Which unruptured cerebral aneurysms should be treated? A cost-utility analysis.

OBJECTIVE: To determine which unruptured cerebral aneurysms should be treated considering the risks. benefits, and costs. BACKGROUND: Asymptomatic unruptured cerebral aneurysms are commonly treated by surgical clipping or endovascular coil embolization to prevent subarachnoid hemorrhage (SAH). METHODS: We performed a cost-utility analysis comparing surgical clipping and endovascular coil embolization with no treatment for unruptured aneurysms. Eight clinical scenarios were defined based on aneurysm size, symptoms, and history of SAH from a different aneurysm. Health outcomes of a hypothetical cohort of 50-year-old women were modeled over the projected lifetime of the cohort. Costs were assessed from the societal perspective. We compared net quality-adjusted life years (QALYs) and cost per QALY of each therapy to no treatment. RESULTS: For an asymptomatic unruptured aneurysm less than 10 mm in diameter in patients with no history of SAH from a different aneurysm, both procedures resulted in a net loss in QALYs, and confidence intervals (CI) were not compatible with a benefit from treatment (clipping, loss of 1.6 QALY [95% CI 1.1 to 2.1]; coiling, loss of 0.6 QALY [95% CI 0.2 to 0.8]). For larger aneurysms (> or = 10 mm), those producing symptoms by compressing neighboring nerves and brain structures, or in patients with a history of SAH from a different aneurysm, treatment was cost-effective. Coiling appeared more effective and cost-effective than clipping but these differences depended on relatively uncertain model parameters. CONCLUSIONS: Treatment of small, asymptomatic, unruptured cerebral aneurysms in patients without a history of SAH worsens clinical outcomes, and thus is neither effective nor cost-effective. For aneurysms that are > or = 10 mm or symptomatic, or in patients with a history of SAH, treatment appears to be cost-effective.     

Small cerebral aneurysms presenting with symptoms other than rupture

BACKGROUND: Recent natural history studies have suggested that unruptured intracranial aneurysms smaller than 1 cm have a low risk of rupture. Symptomatic aneurysms may be underrepresented in natural history studies because they are preferentially treated. The authors compared the number of patients with symptoms caused by unruptured intracranial aneurysms smaller than 1 cm treated surgically at their institution with similar patients enrolled in the International Study of Unruptured Intracranial Aneurysms (ISUIA) from their institution over the same time period. METHODS: The records of all unruptured aneurysms treated surgically at the Mayo Clinic from 1980 through 1991 were reviewed. There were 97 patients with 117 unruptured aneurysms smaller than 1 cm by angiography. Aneurysms with a history of rupture or larger than 1 cm on cross-sectional imaging were excluded from analysis. The presence and characteristics of symptoms directly attributable to the aneurysm were recorded. Comparison was made with patients from the Mayo Clinic enrolled in the ISUIA retrospective natural history cohort over the same time period. RESULTS: Of the 97 patients studied, 15 presented with symptoms other than rupture (15.5%). The symptoms were third nerve deficit (seven patients), cerebral ischemia owing to emboli originating from within the aneurysm (five patients), and visual acuity loss (three patients). Eleven other aneurysms had possibly but not definitively caused symptoms; these were considered asymptomatic. No patient from the Mayo Clinic enrolled in the retrospective cohort of the ISUIA had a symptomatic aneurysm smaller than 1 cm on both angiography and cross-sectional imaging. CONCLUSIONS: Unruptured intracranial aneurysms smaller than 1 cm occasionally present with neurologic symptoms. These symptoms are typically owing to mass effect on the second and third cranial nerves or cerebral ischemia as a result of emboli originating from within the aneurysm. Patients with symptomatic unruptured aneurysms less than 1 cm at the Mayo Clinic were preferentially treated. Although existing natural history data may be applied to most unruptured aneurysms, small symptomatic aneurysms may be underrepresented in natural history studies.     

