Intracranial Vertebral Artery Aneurysms: Clinical Features and Outcome of 190 Patients

Bypass Surgery for Vertebral Artery and Posterior Inferior Cerebellar Artery Fusiform Aneurysms: Surgical Technique and Key Lessons

Fusiform vertebral artery (VA) aneurysms are challenging to treat due to their pathophysiology, morphology, and anatomic location.1,2 Endovascular treatments are considered to be a widely adopted safe option for this pathology.1 Open microsurgical treatment is considered for complex anatomy, important branch involvement, poor collateral flow, or failed endovascular therapy.3-7 This report aims to show the flow-replacement strategy and bypass technique for a VA aneurysm with complex anatomy and branch involvement. A 24-year-old man presented to our clinic with a bilateral fusiform VA aneurysm discovered during workup of progressive headaches. Further investigation revealed that the left-side aneurysm was mostly thrombosed and the posterior inferior cerebellar artery arose from the aneurysm dome with a fusiform enlargement within a few millimeters from the branching point. After evaluating all management options, the patient decided on surgical treatment of the left VA aneurysm. We performed an occipital artery to posterior inferior cerebellar artery end-to-side anastomosis distal to the fusiform enlargement, followed by trapping of the aneurysm and dome resection (Video 1). Antegrade flow to the distal VA was reestablished using a radial artery interposition graft, thus preventing any flow alterations that may cause growth or rupture of the contralateral aneurysm caused by increased hemodynamic stress if the ipsilateral VA flow is not preserved.8 After in-hospital physical rehabilitation, the patient was discharged with a modified Rankin Scale score of 1. The contralateral aneurysm is managed with serial imaging and treatment will ensue if there is clinical-radiologic evolution. The patient consented to the procedure and publication of his image.

Outcomes following surgical and endovascular treatment of extracranial vertebral artery aneurysms (VAA): a systematic evaluation of the literature

Extracranial vertebral artery aneurysms are rare complications resulting from trauma and multiple different diseases. However, the difference between clinical and surgical profiles is well understood. To investigate the clinical and interventional outcomes following extracranial vertebral artery aneurysms (VAA) treatment through a systematic review of the literature to date, an electronic database search for full-text English articles was conducted following PRISMA guidelines. The search yielded results on clinical and surgical outcomes for extracranial VAAs. These results included patient-specific risk factors, indications, and techniques. Our literature search resulted in 561 articles, of which 36 studies were qualified to be included in the analysis. A total of 55 patients with multiple various extracranial VAA incidents were included. The mean age of subjects was 42 years (ranging from 13.0 to 76.0 years), and the majority of patients were males (71%, n =39). Blunt trauma was the most frequent risk factor for extracranial VAA formation (35%, n = 19). The majority of aneurysms (60%) were dissected in nature. The most common form of treatment for extracranial VAAs was the use of a flow diverter (24%, n=13). Overall, five (9%) patients had long-term adverse neurological complications following intervention with 5% (n=3) mortality, 2% (n=1) resulting in unilateral vocal cord paralysis, and 2% (n=1) resulted in a positive Romberg sign. The mortality rate is 15.7% in the surgical group, whereas the endovascular treatment did not result in any mortality. The endovascular approach is a safe and effective treatment of extracranial VAAs due to its relatively low overall complication rate and lack of resulting mortality. This is in contrast to the surgical approach which results in a higher rate of complications, recurrence, and mortality outcomes. An understanding of the factors and clinical outcomes associated with the incidence of extracranial VAAs is essential for the future improvement of patient outcomes.

Medullary branches of the vertebral artery: microsurgical anatomy and clinical significance

BACKGROUND

Since the medullary arteries are of a great neurologic and neurosurgical significance, the aim was to perform a detailed microanatomic study of these vessels, as well as of the medullary infarctions in a group of patients.

METHODS

The arteries of 26 halves of the brain stem were injected with India ink and gelatin, microdissected and measured with an ocular micrometer. Neurologic and magnetic resonance imaging (MRI) examinations were performed in 11 patients.

RESULTS

The perforating medullary arteries, averaging 6.7 in number and 0.26 mm in diameter, most often originated from the anterior spinal artery (ASA), and rarely from the vertebral (VA) (38.5%) and the basilar artery (BA) (11.6%). They supplied the medial medullary region. The anterolateral arteries, 4.8 in number and 0.2 mm in size, most often arose from the ASA and PerfAs, and nourished the anterolateral region. The lateral arteries, 2.2 in number and 0.31 mm in diameter, usually originated from the VA and the posterior inferior cerebellar artery (PICA). They supplied the lateral medullary region. The dorsal arteries, which mainly arose from the PICA and the posterior spinal artery (PSA), nourished the dorsal region, including the roof of the 4th ventricle. The anastomotic channels, averaging 0.3 mm in size, were noted in 42.3%. Among the medullary infarctions, the lateral ones were most frequently present (72.8%).

