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Topic Review
Oxidative Stress in Retinal Dystrophies
Retinal cell survival requires an equilibrium between oxygen, reactive oxygen species, and antioxidant molecules that counteract oxidative stress damage. Oxidative stress alters cell homeostasis and elicits a protective cell response, which is most relevant in photoreceptors and retinal ganglion cells, neurons with a high metabolic rate that are continuously subject to light/oxidative stress insults. Any alteration on the retinal cell mechanisms to respond to oxidative stress injuries results in cell damage and apoptosis. Therefore, antioxidants agents, modulators of gene expression and inducers of cytoprotective signaling pathways may be used as potential therapies to ameliorate phenotypic symptoms in multifactorial and rare retinal dystrophies associated to oxidative stress injuries.
  • 900
  • 22 Sep 2021
Topic Review
Stem Cell Therapies in AMD
Age-related macular degeneration (AMD) is a highly prevalent irreversible impairment in the elderly population worldwide. Stem cell therapies have been considered potentially viable for treating AMD through the direct replacement of degenerated cells or secretion of trophic factors that facilitate the survival of existing cells. 
  • 896
  • 31 May 2021
Topic Review
Nano-Based DDS for Anterior Segment Diseases
The eye is a delicate and complex organ protected by anatomical barriers that limit the bioavailability and residence time of topically administered drugs. Polymeric nano-based drug delivery systems (DDS) have been developed to address this challenge and improve therapeutic outcomes. Biodegradable polymers are often used in these DDS to minimize adverse effects and control the release of different loaded drugs.
  • 894
  • 12 May 2023
Topic Review
Uveal Melanoma Tumors
Uveal melanoma (UM), a rare form of melanoma, is the most common intraocular cancer in adults.
  • 891
  • 26 Oct 2021
Topic Review
Uveal Melanomas
Traditionally, it has been thought that metastatic spread in uveal melanoma (UM) and dissemination occurs prior to presentation and that treatment of the primary tumor does not change outcome. However, it seems as though small UM tumours can not only be lethal with high risk monosomy 3 mutations, treated at an earlier time point at a smaller stage seems to improve mortality outcomes. 
  • 885
  • 22 Sep 2021
Topic Review
Role of Microaneurysms in Diabetic Macular Edema
Microaneurysms (MAs), a characteristic feature in diabetic retinopathy (DR) and diabetic macular edema (DME), can be detected by fluorescein angiography, optical coherence tomography (OCT) and OCT angiography. These instrumental analyses demonstrated a geographic and functional association between MA and ischemic areas. MA turnover, the production and loss of MA, reflects the activity of DME and DR. Several cytokines are involved in the pathogenesis of MAs, which is characterized by pericyte loss and endothelial cell proliferation in a vascular endothelial growth factor (VEGF)-dependent or -independent manner. Ischemia and MAs localized in the deep retinal layers are characteristic of refractory DME cases. Even in the current anti-VEGF era, laser photocoagulation targeting MAs in the focal residual edema is still an effective therapeutic tool, but it is necessary to be creative in accurately identifying the location of MAs and performing highly precise and minimally invasive coagulation. MAs play a distinctive and important role in the pathogenesis of the onset, progression of DR and DME, and response to anti-VEGF treatment. Further research on MA is significant not only for understanding the pathogenesis of DME but also for improving the effectiveness of treatment.
  • 885
  • 03 Apr 2023
Topic Review
Research Trends and Hotspots of Retinal OCT
Optical coherence tomography (OCT) is a widely used technology for high-resolution and cross-sectional imaging of tissues by measuring backscattered light. The emergence of optical coherence tomography (OCT) has sparked great interest in retinal research.
  • 885
  • 28 Sep 2022
Topic Review
Basics of Ocular Immunology
Ocular infectious diseases are an important cause of potentially preventable vision loss and blindness. Bacteria and viruses represent the more common causes of ocular infections worldwide and can affect nearly any anatomical part of the eye.
  • 879
  • 18 Aug 2023
Topic Review
Cannabineyed
The word cannabineyed refers to endocannabinoid system (ECS) physiology, dysregulation and modulation in the context of ocular and periocular tissues and structures. It derives by placing the word eye into the original one, cannabinoid. Specifically, the endocannabinoid system (ECS) is a complex regulatory system, highly conserved among vertebrates. It has been widely described in nearly all human tissues. In the eye, the ECS expression has been demonstrated both in the anterior and in the posterior segment. In this context, the ECS is believed to play a pivotal role in the modulation of the local inflammatory state as well as in the regulation of tissue repair and fibrosis, neo-angiogenesis, pain perception, intraocular pressure (IOP) control and neuroprotection.
  • 875
  • 12 Feb 2021
Topic Review
Advancements in Glaucoma Diagnosis
The progress of artificial intelligence algorithms in digital image processing and automatic diagnosis studies of the eye disease glaucoma has been growing and presenting essential advances to guarantee better clinical care for the population.
  • 871
  • 14 Mar 2024
Topic Review
Nutritional and Metabolic Imbalance in Keratoconus
Keratoconus (KC) is a progressive corneal degeneration characterized by structural changes consisting of progressive thinning and steepening of the cornea.
