Rapid and efficient characterization of cervical collagen orientation using linearly polarized colposcopic images

Abstract

Collagen provides tissue strength and structural integrity. Quantification of the orientated dispersion of collagen fibers is an important factor when studying the mechanical properties of the cervix. In this study, for the first time, a new method for rapid characterization of the collagen fiber orientations of the cervix using linearly polarized light colposcopy is presented. A total of 24 colposcopic images were captured using a cross-polarized imaging system with white LED light sources. In the preprocessing stage, the Red channel of the RGB image was chosen, which contains no information of the blood vessels because of the low-absorption of blood cells in the red region. OrientationJ, which is an ImageJ plug-in, was used to estimate the local orientation of the collagen fibers. The result shows that in the nonpregnant cervix, the middle zone (Zone 2) has circumferentially aligned collagen fibers while the inner zone (Zone 1) has randomly arranged. The collagen fiber dispersion in Zone 2 is much smaller than that in Zone 1 at all four quadrants region (anterior, posterior, left, and right quadrant). This new analysis technique could potentially combine with diagnostic tools to provide a quantitative platform of collagen fibers in the clinic.

Keywords

• Cervix
• collagen fibers
• collagen orientation
• coherency
• cross-polarized imaging
• colposcopy