Fig. 4

(a) Representative histological section stained with Sirius Red. (b) Post-processed histological section of perineal specimens at 20x magnification. Blue and green tones represent fibers oriented in the horizontal direction, while red tones represent fibers oriented in the vertical direction. (c) Polar histogram of the collagen fibers. Radial distance represents fiber density, while the angle, in degrees, indicates fiber orientation. Shaded bars show the distribution of fiber densities across directions.