To assess the safety of injecting human embryonic stem cell retinal pigment epithelial cell dose to treat Stargardt disease.
In this prospective, Phase I clinical trial, human embryonic stem cell ...retinal pigment epithelial cells in suspension were injected into the subretinal space in eyes with the worse best-corrected visual acuity (BCVA). After vitrectomy/posterior hyaloid removal, a partial retinal detachment was created and the human embryonic stem cell retinal pigment epithelial cells were administered. Phacoemulsification with intraocular lens implantation was performed in eyes with lens opacity. All procedures were optical coherence tomography-guided. The 12-month follow-up included retinal imaging, optical coherence tomography, visual field/electrophysiologic testing, and systemic evaluation. The main outcome was the absence of ocular/systemic inflammation or rejection, tumor formation, or toxicity during follow-up.
The mean baseline BCVAs in the phacoemulsification and no phacoemulsification groups were similar (1.950 ± 0.446 and 1.575 ± 0.303, respectively). One year postoperatively, treated eyes showed a nonsignificant increase in BCVA. No adverse effects occurred during follow-up. Intraoperative optical coherence tomography was important for guiding all procedures.
This surgical procedure was feasible and safe without cellular migration, rejection, inflammation, or development of ocular or systemic tumors during follow-up.
The neovascular form of age-related macular degeneration (AMD), called wet-AMD or choroidal neovascularisation, begins with damage to the outer retinal cells and retinal pigment epithelium (RPE), ...which elicits a cascade of inflammatory and angiogenic responses leading to neovascularisation under the macula. Studies showed that oxidative damage, chronic inflammation of the RPE and complement misregulation work at different steps of this disease. After established neovascularisation, several pro- and antiangiogenic agents start to play an important role. Vascular endothelial growth factors (VEGFs) are the most specific and potent regulators of angiogenesis, which are inhibited by intravitreal injections of ranibizumab, bevacizumab, VEGF Trap, pegaptanib sodium and other agents under investigation. Pigment epithelium-derived factor, on the other hand, shows neuroprotective and antiangiogenic activities. Hepatocyte growth factor (HGF) has a mitogenic effect on a wide range of epithelial and endothelial cells, and it is inhibited by an anti-HGF monoclonal antibody. Platelet-derived growth factor is a potent chemoattractant and mitogen for both fibroblasts and retinal RPE cells, which has been inhibited experimentally by VEGF Trap and human anti-platelet-derived growth factor-D monoclonal antibody. Fibroblast growth factor-2 has pleiotropic effects in different cell and organ systems, and it is blocked by anti-FGF antibodies, with a greater benefit regarding antiangiogenesis when combined treatment with anti-VEGF is performed. Tumour necrosis factor alpha is expressed in the retina and the choroid, and its blockade in choroidal neovascularisation includes the use of monoclonals such as infliximab. This paper reviews the most important cytokines involved in the pathogenesis of wet-AMD, with emphasis on potential combined therapies for disease control.
To study the efficacy and safety of treatments with ranibizumab and bevacizumab for exudative age-related macular degeneration.
A parallel randomized clinical trial was conducted to compare the ...efficacy and safety of three regimens (bevacizumab every month, bevacizumab every 2 weeks, and ranibizumab every month), followed by as-needed retreatments, for 1 year, in previously untreated individuals with age-related macular degeneration. The primary outcome was change in visual acuity and in central macular thickness after 1 year of follow-up. Subjects were assigned randomly to one of the three groups in a 1:1:1 ratio, and investigators and examiners were blinded to the randomization results.
We included 15 patients in each group. After 1 year of follow-up, we found statistically significant improvements in visual acuity and central macular thickness reduction in all groups. However, we found no statistically significant differences between the three groups.
The bi-weekly follow-up was effective and we found no significant differences in efficacy or safety between the treatments with ranibizumab and bevacizumab.
To determine the effects of lens status on the success rate of primary pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment using either perfluoropropane gas (C3F8) or silicone oil (SO) ...tamponade.
A retrospective chart analysis was made of 97 eyes from 92 patients with rhegmatogenous retinal detachment with no proliferative vitreoretinopathy that were treated with primary 23-gauge PPV. Eyes included in this were phakic (n = 28), pseudophakic (n = 41), or phakic eyes subject to simultaneous phacoemulsification, intraocular lens implantation, and PPV during primary rhegmatogenous retinal detachment repair (n = 28). Tamponade at the end of PPV was with either C3F8 (n = 65) or SO (n = 32). Success was defined as retinal reattachment at 1 year follow-up after a single procedure in eyes submitted to C3F8 injection; in eyes treated with SO injection, the success rate was defined as retina reattached 1 year after oil removal. Statistical comparisons were made between groups using chi-square, Fisher's exact test, Kruskal-Wallis, Mann-Whitney, and multivariate analysis. All eyes were operated by 2 experienced retina surgeons and had a minimum follow-up of 12 months.
The vitreoretinal redetachment rate in eyes subjected to C3F8 tamponade was significantly higher (28.6%) for phakic eyes (P = 0.011) compared with pseudophakic or phakic eyes that underwent to phacoemulsification and intraocular lens implantation (4.5%). Eyes in which SO was used at the end of the surgical procedure demonstrated a similar trend of higher reoperation rates in phakic eyes (28.6%) compared with pseudophakic or phakic eyes (8%) subjected to phacoemulsification and intraocular lens implantation; however, no statistically significant difference was observed (P = 0.201). No statistically significant differences were found between groups in relation to the number of tears (P = 0.863) and their location (inferior: P = 0.189, superior: P = 0.708, nasal: P = 0.756, and temporal: P = 0.08).
