Outcome and recanalization rate of tandem basilar artery occlusion treated by mechanical thrombectomy

BackgroundTandem basilar artery occlusions (tBAO) are defined as concomitant basilar artery and extracranial dominant vertebral artery occlusions. The prognosis of such tBAO treated by mechanical thrombectomy (MT) has been scantly reported.The purpose of our study was to compare the safety and effectiveness of MT for patients with tBAO compared to those with non-tandem basilar artery occlusions (ntBAO).Patients and methodsRetrospective analysis of a database of patients who underwent MT at two academic centres. All patients treated for BAO were retrieved. Patients with tBAO, defined as a concomitant BAO and extracranial vertebral artery (VA) occlusion or severe stenosis ≥70% (V1 or proximal V2 segment) were compared with patients with ntBAO.ResultsA total of 15 patients with tBAO and 74 patients with ntBAO were enrolled. Successful reperfusion (modified thrombolysis in cerebral infarction score ≥2b) was obtained in 73.3% versus 90.5% (OR = 0.29, 95%CI: 0.07–1.15), good clinical outcome (3-months modified Rankin scale ≤2) was reached by 26.7% versus 32.4% (OR = 0.76; 95% CI: 0.24–2.63) and mortality at 3-months was 46.7% versus 31% (OR = 1.94; 95%CI: 0.63–6) of patients with tBAO versus ntBAO, respectively. Two patients (13.3%) with tBAO and three (4%) with ntBAO had symptomatic intracranial haemorrhage (OR = 3.64; 95% CI: 0.55–24).ConclusionMechanical thrombectomy for patients with tandem basilar artery occlusion tends to be associated with lower rates of successful reperfusion and good clinical outcome, and higher rate of mortality. Larger multicentre studies are warranted to better precise the proper selection and management of such patients.     

Emergent revascularization of acute tandem vertebrobasilar occlusions: Endovascular approaches and technical considerations—Confirming the role of vertebral artery ostium stenosis as a cause of vertebrobasilar stroke

Patients suffering from acute atherothrombotic occlusion of the proximal vertebral artery (VA) and concomitant basilar artery (BA) occlusion present a grim prognosis. We describe our experience in the endovascular recanalization of tandem vertebrobasilar occlusions using endovascular techniques. The BA was accessed through the normal VA (clean-road) or the occluded, thrombotic VA (dirty-road), and stentriever-based thrombectomy was performed using antegrade or reverse revascularization variants. Seven patients underwent successful stentriever-assisted mechanical thrombectomy of the BA and five sustained concomitant VA revascularization. Stroke onset to endovascular intervention initiation (time-to-treatment) ranged from 4.5–13 hours (mean 8.6). In two of seven patients, the BA occlusion was approached with a ‘clean-road’ approach via the contralateral VA; in five of seven patients, a ‘dirty-road’ approach via the occluded VA was used. Mean time-to-recanalization was 66 minutes (range 55–82). There were no perforations, iatrogenic vessel dissections, or other technical complications. Four patients presented mild-to-moderate disability (modified Rankin Scale [mRS] 0–3) at 3 months, one remained with moderate-to-severe disability (mRS 4), and two patients died on days 9 and 23 after their strokes. Follow-up ranged from 6–45 months (mean 24 months). In selected patients with acute VA-BA occlusion, stentriever-based thrombectomy performed through either the patent or the occluded VA, may be feasible, effective, and safe. Clinical outcomes in these patients seem to equipoise the neurological outcome of patients with successful revascularization for isolated BA occlusion. This unique pair of occlusions confirms the role of VA ostium stenosis as a cause of vertebrobasilar stroke.     

A thread of hope for successful revascularization for acute embolic basilar artery occlusion due to miserable vertebral artery stump syndrome. A technical report

