finding was not statistically significant. There was a statistically significant positive correlation between APOA1 and RBP4 in the RRDCD and RRD groups. Nonparametric Spearman's rank correlation analysis revealed that levels of APOA1 and RBP4 increased statistically significantly with an increasing number of detached retinal quadrants in the RRDCD and RRD groups. Conclusions: The findings of this study allude to the potential of APOA1 and RBP4 as specific biomarkers of RRDCD. The findings of this study may contribute to increased understanding regarding the role of APOA1 and RBP4 in RRDCD.

Visual Evoked Potential Recovery by Subretinal Implantation of Photoelectric Dye-Coupled Thin Film Retinal Prosthesis in Monkey Eyes With Macular Degeneration.

Retinal prosthesis or artificial retina is a promising modality of treatment for outer retinal degeneration, caused by primary and secondary loss of photoreceptor cells, in hereditary retinal dystrophy and age-related macular degeneration, respectively. Okayama University-type retinal prosthesis (OUReP) is a photoelectric dye-coupled polyethylene film which generates electric potential in response to light and stimulates nearby neurons. The dye-coupled films were implanted by vitreous surgery in the subretinal space of monkey eyes with macular degeneration which had been induced by cobalt chloride injection from the scleral side. A pilot 1-month observation study involved 6 monkeys and a pivotal 6-month observation study involved 8 monkeys. Of 8 monkeys in 6-month group, 3 monkeys underwent dye-coupled film removal at 5 months and were observed further for 1 month. The amplitude of visual evoked potential which had been reduced by macular degeneration did recover at 1 month after film implantation and maintained the level at 6 months. Optical coherence tomography showed no retinal detachment, and full-field electroretinograms maintained a-wave and b-wave amplitudes, indicative of no retinal toxicity. Pathological examinations after 6-month implantation showed structural integrity of the inner retinal layer in close apposition to dye-coupled films. The implanted films which were removed by vitrectomy 5 months later showed light-evoked surface electric potentials by scanning Kelvin probe measurement. The photoelectric dye-coupled film (OUReP), which serves as a light-receiver and a displacement current generator in the subretinal space of the eye, has a potential for recovering vision in diseases with photoreceptor cell loss, such as retinitis pigmentosa and age-related macular degeneration.

VITRECTOMY FOR INTERMEDIATE AGE-RELATED MACULAR DEGENERATION ASSOCIATED WITH TANGENTIAL VITREOMACULAR TRACTION: A CLINICOPATHOLOGIC CORRELATION.

PURPOSE: To describe the morphologic characteristics of the vitreomacular interface in intermediate age-related macular degeneration associated with tangential traction due to premacular membrane formation and to correlate with optical coherence tomography (OCT) findings and clinical data. METHODS: Premacular membrane specimens were removed sequentially with the internal limiting membrane from 27 eyes of 26 patients with intermediate age-related macular degeneration during standard vitrectomy. Specimens were processed for immunocytochemical staining of epiretinal cells and extracellular matrix components. Ultrastructural analysis was performed using transmission electron microscopy. Spectral domain optical coherence tomography images and patient charts were evaluated in retrospect. RESULTS: Immunocytochemistry revealed hyalocytes and myofibroblasts as predominant cell types. Ultrastructural analysis demonstrated evidence of vitreoschisis in all eyes. Myofibroblasts with contractile properties were observed to span between folds of the internal limiting membrane and vitreous cortex collagen. Retinal pigment epithelial cells or inflammatory cells were not detected. Mean visual acuity (Snellen) showed significant improvement from 20/72 ± 20/36 to 20/41 ± 20/32 (P < 0.001) after a mean follow-up period of 19 months (median, 17 months). During this period, none of the eyes required anti-vascular endothelial growth factor therapy. CONCLUSION: Fibrocellular premacular proliferation in intermediate age-related macular degeneration predominantly consists of vitreous collagen, hyalocytes, and myofibroblasts with contractile properties. Vitreoschisis and vitreous-derived cells appear to play an important role in traction formation of this subgroup of eyes. In patients with intermediate age-related macular degeneration and contractile premacular membrane, release of traction by vitrectomy with internal limiting membrane peeling results in significantly functional and anatomical improvement.

SUBRETINAL CELL-BASED THERAPY: An Analysis of Surgical Variables to Increase Cell Survival.

