Motion artifact suppression in full-field optical coherence tomography

Abstract

Significant motion artifacts limit the performance of conventional full-field optical coherence tomography (FF-OCT) for in-vivo imaging. We present a theoretical and experimental study of those limitations. A new FF-OCT system suppressing most of artifacts due to sample motions is demonstrated using instantaneous phase shifting with nonpolarizing optics and pulsed illumination. The experimental setup is based on a Linnik-type interferometer illuminated by the superluminescence emission from a Ti:Al(2)O(3) waveguide crystal. En face tomographic images are calculated as a combination of two phase-opposed interferometric images acquired simultaneously by two CCD cameras placed at both outputs of the interferometer, with a spatial resolution of 0.8 microm x 1.6 microm (axial x transverse) and a detection sensitivity of approximately 60 dB.

Fourier spectrum analysis of full-field optical coherence tomography for tissue imaging

“…In fact, this en face imaging ability is one advantage of FFOCT over other OCT techniques. En face images are helpful in the cases where a horizontal cross-sectional image is needed [5] or the transverse distribution of biological structures has to be examined [11]. The en face view may also supply new information which may complement that provided by the depth view [49].…”

“…In initial efforts, an infrared light-emitting diode (LED) was used for illuminating a Linnik interference microscope [2][3][4][5]. A thermal light source was then used for illumination [6][7][8][9][10][11]. Because light sources with very short temporal and spatial coherence lengths are used in FFOCT, images at micrometre-scale spatial resolution in three dimensions have been generated for a leucocyte [6], and a fixed human oesophagus epithelium [8].…”

1550 nm Superluminescent Diode and Anti-Stokes Effect CCD camera based Optical Coherence Tomography for Full-Field Optical Metrology

“…A complex, multimodal system combining spectroscopic and polarization sensitive features was presented in [94]. A FF-OCT system, using pulse illumination, suppressing motion artifacts originating from sample lateral movements, was designed for in vivo imaging [95]. A single-shot FF-OCT is a technique able to record all phase-shifted interferograms simultaneously to increase speed of operation and a potentially suitable for in-vivo imaging [76,88].…”

Multi-penalty conditional random field approach to super-resolved reconstruction of optical coherence tomography images

“…Furthermore, the presence of speckle noise in the OCT images, which is an inherent characteristic of any interferometric imaging technique, gives the images a grainy appearance and limit the spatial resolution of the imaging method [4][5][6][7]. Degradation of the OCT spatial resolution can also be induced motion artifacts related to natural motion in the imaged object, or uncorrected nonlinearities in the scanning pattern [8,9]. All of the above mentioned factors can case degradation of the spatial OCT resolution which could obscure important fine morphological features in the imaged sample, thus making any further image processing and analysis such as segmentation, pattern recognition, etc., challenging [1].…”

“…Due to such fundamental hardware limitations, a number of different image enhancement techniques have been developed for improving the spatial resolution and quality of OCT images [14]. The majority of these methods focus on image enhancement based on a single data acquisition, which include: (i) de-convolution methods [15,16] that aim to reduce the effect of OCT PSF on the spatial resolution of acquired OCT image; (ii) different sampling methods in the Kspace for the reconstruction of OCT images with higher spatial resolution when the number of CCD pixels camera are not sufficient to generate high enough spatial resolution [17]; (iii) despeckling methods to compensate for the effect of speckle noise [5][6][7]18,19]; and (iv) motion reduction techniques to overcome the effect of sample motion in spatial resolution degradation of acquired OCT images [8,9,20].…”