Large kissing aneurysms of the middle cerebral artery: a case report--classification of kissing aneurysms

We report a rare case of kissing aneurysms located at the middle cerebral artery. A 69-year-old man had a severe subarachnoid hemorrhage associated with intracerebral hematoma (Hunt and Hess grade 5, WFNS grade V). Angiography revealed two large-sized aneurysms of the middle cerebral artery, and these aneurysms were seen as contacting each other. Both aneurysms were adherent, with fibrous tissue at each dome site. Neck clipping was performed. The difficulty of neck clipping with kissing aneurysms is dependent upon the relationship between the two aneurysmal necks. We classify kissing aneurysms into two groups based on the location of the aneurysmal neck (Type 1: each aneurysmal neck is located on the same parent artery. Type 2: each aneurysmal neck is located on different parent arteries.). In Type 1, preoperative diagnosis of kissing aneurysms is difficult and premature rupture during the application of a clip occurs frequently. Therefore, careful and meticulous dissection between the aneurysms is especially required. On the other hand, with Type 2 cases, large aneurysms (> 15 mm) are seen much more frequently than in cases of Type 1. Our classification of kissing aneurysms is useful to assess the difficulty of neck clipping for these aneurysms.     

Evaluation of relation among aneurysmal neck, parent artery, and daughter arteries in middle cerebral artery aneurysms, by three-dimensional digital subtraction angiography

Intracranial aneurysms usually occur at arterial bifurcations. However, in middle cerebral artery (MCA) aneurysms, we often find that the aneurysmal neck does not necessarily exist just on the arterial bifurcation. In this study, we have evaluated the relation among aneurysmal neck, parent artery, and daughter arteries in middle cerebral artery aneurysms, by three-dimensional digital subtraction angiography. Twenty consecutive patients (9 men and 11 women) with MCA aneurysms were examined. The total number of aneurysms was 22, of which 10 aneurysms were unruptured and 12 were ruptured. Aneurysmal sizes and angles between the parent artery and each of the two daughter arteries were measured. Furthermore, aneurysms were classified into two types based on neck location. Thus, when the neck was located on the extension of the midline of the parent artery, it was defined as a classical neck type aneurysm, and when it was not, it was defined as a deviating neck type aneurysm. There were 15 cases of deviating and 7 cases of classical neck type. Interestingly, in the deviating neck type, all the aneurysms existed on the side of the daughter arteries of which the angles between parent arteries were narrower, and in 93%, the sizes of the daughter arteries in which the neck existed were smaller compared with other daughter arteries.     

Surgical treatment of distal anterior cerebral artery aneurysms (author's transl)

Forty-five patients with aneurysms of the anterior cerebral artery distal to the anterior communicating artery were operated on by a direct approach method in the years 1960-1973. The incidence of aneurysms in this location was 4.8% of the total 1,000 aneurysms. It is of upmost importance in the treatment of aneurysms to insure the parent artery for the purpose of temporary occlusion. This makes it easier and safer to approach the aneurysmal neck and to handle possible premature aneurysmal rupture. From this technical standpoint, the aneurysms in this location were classified into two types, ascending and horizontal. Aneurysms of the pericallosal artery between the origin of the anterior communicating artery and the knee of the corpus callosum were designated as the aneurysms of the ascending portion, whereas the aneurysms of the pericallosal artery from the knee of the corpus callosum and beyond were designated as the aneurysms of the horizontal portion. Depending on the location of the aneurysm, craniotomy was performed at one of two different sites. For aneurysms of the ascending portion, bifrontal craniotomy was determined and applied as the safest approach. A small parasagittal craniotomy was determined to be sufficient for aneurysms of the horizontal portion. Although the total operative mortality was 4 of 45 cases (9.0%), no mortalities nor morbidities occurred in the last 12 cases since 1972, when the sites of craniotomies were differenciated.     

