Intracranial aneurysms generally produce neurological deficit by means of hemorrhage, vasospasm or mass effect. Aneurysms as a suspected source of emboli have rarely been reported in the literature. On the other hand, the operative management of large and giant aneurysms is complicated by their atheromatous and thick walls, frequent intramural thrombosis with calcification, and broad-based necks. We describe a case of a 63-year-old woman in whom a partially thrombosed large aneurysm of the right middle cerebral artery (MCA) was the source of emboli resulting in transient ischemic attacks (TIAs). In this report, the usefulness of endaneurysmal microendarterectomy for direct obliteration of the large aneurysm with a hard, calcified atheroma at its base is particularly emphasized.
A 63-year-old woman was admitted with a history of several episodes of left arm weakness that cleared within 5 minutes. A neurological examination showed unstableness in one leg standing, but no other abnormalities. Physical examination and routine laboratory data were normal. A CT scan revealed a large high-density mass in the right sylvian fissure. A MRI demonstrated a 2-cm right sylvian mass indicative of a partially thrombosed large aneurysm. Right carotid angiography showed a 7 mm aneurysm at the bifurcation of the MCA and occlusion of the prerolandic artery. There were no other abnormal angiographic findings.
A right frontotemporal craniotomy was performed. The right carotid cistern was opened and the proximal internal carotid artery was obtained. The right sylvian fissure was subsequently dissected and opened. Proximal and distal control of the MCA and its branches was obtained. The neck and base of the aneurysm were then circumferentially exposed. A calcified atheroma at the aneurysm base prevented clip placement without compromise of the parent artery. Once the temporary clips were in place, the dome of the aneurysm was transected. Intramural thrombectomy was performed with an ultrasonic aspirator. By grasping the thickened aneurysm wall, a cleavage plane between the atheroma and the aneurysm wall with a microdissector was developed. Thereafter, endaneurysmal microendarterectomy was completed. Removal of the atheroma allowed complete obliteration of the aneurysm neck with Sugita clips (#15 and #18). Local circulation was restored after 22 minutes of occlusion. The patient had an uneventful postoperative course and suffered no further TIAs.
Temporary trapping of the aneurysm, intramural thrombectomy, and endaneurysmal microendarterectomy allow direct obliteration of the aneurysm neck with preservation of the parent artery.

抄録全体を表示

Surgical results in 90 cases with occlusive lesions in the vertebral arteries are summarized. Several surgical procedures were done: vertebral artery (VA) endarterectomy in 11 patients, VA transposition in 26, saphenous vein bypass graft in 22, extravascular decompression of the VA in 12 and percutaneous transluminal angioplasty (PTA) in 19.
The choice of the operative maneuver depends on the location of the lesion. For stenotic lesions in the V1 segment of the VA, PTA is indicated first. For those refractory to PTA, VA transposition is indicated.
For occlusion of the V1 and or V2 segment of the VA, saphenous vein bypass graft is indicated.

抄録全体を表示

We performed 79 carotid endarterectomies in 72 patients in the last 7 years. This report describes surgical results, complications and follow-up in those endarterectomies. We used internal shunts under barbiturate brain protection in all cases. The mean time for shunt insertion and removal is 3 minutes and 4.5 minutes, respectively. We used surgical microscope and removed plaques as a whole block. The surgical mortality was 2.8% (2 cases) and major morbidity was 2.8% (2 cases). The cause of operative death in two cases was rupture of the suture, which resulted in blood loss and subsequent fatal infarction. One case of major infarction was caused by temporary occlusion of the carotid artery. The bilateral vertebral arteries of this case were occluded, and collaterals were from the carotid artery through the stenotic part. The other case of major infarction was caused by inappropriate collection of the intimal flap and inappropriate usage of the large-sized internal shunt. The follow-up disclosed only one case of infarction occurred in the surgical side, because the patient failed to take anti-platelet drugs. Two cases developed symptomatic restenosis of the endarterectomy site because of myointimal hyperplasia. Complication of endarterectomy can be avoided by careful intra- and postoperative care.

