Materials hitherto used for wrapping intracranial aneurysms failed to prevent early and late recurrent hemorrhage. This is probably because the mechanical strength of these materials is insufficient to reinforce the aneurysmal wall. To obtain early as well as long term prevention of bleeding, we have been using a Dacron fabric to wrap the aneurysms. So far five aneurysms at various locations (three at the IC, two blister-like, non-ruptured and one fusiform, non-ruptured, one at the MCA bifurcation, non-ruptured, and one at the vertebral artery fusiform, ruptured) have been wrapped. Although the follow-up periods are short,-the longest one being two and a half years -the patients are all doing well with no hemorrhage. The Dacron fabric which has been commonly used in cardiovascular surgery is rather inelastic and the cut end does not come loose. So it was thought that this material would have sufficient toughness to reinforce the aneurysmal wall as long as it made contact with the wall or pressed against it after the wrapping was completed. But since the Dacron fabric is slightly hard and thick (0.5mm thick), there were some difficulties in manipulating it during the operative procedure. At the end of wrapping, the free ends of the Dacron fabric were approximated and closed with Sugita's clips. For this purpose “L” shaped clips with blades which open parallel to each other were used because other types of clips did not close at the tips due to the thickness of the Dacron fabric. Occasionally sutures or Weck's clips were required to close the Dacron fabric.
Arieti reported the first example of a patient harboring an aneurysm and an arteriovenous malformation (AVM). After his publication, numerous case reports and small series began to appear in the literature. But little attention has been focused on the clinical features and the most appropriate medical and surgical care of such patients. Therefore we report our 24 cases and discuss the therapeutic principle involved. Since 1961, 24 patients with this combination of lesions have been treated in our clinic. Fourteen cases are male, ten cases are female. Nineteen patients (79.2%) were examined after intracranial hemorrhage, and the remaining five because of seizures. The average age of the patients at first appearance of symptoms was 46.5 for the former group and 31.2 for the latter. Thirty-nine aneurysms were involved. There were 23 aneurysms around the circle of Willis (59.0%), and 16 (41.0%) on the feeding vessels. The ratio of the former group arising from the vertebro-basilar system is high and from the AC system is low compared with the common aneurysms. In angiograms, three aneurysms (7.7%) are not related to the AVMs hemodynamically. Our therapeutic principle is to treat both lesions by the same approach simultaneously. If this is impossible, we will treat the aneurysm first, because the rebleeding rate of ruptured AVM's is low (Graf CF 1983); on the other hand, aneurysms bleed easily especially when hemodynamic changes associated with the resection of the AVM occur (Nornes H 1980, Batjer H 1986). During the operation, it is recommended that the feeding artery be temporarily occluded under the administration of Sendai Cocktail. The results of the above treatment were good in 83.3% of the patients, fair in 12.5%, while 4.2% of the patients died.
Sixteen cases of cerebral aneurysms associated with intracranial arteriovenous malformations (AVMs) have been found in these hospitals. The mechanism of the development of these aneurysms in this combination of intracranial vascular lesions has been documented by many previous authors. However, less attention has been focused on the most appropriate surgical management of these patients. We report on 16 patients with both lesions (aneurysms and AVMs), and discuss the therapeutic problems of this type of lesion. The following are our conclusions: 1) We have treated 116 cases of AVMs, 16 of which (14%) were associated with cerebral aneurysms. The rate of this combination of intracranial vascular lesions is not small. Therefore, precise preoperative neuroradiological examinations should be made to confirm the presence or absence of aneurysms in all patients with cerebral AVMs. We must carefully consider whether the two lesions may be located separately, for example, one lesions exists supratentorially, and the other is located infratentorially. 2) Preoperative diagnosis of the source of hemorrhage is necessary to decide the priority of surgical procedure, especially when the lesions are located separately. The advent of CT (computerized tomographic) scanning has made it easier to detect the source of hemorrhage. However, it is often difficult to correctly locate the source in many patients at the chronic stage of hemorrhage, and in a few patients at the acute stage. 3) In patients hemorrhaging from whatever source, when aneurysms and AVMs are located close together, both lesions can be treated in a sigle operation. However, when they are located separately, the priority of surgical procedure should be directed to the source of hemorrhage. when the source is unclear, cerebral aneurysms should be clipped first. 4) From the present study, we were unable to conclude whether or not unruptured aneurysms associated with AVMs should be operated on.