Recurrent cerebral aneurysm suggestive of misplaced clipping. Case report

A case of recurrent cerebral aneurysm after complete neck clipping is described. A 47-year-old male who presented with headache and nausea underwent neck clipping of a berry aneurysm of the left middle cerebral artery. Ten days later, angiographic findings suggested the presence of a second, large aneurysm adjacent to the first, which suggested misplaced clipping. Reoperation confirmed that a new aneurysm had formed next to the original aneurysm. A possible explanation of the recurrence is as follows. The M1 flowed into the M2 at a right angle. The aneurysmal neck was situated on the distal end of the M1 and the dome protruded antero-inferiorly at an angle of nearly 90 degrees to the long axis of the M1 opposite the origin of the M2. The parent artery bulged slightly, and its wall was thin and reddish, just distal to the aneurysmal neck. Proximal to the neck there was another small bulge, but the wall here was normal. These bulges were coated with Oxycel and Biobond at the time of aneurysmal neck clipping. After clipping, blood flow into the dome was interrupted, and the consequent hemodynamic stress caused the bulges to expand dramatically and form a new aneurysm. The authors conclude that there is a likelihood of early recurrence after neck clipping if the parent artery exhibits such morphological features as observed in this case.     

Treatment of peripheral aneurysms of the posterior circulation

Peripherally located aneurysms of the posterior circulation are extremely rare. The outcome of patients with peripherally located aneurysms has been poor, and the treatment of such aneurysms has been surgically challenging. We report a consecutive series of peripherally located ruptured aneurysms in the posterior circulation, and discuss in this article the optimal treatment strategy for such lesions. Clinical presentation, neuroradiological findings, treatment method, and the outcome were reviewed retrospectively. Two cases with distal posterior cerebral artery aneurysm, two with distal posterior inferior cerebellar artery aneurysm, two with anterior inferior cerebellar aneurysm, and one with superior cerebellar artery aneurysm were included in this study (mean age, 59.3 +/- 16.0, M:F = 1:6). Three patients with good neurological status on admission who underwent clipping of the aneurysmal neck via craniotomy showed a favorable outcome. In contrast, four patients with poor neurological status on admission who underwent endovascular proximal occlusion of the parent artery showed an unfavorable outcome. Although the outcome of patients who underwent endovascular surgery was poor, endovascular proximal occlusion was effective in preventing re-rupture of the aneurysms. Proximal occlusion of the parent artery has several shortcomings such as cerebral infarction, but proximal occlusion at the very distal area of the parent arteries would not be critical because of good collateral circulation. Thus, endovascular proximal occlusion may provide us another option in the treatment of peripherally located aneurysms especially in patients with poor neurological status. Further data is needed to discover the optimal treatment for patients with peripherally located cerebral aneurysms.     

Craniotomy side for neck clipping of the anterior communicating aneurysm via the pterional approach

The safety and reliability of neck clipping of the anterior communicating artery (Acom) aneurysm via the pterional approach was evaluated in terms of craniotomy side in 39 consecutive cases operated on by the senior surgeon from April 1991 through March 2000. These aneurysms were approached in principle via the side where the proximal A2 portion of the anterior cerebral artery was located posteriorly, for the purpose of easier identification of all five arteries involved, i.e., A1 and A2 portions of the anterior cerebral arteries of both sides and Acom. All aneurysms were clipped safely irrespective of the approach side because it was possible prior to aneurysmal dissection to prepare both A1 portions of the anterior cerebral arteries for temporary clipping, but not as far as the place where the aneurysm projects inferiorly and its fundus adheres firmly to the optic chiasm. The security of perforating arteries, however, could not be confirmed even after the completion of neck clipping in 9 cases. Clipping was impossible in the other 2 cases. In 2 of these 11 aneurysms the difficulty in clipping was not based on what side was used for craniotomy but on their large size. In the remaining 9 aneurysms, the necks of which were all situated on the posterior wall of the Acom, the craniotomy side turned out to be inappropriate when they were approached via the side where the proximal A2 portion of the anterior cerebral artery was located posteriorly. It was concluded that the craniotomy side should be selected so that the surgeon can observe directly the neck of the aneurysm.     