抄録全体を表示

We performed seven carotid endarterectomies (CEA) associated with ischemic heart disease. We classified the operative procedure into three groups according to symptoms: 1) CEA prior to A-C bypass (simultaneous operation), 2) Percutaneous transluminal coronary angioplasty (PTCA) prior to CEA, and 3) Separated operations. Group one comprised three cases, group two had one, and group three had three. CEAs were performed under administration of barbiturate with intraarterial shunt. There was no mortality or morbidity.
CEA was recommended for patients with previous neurological symptoms and appropriate bifurcation disease and for patients with asymptomatic carotid bruit caused by significant stenosis of the proximal ICA. Prophylactic CEA for the patient with an asymptomatic carotid bruit is controversial. On the other hand, neurological complications might be expected to occur in high frequency among patients with recognized carotid stenosis at the time of myocardial revascularization. Whether carotid and coronary arterial revascularization should be performed simultaneously or separately remains a controversial question. In asymptomatic patients, cerebral hypoperfusion in extra-corporeal circulation at the A-C bypass is a danger, and carotid vascular reconstruction must be performed before A-C bypass. In symptomatic patients, CEA without myocardial revascularization may be dangerous in impending anginal attack.
Our operative strategies are as follows: simultaneous CEA and myocardial revascularization are desirable for both symptomatic and asymptomatic carotid lesions. PTCA is suitable for coronary high-risk patients in the face of myocardial infarction intraoperatively. In separate onset of stroke, there are no problems for treatment of each disease.

抄録全体を表示

A 38 year-old-female presented with subarachnoid hemorrhage due to rupture of the left internal carotid artery-posterior communicating artery (IC-PC) aneurysm. The aneurysm was clipped on the day of onset. Postoperative carotid angiography (CAG) revealed an infundibular dilatation (ID) at the origin of the right posterior communicating artery. Therefore follow-up of the ID was carried out by right CAG after 3.5 years, and a development of the ID into a saccular aneurysm was verified. This newly developed right IC-PC aneurysm was clipped by the second operation. About 7 years after the first operation, she experienced transient ischemic attacks of left internal carotid artery twice in a short period. Therefore a third left CAG was performed, and development of a previously overlooked small aneurysm of the internal carotid bifurcation into a saccular one was detected. The third aneurysm was clipped by the third operation. She has been well throughout her clinical course.
She was specific in whom two aneurysms developed newly after the operation of a ruptured aneurysm, and these two aneurysms were operated on successfully prior to an occurrence of bleeding from the newly developed aneurysms.
In this paper, the genesis and growth of cerebral aneurysm are discussed. We emphasize the necessities of detailed analysis of the initial angiogram and of follow-up of a small aneurysm and pre-aneurysmal lesion including ID by angiography.

抄録全体を表示

Twenty-four carotid endarterectomies (CEA) were performed in 22 cases of internal carotid (IC) stenosis. Nine had bilateral stenosis and 2 underwent CEA on both sides. Preoperative angiography showed other intracranial vascular lesions in 67% of the bilateral cases, and in 38% of the unilateral cases. Neurological signs in bilateral cases were major stroke in 3 patients (33%) and minor stroke in 6 patients (67%). On the other hand, minor stroke had occurred in only 8 patients (62%) and TIA was presented in 3 (33%) patients with unilateral lesion. Complete occlusion developed on one side in 2 of the bilateral stenosis 4 months after contralateral CEA. These facts suggested that arteriosclerotic change is severe and advanced in bilateral stenosis. And, when bilateral IC stenosis is found to be over 50% or with ulcer in the case of ischemic neurological deficits, bilateral CEA is recommended before complete occlusion.
Good cross flow was demonstrated preoperatively in 46% of unilateral IC stenosis, but in bilateral cases only 11% had good cross flow, and 44% of them showed poor cross flow. EEG changes such as attenuation of background activity and slow waves following IC clamp were observed in 50% of bilateral stenosis and 20% of unilateral stenosis. During endarterectomy with operating microscope, an IC clamp is necessary to continue for about 60 min and an internal shunt is indicated to prevent hypoperfusion in every case, especially when associated with bilateral stenosis. CEA should be performed in the dominant side first, because this operation is for prophylaxis of further ischemic attack.

