In order to study tissue structure, i.e. the size and shape of cells, we use confocal laser scanning microscopy (CLSM). Samples for CSLM may be minimally prepared. Our methodology most often involves cutting fresh slices of tissue with a vibratome, short staining and immediate imaging under the microscope to obtain 2D images. In a single image, for a typical cell size, we have anything from several to hundreds of cells. This opens the possibility of analyzing any number of images using the same protocol. Such objective, fast and efficient methodology combined with random, uniform and isotropic sampling ensures the robust characterization of tissue structure, which may be correlated with macroscopic properties.