Complication of an Ahmed glaucoma valve implant: tube exposure with methicillin-resistant Staphylococcus aureus infection.

Neovascular glaucoma is commonly treated surgically with implantation of glaucoma drainage devices. We report the case of a 57-year-old man who underwent an uneventful Ahmed glaucoma valve (AGV) placement for radiation-induced neovascular glaucoma but later developed early postoperative infection with tube exposure. The infection was identified 3 weeks postoperatively and antibiotic treatment was immediately initiated. However, the conjunctival melt progressed, and the AGV had to be removed. Culture of the device revealed methicillin-resistant Staphylococcus aureus (MRSA). There is a potential increased risk of postoperative infection and tube exposure following glaucoma valve implantation in patients with previous radiation therapy. To our knowledge, this is the second case in the literature of MRSA causing early postoperative infection following drainage device placement that required explantation.

The effect of mydriatic solutions on cognitive function.

INTRODUCTION: Anticholinergic and sympathomimetic ophthalmic solutions are used for mydriasis. These solutions have well-documented systemic side effects despite their topical administration. However, no studies have been conducted regarding the effect of mydriatic drops on cognitive function. The purpose of this study is to determine the effect, if any, of mydriatic drops on cognitive function, including memory, concentration, and orientation. METHODS: Participants were randomized into two groups using the technique of permuted block randomization, and randomization was stratified by gender, age, and education. Participants in Group 1 completed the Montreal Cognitive Assessment (MoCA) test with undilated pupils, while participants in Group 2 completed the MoCA test with dilated pupils. Administration time of the MoCA test was approximately 10 minutes, and each participant could receive a maximum of 30 points, with a score of 26 or greater being considered normal cognitive function. Dilation was achieved in both eyes with a combination of tropicamide 0.5% and phenylephrine 2.5%. RESULTS: There was no statistical difference between the MoCA scores of Group 1 and Group 2 (p = 0.65). In addition, MoCA scores were not statistically different between the glaucoma and non-glaucoma subpopulations within each group. MoCA test scores were shown to correlate with education (p = 0.004), age (p = 0.0003), and race (p = 0.03). Patients with confirmed or suspected glaucoma whom eyes dilated required 10.8 minutes to complete the MoCA test, while patients with no confirmed or suspected glaucoma whom eyes dilated required 8.5 minutes to complete the test (p = 0.02). DISCUSSION: Age, race, and education were found to be the most important factors affecting cognitive function in this study. There was no significant difference in the MoCA test scores of participants with confirmed or suspected glaucoma and participants without glaucoma. There was also no significant difference in the MoCA scores of dilated participants and non-dilated participants as a whole. However, dilation significantly increased the amount of time required to complete the MoCA test among the glaucoma and suspected-glaucoma population. The results of this study suggest that physicians should spend more time with dilated glaucoma patients while explaining medical conditions and treatment instructions in order to ensure that patients have adequate time to comprehend instructions for glaucoma management.