Distal Middle Cerebral Artery M4 Aneurysm Surgery Using Navigation-CT Angiography

Unruptured non-traumatic dissecting aneurysm in the M4 segment of the middle cerebral artery (MCA) accompanied by complete occlusion of the ipsilateral internal cerebral artery (ICA) has never been reported. A 41-year-old man presented with an infarction manifesting as left-sided weakness and dysarthria. Magnetic resonance angiography revealed a subacute stage infarction in the right MCA territory and complete occlusion of the right ICA. Angiography demonstrated aneurysmal dilatation of the M4 segment of the right MCA. Surgery was performed to prevent hemorrhage from the aneurysm. The aneurysm was proximally clipped guided by Navigation-CT angiography and flow to the distal MCA was restored by superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. We report this rare case with literature review.     

颞浅动脉-大脑中动脉分流术在颅内复杂动脉瘤手术中的应用

目的 探讨颞浅动脉（STA）-大脑中动脉（MCA）分流术在颅内复杂动脉瘤手术中的应用效果。方法 回顾性分析开颅夹闭术治疗的2例颅内复杂动脉瘤的临床资料。夹闭动脉瘤前,先行STA-MCA分流术。结果 1例破裂动脉瘤,DSA显示右侧颈内动脉后交通段巨大动脉瘤（责任动脉瘤）+左侧颈内动脉后交通段镜像动脉瘤,伴双侧胚胎型大脑后动脉,先行STA-MCA分流术,再行动脉瘤孤立术。1例未破裂动脉瘤,DSA显示MCA分叉部大型动脉瘤位,MCA M2段下干粗大,上干纤细,上干起始部均成为瘤颈的一部分,先行STA-MCA分流术,再行动脉瘤夹闭术。2例术后均无明显神经功能障碍,CTA示动脉瘤不显影、吻合口通畅,CTP显示脑灌注良好;术后6个月,改良Rankin量表评分0分1例,1分1例。结论 STA-MCA分流术能够延长安全临时阻断的时间,在动脉瘤孤立和载瘤动脉闭塞后提供保护性血流,在理想情况下双支STA分流术还可以提供高流量血流,替代复杂的桡动脉或大隐静脉分流术,简化手术操作。这项技术有利于提高颅内复杂动脉瘤的治愈率,降低手术并发症的发生率。     

Clinical characteristics of ruptured distal middle cerebral artery aneurysms: Review of the literature

Middle cerebral artery (MCA) aneurysms usually arise at the primary MCA bifurcation or trifurcation. Distal MCA aneurysms are rarely considered as sources of aneurysmal subarachnoid hemorrhage (SAH). It has been reported that ruptured distal MCA aneurysms are associated with head trauma, neoplastic emboli, arterial dissection, or bacterial infection. We experienced five cases of ruptured distal MCA aneurysms and evaluated their clinical characteristics. Retrospective analysis of aneurysmal SAH at Kobayashi Neurosurgical Neurological Hospital was performed from January, 2004 to December, 2014. Clinical characteristics of ruptured distal MCA aneurysms were analyzed using our database. Among 191 aneurysmal SAH patients, there were five ruptured distal MCA aneurysms. All patients did not have any specific medical problems such as infectious disease, head trauma, or cardiac disorders. The incidence of ruptured distal MCA aneurysm was higher than expected and was equivalent to 9.4% of the total ruptured MCA aneurysms. Strong male predominance (80%) and M2–3 junction aneurysm preponderance (80%) were observed. In addition, there were only two patients (40%) with intracerebral hematoma in our study. We reported five cases of ruptured distal MCA aneurysms. Although ruptured distal MCA aneurysms are thought to be rare as sources of aneurysmal SAH, the incidence of ruptured distal MCA aneurysm was 9.4% of all ruptured MCA aneurysms in our study. Ruptured distal MCA aneurysms should be considered as sources of aneurysmal SAH without intracerebral hematoma.     

大脑后动脉远端动脉瘤的血管内介入治疗

目的 探讨大脑后动脉远端动脉瘤的血管内介入治疗方法及特点.方法 10例动脉瘤,P2段6例(囊状2例、梭形2例、夹层2例)、P2-P3交界处1例(夹层)、P3段3例(夹层).对于囊状动脉瘤采用弹簧圈栓塞并保留载瘤动脉的方法;梭形动脉瘤采用支架重建瘤腔的方法;P2段及P2-P3交界夹层动脉瘤采用弹簧圈栓塞并闭塞载瘤动脉的方法;P3段夹层动脉瘤采用Glubran胶栓塞并闭塞载瘤动脉的方法.结果 随访半年至1年,预后良好.DSA复查9例,未见动脉瘤复发.结论 对于大脑后动脉远端动脉瘤,根据动脉瘤的类型及部位采用不同的血管内介入治疗方法,短期随访可以获得较好的疗效.     

