Challenges in the clinical measurement of ocular surface disease in glaucoma patients

Ocular surface disease (OSD) is common among glaucoma patients. Clinical assessment of OSD can be challenging. This review focuses on some of the limitations relating to both subjective and objective measures of OSD, including dry eye. A survey of the literature was conducted to identify the caveats associated with different methods of assessing OSD. The effect of preservatives on the ocular surface, with respect to glaucoma patients in particular, was also reviewed. Objective methods for assessing ocular surface health and disease include the Schirmer test, tear break-up time, fluorescein turnover, corneal and conjunctival staining, tear osmolarity, and vital dyes. These measures all have limitations in terms of their ability to grade the severity of OSD. Previous studies using the OSD Index showed a mild-to-moderate correlation to dry eye disease severity. Other scoring systems for dry eye have shown a relationship to patient symptom scores or quality of life. Due to the challenges clinicians face concerning both subjective and objective ocular surface health assessments, discerning clinical improvement in ocular surface disease can be a challenge. Further research is needed in order to optimize existing clinical methods and/or identify alternative techniques for assessing OSD in the glaucoma population

Cross-validating precipitation datasets in the Indus River basin

Abstract. Large uncertainty remains about the amount of precipitation falling in the Indus River basin, particularly in the more mountainous northern part. While rain gauge measurements are often considered as a reference, they provide information for specific, often sparse, locations (point observations) and are subject to underestimation, particularly in mountain areas. Satellite observations and reanalysis data can improve our knowledge but validating their results is often difficult. In this study, we offer a cross-validation of 20 gridded datasets based on rain gauge, satellite, and reanalysis data, including the most recent and less studied APHRODITE-2, MERRA2, and ERA5. This original approach to cross-validation alternatively uses each dataset as a reference and interprets the result according to their dependency on the reference. Most interestingly, we found that reanalyses represent the daily variability of precipitation as well as any observational datasets, particularly in winter. Therefore, we suggest that reanalyses offer better estimates than non-corrected rain-gauge-based datasets where underestimation is problematic. Specifically, ERA5 is the reanalysis that offers estimates of precipitation closest to observations, in terms of amounts, seasonality, and variability, from daily to multi-annual scale. By contrast, satellite observations bring limited improvement at the basin scale. For the rain-gauge-based datasets, APHRODITE has the finest temporal representation of the precipitation variability, yet it importantly underestimates the actual amount. GPCC products are the only datasets that include a correction factor of the rain gauge measurements, but this factor likely remains too small. These findings highlight the need for a systematic characterisation of the underestimation of rain gauge measurements. European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 648609

Research on the Stability of a Rabbit Dry Eye Model Induced by Topical Application of the Preservative Benzalkonium Chloride

Dry eye is a common disease worldwide, and animal models are critical for the study of it. At present, there is no research about the stability of the extant animal models, which may have negative implications for previous dry eye studies. In this study, we observed the stability of a rabbit dry eye model induced by the topical benzalkonium chloride (BAC) and determined the valid time of this model.). Decreased levels of mucin-5 subtype AC (MUC5AC), along with histopathological and ultrastructural disorders of the cornea and conjunctiva could be observed in Group BAC-W4 and particularly in Group BAC-W5 until day 21.A stable rabbit dry eye model was induced by topical 0.1% BAC for 5 weeks, and after BAC removal, the signs of dry eye were sustained for 2 weeks (for the mixed type of dry eye) or for at least 3 weeks (for mucin-deficient dry eye)

Efficacy and Safety of 0.1% Cyclosporine a Cationic Emulsion in the Treatment of Severe Dry Eye Disease: A Multicenter Randomized Trial:

PurposeThe SANSIKA study was conducted to assess the treatment effect of 0.1% cyclosporine A cationic emulsion (CsA CE) eye drops on signs and symptoms of patients with severe dry eye disease (DED)..