Spatially deconvolved optical coherence tomography

Abstract

In this paper we present spatially mapped point-spread function (PSF) measurements of an optical coherence tomography (OCT) instrument and subsequent spatial deconvolution. The OCT B-scan image plane was divided into 2400 subimages, for which PSFs were determined from OCT measurements of a specially designed phantom. Each PSF was deconvolved from its corresponding subimage of the phantom using the Lucy-Richardson algorithm. Following deconvolution, all of the subimages were reassembled to form a final deconvolved image, from which the resolution improvement was quantitatively assessed. The lateral resolution was found to improve by 3.1 microm compared to an axial resolution enhancement of 4.5 microm. The spatial uniformity of both axial and lateral resolution was also observed to increase following deconvolution, demonstrating the advantage of deconvolving local PSFs from their associated subimages.

Variations in optical coherence tomography resolution and uniformity: a multi-system performance comparison

“…Therefore, this approach has significant promise as a standardized method for objective, quantitative evaluation of OCT systems performance, or as a method for improving OCT image quality through PSF deconvolution [19] or by facilitating PSF engineering [32].…”

“…The FeO particles have a diameter of 300-800 nm. Further description of this phantom and its fabrication is provided in a prior article [19]. The third phantom (labeled "Silica") incorporated silica microspheres (1.5 μm mean diameter, MSS001a, Whitehouse Scientific, Ltd., UK) embedded in an epoxy matrix (Araldite DBF resin + Araldite HY951 hardener, Huntsman International, LLC).…”

“…This approach involves characterizing the shape of a point spread function (typically an irregular one) and then modifying system characteristics to optimize the shape of the PSF, thus improving system resolution [17]. The use of highly scattering dispersed particles for OCT system resolution evaluation has been studied by several groups [1,2,[18][19][20]. In these studies, randomly distributed particles are used to evaluate and quantify the PSF along all three spatial axes.…”

Artefact reduction for cell migration visualization using spectral domain optical coherence tomography

“…Optical coherence microscopy (OCM) using en face TD detection offers the benefit of coherence gating [1,8]. Acquisition speed and sensitivity was increased by using spectral domain (SD) OCT [9] and with numerical techniques transversal resolution could be retained outside focus region [10,11]. One of the limits of 3D deconvolution is that it tends to reduce the sensitivity by the introduction of noise [11] and because of the required high phase stability it could not be applied to in vivo imaging [10].…”

“…Acquisition speed and sensitivity was increased by using spectral domain (SD) OCT [9] and with numerical techniques transversal resolution could be retained outside focus region [10,11]. One of the limits of 3D deconvolution is that it tends to reduce the sensitivity by the introduction of noise [11] and because of the required high phase stability it could not be applied to in vivo imaging [10]. SD-OCT has been applied to cellular imaging [2][3][4][5] and also offers the benefit of increased phase stability [12][13][14][15].…”