覆膜支架血管内治疗颅内动脉瘤：附九例报告

目的探讨覆膜支架治疗颅内动脉瘤的适应证和临床疗效。方法经脑血管造影检查明确诊断的9例颅内动脉瘤患者（4例颈内动脉海绵窦段宽颈动脉瘤未破裂、5例椎动脉颅内段梭形或夹层动脉瘤破裂致蛛网膜下隙出血）,动脉瘤直径4～16mm,均接受Jostent覆膜支架治疗。结果共计植入9枚Jostent覆膜支架,均获技术成功,支架顺利到达病变部位且释放后动脉瘤颈即刻覆盖完全,动脉瘤不思影,载瘤动脉血流通畅,达到即刻影像学满意效果。随访9～24个月,5例患者（2例颈内动脉、3例椎动脉）脑血管造影检查颈内动脉支架段血流通畅、无狭窄（2例）,椎动脉支架段血管呈无症状性闭塞（2例）或支架内轻度狭窄（1例）,动脉瘤均未显影;其余4例未行脑血管造影患者门诊随访。9例患者手术后均恢复正常生活与工作,无一例死亡或永久性病残。结论覆膜支架治疗颈内动脉海绵窦段宽颈大动脉瘤、椎动脉颅内段梭形或夹层动脉瘤疗效较好,值得在有手术适应证韵患者中推荐使用。     

诱发颅内动脉瘤破裂的相关因素分析

目的分析诱发颅内动脉瘤破裂的相关危险因素.方法对80例颅内未破裂动脉瘤患者进行横断面式的随访调查.I组44例患者未经受蛛网膜下腔出血(SAH);II组36例患者脑动脉经受了SAH的刺激,手术已将破裂或较大、引发相关症状的动脉瘤夹闭,仍留有未破裂动脉瘤的多发动脉瘤患者.结果共随访到53例(66.3%).I组26例,目前年龄(到随访时)8.17～76.17岁,平均46.06岁,平均随访4.02人年;II组27例,目前年龄14.83～73.25岁、平均51.74岁,平均随访6.61人年.I组5例,出院后平均1.22年因动脉瘤破裂而死亡,破裂率4.79/100人年;1例椎动脉瘤患者,出院后2.25年瘤体从27 mm增大到34mm,动脉瘤发展率1.30/100人年.II组患者无死亡,1例随访2.42年时,发现一新增的基底动脉瘤,动脉瘤形成率0.56/100人年.结论诱发颅内动脉瘤破裂的危险因素有患者年龄、性别、首发症状以及动脉瘤大小、部位等.     

覆膜支架血管内治疗颅内动脉瘤:附九例报告

目的探讨覆膜支架治疗颅内动脉瘤的适应证和临床疗效。方法经脑血管造影检查明确诊断的9例颅内动脉瘤患者(4例颈内动脉海绵窦段宽颈动脉瘤未破裂、5例椎动脉颅内段梭形或夹层动脉瘤破裂致蛛网膜下隙出血),动脉瘤直径4～16mm,均接受Jostent覆膜支架治疗。结果共计植入9枚Jostent覆膜支架,均获技术成功,支架顺利到达病变部位且释放后动脉瘤颈即刻覆盖完全,动脉瘤不显影,载瘤动脉血流通畅,达到即刻影像学满意效果。随访9～24个月,5例患者(2例颈内动脉、3例椎动脉)脑血管造影检查颈内动脉支架段血流通畅、无狭窄(2例),椎动脉支架段血管呈无症状性闭塞(2例)或支架内轻度狭窄(1例),动脉瘤均未显影;其余4例未行脑血管造影患者门诊随访。9例患者手术后均恢复正常生活与工作,无一例死亡或永久性病残。结论覆膜支架治疗颈内动脉海绵窦段宽颈大动脉瘤、椎动脉颅内段梭形或夹层动脉瘤疗效较好,值得在有手术适应证的患者中推荐使用。     