Cerebral aneurysms associated with arteriovenous malformation (AVM) have often been reported with special reference to the hemodynamic effect of aneurysm formation. In this paper, we surveyed 15 cases with such combinations and discussed the etiologic aspects and suitable therapeutic plans. The mean age of our patients was older than that of patients with AVM's alone. This suggests that the duration of the hemodynamic effect was important in the formation of aneurysms associated with AVM's. Seventy-two percent of the aneurysms were located on the arteries hemodynamically related to the AVM. When the size of the nidus was larger, aneurysms tended to be located more peripherally on the feeding arteries close to the nidus. Though both AVM's and aneurysms cause hemorrhagic cerebrovascular diseases, their natural histories differ, especially in the rate and timing of rebleeding. It is important to determine which lesion is responsible for the bleeding. When there is subarachnoid hemorrhage (SAH) but no intracerebral (ICH) or intraventricular hemorrhage (IVH) are shown on the CT scan, the bleeding source will be a ruptured aneurysm. On the other hand, ICH or IVH with or without SAH is mainly due to AVM rupture. In treatment of cases where aneurysms are associated with an AVM, both lesions should be operated on simultaneously, and if this is impossible, the responsible lesion should be operated on first. In cases with aneurysm rupture, considering its high risk of rebleeding in the acute stage, the aneurysm should be clipped as soon as possible. Even if the aneurysm is not ruptured but is located on an artery where aneurysms usually develop, such aneurysms should also be operated on because of the high risk of bleeding.
During the past 17 years, we have experienced 173 cases of AVMs. Among these, 15 cases (8.7%) were associated with aneurysms. All aneurysms were located in typical proximal arteries such as main feeding arteries or the circle of Willis and were hemodynamically related to an AVM. There were seven cases of subarachnoid hemorrhage and one case of intraparenchymal hemorrhage. The remaining seven were examined because of unconsciousness, seizure and/or hemiparesis. Nine of the 15 patients underwent surgery. In one case the procedure was directed toward the aneurysm alone, in two cases toward the AVM and in six cases toward both lesions. Surgery should first concentrate on the ruptured lesion. However, in some cases it was hard to make preoperative diagnosis of the ruptured lesion. Also, it is desirable to treat the AVM and the aneurysm in one operation. We experienced a case where total excision of the AVM alone resulted in the disappearance of the aneurysms. Even in an unresectable AVM with a non-ruptured aneurysm, it is preferable to clip the aneurysm to prevent bleeding. In two cases with an unresectable AVM, a newly formed aneurysm was discovered in the follow-up angiogram, emphasizing that serious follow-up angiography is required for untreated AVMs.
Arteriovenous malformations (AVMs) associated with intracranial aneurysms are on uncommon condition. Twelve cases of AVMs associated with cerebral aneurysms were reported in a series of 180 AVMs (6.7%) over the last 17 years, six of these were in the posterior fossa. Most all showed a hemodynamic correlation between the AVM and the aneurysm. AVMs and aneurysms should be treated surgically in one operation, however if this is not possible, we should take care of the hemodynamic change induced by the operative procedure. In the case of aneurysm rupture or unknown origin of hemorrhage, the aneurysm should be treated prior to the AVM. With conservative therapy, we observed enlargement of the aneurysm size in one patient, however there was no incidence of rebleeding.
Twelve cases of intracranial aneurysm associated with cerebral arteriovenous malformation were found in a total of 130 cases of cerebral AVM (9.2%). Hemorrhages, including intracerebral hematoma, were found in 10 cases. The source of bleeding was presumed to be the AVM in five cases and the aneurysm in three cases. Convulsion occurred in two cases. The aneurysm was situated in the main feeding artery to the AVM in five cases, proximal to the origin of the main feeding artery in nine and unrelated to the AVM in two. These findings strongly indicate the importance of hemodynamic stress in aneurysm formation. Aneurysms and associated AVMs should both be treated surgically, preferably in one operative stage. The aneurysm should be treated first, if it is the source of hemorrhage. It should be treated first, if it lies proximally to the AVM, even if the source of hemorrhage is unclear or the source is the AVM. The AVM should be removed in advance of the aneurysm only when each lesion is situated in a different arterial region and the AVM is the source of hemorrhage.