大脑中动脉巨大型动脉瘤的手术治疗

目的 探讨大脑中动脉巨大型动脉瘤的手术治疗方法.方法 回顾性分析2001年1月至2008年3月17例颅内大脑中动脉巨大型动脉瘤患者的手术方法和疗效.术前采用CT、CTA、MR、MRA、DSA及三维DSA检查,以了解动脉瘤的部位、大小,形状以及侧支代偿情况,制定个体化治疗方案.在手术入路上多采用改良翼点入路,其中行动脉瘤瘤颈直接或塑形夹闭者4例,动脉瘤孤立或孤立后切除4例,动脉瘤切除或孤立后血管重建7例,动脉瘤包裹2例.结果 CT和MRI能清楚地显示动脉瘤的形状、大小.DSA及三维DSA能显示瘤颈以及与附近血管和骨质的关系.根据格拉斯骨预后评分表评分,出院时恢复优良者12例,中度病残4例,重度病残1例,无死亡病例.结论 术前有必要进行详细的影像学检查,有助于术者规划手术方法,制定个体化治疗方案,采用不同术式取得良好预后.载瘤动脉暂时性阻断、动脉瘤切开血栓清除均有助于瘤颈夹闭.血管重建技术为大脑中动脉巨大型动脉瘤的手术治疗开辟了新途径,明显改善了手术效果.     

Rupture mechanism of a thrombosed slow-growing giant aneurysm of the vertebral artery--case report

A 76-year-old male developed left hemiparesis in July 1991. The diagnosis was thrombosed giant vertebral artery aneurysm. He showed progressive symptoms and signs of brainstem compression, but refused surgery and was followed up without treatment. He died of rupture of the aneurysm and underwent autopsy in March 1995. Histological examination of the aneurysm revealed fresh clot in the aneurysmal lumen, old thrombus surrounding the aneurysmal lumen, and more recent hemorrhage between the old thrombus and the inner aneurysmal wall. The most important histological feature was the many clefts containing fresh blood clots in the old thrombus near the wall of the distal neck. These clefts were not lined with endothelial cells, and seemed to connect the lumen of the parent artery with the most peripheral fresh hemorrhage. However, the diameter of each of these clefts is apparently not large enough to transmit the blood pressure of the parent artery. Simple dissection of the aneurysmal wall by blood flow in the lumen through many clefts in the old thrombus of the distal neck may be involved in the growth and rupture of thrombosed giant aneurysms of the vertebral artery.     

Giant aneurysm of the azygos anterior cerebral artery--case report

A 77-year-old female presented with a giant aneurysm of the azygos anterior cerebral artery (ACA) manifesting as acute onset of akinetic mutism caused by enlargement of the aneurysm resulting from rapid thrombus formation within the aneurysmal sac. Thrombus removal to obtain decompression of the aneurysmal bulk and tension was performed before parent artery occlusion to prevent thromboembolic events. The aneurysmal neck was completely clipped with preservation of the parent artery and all branches. This strategy for direct neck clipping of a giant thrombosed distal ACA aneurysm can reduce the possibility of ischemic sequelae.     

Embolization of cerebral aneurysms with a liquid embolus,EVAL mixture: Report of three cases

Summary Embolization of three surgically difficult cerebral aneurysms was performed using our newly developed non-adhesive embolic material, EVAL mixture (ethylene vinyl alcohol copolymer). Conventional embolic materials such as detachable balloons or microcoils were not used because of a large or irregular aneurysmal neck. After temporary occlusion of the parent artery with a superselective balloon catheter, the EVAL mixture was slowly injected through a microcatheter placed in the aneurysm or parent artery. The locations of the aneurysms were anterior communicating artery, basilar artery-posterior cerebral artery and basilar artery-anterior inferior cerebellar artery (BA-AICA). One aneurysmal occlusion and 2 parent artery occlusions were performed. Patients had no persistent deficits. The patient with the BA-AICA aneurysm associated with an arteriovenous malformation died of rupture of the residual AVM due to haemodynamic change 2 weeks after embolization. In selected and limited cases, embolization of surgically difficult cerebral aneurysms using EVAL mixture was more effective and safer than embolization using conventional embolic materials such as balloons and microcoils.     

