A maximum a-posteriori (MAP) estimator for signal amplitude of optical coherence tomography (OCT) is presented. This
estimator provides an accurate and low bias estimation of the correct OCT signal amplitude even at very low signal-tonoise
ratios. As a result, contrast improvement of retinal OCT images is demonstrated. In addition, this estimation method
allows for an estimation reliability to be calculated. By combining the MAP estimator with a previously demonstrated
attenuation imaging algorithm, we present attenuation coefficient images of the retina. From the reliability derived from
the MAP image one can also determine which regions of the attenuation images are unreliable. From Jones matrix OCT
data of the optic nerve head (ONH), we also demonstrate that combining MAP with polarization diversity (PD) OCT
images can generate intensity images with fewer birefringence artifacts, resulting in better attenuation images. Analysis of
the MAP intensity images shows higher image SNR than averaging.
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