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Topic Review
Cataracts
A cataract is an ophthalmic disorder characterized by the opacification of the lens and occurs commonly in older people. Age-related cataract is a significant cause of blindness affecting the quality of life worldwide. An imbalance between oxidative stress and antioxidant potential of ocular tissue is considered responsible for structural modifications of crystallins, the protein constituents of the lens, which eventually leads to cataracts. Lutein and zeaxanthin are two major carotenoids which are concentrated in the human lens. Many preclinical and clinical studies provide compelling evidence for a protective role of dietary carotenoids in age-related cataracts.
  • 4.8K
  • 28 Sep 2021
Topic Review
Intraretinal Fluid Pattern Characterization
The accumulation of fluids in the retinal layers is one of the main causes of blindness in developed countries. The main strategy for its study and diagnosis is through the use of Optical Coherence Tomography (OCT) images. This allows experts to observe the layers of the retina in a cross-sectional view. Commonly, for the analysis of these accumulations by means of computer diagnostic support systems, precise segmentation strategies are employed.
  • 3.0K
  • 22 Apr 2021
Topic Review Peer Reviewed
Intraocular Pressure during Spaceflight and Risk of Glaucomatous Damage in Prolonged Microgravity
Microgravity introduces diverse pathological and various physiological changes to the human body, including intraocular pressure. Astronauts may develop a constellation of symptoms and signs including optic disc edema, choroidal folds, and a hyperopic shift from the flattening of the globe. These ocular findings have been collectively termed spaceflight-associated neuro-ocular syndrome (SANS). SANS is a condition that is unique to long-duration spaceflight. The precise pathogenesis of SANS remains ill-defined, but several hypotheses have been proposed that may be influenced by intraocular pressure. Countermeasures for SANS research also include techniques that impact intraocular pressure. In this article, we discuss intraocular pressure during spaceflight, the translaminar pressure gradient, SANS and potential SANS countermeasures, and the potential for glaucomatous damage during spaceflight.
  • 2.7K
  • 19 Oct 2023
Topic Review
Dissociated Optic Nerve Fiber Layer
Dissociated optic nerve fiber layer (DONFL) appearance is characterized by dimpling of the fundus when observed after vitrectomy with the internal limiting membrane (ILM) peeling in macular diseases. However, the cause of DONFL remains largely unknown. Optical coherence tomography (OCT) findings have indicated that the nerve fiber layer (NFL) and ganglion cells are likely to have been damaged in patients with DONFL appearance. Since DONFL appearance occurs at a certain postoperative period, it is unlikely to be retinal damage directly caused by ILM peeling because apoptosis occurs at a certain period after tissue damage and/or injury. However, it may be due to ILM peeling-induced apoptosis in the retinal tissue. Anoikis is a type of apoptosis that occurs in anchorage-dependent cells upon detachment of those cells from the surrounding extracellular matrix (i.e., the loss of cell anchorage). The anoikis-related proteins βA3/A1 crystallin and E-cadherin are reportedly expressed in retinal ganglion cells. 
  • 2.4K
  • 05 Mar 2021
Topic Review
Silver in Ophthalmology
The use of silver preparations in medicine is becoming increasingly popular. 
  • 2.3K
  • 15 Apr 2021
Topic Review
Episcleritis and Scleritis
Episcleritis and scleritis are the most common ocular inflammatory manifestation of rheumatoid arthritis.
  • 2.2K
  • 07 Jun 2021
Topic Review
Cat-Scratch Disease’s Neuro-Ophthalmological Effects
Cat-scratch disease is an illness caused by Bartonella henselae that occurs as a result of contact with an infected kitten or dog, such as a bite or scratch. It is more prevalent in children and young adults, as well as immunocompromised individuals. Among the ophthalmologic disorders caused by cat-scratch disease in humans, Parinaud oculoglandular syndrome, uveitis, vitritis, retinitis, retinochoroiditis and optic neuritis are the most prevalent. The neurological disorders caused by cat-scratch disease in humans include encephalopathy, transverse myelitis, radiculitis, and cerebellar ataxia.
