Abstract
In laser coagulation therapies, it is important to evaluate a coagulated layer and the depth precisely for preventing excessive laser irradiation. In this paper, we have developed the combination system of a coagulation laser and an optical coherence tomography (OCT). The continuous wave solid-state laser with a wavelength of 532 nm was used as a coagulation laser. The Swept laser with a center wavelength of 1.3μm was used in the swept-source OCT (SS-OCT) imaging system. The frame rate and axial resolution were 50 fps and 12μm, respectively. Real-time tomographic images of the coagulated layers of chicken tissues and liver tissues were obtained by this system. The attenuation coefficient was evaluated from the raster-scan signal of the reflection light intensity of the OCT image. The measured attenuation coefficient of the coagulated layer was much higher than that of the normal tissue. Furthermore, we demonstrated the automatic measurement of the attenuation coefficient by the LabVIEW program originally developed. As a result, the attenuation coefficients increase consistently with a progress of coagulation.