PURPOSE: To develop a novel surgical approach to provide consistent delivery of cell suspension into the subretinal space without cell leakage into the vitreous. METHODS: Cell viability was assessed following mock injections to determine the optimal size cannula for delivery of the cells. A pars plana without vitrectomy approach was used to create a subretinal bleb with balanced salt solution using a 41-gauge cannula. GFP-labeled retinal pigment epithelium cells were injected through transretinal (n = 8) and transscleral (n = 16) injection approaches. Optical coherence tomography, fundus photography and autofluorescence, and histological analysis were used to evaluate surgical success. RESULTS: The 30-gauge cannula yielded the highest recovery of cells with highest viability. The transretinal approach consistently resulted in transplanted cells in the vitreous, with some cells coming to rest on the inner limiting membrane. Conversely, the transscleral approach resulted in transplantation of cells into the subretinal space in 100% of cases. Histological analysis confirmed these results. CONCLUSION: We have developed a novel surgical approach that resulted in encapsulation of transplanted cells into the subretinal space with a 100% success rate. This approach will provide a useful tool for further cell transplantation study and may provide an approach for clinical application of delivering cells to the subretinal space.

Subretinal implantation of a monolayer of human embryonic stem cell-derived retinal pigment epithelium: a feasibility and safety study in Yucatán minipigs.

PURPOSE: A subretinal implant termed CPCB-RPE1 is currently being developed to surgically replace dystrophic RPE in patients with dry age-related macular degeneration (AMD) and severe vision loss. CPCB-RPE1 is composed of a terminally differentiated, polarized human embryonic stem cell-derived RPE (hESC-RPE) monolayer pre-grown on a biocompatible, mesh-supported submicron parylene C membrane. The objective of the present delivery study was to assess the feasibility and 1-month safety of CPCB-RPE1 implantation in Yucatán minipigs, whose eyes are similar to human eyes in size and gross retinal anatomy. METHODS: This was a prospective, partially blinded, randomized study in 14 normal-sighted female Yucatán minipigs (aged 2 months, weighing 24-35 kg). Surgeons were blinded to the randomization codes and postoperative and post-mortem assessments were performed in a blinded manner. Eleven minipigs received CPCB-RPE1 while three control minipigs underwent sham surgery that generated subretinal blebs. All animals except two sham controls received combined local (Ozurdex™ dexamethasone intravitreal implant) and systemic (tacrolimus) immunosuppression or local immunosuppression alone. Correct placement of the CPCB-RPE1 implant was assessed by in vivo optical coherence tomography and post-mortem histology. hESC-RPE cells were identified using immunohistochemistry staining for TRA-1-85 (a human marker) and RPE65 (an RPE marker). As the study results of primary interest were nonnumerical no statistical analysis or tests were conducted. RESULTS: CPCB-RPE1 implants were reliably placed, without implant breakage, in the subretinal space of the minipig eye using surgical techniques similar to those that would be used in humans. Histologically, hESC-RPE cells were found to survive as an intact monolayer for 1 month based on immunohistochemistry staining for TRA-1-85 and RPE65. CONCLUSIONS: Although inconclusive regarding the necessity or benefit of systemic or local immunosuppression, our study demonstrates the feasibility and safety of CPCB-RPE1 subretinal implantation in a comparable animal model and provides an encouraging starting point for human studies.

Investigations into localized re-treatment of the retina with a 3-nanosecond laser.

BACKGROUND AND OBJECTIVES: Subvisual retinal lasers necessarily cause clinically invisible lesions, hence, they could intentionally or inadvertently be targeted at precisely the same or an overlapping location during repeat laser treatment. Herein, we investigated the structural integrity and cellular responses of localized re-treatment using a nanosecond laser (2RT) currently in trials for early age-related macular degeneration. MATERIALS AND METHODS: Rats were randomly assigned to one of five groups: sham, subvisual 2RT, subvisual 2RT re-treatment, visual effect 2RT, visual effect 2RT re-treatment. Re-treatment groups were lasered on days 0 and 21; single laser groups were only lasered on day 21. All rats were euthanized at day 28 and eyes were then dissected and processed for immunohistochemistry. For re-treatment, the laser was targeted at precisely the same locations on both delivery occasions. Analytical endpoints included monitoring of retinal vascular integrity overlying lesions, investigation into any potential choroidal neovascularization, assessment of the RPE, quantification of collateral injury to photoreceptors or other neuronal classes, and delineation of glial reactivity. RESULTS: Repeat laser administration to rats caused ostensibly identical retinal-RPE-choroid responses to those obtained in age-matched rats that received only a single application. Specifically, 7 days after treatment, RPE cells were re-populating lesion sites. No obvious consistent differences were evident between the single and repeat laser groups. Moreover, repeat laser caused no (measurable) additive injury to photoreceptors or other retinal neuronal classes from single laser treatment. In re-lasered animals, there was no increase in microglial activity overlying and adjacent to lesion sites relative to single lasered rats. Finally, there was no evidence of choroidal neovascularization after repeat laser treatment. CONCLUSIONS: The overall results provide a measure of confidence that re-treatment of patients with 2RT should not provide any additional risk of developing visual scotomas, choroidal neovascularizations, or inflammatory events. Indeed, the collated results indicate that the metabolic and structural disruption to the RPE-retina caused by short pulse duration laser treatment is resolved within a short time frame such that re-treatment elicits a phenotype indistinguishable from single treatment. Lasers Surg. Med. 48:602-615, 2016. © 2016 Wiley Periodicals, Inc.