Acute basilar artery occlusion (BAO) is associated with major morbidities and a high mortality rate. The prevalence of acute BAO is 10.4% among patients treated with thrombectomy for acute large vessel occlusion. Vertebral artery stump syndrome (VASS) reportedly causes ischemic stroke with tandem occlusions as vertebral artery (VA) origin occlusion and BAO. The pathogenesis of ischemic stroke due to VASS can be attributed to thrombi or emboli. Acute embolic BAO due to VASS accounted for 2 of 25 cases (8.0%) of BAO treated using thrombectomy between April 2014 and May 2019 in our registry. VASS must be considered as one cause of BAO. With the initial Magnetic resonance angiography on arrival, it is difficult to distinguish between BAO due to simple cardiogenic embolus and due to embolus caused by VASS rapidly. In patients suffering from acute embolic BAO due to VASS, the presence of VA origin occlusion makes endovascular therapy (EVT) difficult to perform. Here, we report consecutive cases of thrombectomy for acute embolic BAO due to VASS, showing markedly different outcomes. VA origin occlusion severely limits the technical options for EVT. Visualization or conjecture of the origin of both or dominant VAs conceivably offers the possibility of successful EVT and may allow good outcomes.     

Navien导管辅助SolitaireAB支架治疗急性基底动脉闭塞

目的 探讨在Navien导引导管辅助下Solitaire AB支架取栓治疗急性基底动脉闭塞的临床疗效。方法 回顾性分析2016年4月至2018年3月使用Navien导引导管联合Solitaire AB支架取栓治疗的36例急性基底动脉闭塞的临床资料。结果 单纯支架取栓24例,静脉应用阿替普酶桥接+支架取栓12例;取栓次数1次10例,2次18例,≥3次8例。血管成功再通33例（91.7%）,未通3例（8.3%）;发病到血管再通时间（257.6±35.43）min。术后24 h美国国立卫生研究院卒中量表评分[（15.7±4.31）分]较术前[（28.8±5.78）分]明显降低（P<0.05）。术后3个月,预后良好21例（改良Rankin量表评分0~2分;58.3%）,预后不良15例（改良Rankin量表评分3~6分;41.7%,其中死亡4例）。结论 Navien导引导管辅助Solitaire AB支架取栓治疗急性基底动脉闭塞再通率高,临床预后较好。     

椎动脉夹层动脉瘤的影像诊断与血管内治疗

目的总结椎动脉夹层动脉瘤的影像学诊断和血管内治疗经验。方法回顾性分析18例椎动脉夹层动脉瘤的磁共振成像和血管造影影像学特点和血管内治疗经过。结果影像特点为MR内膜瓣与壁间血肿,DSA珠线征,双腔征等。12例支架治疗中4例单纯支架后造影复查不显影,8例支架联合弹簧圈栓塞7例造影复查不显影;6例载瘤动脉闭塞4例造影复查不显影,全部病人临床随访症状消失。15例DSA复查随访,夹层动脉瘤不显影,无复发。结论DSA及MR检查对椎动脉夹层动脉瘤具有诊断价值;血管内治疗如支架技术（单纯置入或联合弹簧圈栓塞）以及载瘤动脉闭塞是椎动脉夹层动脉瘤安全、有效的选择。     

Effects of and prognostic factors affecting endovascular mechanical thrombectomy of acute vertebrobasilar artery occlusion

PurposeTo investigate the clinical outcome and factors affecting the prognosis of endovascular mechanical thrombectomy of acute vertebrobasilar artery occlusion.Materials and methodsEighty-three patients with acute vertebrobasilar artery occlusion were treated with endovascular mechanical thrombectomy, and the recanalization rate, clinical outcomes at three months, modified DWI-PC-ASPECTS, and MRA-BATMAN scores were analyzed.ResultsFollowing acute mechanical thrombectomy, the TICI 2B-3 score was achieved in all patients (100%). At three-month evaluation, 56 (67.5%) patients had good prognosis with the mRS score of 0–2, including 13 (23.2%) patients who had arterial occlusion caused by emboli and 43 (76.8%) who had atherosclerotic stenosis. In analyzing factors affecting the prognosis, a significant difference (P < 0.05) existed between patients with good (mRS 0–2) and poor (mRS 3–6) prognosis in the NIHSS (17.3 vs. 31.2, P = 0.000001), modified DWI-PC-ASPECTS (10.4 vs. 7.8, P = 0.021), and MRA-BATMAN (6.3 vs. 4.6, P = 0.003) scores. Univariate Logistic regression analysis demonstrated NIHS score ≥ 21, modified DWI-PC-ASPECTS score ≤ 8.5, and MRA-BATMAN score ≤ 6.5 to be the risk factors for poor prognosis. Multivariate Logistic regression analysis revealed NIHSS score ≥ 21 as an independent risk factor for poor prognosis.ConclusionEndovascular mechanical thrombectomy is safe and effective in recanalizing occluded vertebrobasilar artery occlusion, and NIHS score ≥ 21, modified DWI-PC-ASPECTS score ≤ 8.5, and MRA-BATMAN score ≤ 6.5 are the risk factors for poor prognosis.     

