Are Prophylactic Systemic Antibiotics Required in Patients with Cataract Surgery at Local Anesthesia?

The reduced use of antimicrobial drugs has been recommended worldwide, according to the global action for antimicrobial resistance published in 2015 by the World Health Organization. In this study, we retrospectively reviewed the incidence of surgical site infection in consecutive patients with cataract surgeries at a single hospital in the 6-year process when prophylactic systemic antibiotics were reduced in a step-by-step manner. The entire study period from 2016 to 2022 was divided into five stages, based on the use of systemic antibiotics. In stage 1 with 649 cataract surgeries, an intravenous drip infusion of cefazolin 1 g was given at surgery, followed by oral cefdinir 100 mg in the evening on surgery day and three times for two postoperative days. In stage 2 with 541 cataract surgeries, oral cefdinir 100 mg was given in the late morning before surgery, in the evening, and three times (300 mg in total) for two postoperative days. In stage 3 with 103 cataract surgeries, oral levofloxacin 500 mg was given in the late morning before surgery and once in the morning for two postoperative days. In stage 4 with 545 cataract surgeries, oral levofloxacin 500 mg was given only in the late morning before surgery. In stage 5 with 311 cataract surgeries, no systemic antibiotics were given. As common procedures in all stages, moxifloxacin eye drops were given four times daily as topical antibiotics in the 3 days before surgery and about 2 weeks after surgery. At surgery, the ocular surface was frequently irrigated with saline-diluted povidone iodine at 0.5% working concentration. No postoperative infection was recorded in any stage. This study showed neither harm nor risk in reduced use and, consequently, no use of prophylactic systemic antibiotics in cataract surgery as far as local precautionary measures were secured.

Trehalose versus hyaluronan or cellulose in eyedrops for the treatment of dry eye.

PURPOSE: Trehalose eyedrops were found by a previous study to be safe and effective compared with saline in the treatment of moderate-to-severe dry eye syndrome. The present study was designed to compare the efficacy of trehalose eyedrops with that of the commercially available eyedrops containing hyaluronan or cellulose now used in the treatment of moderate-to-severe dry eye syndrome. METHODS: In a randomized, double-masked, 4-week crossover, controlled clinical trial, 36 patients with moderate-to-severe dry eye syndrome were divided into two groups: the hyaluronan (Hyalein)-comparison group (18 patients) and the hydroxyethylcellulose (Mytear)-comparison group (18 patients). Each group used either trehalose or one of the commercially available medications contained in a masked eyedrop container for the first 4 weeks, and then for the second 4 weeks, switched to either trehalose or the commercial eyedrop not used for the first 4 weeks. Symptoms and signs in both eyes were recorded at the baseline, at 4 weeks, and at 8 weeks. RESULTS: At 4 weeks after the treatment, fluorescein and rose bengal staining scores of the ocular surface as well as the tear film breakup time had improved significantly with trehalose eyedrops compared with the commercially available eyedrops containing either hyaluronan or hydroxyethylcellulose (P < 0.001, Wilcoxon signed ranks test). In addition, all the objective signs were significantly better in patients who finished with trehalose at the end of the 8-week trial compared with those who finished with either of the two commercially available drugs. A larger number of patients evaluated trehalose as a better treatment than the commercially available eyedrops. CONCLUSIONS: Trehalose solution was a better treatment for moderate-to-severe dry eye syndrome in comparison with two commercially available eyedrops containing hyaluronan or hydroxyethylcellulose.

A simple method for screening photoelectric dyes towards their use for retinal prostheses.

Photoelectric dyes absorb light and convert photon energy to electric potentials. To test whether these dyes could be used for retinal prostheses, a simple in vitro screening system was developed. Retinal neurons were cultured from the eyes of chick embryos at the 10-day embryonic stage, at which time no retinal photoreceptor cells have yet developed. Intracellular calcium elevation was observed with Fluo-4 in cultured retinal neurons before and after photoelectric dye was applied at varying concentrations to the culture medium. Five of 7 photoelectric dyes tested in this in vitro system induced intracellular calcium elevation in cultured chick retinal neurons. The intracellular calcium elevation generated by the 5 photoelectric dyes was blocked by extracellular calcium depletion in the case of all 5 dyes, and, except for one dye, by the presence of voltage-gated calcium channel blockers. The photoelectric dyes absorbed light under an inverted microscope and stimulated retinal neurons. This simple in vitro system allows the screening of photoelectric dyes which can be used for retinal prostheses.

Trehalose eye drops in the treatment of dry eye syndrome.

OBJECTIVE: Trehalose can protect human corneal epithelial cells in culture from death from desiccation. This study was designed to test the efficacy and safety of trehalose eyedrops in the treatment of moderate to severe dry eye syndrome. DESIGN: A randomized, double-masked, dose-ranging, fellow eye-controlled clinical trial. PARTICIPANTS: Thirty-four patients with moderate to severe dry eye syndrome. METHODS: The patients used either 100 or 200 mM trehalose dissolved in saline six times daily in one eye and control saline in the other eye for 4 weeks. MAIN OUTCOME MEASURES: Symptoms and signs in both eyes were recorded separately at baseline, 2 weeks, and 4 weeks. RESULTS: Fluorescein and rose bengal staining scores of the ocular surface improved at both 2 weeks and 4 weeks in the eyes with 100 and 200 mM trehalose, compared with eyes with control saline (P = 0.0030 to P < 0.0001, respectively, Mann-Whitney U test). Tear film breakup time became significantly longer at 2 weeks and 4 weeks with 100 mM trehalose (P = 0.0024 and P < 0.0001, respectively), but not with 200 mM trehalose. No adverse effect attributable to trehalose solution was noted. CONCLUSIONS: Trehalose solution was an effective and safe eyedrop for the treatment of moderate to severe dry eye syndrome in this group of patients.