Polarimetric Accessory for Colposcope

In medical diagnostic procedures for examining the cervix and the tissues of the vagina and vulva, long working-distance (-30 cm) lighted binocular microscopes (colposcope) that provide up to 25x optical magnification are used to create an illuminated magnified view. Speculum dilations can give rise to specular reflections from the tissue surface, causing physicians to overlook possible abnormalities – thus decreasing the quality of a colposcopy. Researchers at the National Institute of Child Health and Human Development (NICHD) developed a polarimetric accessory that overcomes this limitation and enhances the visibility of subsurface structures of the scattering object. Linearly polarized light is used for cervical illumination and imaging performed through an additional polarizer that separates the specularly reflected light from the diffusely backscattered light originating in deeper tissue layers. This technology provides enhanced imaging of the hidden subsurface tissue structure (texture). The region of interest is illuminated by linearly polarized light, and backscattered light passes through the polarization filter that is detected by a digital camera. A custom optical design preserves the polarization state of the backscattered light in the microscope, without interfering with the standard optical path and operation of the microscope – including its binocular system. Special algorithms to visualize regions of statistical similarity in the image were developed. T...
Source: NIH OTT Licensing Opportunities - Category: Research Authors: Source Type: research