A comparison of endovascular strategies in the treatment of ruptured vertebral artery aneurysms

BackgroundContemporary management of ruptured vertebral artery dissecting aneurysms (VADA) has evolved beyond proximal parent artery occlusion (PPAO) to include endovascular trapping (ET) of the diseased segment and vessel preserving stent treatments. The aim of this retrospective cohort study was to assess the outcomes of patients with ruptured VADAs who underwent endovascular management with trapping of the diseased segment as the first-line treatment approach.MethodsWe evaluated an institutional database of patients with ruptured VADAs who were treated at Auckland City Hospital from 1998 to 2017. Baseline and outcomes data were analyzed. High-grade SAH was defined as a World Federation of Neurological Surgeons or a Hunt and Hess grade of IV-V. Favorable outcome was defined as a modified Rankin Scale of 0–2.ResultsThe study cohort was comprised of 45 ruptured VADA patients with a mean age of 50 years. The mean follow-up duration was 12.9 months. ET of the diseased segment was performed in 32 cases (71.1%), PPAO of the VA was performed in 12 cases (26.7%) and reconstruction using a flow diverting stent was performed in 1 case (2.2%). The overall procedural complication rate was 13%, including procedural neurological morbidity in 4.4%. At last follow-up, no further aneurysm filling was seen in any case, and 77.8% had a favorable outcome.ConclusionET affords a favorable risk to benefit profile for patients with ruptured VADAs. ET remains a reasonable option for ruptured VADAs in patients with sufficient collateral supply to the vertebrobasilar system.     

机械再通治疗基底动脉急性闭塞的疗效分析

目的观察机械再通基底动脉急性闭塞的疗效,探讨机械再通基底动脉急性闭塞的可行性和安全性。方法回顾性分析近4年采用血管内机械再通治疗基底动脉急性闭塞7例患者的临床资料,观察术后即时效果和预后。结果 7例患者均实现机械再通。其中,3例患者因血管狭窄50%行支架成形术,1例患者因血管狭窄50%未行支架成形术,另3例有房颤病史患者无明显血管狭窄。出血死亡2例,植物存活1例,另4例恢复良好。5例存活者3月后mRS评分分别为1分1例,2分1例,3分2例,5分1例。结论机械再通治疗基底动脉急性闭塞成功率高,总体效果满意,是有效、安全的治疗方法。     

Endovascular treatment of acute basilar artery occlusion: Outcomes,influencing factors and imaging characteristics from the Tama-REgistry of acute thrombectomy (TREAT) study

ObjectiveThe effectiveness of mechanical thrombectomy (MT) for acute basilar artery occlusion (ABAO) remains unknown. We evaluated the feasibility, safety, and efficacy of endovascular treatment for ABAO.MethodsWe retrospectively investigated patients with ABAO who underwent MT using modern stent retrievers and an aspiration device between January 2015 and March 2019 at 12 comprehensive stroke centers. Functional outcomes and 90-day mortality rates were analyzed as primary outcomes. Factors influencing outcomes were analyzed as secondary outcomes. Relationships between outcome and affected area of infarction on arrival were also analyzed.ResultsSeventy-three patients were included. Good outcome (modified Rankin Scale (mRS) score 0–2) was achieved in 25/73 patients (34.2%) and the all-cause 90-day mortality rate was 23.3% (17/73). Successful recanalization (modified Thrombolysis In Cerebral Infarction grade 2b and 3) was achieved in 70/73 patients (95.9%). In univariate analyses, age, National Institutes of Health Stroke Scale score, and posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) differed significantly between good and poor functional outcome groups. Age and pc-ASPECTS were significantly associated with functional outcomes in the logistic regression model. Positive findings for the midbrain on diffusion-weighted imaging on pc-ASPECTS and brainstem score were significantly associated with poor outcomes.ConclusionMT with modern devices for ABAO resulted in highly successful recanalization and good outcomes. A positive finding for the midbrain on initial imaging might predict poor outcomes. Further studies are required to confirm our results.     

