Abstract
Purpose: :
Standardised evaluation of retinal thickness is essential for the course of retinal diseases, and the analysis in clinical studies. Up to now most ophthalmologists use Zeiss OCT III for evaluation of retinal thickness. In the past months fourier domain OCT's are getting more and more popular. Aim of this study was to compare the retinal thicknesses measured with OCT III and Heidelberg Spectralis OCT.
Methods: :
Retinal thickness of 20 eyes of 10 healthy subjects and 10 eyes of 8 diabetic maculopahty patients have been measured with Zeiss OCT III and Heidelberg Spectralis OCT. Central retinal thickness, and superior, temporal, inferior and nasal 2 mm zones have been evaluated and compared.
Results: :
Central and paracentral retinal thickness was statistically significant thicker in Heidelberg Spectralis OCT than in Zeiss OCT III. Central retinal thickness was in healthy patients 229,625µm (SD 27,55) in OCT III and 279,75µm (SD 26,080918) in Spectralis, superior 272,75 µm (SD 18,79) in OCT III 341,62µm (SD 25,52) in Spectralis, nasal 276,875µm (SD 18,24) in OCT III and 333,25 µm (SD 22,86) in Spectralis, temporal 273,625 (SD 9,79) and 336,625µm (SD 19,94) and inferior 277,75µm (SD 18,26) in OCT III and 332,875 µm (SD 22,53). Also retinal thickness was thicker in diabetic patients measured with Spectralis OCT than measured with OCT III. The central retinal thickness was in OCT III 247 µm (SD 38,31), and for the Heidelberg Spectralis 308,66µm (SD 37,806525).
Conclusions: :
Spectralis OCT seems to measure thicker retinal thicknesses than OCT III. In all patients the retina was about 40µm thicker. One reason could be different measure schemes of the different companies. Spectralis OCT seems to measure automatically under the pigment epithelium. This could be one reason for the differences.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical • diabetic retinopathy