Aneurysms of the proximal anterior cerebral artery

The authors report eight cases of aneurysm of the anterior cerebral artery proximal to the anterior communicating artery (A1 segment). In six of these cases, the aneurysms arose from the proximal anterior cerebral artery at the origin of either a cortical branch (on case), the accessory middle cerebral artery (one case), or a perforating branch (four cases). In another case the aneurysm arose at the proximal end of the fenestration, whereas in the one remaining case no branch was present at the site of the aneurysmal neck.     

套塞法侧方单一纵切口隆颏术

目的:探求一种更简便、可靠的隆颏手术新方法。方法:对86例求术者行套塞法侧方单一纵切口隆颏术。在前庭沟唇侧设计一纵切口,横向定位于假体中外1/3位置,骨膜下剥离,假体套塞于骨膜下,粘膜肌层一次缝合。结果:2例于术后出现假体切口端上移,再次手术矫正后满意。随访68例均效果良好,切口Ⅰ期愈合。结论:该术式保持了颏部肌肉的完整性,操作简单,假体稳定性好,创伤小,恢复快。     

Coexistence of multiple metastatic brain tumors from thyroid carcinoma and cerebral aneurysms

A 73-year-old woman was admitted with coexistence of multiple metastatic brain tumor and cerebral aneurysm. She has been operated on for a tumor of the thyroid gland 3 years before. Computed tomography (CT) scan revealed well-defined, homogeneously enhanced masses in the left frontal and right posterior temporal region. Right carotid angiography showed a tumor stain supplied by the branch of the fronto-polar artery. Left carotid angiography showed an aneurysm at the anterior communicating artery and a tumor stain supplied by the posterior temporal artery. Total removal of the bilateral tumor and aneurysmal neck clipping were performed simultaneously with bi-frontal craniotomy and right temporal craniotomy in April of 1988. Histology of tumor was papillary carcinoma. The surgical indication and treatment for patients with coexistence of multiple brain tumor and cerebral aneurysm were discussed.     

Valve replacement in infective endocarditis with mycotic cerebral aneurysm. Report of a case with successful operation

A 49 year-old woman was hospitalized with headache and left-sided weakness. Computed tomographic scan and carotid angiogram revealed mycotic aneurysms of the bilateral middle cerebral artery with intracranial bleeding. Although all blood cultures were sterile, her physical examination suspected mitral regurgitation due to infective endocarditis and mycotic cerebral aneurysms. Severe congestive heart failure developed immediately after successful clipping for ruptured mycotic aneurysm of the right middle cerebral artery and then mitral valve replacement with prosthetic valve was performed 3 months after craniotomy. At operation, infective endocarditis on the mitral valve was confirmed. Her postoperative course was uneventful and the second craniotomy for aneurysm of the left middle cerebral artery has been planning.     

Rapid growth and rupture of a newly originated aneurysm near the clipped middle cerebral artery aneurysm

