Grayscale and proportion-corrected optical coherence tomography images.

H Ishikawa; R Gürses-Ozden; S T Hoh; H L Dou; J M Liebmann; R Ritch

PubMed · 10847500

Grayscale and proportion-corrected optical coherence tomography images.

H Ishikawa·R Gürses-Ozden·S T Hoh·H L Dou·J M Liebmann·R Ritch

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.

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BibTeX RIS

H Ishikawa, R Gürses-Ozden, S T Hoh, H L Dou, J M Liebmann, R Ritch. Grayscale and proportion-corrected optical coherence tomography images.. https://pubmed.ncbi.nlm.nih.gov/10847500/

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