Stenting from the vertebral artery to the posterior inferior cerebellar artery

De Novo Vertebral Artery Dissecting Aneurysm after Parent Artery Occlusion of the Contralateral Vertebral Artery

After treatment of unilateral vertebral artery dissecting aneurysm (VADA), de novo VADA rarely occurs on the contralateral side. In this article, we report a case of subarachnoid hemorrhage (SAH) due to de novo VADA in the contralateral vertebral artery (VA) 3 years after parent artery occlusion of unilateral VADA, with a review of the literature. A 47-year-old woman was admitted to our hospital complaining of headache and impaired consciousness. Head computed tomography showed SAH, and three-dimensional computed tomography angiography showed a fusiform aneurysm in the left VA. We performed an emergency parent artery occlusion. Three years and 3 months after the initial treatment, the patient presented to our hospital with complaints of headache and neck pain. Magnetic resonance imaging revealed SAH, and magnetic resonance angiography revealed de novo VADA in the right VA. We performed a stent-assisted coil embolization. The patient had a good postoperative course and was discharged with a modified Rankin scale score of 0. Long-term follow-up is necessary in patients with VADA because contralateral de novo VADA can develop even several years after the initial treatment.

Kissing Aneurysms of the Posterior Inferior Cerebellar Artery Treated by Anchor Coil Technique and Stenting from the Contralateral Side: A Case Report

Kissing aneurysms refer to the condition in which two cerebral aneurysms with separate necks are in contact with each other. At present, there is scarce information on kissing aneurysms occurring near the vertebral artery (VA)-posterior inferior cerebellar artery (PICA). We report the first case of VA-PICA and nonbranched PICA kissing aneurysms, which were successfully treated with contralateral stenting after the anchor coil technique using two microcatheters. A 64-year-old woman was diagnosed with a left VA-PICA aneurysm (5.5 mm) and an adjacent small PICA aneurysm (2.5 mm) with the aneurysmal walls in close contact. For stenting, microcatheters were navigated to the PICA from the contralateral side, and framing coils for the anchor were placed into each aneurysm from the ipsilateral side. Next, a Neuroform Atlas stent was deployed from the PICA to the distal side of the VA, and coiling was completed using the jailing technique. The patient had a good postoperative course, and a left vertebral angiogram revealed complete occlusion of both aneurysms after 6 months. Adequate surgical planning and application of an appropriate stent-assisted coil embolization technique contributed to the success of the procedure in this rare case.

Comparison of Parent Artery Occlusion and Stent-Assisted Treatments in Ruptured Vertebral Artery Dissecting Aneurysms

OBJECTIVE

To assess clinical outcomes of ruptured vertebral artery dissecting aneurysms, focusing on comparing parent artery occlusion (PAO) with stent-assisted treatments, and to identify risk factors for unfavorable outcomes and postprocedural complications.

METHODS

This retrospective review included 36 ruptured vertebral artery dissecting aneurysms treated between February 2009 and April 2020. Treatment modalities included PAO without stent and stent-assisted treatments. Stent-assisted treatments included PAO with posterior inferior cerebellar artery (PICA) stenting and stent-assisted coiling. Univariate and multivariate analyses were conducted to evaluate risk factors for unfavorable outcomes and postprocedural complications.

RESULTS

Patients were treated with PAO only (24, 66.7%), PAO with PICA stenting (4, 11.1%), and PAO with stent-assisted coiling (8, 22.2%). There were only fusiform aneurysms with PICA involvement in the PAO with PICA stenting group. In the stent-assisted coiling group, 4 aneurysms incorporated PICA, and 4 aneurysms involved dominant vertebral artery. Old age (odds ratio [OR] = 1.25, 95% confidence interval [CI] = 1.01-1.56, P = 0.044) and poor Hunt-Hess grade (OR = 537.99, 95% CI = 6.73-42994.1, P = 0.005) were significantly associated with unfavorable clinical outcomes after a mean follow-up of 37.5 ± 32.8 months. Fusiform dilatation shape (OR = 15.97, 95% CI = 1.52-167.38, P = 0.021) and PICA involvement (OR = 13.71, 95% CI = 1.29-145.89, P = 0.030) were independent risk factors for ischemic complications.

