Background and Objectives: Herpes simplex keratitis (HSK) is the leading infectious cause of corneal damage and associated loss of visual acuity. Because of its frequent recurrence, it represents a major health problem; thus, timely and accurate diagnosis is the key to successful treatment. To enable this, we aimed to determine HSK patients’ demographic and clinical features. Materials and Methods: This prospective study included 55 patients diagnosed with HSK between March 2019 and August 2022 at the Department of Ophthalmology, Clinical Hospital Rijeka. Results: We found that HSK is most prevalent in the elderly, with 72.73% of patients older than 60. The most common HSK types were dendritic (HSK-D; 43.64%) and stromal with epithelial ulceration (HSK-SEU 23.64%). HSK recurrences occurred in 65.45% of patients, with most having two to five recurrences (55.56%). Visual acuity at presentation (65.5%) and after treatment (50.9%) was mostly in the 20/50 range. The longest period until the disease symptoms were resolved was in the group with stromal HSK without epithelial ulceration (HSK-SnEU), for which symptoms lasted more than 11 weeks in 87.5% of patients. The overall incidence of HSK-related complications was high (85.45%), with 76.4% of patients having corneal scarring. The average time from symptom to treatment was 15.78 days. Interestingly, we observed a strong seasonality in the incidence of HSK, which was most prevalent in the colder months, with 63.6% of cases occurring between October and March. Conclusions: To the best of our knowledge, this is the first prospective study in Croatia, and one of the few in Europe, to describe the demographic and clinical features of HSK patients. We found that HSK is most common in the elderly population, with its dendritic form as a clinical presentation. We have shown that HSK is prone to recurrence and secondary complications, with a worryingly long time between symptom and treatment, indicating the need for diagnostic testing in routine practice.

In relation to the eye, the body can absorb substances from the ocular surface fluid (OSF) in a few ways: directly through the conjunctival sac, through the nasal mucosa as the fluid drains into the nose, or through ingestion. Regardless of the absorption method, fluid from the conjunctival sac should be used as a toxicological matrix, even though only small quantities are needed. Contemporary analytical techniques make it a suitable matrix for toxicological research. Analyzing small quantities of the matrix and nano-quantities of the analyte requires high-cost, sophisticated tools, which is particularly relevant in the high-throughput environment of new drug or cosmetics testing. Environmental toxicology also presents a challenge, as many pollutants can enter the system using the same ocular surface route. A review of the existing literature was conducted to assess potential applications in clinical and forensic toxicology related to the absorption of toxicants from the ocular surface. The selection of the studies used in this review aimed to identify new, more efficient, and cost-effective analytical technology and diagnostic methods.

Background and Objectives: Pseudoexfoliative glaucoma (PEXG) is a secondary glaucoma caused by the deposition of abnormal flaky protein-like material inside the eye, leading to blockage of the drainage system, increased intraocular pressure (IOP), and optic nerve damage. This study aimed to evaluate the effects of latanoprost and timolol–dorzolamide therapy on the concentrations of interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-12p70, and tumor necrosis factor-alpha (TNF-α) in the aqueous humor and serum samples of patients with PEXG. Materials and Methods: This prospective observational study included 60 patients allocated to three age-matched groups (n = 20 per group). Group 1 received latanoprost therapy, Group 2 received timolol–dorzolamide therapy, and Group 3 comprised patients with cataracts without PEXG who were not receiving antiglaucoma medication (control group). All participants underwent a comprehensive ophthalmological examination, including visual acuity assessment, specular microscopy, IOP measurement, and intraocular lens (IOL) measurement. Peripheral venous blood was taken from each patient before the surgical procedure and aqueous humor samples were collected during cataract surgery. Concentrations of IL-1β, IL-6, IL-8, IL-10, IL-12p70, and TNF-α were determined using a Cytometric Bead Array and flow cytometry. Results: No significant differences were observed in the aqueous humor and serum concentrations of IL-6 and IL-8 between the treatment groups, while IL-1β, IL-10, IL-12p70, and TNF-α did not reach detection. A significant positive correlation was found between IOL and aqueous humor IL-6 concentration in group 1 and between IL-6 and IL-8 serum concentration and IOP in controls. Conclusions: Latanoprost and timolol–dorzolamide therapy were not associated with significant differences in aqueous humor or serum IL-6 and IL-8 concentrations in patients with PEXG. IL-1β, IL-10, IL-12p70, and TNF-α were not detectable in the analyzed samples. These findings support the presence of low-grade inflammation in patients with PEXG that does not differ according to the therapy administered. Corneal endothelial alterations are disease-related rather than treatment-induced.