The cornea is unique because of its complete avascularity. Corneal neovascularization (CNV) can result from a variety of etiologies including contact lens wear; corneal infections; and ocular surface diseases due to inflammation, chemical injury, and limbal stem cell deficiency. Management is focused primarily on the etiology and pathophysiology causing the CNV and involves medical and surgical options. Because inflammation is a key factor in the pathophysiology of CNV, corticosteroids and other anti-inflammatory medications remain the mainstay of treatment. Anti-VEGF therapies are gaining popularity to prevent CNV in a number of etiologies. Surgical options including vessel occlusion and ocular surface reconstruction are other options depending on etiology and response to medical therapy. Future therapies should provide more effective treatment options for the management of CNV.

The epithelial cell layer that covers the surface of the cornea provides a protective barrier while maintaining corneal transparency. The rapid and effective turnover of these epithelial cells depends, in part, on the limbal epithelial stem cells (LESCs) located in a specialized microenvironment known as the limbal niche. Many disorders affecting the regeneration of the corneal epithelium are related to deficiency and/or dysfunction of LESCs and the limbal niche. Current approaches for regenerating the corneal epithelium following significant injuries such as burns and inflammatory attacks are primarily aimed at repopulating the LESCs. This review summarizes and assesses the clinical feasibility and efficacy of current and emerging approaches for reconstruction of the limbal niche. In particular, the application of mesenchymal stem cells along with appropriate biological scaffolds appear to be promising strategies for long-term revitalization of the limbal niche.

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Purpose of Review The aim of this review is to describe the underlying mechanisms of corneal epithelial homeostasis in addition to illustrating the vital role of the limbal epithelial stem cells (LESCs) and the limbal niche in epithelial regeneration and wound healing. Recent Findings The shedded corneal epithelial cells are constantly replenished by the LESCs which give rise to epithelial cells that proliferate, differentiate and migrate centripetally. While some recent studies have proposed that epithelial stem cells may also be present in the central cornea, the predominant location for the stem cells is the limbus. The limbal niche is the specialized micro-environment consisting of cells, extra-cellular matrix and signaling molecules that are essential for the function of LESCs. Disturbances to limbal niche can result in LESC dysfunction, therefore, limbal stem cell deficiency should also be considered a limbal niche deficiency. Current and in–development therapeutic strategies are aimed at restoring the limbal niche, by medical and/or surgical treatments, administration of trophic factors and cell based therapies. Summary The corneal epithelium is constantly replenished by LESCs that are housed within the limbal niche. The limbal niche is the primary determinant of the LESC function and novel therapeutic approaches should be focused on regeneration of this microenvironment.

Stickler Syndrome (SS) is a significant cause of retinal blindness in children. The immediate cause of blindness is retina detachment from giant retinal tear (GRT). It is frequently diagnosed late and the giant retinal tear (GRT) may be complicated by high-grade proliferative vitreoretinopathy (PVR). The surgery for the combined GRT with PVR has limited structural results and the vision mainly remains impaired. In order to improve the visual outcomes, we propose an organized program oriented toward early diagnosis and surveillance. Adding an effective prophylaxis may maintain normal vision in a high percent of patients. The critical diagnostic moments for this program are prenatal and at birth. The tools include a directed history, general physical exam and advanced ophthalmologic exam looking for the particular features of SS. Some features may need advanced skills transfer, because they are not reliably taught in retina fellowships. Much of this program requires a partnership with obstetricians, pediatricians, neonatologists and geneticists. Finally, we review the evidence regarding prophylaxis and discuss our approach in the absence of guidance from a randomized clinical trial.

A novel, stable, functionalized, and targeted graphene-based drug delivery system for smart transportation of hydrophobic agents is introduced.

Background Lowe syndrome is a rare X-linked disease that is characterized by renal dysfunction, developmental delays, congenital cataracts and glaucoma. Mutations in the oculocerebral renal syndrome of Lowe ( OCRL) gene are found in Lowe syndrome patients. Although loss of vision is a major concern for families and physicians who take care of Lowe syndrome children, definitive cause of visual loss is still unclear. Children usually present with bilateral dense cataracts at birth and glaucoma, which occurs in more than half of cases, either concurrently or following cataract surgery. Materials and methods A retrospective review was conducted on the prevalence and characteristics of ocular findings among families of patients with Lowe syndrome with 137 uniquely affected individuals. Results Of 137 patients, all had bilateral congenital cataracts. Nystagmus was reported in 69.3% of cases, glaucoma in 54.7%, strabismus in 35.0%, and corneal scar in 18.2% of patients. Glaucoma was reported as the most common cause of blindness (46%) followed by corneal scars (41%). Glaucoma occurred in 54.7% of patients and affected both eyes in the majority of cases. Of these patients, 55% underwent surgery for glaucoma, while the remaining patients used medications to control their eye pressure. Timolol and latanoprost were the most commonly used medications. Although trabeculectomy and goniotomy are commonly used for pressure management, aqueous tube shunts had the best outcomes. Conclusion Ocular manifestations in individuals with Lowe syndrome and carriers with OCRL mutation are reported which may help familiarize clinicians with the ocular manifestations and management of a rare and complex syndrome.

Purpose of review In this article, we review the indications and latest management of high-risk penetrating keratoplasty. Recent findings Despite the immune-privilege status of the cornea, immune-mediated graft rejection still remains the leading cause of corneal graft failure. This is particularly a problem in the high-risk graft recipients, namely patients with previous graft failure due to rejection and those with inflamed and vascularized corneal beds. A number of strategies including both local and systemic immunosuppression are currently used to increase the success rate of high-risk corneal grafts. Moreover, in cases of limbal stem cell deficiency, limbal stem cells transplantation is employed. Summary Corticosteroids are still the top medication for prevention and treatment in cases of corneal graft rejection. Single and combined administration of immunosuppressive agents e.g. tacrolimus, cyclosporine and mycophenolate are promising adjunctive therapies for prolonging graft survival. In the future, cellular and molecular therapies should allow us to achieve immunologic tolerance even in high-risk grafts.