The effect of age and cataract surgery on macular pigment optic density: a cross-sectional, comparative study.

BACKGROUND: To analyze the effects of age, cataract surgery and postoperative period on macular pigment optical density (MPOD).

METHODS: The study included cases referred to Ankara University Department of Ophthalmology, between April and June 2012, who had a transparent natural lens or had undergone cataract surgery at least a year ago with their best corrected visual acuity of ≥ 0.5 based on Snellen chart. Presence of an ocular disease that might affect lens, retina and optic nerve (cataract, macular degeneration, diabetic retinopathy, glaucoma etc.), cataract surgery within the previous year, light-colored iris, smoking and use of micronutrition supplementation were determined as exclusion criteria. After detailed opthalmologic examination of all patients, they were divided into three groups based on their age and their lens status as: group 1, patients < 50 years of age having a clear lens; group 2, patients > 50 years of age having a clear lens; and group 3, patients > 50 years of age who had cataract surgery. Age, gender, and postoperative period of the patients as well as the MPOD values of the eyes measured with heterochromatic flicker photometric (HFP) method (MacularMetricsTM) were included in the analysis.

RESULTS: Sixty-eight eyes of 37 cases with a mean age of 53.4 ± 15.3 years were enrolled in the study. Group 1 included 20 eyes of 10 cases (mean age 29.4 ± 9.5); group 2 included 32 eyes of 16 cases (mean age 60.3 ± 6.8); and group 3 included 16 eyes of 11 cases (mean age 65.2 ± 9.7). The mean macular pigment optical density value of all cases was 0.511 ± 0.192 log unit, while the mean MPOD values of groups 1, 2 and 3 were 0.570 ± 170, 0.528 ± 203 and 0.400 ± 180 log units, respectively. The mean MPOD values of the patients with clear lens aged < 50 and aged > 50 years did not reveal a statisticially significant difference (p = 1). However, the mean MPOD value of the cataract surgery group (group 3) was found to be statistically significantly lower than the group 1 and group 2 (p = 0.022, p = 0.039, respectively). The correlations between MPOD values and postoperative periods of the patients in group 3 showed that a decrease in MPOD values in parallel with duration of the postoperative period and this negative correlation was found to be statistically significant (r: -0.66, p = 0.005).

CONCLUSION: Our study has demonstrated that a significant correlation does not exist between age of the patients and MPOD values. MPOD values were lower than age-matched patients who had undergone cataract surgery and finally an inverse correlation existed between duration of the postoperative period after cataract surgery and MPOD values.