Variation in subfoveal choroidal thickness in patients with high myopia complicated by choroidal neovascularization

The aims of this study was to observe the variation in subfoveal choroidal thickness (SFCT) in patients with highly myopic macular complicated by choroidal neovascularization (CNV) and to compare choroidal thickness in these eyes with highly myopic eyes without CNV, matched with the others group by ages, genders, eye axial length and diopter. 72 cases with 72 eyes, confirmed with high myopia in the ophthalmology clinic outpatient of The First Affiliated Hospital of Zhengzhou Univesity from September 2013 to August 2014, were collected in this study. 36 cases with 36 eyes in the group without CNV and similarly, 36 cases with 36 eyes in the group with CNV. Eye axial length, diopter, eye ground and spectral-domain optical coherence tomography examinations were performed on the two groups. Subfoveal choroidal thickness observed in high myopia without CNV group was (102.38 +/- 39.05) mu m, while that in high myopia with CNV group was (61.72 +/- 22.28) mu m. The difference of choroidal thickness (CT) between the each two groups was statistically significant (t=5.16, P<0.05). A statistically significant negative correlation was found between CT and eye axial length. In high myopia group, r=-4.13 and P=0.012, while in high myopia with CNV group, r=-5.52 and P=0.000. The development of high myopia may be associated with the choroid blood perfusion. The thinning of choroidal thickness leaded by reduced choroid blood perfusion may play a role in the occurrence of choroidal neovascularization.