CONCLUSION

The obtained anatomic data, which can explain the medullary infarctions symptomatology, are also important in order to avoid damage to the medullary arteries during neurosurgical and neuroradiologic interventions.

Three-Dimensional Reconstruction and Numerical Simulation of Intracranial Aneurysm for Sectional Anatomy Based on Computed Tomography Angiography

Objective: The mortality of rebleeding after ruptured intracranial aneurysms was more than 40%. It is essential to identify the intracranial artery in sectional anatomy. However, it is difficult for students to understand the intracranial artery in the section. Therefore, the purpose of this study is to explore the application effect of three-dimensional (3D) reconstruction and numerical simulation of intracranial aneurysm for sectional anatomy based on computed tomography angiography (CTA). Method: Sixty students in medical imaging specialty of our university were divided into two groups. The control group was taught with conventional sectional anatomy and CT images, while the observation group was taught with 3D reconstruction and numerical simulation of intracranial aneurysm. The teaching characteristics and teaching effects were analyzed and compared between the two groups. Result: The 3D reconstruction can accurately express the size, direction, and adjacent relationship of aneurysms. Through rotation of the 3D image, students can easily understand the name and location of cerebral arteries. Combined with the function of 3D positioning, each blood vessel can automatically and accurately locate in the transverse, coronal, and sagittal plane. Abnormal wall shear stress was easily found in the intersection of cerebral artery circle, which was the physiological basis for the occurrence of aneurysms. There was a high shear zone in the root of an aneurysm, which was the physiological factor of rupture. The scores of sectional specimen identification, drawing examination, and theoretical assessment in the observation group were significantly higher than those in the control group (P < 0.05). Conclusion: The 3D reconstruction and numerical simulation can directly display the 3D morphological and physiological characteristics of intracranial aneurysms, which is convenient for students to understand and memorize. It can reach a good teaching effect in sectional anatomy.

Posterior Circulation Aneurysms: A Critical Appraisal of a Surgical Series in Endovascular Era

The advent of the endovascular era has apparently decreased the role of microneurosurgery for many of the posterior circulation aneurysms. This study consists of a critical appraisal of a retrospective surgical series regarding posterior circulation aneurysms, targeted to define whether microneurosurgery still has a role for some of these. In 28 years, 157 aneurysms were surgically treated, 98 of which ruptured. The Average patient age was 56.7 ± 14.2 years, while in hemorrhagic cases, the mean Hunt-Hess score was 2.17 ± 0.8. Basilar tip, vertebral artery and proximal posterior inferior cerebellar artery were the most frequently involved sites. The treatment consisted of 128 clippings, 19 trappings, 7 wrappings, and 3 bypasses. A total exclusion was achieved in 88.5% of the aneurysms. An average follow-up of 67.1 ± 61.3 months proved no recurrences. The best results were observed in patients <65 years old who harbored small-to-regular aneurysms of the basilar tip, distal cerebellar arteries, or vertebral artery.Clipping proved to be a definitive and durable treatment for a large part of posterior circulation aneurysms, whereas bypass allows for treating aneurysms not amenable for coiling, stenting, or clipping. The present study confirms that microneurosurgery continues to have a paramount role within neurovascular pathology.

Microneurosurgical Management of Posterior Inferior Cerebellar Artery Aneurysms: Results of a Consecutive Series

Aneurysms of the posterior inferior cerebellar artery (PICA) are uncommon. The complex anatomy of PICA and its intimate relationships with medulla, lower cranial nerves, and jugular tubercle makes the surgical treatment of these aneurysms fascinating. The reported is study aimed at a critical review of the overall results of a personal series of PICA aneurysms, treated by the senior author, R. Galzio. Demographics, charts, videos, outcome, and follow-up of a cohort of PICA aneurysms managed in the last 10 years were retrospectively analyzed, focusing only upon those treated with microneurosurgery. Twenty-five patients, harboring a single aneurysm, were operated on. Fifteen aneurysms were ruptured. Nineteen were proximal, all of these being been treated through a far-lateral approach. Trans-condylar or trans-tubercular variants were rarely necessary and however reserved to peculiar cases. Twenty-three aneurysms underwent direct treatment consisting of clip ligation. At 6-month follow-up, 60% of patients had a modified Rankin Score (mRS) of 0-2. Given the high anatomical variability of both PICA and patients' bony anatomy, a case-by-case meticulous preoperative imaging evaluation is mandatory for the choice of the most suitable and tailored surgical corridor which, in turn, is pivotal to achieve the best outcome.

