1. Valentin M. Gelikonov

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    1. Mentioned In 67 Articles

    2. Application of Phase Correction for Compensation of Motion Artifacts in Spectral-Domain Optical Coherence Tomography

      Application of Phase Correction for Compensation of Motion Artifacts in Spectral-Domain Optical Coherence Tomography
      The application of computational methods to correct distortions in spectral-domain optical coherence tomography due to fast probe movements relative to a studied object is described. This technique is intended for use in endoscopy or in the study of external biological tissues using a handheld probe. The effectiveness of the method was confirmed experimentally.
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    3. Low-scattering volumes visualisation from optical coherence tomography data and its applications in otolaryngology

      Low-scattering volumes visualisation from optical coherence tomography data and its applications in otolaryngology
      The method for visualization of the low-scattering objects inside the bulk of the high-scattering tissue is presented. The method can contrast the low-scattering object of interest not only from the high scattering surroundings but from the noise region below the tissue image as well. The proposed method was applied for the visualization of the rodent and human cochlea volume.
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    4. Numerical method for axial motion artifact correction in retinal spectral-domain optical coherence tomography

      Numerical method for axial motion artifact correction in retinal spectral-domain optical coherence tomography
      A numerical method that compensates image distortions caused by random fluctuations of the distance to an object in spectral-domain optical coherence tomography (SD OCT) has been proposed and verified experimentally. The proposed method is based on the analysis of the phase shifts between adjacent scans that are caused by micrometer-scale displacements and the subsequent compensation for the displacements through phase-frequency correction in the spectral space. The efficiency of the method ...
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    5. Optical coherence angiography for pre-treatment assessment and treatment monitoring following photodynamic therapy: a basal cell carcinoma patient study

      Optical coherence angiography for pre-treatment assessment and treatment monitoring following photodynamic therapy: a basal cell carcinoma patient study
      Microvascular networks of human basal cell carcinomas (BCC) and surrounding skin were assessed with optical coherence angiography (OCA) in conjunction with photodynamic therapy (PDT). OCA images were collected and analyzed in 31 lesions pre-treatment, and immediately/24hours/312 months post-treatment. Pre-treatment OCA enabled differentiation between prevalent subtypes of BCC (nodular and superficial) and nodular-with-necrotic-core BCC subtypes with a diagnostic accuracy of 78%; this can facilitate more accurate biopsy reducing sampling ...
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    6. Elimination of Artifacts Caused by the Nonidentity of Parallel Signal-Reception Channels in Spectral Domain Optical Coherence Tomography

      Elimination of Artifacts Caused by the Nonidentity of Parallel Signal-Reception Channels in Spectral Domain Optical Coherence Tomography
      We study the causes of artifact appearance in the images obtained by the method of spectral domain optical coherence tomography with parallel reception of the optical-spectrum components, which are manifested in repetition and overlay of the structural elements of the images of the studied medium with a shift in depth. It is shown that nonidentity of the transfer characteristics of the channels of the multichannel photoreceiving elements is one of ...
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    7. Compensation for the Influence of Fluctuations in the Distance to the Object During Noncontact Probing in Spectral Domain Optical Coherence Tomography

      Compensation for the Influence of Fluctuations in the Distance to the Object During Noncontact Probing in Spectral Domain Optical Coherence Tomography
      We propose and experimentally test a numerical method for correction of the influence of fluctuations in the distance to objects during noncontact probing in optical coherence tomography. The method is based on the analysis of phase shifts of the neighboring scans, which are due to microscale displacements, and further compensation for these displacements by using phasefrequency correction in the spectral domain. Unlike the known correlation methods, the proposed method does ...
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    8. Improving the Transverse Resolution of Optical Coherence Tomography with a Finite Impulse Response Filter and a Series of Numerically Refocused Images

      Improving the Transverse Resolution of Optical Coherence Tomography with a Finite Impulse Response Filter and a Series of Numerically Refocused Images
      Among the numerous methods for improving the informative value of the optical coherence tomography (OCT), a special place is taken by the methods for increasing the spatial resolution of the resulting images. Increasing the resolution allows one to identify more clinically significant structures in OCT images and thus improve the diagnostic value of OCT. Since the transverse resolution of OCT images is determined by the physical principles different from those ...
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    9. Measurement and Compensation for the Amplitude and Phase Spectral Distortions of an Interference Signal in Optical Coherence Tomography for the Relative Optical-Spectrum Width Exceeding 10%