Occlusion of the Middle Cerebral Artery Branch Mimicking Aneurysm

A 26-year-old man was admitted to our department due to intermittent left hemiparesis for 3 months. Magnetic resonance image showed subacute infarction in the right precentral gyrus. Digital subtraction angiography and magnetic resonance angiography revealed an aneurysmal protrusion at the right middle cerebral artery (MCA) bifurcation. It was difficult to differentiate the aneurysm from the occlusion of the middle trunk of the MCA trifurcation. Brain single photon emission computerized tomography showed a decrease in perfusion in the right posterior frontal lobe without vascular reserve. Therefore, we planned a superficial temporal artery-MCA anastomosis with an exploration of the right MCA bifurcation. Intraoperatively, the aneurysmal opacification on preoperative angiography proved to be the proximal stump of the occluded middle trunk of the MCA trifurcation. An aneurysmal protrusion at the MCA bifurcation does not always indicate an aneurysm. In diagnosing protruding vascular lesions at the MCA bifurcation, the possibility of a vascular stump should be considered according to their angioanatomical appearance and the history of the patient.     

Surgical strategies using cerebral revascularization in complex middle cerebral artery aneurysms

Objectives

To describe surgical strategies using cerebral revascularization for complex middle cerebral artery aneurysms unsuitable to microsurgical clipping.

Materials and methods

In this study, the clinical features, case management, and results in 9 consecutive patients who underwent 10 cerebral revascularization procedures between January 1999 and April 2008 were retrospectively analyzed. The patient population consisted of 6 men and 3 women whose ages ranged from 15 to 71 years (mean, 42.4 years). The size of the aneurysms ranged from 12 to 35 mm (mean, 24.3 mm). Treated aneurysms were located in the M1 segment in 2 patients, the middle cerebral artery (MCA) bifurcation in 3 patients, the distal M3 segment in 3 patients, and the anterior temporal artery (ATA; the early cortical branch of the M1 segment) in 1 patient. A total of 10 revascularizations were performed. Three aneurysms were saccular and six aneurysms were fusiform. For the fusiform aneurysms of the M1 segment in 2 patients, superficial temporal artery (STA) trunk–saphenous vein (SV)–MCA bypasses followed by trapping were performed. For the large saccular MCA bifurcation aneurysms in 3 patients, STA–MCA bypasses followed by complete neck clipping, including the revascularized branch with the preservation of the flow of the other branch, were performed in 2 cases, and a STA trunk–SV–MCA bypass secondary to direct neck clipping with the preservation of both M2 branches was performed in 1 case. For the fusiform distal MCA aneurysms, STA–MCA bypasses in 2 patients and in situ MCA–MCA bypasses in 2 patients were performed. In one case involving distal MCA fusiform aneurysm, STA–MCA bypass and MCA–MCA bypass were performed simultaneously. In a case involving fusiform ATA aneurysm, primary reanastomosis after aneurysm excision was performed in 1 patient.

Results

The post-operative 3-month Glasgow outcome scales were good recovery in 6 patients, severe disability in 1 patient, a vegetative state in 1 patient, and death in 1 patient. A follow-up angiography was performed in 6 patients and revealed a patent bypass in 5 patients. In one case treated by direct neck clipping secondary to cerebral revascularization, the angiography obtained 2 weeks later showed graft occlusion, but there were no neurologic symptoms. Among the unfavorable outcomes of 3 patients who did not undergo follow-up angiography, surgery-related morbidity secondary to cerebral infarction was due to the size discrepancy between the donor and recipient vessels in 1 patient with severe disability. In the other 2 patients, the preoperative conditions were Hunt and Hess grade V.

Conclusions

Cerebral revascularization is a safe and effective technique of treatment for selective cases of complex large or giant aneurysms and unclippable fusiform aneurysms in the MCA.     

