Blue Light-Ocular and Systemic Damaging Effects: A Narrative Review.

Light is a fundamental aspect of our lives, being involved in the regulation of numerous processes in our body. While blue light has always existed in nature, with the ever-growing number of electronic devices that make use of short wavelength (blue) light, the human retina has seen increased exposure to it. Because it is at the high-energy end of the visible spectrum, many authors have investigated the theoretical harmful effects that it poses to the human retina and, more recently, the human body, given the discovery and characterization of the intrinsically photosensitive retinal ganglion cells. Many approaches have been explored, with the focus shifting throughout the years from examining classic ophthalmological parameters, such as visual acuity, and contrast sensitivity to more complex ones seen on electrophysiological assays and optical coherence tomographies. The current study aims to gather the most recent relevant data, reveal encountered pitfalls, and suggest future directions for studies regarding local and/or systemic effects of blue light retinal exposures.

Topical Treatment for Retinal Degenerative Pathologies: A Systematic Review.

The topical administration of medicines is the preferred route in ocular therapy, at least for the anterior segment of the eye. However, the eye's inherent functional and biological barriers all work against the active pharmaceutical ingredient (API) to efficiently reach the targeted retinal structures. The main objective of this article is to offer a systematic review of the scientific literature in recent years, focusing on the latest developments of topical treatment intended for retinal degenerative diseases. Database search returned 102 clinical studies, focused on topical treatment for age macular degeneration, macular edemas (in diabetic retinopathy, surgery related or in retinal dystrophies) or glaucoma. After the exclusion of low-powered studies and those combining vitreo-retinal surgery, 35 articles remained for analysis. Currently, the topical treatment of retinal degenerative diseases is limited by the difficulty to deliver effective drug concentrations to the posterior eye structures. However, in the case of drug classes like NSAIDs, the presence of certain molecular and metabolic features for specific representatives makes the topical administration currently feasible in several clinical contexts. For other drug classes, either a fine-tuning of the API's pharmacokinetic profile or the use of more advanced formulation strategies, such as rationally designed nanostructured drugs and vehicles, crystalline polymorphs or supramolecular complexes, could bring the much awaited breakthrough for a more predictable and controlled delivery towards the retinal structures and could eventually be employed in the future for the development of more effective ways of delivering drugs to the posterior eye, with the ultimate goal of improving their clinical efficacy.

Topical nanodelivery system of lutein for the prevention of selenite-induced cataract.

Cataracts are responsible for half of the world blindness, surgery being the only viable treatment. Lutein, a naturally occurring carotenoid in the eye, has the potential to reduce cataract progression by protecting the eye from photo-oxidative stress. To restore the eye's natural line of defense against photo-oxidative stress, a formulation was developed using zein and poly(lactic-co-glycolic acid) nanoparticles (NPs) embedded in an optimized bioadhesive thermosensitive gel for the delivery of lutein via topical application. Cataracts were induced in Crl:WI rats via selenite injection at 13 days post-partum, followed by 7 days of treatment with free lutein or lutein-loaded NPs administered orally or topically. Cataract severity was significantly reduced in rats treated with topical applications of lutein-loaded NPs compared to the positive control, while no significant differences were observed in rats treated with other lutein formulations including oral and topically applied free lutein.

Spiritual and religious perspectives in persons with visual impairment due to age-related macular degeneration.

Introduction: Age-related macular degeneration (AMD) is one of the global leading causes of severe vision loss. Patients suffering from AMD face complex spiritual and mental challenges that have an impact on the course of their disease, their quality of life, and their relationship with their surroundings. Methods: A survey was carried out using a 21-item questionnaire between August 2020 and June 2021 among 117 patients from different countries to investigate how spirituality, religion, and their way of practicing them affected the experiences and daily lives of patients suffering from AMD, and whether it helped them cope with the disease. Results: Our study concluded that spirituality and religion are important factors that facilitate patients' ability to cope with a progressive degenerative disease such as AMD. Patients who are religious are more at peace with having AMD. Practices that contribute to patients being at peace in accepting the disease are regular prayers or meditation. Spirituality and religion are important components that promote a healthier and happier emotional state and mental wellbeing. In particular, by believing that death is not the end, patients feel more hopeful, which helps in their adjustment to a seemingly hopeless health condition. A significant number of AMD patients desire to talk about God with the medical staff. The profile of such patients could be those believing in a higher power, praying often, participating in religious services, being worried about the loss of vision, and needing assistance in daily life. Discussion: An interdisciplinary and multidimensional team of medical health professionals including mental health workers and chaplains can be of great value in managing persons with AMD.

