Iris thickness measurements in patients with diabetic retinopathy.

PURPOSE: The aim of the study was to investigate iris alterations in diabetic retinopathy (DR). METHODS: Sixty-nine eyes of 69 patients were recruited and three groups of patients were examined: proliferative DR (n = 25), non-proliferative DR (n = 21) and healthy controls (n = 23). Macular optical coherence tomography (OCT), anterior segment iris OCT, and slit lamp digital camera photographs were taken. The thicknesses of the iris at a distance of 1 mm, 2 mm, and 3 mm from pupil margin were measured via iris OCT. Iris crypt count, furrow extent, color tone and collarette/diameter ratio were measured by means of anterior segment photography. Visual acuity, refractive error, intraocular pressure, and numbers of intravitreal injections were also recorded. RESULTS: The iris thickness measurements at 1 mm from pupil margin were significantly correlated with the macular thickness measurements (r = 0.32, p = 0.016). In the proliferative DR group, total number of injections were significantly correlated with the iris thickness measurements at 1 mm (r = 0.25, p = 0.04). The iris thickness measurements at distances 1 mm, 2 mm, and 3 mm from the pupil margin were similar in all of the groups (p > 0.05). Iris thickness did not correlate with age, intra-ocular pressure and collarette iris ratio in all the participants (p > 0.05). CONCLUSION: Iris thickness is similar in diabetic patients and healthy controls. Meanwhile, iris thickness near the pupillary margin is positively correlated with macular thickness.

Oxidative Stress and Genotoxicity in Pterygium: A Systemic Investigation.

OBJECTIVES: To perform a systemic investigation on oxidative stress and DNA damage in patients with primary pterygium. METHODS: This prospective cross-sectional study included 32 patients with primary pterygium (60.1±2.0 years of age) and 33 age- and sex-matched (58.8±2.2 years of age) control subjects (P>0.05). A commercial kit was used for measuring serum total oxidant status (TOS) and total antioxidant status (TAS). The comet assay was performed after lymphocyte isolation from venous blood to quantitate DNA damage. Tail length (TL), tail intensity (TI), and tail moment (TM) were used for statistical analysis as parameters of DNA damage. RESULTS: In the pterygium group, TOS and TAS were significantly higher when compared with those of the control group (P=0.019 and P=0.005, respectively). In terms of DNA damage, patients with pterygium had higher TL, TI, and TM than in the control subjects (P<0.0001 for all). CONCLUSIONS: Although current literature focuses on local factors in pterygium pathogenesis, patients with pterygium seem to have increased systemic oxidative status (and compensatory antioxidant response) and genotoxicity, which might create a predisposition for pterygium development.

Quantitative assessment of macular contraction and vitreoretinal interface alterations in diabetic macular edema treated with intravitreal anti-VEGF injections.

BACKGROUND: Macular contraction after anti-vascular endothelial growth factor (anti-VEGF) injections for diabetic macular edema (DME) was evaluated by documenting the displacement of macular capillary vessels and epiretinal membrane (ERM) formation. METHODS: A total of 130 eyes were included in this retrospective study. The study group consisted of 63 eyes which had intravitreal anti-VEGF injections for DME, and the control group included 67 eyes without central DME. The study and the control groups were well balanced in terms of diabetes duration and HbA1c. The distances between the bifurcation of the macular capillary retinal vessels were measured, and ERM status was evaluated based on spectral-OCT findings on the initial and final visit. RESULTS: In the study group, the mean number of injections was 4.7 ± 2.6 (3-14). The mean follow-up time was 16.7 ± 7.8 months in the study group whereas it was 20.7 ± 10.9 months in the control group (p = 0.132). The change in distance measurements between the reference points on macular capillary vessels was significant in all lines except line c (p < 0.05 for lines a, b, d, e, and f) in the study group whereas it was significant in only line e in the control group (p = 0.007, paired samples test). However, when the change in macular thickness was accounted as a confounding factor, the change in distances between the references points from the initial visit to the final visit lost its significance (repeated measures ANCOVA, p > 0.05). During follow-up, the number of cases with ERM changed from 10 to 12 in the study group whereas it remained three in the control group. CONCLUSION: There was a displacement of macular capillary vessels which was associated with the change in macular thickness in eyes having anti-VEGF injections for DME. The number of ERM cases did not change significantly during the follow-up.