This lecture will explain underlying concepts of OCT with a discussion of cutting-edge technological developments. In spectral-domain OCT, the reference mirror position is fixed and the mixed interference patterns are separated via spectral wavelength analysis. OCT uses low-coherence interferometry to produce a two-dimensional image of optical scattering from internal tissue microstructures in a way that is analogous. The combination of the digital optics and digital cockpit offered by the Artevo 800 allows surgeons and theatre staff to view a three-dimensional image of the ophthalmic procedures on a 55 4K monitor while simultaneously accessing real-time data, including optical coherence tomography (OCT) images, on the screen. In time-domain OCT, the reference mirror position is altered, so that interference patterns are generated whenever the two beams have traveled almost the same amount of time. Broadband (i.e., low “coherence”) light sources are used, because they produce a wider band of wavelengths, and thereby enable greater sensitivity in comparing the travel time differences of the two beams. Incident light is thus split into two beams, and the beam backscattered from the ocular tissue is then compared (“interfered”) with the beam that has traveled a known time from the reference mirror. The axial resolution of 6m and lateral resolution of 18m have been realized. An achievable scanning speed of 29.2k line/sec has been reached and it can acquire 3-dimensional data sets in 9 second. 1 It measures depth-resolved reflections of near-infrared light to create cross-sectional images of tissue with micrometer resolution. By scanning the line field electronically at the SLM, volumetric OCT imaging can be performed without mechanical scanning. Since it is extremely difficult to directly detect the shorter “echo” times it takes light to travel from different structures at axial distances within the eye, interferometry is used. A high speed spectral domain optical coherence tomography (SDOCT) system was demonstrated. Based on the principle of low coherence interferometry, OCT is a relatively recent imaging modality that was proposed in the early 1990s. The much higher speed of light compared with sound allows for finer cross-sectional views of the retina and anterior segment. Optical Coherence Tomography (OCT) is an optical analogue to ultrasound imaging.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |