| Popis: |
These dysembryogenetic malformations, also called medullary angiomas, are dilations or anomalies of the arterial, venous or capillary vascular compartment. We distinguish: the raceme-venous angioma (exclusively of venous nature), formed by bluish pial vein conglomerates, sinuous, not pulsating, containing venous blood, and sometimes an ample more or less tortuous vein; and the arteriovenous angioma, formed by arteries and veins communicating between them through a tangle of abnormal vessels, without capillary interposition. This angioma appears as a turgid group of pulsating arteria vessels, containing high pressure arterial blood and by ample, tortuous, venous vessels, pulsating as well; the arterial angioma, purely arterial, is very rare in the spinal cord; the cavernous angiomas or cavernomas are tumor-like malformations of small dimensions, without intervascular tissue, often they are surrounded by coagulated venous blood; the telangectasias are dilations of capillary vessels separated by normal tissue. They can have cavernomatous aspect due to progressive dilation of the vasal walls and secondary disappearance of intervascular tissue. |