Practical Vision: Telescope Implants Score Large.

Some assisted living or skilled nursing residents with macular degeneration may be eligible for a surgical procedure that could turn their lives around.

Evaluation of the vitreous microbial contamination rate in office-based three-port microincision vitrectomy surgery using Retrector technology.

BACKGROUND: To perform a microbiological contamination analysis of the vitreous during office-based micro-incision vitrectomy surgery (MIVS) assessing whether the bacteria detected correlated with patient's ocular conjunctival flora. METHODS: This is a prospective, interventional, nonrandomized case series of patients undergoing office-based MIVS, anti-VEGF, and dexamethasone intravitreal injections (triple therapy) for the treatment of wet age-related macular degeneration (AMD) and diabetic macular edema (DME).All patients were operated at a small procedure room in an ambulatory clinic of the Department of Ophthalmology, University of Montreal, Quebec, Canada. Conjunctival samples were done before placing the sclerotomies. The MIVS was done with a 23-gauge retractable vitrector, a 27-gauge infusion line, and a 29-gauge chandelier. Undiluted and diluted vitreous were collected for aerobic, anaerobic and fungal cultures. Outcomes measured were bacterial species identification within samples collected from the conjunctiva and the vitreous. RESULTS: Thirty-seven patients (37 eyes) were recruited and completed over 17 months of follow-up. Twenty-eight had wet AMD and nine had DME. There were 13 men and 24 women, with a mean age of 78 years. Eighteen patients (46%) had culture positive conjunctival flora. Twenty-six bacterial colonies were tabulated in total from the conjunctival swabs. All bacteria detected were gram-positive bacteria (100%), most commonly: Staphylococcus epidermitis in 11 (42%) and Corynebacterium sp. in 6 (23%). Only 1/18 patients had more than 3 species isolated, 6/18 patients had 2 species and 11/18 patients had 1 species identified on the conjunctival swab. Only 1 of the 37 undiluted midvitreous samples was culture positive, equating to a contamination rate of 2.7%. None of the diluted vitreous samples were culture positive. All cultures were negative for fungus. No serious postoperative complications occurred, including bacterial endophthalmitis, choroidal detachment, and retinal detachment. CONCLUSION: This preliminary study of office-based MIVS gives us insights on the ocular surface microbial profile and vitreous contamination rate of performing such procedures outside the OR-controlled environment. Our initial results seem to indicate that there is little risk of bacterial translocation and contamination from the conjunctiva into the vitreous. Therefore, if endophthalmitis occurs post-operatively, the source may likely arise after the procedure. Larger studies are needed to confirm our data.

[Surgery for age-related macular degeneration. Still an option in the age of pharmacotherapy?]. / Chirurgie der altersbedingten Makuladegeneration--Ist das im Zeitalter der Pharmakotherapie noch eine Option?

This review assesses the relevance of surgical approaches for age-related macular degeneration (AMD) with respect to the pathophysiology of AMD and the current pharmacological possibilities. We discuss the different surgical approaches such as subretinal membrane excision, cell transplantation (IPE and RPE) and transplantation of retina and choroid (PATCH), as well as translocation surgery. Peeling of epiretinal membranes in patients with drusen as well as vitrectomy before epiretinal brachytherapy (VIDEON system) are the final topics. While overall pharmacotherapy has displaced surgical approaches, surgery is worthy of consideration in selected cases. For these patients surgical options need to be maintained in the armamentarium of retinal surgeons.

Small-Incision new generation implantable miniature telescope surgical technique and patient outcomes.

