Influence of coherence length, signal-to-noise ratio, log transform, and low-pass filtering on layer thickness assessment with OCT in the retina.

نویسندگان

  • Nomdo M Jansonius
  • Joel Cervantes
  • Maddipatla Reddikumar
  • Barry Cense
چکیده

Optical coherence tomography (OCT) images of the retina are inevitably affected by the finite width of the coherence function and noise. To make low-reflective layers visible, the raw OCT signal is log transformed; to reduce the effect of noise the images can be low-pass filtered. We determined the effects of these operations on layer thickness assessment, as a function of signal-to-noise ratio (SNR), by performing measurements in a phantom eye and modeling. The log transform appeared to be the key factor in a SNR-dependent overestimation of peak widths and a less predictive bias in the widths of low-reflective layers.

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عنوان ژورنال:
  • Biomedical optics express

دوره 7 11  شماره 

صفحات  -

تاریخ انتشار 2016