  • 867
  • 08 Mar 2022
Topic Review
Cell Therapy, Optogenetics and Exosomes for Retinitis Pigmentosa
Retinitis pigmentosa (RP) is a hereditary disease that causes the gradual degeneration of the photoreceptor cells in the retina, starting with the rods, leading to a progressive loss of vision over time. RP is the most prevalent form of inherited retinal dystrophy, affecting over 1.5 million individuals worldwide and significantly impacting both patients and society. RP is a primary cause of visual disability and blindness in people under 60 years old, and common symptoms include nyctalopia and gradual peripheral vision loss. If left untreated, RP can ultimately lead to complete blindness.
  • 861
  • 12 May 2023
Topic Review
Mycotic Keratitis
Mycotic or fungal keratitis (FK) is a sight-threatening infection of the cornea by filamentous fungi or yeasts. 
  • 855
  • 23 Apr 2021
Topic Review
Inherited Retinal Dystrophies
Inherited retinal dystrophies (IRDs) are a group of retinal disorders that cause progressive and severe loss of vision because of retinal cell death, mainly photoreceptor cells. IRDs include retinitis pigmentosa (RP), the most common IRD. IRDs present a genetic and clinical heterogeneity that makes it difficult to achieve proper treatment. The progression of IRDs is influenced, among other factors, by the activation of the immune cells (microglia, macrophages, etc.) and the release of inflammatory molecules such as chemokines and cytokines. Upregulation of tumor necrosis factor alpha (TNFα), a pro-inflammatory cytokine, is found in IRDs. This cytokine may influence photoreceptor cell death. Different cell death mechanisms are proposed, including apoptosis, necroptosis, pyroptosis, autophagy, excessive activation of calpains, or parthanatos for photoreceptor cell death. Some of these cell death mechanisms are linked to TNFα upregulation and inflammation. Therapeutic approaches that reduce retinal inflammation have emerged as useful therapies for slowing down the progression of IRDs.
  • 851
  • 22 Sep 2021
Topic Review
Treating Early and Advanced Stage of Diabetic Retinopathy
A brief overview about the advances in the experimental field on the treatment of early stages of diabetic retinopathy (ESDR), as well as the main gaps to be filled will be given. In addition, a critical view on the current clinical practice for treating advanced stages of diabetic retinopathy (ASDR) will be provided.
  • 848
  • 23 Aug 2022
Topic Review
Silicone Oil in Surgical Management of Endophthalmitis
Endophthalmitis represents one of the biggest diagnostic and therapeutic challenges in modern ophthalmology. It threatens all forms of intraocular surgery from intravitreal injections to corneal transplants and vitrectomies and it is discussed on all surgical consent forms. Silicone oil reduces the risk of postoperative retinal detachment, especially in case of undetected retinal breaks, produces compartmentalization of the eye, may lead to early visual recovery, allows laser photocoagulation, prevents severe postoperative hypotony and has antimicrobic activity due to an inhibitory effect for several species of pathogens. 
  • 846
  • 24 Oct 2022
Topic Review
Galactosemic Cataract
A galactosemic cataract is cataract which is associated with the consequences of galactosemia.
  • 846
  • 03 Nov 2022
Topic Review
A Brief Clinical Overview of Retinitis Pigmentosa
Retinitis pigmentosa (RP) is a hereditary disease that causes the degeneration of photoreceptor cells in the retina, starting with the rods, leading to a gradual loss of vision over time. RP is the most common type of inherited retinal dystrophy and affects over 1.5 million people worldwide, leading to a high burden on patients and society. Common symptoms of RP include nyctalopia and gradual loss of peripheral vision, which can ultimately lead to blindness. RP is one of the primary causes of visual disability and blindness in individuals under 60 years old.
  • 844
  • 12 May 2023
Topic Review
Biologics in Uveitis Treatment
Biological drugs, especially those targeting anti-tumour necrosis factor α (TNFα) molecule, have revolutionized the treatment of patients with non-infectious uveitis (NIU), a sight-threatening condition characterized by ocular inflammation that can lead to severe vision threatening and blindness. 
  • 842
  • 15 Mar 2023
Topic Review
Retromode Imaging in Age-Related Macular Degeneration
Retromode is a relatively new retinal-imaging technique that is based on the transillumination principle and is obtained with a scanning laser ophthalmoscope that uses light in the infrared spectrum. The laser light penetrates into the deep retinal layers and the choroid. Retromode images are captured with a laterally displaced aperture, and the detector captures only the scattered light. The result is a high-contrast pseudo-three-dimensional image. Age-related macular degeneration (AMD) is a disabling retinal disease. AMD is characterized in its early stage by small and intermediate drusen formation, while the signs of intermediate AMD are large drusen and/or pigmentary abnormalities. Late AMD has two forms, geographic atrophy, which is the advanced form of dry AMD, and wet AMD. Most of the lesions of AMD are located in the outer layers of the retina. This new imaging method can provide a glimpse of the deep retinal layers’ topographic changes in a non-invasive, fast, and effective way that can match the other imaging tools available. 
  • 841
  • 03 Apr 2023
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