血管内支架联合弹簧圈疏松填塞技术治疗基底动脉梭形动脉瘤

目的 探讨血管内支架联合弹簧圈疏松填塞技术对基底动脉梭型动脉瘤的治疗效果.方法 广州市红十字会医院神经内科自2005年1月至2010年1月应用血管内支架联合弹簧圈疏松填塞技术治疗基底动脉梭形动脉瘤12例,回顾性分析患者的临床资料和疗效.结果 本组患者均无明显手术相关并发症;7例患者术后6～8个月内行DSA检查随访,其中6例动脉瘤完全消失,1例可见动脉瘤内部分造影剂充盈.7例患者载瘤动脉均保持通畅.结论 支架联合弹簧圈疏松填塞技术治疗基底动脉梭形动脉瘤是安全有效的治疗方法 ,预后较好.     

基底动脉动脉瘤合并胚胎型大脑后动脉自发性闭塞的诊治分析(附1例报道并文献复习)

目的 总结基底动脉动脉瘤合并胚胎型大脑后动脉（FPCA）自发性闭塞致枕叶梗死的诊治经验,以提高此类疾病的认识,避免将FPCA残端误诊为动脉瘤。方法 回顾性分析1例基底动脉动脉瘤合并FPCA自发性闭塞致枕叶梗死的临床资料。结果 病人以突发右上肢麻木及视物模糊起病,外院DWI显示左侧枕叶内侧面梗死伴左侧丘脑灶样梗死,外院头颈部CTA示左侧颈内动脉后交通动脉动脉瘤（呈梭形）、基底动脉动脉瘤以及颅内多发血管硬化狭窄。我院左侧颈内动脉造影见左侧后交通动脉闭塞残端,残端远端可见中断后又部分显影,左侧大脑后动脉P1、P2均闭塞,椎动脉造影未见P1段发育,基底动脉中段动脉瘤。结合病人DWI梗死部位及术前灌注成像所示灌注失代偿区,考虑为左侧FPCA急性闭塞引起同侧枕叶梗死,CTA所谓的“梭样动脉瘤”其实为闭塞后的残端。采用双支架套叠辅助弹簧圈栓塞治疗基底动脉中段动脉瘤,出院时改良Rankin量表评分1分。结论 FPCA自发性闭塞临床极其罕见,急性闭塞后是否行血管内治疗依然存在争议;应加强对其影像学特征的认识和了解,以避免将其闭塞后残端误当做动脉瘤。     

不同类型基底动脉闭塞机械取栓的疗效观察

目的评价机械取栓治疗不同类型基底动脉(BA)闭塞的疗效。方法回顾性分析2013年9月至2019年9月海军军医大学附属长海医院脑血管病中心连续收治的95例行机械取栓治疗的BA闭塞患者的临床资料。根据BA闭塞是否为串联病变,分为非串联病变组(67例)和串联病变组(28例)。比较两组血管成功再通(改良脑梗死溶栓分级2b~3级)的比例、90 d预后良好(改良Rankin量表评分为0~3分)的比例、术中挽救措施及不良事件发生率等的差异。结果与非串联病变组相比,串联病变组的年龄偏低(P=0.002),而男性(P=0.009)、有吸烟史(P=0.014)、缺血性卒中TOAST分型为大动脉粥样硬化型(P=0.001)以及存在一侧椎动脉发育不良(P=0.036)的比例更高。两组患者在术前及术后24 h的美国国立卫生院卒中量表评分、股动脉穿刺至BA再灌注时间、血管成功再通比例及90 d预后良好比例方面的差异均无统计学意义(均P>0.05)。串联病变组的发病至就诊时间(P=0.049)、发病至BA再灌注时间(P=0.046)均较非串联病变组延长,且术中挽救措施(包括单纯球囊扩张、急诊支架置入、静脉应用替罗非班)的使用比例均更高(均P<0.05)。两组在手术相关的不良事件及病死率方面的差异均无统计学意义(均P>0.05)。结论对于不同类型的BA闭塞患者,应用机械取栓治疗的临床结局及不良事件的发生率无明显差异,但该结论仍需进一步扩大样本量或进行随机对照试验加以证实。     

