Quantitative distinction between scar and physiologic dermis in guinea pig skin using laser light scattering from histological tissue sections. Representative scattering patterns for dermis and scar can be analyzed to compute the orientation index, S, which varies from 0 (perfectly random alignment) to 1 (perfect alignment). Top: Histologic views from the reticular region of normal dermis (left) and from scar (right). Bottom left: Laser scattering patterns from dermis, showing S = 0.20 ± 0.11, indicative of a largely random orientation pattern with a small component of alignment (in the epidermal plane). Bottom right: Scar shows S = 0.75 ± 0.10, indicating high, but not perfect, orientation. (Adapted from (30)).