Multiple Cerebral Aneurysms Associated With Neurofibromatosis Type 1

Neurofibromatosis type 1 (NF1) is a rare disease with an incidence of approximately one in every 3000 births. NF1 is mainly recognized as a tumor suppressor. Vasculopathy in NF1 is well described in the literature, but the association between NF1 and cerebral aneurysm has not been determined. We report a case of a 67-year-old female with NF1 accompanied by 8 cerebral aneurysms. Two of the patient's unruptured aneurysms, the large distal anterior cerebral artery (ACA) aneurysm and anterior communicating artery aneurysm, were initially treated with microsurgical clipping. The peripheral ACA aneurysm gradually increased in size and ruptured after 5 years. Coil embolization was performed for the ruptured aneurysm. Four of the 5 remaining unruptured aneurysms were treated surgically. The patient is currently well, without neurological deficit, and coil embolization is scheduled for the last remaining aneurysm. NF1 is a probable risk factor for multiple cerebral aneurysms due to vessel wall vulnerability. Therapeutic indications for patients with NF1 who show multiple cerebral aneurysms include strict follow-up and aggressive treatment to avoid subarachnoid hemorrhage.     

Epidemiologic and anatomic aspects comparing incidental and ruptured intracranial aneurysms: A single centre experience

The feasibility of multicentric international data such as integrated in the PHASES score for patient counseling in unruptured intracranial aneurysms has recently been challenged. To determine, whether this data is applicable to local populations in a restricted catchment area, we performed a retrospective mono-centric analysis comparing patients with ruptured aneurysms to patients with incidental aneurysms. 200 patients with unruptured aneurysms and 197 patients after aneurysmal subarachnoid hemorrhage were analyzed for risk factors differing between the groups and to the general German population. Subgroup analysis was performed for 25 patients harboring multiple aneurysms, in 19 patients with intracavernous aneurysms and in 77 women of childbearing potential. While the preponderance of female patients was confirmed, significantly more men figured in the patient group with subarachnoid hemorrhage (36.4%) than among unruptured aneurysms (25%). Patients with bleeding events were significantly younger (51.6 years) than patients with incidental aneurysms (57.8 years). The rupture risk prediction of the PHASES score concerning aneurysm size below 7 mm and patient age over 70 years could not be confirmed, instead score points correlated to the clinical outcome after rupture. In our population, pregnant women were not overrepresented. Intracavernous carotid aneurysms contributed to the low risk profile of giant aneurysms. Thus, recommendations from pooled international data have to be adapted cautiously to local circumstances. We retained seven items with predictive value for outpatient counseling: age, smoking, hypertonus and concurrent vascular aberrations as patient characteristics and irregular shape, (increasing) largest diameter and the harboring vessel for the aneurysm.     

Intraoperative rupture in the surgical treatment of patients with intracranial aneurysms

Intraoperative rerupture (IOR) during clipping of cerebral aneurysms is a difficult complication of microneurosurgery. The aim of this study was to evaluate the incidence of IOR and analyze the strategies for controlling profound hemorrhage. A total of 165 patients with unruptured intracranial aneurysms and 46 patients with subarachnoid hemorrhage (SAH) treated surgically between April 2010 and March 2011, were reviewed. The data were collected with regard to age, sex, presence of symptoms, confounding factors and strategy for controlling intraoperative hemorrhage was analyzed in terms of location of aneurysms, timing of rupture and severity of IOR. 211 patients with 228 aneurysms were treated in this series. There were a total of six IORs which represented an IOR rate of 2.84% per patient and 2.63% per aneurysm. The highest ruptures rates occurred in patients with internal carotid artery aneurysms (25%). Surgeries in the group with ruptured aneurysms had a much higher rate of IOR compared with surgeries in the group with unruptured aneurysms. Of the six IOR aneurysms, one occurred during predissection, four during microdissection and one during clipping. One was major IOR, three were moderate and two were minor. Intraoperative rupture of an intracranial aneurysm can be potentially devastating in vascular neurosurgery. Aneurysm location, presence of SAH and surgical experience of the operating surgeon seem to be important factors affecting the incidence of IOR.     