Identifying Optical Coherence Tomography Markers for Multiple Sclerosis Diagnosis and Management.

BACKGROUND: Multiple sclerosis (MS) is a common neurological disease affecting the optic nerve, directly or indirectly, through transsynaptic axonal degeneration along the visual pathway. New ophthalmological tools, arguably the most important being optical coherence tomography (OCT), could prove paramount in redefining MS diagnoses and shaping their follow-up protocols, even when the optic nerve is not involved. METHODS: A prospective clinical study was conducted. In total, 158 eyes from patients previously diagnosed with relapsing remitting MS (RRMS)-with or without optic neuritis (ON), clinically isolated syndrome (CIS) with or without ON, and healthy controls were included. Each patient underwent an ophthalmologic exam and OCT evaluation for both eyes (a posterior pole analysis (PPA) and the optic nerve head radial circle protocol (ONH-RC)). RESULTS: The macular retinal thickness (the 4 × 4, respectively, 2 × 2 grid) and thickness of the peripapillary retinal nerve fiber layer (pRNFL) were investigated. Various layers of the retina were also compared. Our study observed significant pRNFL thinning in the RRMS eyes compared to the control group, the pRNFL atrophy being more severe in the RRMS-ON eyes than the RRMS-NON eyes. In the ON group, the macular analysis showed statistically significant changes in the RRMS-ON eyes when compared only to the CIS-ON eyes, regarding decreases in the inner plexiform layer (IPL) thickness and inner nuclear layer (INL) on the central 2 × 2 macular grid. The neurodegenerative process affected both the inner retina and pRNFL, with clinical damage appearing for the latter in the following order: CIS-NON, CIS-ON, RRMS-NON, and RRMS-ON. In the presence of optic neuritis, SMRR patients presented an increase in their outer retina thickness compared to CIS patients. CONCLUSIONS: To differentiate the MS patients from the CIS patients, in the absence of optic neuritis, OCT Posterior Pole Analysis could be a useful tool when using a central 2 × 2 sectors macular grid. Retinal changes in MS seem to start from the fovea and spread to the posterior pole. Finally, MS could lead to alterations in both the inner and outer retina, along with pRNFL.

The key role of the ophthalmologist in diagnosing botulism: two case reports.

Introduction: Botulinum toxin, the strongest known neurotoxin, is the cause of a rare fatal neuroparalytic disease characterized by the so-called "four Ds": diplopia, dysarthria, dysphagia, dry mouth. If left untreated, botulism may cause paralysis of the respiratory muscles, impairing the respiratory function which can ultimately lead to death. Case report: We describe the cases of two patients who presented, two years apart, with similar ocular symptoms such as blurred vision due to accommodation palsy, diplopia, accompanied by xerostomia and swallowing disorders, which were further confirmed as botulism. Both cases had a similar clinical presentation of the intoxication and a positive response to treatment with botulinum antitoxin, while only the first case had a laboratory confirmation of the disease. Conclusions: The key to diagnose botulism correctly is based on high clinical suspicion and requires a medical multidisciplinary approach and urgent specific treatment. Ophthalmology specialists must be aware of the disease, especially in cases in which ophthalmic manifestation appear at the onset.

Stem Cells in the Path of Light, from Corneal to Retinal Reconstruction.

