| Abstract: | The choice of a procedure for measurements of blood vessels (b.v.) should depend on the type of b.v. investigated: For vessels defined anatomically and in respect to their function of organ supply the method of SUWA et al. (1961) is the most adequate one, provided that b.v. dilatations developing during lifetime and persisting after death as a result of special methods of fixation or shock-freezing or being generated by postmortal perfusion can be excluded. Changes in wall thickness of defined b.v. sectioned transversally can also be determined by measurement of the wall area and/or the maximal chord length. At undefined vessels procedures which measure the wall-to-lumen ratio are useless, because lumen changes are not quantifiable. Thus lumen changes can mask of mimick changes in wall thickness. The especially interesting b.v. either with a pathologically changed or without an elastic membrane are not measurable. The unsable method to detect changes in wall thickness at undefined b.v. is founded on the determination of the vessel wall area and/or the number of all the b.v. classified according to their diameter of a certain organ region. But the investigation of the smallest precapillary vessels presupposes their visualization by a special modification of the ATPase reaction. |
