Imaging Cylindrical Micro-Structures

For cross-sectional images the tubes were sectioned into thin segments of approximately 1 mm thickness cut perpendicular to the tube’s long axis. The images of the tube’s walls were obtained after sectioning along the tube’s long axis. The samples were placed in glass bottom 35 mm-dishes (MatTek Corporation, P35G-1.5-14-C) filled with milliΩ water. The samples were then imaged in between two perpendicular light polarizers using a Leica DM750 P instrument in reflection mode with a ×4 magnification using Leica Application Suite V4.2 software. A sample stage allowed for the precise rotation and x, y-positioning of the samples. Cross-sectional images were stitched using the ImageJ plugin tools “MosaicJ” and Grid/Collection Stitching by Preibisch et al^{41 (link)}. Bright-field images were recorded using the same instrument without the light polarizers.