The future of eye reconstruction invariably includes stem cells transplantation. Corneal limbus, corneal stroma, trabeculum, retinal cells, optic nerve, and all structures that are irreversibly damaged and have no means to be repaired or replaced, through conventional treatment or surgery, represent targets for stem cell reconstruction. This review tries to answer the question if there is any clinical validation for stem therapies, so far, starting from the cornea and, on the path of light, arriving to the retina. The investigation covers the last 10 years of publications. From 2385 published sources, we found 56 clinical studies matching inclusion criteria, 39 involving cornea, and 17 involving retina. So far, corneal epithelial reconstruction seems well validated clinically. Enough clinical data are collected to allow some form of standardization for the stem cell transplant procedures. Cultivated limbal epithelial stem cells (CLET), simple limbal epithelial transplant (SLET), and oral mucosa transplantation are implemented worldwide. In comparison, far less patients are investigated in retinal stem reconstructions, with lower anatomical and clinical success, so far. Intravitreal, subretinal, and suprachoroidal approach for retinal stem therapies face specific challenges.

Perspectives of Molecularly Imprinted Polymer-Based Drug Delivery Systems in Ocular Therapy.

Although the human eye is an easily accessible sensory organ, it remains a challenge for drug administration due to the presence of several anatomical and physiological barriers which limit the access of drugs to its internal structures. Molecular imprinting technology may be considered the avant-garde approach in advanced drug delivery applications and, in particular, in ocular therapy. In fact, molecularly imprinted polymers hold the promise to compensate for the current shortcomings of the available arsenal of drug delivery systems intended for ocular therapy. The present manuscript aims to review the recent advances, the current challenges and most importantly to raise awareness on the underexplored potential and future perspectives of molecularly imprinted polymer-based drug delivery systems intended for the treatment of eye diseases.

Clinical Outcomes From Cultivated Allogenic Stem Cells vs. Oral Mucosa Epithelial Transplants in Total Bilateral Stem Cells Deficiency.

Total bilateral limbal stem cell deficiency results from various pathologies, from burns (either chemical or physical) to Sjogren Syndrome, aniridia or ocular cicatricial pemphigoid. After the loss of stem cells, normal corneal epithelium is replaced by a more opaque and vascularized conjunctival epithelium, causing loss of vision. After 1997, cultivation techniques for limbal stem cells became possible. In parallel, cultivation techniques for oral mucosa epithelial cells were also available. The aim of our review was to summarize the clinical outcomes following allogenic cultured limbal stem cell transplant (allogenic CLET), and on the other hand, oral mucosa derived epithelium transplant (cultivated oral mucosa epithelial transplant-COMET or cultivated autologous oral mucosal epithelial cell sheet-CAOMECS), in the case of total bilateral limbal stem cell loss. Thirty studies matching the inclusion criteria were found. The clinical improvement in both methods was reported similar, with percentages higher than 50% of the treated cases. However, the comparison between studies was difficult to achieve due to the lack of a universal and objective grading tool for assessing post-operative results. The definition of clinical improvement was problematic, because success was defined differently, depending on the study. Moreover, some of the studies followed both autologous and allogenic CLET, but described the results together, for both procedures, and therefore it was impossible to analyze them separately. COMET presented some advantages compared to CLET. By using autologous cells, there was no risk of immune activation and no immunosuppression was needed. COMET, however, might be associated with increased risk of persistent epithelial defects and graft failure, compared with allogenic CLET.

Orbital metastatic neuroblastoma presenting as posttraumatic exophthalmos.

A 2-year-old female patient with a recent history of head trauma was admitted to the Ophthalmology Clinic with left exophthalmos. A differential diagnosis between traumatic and tumoral etiology was made. The orbitocranial MRI and fine needle ganglion biopsy settled the malignant etiology of the exophthalmia. Further investigations at the Pediatric Oncology Clinic decided on the diagnosis of orbital metastatic neuroblastoma. This case report presented an unusual association: orbital metastatic neuroblastoma becoming clinically positive soon after a head trauma.

Is there a place for A-scan mode in modern eye ultrasonography?

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Medicinal Plants and Natural Products Used in Cataract Management.

