| Summary: | Aim: To assess the functional aspects of cone mosaic and correlate cone packing with retinal sensitivity utilizing microperimetry in emmetropes at different eccentricities.Methods: Twenty-four healthy volunteers underwent microperimetry (MAIA Centervue, Italy) and assessment of photoreceptors using adaptive optics retinal camera, rtx1 (Imagine Eyes, Orsay, France), at 2 and 3 degrees from the foveal centre in 4 quadrants: superior, inferior, temporal, and nasal. Data was analyzed using SPSS version 17 (IBM). Spearman's correlation tests were used to establish correlation between mean cone packing density and retinal sensitivity at different quadrants.Results: Thirteen females and 11 males (age range 20-40 years) were included. The cone density was found to be significantly different among all quadrants (temporal = 25786.68/mm(2) ± 4367.07/mm(2), superior = 23009.35/mm(2) ± 5415.81/mm(2), nasal = 22838.09/mm(2) ± 4166.22/mm(2), and inferior = 21097.53/mm(2) ± 4235.84/mm(2)). A statistical significance (P < 0.008) was found between orthogonal meridians, that is, temporal, nasal (48624.77/mm(2))> superior, inferior (44106.88/mm(2)). A drop in retinal sensitivity was observed as the eccentricity increased (P < 0.05). It was also found that as cone packing density decreased retinal sensitivity also decreased (P < 0.05) in all quadrants. This was observed at both 2 and 3 degrees.Conclusion: It is of crucial importance to establish normative variations in cone structure-function correlation. This may help in detection of subtle pathology and its early intervention.
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