Hemiparesis as a result of a traumatic pseudoaneurysm of the carotid bifurcation

History and clinical findings: A 20-year-old patient was referred to our cl inic after sudden onset of a left-sided hemiparesis. His past history revea led a severe trauma 4 years ago, including multiple bone fractures, rupture of the spleen, as well as renal failure; and an acute respiratory distress syndrome, from which he showed good recovery, At that time no central-nerv ous symptoms could be found. However, eighteen months ago, he complained ab out a transient weakness of his left arm and leg. Investigations: Examination of the cerebral arteries by duplex-sonography s howed an aneurysm on the bifurcation of the right carotid artery with a per ipheral flow-reduction. This could be confirmed by CT- and MR-based angiogr aphy, which also revealed a reopened embolic occlusion of the M1-segment of the right middle cerebral artery. On CT and diffusion weighted imaging the re was evidence of an ischemic infarction pattern. Treatment and course: Under anticoagulation therapy with heparin the patien t showed complete recovery from his symptoms. Duplex-sonography as well as MR-angiography documented a complete reopening of the primarily occluded mi ddle cerebral artery. Finally, surgical reconstruction of the aneurysmatic part of the vessel was done. Conclusion: This case illustrates the potential risk of a traumatic aneurys m as a potential source of ischemic brain infarctions. We emphasize the imp ortance of imaging the cerebral arteries in traumatic patients, even in the absence of initial neurological symptom.