Cataract is the leading reason of blindness worldwide and is defined by the presence of any lens opacities or loss of transparency. The most common symptoms of cataract are impaired vision, decreased contrast sensitivity, color disturbance, and glare. Oxidative stress is among the main mechanisms involved in the development of age-related cataract. Surgery through phacoemulsification and intraocular lens implantation is the most effective method for cataract treatment, however, there are chances of serious complications and irreversible loss of vision associated with the surgery. Natural compounds consisting of antioxidant or anti-inflammatory secondary metabolites can serve as potential leads for anticataract agents. In this review, we tried to document medicinal plants and plant-based natural products used for cataract treatment worldwide, which are gathered from available ethnopharmacological/ethnobotanical data. We have extensively explored a number of recognized databases like Scifinder, PubMed, Science Direct, Google Scholar, and Scopus by using keywords and phrases such as "cataract", "blindness", "traditional medicine", "ethnopharmacology", "ethnobotany", "herbs", "medicinal plants", or other relevant terms, and summarized the plants/phytoconstituents that are evaluated in different models of cataract and also tabulated 44 plants that are traditionally used in cataract in various folklore medical practices. Moreover, we also categorized the plants according to scientific studies carried out in different cataract models with their mechanisms of action.

[Dry eye--etiopathogenic and histopathologic correlations]. / Ochiul uscat--corelatii etiopatogenetice si histopatologice.

AIMS: To assess the role of the common inflammatory mechanism in the pathogenesis of the dry eye syndrome. METHODS: 64 patients with eye surface symptoms were studied using a diagnostic algorithm: questionnaire (eye symptoms were graded and a symptomatology SCORE was calculated), objective eye examination (including Schirmer's test and the tear film breakup time-BUT). Histopathological examination of 14 conjunctival bioptic fragments was performed. RESULTS: 59.37% of the patients had a positive Shirmer's test, while only 23% tested positively for the BUT. No statistically significant correlation was established between Schirmer's test and the BUT or the symptomatology SCORE. There was a significant correlation between BUT and the symptomatology SCORE (p<0.05) and between BUT and the duration of the disease (p<0.01). The histopathological examination of the dry eye conjunctival samples evidenced the following alterations: loss of calyciforme cells, squamous metaplasia of the epithelium, subepithelial inflammation. CONCLUSIONS: The histological analysis confirms the implication of inflammation in the pathogenesis of the disease. The time of onset of the inflammation cannot be established, it may be initial or it may occur with the quantitative decrease of tears or with eye surface alterations.

Epidemiology of ocular emergencies in Cluj ophthalmology clinic.

Objective. This study focused on the epidemiology of ocular diseases in the Eye Emergency Room. Methods. A cross-section retrospective study was performed in the Ophthalmology Clinic in Cluj-Napoca and included 11786 patients who presented to the Eye Emergency Room throughout the whole year, from January to December. Results. Every month, between 782 to 1189 patients with an average age of 39.54 years (±21.14) presented to the Eye Emergency Room. 250 were infants, under 1 year old. Six disease categories were followed: inflammation, trauma, vascular, tumor, glaucoma, and retinal-vitreal. Conjunctivitis and corneal foreign bodies accounted for almost half of the cases. Most of the conjunctival cultures revealed negative results. Conclusions. Consistent with the large number of patients included in this study, we considered the epidemiological data representative for our region. Male gender and youth represented the main risk factor for eye injury, while children remained the main group with conjunctivitis.

Cultivation and characterization of limbal epithelial stem cells in rabbits.

PURPOSE: In the last decades, strong evidence emerged regarding the presence of stem cells located at the corneal limbus. Our objective was to find a way to isolate and cultivate rabbit corneal stem cells in vitro, into an epithelial tissue. MATERIALS AND METHODS: Two in vitro systems were developed to culture rabbit corneal stem cells: (1) limbal biopsies used as explants and cultivated on fresh denuded amniotic membrane and (2) a monolayer culture obtained by enzymatic treatment of the corneal biopsies. Genetic characterization (PCR) was performed. Specific triggers were used to induce differentiation of corneal stem cells. RESULTS: At four weeks, 16 explant samples out of 18 cultures showed good expansion, ranging from 1 cm to 2 cm. Genetic characterization showed similar expression of genetic stem markers for corneal stem cells and placental stem cells, previously characterized (stem cell factor, Oct3/4, Vimentin, Nestin and Neurofilament). Corneal stem cells showed high Rhodamine efflux and were effective progenitors for neuronal, myocardial, osteogenic and endothelial lineage. CONCLUSIONS: In one month, it was possible to grow enough epithelial tissue with preserved proliferative state to allow transplantation on the cornea.