Short-term effect of non-preserved cationic oil in-water ophthalmic emulsion on tear meniscus parameters of healthy individuals in a prospective, controlled pilot study

Background: This study investigated the effect of instilling a single drop of non-preserved cationic oil-in-water ophthalmic emulsion (Cationorm®) on the lower (LTM) and upper tear meniscus (UTM) parameters of normal eyes. Methods: In this prospective, single-center, non-randomized, controlled pilot study, optical coherence tomography was used to estimate the UTM and LTM height, depth, and cross-sectional area in participants without a history of dry eye disease. In the right eye (study eye), we instilled one drop of Cationorm® in the lower conjunctival sac. Scans of the tear menisci were acquired at baseline, before the instillation, and at 5, 15, and 30 min thereafter. Control scans of the left eye (control eye) were obtained at the same timepoints. The tear meniscus parameters of the study eye were compared with the control eye at each timepoint. Results: Twenty subjects (11 male and 9 female; mean ± standard deviation of age: 37.8 ± 10.9 years) were included in the study. Compared to the control eye, instillation of a single drop of Cationorm® resulted in significantly higher LTM parameter values and a higher UTM cross-sectional area up to 30 min after instillation (all P < 0.05). The UTM height and depth were significantly greater in the study eye than in the control eye up to 5 min (P < 0.001 and 0.007, respectively) and 15-min (P = 0.045, and 0.002, respectively) after Cationorm® instillation. In the study eye, Cationorm® resulted in a significant increase in LTM parameter values up to 30 min post-instillation (all P < 0.001). The UTM height was significantly greater up to 15 min post-instillation than at baseline. The UTM depth and area increased significantly from baseline to 5 min after instillation (P = 0.043, and 0.002, respectively). Conclusions: Cationorm® seems to have a prolonged residence time on the ocular surface of healthy subjects as indicated by LTM parameters and to a lesser extent by UTM parameters

Expression and Localization of Glycosaminoglycans/Proteoglycan in Pterygium: An Immunohistochemical Study

Pterygium is a triangle-shaped fibrovascular hyperplasia of the bulbar conjunctiva on the cornea. The purpose of this study was to analyze Proteoglycans (PGs) by Immunohistochemistry (IHC) in pterygium tissues and to compare the results with normal conjunctiva. Twenty-four patients (14 males) undergoing primary pterygium excision and 17 healthy individuals (10 males), undergoing extracapsular cataract surgery, were included. Pterygium tissues and normal conjunctiva tissues were surgically removed. The tissue sections were fixed in 2% paraformaldehyde and incubated with monoclonal antibodies against PGs anti-mouse IgG. Immunohistochemical study showed stronger expression of keratan sulfate in the stroma of the pterygium compared to normal conjunctiva. An increased expression of heparan sulfate was observed in the epithelial layer and around the pterygium vessels. On the other hand, dermatan sulfate showed an increased expression and localization not only in the sub-epithelial area of the pterygium and normal conjunctiva, yet throughout the stroma of the pterygium. The differences in the expression and localization of the studied extracellular matrix proteoglycans in the pterygium tissue compared to normal conjunctiva may explain the tissue hyperplasia, structure, and the functional properties in pterygium

Bacteriology and Antimicrobial Susceptibility Patterns of Childhood Acute Bacterial Conjunctivitis in Western Greece

Acute bacterial conjunctivitis is a common, highly contagious infection in children and is usually treated empirically with broad spectrum topical antibiotics. In the current study we investigated bacteriology and antibiotic susceptibility patterns in childhood acute bacterial conjunctivitis in Western Greece. We conducted a retrospective analysis of presumed acute bacterial conjunctivitis cases in ''Karamandaneio'' Pediatric General Hospital of Patras, Western Greece, between February 1, 2013 and January 31, 2018. Specimens from the lower conjunctiva fornix were isolated from 191 cases and outcomes were analyzed to identify the pathogenic bacteria of acute bacterial conjunctivitis and their corresponding antibiotic susceptibility patterns. Patients were divided into 3 groups; Group A included neonates under 28 days of life, Group B children from 1 month to 2 years and Group C from 2 years to 14 years. Results revealed that Staphylococcus spp., Haemophilus spp. and Streptococcus spp. were the most prevalent pathogens. No significant differences in isolated pathogens were found between the age groups. Antibiotic resistance rates were higher against ampicillin, ceftriaxone, ceftazidime and sulfamethoxazole. Resistance rates to Ciprofloxacin were low while none of the evaluated isolates were resistant to vancomycin. We concluded that predominant pathogens of childhood acute bacterial conjunctivitis in Western Greece were Staphylococcus spp., Haemophilus spp. and Streptococcus spp. Continuous surveillance, focused in distinct geographic areas, is encouraged to prepare more precise protocols of empirical treatment. Epub: October 1, 2019