双侧椎动脉/基底动脉重度狭窄或闭塞的急性后循环梗死患者临床特点及预后分析

目的总结分析双侧椎动脉/基底动脉重度狭窄或闭塞的急性后循环梗死患者的临床特点和预后。方法收集急性后循环梗死且伴有双侧椎动脉/基底动脉重度狭窄或闭塞的住院患者资料,分析其血管危险因素、起始症状、治疗及病情演变情况,并随访90 d预后,以mRS2分定义为预后不良。结果共纳入28例患者,最常见的起始症状为孤立性头晕或眩晕(57.1%)。53.6%的患者出现病情加重,加重≥2次9例(32.1%),预后不良15例(53.6%)。预后不良组高血压3级、病情加重、加重≥2次比例明显高于预后良好组(P0.05)。病情加重≥2次组高血压3级、高脂血症、孤立性头晕或眩晕起病、预后不良和死亡比例明显高于加重2次组(P0.05)。基底动脉不显影组死亡率(75%)明显高于显影组(4.2%)(P0.05)。结论双侧椎动脉/基底动脉重度狭窄或闭塞的急性后循环梗死患者多以孤立性头晕或眩晕起病;孤立性头晕或眩晕起病和高血压3级患者病情容易加重;病情反复加重患者预后不良比例高,死亡率高;基底动脉不显影患者死亡率高。     

Endovascular recanalization for chronic symptomatic intracranial vertebral artery total occlusion: Experience of a single center and review of literature

Objective

The optimal treatment of chronic symptomatic total occlusion of the intracranial vertebral artery (ICVA) remains undefined. We report a single-center experience of endovascular recanalization for patients with chronic symptomatic ICVA occlusion who were refractory to medical therapy.

Treatment of giant/large internal carotid aneurysms: parent artery occlusion or stent-assisted coiling

Purpose: Treatment of giant/large internal carotid aneurysm is a challenge for neurologists. Previously, parent artery occlusion was the classic therapy; now the stent-assisted coil embolization has become available in recent years, but the optimal therapy is under debate. The goal of the present study was to compare two endovascular treatment modalities in terms of safety, efficacy and short-term outcomes. Methods: All the patients were divided into two groups: Group A: patients who underwent parent artery occlusion, and Group B: patients who underwent stent-assisted coil embolization. Follow-up outcomes were evaluated using the modified Rankin Scale (mRS). Results: After 12 months of follow-up, the favorable outcome (mRS: 0–2) had no statistical significance in both groups (p = 1.00). Patients in group A had greater ischemia compared with patients in group B, but the difference did not reach statistical significance (p = 0.421). In group B, patients had a higher rate of partial occlusion (p = 0.255) and recurrence (10% vs. 0%; p = 0.586). Conclusions: Stent-assisted coiling may not be superior to parent artery occlusion in selected patients after short-term follow-up. Parent artery occlusion is a simple, safe and effective treatment for large/giant internal carotid aneurysms.     

急性缺血性脑卒中血管内治疗21例临床分析

目的探讨急性缺血性脑卒中血管内治疗的方法、疗效和安全性。方法回顾性分析血管内治疗的大血管闭塞的急性缺血性脑卒中患者21例。10例为阿替普酶静脉溶栓后桥接血管内治疗,11例直接行血管内治疗。其中机械取栓12例,机械取栓+支架植入3例,单纯颈动脉支架植入3例,机械取栓+动脉溶栓1例,机械取栓+动脉溶栓+支架植入1例,单纯动脉溶栓1例。评估术中mTICI再通等级、并发症及术后随访第90天m RS评分,分析疗效与安全性。结果21例患者前循环卒中18例,后循环卒中3例。NIHSS评分平均15. 81±6. 44分。20例患者术后血管再通达mTICI 2 b-3级。术中并发出血1例,术后大量颅内出血1例,无症状少量颅内出血4例。术后高灌注综合征8例,其中4例行去骨瓣减压术,最终死亡5例(23. 81%)。术后随访第90天mRS评分0～2分8例。结论经充分评估并及时采取适宜的单一或多种血管内治疗方法对于大血管闭塞导致的急性缺血性脑卒中患者安全有效。     

