[Spontaneous thrombosis of an azygos anterior cerebral artery aneurysm--report of a case (author's transl)].

A case of spontaneous thrombosis of azygos anterior cerebral artery aneurysm was reported. A 39-year-old man was admitted to our hospital on April 23, 1979, 5 days following an apparent attack of subarachnoid hemorrhage. On admission, he complained a headache and left hemiparesthesia. Neurologic examination revealed a very slight nuchal rigidity, left hemihypesthesia and hypalgesia. Routine laboratory studies were noncontributory. Left and right carotid angiograms showed an azygos anterior cerebral artery aneurysm. Twelve days after the attack, a left carotid angiogram demonstrated a segmental narrowing and widening of an azygos anterior cerebral artery, and then the aneurysm was filled incompletely. Nineteen days after the attack, the aneurysm was not visualized on right carotid angiogram. Neck clipping and resection of the aneurysm was performed on May 8, 1979. Cross section of the aneurysm exposed a thrombus. He showed postoperatively a slight hypesthesia in the left lower limb. Complete thrombosis of intracranial aneurysm occurring spontaneously is rare. We collected 42 such cases including the present case from the literature and discussed some factors facilitating intraluminal thrombosis. Although the shortest previous period of thrombosis is noted to be over a course of 5 days, the thrombosis in our case in 19 days after subarachnoid hemorrhage was certainly a relative rapid event.