Stent-Assisted Coil Embolization for the Proximal Middle Cerebral Artery Fusiform Aneurysm

Middle cerebral artery (MCA) fusiform aneurysms often have an unfavorable geometry that may limit surgical or endovascular treatment. Herein, we present a case of a fusiform aneurysm of the proximal MCA, which was successfully treated using stent-assisted coil embolization. A 42-year-old man presented with repeated headache and syncope. Five years earlier, a right MCA aneurysm had been treated by aneurismal wrapping. Magnetic resonance images (MRI) revealed a partially-thrombosed proximal MCA aneurysm at the right perisylvian region. Digital subtraction angiography (DSA) revealed a multilobulated fusiform-shaped aneurysm. The patient underwent stent-assisted coil embolization under general anesthesia and symptoms resolved postoperatively. A three-month follow-up angiography revealed no recanalization of the aneurysm and indicated tolerable blood flow through the right MCA, as compared to the preoperative angiography. We suggest that in selected patients, stent-assisted coil embolization of proximal MCA fusiform aneurysms can be an effective treatment modality.     

Saccular Aneurysm at the Anterior Communicating Artery Complex Associated with an Accessory Middle Cerebral Artery : Report of Two Cases and Review of the Literature

Accessory middle cerebral artery (MCA) is an infrequent vascular anomaly of the brain. Cerebral aneurysms associated with this anomalous artery are also very rare. To our knowledge, there have only been ten previous reports of an aneurysm associated with accessory MCA. The authors present two patients with accessory MCA-related aneurysms. A 38-year-old male and a 59-year-old female both presented with sudden-onset severe headache. In both patients, computed tomography (CT) scan revealed subarachnoid hemorrhage. A subsequent angiogram demonstrated an accessory MCA arising from the anterior cerebral artery (ACA) and a saccular aneurysm at the anterior communicating artery (ACoA) complex associated with an accessory MCA. Surgical clipping allowed for complete exclusion of the aneurysm from the arterial circulation. Based on our review of the ten cases of aneurysms associated with accessory MCA documented in the literature, we suggest that accessory MCA-related aneurysms can be classified according to whether the accessory MCA originates from the proximal A1 segment or from the ACoA complex. We also emphasize the importance of precise interpretation of preoperative angiograms and intraoperative precaution in determining the presence of this anomalous artery prior to temporary clip placement.     

颞下入路显微外科治疗大脑后动脉P2段动脉瘤

目的 总结1998-2008年以来治疗的10例大脑后动脉第2段(P2段)动脉瘤的手术治疗经验及临床效果.方法 10例患者均行颞下入路,其中2例联合翼点入路.8例行动脉瘤瘤颈夹闭或塑形夹闭并保留载瘤动脉通畅,2例巨大动脉瘤行动脉瘤孤立术.结果 手术治疗的10例患者9例术后恢复良好,1例动脉瘤孤立术后发生大脑后动脉供血区脑组织缺血性梗死,出现暂时性轻偏瘫和同向性偏盲,经高压氧治疗3周后恢复.结论 P2段动脉瘤有形成巨大动脉瘤的倾向.对于有经验的医师,颞下入路是相对简便、快速和安全的手术入人路.     

Fenestration of the middle cerebral artery and aneurysm at the site of the fenestration

Abstract

The authors report the case of a patient who presented a ruptured aneurysm of the anterior communicating artery and an unruptured aneurysm of the middle cerebral artery arising at the site of a fenestration of the MCA. The fenestration was undiagnosed on the preoperative angiogram but discovered during the surgery carried out for clipping of the aneurysms. In the literature, cases of fenestration of the MCA are sporadically reported and are incidental findings; an aneurysm may be associated on an artery other than the fenestrated MCA; an aneurysm arising at the site of the MCA fenestration is a very rare occurrence.     

后循环动脉瘤显微外科手术治疗

目的 探讨后循环动脉瘤手术适应证和治疗效果.方法 纳入42例共44个后循环动脉瘤,包括基底动脉动脉瘤26例(27个)、椎动脉动脉瘤16例(17个).其中15例分别行颈外动脉-大脑后动脉P2段(4例)、颈内动脉-大脑后动脉P2段(2例)、颌内动脉-大脑后动脉P2段(2例)、椎动脉颅内外段(2例)、枕动脉.小脑后下小动脉(5例)搭桥联合动脉瘤孤立术;余27例行单纯动脉瘤夹闭术.结果 经随访共37例(基底动脉顶端动脉瘤14例、基底动脉主干动脉瘤3例、椎动脉动脉瘤9例、小脑后下动脉动脉瘤5例、大脑后动脉P1～P2段交界处动脉瘤4例、小脑上动脉动脉瘤l例和小脑前下动脉动脉瘤1例)患者恢复正常生活活动能力,无一例发生手术相关性神经功能障碍,恢复良好率达88.09%.其余5例患者,1例(基底动脉顶端动脉瘤)术后出现严重神经功能缺损症状与体征,生活不能自理;2例(1例基底动脉顶端动脉瘤、1例基底动脉主干动脉瘤)因术后发生脑干缺血,围手术期死亡;2例(椎动脉动脉瘤)复发患者经再次治疗康复.结论 对于不宜直接行手术夹闭的后循环动脉瘤,为了避免因夹闭动脉瘤和延长临时阻断载瘤动脉时间而发生术后脑缺血事件.可选择颅内外血管搭桥联合动脉瘤孤立术,以避免动脉瘤夹闭术带来的危险.     

