Choroidal thickness tends to be thinner and negatively correlated with the degree of axial myopia in patients with myopia, and blood flow voids appear to increase, according to a study published in Eye and Vision. Secondary findings also reveal that less vascular density resulted in more myopia when the degree of anisometropia exceeded 1.50 D.
The cross-sectional analysis included a total of 44 participants aged 9 to 18 years (14.09±2.35). All patients were anisometropic with an interocular difference of at least 1.00D in their spherical equivalent refraction (SER), and a best-corrected logMAR visual acuity of 0 (20/20) or better in each eye.
Researchers obtained refractive error, intraocular pressure, axial length, central corneal thickness, and anterior chamber depth measurements. Choroidal structure images were analyzed via spectral domain optical coherence tomography (SD-OCT), and horizontal and vertical choroidal thicknesses were measured.
Choroidal thickness measurements in both the horizontal and vertical meridians were significantly thinner in the more myopic eye at all points (P ≤.001). Flow voids were determined to be higher in the more myopic eyes as well (P =.002). However, there was no significant difference in the vascular density of the choriocapillaris between the more and less myopic eyes of the same patient, unless the degree of anisometropia exceeded 1.50 D.
Study limitations include a cross-sectional design, the exclusion of patients with unilateral myopia, and the failure of SD-OCT to simultaneously analyze the vascular structure quickly and clearly.
Liu X, Lin Z, Wang F, et al. Choroidal thickness and choriocapillaris vascular density in myopic anisometropia. Eye Vis. Published online December 2, 2021. doi:10.1186/s40662-021-00269-9