Grayscale and proportion-corrected optical coherence tomography images

Ophthalmic Surg Lasers. 2000 May-Jun;31(3):223-8.

Abstract

Background and objective: The commercially available optical coherence tomography (OCT) scanner displays images in a pre-set window regardless of the projected scan length on the retinal surface. The aim of this study was to demonstrate the true dimensions of proportion-corrected OCT images and the additional information present in grayscale images.

Materials and methods: OCT raw data were exported to an IBM-compatible PC and processed to show grayscale and proportion-corrected images using an automated software of our own design.

Results: Eyes with cystoid macular edema and retinal pigment detachment were analyzed. Grayscale images showed a finer gradation of signal reflectance. Scan lengths of 2, 4, 6, and 8 mm on the retinal surface showed different qualitative appearances using proportion-corrected software from the printed or on-screen images.

Conclusions: Grayscale OCT images can be used to demonstrate additional information not present in false-color images. The disparity between the standard OCT image format and proportion-corrected images emphasizes the need for quantitative rather than qualitative evaluation of retinal dimensions and internal reflectance.

Publication types

  • Comparative Study

MeSH terms

  • Algorithms
  • Diagnostic Techniques, Ophthalmological*
  • Humans
  • Interferometry
  • Light
  • Macular Edema / pathology
  • Pigment Epithelium of Eye / pathology
  • Retina / pathology*
  • Retinal Detachment / pathology
  • Tomography / methods*
  • Tomography / standards