MICROVASCULAR PATTERNS OF THE HUMAN LARGE INTESTINE: MORPHOMETRIC STUDIES OF VASCULAR PARAMETERS IN CORROSION CASTS

The microvascularization of 19 human colonic segments was studied quantitatively by means of scanning electron microscopy of microvascular corrosion casts. In total, four caecums, two ascending and four descending colons, six sigmoidal colons and four rectums were examined. In order to describe quantitatively the microvascular unit, three parameters were assessed: (1) intercapillary distances, (2) interbranching distances and (3) branching angles. All parameters were measured in stereo pairs of microvascular corrosion casts using an interactive image analyzing system. Examination of microvascular corrosion casts showed the mucosal capillary network arranged in a honeycomb pattern around the mucosal glands. This meshwork is supplied by arterioles and subepithelial capillaries and drained by venules which merge to submucosal veins. The average value for the intercapillary distances is 107.2 ± 27.6 µm, for the interbranching distances 51.3 ± 28.5 µm and for the branching angles 87.4 ± 29.2°. Comparisons of the quantified parameters within a given segment as well as group comparisons of all segments did not reveal any significant inter-individual difference.