Superficial temporal artery-superior cerebellar artery bypass and proximal occlusion through anterior petrosal approach for subarachnoid hemorrhage due to basilar artery dissection

Background:

Subarachnoid hemorrhage (SAH) due to rupture of basilar artery dissection (BAD) is extremely rare and often has a poor prognosis. Since ruptured BAD has high rate of rebleeding and mortality, treatment to prevent rerupture is mandatory in the acute phase. However, to date, no optimal treatment has been established which satisfies secure prevention of rerupture and ischemia simultaneously. Herein, we report a case of SAH due to BAD treated with proximal occlusion of basilar artery with superficial temporal artery (STA)-superior cerebellar artery (SCA) bypass, preventing rebleeding securely and ensuring adequate blood flow in the upper basilar region.

Case Description:

A 48-year-old male presenting with headache and altered mental status was found to have SAH and BAD. To prevent rerupture, proximal occlusion of basilar artery with STA-SCA bypass using anterior transpetrosal approach was performed. The postoperative course was relatively good and there is no evidence of recurrent arterial dissection.

Conclusion:

Proximal occlusion of the basilar artery combined with STA-SCA bypass was successful in preventing rerupture of BAD and ensuring blood flow in the upper basilar region. Although there is controversy regarding acute treatment for ruptured BAD, direct proximal occlusion with sufficient revascularization using bypass skull base technique may be one of the optimal treatments even in this era of endovascular treatment.

Endovascular treatment of complex vertebrobasilar junction aneurysms: A report of two cases

INTRODUCTION

Vertebrobasilar junction (VBJ) aneurysms are uncommon posterior circulation aneurysms. The treatment of VBJ aneurysms is challenging and in most cases, endovascular management is preferred over neurosurgery.

PRESENTATION OF CASE

We describe two patients with VBJ aneurysms who underwent successful neuro-interventional procedures. The first patient had concomitant basilar fenestration and was treated with balloon-assisted coiling. The second patient had difficult vascular anatomy and an anterior inferior cerebellar artery-posterior inferior cerebellar artery variant arising from the neck of the aneurysm. Braided stent-assisted coiling was done with transradial access. Both patients had a good neurologic recovery.

DISCUSSION

Endovascular management of VBJ aneurysms is often complicated by anatomic difficulties like basilar fenestration, tortuosity of proximal vessels, atheromatous changes, and vascular stenosis. We achieved good post-procedure outcomes in both the patients. Optimal management of complex VBJ aneurysms often requires some modification to the usual interventional technique.

CONCLUSION

VBJ aneurysms are generally treated with endovascular techniques. The transradial access, although rarely used by neurointerventionalists, has some distinct advantages over the transfemoral access, especially when dealing with right-sided VBJ aneurysms with marked tortuosity of proximal great vessels.

Treatment of intracranial vertebral artery dissecting aneurysms involving the posterior inferior cerebellar artery origin

Background

Vertebral artery dissecting aneurysm (VADA) involving the origin of the posterior inferior cerebellar artery (PICA) is a complex disease entity in which the dual goals of preventing future rebleeding and maintaining perfusion of the lateral medulla must be considered. We present an illustrative case and review the literature surrounding treatment strategies.

Case Description

We report a patient presenting with extensive subarachnoid hemorrhage due to rupture of an intracranial VADA involving the PICA origin. After consideration of the patient's cerebral vasculature and robustness of collaterals, a flow-diverting stent was placed with angiographic resolution of the lesion and maintenance of antegrade PICA flow. Ultimately, the patient experienced a contralateral intraparenchymal hemorrhage leading to death. Review of the literature identified 124 cases of VADA involving the PICA origin described over the past decade. The methods of surgical and endovascular treatment of these cases were reviewed, with particular focus on the rationale of treatment, outcomes, and complications.

Conclusion

Numerous treatment options for VADA involving PICA have been reported with different risk and benefit profiles. Flow-diverting stents appear to offer the most favorable balance of securing the aneurysm and avoiding medullary infarction, but the risks and optimal anti-thrombotic treatment strategy are incompletely understood. In select cases, in which the surgical risk is low or in which the anatomy is favorable (e.g., nondominant parent vessel or robust collateral circulation in the involved territories), parent artery trapping with or without microsurgical revascularization can be considered.

Ruptured posterior circulation aneurysms: epidemiology, patterns of care, and outcomes from the Swiss SOS national registry

BACKGROUND

The treatment of ruptured posterior circulation aneurysms remains challenging despite progresses in the endovascular and neurosurgical techniques.

OBJECTIVE

To provide epidemiological characterization of subjects presenting with ruptured posterior circulation aneurysms in Switzerland and thereby assessing the treatment patterns and neurological outcomes.

METHODS

This is a retrospective analysis of the Swiss SOS registry for patients with aneurysmal subarachnoid hemorrhage. Patients were divided in 3 groups (upper, lower, and middle third) according to aneurysm location. Clinical, radiological, and treatment-related variables were identified and their impact on the neurological outcome was determined.

