Polarimetric Accessory for Colposcope

Available for licensing and commercial development is a colposcope accessory device that compensates and resolves tissue borne specular reflections. In medical diagnostic procedures for examining the cervix and the tissues of the vagina and vulva, long working-distance (-30 cm) lighted binocular microscope (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. The present polarimetric accessory overcomes this limitation and enhances the visibility of subsurface structures of the scattering object. Linearly polarized light is used for cervical illumination and imaging is performed through an additional polarizer that separates the specularly reflected light from the diffusely backscattered light, which originates in deeper tissue layers, allowing 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 to be 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 have been developed. Though the diffusely backscattered light presents only a small fraction of the detected light, its analysis, using the customized design and image processing procedures, provides useful information about internal structures of biological tissues. The polarimetric accessory includes a linear polarizer for the illuminating beam, two beam splitters for preserving polarization state, lens system for imaging, polarization analyzer, band-pass optical filter, digital camera, and electronic triggering system.

Potential Commercial Applications: Competitive Advantages:
  • Gynecological examinations
  • Image quality
  • Resolution of tissue structures at close microscopic distances

Development Stage:


Amir Gandjbakhche (NICHD)  ➽ more inventions...

Victor Chernomordik (NICHD)  ➽ more inventions...

Moinuddin Hassan (NICHD)  ➽ more inventions...

Alexander Sviridov (NICHD)  ➽ more inventions...

Zachary Alissi (NICHD)  ➽ more inventions...

Paul Smith (NIBIB)  ➽ more inventions...

Albert Boccara (NICHD)  ➽ more inventions...

Intellectual Property:
U.S. Pat: 9,801,536 issued 2017-10-31
US Application No. 61/620,295
US Application No. 14/390,354

Jacques SL, et al. PMID 10685085
Jacques SL, et al. PMID 12175282
Ramella-Roman JC, et al. PMID 15568952
Sviridov AP, et al. “Analysis of Biological Tissue Textures Using Measurements of Backscattered Polarized Light” (presented at the Optical Society of America - Biomedical Optics Topical Meeting, Fort Lauderdale, Florida, March 2006). PMID 17212522
Sviridov AP, et al.

Licensing Contact:
Heather Gunas,
Email: gunash@mail.nih.gov
Phone: 240-276-5530

OTT Reference No: E-084-2012-0
Updated: May 10, 2018