Enhanced Depth Imaging Optical Coherence Tomography: A Study of the Choroid in High Axial Myopia

Abstract

igh myopia is one of the main causes of visual impairment worldwide. About 1% of the population has high myopia. There is significant evidence from research, that the development of refractive errors is associated with changes in the structural characteristics of the choroid. It is essential to understand how choroidal thickness in xdifferent regions of the macula vary with refractive error, axial length, to fully appreciate the effects of the disease process on the choroid. The purpose of this study is to evaluate the choroid by enhanced depth imaging optical coherence tomography, as regards its morphology and thickness in high axial myopic patients and compared with healthy subjects. The study included 101 high axial myopic eyes (more than -6.00 diopters; group I). This group was subdivided according to the level of myopia into: group Ia: from -6 diopters till -10 diopters, group Ib: from more than -10 diopters till -15 diopters, group Ic: from more than -15 diopters till -20 diopters and group Id: from above -20 diopters. It also included 101 emmetropes as controls (group II). All subjects underwent full ophthalmologic examination in addition to axial length measurement and enhanced d