Strategy for the treatment of inaccessible unruptured giant and large aneurysms of the internal carotid artery

Abstract

Our goal was to clarify the optimum management of the inaccessible unruptured giant and large aneurysms of the internal carotid artery (ICA). Since 1981, we have treated 18 patients with unclippable unruptured giant or large aneurysms of the ICA. Aneurysms were classified as either intracavernous or intradural. We performed proximal carotid occlusion in 12 patients and conservatively treated six patients. We retrospectively analyzed long-term outcomes in these patients. Four of seven patients with intradural aneurysm underwent proximal carotid occlusion, with good long-term outcomes. The three patients with intradural aneurysm, who were treated conservatively, died of subarachnoid hemorrhage. Eight of 11 patients with intracavernous aneurysm underwent proximal carotid occlusion, one dying of massive nasal bleeding 25 months after the procedure. In this case, the aneurysm was partially thrombosed, and residual lumen growth was revealed 22 months after proximal carotid occlusion. Cranial nerve paresis improved in five of the eight patients (63%), and two patients had a minor ischemic attack. Neurological problems failed to occur in the three patients with intracavernous aneurysm who were treated conservatively. The risk of rupture is relatively high in intradural giant and large aneurysms. Proximal carotid occlusion can effectively prevent bleeding from intradural aneurysms. Aggressive management is justified for intradural aneurysms with poor collateral circulation. Operative procedures in the management of an intracavernous aneurysm require careful consideration.     

Strategy for the treatment of inaccessible unruptured giant and large aneurysms of the internal carotid artery.

Our goal was to clarify the optimum management of the inaccessible unruptured giant and large aneurysms of the internal carotid artery (ICA). Since 1981, we have treated 18 patients with unclippable unruptured giant or large aneurysms of the ICA. Aneurysms were classified as either intracavernous or intradural. We performed proximal carotid occlusion in 12 patients and conservatively treated six patients. We retrospectively analyzed long-term outcomes in these patients. Four of seven patients with intradural aneurysm underwent proximal carotid occlusion, with good long-term outcomes. The three patients with intradural aneurysm, who were treated conservatively, died of subarachnoid hemorrhage. Eight of 11 patients with intracavernous aneurysm underwent proximal carotid occlusion, one dying of massive nasal bleeding 25 months after the procedure. In this case, the aneurysm was partially thrombosed, and residual lumen growth was revealed 22 months after proximal carotid occlusion. Cranial nerve paresis improved in five of the eight patients (63%), and two patients had a minor ischemic attack. Neurological problems failed to occur in the three patients with intracavernous aneurysm who were treated conservatively. The risk of rupture is relatively high in intradural giant and large aneurysms. Proximal carotid occlusion can effectively prevent bleeding from intradural aneurysms. Aggressive management is justified for intradural aneurysms with poor collateral circulation. Operative procedures in the management of an intracavernous aneurysm require careful consideration.     

颅内外动脉狭窄合并颅内无症状动脉瘤的血管内治疗策略研究

目的 探索颅内外动脉狭窄合并颅内无症状动脉瘤的安全和有效的血管内治疗策略。 方法 回顾性分析北京天坛医院急诊介入科2012年9月～2013年8月收住的因颅内外动脉狭窄拟行支 架治疗且合并颅内无症状动脉瘤的患者26例。对其临床、影像学资料、治疗措施及结果、并发症及预 后等进行分析。 结果 26例患者共发现≥70%的狭窄或闭塞病变54处,动脉瘤30枚（非同流域16枚,狭窄后7枚,狭窄 处3枚,狭窄前4枚）。26例患者中21例实施了狭窄病变的支架置入术,共干预25个狭窄/闭塞病变,技 术成功率100%。选择个体化的动脉瘤干预措施：16例患者的17枚动脉瘤（非同流域、直径＜5 mm、 夹层）建议随访观察;2例患者的2枚动脉瘤（直径＞5 mm、形状不规则）择期行栓塞术;5例患者的 6枚动脉瘤（狭窄后、狭窄处、多发性、直径＞5 mm、后交通段）同期行栓塞术或支架覆盖;3例患者 的5枚动脉瘤（狭窄后、分叶状、多发性、直径＞5 mm）建议介入治疗但因家属拒绝手术等原因选择随 访观察。术后发生脑室出血1例。临床随访10～21个月,所有患者均预后良好,仅发现无症状性支架内 再狭窄1例。 结论 颅内外动脉狭窄合并颅内无症状动脉瘤时根据动脉瘤与狭窄病变的位置关系,动脉瘤大小、 形态、位置、数量和患者情况等综合分析后给予个体化血管内治疗安全、有效。     