We have experienced 11 cases of cerebral arteriovenous malformation (AVM) associated with an aneurysm or an arterio-venous varix(AVV). Five of the patients were male and six were female, and the mean age was 42. Eight cases were supratentorial, and three were infratentorial. Initial symptoms were bleeding in seven cases, seizure in one, and involuntary movement in one. Among the seven cases with bleeding as the initial symptom, bleeding occured from the aneurysm in three cases, and from the AVM in two cases; in two cases the source of bleeding was undetermined. A two-stage operation was performed in five cases of initial bleeding lesions. Surgical results were excellent in all but one case, in which neither the AVM nor the aneurysm was accessible. The etiology of these combinations of lesions could be explained by the hemodynamic theory. In high flow AVMs, the probability of formation of an aneurysm or the risk of rupture of the aneurysm should be considered during the follow-up period. And in such cases, to prevent rupture of the aneurysm, radical surgery of the AVM should be considered, taking into account the risk of postoperative neurological deficits.
We have experienced 83 cases of intracranial arteriovenous malformations(AVMs) during the last five years, from August, 1982 to August, 1987, and 11 cases(13.3%) were associated with cerebral aneurysms. Totally 17 aneurysms were associated with AVMs including four cases of multiple aneurysms. Tweleve aneurysms were located in typical proximal sites or in abnormal distal locations along the feeding system to the AVMs, and the other five were located in sites remote and apparently hemodynamically unrelated to the AVMs. Six patients(55%) presented subarachnoid hemorrhage, diagnosed by CT scans and operative findings; four patients bled from an aneurysm, one patient from the AVM, and in one patient the source of bleeding was unknown. CT scans could not detect the bleeding source in two patients. Surgical treatment was performed in eight cases. Four cases were treated for aneurysms only, and four cases were treated for the combination of lesions. One-stage operation was performed in three of the four cases and two-stage operation in one case. All aneurysms were treated before the resection of the combined AVMs to avoid aneurysmal bleeding caused by the hemodynamic changes associated with the abrupt removal of the AVMs. Our experience and that reported in the literature led us to decide that every patient with this combination of lesions should have the aneurysm treated first. Exceptions to this principle are cases of large intracerebral hematomas from AVMs, or patients with hemodynamically unrelated remote aneurysms.
Among 230 patients with vertebrobasilar aneurysms who were hospitalized in Chiba University Hospital and its affiliated hospitals, there were eight cases (3.5%) associated with arteriovenous malformation(AVM). Age: 40-63 years old (53.5±9.0 years). There were no patients in their 20's or 30's even in cases where the AVM was responsible for the bleeding. The age distribution seems to follow the natural history of aneurysms. Sex: Four males and four femdes. Responsible lesion: Intracranial hemorrhage occurred in seven cases and the responsible lesion was not determined in two cases. The AVM was responsible in four cases and the aneurysm in only one. Hemodynamic relation: Hemodynamic relation was considered angiographically in seven cases. Three aneurysms were located along the feeder to the AVM, two were at the origin of the feeder, and two were at the proximal artery to the feeder. Location of AVM: The AVM was located in a supratentorial space in four cases and in an infratentorial space in four cases. Treatment and outcome: Both lesions were surgically treated in five cases and all of the five patients made good recovery. Surgery was not performed in three cases; one of these patients recovered, one died, and one was not followed-up. Conclusion: The vertebrobasilar aneurysms associated with AVMs had very similar characteristics to those reported in the literature on anterior circulation aneurysms with AVMs.
