EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/865962
Supported by unrestricted educational grants from Allergan, Shire Pharmaceuticals, TearLab, and TearScience Figures 1 and 2 demonstrate the impact of OSD on preoperative measurements. Tear film optical power We also need to diagnose and treat OSD preoperatively to pre- vent postoperative aberrations. The greatest change in refrac- tive index occurs between the air and tear film. The tear film is the greatest ocular power surface on the eye. The cornea and tear film account for two-thirds of the eye's A-scans, and corneal topography, which will ultimately affect surgi- cal results. Epitropoulos et al. reported that patients with a hyperosmo- lar tear film showed significant variability in their average K readings and corneal astigmatism between measurements, resulting in significant differences in IOL power calculations. 2 Seventeen percent of hyper- osmolar eyes showed a greater than 1-D difference in cylinder between readings. Ten percent of patients in this study had an IOL power change greater than 0.5 D. do not have symptoms. If it is not diagnosed and treated before surgery, it can adversely impact patients' postoperative outcomes. Early detection In 272 eyes of 136 patients, Trattler et al. found that most had dry eye, and the majority did not have symptoms or had minimal symptoms. 1 Seventy-sev- en percent had abnormal corneal staining, and half had central corneal staining. If OSD is not identified and treated before cataract surgery, it can alter preoperative K readings, Diagnosis of widespread condition critical to surgical outcomes O cular surface disease (OSD) often is present in patients with cata- racts, but it may remain undetected if patients by Kenneth Beckman, MD Why catching OSD in advance matters to surgical patients Figure 1. A patient was referred for a toric IOL but was found to have blepharitis and mixed dry eye. The patient had 3 D of irregular astigmatism preoperatively, with irregular mires. Figure 2. The patient in Figure 1 used warm compresses, lid scrubs, preservative-free artificial tears, and azithromycin ophthalmic solution (b.i.d. x 2, then q.h.s. x 2 weeks). After treatment, astigmatism decreased to 0.5 D and was much more regular, and the patient was found not to be a toric IOL candidate. Kenneth Beckman, MD continued on page 4 3