OCT Features of the Donor Area in Autologous Retinal Transplant Surgery for Macular Hole.

Purpose: To describe the structural features of the autologous retinal transplant donor tissue area seen on optical coherence tomography (OCT). Methods: This observational prospective study included patients who had vitrectomy and autologous retinal graft surgery for a macular hole. OCT of the donor area was performed in the postoperative period after gas reabsorption (mean, 16.2 days ±9.8 [SD] after surgery; range, 7 to 28 days), and structural findings in the harvest area were recorded and analyzed. Results: Of the 12 eyes included in the series, most showed glial tissue or some migration of the inner nuclear layer (INL) in the donor area. Hyperreflective dots and epiretinal membranes were present in a few cases; 2 eyes showed denuded retinal epithelial pigment. Conclusions: OCT revealed changes in the donor area, predominantly filled with glial tissue, INL migration, and inflammatory signs, that mostly resolved during follow-up.

Autologous Retinal Transplant Repeat Surgery after Initial Graft Failure: A Case Report.

Autologous retinal transplant (ART) has become an increasingly explored surgical option for managing large chronic holes refractory to standard surgical treatments. However, management strategies for patients who already failed a previous ART are less well-understood. Here, we report on a case of a successful repeat retinal transplant for a refractory macular hole after a previously dislocated ART graft. Subretinal injection of balanced salt solution was used to partially elevate the macular hole and secure the edge of the harvested retinal graft under the edge of the macular hole in the second operation. Postoperatively, the patient developed intraretinal fluid within the retinal graft with an appearance similar to cystoid macular edema, which was controlled with topical steroids. In addition, two separate choroidal neovascular membranes along the subretinal injection sites were seen and treated with vascular endothelial growth factor downregulation. This case illustrates successful repeat ART surgery, but further optimization of ART surgical techniques is necessary to minimize ART's complication rate.

Angiogenesis and Anastomosis on Graft Retina after Autologous Retinal Transplantation.

Anastomosis on graft retina was studied after autologous retinal transplantation (ART) on 26 eyes with primary and refractory macular holes. Angiogenesis and anastomosis were seen in 35% of the eyes with successful ART, likely contributing to the survival of the transplanted retina.

Current management strategies for atypical macular holes.

This review evaluates the current surgical management options for refractory and atypical macular holes (MH) and proposes a treatment paradigm for approaching complex cases. A review of literature was performed to deliver a thorough discussion of the epidemiology and pathophysiology of MH as well as the historic evolution of surgical management strategies. With this context established, an update on recent surgical advances for management of large, chronic, and highly myopic MH is provided. New small MH may be adequately treated with pars plana vitrectomy, while those ≥300 µm should undergo internal limiting membrane (ILM) peel. For MH ≥400 µm with risk factors for failure, primary intervention should involve creation of an ILM flap and various methods of flap creation are discussed. For very large MH ≥700 µm or in refractory cases, autologous retinal transplants and other recently proposed procedures should be considered. While typical MHs enjoy high initial surgical success rates, atypical and refractory MH require additional intraoperative and postoperative considerations to maximize surgical success and optimize vision. With many techniques at the surgeon's disposal, patient selection becomes critical to improving outcomes.

3D Printing in Eye Care.

Three-dimensional printing enables precise modeling of anatomical structures and has been employed in a broad range of applications across medicine. Its earliest use in eye care included orbital models for training and surgical planning, which have subsequently enabled the design of custom-fit prostheses in oculoplastic surgery. It has evolved to include the production of surgical instruments, diagnostic tools, spectacles, and devices for delivery of drug and radiation therapy. During the COVID-19 pandemic, increased demand for personal protective equipment and supply chain shortages inspired many institutions to 3D-print their own eye protection. Cataract surgery, the most common procedure performed worldwide, may someday make use of custom-printed intraocular lenses. Perhaps its most alluring potential resides in the possibility of printing tissues at a cellular level to address unmet needs in the world of corneal and retinal diseases. Early models toward this end have shown promise for engineering tissues which, while not quite ready for transplantation, can serve as a useful model for in vitro disease and therapeutic research. As more institutions incorporate in-house or outsourced 3D printing for research models and clinical care, ethical and regulatory concerns will become a greater consideration. This report highlights the uses of 3D printing in eye care by subspecialty and clinical modality, with an aim to provide a useful entry point for anyone seeking to engage with the technology in their area of interest.