颅内段椎动脉夹层动脉瘤的血管内治疗

目的探讨椎动脉夹层动脉瘤的血管内治疗方法。方法回顾性分析本手术组2006年1月~2014年5月间接诊的41例椎动脉夹层动脉瘤病例,其中35例分别采用了3种不同的血管内治疗技术,另6例进行了随诊观察。结果 41例均获得随访,时间为3~18个月。其中1例行支架辅助弹簧圈治疗的病人复发,2例未治疗的病人动脉瘤增大。结论治疗组和观察组做统计学分析(P0.01),血管内治疗椎动脉夹层动脉瘤是一种较为安全、可靠的方法,根据动脉瘤的形态、与小脑后下动脉的关系及对侧椎动脉的发育情况等因素来选择不同的血管内治疗。     

Recanalization of extracranial internal carotid artery occlusion A 12-year retrospective study*

This study aimed to summarize therapy experience of carotid endarterectomy, carotid endarterec-tomy combined with Fogarty catheter embolectomy, and hybrid surgery for the treatment of extrac-ranial internal carotid artery occlusion. The study included 65 patients with extracranial internal ca-rotid artery occlusion who underwent carotid endarterectomy, carotid endarterectomy combined with Fogarty catheter embolectomy, or hybrid surgery in the Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, China between January 2006 and December 2012. Prior to surgery, all patients underwent perfusion CT or xenon CT to evaluate the occlusion. The procedure for each patient was chosen according to digital subtraction angiography data. The carotid artery was successfully recanalized in 46 of 51 patients who underwent carotid endarterectomy, 9 of 10 patients who underwent carotid endarterectomy combined with Fogarty catheter embolectomy, and 3 of 4 patients who underwent hybrid surgery. In patients with symptomatic carotid artery occlusion, the carotid artery can be recanalized by choosing a treatment procedure based on imaging ex-amination findings.     

血管内支架技术治疗破裂的椎动脉夹层动脉瘤

目的 评价血管内支架技术治疗破裂的椎动脉夹层动脉瘤的安全性及有效性. 方法 回顾性分析第三军医大学西南医院神经外科自2004年7月至2007年1月收治的采用支架技术治疗的9例椎动脉夹层动脉瘤患者的临床资料,其中3例行单纯支架植入术,6例行支架辅助微弹簧圈栓塞术. 结果 9例患者均在首次治疗中成功植入支架或行支架辅助微弹簧圈栓塞术,椎动脉均保留通畅,无动脉瘤破裂、血栓形成等并发症发生.所有患者获4～39个月临床随访,随访过程中无再出血表现.6例患者获3～18个月造影随访,其中2例行支架辅助弹簧圈栓塞术者随访发现动脉瘤再通或增大,再次行血管内孤立术及椎动脉近端闭塞术;2例行单纯支架植入术者随访造影示动脉瘤闭塞;另1例不全闭塞. 结论 血管内支架技术能保存患侧椎动脉畅通,是一种安全有效的治疗方法,但术后应严密随访,远期疗效仍有待进一步观察.     

Endovascular treatments for posterior cerebral artery aneurysms and vascular insufficiency of fetal-type circulation after parent artery occlusion

We present a retrospective analysis of endovascular treatments for posterior cerebral artery (PCA) aneurysms and discuss the susceptibility of a fetal-type PCA to vascular insufficiency after parent artery occlusion. Among 1207 aneurysms treated with endovascular therapy between March 1997 and March 2013 in our institution, 10 patients (0.8%) presented PCA aneurysms. The principal strategy was to employ selective coil embolization for the aneurysm. However, in certain cases of fusiform or dissecting aneurysms, we performed parent artery occlusion with coils. Clinical and radiological data were collected from hospital charts and evaluated retrospectively. The mean age was 52.7 ± 15.6 years (range, 12–65 years). Five patients (50%) were admitted with a subarachnoid hemorrhage, and one patient presented with slowly developing paralysis. The remaining four patients were diagnosed incidentally. Five patients underwent selective coil embolization, and five patients underwent parent artery occlusion. All endovascular therapies were successfully performed. However, two patients in the parent artery occlusion group suffered cerebral infarction, and both patients exhibited a fetal-type PCA. The remaining three patients in the parent artery occlusion group exhibited an adult-type PCA and did not suffer a cerebral infarction. Endovascular treatment with either selective coil embolization or parent artery occlusion is safe and effective as the long as the anatomical type of the PCA is considered. Patients with a fetal-type PCA may develop vascular insufficiency upon parent artery occlusion. Neurosurgeons should attempt to preserve the parent artery using a flow-diverting stent or stent-assisted technique for a fetal-type PCA aneurysm.