Preservative-free versus preserved latanoprost eye drops for reducing intraocular pressure: a non-inferiority phase III randomized, multi-center, single-blind, parallel-group controlled trial

Background: The aim of this study was to test the non-inferiority of preservative-free (PF) latanoprost 50 μg/mL multi-dose ophthalmic solution versus the marketed benzalkonium chloride (BAK)-preserved latanoprost 50 μg/mL ophthalmic solution in patients with open-angle glaucoma and patients with ocular hypertension. Methods: This was a prospective, national, randomized, multi-center, observer-blind, parallel-group controlled clinical trial. Patients were randomized to receive either PF or BAK-preserved latanoprost once daily for 12 weeks. The primary endpoint was the change in intraocular pressure (IOP) at 8:00 AM in the affected eye between the end of the treatment (week 12) and the baseline (week 0). Secondary measurements were taken at weeks 2 and 6, with IOP being recorded at 8:00 AM, 12:00 PM, and 4:00 PM. Results: A total of 158 patients were included in the per protocol (PP) population (77 in the PF latanoprost treatment arm and 81 patients in the BAK-preserved latanoprost treatment arm). PF latanoprost was non-inferior to BAK-preserved latanoprost in reducing IOP at 8:00 AM in the study eye from the baseline (week 0) to the end of the treatment (week 12). The point estimate of the between-treatment difference was 0.1 mmHg (95% confidence interval: -0.646, 0.847). Mean between-group differences in IOP reduction from the baseline to each of the secondary measurements were also similar between the two treatment arms. The two treatments were well tolerated and had comparable adverse event profiles. Conclusions: PF latanoprost was non-inferior to BAK-preserved latanoprost in reducing IOP in patients with open-angle glaucoma or ocular hypertension. Both treatments were well tolerated

Non-inferiority evaluation of preservative-free latanoprost/timolol eye drops solution versus preserved latanoprost/timolol eye drops in patients with high intraocular pressure and open-angle glaucoma

Background: This study aimed to evaluate the non-inferiority and safety of a newly developed preservative-free (PF) multi-dose latanoprost/timolol ophthalmic solution, compared with the benzalkonium chloride (BAK)-preserved fixed combination, in patients with open-angle glaucoma and ocular hypertension.Methods: A Phase III randomized multi-center observer-blind parallel-group clinical trial was conducted. A total of 210 adult patients (aged over 18 years) were randomly treated with the PF- or the BAK-preserved latanoprost/timolol solution once daily in the affected eye(s) for 12 weeks. Follow-up visits were scheduled at weeks 2, 6, and 12; intraocular pressure (IOP) was recorded at 8:00 AM, 12:00 PM, and 4:00 PM. The primary efficacy endpoint to prove non-inferiority was the IOP change at 8:00 AM (± 1 hour) from the baseline to the end of treatment (week 12) in the studied eye. Safety parameters were also assessed.Results: In total, 196 patients completed the study. The pressure-lowering effect of the PF eye drops was comparable to that of the preserved formulation at all time points. Latanoprost/timolol PF formulation was non-inferior to the BAK-preserved solution as shown by the change in IOP from day 0 to week 12. The point estimate of the inter-treatment difference was 0.624 mmHg (95% CI: -0.094, 1.341). Both treatments were well-tolerated during the study, and they had similar adverse event profiles.Conclusions: PF-latanoprost/timolol combination was found to be non-inferior to the BAK-preserved formulation based on the efficacy at all times, with similar local tolerance

Nanotechnology-based formulations to amplify intraocular bioavailability

Conventional drug delivery formulations, such as eye drops and ointments, are mainly administered by topical instillation. The topical delivery of ophthalmic drugs is a challenging endeavor despite the eye is easily accessible. Unique and complex barriers, serving as protection against extrinsic harmful factors, hamper therapeutic intraocular drug concentrations. Bioavailability for deeper ocular tissues of the anterior segment of the eye is exceptionally low. As the bioavailability of the active substance is the major hurdle to overcome, dosing is increased, so the side effects do. Both provoke patient poor compliance, confining the desired therapeutic outcome. The incidence and severity of adverse reactions amplify evenly in the case of chronic treatments. Current research focuses on the development of innovative delivery strategies to address low ocular bioavailability and provide safe and convenient dosing schemes. The main objective of this review is to explore and present the latest developments in ocular drug delivery formulations for the treatment of the pathology of the anterior segment of the eye. Nanotechnology-based formulations, that is, organic nanoparticles (liposomes, niosomes/discosomes, dendrimers, nanoemulsions, nanosuspensions, nanoparticles/nanospheres) and inorganic nanoparticles, nanoparticle-laden therapeutic contact lenses, in situ gelling systems, and ocular inserts, are summarized and presented accordingly