  • 2.2K
  • 21 Feb 2022
Topic Review
Retinal Vein Occlusion
Retinal vein occlusion (RVO) is the second most common retinal vascular disorder next to diabetic retinopathy. 
  • 2.0K
  • 22 Sep 2021
Topic Review
Iridoschisis
Iridoschisis is a rare condition defined as a separation of the anterior iris stroma from the posterior stroma and muscle layers. A variety of ocular pathologies can coexist with iridoschisis, but in most cases the causal relationship, if any, is unclear. Glaucoma, primarily angle-closure glaucoma, is the most often described condition concomitant to iridoschisis. Other ocular abnormalities found relatively often in iridoschisis patients include cataract, lens subluxation and corneal abnormalities. Iridoschisis is plausibly a multifactorial disease. A patient diagnosed with iridoschisis should be screened for potential glaucoma, corneal and lens abnormalities. Iridoschisis may pose a challenge for both an ophthalmologist in an outpatient setting and an ophthalmic surgeon.
  • 1.9K
  • 10 Nov 2020
Topic Review
Age Related Macular Degeneration
Age related macular degeneration (AMD) is a disease associated with aging of the central area of the retina called the macula. It results in a progressive loss of central vision.In western countries, AMD is the leading cause of severe vision loss in people over the age of 50. About 25 to 30 million people suffer from AMD. Due to the aging of the population, this figure could double in the next 35 years.
  • 1.8K
  • 09 Nov 2020
Topic Review
Choroidal Imaging Findings in CSCR
Central serous chorioretinopathy (CSCR) is a chorioretinal disease affecting mostly middle-age males. It is marked by the serous detachment of the neurosensory layer at the macula. This review of the literature provides a framework of the current characteristic/relevant imaging findings of CSCR. Although the pathogenesis of CSCR is unclear, the choroid plays a major role and its changes are fundamental to the diagnosis and treatment of CSCR.  Choroidal imaging has advanced the diagnosis of CSCR. This has led to numerous imaging biomarkers like CVI, CT, and hyperreflective dots for early detection and possible prognostication of CSCR. More techniques like wide-field scans and en face imaging are being employed to characterize the choroid in CSCR. 
  • 1.7K
  • 22 Sep 2021
Topic Review
Ocular Autonomic Nervous System
The autonomic nervous system (ANS) confers neural control of the entire body, mainly through the sympathetic and parasympathetic nerves. Several studies have observed that the physiological functions of the eye (pupil size, lens accommodation, ocular circulation, and intraocular pressure regulation) are precisely regulated by the ANS. Almost all parts of the eye have autonomic innervation for the regulation of local homeostasis through synergy and antagonism. With the advent of new research methods, novel anatomical characteristics and numerous physiological processes have been elucidated.
  • 1.6K
  • 19 Jan 2022
Topic Review
Vitamin A in Retinal Diseases
Vitamin A is an essential fat-soluble vitamin that occurs in various chemical forms. It is essential for several physiological processes. Either hyper- or hypovitaminosis can be harmful. One of the most important vitamin A functions is its involvement in visual phototransduction, where it serves as the crucial part of photopigment, the first molecule in the process of transforming photons of light into electrical signals. In this process, large quantities of vitamin A in the form of 11-cis-retinal are being isomerized to all-trans-retinal and then quickly recycled back to 11-cis-retinal. Complex machinery of transporters and enzymes is involved in this process (i.e., the visual cycle). Any fault in the machinery may not only reduce the efficiency of visual detection but also cause the accumulation of toxic chemicals in the retina. 
  • 1.6K
  • 10 Feb 2022
Topic Review
Anterior Chamber Angle Assessment Techniques
This review summarizes the last findings in Anterior Chamber Angle evaluation, focusing on new instruments and their application to the clinical practice. Special attention will be given to the comparison between these new techniques and traditional slit-lamp gonioscopy.
