[Arteriovenous anastomosis in nasal cavities using microcorrosion technique].

In the present study the morphology of arteriovenous anastomoses in the nasal area are analyzed using the microcorrosion technique. This technique calls for perfusion of the vascular system, passing through the left ventricle, with Batson's of the vessels. For the first time in the microcorrosion study of the nasal vascular network human fetuses (from the 12th to 24th week of intrauterine life) obtained from spontaneous abortions were used as well as rats weighing from 250 to 300 gr. The animals were anesthetized with sodium thiopental prior to administration of the resin. A specimen containing the facial muscles, the nasal pyramid, the maxillary bone and the palatine bones was excised. Then, from this specimen the nasal septum and the two lateral portions of the nose were obtained. The bony and soft perivascular tissues were removed by placing the casts in an aqueous 20% KOH solution. Finally the corrosion cases were observed under a scanning electron microscope (EM). Within the nasal cavities the microcorrosion technique makes it possible to identify three different vascular layers: superficial, intermediate and deep. In the latter it proved possible to visualize the two types of arteriovenous anastomoses: i.e. simple and complex. On the basis of both vascular course and the impressions left by the endothelial cell nuclei it proved possible to differentiate between the arterial and venous portions of the anastomoses.