Spontaneous thrombosis of an intracranial giant aneurysm.

SUMMARY: Spontaneous thrombosis in giant aneurysms is known, whereas complete occlusion of such aneurysms in a short period of time is rarely reported. We present the case of a 50-year-old man with a giant anuersym arising from the anterior communicating artery (ACA) producing significant mass effect with clinical consequences. The digital subtraction arteriogram (DSA) showed a patent lumen of about 20 mm and a very small neck leading to extremely slow blood flow inside the sac and stagnation of contrast. During catheterization for endovascular occlusion four weeks later, the arteriogram revealed complete disappearance of the aneurysm, while the patient remained clinically stable. The patient was operated upon and the thrombosed sac was removed with no complications. He was discharged one week later and recovered completely from his symptoms within three months.