Purpose: To evaluate the microbiota of culture negative Corneal Impression Membrane (CIM) microbial keratitis samples with the use of shotgun metagenomics analysis. Methods: DNA of microbial keratitis samples were collected with CIM and extracted using the MasterPure™ Complete DNA and RNA Purification Kit (Epicentre). DNA was fragmented by sonication into fragments of 300 to 400 base pairs (bp) using Bioruptor® (Diagenode, Belgium) and then used as a template for library preparation. DNA libraries were sequenced on Illumina® HiSeq2500. The resulting reads were quality controlled, trimmed and mapped against the human reference genome. The unmapped reads were taxonomically classified using the Kraken software. Results: 18 microbial keratitis samples were included in the study. Brevundimonas diminuta was found in 5 samples while 6 samples showed the presence of viral infections. Cutibacterium acnes, Staphylococcus aureus, Moraxella lacunata and Pseudomonas alcaligenes were also identified as the presumed putative cause of the infection in 7 samples. Conclusions: Shotgun sequencing can be used as a diagnostic tool in microbial keratitis samples. This diagnostic method expands the available tests to diagnose eye infections and could be clinically significant in culture negative samples.

Purpose: The purpose of this study was to check the efficacy and safety of a novel tear substitute containing hyaluronic acid and low-dose hydrocortisone in the treatment of moderate dry eye disease. Methods: In this prospective randomized study, 38 patients with moderate dry eye disease were divided into two treatment groups: Group 1 received one drop of 0.2% sodium hyaluronate and 0.001% hydrocortisone four times daily for 3 months, while Group 2 received 0.15% sodium hyaluronate and 3% trehalose at the same dosage. OSDI and SANDE questionnaires, Non-Invasive Break-Up time (NIBUT), Tear Meniscus Height (TMH), meibography, Lipid Layer Thickness (LLT), Tear Break-Up Time (TBUT), Corneal Staining Score (CFS), and Intraocular Pressure (IOP) were evaluated at baseline and after 1, 2, and 3 months of treatment. Results: During the treatment period, Group 1 showed statistically significant improvement in OSDI score (p = 0.002), SANDE score (p = 0.01), NIBUT (p < 0.0001), LLT (p < 0.0001), TBUT (p = 0.01), and CFS (p = 0.02). In Group 2, significant improvement was observed only in the TBUT score (p < 0.05). Comparison of the two groups showed that NIBUT and LLT were significantly different at the end of treatment (p = 0.001 for both comparisons), with more favorable results for sodium hyaluronate and hydrocortisone than for sodium hyaluronate and trehalose. No significant variations in intraocular pressure were observed in either group during the treatment period (p > 0.05). Conclusions: The study confirms that a 3-months treatment with hyaluronic acid 0.2% in combination with low-dose hydrocortisone 0.001% improves the signs and symptoms of moderate DED and that a low-dosage 0.001% hydrocortisone can be helpful in preventing the progression to chronic stages of DED.

Pseudopterygium is a non-progressive conjunctival adhesion to the peripheral cornea secondary to a corneal-limbus damage. According to the literature, the main etiology is a previous eye trauma. Nevertheless, this could be biased by the existence of other underdiagnosed causes of pseudopterygium, some of which may have severe consequences for the integrity of the eye and patient’s life. This comprehensive literature review was performed based on a search on the PubMed and Google Scholar databases of relevant pseudopterygium published papers according to our current knowledge and seeks to gather the existing evidence about its diverse etiologies and clinical features, as well as to propose a diagnostic algorithm to simplify its correct approach.

Purpose: To report the effectiveness of the surgical procedure of the tarsoconjunctival flap (FTC) in patients with severe ocular surface impairment refractory to previous conventional treatments. Methods: A retrospective, noncomparative, consecutive case series. Results: Pillar tarsoconjunctival flap (PTCF) was performed in eight eyes of eight patients. Three patients had neurotrophic corneal ulcer (NCU), three had exposure keratopathy and two had corneal melting. Seven of them had satisfactory postoperative results, showing total corneal re-epithelialization that lasted throughout the postoperative follow-up (mean 10.33 ± 2.65 months [SD], range 6 to 12 months). Mean time for the re-epithelization was 11.28 ± 8.97 days [SD] (range 4 to 30 days). Conclusion: This study suggest PTCF is a valid alternative to tarsorrhaphy in cases of persistent epithelial defect (PED) or NCU resistant to conventional treatments. Notwithstanding, prospective comparative trials comparing PTFC with conventional and/or novel therapies in PED or NCU are needed to corroborate these findings.