A 38-year-old man was admitted to our hospital because of severe headache following reduced level of consciousness on February 13, 1979. He was lethargic and showed neck stiffness. A lumbar puncture revealed bloody cerebrospinal fluid. Left carotid angiography showed a berry aneurysm of 11 mm in diameter at the bifurcation of the middle cerebral artery (MCA). Rebleeding occurred on February 21, and he fell into semicoma. But, his consciousness recovered to lethargy on the next day. On February 26, a direct intracranial operation was performed and a Sugita clip was placed to the aneurysmal neck. The postoperative course was uneventful. But, left carotid angiography on 8th day after operation showed a newly originated aneurysm proximal to the operated aneurysm. On the 12th postoperative day, he suddenly fell into coma. CT showed subarachnoid blood in the basal cisterns and intraparenchymal hematoma in the left temporal lobe. On the same day, left carotid angiography was performed and it showed the enlarged aneurysm. He died on the 19th day after operation. Autopsy was not performed. Three factors have been considered dealing with the recurrence of the operated aneurysm in the previous reports: first, local fragility of the vascular wall due to the clip edge. Secondly, macro- or microscopic residual aneurysmal neck, thirdly, broken or slipped clip. Our case had the following characteristics from the angiographical and operative findings: the orifice of the operated aneurysm was situated on the superior side of the parent artery and the aneurysm protruded posterosuperiorly at an angle of approximately 90 degrees to the long axis of M1.(ABSTRACT TRUNCATED AT 250 WORDS)     

Characteristics and surgery of aneurysms of the proximal (A1) segment of the anterior cerebral artery

AIM: Proximal anterior cerebral artery (A1) aneurysms are considered to be rare or even unique. Proper surgical planning around A1 segment is particularly essential in order to avoid injury of tiny perforating arteries. METHODS: In 17 patients with angiographically or intraoperatively diagnosed A1 aneurysms, representing 0.8% of 2 124 aneurysm patients treated surgically at our institution between 1991 and 2003, clinical presentation, neuroradiological findings, surgical treatment methods and outcome were retrospectively analyzed. RESULTS: Sixteen patients presented with subarachnoid hemorrhage; A1 aneurysms were ruptured in 13 cases. Five patients (29%) had multiple aneurysms. In all cases A1 aneurysms were saccular and their maximum diameter ranged from 4 to 25 mm, average, 7.2 mm; in 4 cases they projected from the origin of the perforating artery, in 6 at the bifurcation of the internal carotid artery, in 5 at the anterior communicating artery and in 2 from the convexity of the parent artery. In 15 patients aneurysms were clipped via ipsilateral pterional approach and in the remaining 2, including a case with a second middle cerebral artery aneurysm, through contralateral approach. Eleven patients had excellent outcome, three good, and three died. CONCLUSIONS: Angiograms must be thoroughly analyzed to correctly assess origin of the aneurysmal neck, and to plan the operative procedure as radiological presentations of distal or proximal A1 lesions resemble those of anterior communicating artery and internal carotid artery bifurcation aneurysms, respectively. Contralateral approach may facilitate surgical elimination of selected A1 aneurysms or enable one-stage clipping in patients with multiple bilateral aneurysms.     

Antegrade recanalization of a completely embolized vertebral artery after endovascular treatment of a ruptured intracranial dissecting aneurysm. Report of two cases

Occlusion of the parent artery is a traditional method of treatment of unclippable cerebral aneurysms. Surgical or endovascular occlusion of the parent artery proximal to the aneurysm has been recommended for the treatment of dissecting aneurysms located in the vertebrobasilar circulation. Nevertheless, occlusion of the parent artery may not result in permanent exclusion of the aneurysm from the systemic circulation because, occasionally, postoperative rebleeding occurs after proximal occlusion. Alternatively, endovascular occlusion of the affected site, including the aneurysmal dilation, and parent artery, is a safe and reliable treatment for dissecting aneurysms. The authors present two rare cases of ruptured vertebral artery (VA) dissecting aneurysms that were treated by endovascular occlusion of the affected site including the aneurysm and parent artery by using Guglielmi detachable coils. In both cases the VA recanalized in an antegrade fashion during the follow-up period. Based on these unique cases, the authors suggest that a careful angiographic follow up of dissecting aneurysms is required, even in patients successfully treated with endovascular occlusion of the affected artery and aneurysm.     