The success rates of primary 23-gauge PPV with either C3F8 or SO tamponade in pseudophakic eyes with rhegmatogenous retinal detachment was higher than the same procedure performed in phakic eyes. Still, the retrospective and limited data presented is too preliminary to suggest or recommend that practitioners perform simultaneous combined cataract surgery with retinal detachment and requires further studies in a larger and prospective design to confirm these present findings.
Purpose
To test the applicability of the acai dye at a 25% concentration for identifying the posterior hyaloids and internal limiting membranes (ILMs) during pars plana vitrectomy (PPV) in human eyes ...with macular holes (MHs).
Methods
This study included 25 patients with chronic idiopathic MHs. The exclusion criteria included glaucoma, previous significant ocular conditions, and previous ocular surgeries except uncomplicated cataract. Ten surgeons performed 23-gauge four-port PPV, phacoemulsification, posterior hyaloid detachment, ILM peeling guided by dye staining, and perfluoropropane injection. The patients remained prone for 5 days postoperatively. The patients were evaluated postoperatively after 1, 30, and 180 days. The surgeons completed a questionnaire regarding the dye’s staining abilities.
Results
The posterior hyaloids and ILMs stained purple in all eyes. The final best-corrected visual acuity improved significantly (
p <
0.001) from preoperatively (1.37 ± 0.29) to 180 days postoperatively (1.05 ± 0.43). The MHs closed in 76% of eyes.
Conclusion
The acai dye at a 25% concentration identified posterior hyaloids and ILMs during PPVs in humans. Dye toxicity was unlikely.
This case report describes a 19-year-old Caucasian man presented with decreased visual acuity in the right eye for 3 months. Dilated funds exam revealed optic disk pit associated with serous macular ...detachment. Optical coherence tomography identified communication between the optic disk pit and the macular serous detachment, and optical coherence tomography angiography displayed a subfoveal area suggestive of subfoveal choroidal neovascularization. However, there was no evidence of leakage in the fluorescein angiogram and no evidence of choroidal neovascularization in optical coherence tomography in the area corresponding to the suspicious subfoveal choroidal neovascularization. The patient underwent 23-gauge pars plana vitrectomy in the right eye. Six weeks after surgery, multimodal imaging was repeated and there was near-complete resorption of the subretinal fluid. Optical coherence tomography angiography signal superimposed on optical coherence tomography B-scan also demonstrated normal choriocapillaris signal throughout the macula. In conclusion, optical coherence tomography angiography may produce artifacts in optic disk pit maculopathy that simulate choroidal neovascularization.
The main drawback for the use of heavy silicone oil (HSO) Oxane HD is the difficulties it presents during removal. It differs from conventional silicone oil removal because it progressively ...concentrates in the posterior pole during the removal because of its heavier than water density. We describe a technique to facilitate proper HSO Oxane HD removal and minimize residual posterior bubbles and intraoperative complications. We describe our pearls for removing HSO to obtain the optimal results. A concern associated with HSO is the difficulty it presents when it is removed. However, this can be overcome by appropriate modification of surgical techniques during removal to limit intraoperative complications.
Role of Vital Dyes in Chromovitrectomy Bergamo, Vinicius C; Caiado, Rafael R; Maia, André ...
Asia-Pacific journal of ophthalmology,
01/2021, Letnik:
10, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Chromovitrectomy, the intraocular application of dyes to assist visualization of preretinal tissues during vitreoretinal surgery, was introduced to avoid ocular complications related to internal ...limiting membrane peeling, inadequate removal of the vitreous, and incomplete removal of epiretinal membranes. Since 2000, chromovitrectomy has become a popular approach among vitreoretinal specialists. The first vital dye used in chromovitrectomy, indocyanine green, facilitated identification of the fine and transparent internal limiting membrane. Following indocyanine green, trypan blue was introduced to identify epiretinal membranes, and triamcinolone acetonide stained the vitreous well. Recently, additional natural dyes such as lutein and anthocyanin from the açaí fruit have been proposed for intraocular application during vitrectomy. The main goal of this review was to study the role of vital stains in chromovitrectomy and report the latest findings in the literature.
Retinal pharmacotherapy has gained great importance for the treatment of various retinal diseases. An increasing number of drugs have been constantly released into the market, especially for wet ...age-related macular disease and diabetic macular edema. In this review, the issues concerning the toxicity of current and new classes of drugs are discussed.
An extensive search of the literature was performed to review various aspects of drug toxicity in retinal pharmacotherapy. The different major classes of drugs, such as corticosteroids, antibiotics, antimetabolites, antineoplastic agents, monoclonal antibodies (mAbs), nonsteroidal anti-inflammatory drugs, enzymes, fibrinolytics, miscellaneous anti-inflammatory and antiangiogenic agents, as well as toxicity unrelated to the drug were identified and discussed.
Corticosteroids like fluocinolone, dexamethasone or triamcinolone at low dose cause little damage to the retina, but at high doses signs of toxicity have been well documented. Complications like cataract and glaucoma are quite common with corticosteroids. Aminoglycosides showed differences in the type and doses associated with toxic reactions, thereby the following order of toxicity can be described (from most toxic to least toxic): gentamicin > netilmicin = tobramycin > amikacin = kanamycin. Vancomycin at the usual dose of 1 mg is not toxic to the retina, while further studies are necessary in order to clarify the safety of new-generation quinolones. 5-Fluorouracil has been shown to be nontoxic to the retina after an injection of 2.5 mg in animals. mAbs like ranibizumab and bevacizumab were demonstrated to be safe to the retina in cell culture, animals and humans at high doses. The exact biocompatibility of nonsteroidal anti-inflammatory agents like diclofenac needs further evaluation. Preservatives like benzyl alcohol and changes in pH or osmolarity exert an influence on the toxic effects of intravitreally applied drugs.
A great number of drugs are now used mainly intravitreally without relevant retinal toxicity.
PDF
