[Surgery of anterior communicating artery aneurysms with the perforating artery branching from the dome].
The authors have treated two cases of anterior communicating artery aneurysms with the perforating artery branching from the top of the dome. Case 1 was a 32-year-old female. She developed sudden-onset of headache while sleeping. Angiography showed an anterior communicating artery aneurysm with its dome directed upward. The left pterional approach was utilized, and a rather thick perforating artery was found branching from the top of the dome and going upward. Neck clipping of the aneurysm was performed resulting in interruption of the blood flow of the perforating artery. The patient showed no neurological deficit postoperatively. Case 2 was a 67-year-old female. She suffered from sudden-onset of headache and was transferred from another hospital to the author's care. Three-dimensional CT angiography revealed an anterior communicating artery aneurysm with its dome directed in the anterior-superior direction. A rather thick perforating artery was coming off the top of the dome. Neck clipping was carried out, but permanent memory impairment appeared postoperatively. The perforating arteries coming off the anterior communicating artery have been called the hypothalamic arteries. In 1994, Serizawa et al divided these arteries into three groups. One is the subcallosal artery, which gives blood flow not only to the hypothalamus but also to the subcallosal area. The other two are the hypothalamic and chiasmatic arteries. The authors consider that this nomenclature of those arteries is suitable in practical use for surgery, because these arteries have different vessel sizes, they originate from the anterior communicating artery, and supply different territories with blood. Since the septal nuclei are in the subcallosal area, interruption of blood flow of the subcallosal artery by the clipping of an aneurysm may result in memory impairment caused by damage to the septal nuclei. Serizawa et al also reported that some branches are coming from the A2-segment to the subcallosal area as collateral circulation. In the author's two cases, the perforating arteries branching from the top of the domes were considered to be subcallosal arteries, because their size was rather thick and the arteries were going upward directed probably to the subcallosal area. Memory impairment in case 2 was considered a natural outcome due to the interruption of blood flow of the subcallosal artery by the clipping of the aneurysm. On the other hand, in case 1, sufficient collateral blood flow from A2 to the subcallosal area might have prevented damage to the septal nuclei, probably because of the insufficient size of the subcallosal artery. In these rare cases, dome clipping and coating should be the first choice of treatment, because prognosis after dome clipping of the aneurysm with coating was rather satisfactory.
Matsuoka
Y
Y
Department of Neurosurgery, Izumi Municipal Hospital, 4-10-10 Fuchu-cho, Izumi, Osaka 594-0071, Japan.
Nagata
Y
Y
Honda
Y
Y
D000328:Adult; D000368:Aged; D002536:Cerebral Arteries / Q000473:pathology*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications / Q000601:surgery*; D008569:Memory Disorders / Q000209:etiology*; D011183:Postoperative Complications / Q000209:etiology*; D014656:Vascular Surgical Procedures / Q000379:methods