title: [The morphology of arteriovenous anastomoses in congenital angiodysplasias].
abstract: Congenital angiodysplasias are frequently accompanied by arteriovenous shunts. Large direct shunts between arteries and veins may determine the destiny of the affected limb. They are easily detectable by clinical methods. Small multiple anastomoses, however, may necessitate special investigation methods (circulatory tests) for detection. A hemodynamic influence of multiple small shunts has not yet been proved, but it is well known that they are the cause of intraoperative hemorrhages and of local recurrences of hemangiomas in spite of apparently radical removal. Small arteriovenous anastomoses are not easily detected by routine histology methods. Even in series sections they may be difficult to identify, because the blood vessels in angiodysplasias are poorly differentiated and the small shunts are well hidden in cavernous hemangiomas. Various types of arteriovenous shunts may occur in congenital angiodysplasias. Small shunts were found in all the examined cases, even when they had not been detected clinically by special circulatory tests.
mesh_terms: D000328:Adult; D001163:Arteriovenous Anastomosis / Q000473:pathology*; D001808:Blood Vessels / Q000002:abnormalities*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male
vernacular_title: Zur Morphologie der arteriovenösen Anastomosen bei kongenitalen Angiodysplasien.