Eyeworld

JANUARY/FEBRUARY 2020 | EYEWORLD | 65 C Contact Hadjiargyrou: mhadji@nyit.edu Perry: hankcornea@gmail.com Wang: susan@arlenehowardpr.com by Vanessa Caceres Contributing Writer aureus as the most common bacteria found on punctal occluders. Comfortear (Delta Life Sciences), Parasol (Odyssey Medical), and Quintess (Alphamed), hydrophobic, silicone-based occluders that are 0.9 mm at the greatest diameter, were used in the study. "All three have a flat head, a thin neck, a thick cone-shaped base, and a central lumen," the researchers wrote. Each type of occluder was placed in 5 mL of nutrient broth with S. aureus cells, and the cultures were placed in a shaking 37-degree Cel- sius incubator. Each day for 7 days, 5 mL of the growing bacteria were removed and replaced with an equal amount of fresh nutrient broth so existing bacteria could continue to grow. After 7 days of exposure, the occluders were removed from the culture and placed in a microcentrifuge tube. Histological staining was then performed to help quantify the bacterial biofilm formation. Scanning electron microscopy (SEM) was used to evaluate the presence of bacteria and overall biofilm formation. During the exposure to bacteria, four oc- cluders of each type were used. Three of each P unctal occluders are commonly used to treat dry eye disease, but biofilm formation can be a problem with such occluders, leading to infection, inflam- mation, and intolerance. This led Michael Hadjiargyrou, PhD, and coresearchers to evaluate biofilm formation on three different types of punctal occluders. The in vitro study found that biofilm was more common on a punctal oc- cluder with the smoothest but grooved surface compared with two others that had rougher surfaces. 1 "Punctal occluders are particularly effective in patients with aqueous insufficiency and [dry eye disease], because they prevent outflow of tears through the punctum and preserve the natural tear lake," the researchers wrote. The term biofilm was described in 1978 by William Costerton, PhD, as "surface-at- tached microbial agglomerations," or a capsular polysaccharide that enables bacteria to attach to a device, according to the study. "The scaffold of the biofilm not only insulates bacteria from anti-infectives, disinfectant systems, and even our own white cells but also facilitates further bacterial adhesion and colonization," they wrote. Researchers focused on Staphylococcus Biofilm formation compared among three punctal occluders for dry eye "Ocular surface disease must be managed at the time of, or really prior to, cataract surgery," Dr. Gupta said, introducing a paper that looked at the impact of nodules and epithelial basement membrane dystrophy (EBMD) on refractive outcomes. This retrospective analysis included 39 eyes from 30 patients who were having a superficial keratectomy and/or phototherapeutic keratec- tomy for EBMD. Biometry was taken before the procedure(s) and again at least 30 days after- ward. There was a statistically significant change after pre-cataract surgical intervention in mean keratometry and IOL power closest to zero. There was an IOL spherical power change and cylinder change for toric candidates for both EBMD and Salzmann's after surgery to improve their ocular surface. "When you look at how significant the change is, the greatest change was in the 0.75 to 1.5 D of astigmatism," Dr. Gupta said, adding later that these findings drive home the impor- tance of identifying and treating these condi- tions preoperatively. Editors' note: This session is available at ascrs.org/ clinical-education/2019ondemand for those who attend- ed the 2019 ASCRS ASOA Annual Meeting. continued from page 64 About the doctors Michael Hadjiargyrou, PhD Professor and chair Department of Biological & Chemical Sciences New York Institute of Technology Old Westbury, New York Henry Perry, MD Ophthalmic Consultants of Long Island Rockville Centre, New York Ming Wang, MD Wang Vision 3D Cataract & LASIK Center Nashville, Tennessee continued on page 66 RESEARCH HIGHLIGHT

• Blank Page
• Blank Page (1)