Late-Onset Bilateral Choroidal Metastases from Clear Cell Renal Cell Carcinoma

Aim. To present a case of clear cell renal cell carcinoma with late-onset bilateral choroidal metastases. Case Report. A 57-year-old male patient in the Oncology Clinic complained of reduced vision in the right eye (OD) for 7 days. The patient, who was under immunotherapy with nivolumab, had been diagnosed with clear cell renal cell carcinoma in the left kidney 15 years ago that recurred in the right kidney before 2 years. Metastases in the brain, lungs, and bones had also been diagnosed. On ophthalmological examination, the visual acuity was 20/50 OD and 20/20 in the left eye (OS). Dilated fundus examination in OD revealed a single raised oval-shaped yellowish choroidal nodule infratemporally with macular involvement. A similar lesion, sparing the macula, was observed in OS. Fundus autofluorescence revealed diffuse punctate hyperautofluorescence on the lesions. Serous macular detachment was also observed in OD. A standardized A-scan ultrasound demonstrated an irregular structure of the lesions with moderate to high internal reflectivity. Based on the history and clinical and echographic characteristics, the diagnosis of bilateral choroidal metastases from renal cell carcinoma was set. Conclusion. Choroidal metastases from the primary renal tumor are extremely rare. The time interval between primary malignancy and choroidal metastasis is reported to be 12-96 months. Bilateral choroidal metastases have been described in 9 cases. We describe a rare case where bilateral choroidal metastases were diagnosed 15 years after the initial diagnosis of clear cell renal cell carcinoma

A Finite Element-Based Characteristic Mode Analysis

International audienceA novel Green's function-free characteristic modes formulation is introduced in this work. The desired impedance or admittance matrix is obtained utilizing and appropriately modifying the versatile finite element method. For this purpose, the generalized eigenvalue problem of the electric or magnetic field vector wave equation is formulated. In the case of the electric field wave equation, using the Schur complement, the system is reformulated and expressed only in terms of the tangential electric field over the radiating apertures, retaining the equivalent magnetic currents. Similarly, in the case of the magnetic field wave equation, the electric current density on radiating metallic surfaces is isolated using the Schur complement. In both cases, the obtained matrix is split into its real and imaginary part to yield the characteristic modes eigenvalue problem. Key advantage of the proposed formulation is that it does not require the evaluation of Green's function, thereby the study of any arbitrarily shaped, multilayered geometry loaded with anisotropic and inhomogeneous materials is feasible. To prove the validity of the proposed methodology various classical structures, with both homogeneous, and inhomogeneous and anisotropic materials, published in the bibliography are studied. Both the eigenvalues and eigenvectors compared with the published results show good agreement

Antioxidant Defense and Pseudoexfoliation Syndrome: An Updated Review

Oxidative stress (OS) affects the anterior ocular tissues, rendering them susceptible to several eye diseases. On the other hand, protection of the eye from harmful factors is achieved by unique defense mechanisms, including enzymatic and non-enzymatic antioxidants. The imbalance between oxidants and antioxidants could be the cause of pseudoexfoliation syndrome (PEXS), a condition of defective extracellular matrix (ECM) remodeling. A systematic English-language literature review was conducted from May 2022 to June 2022. The main antioxidant enzymes protecting the eye from reactive oxygen species (ROS) are superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), which catalyze the reduction of specific types of ROS. Similarly, non-enzymatic antioxidants such as vitamins A, E and C, carotenoids and glutathione (GSH) are involved in removing ROS from the cells. PEXS is a genetic disease, however, environmental and dietary factors also influence its development. Additionally, many OS products disrupting the ECM remodeling process and modifying the antioxidative defense status could lead to PEXS. This review discusses the antioxidative defense of the eye in association with PEXS, and the intricate link between OS and PEXS. Understanding the pathways of PEXS evolution, and developing new methods to reduce OS, are crucial to control and treat this disease. However, further studies are required to elucidate the molecular pathogenesis of PEXS