[Spontaneous angiographical disappearance of an unruptured giant aneurysm of the basilar top demonstrated by a sequential series of angiograms. A case report].

One of the case of the angiographically disappeared giant aneurysm is reported, which was arising from the top of the basilar artery. A 52-year-old man was admitted in April, 1978. He had developed a recent memory disturbance, tremor in the both upper extremities, the rigidity of the four extremities, an ataxic gait and urinary incontinence. Enhanced CT scan on admission demonstrated a large oval mass in the suprasellar region indenting nearly total third ventricle. Bilateral lateral ventricles were significantly dilated. The initial vertebral angiogram shortly after the admission revealed an oval-shaped aneurysm, 27 mm in the longest diameter, arising from the top of the basilar artery. The aneurysm was considered to be inaccessible due to its anatomical location and size. A ventriculoperitoneal shunt was placed, which alleviated clinical symptoms and signs immediately. However, a vertebral angiogram 1 year following the initial angiogram showed significant enlargement of the aneurysm, in spite of hypotensive and coagulant drugs which had been administered, then the administration of hypotensive drugs was ceased. Ventriculo-peritoneal shunt was replaced by ventriculo-atrial shunt in Sep. 1980. Left vertebral angiogram in May, 1981, 3 years after the initial angiogram, demonstrated the aneurysm had completely disappeared. He has been followed-up by the repetitive angiography up to the present, which proved the aneurysm has not reappeared. The occurrence of a spontaneous angiographical disappearance of an intracranial aneurysm is relatively uncommon, especially of a giant aneurysm. A rare case of spontaneous angiographical disappearance of a giant aneurysm was presented in this report.(ABSTRACT TRUNCATED AT 250 WORDS)