Retinal thickness of myopic eyes determined by spectralis optical coherence tomography.

Aims: To determine the relationship between the macular thickness and volume determined by spectral domain optical coherence tomography (SD-OCT) and the refractive error (RE) and axial length (AL).

Methods: 48 eyes of 24 healthy Japanese subjects were examined. The REs (spherical equivalent) were measured with the Tonoref RKT-7000 autorefractometer (Nidek Inc, Aichi, Japan), and the ALs were determined by the IOL-Master (Carl Zeiss Meditec Inc, Dublin, California, USA). The thicknesses and volumes of the central, inner, and outer macular areas were measured by Spectralis SD-OCT (Heidelberg Engineering, Heidelberg, Germany). The correlations between the macular thickness and volume and the RE and AL were determined by linear regression analyses.

Results: The average central foveal thickness (within 1 mm) was 278.7±10.8 μm and the volume was 0.22±0.01 mm(3). The foveal thickness was negatively correlated with the RE and positively correlated with the AL (p<0.01 for both). Similar correlations were also found for the volume of the central macular areas.

Conclusions: The significant correlation of the foveal thickness and the RE and AL in healthy eyes should be considered when these parameters are evaluated in eyes with retinal diseases.