大脑后动脉第2段动脉瘤

目的对本院1990年以来治疗的11例大脑后动脉第2段(P2段)动脉瘤的临床和手术处理进行回顾性分析.方法 11例患者中,10例行手术治疗,其中6例经颞下入路、4例经翼点入路.5例行动脉瘤瘤颈夹闭或塑形夹闭并保留载瘤动脉通畅,5例巨大动脉瘤行动脉瘤孤立切除术;另l例行血管内弹簧栓栓塞术.结果手术治疗的10例患者8例术后恢复良好;其中包括5例动脉瘤夹闭者以及3例动脉瘤孤立者,另外2例动脉瘤孤立术后发生大脑后动脉供血区脑组织缺血性梗死,出现暂时性轻偏瘫和同向性偏盲.l例动脉瘤血管内栓塞术后动脉瘤消失,载瘤动脉通畅,恢复良好.结论 P2段动脉瘤多见于年轻人,有形成巨大动脉瘤的倾向.手术以经翼点入路和颞下入路显露为主,对必需行动脉瘤孤立者可行载瘤动脉重建以避免出现缺血性脑损害.     

Coil embolization of an incidental posterior cerebral artery aneurysm after initial OA-PCA bypass surgery

Aneurysms of the posterior cerebral artery (PCA) are rare and imply a variety of treatment modalities. We present a case of an incidental, nonruptured posterior cerebral artery aneurysm, which was successfully occluded by coil embolization after a bypass between the occipital artery and the distal posterior cerebral artery was created. MR imaging in a neurologically normal 26-year-old man, performed in the course of a work-up for nonrelated symptoms, incidentally revealed a partially thrombosed and calcified aneurysm of the left posterior cerebral artery (P2 segment). This was confirmed by angiography. Due to aneurysm configuration and localization in the asymptomatic patient, primary clipping or endovascular occlusion was considered to be too hazardous. Four weeks after successful microvascular connection of the left occipital artery to the distal posterior cerebral artery, the PCA was occluded at the level of the aneurysm with a detachable coil. The patient remained asymptomatic, without visual field defects. The above presented combined microvascular (bypass) and endovascular (coil embolization) treatment with excellent result should be considered as alternative in patients with nonruptured, asymptomatic P2 aneurysms, which are high risk for primary clipping or endovascular occlusion.     

Extracranial to intracranial bypass for the treatment of cerebral aneurysms in the pediatric population

Cerebral aneurysms are rare in the pediatric population, making a definitive treatment algorithm difficult. Microsurgical clipping is the first choice for treatment but is not always feasible, while high recurrence rates and radiation exposure make endovascular options less favorable. Extracranial-intracranial (EC-IC) bypass, though not commonly performed in the pediatric aneurysm population, has been reported in a small number of studies to be both safe and effective for the management of cerebral aneurysms. The authors present the case of a child with a distal middle cerebral artery (MCA) aneurysm in eloquent territory, successfully treated with a superficial temporal artery (STA) to MCA bypass and trapping. A review of the current literature on pediatric EC-IC bypass in the treatment of intracranial aneurysms is presented.     

Distal calcarine fusiform aneurysm: a case report and review of literature

A 50 year old female who was operated for atrial septal defect 8 years back, presented with clinical features suggestive of subarachnoid haemorrhage (grade I, Hunt and Hess). CT scan of brain revealed haemorrhage in all the supratentorial basal cisterns, sylvian cistern and small haematoma in the left occipital lobe. Conventional CT and MR angiography revealed aneurysm in relation to distal part of the calcarine branch of the left posterior cerebral artery (PCA). Left occipital craniotomy in prone position followed by deep dissection in the occipital lobe showed fusiform aneurysm of the distal part of the calcarine branch. PCA aneurysms constitute only 0.2 to 1% of all intracranial aneurysms and among them distal PCA aneurysms are most rare, constituting only 1.3%. They too are mostly seen at the bifurcation of the PCA. The present case however, is unique in the sense that it has developed as a fusiform aneurysm in the distal part of the calcarine branch. To the best of our knowledge this is rare among the rarest.     

