The choroidal thickness in highly myopic eyes and its relationship with and the age and the axial length of the eyes

Abstract

Objective To investigate the choroidal thickness in highly myopic eyes and to correlate it with age and axial length of the eyes. Methods A total of 67 patients (132 eyes) with high myopia were studied in a clinical setting. Eyes were imaged using optical coherence tomography. Choroidal thickness was manually measured. Eleven measurements were taken at 500 mm intervals up to 2500 mm with capiler system. The axial length was also measured in all subjects using ultrasound pachymetry. Data were analyzed by statistic software SPSS 16.0. Results The mean age was 47.7±15.4 years (range, 20~74), mean axial length was 27.6±1.8mm (range, 24~35), mean spherical equivalent was -11.5±5.3 D (range, -6~-29). Mean macular choridal thickness was 119±80μm (range, 20~384). The choroid was thickest temporally (125μm), then subfoveally (119μm), and was thinnest in the nasal area (72μm). Linear correlation analysis results showed the age, axial length and spherical equivalent were negatively correlated with mean choroidal thickness (age r=-0.668, P <0.000; axial length r=-0.412, P <0.000; spherical equivalent r=-0.423, P <0.000). Conclusions The choroidal thickness in highly myopic eyes is thinner than emmetropic patients. Axial length, age and spherical equivalent are associated with choroidal thickness in high myopia. Key words: High myopia; Choroidal thickness; Optical coherence tomography