抄録全体を表示

We performed frontal encephalo-myo-arterio-synangiosis (EMAS) combined with encephalo-duro-arterio-synangiosis (EDAS) in children with moyamoya disease. Only EDAS was done in the parietal region on 17 sides in 13 cases, and frontal EMAS with EDAS was performed in the parietal region on 16 sides in 11 cases. Collateral formation was confirmed on the postoperative external carotid angiograms and improvement of clinical symptoms were examined. Frontal EMAS with EDAS was better than EDAS only in terms of the development of collateral circulation and postoperative clinical improvement. Frontal EMAS may be recommended for an additional surgical procedure of EDAS on children with moyamoya disease.

抄録全体を表示

Twenty patients underwent endovascular treatment for cerebral arteriovenous malformation (AVM). In the initial ten patients, preoperative occlusion of feeding arteries was performed using detachable balloon catheter. In the next ten patients, embolizations of nidus of the AVM were performed using liquid ethylene vinyl alcohol co-polymer or polyvinyl alcohol particles through Tracker-18 catheter or leak balloon catheter. We compared the effects and problems between preoperative balloon occlusion of feeding arteries and embolization of nidus.
Both balloon occlusion and embolization were performed after provocative test. There was no complication associated with balloon occlusion, but there were five minor neurological deficits among twenty-one procedures of embolization. Though the balloon occlusions were efficient, some of them were not so effective because of the incomplete flow reduction of balloon occlusion. In one case the AVM disappeared completely only by embolization. In another case, after embolization, the AVM was treated by bragg-peak proton-beam therapy, a form of stereotactic radiosurgery.
In conclusion, preoperative balloon occlusion is relatively safe and this method is effective in some cases. However, it is incomplete in some other cases. On the other hand, embolization is more effective for the treatment of the AVM, and this method might be used as not only preoperative treatment but also final treatment in combination with stereotactic radiosurgery. And it should be performed very carefully in order not to cause any complications.

抄録全体を表示

Surgical results were analyzed in 17 cases of unruptured aneurysms associated with ischemic cerebrovascular disease (CVD). The age of patients ranged from 26 to 76 and the mean age of the patients was 61. The associated ischemic CVD were minor completed stroke in seven, RIND in four, TIA in four and vertebrobasilar insufficiency (VBI) in two cases. Twenty-two aneurysms were verified in 17 cases and 19 aneurysms were treated surgically. Of the 19 aneurysms, nine were located in the middle cerebral artery (MCA), five in the internal carotid artery (ICA), four in the anterior communicating artery (A coin A) and one in the anterior cerebral artery (ACA). CT scan showed small low density areas in eight cases. Bilateral ICA stenosis was found in one, MCA stenosis in one and MCA occlusion in one cases on the preoperative angiography. Sixteen aneurysms were successfully clipped and three had aneurysmal coating. Superficial temporal artery (STA)-MCA anastomosis was also performed at the same stage of aneurysmal operation in one case with MCA occlusion. Neurological symptoms worsened or developed after operation in five cases. Possible causes of neurological aggravation were cerebral contusion due to excessive brain retraction in two and low cerebral perfusion pressure during operation in three cases. These results indicated the importance of careful and gentle manipulation of ischemic brain and maintenance of adequate cerebral perfusion during operation.