Ossified peripheral middle cerebral artery aneurysm in a 30-year-old man

A 30-year-old man presented with a history of several convulsive episodes. A CT scan showed a calcified focus in the right temporal lobe. Cerebral angiography yielded no abnormal findings. At craniotomy, the M3 portion of the middle cerebral artery was found to terminate with a blind end at the junction with the calcified mass. A pathological diagnosis of an ossified cerebral aneurysm was made. Calcified cerebral aneurysms are not rare; they are thought to be the result of intra-aneurysmal thrombosis or degenerative changes in the aneurysmal wall. However, complete mural ossification of a cerebral aneurysm is seldom seen, and ossified peripheral middle cerebral artery aneurysms are extremely rare in young individuals. The ossified aneurysm that we report developed over a prolonged period and may have arisen during childhood.     

Anterior communicating artery aneurysm associated with an infraoptic course of anterior cerebral artery and rare variant of the persistent trigeminal artery: a case report and literature review

Infraoptic course of the precommunicating segment of the anterior cerebral artery (A1) is a rare anomaly. Furthermore, the presence of this anomaly associated with persistent trigeminal artery variant has been reported in the literature only once. We present a patient who had infraoptic course of A1 associated with an ipsilateral persistent trigeminal artery variant arising from the right internal carotid artery with no apparent connection to the basilar artery. The persistent trigeminal artery variant supplied to the right posteroinferior cerebellar artery territory. The patient also had hypoplastic left vertebral artery, superior cerebellar arteries originating from posterior cerebellar arteries bilaterally, and a bilobed aneurysm of the anterior communicating artery. The aneurysm was clipped and the infraoptic course was verified during the surgery. The post-operative course was uneventful and a follow-up arteriogram on the 7th postoperative day revealed successful obliteration of the aneurysm.We reviewed the literature with respect to presentation, associated vascular anomalies, imaging, associated cerebral aneurysms and other cerebral abnormalities, and treatment of the associated aneurysms. A discussion of the embryogenesis of this rare anomaly is also provided.     

Transient ischemic attack associated with stenosis of accessory middle cerebral artery: A case report

Accessory middle cerebral artery (MCA) is a rare anatomical variation of middle cerebral artery branching. An association of the accessory middle cerebral artery and cerebral aneurysms had been well documented. We report a patient who presented with transient ischemic attack (TIA) associated with stenosis of the accessory MCA ostium.     

颅内血管搭桥辅助治疗大脑中动脉远端梭形动脉瘤

目的探讨颅内大脑中动脉远端梭形动脉瘤的手术方法及疗效。方法回顾性分析4例大脑中动脉远端梭形动脉瘤病人的临床资料,其中多发1例,单发3例。巨大血栓性动脉瘤2例,动脉硬化性动脉瘤2例。均采用扩大翼点入路,取颞浅动脉作为移植血管,行动脉瘤远近端动脉和移植血管的端侧或端端吻合。吻合成功后行动脉瘤孤立或切除术。术中体感诱发电位监测以便及时发现术中脑缺血。结果动脉瘤切除2例,孤立2例。影像学复查显示无脑梗死,搭桥血管通畅。术后发生一过性口角抽搐1例,治疗后消失;双侧动眼神经麻痹1例,与手术牵拉有关。随访8～14个月,均恢复,无神经功能障碍。结论颅内动脉搭桥手术难度较大,术前精确评估动脉瘤及其周围血管的情况,制定合理的手术计划,可有效的治疗巨大难治性动脉瘤。     

Giant Serpentine Aneurysm of the Middle Cerebral Artery

Giant serpentine aneurysms are rare and have distinct angiographic findings. The rarity, large size, complex anatomy and hemodynamic characteristics of giant serpentine aneurysms make treatment difficult. We report a case of a giant serpentine aneurysm of the right middle cerebral artery (MCA) that presented as headache. Treatment involved a superficial temporal artery (STA)-MCA bypass followed by aneurysm resection. The patient was discharged without neurological deficits, and early and late follow-up angiography disclosed successful removal of the aneurysm and a patent bypass graft. We conclude that STA-MCA bypass and aneurysm excision is a successful treatment method for a giant serpentine aneurysm.