Comparison of Macular Thickness in Patients with Keratoconus and Control Subjects Using the Cirrus HD-OCT

Purpose. The aim of the present study was to compare macular thickness in patients with keratoconus (KC) with macular thickness in healthy subjects. Subjects and Methods. Twenty-six patients with KC and 52 control subjects were included. The macular structure was evaluated using a Zeiss Cirrus HD-OCT. The scan pattern used was 512 × 128, which covers an area of approximately 6 × 6 mm of the retina. The cube volume was assessed as well as macular thickness in each of the 9 sectors defined by the software. Results. The mean signal strength was significantly lower in the KC group (mean 8.4, range 6–10) compared with the control group (mean 9.7, range 7–10), P < 0.0001 (unpaired t-test). There were no significant differences in cube volume (unpaired t-test), cube average thickness, or macular thickness between the KC group and the control subjects in any of the retinal locations (one-way ANOVA). Conclusion. Macular structure as measured by OCT in KC subjects should be expected to lie within the range of age and sex matched controls.