A lateral shearing interferometer was used to examine the smoothness of the tear film. The information about the distribution and stability of the precorneal tear film is carried out by the wavefront reflected from the surface of tears and coded in interference fringes. Smooth and regular fringes indicate a smooth tear film surface. On corneae after laser in situ keratomileusis (LASIK) or radial keratotomy (RK) surgery, the interference fringes are seldom regular. The fringes are bent on bright lines, which are interpreted as tear film breakups. The high-intensity pattern seems to appear in similar location on the corneal surface after refractive surgery. Our purpose was to extract information about the pattern existing under the interference fringes and calculate its shape reproducibility over time and following eye blinks. A low-pass filter was applied and correlation coefficient was calculated to compare a selected fragment of the template image to each of the following frames in the recorded sequence. High values of the correlation coefficient suggest that irregularities of the corneal epithelium might influence tear film instability and that tear film breakup may be associated with local irregularities of the corneal topography created after the LASIK and RK surgeries.
The aim of our work was to determine a therapeutic effect of photodynamic therapy (PDT). Twenty five patients with the
Bowen's disease, actinic keratosis and basal cell carcinoma (superficial, nodular) were examined. They were treated with
photosensitizer - aminolevulinic acid (metabolized in protoporphyrin IX), and the new red light source built of high-power
diodes. A new method, based on numerical analysis of fluorescence imaging of tissues, was proposed as a way for
controlling therapy.
In cancer diagnostics the most important problems are the early identification and estimation of the tumor growth and
spread in order to determine the area to be operated. The aim of the work was to design of statistical algorithms helping
doctors to objectively estimate pathologically changed areas and to assess the disease advancement. In the research,
algorithms for classifying endoscopic autofluorescence images of larynx and intestine were used. The results show that
the statistical pattern recognition offers new possibilities for endoscopic diagnostics and can be of a tremendous help in
assessing the area of the pathological changes.
The purpose of this study is to investigate the kinetics of precorneal tear film stabilization process after eye blink and the process of creating the break-up of the tear film layer. The tear film of patients were examined in vivo by used the lateral shearing interferometer. The information about the distribution and stability of the tear film over the cornea is carried by the wave front reflected from the surface of tears and coded in interference fringes. Smooth and regular fringes indicate the smooth surface of tears over the cornea. Immediately after eye blink the interference fringes are observed on background of bright and dark areas. The contrast of this structure fades with time slowly and after 1-3 sec the background of interference fringes becomes uniform. The vertical orientation and instability of this structure suggests connection with eyelid movement and the spread of tears. If the eye is kept open for a long time, bright lines appear in the background of fringes after a dozen seconds. The slowly appearing structure might signify the tear film break-up. In case of eyes after a LASIK surgery the shape of the background structure has different nature and might be stable in time suggesting the stability of the corneal surface irregularities.
The research presents the design and construction of a diffuser made of plastic fiber. The diffuser enables us to convey
laser energy to the coronary vessels and allows their biostimulation. The project is a continuation of research on cellular
biostimulation carried out at the Institute of Telecommunication, Teleinformatics and Acoustics, and Wroclaw Medical
University Department of Cardiology.
The paper presents a digital analysis of autofluorescence endoscope images in real time. The numerical analysis allows us to define with close approximation the area of cancerously changed tissue in real time.
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