BACKGROUND: Various ocular implants were suggested as a means of enhancing vision in patients with advanced age related macular degeneration. Recently, a new generation of implantable telescopes has been released. The purpose of this study is to report the surgical technique of implantation along with patient outcomes. METHODS: This work focuses on the surgical technique. Crucial surgical steps are carefully reported along with discussion on main drawbacks and limitations. RESULTS: This approach uses a preloaded delivery system with improved features and requires a smaller incision. First patient outcomes are also reported. CONCLUSIONS: Surgical steps to implant this preloaded intraocular telescope are easier than previous versions, however this remains a complex procedure. Initial patient functional outcomes look promising.

Pits of Fire: Post Scleral Graft Vasculitis in Patients With Optic Disc Pit Maculopathy.

Occlusive vasculitis is a rare complication following an uneventful surgery. In this article, we report two cases of optic disc pit maculopathy that underwent scleral graft and developed vasculitis following uneventful surgery. Both patients underwent autologous scleral graft for optic disc pit maculopathy through 25-gauge pars plana vitrectomy. Scleral graft was harvested from patient's same eye and plugged in the optic disc pit. After a postoperative period of approximately 3 months, both patients developed features of occlusive vasculitis with vitreous base contraction. Uveitic workup did not reveal other causes of vasculitis. Both patients were treated with topical and systemic steroids and responded well until the last follow-up. [Ophthalmic Surg Lasers Imaging Retina 2024;55:172-175.].

Early Choriocapillaris Loss in a Porcine Model of RPE Cell Debridement Precedes Pathology That Simulates Advanced Macular Degeneration.

Purpose: No large-mammal surgical models exist for geographic atrophy (GA), choroidal neovascularization (CNV), and pachychoroidal vascular remodeling. Our goal was to develop a porcine RPE debridement model of advanced macular degeneration to study photoreceptor cell loss and choroidal remodeling. Methods: Seven 2-month-old female domestic pigs were used for this study. After 25G vitrectomy, the area centralis was detached via subretinal bleb. A nitinol wire (Finesse Flex Loop) was used to debride RPE cells across a 3- to 5-mm diameter region. Fluid-air exchange was performed, and 20% SF6 gas injected. Animals underwent fundus photography, fluorescein angiography, optical coherence tomography (OCT), and OCT-angiography (OCTA) at 2 weeks, 1 month, 2 months, 3 months, and 6 months postoperatively. Retinal histology was obtained at euthanasia, 2 months (n = 3), 3 months (n = 2), or 6 months (n = 2) after surgery. Results: RPE debridement resulted in GA with rapid loss of choriocapillaris, progressive loss of photoreceptors, and pachychoroidal changes in Sattler's and Haller's layers in all seven eyes undergoing debridement within 2 months. OCT and histological findings included subretinal disciform scar with overlying outer retinal atrophy; outer retinal tubulations and subretinal hyper-reflective material. OCTA revealed type 2 CNV (n = 4) at the edges of the debridement zone by 2 months, but there was no significant exudation noted at any time point. Conclusions: Surgical debridement of the RPE results in GA, CNV, and pachychoroid and reproduced all forms of advanced macular degeneration. This surgical model may be useful in examining the role of RPE and other cell replacement in treating advanced macular disease.

Preclinical safety and stability study of a next generation telescope prosthesis for end-stage macular degeneration.

BACKGROUND: To assess the surgical procedure, safety and stability of a next generation injectable telescope prosthesis in a rabbit model. METHODS: After removal of the crystalline lenses of eight New Zealand White rabbits, the next generation device was randomly implanted in one eye, and the available telescope prosthesis (Normal device) was implanted in the fellow eye. Operative parameters (incision, capsulorrhexis size and operative time), intraoperative and postoperative complications rates, endothelial cell density changes and the distance between the corneal endothelium and the telescope (central clearance distance) were measured and compared between the groups. RESULTS: Incision size and capsulorrhexis size were smaller, and operative time was shorter in the next generation group in comparison with the Normal group. No difference was found in the intraoperative and postoperative complication rates between the groups. Endothelial cell density loss observed in the next generation group was less than the loss in the Normal group, but the difference was not significant statistically. The central clearance distance was significantly larger in the next generation group in comparison with the Normal group (P = 0.001). CONCLUSIONS: The next generation telescope was implanted through a smaller incision, with a shorter surgical time and a larger central clearance distance in the rabbit eyes, in comparison with the Normal group. The next generation device may allow reduced trauma to the corneal endothelium, better control during surgery and induce less astigmatism while preserving the optical advantages of the Food and Drug Administration-approved telescope prosthesis.