Abstract
Purpose::
To investigate any changes in thickness of the fovea and the peripapillary RNFL, according to axial length, corneal power, and degree of myopia.
Methods::
Sixty five Korean adults (130 eyes) between 23 and 26 years of age were selected as the test subjects. Thirty eight test subjects were male, and twenty seven were female. Anyone having glaucoma or any other identified ocular diseases was excluded from the test. For all subjects, refractive error, axial length and corneal power were measured. Patients who scored manifest refraction measurements between 0 to -2D were classified as group one(emmetropia and low myopia), those who scored between -2 to -5D were classified as group two (moderate myopia), and those who scored more than -5D were classified as group three (high myopia). Using the OCT, thicknesses of the fovea and the peripapillary RNFL were measured for all subjects.
Results::
The thickness of the fovea was 142.16 ± 8.99 um in group one (45 eyes), 153.58 ± 17.63 um in group two (43 eyes) and 158.86 ± 11.93 um in group three (28 eyes). This data showed significant differences in thicknesses of the fovea among three groups. The average thickness of the peripapillary RNFL was 113.29 ± 10.80 um in group one, 103.85 ± 14.48 um in group two and 100.74 ± 9.15 um in group three. A statistically significant difference between group one and the other two groups (p<0.05) was identified. As the axial length increased, the thickness of the fovea also increased, yet the thickness of the peripapillary RNFL decreased(p<0.05). Statistically, there was no correlation between corneal power and the thickness of fovea. Also no correlation was found between corneal power and the thickness of peripapillary RNFL.
Conclusions::
In this study, as the degree of myopia and axial length increased, the data demonstrated that the thickness of the fovea also increased, and conversely, the thickness of the peripapillary RNFL decreased. Therefore, when interpreting the results of the OCT in the clinic, careful consideration should be given to these changes associated with myopia.
Keywords: nerve fiber layer • myopia