  • 1.6K
  • 11 Dec 2020
Topic Review
Single Vision Spectacles in Myopia
Myopia is caused by excessive eye growth. Single vision lenses can fully correct the myopic refractive error. Moreover, single vision lenses were investigated as myopia control method and control effects were compared between full-, over-, under- and un-correction. Study results are controversial, however, no beneficial effect of over-, under- and un-correction of myopia were found. Considering ethical reasons in children as well, current clinical advice is directed towards full-correction of myopia if single vision lenses are the correction method of choice.
  • 1.6K
  • 27 Aug 2020
Topic Review
Diabetic Retinopathy
Diabetic retinopathy (DR) is the most frequent microvascular complication of long-term diabetes and the most common cause of blindness, increasing morbidity in the working-age population. The most effective therapies for these complications include laser photocoagulation and anti-vascular endothelial growth factor (VEGF) intravitreal injections. However, laser and anti-VEGF drugs are untenable as a final solution as they fail to address the underlying neurovascular degeneration and ischemia. Regenerative medicine may be a more promising approach, aimed at the repair of blood vessels and reversal of retinal ischemia. Stem cell and tissue engineering therapy have introduced a novel way to reverse the underlying ischemia present in microvascular complications in diseases such as diabetes. 
  • 1.5K
  • 30 Oct 2020
Topic Review
Autophagy in Eye Diseases
Autophagy is a catabolic process that ensures homeostasis in the cells of our organism. It plays a crucial role in protecting eye cells against oxidative damage and external stress factors. Ocular pathologies of high incidence, such as age-related macular degeneration, cataracts, glaucoma, and diabetic retinopathy are of multifactorial origin and are associated with genetic, environmental factors, age, and oxidative stress, among others; the latter factor is one of the most influential in ocular diseases, directly affecting the processes of autophagy activity. 
  • 1.4K
  • 23 Apr 2021
Topic Review
Nanotechnology for Eye Topical Drug Delivery
Topical drug delivery is one of the most challenging aspects of eye therapy. Eye drops are the most prevalent drug form because they are convenient and easy to apply by patients. However, conventional drug formulations are usually characterized by short retention time in the tear film, insufficient contact with epithelium, fast elimination, and difficulties in overcoming ocular tissue barriers. Not more than 5% of the total drug dose administered in eye drops reaches the interior ocular tissues. Drug-loaded nanoparticles/hydrogels do not enter cells via diffusion. The endocytosis pathway is related to the penetration of drug-loaded nanoparticles/hydrogels into the cell. The interactions between the nanoparticles and the cell membrane generate forces of different origins and lead to the membrane wrapping of the nanoparticles followed by cellular uptake.
  • 1.4K
  • 24 Dec 2021
Topic Review
Farnsworth-Munsell 100 Hue Test
The Farnsworth-Munsell 100 Hue Color Vision test is a test of the human visual system often used to test for color blindness. The system was developed by Dean Farnsworth in the 1940s and it tests the ability to isolate and arrange minute differences in various color targets with constant value and chroma that cover all the visual hues described by the Munsell color system. There are several variations of the test, one featuring 100 color hues and one featuring 15 color hues. Originally taken in an analog environment with physical hue tiles, the test is now taken from computer consoles. An accurate quantification of color vision accuracy is particularly important to designers, photographers and colorists, who all rely on accurate color vision to produce quality content.
  • 1.3K
  • 01 Dec 2022
Topic Review
Retinal Organization
The retinal arhitecture is similar across all vertebrates despite the morphological and functional peculiarities. The retina is composed of two main parts: the single-layred retinal pigment epithelium and the multilayred neuroretina which includes a number of neuronal and glial cell types. Homeobox genes from different classes are accepted as critical for eye field specification and retinal cells type differentiation by a broad array of loss- or gain-of-function models. Among these genes are some that are known to cause inherited retinal diseases (IRDs) that disturb the formation, function, and survival of rod and cone photoreceptors, ganglion cells, or retinal pigment epithelial cells [4,6–8]. The advances in the field of genetics and high-throughput next-generation sequencing and cell technologies allow for deepening of knowledge of the genetic basis of inherited retinal diseases (IRDs), as well as improve their diagnostics and therapy.
  • 1.3K
  • 22 Sep 2021
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