Purpose
To examine and compare the retinal thickness (RT) and choroid thickness (ChT) and their topographic variations across the posterior pole in high myopia and low myopia persons
Methods
A total of 25 subjectshad retinal and choroid measured using RTVue-100 optical coherence tomography (OCT). Fifteen of them had high myopia aged 16 to 39 years (mean age,27.94±1.13 years,SE: -9.50±2.00 diopters [D]), ten of them had low myopic aged from 18 to 36 years (mean age, 26.61±1.11,SE: -1.50±1.00 diopters [D]). Twelve radial OCT line scans centered on the fovea were assessed for each person. RT and CHT were delineated of nine macular sectors, according to the EDTRS by automated segmentation algorithm developed at the Wenzhou Medical University. Eight intra-retinal layers were semi-automatically segmented, including RNFL, GCL-IPL, INL, OPL,ONL, IS, OS, RPE layer.
Results
ChT was significantly thinner in high myopes compared to low myopes[j1] in all nine sectors. GCL-IPL was thinner in myopes in superior (1.5~3.0mm), temporal(1.5~3.0mm), inferior (1.5~3.0mm), nasal(1.5~3.0mm), RNFL was thinner in myopes in superior (1.5~3.0mm), temporal(1.5~3.0mm), inferior (1.5~3.0mm), INL was thinner in myopes in temporal (1.5~3.0mm), inferior (1.5~3.0mm), nasal (1.5~3.0mm), OPL had no difference in all the nine sectors between high myopes and low myopes, ONL was thinner in myopes in central foveal regions, superior(0.5~1.5mm), temporal (0.5~1.5mm), superior (1.5~3.0mm), temporal (1.5~3.0mm), inferior (1.5~3.0mm), IS layer was thicker in superior (0.5~1.5mm) and superior (1.5~3.0mm), OS layer was thicker in superior (1.5~3.0mm) and temporal (1.5~3.0mm), RPE layer was thicker in superior (0.5~3.0mm).
Conclusions
High myopic persons have significantly thinner choroids compared to low myopic persons of similar age, particularly in central foveal regions. GCL-IPL, RNFL,INL were thinner in some region, especially outer region in myopia persons, and OPL had no difference in statistic in all the nine sectors between the high myopes and low myopes, OS, IS and RPE layers were thicker in some regions in high myopia persons.