Factors affecting rapid growth of unruptured cerebral aneurysms during the acute stage of subarachnoid hemorrhage

BACKGROUND AND PURPOSE: Several unruptured cerebral aneurysms have been reported to grow and rupture. To determine which factors affect the growth of these aneurysms during the acute stage of subarachnoid hemorrhage (SAH), a retrospective review was performed.METHODS: Between January 2000 and January 2003, 130 patients with angiographically proven ruptured cerebral aneurysms were treated at our institution. Of these patients, 32 also had simultaneous unruptured aneurysms, and the total number of the unruptured aneurysms was 40, including two neck remnants which had remained since the past clipping. Seventeen patients had 17 unruptured aneurysms and two neck remnants. The unruptured aneurysms were not treated during the acute stage of SAH but had received a complete short term follow-up.RESULTS: The rapid growth of one unruptured aneurysm and two neck remnants was confirmed by a second angiogram performed on average 40 days after the first angiogram. Several candidate factors responsible for the growth of aneurysm were selected, and the results of a statistical analysis indicate that a systolic blood pressure above 200 mmHg during the acute stage of SAH and vasospasm, confirmed by transcranial Doppler ultrasound (TCD) or neurological examination, and neck remnants, are risk factors that affect the growth.CONCLUSIONS: Short term follow-up angiography is thus important for patients with untreated unruptured cerebral aneurysms after the acute stage of SAH.     

Risk of subarachnoid hemorrhage after surgical treatment of unruptured cerebral aneurysms.

BACKGROUND AND PURPOSE: Recent progress in noninvasive imaging techniques has resulted in increased detection of unruptured aneurysms. Although many neurosurgeons advocate surgical intervention for such unruptured aneurysms, the long-term results of surgery for unruptured aneurysms have not been carefully investigated. METHODS: We analyzed 173 consecutive patients who had unruptured intracranial saccular aneurysm(s) detected by angiography that was performed for reasons other than subarachnoid hemorrhage (SAH). Of those, 115 cases were surgically treated and studied. All patients were followed up for either SAH, repeat treatment of aneurysms, or death. The median follow-up period was 8.8 years. RESULTS: Four of the 115 patients suffered SAH either from a de novo aneurysm (2) or from regrowth of clipped aneurysm (1), or from regrowth after wrapping (1). Additionally, 1 patient also suffered SAH from an unstudied basilar aneurysm. One patient was incidentally found to have de novo aneurysm and underwent reoperation 14 years after the first operation. The cumulative risk for SAH for the 114 cases excluding the basilar aneurysm case was 1.4% in 10 years and 12.4% in 20 years. CONCLUSIONS: Although this study confirmed the long-term efficacy of clipping unruptured aneurysms, the risk of SAH was high compared with that in the general population, even after treatment. Considering the high mortality rate of SAH, long-term follow-up by angiography may be warranted for patients with surgically treated unruptured aneurysms.     