抄録全体を表示

This study is based on eighty-five cases of unruptured asymptomatic aneurysms associated with ischemic cerebrovascular disease. Sixty-one cases (73 aneurysms) were treated surgically and 24 cases were treated non-surgically. The post-operative course was uneventful in 50 out of 61 cases (82%) and unsatisfactory in 11 cases (18%). There was no significant relation of the surgical results to site of aneurysm, type of stroke, or pre-operative CT and angiographical findings. The results appeared to correlate with patients' age and surgical technique. In the 11 unsatisfactory cases, symptoms worsened due to an intracerebral hematoma (ICH), an enlargement of the infarcted area or a subarachnoid hemorrhage (SAH). The cause of death in five cases, three of which were patients over 70, was attributed to acute myocardial infarction in 2 cases, large post-operative ICH in 2 cases and SAH in 1 case.
In the 24 cases without surgery, only one aneurysm ruptured during 1-7 years follow-up.
Based on these results, surgery might be indicated for cases with complicated lesions to prevent future SAH due to rupture of aneurysm and stroke following TIA. However, surgery is associated with a high rate of post-operative complications, because ischemic brain tissue is very vulnerable to retraction pressure. Patients over 70 with these complicated lesions should be excluded from surgical indication.

抄録全体を表示

Superselective embolization of cerebral AVMs is performed to facilitate surgical removal or to attain complete obliteration primarily. Various embolic materials are used for embolization. However, their effectiveness and facility of use varies. We compared three embolic materials: silk threads, Avitene powder and Ethibloc. 16 AVMs were embolized. Silk threads did not obliterate the nidus satisfactorily. Avitene powder was effective for preoperative embolization but not for obliteration by staged embolization because of recanalization. Ethibloc proved useful for staged embolization, due to less recanalization and was much easier to deal with.

抄録全体を表示

The authors describe the efficacy and safety of carotid ligation designed especially for surgical treatment of a giant aneurysm of the internal carotid artery (ICA) in clinical and experimental studies. To determine the safety of ICA ligation, the balloon Matas test was administered for the ipsilateral ICA in nine patients with ICA aneurysms, seven of whom had giant aneurysms. Neither ischemic symptoms nor EEG changes developed during testing of the giant ICA aneurysms. Further, angiograms demonstrated that the contrast material filled poorly into the intracranial arteries distal to the aneurysm. In four of the seven giant aneurysms. ICA ligation effected good results with no complications.
Using five models of an experimental giant aneurysm made of a canine descending aortic segment, the intra-arterial pressures of the common carotid artery was measured at the proximal and distal portions of the aneurysm with the transcatheter technique. Significant reductions of the arterial blood pressure and pulse pressure at the distal portion of the giant aneurysm model were noted.
The data suggest that reductions of the mean pressure and pulse pressure in the distal ICA of the giant ICA aneurysm promote the development of collateral circulation. Thus, in many cases of giant aneurysm, ICA ligation would tend to preclude hemodynamic ischemia. When the neck of a giant aneurysm is difficult to clip, carotid ligation may be a safe alternative surgical treatment that yields good results.

抄録全体を表示

The potential benefits and indications for thromboendarterectomy for total occlusion of neck internal carotid artery causing acute neurologic deficits are still controversial. This report discusses the results of thromboendarterectomy for acute internal carotid artery occlusion in 7 patients, performed within 10 days after the first signs of neurological deterioration.
The patients were categorized in two groups depending on preoperative clinical symptoms and angiographic findings: 3 patients with mild stroke and good collateral flow and 4 patients with profound stroke and poor collateral flow. On preoperative CT scan, three patients including one of the minor stroke group already had a small infarction located in the border/terminal zone of middle cerebral artery. It was possible to restore the blood flow in 6 patients, but postoperative reocclusion occurred in one. The postoperative courses contrasted sharply in the two groups. In all three patients of mild stroke group, preoperative symptoms disappeared or improved after surgery. On the other hand, the results of 4 patients with profound stroke were extremely poor, including two postoperative deaths.
The results of this study and others reported in the literature indicate that careful case selection is mandatory in thromboendarterectomy for acute internal carotid artery occlusion. It is our present policy to operate positively on patients with progressing minor stroke and good collateral flow, but not to operate on patients with acute stroke and poor collateral flow.

抄録全体を表示