[Calcinosis of the carotid siphon--morphology, differential diagnosis and clinical relevance].

In order to determine the clinical significance and hemodynamic relevance of carotid siphon calcification 241 patients were investigated by doppler sonography and skull x-ray. Comparing 139 patients with and 60 patients without siphon calcification, we examined the predictive value of carotid calcification regarding obstructive vessel disease as indicated by doppler sonography. Both groups were compared with 42 patients who all had doppler sonographic signs of severe carotid stenosis. No significant difference was found regarding the incidence of stenosis between the groups with and without siphon calcification (13% vs. 15%). Interpreting siphon calcification as a general sign of atherosclerosis seems therefore not justified. An over proportionally high rate (61.9%) of siphon calcification can only be expected by selected patients with severe obstructive vessels disease. Etiological factors are discussed and differential diagnosis of siphon calcification is demonstrated by cases.