Autologous full-thickness retinal transplant for refractory large macular holes.

BACKGROUND: Despite the constant refinement of techniques and surgical aids, extremely large and refractory macular holes continue to have poor surgical outcomes with the current standard of care. The objective of the present study is to assess the anatomical and functional outcomes, as well as the structural change through time, of the optical coherence tomography of patients with refractory macular holes treated with a full-thickness autologous retinal transplant. METHODS: Prospective, case series. We include patients with a clinical diagnosis of refractory macular holes with a minimum diameter of at least 500 µm. All the patients had a comprehensive ophthalmological examination, which included a best-corrected visual acuity assessment, fundus examination, and optical coherence analysis. All the patients underwent a 23-gauge pars plana vitrectomy with a full-thickness retinal transplant and silicone oil tamponade (5000 cs<). Follow-up was done at 1, 3, 6, and 12 months. Statistical analysis was done with a test for repeated measurements and Bonferroni correction, with an alpha value of 0.05 for statistical significance and a Mann-Whitney U test for nonparametric continuous variables. RESULTS: We enrolled 13 eyes from 13 patients (mean age: 67.15 years) with refractory macular holes, with a mean base diameter of 1615.38 ± 689.19 µm and a minimum diameter of 964.08 ± 709.77 µm. The closure rate after 12 months of follow-up was 76.92%. Six patients with a closed macular hole at the end of the follow-up had complete recovery of the myoid/ellipsoid layer. The remaining showed a 44.9% reduction of the initial gap. Most patients formed a pseudofovea and normalization of the internal retinal layers. Despite a positive trend toward visual recovery (p = 0.034), after the correction of the alpha value, the change lost its statistical significance. During follow-up, one patient developed mild proliferative vitreoretinopathy and epiretinal membrane without anatomical or functional consequences. CONCLUSIONS: An autologous full-thickness retinal transplant may improve the anatomical and structural outcome of patients with refractory macular holes. The full safety profile of this new technique is still unknown. More studies are needed in order to assess functional changes through time.

Genetic Manipulation and Selection of Mouse Mesenchymal Stem Cells for Delivery of Therapeutic Factors In Vivo.

Bone marrow-derived mesenchymal stem cells (MSCs) hold great potential as an ex vivo cellular system for delivery of therapeutic proteins to the diseased or damaged central nervous system (CNS). This adult stem cell population has considerable translational potential for autologous transplantation due to lack of ethical concerns, accessibility, multipotent nature, and plasticity. Here we describe a methodology and outline a strategy using lentiviral vectors for producing lines of MSCs hypersecreting neurotrophic growth factors (e.g., brain-derived neurotrophic factor (BDNF) and/or glial cell line-derived neurotrophic factor (GDNF)) together with a reporter protein such as green fluorescent protein (GFP) that may be used for in vitro and in vivo neuroprotection bioassays. This approach provides exciting opportunities for basic research and proof-of-concept studies.

Therapeutic challenges to retinitis pigmentosa: from neuroprotection to gene therapy.

Syndromic retinitis pigmentosa (RP) is the result of several mutations expressed in rod photoreceptors, over 40 of which have so far been identified. Enormous efforts are being made to relate the advances in unraveling the patho-physiological mechanisms to therapeutic approaches in animal models, and eventually in clinical trials on humans. This review summarizes briefly the current clinical management of RP and focuses on the new exciting treatment possibilities. To date, there is no approved therapy able to stop the evolution of RP or restore vision. The current management includes an attempt at slowing down the degenerative process by vitamin supplementation, trying to treat ocular complications and to provide psychological support to blind patients. Novel therapeutic may be tailored dependant on the stage of the disease and can be divided in three groups. In the early stages, when there are surviving photoreceptors, the first approach would be to try to halt the degeneration by correction of the underlying biochemical abnormality in the visual cycle using gene therapy or pharmacological treatment. A second approach aims to cope with photoreceptor cell death using neurotrophic growth factors or anti-apoptotic factors, reducing the production of retino-toxic molecules, and limiting oxidative damage. In advanced stages, when there are few or no functional photoreceptors, strategies that may benefit include retinal transplantation, electronic retinal implants or a newly described optogenetic technique using a light-activated channel to genetically resensitize remnant cone-photoreceptor cells.