Macular thickness measurements in healthy subjects with different axial lengths using optical coherence tomography

Purpose: To evaluate the retinal thickness of the macula in healthy subjects with different axial lengths. Methods: Included were 203 healthy subjects (116 males and 87 females). The axial length of the eyes ranged from 22.68 to 30.22 mm. Four optical coherence tomograms were obtained in a radial spoke pattern centered on the central fovea. Retinal thickness was calculated from the inner and outer retinal boundaries. The average retinal thickness in three circular areas surrounding the central fovea (350, 1,850, and 2,850 gm in diameter) was determined. Results: The retinal thickness in the three circular areas was not significantly correlated with the axial length of the eye (P = 0.10, P = 0.39, and P = 0.12). There also was no statistically significant difference found between the average thickness in emmetropic and low myopic, mildly myopic, and highly myopic eyes in the three circular areas (P = 0.35, P = 0.38, and P = 0.14). Conclusion: When eyes with pathologic myopia were excluded, the axial length of the eye was found not to influence the average retinal thickness in the macular area.