Surgical treatment of the carotid-ophthalmic aneurysms (author's transl)]

Six cases of carotid-ophthalmic aneurysm submitted to direct operation were studied. 1. One out of six cases died postoperatively (mortality rate 16.7%). 2. Exposure of the internal carotid artery at the neck is absolutely necessary for its temporary occlusion. Temporary occlusion of the internal carotid artery at the neck makes the dissection of the aneurysmal neck easier and prevents the aneurysmal rupture during operation. 3. To cope with various complicated handlings, bifrontal carniotomy is recommended. 4. In order to make easy the dissection of the aneurysmal neck, the unroofing of the optic canal as well as the extensive removal of the tip of the anterior clinoid should be performed. 5. From our experience as well as review of the literature, the surgical result of the giant aneurysms is bad. Some new therapy is expected to be developed for the giant aneurysm of this site.     

Two cases of azygos anterior cerebral artery aneurysm (author's transl)]

Two cases with azygos anterior cerebral artery were reported from an analysis of 37 cases of distal anterior cerebral artery aneurysm. Case 1 was a 57-year-old woman. She had an attack of subarachnoid hemorrhage two months before admission to our clinic. The anterior cerebral artery was not demonstrated on the right carotid angiogram, and an azygos anterior cerebral artery was visualized on the left carotid angiogram. The aneurysm was situated at the distal end of the azygos artery. Case 2 was a 71-year-old hypertensive woman. Subarachnoid hemorrhage occurred 6 days before admission to our clinic. The left carotid angiography with contraleteral compression revealed an azygos artery and an aneurysm in its middle part. The azygos arteries in both cases were confirmed at operation and aneurysmal necks were managed without any serious deficit. The distal anterior cerebral artery aneurysm is frequently accompanied by azygos artery. This vascular anomaly may cause a hemodynamic change and may be one of the factors of aneurysmal formation at this part.     

The combination of STA-MCA anastomosis with another operation for the occlusive cerebrovascular disease (author's transl)

Case 1. A 65 year old male had left hemiparesis with sudden onset since 8 years ago, which gradually aggravated for these 2 years. On Sept. 27, 1973, he was admitted to the Department of Neurosurgery, Kitano Hospital. There was left spastic hemiparesis with hemisensory disturbance and he could not walk without help for the maked spasticity. Left carotid angiogram revealed the complete occlusion of the internal carotid artery and marked stenosis of the external carotid artery at the common carotid bifurcation. External carotid endarterectomy was performed on Nov. 19, 1973, which was followed by STA-MCA anastomosis 2 months later. The spasticity of extremities and left hemisparesis were gradually improved and he was able to walk without help. Case 2. On Apr. 14, 1974, a 63 year old female developed complete stroke with right hemiparesis and speech disturbance after transient ischemic attacks of 5 days duration. On Aug. 9, he was admitted and had emotional incontinence, right hemiparesis, Gerstmann's syndrome and motor aphasia. Left carotid angiogram revealed a saccular aneurysm of the middle cerebral artery and the occlusion of the distal middle cerebral arterys. These findings suggested that the occlusion was caused by embolus from the middle cerebral aneurysm, and the combined surgery with STA-MCA anastomosis and operation for the aneurysm was planned. On Aug. 30, 1974, under left frontotemporal craniotomy, aneurysmal neck clipping and aneurysmectomy were performed and thereafter, STA-MCA double anastomosis was done. One week after operation, the gradual improvement of pre-operative symptomes was noted. Recently, STA-MCA anatomosis is well known to be one of the effective operative methods for the occlusive methods for the occlusive cerebrovascular diseases and in addition, we found that the combination of STA-MCA anastomosis with other operations was effective for unusual cases presenting in this report. Furthermore, except for the occlusive cerebrovascular diseases, we usually plan STA-MCA anastomosis for the cases of 1) carotid ligation or trapping for carotid-cavernous sinus fistula and some internal carotid aneurysms, 2) some intracranial tumors with the danger involving the main cerebral arteries by operation to protect the cerebrovascular insufficiency.