Evaluation of intraocular lens position during phacoemulsification using intraoperative spectral-domain optical coherence tomography.

PURPOSE: To assess the position of intraocular lenses (IOLs) at the end of standard phacoemulsification with intraoperative spectral-domain optical coherence tomography (SD-OCT). SETTINGS: Department of Ophthalmology, Rudolf Foundation Hospital, Vienna, Austria. DESIGN: Prospective case series. METHODS: Standard phacoemulsification with IOL implantation was performed. The Rescan 700 SD-OCT system was used for intraoperative imaging. The anterior segment of the eye was scanned using SD-OCT at the end of the surgery. The distance from the IOL optic center and the IOL optic edge to the posterior capsule was measured postoperatively using graphic software. RESULTS: The study comprised 74 patients (101 eyes). The mean axial length was 23.97 mm (range 21.43 to 28.61 mm). The mean IOL power was 20.39 diopters (D) (range 6.5 to 27.5 D). Contact between the IOL and posterior capsule was absent in 88 cases (87.13%), and partial or full contact was present in 13 cases (12.87%). The mean distance between the IOL central optic and posterior capsule was 0.71 pixel (range 0.06 to 1.38 pixels) in 99 cases (98.02%). In 42 cases (57.53%), partial contact between the IOL edges and the posterior capsule was noticed. The mean distance between the IOL edge and posterior capsule was 0.21 pixel (range 0.04 to 0.92 pixel). CONCLUSIONS: Intraoperative SD-OCT facilitated the imaging of IOL position during standard phacoemulsification. Contact between the IOL central optic and posterior capsule at the end of the surgery occurred rarely. Improved IOL design should be considered. FINANCIAL DISCLOSURE: Drs. Binder and Glittenberg are consultants to Carl Zeiss Meditech AG. None of the other authors has a financial or proprietary interest in any material or method mentioned.

Comparison of visual performance with blue light-filtering and ultraviolet light-filtering intraocular lenses.

PURPOSE: To compare the contrast sensitivity, glare, color perception, and visual acuity at different light intensities with yellow-tinted and clear intraocular lenses (IOLs) by different manufacturers. SETTING: Ludwig Boltzmann Institute of Retinology and Biomicroscopic Laser-Surgery, Department of Ophthalmology, Rudolf Foundation Clinic, Vienna, Austria. DESIGN: Comparative case series. METHODS: Eyes were randomized to 1 of the following IOLs: AF-1 (UY) (yellow tinted), AcrySof SN60AT (yellow tinted), AF-1 (UV) (clear), or AcrySof SA60AT (clear). One week and 2 months postoperatively, monocular contrast sensitivity function and color discrimination were tested and the corrected distance and near visual acuities were evaluated. All tests were performed under different light intensities (10 to 1000 lux). RESULTS: Of the 80 patients enrolled, 76 completed the study; there were 37 eyes in the yellow-tinted IOL group and 39 in the clear IOL group. There were no significant differences between yellow-tinted IOLs and clear IOLs except in color vision under mesopic conditions (10 lux). Patients with a yellow-tinted IOL made significantly more mistakes in the blue-light spectrum than patients with clear IOLs (P = .00015). There was no significant difference under photopic conditions (1000 lux). CONCLUSIONS: The yellow-tinted IOLs were equivalent to the clear IOLs in postoperative contrast sensitivity, visual acuity, and color perception under photopic conditions. Patients with yellow-tinted IOLs made statistically significantly more mistakes in the blue range under dim light than patients with clear IOLs.

Daytime levels of melatonin in patients with age-related macular degeneration.

PURPOSE: Melatonin (N-acetyl-5-methoxytryptamine) (MT) is a hormone that acts as an antioxidant. It is produced by the pineal gland and within the retina; its release is blocked by light entering the eye. We examined whether MT daytime levels differ between pseudophakic patients with age-related macular degeneration (ARMD) and pseudophakic subjects without any ocular pathology of the same age. METHODS: A prospective, cross-sectional, observational study was performed. Pseudophakic patients of the same age group were included. Patients underwent complete ophthalmic examinations and blood sampling between 08:00 and 10:00 hr. MT daytime value in the serum was the main outcome measure. RESULTS: Sixty-nine pseudophakic patients were included. Fifty patients with exudative and non-exudative ARMD were in the study group while 19 patients were controls. Patients with ARMD had significantly higher daytime levels of MT (P = 0.003). There were significant differences in MT daytime levels between the exudative and non-exudative forms (P = 0.009). MT values also correlated with the best-corrected visual acuity (r = -0.285, P = 0.019). CONCLUSION: These data indicate that pseudophakic patients with ARMD produce more MT during the day compared to pseudophakic subjects without ARMD. This may be caused by the reduced visual acuity in patients with ARMD, whereby less light reaches the photoreceptors, allowing MT secretion to continue during the day. Because MT also acts as an antioxidant and daytime levels are higher in patients with ARMD, these results might be interpreted as a rescue factor.

Effect of grid laser photocoagulation in diffuse diabetic macular edema in correlation to glycosylated haemoglobin (HbA1c).

BACKGROUND: Glycosylated haemoglobin (HbA1c) correlates with the amount of hyperglycemia in diabetic patients. High HbA1c levels often predict clinically significant macular edema (CSME), which then needs to be treated with grid laser photocoagulation. The question asked in this study was whether there is a correlation between the effect grid laser photocoagulation in diffuse diabetic macular edema and HbA1c, using an optical coherence tomography (OCT) for the evaluation of the retinal thickness. METHODS: A prospective, non-comparative case series was performed to find a correlation between the effect of grid laser photocoagulation in diffuse diabetic macular edema and HbA1c. Thirty eyes with CSME of diabetic patients were included in the study. Complete ophthalmic examinations and OCT were performed at baseline, 1 month, 3, and 6 months after grid laser photocoagulation therapy. HbA1c was measured at the end of study. RESULTS: Significance level was set at P<0.05. A significant difference in the foveal (P=0.02) and superior (P=0.021) retinal thickness 6 months after laser therapy, no correlation between HbA1c and retinal thickness after photocoagulation, and an insignificant decrease in visual acuity (P=0.9) were found. The correlation between foveal retinal thickness and visual acuity was P=0.24 6 months after treatment. CONCLUSION: There was no significant correlation between HbA1c and the effect of grid laser photocoagulation therapy in diffuse diabetic macular edema. The retinal thickness decreased significantly in the foveal and superior area 6 months after therapy. No correlation between the foveal retinal thickness and the visual acuity was found. The visual acuity did not increase after treatment. There are many factors influencing the retinal thickness, such as the blood pressure and the attached posterior hyaloid.