Grooved and nongrooved clear corneal incisions in phacoemulsification: permeability study.

PURPOSE: To detect the inflow of trypan blue through grooved and nongrooved sutureless self-sealing clear corneal incisions at the end of phacoemulsification as compared to a control group. METHODS: A prospective randomized masked trial considered 52 eyes randomized into 3 groups in which phacoemulsification was performed: group A, nongrooved incisions; group B, grooved incisions; and group C, controls. By the end of each surgery, trypan blue was instilled on the ocular surface in groups A and B and rinsed out after 2 minutes. A sample of the anterior chamber content was collected and analyzed by high-performance liquid chromatography to identify and quantify the trypan blue concentration. The presence of trypan blue was expressed as a specific single peak graphic image. The mean areas of these peaks were used to assess the groups using a nonparametric Mann-Whitney test. RESULTS: There was a statistically significant difference between the nongrooved incisions group and the control group (p = 0.0448). No significant difference was observed between group B (grooved incision) and controls (p = 0.1800). CONCLUSIONS: Trypan blue was detected in the anterior chamber when nongrooved clear corneal incision was used. There was no trypan blue detection in the group with grooved clear corneal main incisions.

In vitro antimicrobial analysis of aqueous humor after topical application of moxifloxacin hydrochloride 0.5%.

PURPOSE: To evaluate the in vitro antimicrobial activity of aqueous humor in patients who had preoperative topical application of moxifloxacin hydrochloride 0.5%. SETTING: Department of Ophthalmology, Santa Casa de Misericórdia de São Paulo, Brazil. DESIGN: Comparative case series. METHODS: Twenty-nine eyes from 29 cataract surgery patients were included in this study. In the study group (n = 15 eyes), 3 topical applications of moxifloxacin hydrochloride 0.5% were administered preoperatively; in the control group (n = 14 eyes), no topical applications were administered. Aqueous humor samples were collected and stored in sterile microtubes at -80°C until analysis. Antimicrobial analysis was performed using standard strains with standard sterile filter paper disks. Inhibition halos were measured in millimeters, and both bactericidal and bacteriostatic effects were analyzed. RESULTS: Inhibition halos were observed on most of the study group plates except those with Streptococcus pneumoniae: Escherichia coli (13.93 mm ± 0.64 [SD]), Klebsiella pneumoniae (10.63 ± 0.61 mm), Staphylococcus aureus (7.47 ± 0.68 mm), and S epidermidis (4.20 ± 3.33 mm) The differences between the mean inhibition halo diameters were statistically significant (P < .0001) in all samples. No bactericidal effect was observed against any of the microorganisms studied. CONCLUSIONS: After topical application of moxifloxacin 0.5%, aqueous humor showed bacteriostatic effect against E coli, K pneumoniae, S aureus, and S epidermidis. No bactericidal effect was observed against any of the microorganisms evaluated. No antimicrobial effect against S pneumoniae was observed. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.