Modern Technologies in Diagnosis of Fungal Keratitis (Review)

Abstract

Traumas and infectious diseases of the eye play a leading role in the development of corneal blindness responsible for 1.5–2 million cases of vision loss per year. To date, the issue of reducing the incidence of fungal keratitis is acute and needs to be solved worldwide. Trauma as a risk factor for corneal fungal disease is thought to be prevalent in developing countries due to agricultural involvement, while in developed countries the onset of the disease is predisposed by medical advances such as contact vision correction and modern ophthalmic surgery. Thorough analysis of the pathogenesis gives the possibility to describe the action of fungal enzymes, biofilm formation, and the resistance mechanism, which on the one hand explains the aggressive course of the disease and difficulties in its diagnosis, and on the other hand, it encourages searching for new methods of diagnosis and treatment. The non-specific clinical picture of fungal keratitis, the variety and availability of antibiotics nowadays become an obstacle for rapid detection of this pathology. Low public awareness and late visit to an ophthalmologist are also a barrier to successful combating the increasing incidence of fungal keratitis. Belated diagnosis, increasing resistance of fungi to antibiotics, and lack of registered antifungal ophthalmic drugs justify poor treatment efficacy resulting in decreased visual acuity or vision loss . Existing diagnostic methods need systematization and detailed comparison, identifying the advantages and disadvantages of each. This review considers causative agents and their influence on pathogenesis of the disease, describes difficulties of fungal keratitis diagnosis and possible ways of overcoming these problems using new developments, and also outlines further prospects of research in this direction.

A Comprehensive Review of Microbial Biofilms on Contact Lenses: Challenges and Solutions

“…Photophobia and blepharospasm can hinder the process. 36 Anterior segment optical coherence tomography (OCT) enables the detection of corneal alterations indicative of the mycotic process. According to the OCT results, the cornea in the infiltrate region has thickened.…”

Sustained Release of Voriconazole Using 3D-Crosslinked Hydrogel Rings and Rods for Use in Corneal Drug Delivery

“…However, surgical intervention is required in a considerable number of cases (around 40% [3]). Three factors hamper the success of early therapies based on eye drops: (i) the fact that a portion of an eye drop is spilled immediately after instillation due to blinking (spill rate can be >90%); (ii) clearance of the drug due to flow of the tear film toward the nasolacrimal duct; and (iii) the fact that the cornea poses a considerable barrier to diffusion of the drug toward the ulcer, especially when the ulcer has developed in deep-lying parts of the stroma [6][7][8]. The three factors suppress the so-called bioavailability of antifungal drugs from eye drops and, therefore, influence the efficacy of early treatment therapies for fungal keratitis.…”