Intracranial aneurysms and subarachnoid hemorrhage in children and adolescents

Thirty-eight cases of symptomatic cerebral aneurysms or spontaneous subarachnoid hemorrhage in children and adolescents were observed from 1965 to 1984; 33 cases were treated from 1970 to date. This group represents 2.6% of the total number of patients with subarachnoid hemorrhage treated at our institute in the same period. The cause of subarachnoid hemorrhage was unknown in 7 cases; an intracranial aneurysm had ruptured in 29 cases, and was unruptured but symptomatic in 2 remaining cases. Three aneurysms were mycotic. The most frequent aneurysmal locations were the internal carotid bifurcation and the anterior communicating artery; peripheral branches of the middle cerebral artery were also a relatively common location. Four patients were 3 years of age or younger: each presented peculiar clinical features, and 3 of the 4 had middle cerebral artery aneurysms. The remaining 34 patients were all above 9 years of age. Two groups were identified: (a) in 14 patients between 10 and 15 years of age, the aneurysm was most commonly at the internal carotid bifurcation (37%), and an intracerebral hematoma was observed in 50% of these cases; (b) in 20 patients between 16 and 20 years of age, the most common aneurysmal location was the anterior communicating artery (35%), and intracerebral hematomas were rare (10% of cases). Among patients with aneurysms, 19 underwent surgical exclusion by clip, with 10% morbidity and 5% mortality; 5 patients in moribund conditions were not operated on; 5 patients were conservatively treated; in 2 patients the aneurysm had disappeared at a second angiography. Ischemic deterioration from vasospasm was observed only in 3 patients, all above 17 years of age, and with a consistent or thick subarachnoid blood deposition on early CT scan. Hydrocephalus was also rarely observed (13% of cases), requiring a shunt in only 3 patients. Overall management results were significantly better than in adult patients, with 73% good results and 21% deaths. The better prognosis in the group under 20 years of age is probably accounted for (a) by the frequently observed reversibility of neural injury in young patients and (b) the very low incidence of ischemic disturbances in this age group.     

Carotid ligation: what happens in the long term?

The authors reviewed a consecutive series of 115 patients who underwent common carotid ligation during the period 1954-1984. Average follow-up was 10 years. Seventy-three (63%) patients presented following a subarachnoid haemorrhage (SAH) and 42 (36%) presented with the mass effect of an unruptured aneurysm. Thirty-nine (34%) patients were lost to follow-up of whom 27 had had a previous SAH. Forty-six (63%) of the 73 patients traced had suffered a SAH and amongst this group, 11 patients (24%) died from a proven or suspected recurrent haemorrhage within 10 years of ligation. The fatal recurrent haemorrhage rate was, therefore, 2.4%/year. Thirty (71%) of the 42 patients who presented with unruptured aneurysms were traced. Seven of these (23%) died: two following haemorrhage, 1 year and 16 years after carotid ligation and three patients died as a direct consequence of carotid ligation. Check angiographic studies were available for 55 patients following carotid ligation, a mean of 8.4 years after the procedure. Thirteen were conventional angiograms and 42 were intravenous angiograms obtained using the digital subtraction technique. Seventy-six per cent of the aneurysms visualised on the initial studies were either smaller or had apparently disappeared. Only four new aneurysms were detected and in two of these instances, the initial angiographic studies had been incomplete. The authors conclude that the annual rate of fatal recurrent haemorrhage from an intracranial aneurysm following common carotid ligation is of a similar magnitude to that of the natural history of conservatively managed ruptured intracranial aneurysms. Moreover, carotid ligation apparently does not prevent haemorrhage from a previously unruptured aneurysm and the procedure appears to carry a significant morbidity and mortality, even in patients with an unruptured aneurysm.     

3.0T磁共振MRA在蛛网膜下腔出血颅内动脉瘤筛查中的应用价值

目的探讨3.0T磁共振MRA在蛛网膜下腔出血颅内动脉瘤筛查中的应用价值。方法利用3.0T磁共振对31例因蛛网膜下腔出血而筛查出脑动脉瘤患者进行回顾性分析,31例脑动脉瘤患者均行常规T1WI、T2WI及3D TOF MRA检查,对检查的信息进行MIP、MPR及VR后处理并结合原始薄层图像进行分析诊断。所有病例均由DSA最后确诊后治疗。结果小动脉瘤(<5 mm)11个,中动脉瘤(>5 mm)13个,大动脉瘤(>10 mm)9个。动脉瘤的分布:大脑中动脉瘤8个,大脑前动脉瘤7个,大脑后动脉瘤3个,前交通动脉瘤5个,后交通动脉瘤6个,基底动脉瘤1个,颈内动脉海绵窦段动脉瘤2个,椎动脉瘤1个。结论 3.0T磁共振MRA可成为蛛网膜下腔出血颅内动脉瘤筛查的有效检查方法,值得临床推广。     

