Comparison of macular thickness measurements between time-domain and spectral-domain optical coherence tomographies in eyes with and without macular abnormalities.

PURPOSE

To compare Stratus time-domain optical coherence tomography (OCT) with Cirrus spectral-domain HD-OCT for measuring macular thickness in eyes with and without macular abnormalities.

METHODS

Seventy-five eyes of 48 patients were included in the study. Forty-one eyes of 29 patients had a normal macular thickness, and 34 eyes of 26 patients had an abnormal macular thickness. Macular scans were performed by 2 examiners (E1 and E2) with both OCTs. The agreement between the two OCT systems and interrater repeatability of each OCT system were determined using the Bland-Altman method.

RESULTS

Mean agreement between the 2 OCTs as 1.96 × standard deviation of the mean difference between the measurements of central macular subfield was 21 μm in normal eyes and 36.8 μm in abnormal eyes. In five macular subfields, the agreement was significantly better in normal eyes. Cirrus HD-OCT repeatability was significantly better than Stratus in five macular subfields in normal eyes and in six macular subfields in abnormal eyes. The repeatability was significantly better in normal eyes in five macular subfields for Stratus and in three macular subfields for Cirrus HD-OCT.

CONCLUSION

The agreement between the two OCTs is low and varies in each macular subfield. Cirrus HD-OCT has shown a better repeatability than Stratus OCT, especially when measuring eyes with a thickened macula.