A SMALL-ANGLE LIGHT-SCATTERING DEVICE FOR PLANAR CONNECTIVE-TISSUE MICROSTRUCTURAL ANALYSIS

The planar fibrous connective tissues of the body are composed of a de nse extracellular network of collagen and elas tin fibers embedded in a ground matrix, and thus can be thought of as biocomposites. Thus, th e quantification of fiber architecture is an important step in develop ing an understanding of the mechanics of planar tissues in health and disease. We have used small angle light scattering (SALS) to map the g ross fiber orientation of several soft membrane connective tissues. Ho wever, the device and analysis methods used in these studies required extensive manual intervention and were unsuitable for large-scale fibe r architectural mapping studies. We have developed an improved SALS de vice that allows for rapid data acquisition, automated high spatial re solution specimen positioning, and new analysis methods suitable for l arge-scale mapping studies. Extensive validation experiments revealed that the SALS device can accurately measure fiber orientation for up t o a tissue thickness of at least 500 mu m to an angular resolution of similar to 1 degrees and a spatial resolution of +/-254 mu m. To demon strate the new device's capabilities, structural measurements from por cine aortic valve leaflets are presented. Results indicate that the ne w SALS device provides an accurate method for rapid quantification of the gross fiber structure of planar connective tissues.