ABSTRACT
AIM: To observe the distribution of cone in the macular of healthy adult in different ages using adaptive optics scanning laser ophthalmoscope(AO-SLO)system, and analyze its relationship with age.METHODS: A total of 100 healthy examinees(200 eyes)in our hospital from June to July 2023 were selected, and they were divided into four groups according to their age, with 25 cases(50 eyes)in each group, including 18-30 years in group A, 31-40 years in group B, 41-50 years in group C, 51-65 years in group D. AO-SLO was performed in both eyes and cone density was measured.RESULTS: The density of cone in the foveal eccentricity of 3° and 2.4°×2.4° in each group was different(P<0.001), and the cone density in each area showed a relatively regular distribution characteristics, with the highest density in the temporal side, and the temporal>nasal>inferior>superior sides from high to low. The mean cone density in the macular area of both eyes was 14 144.38±1 082.40, 13 241.24±535.32, 12 930.29±727.73, and 10 907.50±490.86 cell/mm2, respectively(P<0.001), indicating that the cone density decreased with age. The correlation analysis showed that the mean cone density in the macular area was negatively correlated with age(r=-0.578, P<0.001).CONCLUSION: AO-SLO is a quantitative non-invasive detection of cones, and there is a negative correlation between cone density and age in healthy human. Furthermore, density of cone in healthy people over 50 years was significantly decreased.
ABSTRACT
Aim: To assess the variations in cone mosaic in myopia and its correlation with axial length (AL). Subjects and Methods: Twenty‑five healthy myopic volunteers underwent assessment of photoreceptors using adaptive optics retinal camera at 2° and 3° from the foveal center in four quadrants superior, inferior, temporal and nasal. Data was analyzed using SPSS version 17 (IBM). Multivariable regression analysis was conducted to study the relation between cone density and AL, quadrant around the fovea and eccentricity from the fovea. Results: The mean cone density was significantly lower as the eccentricity increased from 2° from the fovea to 3° (18,560 ± 5455–16,404 ± 4494/mm2 respectively). There was also a statistically significant difference between four quadrants around the fovea. The correlation of cone density and spacing with AL showed that there was a significant inverse relation of AL with the cone density. Conclusion: In myopic patients with good visual acuity cone density around the fovea depends on the quadrant, distance from the fovea as well as the AL. The strength of the relation of AL with cone density depends on the quadrant and distance.