Normative data set identifying properties of the macula across age groups: integration of visual function and retinal structure with microperimetry and spectral-domain optical coherence tomography.

PURPOSE: A normative database of functional and structural parameters of the macula from normal subjects was established to identify reference points for the diagnosis of patients with macular disease using microperimetry and scanning laser ophthalmoscope/spectral-domain optical coherence tomography (SD-OCT).
METHODS: This was a community-based, prospective, cross-sectional study of 169 eyes from subjects aged 21 years to 85 years with best-corrected visual acuity of 20/25 or better and without any ocular disease. Full-threshold macular microperimetry combined with the acquisition of structural parameters of the macula with scanning laser ophthalmoscope/SD-OCT was recorded (SD-OCT/scanning laser ophthalmoscope with add-on Microperimetry module; OPKO). Fixation, central, subfield, and mean retinal thickness were acquired together with macular sensitivity function. Thickness and sensitivity as primary outcome measures were mapped and superimposed correlating topographically differentiated macular thickness with sensitivity. Statistical evaluation was performed with age, gender, and ethnicity as covariates.
RESULTS: Subfield and mean retinal thickness and sensitivity were measured with macular microperimetry combined with SD-OCT and differentiated by macular topography and subjects' age, gender, and ethnicity. Mean retinal sensitivity and thickness were calculated for 169 healthy eyes (mean age, 48 ± 17 years). A statistically significant decrease in sensitivity was found only in the age group of participants ≥ 70 years and in peripheral portions of the macula in individuals aged ≥60 years and was more pronounced in the area surrounding the fovea than in the center of the macula, while retinal thickness did not change with age. No statistically significant differences in the primary outcome measures or their correlations were found when using gender or ethnicity as a covariate.
CONCLUSION: A database for normal macular thickness and sensitivity was generated with a combined microperimetry SD-OCT system as the basis for comparison of outcome parameters in patients with macular abnormality. Mean retinal sensitivity decreased significantly only in the age group of participants ≥ 70 years and in peripheral portions of the macula in individuals aged ≥60 years, with increasing distance from the fovea, while other parameters, their correlations and covariates, were not affected within the normative data set. No relationship was detected between retinal thickness and retinal sensitivity in the healthy macula.