[Contribution of intracranial "traumatic aneurysm" (author's transl)].

Three clinically and histologically verified cases of "traumatic aneurysm" concerning the a. basilaris, a. communicans posterior, and a. lenticulostriata have been used to demonstrate that these acute and subacute lesions do not belong to the true aneurysms, as defined pathologically and anatomically. They can be considered as acute traumatic lesions of arteries with periarterial hematoma (aneursyma spurium) and should be designated as pseudoaneurysms. Such pseudoaneurysms must not only be differentiated from true aneurysms by radiological and clinical findings but also by histological investigation. An intracranial artery rupture with formation of an pseudoaneurysm due to a blunt injury can also exist without a fracture of the base of the skull. Since traumatic lesions of the striatum arteries are caused especially in children and young adults, the localization of an acute hemorrhage in the basal ganglia does not exclude a traumatic etiology. Early closure of the injury in the artery wall and surroundings by fibrin and thrombotic material with following repairing processes are important for latency between injury and rupture of the pseudoaneurysm.