1. Maciej Wojtkowski

    0 Comments Leave a Comment

    1-15 of 108 1 2 3 4 5 6 7 8 »
    1. Mentioned In 108 Articles

    2. Feature Of The Week 10/08/2017: Optical Coherence Microscopy as a Novel, Non-Invasive Method for the 4D Live Imaging of Early Mammalian Embryos

      Feature Of The Week 10/08/2017: Optical Coherence Microscopy as a Novel, Non-Invasive Method for the 4D Live Imaging of Early Mammalian Embryos
      Imaging of living cells based on traditional fluorescence and confocal laser scanning microscopy has delivered an enormous amount of information critical for understanding biological processes in single cells. However, the requirement for a high numerical aperture and fluorescent markers still limits researchers ability to visualize the cellular architecture without causing short- and long-term photodamage. Optical coherence microscopy (OCM) is a promising alternative that circumvents the technical limitations of fluorescence imaging ...
      Read Full Article
    3. Classification of biological micro-objects using optical coherence tomography

      Classification of biological micro-objects using optical coherence tomography
      We report on the development of a technique for differentiating between biological micro-objects using a rigorous, full-wave model of OCT image formation. We model an existing experimental prototype which uses OCT to interrogate a microfluidic chip containing the blood cells. A full-wave model is required since the technique uses light back-scattered by a scattering substrate, rather than by the cells directly. The light back-scattered by the substrate is perturbed upon ...
      Read Full Article
    4. Optical coherence microscopy as a novel, non-invasive method for the 4D live imaging of early mammalian embryos

      Optical coherence microscopy as a novel, non-invasive method for the 4D live imaging of early mammalian embryos
      Imaging of living cells based on traditional fluorescence and confocal laser scanning microscopy has delivered an enormous amount of information critical for understanding biological processes in single cells. However, the requirement for a high numerical aperture and fluorescent markers still limits researchers ability to visualize the cellular architecture without causing short- and long-term photodamage. Optical coherence microscopy (OCM) is a promising alternative that circumvents the technical limitations of fluorescence imaging ...
      Read Full Article
    5. Twenty-five years of optical coherence tomography: the paradigm shift in sensitivity and speed provided by Fourier domain OCT

      Twenty-five years of optical coherence tomography: the paradigm shift in sensitivity and speed provided by Fourier domain OCT
      Optical coherence tomography (OCT) has become one of the most successful optical technologies implemented in medicine and clinical practice mostly due to the possibility of non-invasive and non-contact imaging by detecting back-scattered light. OCT has gone through a tremendous development over the past 25 years. From its initial inception in 1991 [Science 254 , 1178 (1991)] it has become an indispensable medical imaging technology in ophthalmology. Also in fields like cardiology ...
      Read Full Article
    6. Spectrometer calibration for spectroscopic Fourier domain optical coherence tomography

      Spectrometer calibration for spectroscopic Fourier domain optical coherence tomography
      We propose a simple and robust procedure for Fourier domain optical coherence tomography (FdOCT) that allows to linearize the detected FdOCT spectra to wavenumber domain and, at the same time, to determine the wavelength of light for each point of detected spectrum. We show that in this approach it is possible to use any measurable physical quantity that has linear dependency on wavenumber and can be extracted from spectral fringes ...
      Read Full Article
    7. Extended-focus optical coherence microscopy for high-resolution imaging of the murine brain

      Extended-focus optical coherence microscopy for high-resolution imaging of the murine brain
      We propose a new method and optical instrumentation for mouse brain imaging based on extended-focus optical coherence microscopy. This in vivo imaging technique allows the evaluation of the cytoarchitecture at cellular level and the circulation system dynamics in three dimensions. This minimally invasive and non-contact approach is performed without the application of contrasting agents. The optical design achieved a resolution of 2.2 m over a distance of 800 m ...
      Read Full Article
    8. Non-contact investigation of the corneal biomechanics with air-puff swept source optical coherence tomography

      Non-contact investigation of the corneal biomechanics with air-puff swept source optical coherence tomography
      In this paper, we use swept source optical coherence tomography combined with air-puff module (air-puff SS-OCT) to investigate the properties of the cornea. During OCT measurement the cornea was stimulated by short, air pulse, and corneal response was recorded. In this preliminary study, the air-puff SS-OCT instrument was applied to measure behavior of the porcine corneas under varied, well-controlled intraocular pressure conditions. Additionally, the biomechanical response of the corneal tissue ...
      Read Full Article
    9. Method and apparatus for imaging of semi-transparent matter