RESULTS

From 2009 to 2014, we included 264 patients with ruptured posterior circulation aneurysms. Endovascular occlusion was the most common treatment in all 3 groups (72% in the upper third, 68% in the middle third, and 58.8% in the lower third). Surgical treatment was performed in 11.3%. Favorable outcome (mRS ≤ 3) was found in 56% at discharge and 65.7% at 1 year. No significant difference in the neurological outcome were found among the three groups, in terms of mRS at discharge (p = 0.20) and at 1 year (p = 0.18). High WFNS grade, high Fisher grade at presentation, and rebleeding before aneurysm occlusion (p = 0.001) were all correlated with the risk of unfavorable neurological outcome (or death) at discharge and at 1 year.

CONCLUSIONS

In this study, endovascular occlusion was the principal treatment, with a favorable outcome for two-thirds of patients at discharge and at long term. These results are similar to high volume neurovascular centers worldwide, reflecting the importance of centralized care at specialized neurovascular centers.

Fusiform vertebral artery aneurysms involving the posterior inferior cerebellar artery origin associated with the sole angiographic anterior spinal artery origin: technical case report and treatment paradigm proposal

Fusiform aneurysms of the vertebral artery (VA) involving the posterior inferior cerebellar artery (PICA) origin are uncommon and challenging. The anterior spinal artery (ASA) commonly originates from a unilateral ramus just distal to the PICA. Occlusion of an unpaired ASA can result in bilateral medial medullary syndrome. The authors propose a treatment paradigm for ASA preservation based on the artery's proximity to fusiform VA aneurysms, and they present 3 representative cases. In the first case, they performed a V3-PICA bypass using an interposition graft and then performed endovascular coil embolization of the parent VA. A complete occlusion of the aneurysm and VA was complicated by ASA thrombosis. The subsequent cases were treated with PICA-PICA bypass and subsequent endovascular embolization of the VA. Filling of the sole angiographic ASA remote from the aneurysm was preserved in both cases. The anatomy of the ASA is the most critical determinant of treatment recommendations for fusiform VA aneurysms involving PICA. When the ASA originates from the aneurysm, proximal occlusion with or without a PICA bypass is suggested. In cases in which the ASA is removed from the aneurysm, the authors recommend revascularization followed by endovascular sacrifice. When the aneurysm is immediately adjacent to the ASA, revascularization and open trapping should be considered.

The open access video collection project "Hernesniemi's 1001 and more microsurgical videos of Neurosurgery": A legacy for educational purposes

BACKGROUND

Neurosurgical educational programs and courses are helpful to improve the quality of training. Moreover, nowadays, online activities may represent a very useful tool to globally enhance neurosurgical education. The "Hernesniemi's 1001 and more microneurosurgical videos" project aims to show the microsurgical style developed by the senior author and his TEAMs in more than 40 years of experience.

METHODS

More than 1100 high-definition videos of microneurosurgical operations performed by the senior author were carefully edited. These videos illustrate the philosophy of "simple, clean, fast and preserving the normal anatomy" while offering a step by step guide of different neurosurgical procedures.

RESULTS

All the aforementioned material is well organized in an electronic videobook, freely available in Surgical Neurology International. The book also includes comments of great current neurosurgeons and writings of the authors and editors.

CONCLUSION

We are sure that our project will be able to instill in and spread across the neurosurgical community the microneurosurgical style of the senior author, thus representing an efficient educational tool for surgeons all around the world.

Three Cases of Ruptured Basilar Artery Dissection: From Diagnosis to Endovascular Treatment

BACKGROUND

Ruptured basilar artery dissections are rare, and prognosis is often disastrous.

CASE DESCRIPTION

We report 3 recent cases of ruptured dissection from imaging diagnosis to endovascular treatment, presenting 3 different types of dissection and 3 different treatment approaches. These 3 patients presented major subarachnoid hemorrhage (Fisher grade 4): 2 of them were in a coma (World Federation of Neurosurgical Societies Grading System [WFNS] 5), and 1 patient presented with headache only (WFNS 1). Two of the 3 dissections presented a dilated pseudoaneurysm responsible for the bleeding (1 large and 1 small), and the remaining dissection was extensive. The dissection with the larger pseudoaneurysm was treated with coils, resulting in early recanalization requiring another endovascular treatment with coils and a flow diverter stent. The patient with the small pseudoaneurysm was treated with a flow diverter only. These 2 patients had a favorable outcome. The remaining patient with a large tear of the basilar artery had 3 overlapping stents, and fatal rebleeding occurred prematurely.

CONCLUSIONS

These 3 cases illustrate different patient management strategies. We discuss this challenging condition and the current position of endovascular therapeutic techniques.