title: Influence of coherence length, signal-to-noise ratio, log transform, and low-pass filtering on layer thickness assessment with OCT in the retina.
abstract: 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.
authors.affiliation: Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Nomdo M
authors.initials: NM
authors.lastname: Jansonius
authors.affiliation: Center for Optical Research and Education, Utsunomiya University, Utsunomiya, Tochigi, Japan.
authors.forename: Joel
authors.initials: J
authors.lastname: Cervantes
authors.affiliation: Center for Optical Research and Education, Utsunomiya University, Utsunomiya, Tochigi, Japan.
authors.forename: Maddipatla
authors.initials: M
authors.lastname: Reddikumar
authors.affiliation: Center for Optical Research and Education, Utsunomiya University, Utsunomiya, Tochigi, Japan.
authors.forename: Barry
authors.initials: B
authors.lastname: Cense
keywords: (100.0100) Image processing; (100.3008) Image recognition, algorithms and filters; (110.0113) Imaging through turbid media; (110.4500) Optical coherence tomography; (170.4460) Ophthalmic optics and devices; (170.4470) Ophthalmology