Five cases of association of subtentorial cerebral aneurysms with AVMs were reported. The site of the aneurysm was bifurcation of the basilar artery in one case, the peripheral superior cerebellar artery in one case, and in three cases the site was the peripheral posterior inferior cerebellar aretry. All AVMs were located at the superior surface of the cerebellum. Subarachnoid hemorrhage was seen in four cases and the bleeding origin was always the aneurysm. Case 1, a 48-year-old-man, died before surgery. Both anerysm and AVM were treated simultaneously in three cases showing SAH, and their postoperative course were uneventful. In Case 5, a 43-year-old-man, only neck-clipping of a non-ruptured aneurysm and microvascular decompression of the right trigeminal nerve was performed. In the literature, there were 13 cases of such association, and in all of them the source of bleeding seemed to be the aneurysm, just as in our experience.
We have had six cases of moyamoya disease associated with aneurysms during the past 17 years. The incidence was 16%. In three cases, the aneurysms were located on moyamoya vassels or on the peripheral small arteries such as Heubner's artery, the posterior choroidal artery and the tentorial artery and were classified as a “pseudoaneurysm”. Two pseudo-aneurysms disappeared spontaneously within three months after onset. Therefore, pseudo-aneurysms required no direct surgery, though STA-MCA anastomosis had a preventative effect on rebleeding. Conversely, the remaining three cases were classified as saccular aneurysms, located on the circle of Willis such as the carotid fork, anterior communicating artery or basilar bifurcation. Of these three cases, only one, the basilar bifurcation aneurysm, rebled two years later, causing death due to vasospasm, while the other two aneurysms, on the carotid artery system, did not rebleed and showed gradual reduction in size. Based on our experience, it was suggested that aneurysms on the vertebrobasilar system should have direct surgery because of a high probability of rupture, whereas aneurysms on the carotid artery system, showing better prognosis, can be treated conservatively with careful follow-up angiography.
The authors reviewed five cases of Moyamoya disease associated with intracranial aneurysms, among 60 cases of Moyamoya disease experienced during the past 17 years. The initial symptom was hemorrhagic ictus in all cases. CT scans revealed subarachnoid homerrhage in two cases and intracerebral hemorrhage in three cases. Angiography showed an aneurysm at the basilar tip in one case, at the C2 portion in three cases and at the distal portion of the anterior choroidal artery in one case. In regard to treatment, we operated two patients in the early stage, treated two patients conservatively and planned a delayed operation for aneurysmal clipping on one case. In the last case, the patient expired from rerupture of the aneurysm prior to the operation. The following points are important in the surgical treatment of Moyamoya disease with intracranial aneurysms manifesting intracranial hemorrhage. 1) In case of rupture of an aneurysm located on the circle of Willis, a clipping operation should be performed to prevent rerupture. 2) In case of a peripheral aneurysm, follow-up angiography is necessary. When the aneurysm disappears, a reconstructive operation should be performed to prevent rebleeding from the Moyamoya vessels.
In this paper, we report on two cases of intracranial cerebral aneurysms and one case of cerebral arterial ectasia with moyamoya vessels. A 43-year-old female experienced one episode of TIA. Angiograms showed elongated, ectatic vessels on the right internal cerebral artery, the left posterior cerebral artery and the right subclavian artry, which were diagnosed as arterial ectasia. The cerebral arterial ectasia on the right internal cerebral artery was accompanied with moyamoya vessels. Wrapping of the ectatic vessel and STA-MCA anastomosis was performed. A 68-year-old female suffered from intracerebral hematoma in the right temporal lobe. Cerebral angiograms showed the typical appearance of Moyamoya disease. An aneurysm was identified on the left internal carotid artery. During the frontotemporal approach, the aneurysm was found unruptured and was clipped. The moyamoya vessels were few in this case and the operative procedures were easily performed. A 54-year-old female suddenly suffered from headache and vomiting, falling into coma soon after. Moyamoya vessels were noticed on the left carotid angiogram. A vertebral angiogram showed an aneurysm on the top of the basilar artery. Because her conscious level gradually improved after ventricular drainage, a direct approach to the aneurysm was planned. Under hypotensive anesthesia, clipping of the aneurysm was performed with the retraction of the right internal carotid artery medially or laterally. She did not fully awaken from the anesthesia, and remarkable brain swelling was noticed on the postoperative CT scan. She died on the 14th postoperative day. There are several problems in performing a direct attack on cerebral aneurysms with moyamoya vessels. The first is whether there are many or few moyamoya vessels. If there are many moyamoya vessels, a direct approach to the aneurysmal neck might be prohibited, especially with a basilar aneurysm. The second problem is that intraoperative hypotension and excessive retraction of the major vessels might be dangerous, because severe disturbance of the cerebral perfusion could occur in moyamoya disease if such procedures are followed.