      Method and apparatus for imaging of semi-transparent matter
      The invention relates to a method and apparatus for measuring the spatial and velocity distribution of scattering structures of a sample in semi-transparent matter. The acquired spectral data I(k, t) are transformed in two steps to image data I(z, v). A Doppler shift is imposed on the light to a separate real and mirror images in the v space to suppress the complex ambiguity artifact.
      Read Full Article
    10. Coherence properties of fast frequency swept lasers revealed via full electric field reconstruction

      Coherence properties of fast frequency swept lasers revealed via full electric field reconstruction
      A novel, time-resolved interferometric technique is presented allowing the reconstruction of the complex electric field output of a fast frequency swept laser in a single-shot measurement. The power of the technique is demonstrated by examining a short cavity swept source designed for optical coherence tomography applications, with a spectral bandwidth of 18 THz. This novel analysis of the complete electric field reveals the modal structure and modal evolution of the ...
      Read Full Article
    11. Imaging of the stroke-related changes in the vascular system of the mouse brain with the use of extended focus Optical Coherence Microscopy

      Imaging of the stroke-related changes in the vascular system of the mouse brain with the use of extended focus Optical Coherence Microscopy
      We used Optical Coherence Microscopy (OCM) to monitor structural and functional changes due to ischemic stroke in small animals brains in vivo. To obtain lateral resolution of 2.2 m over the range of 600 m we used extended focus configuration of OCM instrument involving Bessel beam. It provided access to detailed 3D information about the changes in brain vascular system up to the level of capillaries across I and ...
      Read Full Article
    12. Tissue thickness calculation in ocular optical coherence tomography

      Tissue thickness calculation in ocular optical coherence tomography
      Thickness measurements derived from optical coherence tomography (OCT) images of the eye are a fundamental clinical and research metric, since they provide valuable information regarding the eyes anatomical and physiological characteristics, and can assist in the diagnosis and monitoring of numerous ocular conditions. Despite the importance of these measurements, limited attention has been given to the methods used to estimate thickness in OCT images of the eye. Most current studies ...
      Read Full Article
    13. Optical Coherence Tomography of the Labial Salivary Glands Reveals Age-Related Differences in Women

      Optical Coherence Tomography of the Labial Salivary Glands Reveals Age-Related Differences in Women
      The labial minor salivary glands (LSGs) play a role in medical research and practice due to their superficial location and involvement in both systemic and localized diseases. Swept-source optical coherence tomography (OCT) is a noninvasive modality that enables in vivo , micrometer resolution, wide-field three-dimensional imaging in seconds. A purpose-built swept-source OCT instrument was employed to acquire three-dimensional datasets covering the area of 2.43 cm 2 of the mucosa of ...
      Read Full Article
    14. Differentiation of morphotic elements in human blood using optical coherence tomography and a microfluidic setup

      Differentiation of morphotic elements in human blood using optical coherence tomography and a microfluidic setup
      We demonstrate a novel optical method for the detection and differentiation between erythrocytes and leukocytes that uses amplitude and phase information provided by optical coherence tomography (OCT). Biological cells can introduce significant phase modulation with substantial scattering anisotropy and dominant forward-scattered light. Such physical properties may favor the use of a trans-illumination imaging technique. However, an epi-illumination mode may be more practical and robust in many applications. This study describes ...
      Read Full Article
    15. 1-15 of 108 1 2 3 4 5 6 7 8 »
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. About Maciej Wojtkowski

    Maciej Wojtkowski

    Maciej Wojtkowski (b.1975) received his MSc and PhD in physics from Nicholas Copernicus University (NCU), Torun, Poland. Presently he has a faculty position of research assistant professor in the Institute of Physics, NCU, Poland. His research interest includes optical coherence tomography and low coherence interferometry applied to biomedical imaging.
    He is active in the field of Optical Coherence Tomography (OCT) and its ophthalmic applications. Dr Wojtkowski has impact on development of Spectral OCT technique. The first SOCT instrument for in vivo retinal imaging was designed and constructed by dr Wojtkowski and his colleagues from the Medical Physics Group at Nicolaus Copernicus University Poland in 2001. Application of Spectral OCT to ophthalmology enabled group from Torun obtaining retinal cross-sectional images with the shortest exposure times and in turn it allowed proving speed and sensitivity advantage of Spectral OCT over standard OCT method. Dr Wojtkowski also contributed in development and construction of three clinical prototype high resolution SOCT instruments which are in use in ophthalmology clinics: in Collegium Medicum in Bydgoszcz, Poland, New England Eye Center, Boston, USA, and UPMC Pittsburgh.

  3. Quotes

    1. For our group at NCU it was more about having an industrial partner, which in the long term could give job opportunities for MSc and PhD students and PhDs from our group one of the conditions of our collaboration was creation by Optopol a R&D office at NCU.
      In Optical Coherence Tomography Used $500M of Federally Funded Research Over The Past Decade: How was it Used, What was Accomplished, and What’s to Come?