Diagnosis of unruptured asymptomatic cerebral aneurysms by magnetic resonance angiography

The purpose of this study was to assess the incidence of unruptured asymptomatic cerebral aneurysms detected by magnetic resonance angiography (MRA). Three thousand patients without major neurological deficit had undergone MRA. MRA was obtained using three-dimensional time-of-flight method. Among the 3000 patients examined, 80 unruptured asymptomatic aneurysms were discovered in 68 patients (2.3%). Twenty-six were located on the internal carotid artery, 28 on the middle cerebral artery, 17 on the anterior communicating artery, 1 on the posterior cerebral artery and 8 on the vertebro-basilar artery. Thirty-seven patients underwent surgery. Mortality was zero and morbidity was 5%. Three patients who declined surgery died of subarachnoid haemorrhage in the ensuing 2.5 years.     

A Case of Wallenberg's Syndrome Presenting with Spontaneous Thrombosis of a Vertebral Artery Aneurysm

Complete spontaneous thrombosis of intracranial aneurysms is uncommon. Although this type of thrombosis is largely asymptomatic, in rare cases it can be accompanied by parent artery occlusion and ischemic stroke. There are limited reports of complete thrombosis of an unruptured aneurysm of the internal carotid artery and middle cerebral artery. Furthermore, there are no reports of occlusion of the vertebral artery caused by thrombosis of an aneurysm. The mechanisms of spontaneous thrombosis are not established. However, aneurysm morphology, arteriosclerosis, and stagnation of aneurysm flow have been suggested. Herein, we present a novel case of Wallenberg's syndrome caused by a fusiform aneurysm in which complete thrombosis of the proximal vertebral artery occurred. We discuss the mechanisms of thrombosis caused by an unruptured aneurysm, which may be useful for managing such patients who present with transient ischemic attacks.     

高压高容治疗脑血管痉挛对未曾破裂动脉瘤破裂的影响

目的探讨高压高容治疗脑血管痉挛过程中是否会增加未曾破裂的动脉瘤破裂的危险性。方法我科近5年收治的46例多发动脉瘤患者中,首次术后颅内其它部位还存在未曾破裂的和未经手术处理的动脉瘤共113个。其中19例术后行高压高容治疗,27例术后控制正常的血压及血容量,进行对比观察。结果19例术后行高压高容治疗的患者共有动脉瘤45个,治疗过程中有2个发生破裂;对照组27例共有动脉瘤68个,治疗过程中4个破裂出血;两组比较无明显差异(P>0.05)。结论颅内多发动脉瘤术后高压高容治疗不会增加未经手术处理的未曾破裂动脉瘤破裂的危险性。     

Ruptured Saccular Aneurysm Arising from Fenestrated Proximal Anterior Cerebral Artery : Case Report and Literature Review

The aneurysm arising from fenestrated proximal anterior cerebral artery (ACA) is considered to be unique. The authors report a case of a 59-year-old woman who presented with a subarachnoid hemorrhage (SAH) secondary to a ruptured aneurysm originating from the fenestrated A1 segment of right ACA. The patient had another unruptured aneurysm which was located at the right middle cerebral artery bifurcation. She was successfully treated with surgical clipping for both aneurysms. From the previously existing literatures, we found 18 more cases (1983-2011) of aneurysms associated with fenestrated A1 segment. All cases represented saccular type of aneurysms, and 79% of the patients had SAH. There were three subtypes of the fenestrated A1 aneurysms depending on the anatomical location, relative to the fenestrated segment. The most common type was the aneurysms located on the proximal end of fenestrated artery (82%). Azygos ACA and hypoplastic A1 were frequently accompanied by the aneurysm (33% and 31%, respectively), and multiple aneurysms were shown in three cases (16%). Considering that fenestrated A1 segment is likely to develop an aneurysm, which has high risk of rupture, early management may benefit patients with aneurysms accompanied by fenestrated proximal ACA.