Eleven patients with occlusive intra- and extra-cranial lesions in the same cerebrovascular system (tandem lesions) were treated by a combination of carotid endarterectomy(CEA) and extraintracranial bypass(EC/IC bypass). In this paper, we report on the therapeutic principles involved with these patients and a newly developed external shunt system used during CEA for preservation of blood flow in the external carotid artery when this procedure was preceded by an EC/IC bypass. The eleven parients were divided into three groups based on the findings of preoperative cerebral angiography: Group A with a primary lesion in the cervical carotid artery(5 patients), Group B with intra- and extra-cranial lesions of similar degrees (3 patients), and Group C with a primary lesion in the intracranial cerebral artery (3 patients). The CEA preceded the EC/IC bypass in Groups A and B, but the EC/IC bypass was performed first in Group C. Three patients in Group A were subclassified as Group A′ because of specific carotid lesions. In Group A′, one patient with an occlusive cervical carotid lesion extending to the inferior margin of C1 underwent an EC/IC bypass before the CEA, but the other two, with an occlusive lesion in the cervical internal carotid artery and narrowing of the external carotid artery, initially underwent a CEA of the external carotid artery. During the CEA in the four parients in whom the EC/IC bypass was performed first, the external shunt system we developed was used along with the conventional internal shunt system to preserve the blood flow in the external as well as internal artery system. Good surgical results were obtained, and the postoperative courses were favorable.
In this paper, the authors discuss which side should be first operated on in patients with “Moyamoya” disease with bilateral hemispheric symptoms. Fifty-nine patients (33.7%) out of 175 cases with “Moyamoya” disease were found, on the first examination to have bilateral hemispheric ischemic symptoms (including TIA and RIND). These patients underwent bilateral surgical revascularization according to the following policy: (1) In principle the dominant (left) hemisphere should be operated on first. (2) In the following cases the non-dominant (right) hemisphere should be operated on first: (a) When there is little likelihood of the neurological recovery of the left hemisphere. (b) The right hemispheric symptoms are worse or more progressive than the left. (c) Others All 35 patients who underwent operation first on the left hemispher and 23 out of 24 patients who underwent operation first on the right hemisphere have improved in ADL compaired with the preoperative state. There was only one patient whose left hemispheric symptoms at the second (left side) operation had become worse than at the first (right side) operation. The policy seems to be proper.
During aneurysm surgery, regional cortical blood flow (CoBF) was continuously monitored in six patients with a thermal diffusion flow probe in an attempt to assess the effects of temporary major artery occlusion on flow. The equipment and methods employed are presented in this paper. The CoBF was stable between 50 to 70ml/100g/min. Changes in flow due to vascular occlusion were readily apparent. The reduction in flow was milder in common and internal carotid occlusion than in the obliteration of the middle (M1) and anterior (A1) cerebral artery. The occlusion time varied from 0.5 to 14 minutes and CoBF decreased to 15 to 50ml/100g/mim. Five patients showed no postoperative deficits. Their CoBF and occlusion time were as follows: 15ml/100g/min for one minute, 25ml/100g/min for eight minutes and 50ml/100g/min for 14 minutes. One patient revealed bilateral basal ganglia infarction after occlusion of the dominant left A1 segment for six to eight minutes, which was not detected by CoBF monitoring. Attention should be paid to the blood flow in the deep structures when a temporary clip is applied at the site proximal to perforating branches. Direct measurement of CoBF may be of value in estimating the length of time that temporary clipping of a major vessel can be tolerated.
Three cases of azygos anterior cerebral artery associated with an aneurysm, a case of persistent primitive trigeminal artery associated with three aneurysms, a case of persistent primitive hypoglossal artery associated with an aneurysm and a case of persistent primitive trigeminal artery associated with moyamoya disease are reported in this paper. We show the high incidence of associated vascular malformations with these abnormal vessels and consider the main etiological factors in the aneurysmal formation to be the hemodynamic change and the developmental defect in these arteries.