      Measurement and Compensation for the Amplitude and Phase Spectral Distortions of an Interference Signal in Optical Coherence Tomography for the Relative Optical-Spectrum Width Exceeding 10%
      We describe a universal method of compensating for the arbitrary dispersion in the spectral and time domain optical coherence tomography systems. In combination with the amplitude method of correcting the optical-spectrum irregularities, this approach allows one to obtain the spectrally determined resolution if the instrument function is close to the Gaussian one. The efficiency of the method is demonstrated in the time and spectral domain optical coherence tomographies with the ...
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    10. Digital refocusing in optical coherence tomography using finite impulse response filters

      Digital refocusing in optical coherence tomography using finite impulse response filters
      A finite impulse response filter, which shifts the focal plane in optical coherence tomography (OCT) images, is proposed. Since several OCT images with the focal plane in various positions can be fused into one image with increased lateral resolution, such a filter facilitates the creation of an OCT system with numerically increased lateral resolution, operating in real-time, i.e. showing one OCT B-scan with increased lateral resolution while collecting data ...
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    11. Time domain optical coherence tomography is a useful tool for diagnosing otitis media with effusion

      Time domain optical coherence tomography is a useful tool for diagnosing otitis media with effusion
      The usability of time-domain optical coherence tomography equipped with a flexible endoscopic probe for detecting effusion in the tympanic cavity is shown in the clinical environment. The possibility of assessing the dynamic properties of effusion, particularly its contained scatterers' mobility, is shown in real clinical cases. A method of comparative assessment of scatterers' mobility is proposed.
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    12. Optical coherence tomography‐based angiography device with real‐time angiography B‐scans visualization and hand‐held probe for everyday clinical use

      Optical coherence tomography‐based angiography device with real‐time angiography B‐scans visualization and hand‐held probe for everyday clinical use
      This work is dedicated to the development of the OCT system with angiography for everyday clinical use. Two major problems were solved during the development: compensation of specific natural tissue displacements, induced by contact scanning mode and physiological motion of patients (eg, respiratory and cardiac motions) and online visualization of vessel cross‐sections to provide feedback for the system operator.
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    13. Cross-Polarization Optical Coherence Tomography with Active Maintenance of the Circular Polarization of a Sounding Wave in a Common Path System

      Cross-Polarization Optical Coherence Tomography with Active Maintenance of the Circular Polarization of a Sounding Wave in a Common Path System
      We consider a cross-polarization optical coherence tomography system with a common path for the sounding and reference waves and active maintenance of the circular polarization of a sounding wave. The system is based on the formation of birefringent characteristics of the total optical path, which are equivalent to a quarter-wave plate with a 45 orientation of its optical axes with respect to the linearly polarized reference wave. Conditions under which ...
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    14. Equidistant Recording of the Spectral Components in Ultra-Wideband Spectral-Domain Optical Coherence Tomography

      Equidistant Recording of the Spectral Components in Ultra-Wideband Spectral-Domain Optical Coherence Tomography
      We develop an effective method for reducing nonequidistance when recording the spectral components of an interference signal in ultra-wideband spectral-domain optical coherence tomography. For this purpose, a corrector consisting of two identical prisms is used in a diffraction-grating spectrometer. The corrector rotation with respect to the diffraction-grating plane and a variation in the angle between the corrector elements allow one to adjust the equidistant spatial distribution of the spectral components ...
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    15. A data-acquisition and control system for spectral-domain optical coherence tomography with a speed of 91 912 A-scans/s based on a USB 3.0 interface

      A data-acquisition and control system for spectral-domain optical coherence tomography with a speed of 91 912 A-scans/s based on a USB 3.0 interface
      We describe a system of optical spectrum registration at the output of an interferometer with controlled phase shifts for an experimental device intended for visualizing the internal structure of an optically turbid specimen, using the method of spectral domain optical coherence tomography. A device for spectral domain optical coherence tomography based on a common-path optical scheme with a USB 3.0 interface for inputting data into a computer has been ...
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  2. About Valentin M. Gelikonov

    Valentin M. Gelikonov

    Valentin M. Gelikonov graduated from the Gorky State University in 1966 and received his Ph.D. in 1985 and his Dr. Sc. in physics and mathematics in 2007. His fields of scientific interests include high sensitive optical measurements, low coherence fiber-optic interferometry, optical coherence tomography (OCT). He is Head of Department of Nonlinear Dynamics and Optics at the Institute of Applied Physics RAS. He has published about 120 papers in the fields of laser measurements, fiber-optic interferometry, and OCT. Dr. Gelikonov received the State Prize of the Russian Federation in Science and Technology in 1999.