CONCLUSIONS

Unfavorable clinical outcomes were significantly related to old age and poor Hunt-Hess grade. There were no significant differences between treatment groups in clinical outcomes or ischemic complications. Stent-assisted treatments might be effective and safe methods for ruptured vertebral artery dissecting aneurysms.

Stent implantation in a patient with non-hemorrhagic vertebral artery dissection associated with severe, continuously progressive stenosis in the posterior inferior cerebellar artery bifurcation region: A case report

Generally, the prognosis of non-hemorrhagic vertebral artery dissection is good. Treatment should be considered when stenosis progresses or when an aneurysm is formed. However, no clear treatment policy has been established. The purpose of this case report was to describe the treatment policy for non-hemorrhagic onset vertebral artery dissection with severe stenosis around the posterior inferior cerebellar artery (PICA) bifurcation and aneurysm, where stent placement in the vertebral artery was difficult. This report describes healing without complications with stent implantation in the PICA performed to treat non-hemorrhagic vertebral artery dissection with associated severe, continuously progressive stenosis in the PICA bifurcation region. A 36-year-old woman was examined at the authors’ hospital for persistent pain in the left posterior neck. Left vertebral arteriography revealed stenosis due to dissection around the PICA bifurcation and aneurysm formation at the distal position. Due to the progression of stenosis, there were concerns about PICA occlusion, and stent implantation in the vertebral artery was performed via the PICA. Neck pain ceased immediately after surgery, and 3 months later, cerebral angiography showed favorable patency of the PICA and decreased aneurysm size. This case suggests that stent implantation in the PICA might be a useful treatment option for non-hemorrhagic vertebral artery dissection with associated severe stenosis in the PICA bifurcation region.

Treatment of Unruptured Vertebral Artery Aneurysm Involving Posterior Inferior Cerebellar Artery With Pipeline Embolization Device

Background: Treatment of unruptured vertebral artery aneurysm involving posterior inferior cerebellar artery (PICA) is challenging. The experience of pipeline embolization device (PED) therapy for these lesions is still limited.

Objective: To evaluate the safety and efficacy of the PED for unruptured vertebral artery aneurysm involving PICA.

Methods: Thirty-two patients with unruptured vertebral artery aneurysm involving PICA underwent treatment with PED were retrospectively identified. Procedure-related complications, PICA patency, clinical, and angiographic outcomes were analyzed.

Results: Thirty-two aneurysms were successfully treated without any procedure-related complications. Images were available in 30 patients (93.8%) during a period of 3–26 months follow-up (average 8.4 months), which confirmed complete occlusion in 17 patients (56.5%), near-complete occlusion in 9 patients (30%), and incomplete occlusion in one patient (3.3%). Parent artery occlusion (PAO) was occurred in 3 patients (10%). Twenty-eight of 30 PICA remained patent. The two occlusions of PICA were secondary to PAO. At a mean of 20.7 months (range 7–50 months) clinical follow-up, all the patients achieved a favorable outcome without any new neurological deficit.

Conclusion: PED seems to be a safe and effective alternative endovascular option for patients with unruptured vertebral artery aneurysm involving PICA.

Mechanical thrombectomy for acute occlusion of the posterior inferior cerebellar artery: A case report

BACKGROUND

Mechanical thrombectomy (MT) has been demonstrated to be useful for the treatment of ischemic stroke in patients with large vessel occlusions. However, recanalization by MT is not recommended for distal vessels such as second-order branches of the middle cerebral artery and posterior inferior cerebellar artery (PICA). Because of the small size and tortuosity of these arteries, the risks of using the available endovascular devices outweigh the benefits of treatment. However, MT appears to be effective in patients with primary distal vessel occlusion in eloquent areas, those with a high National Institutes of Health Stroke Scale score, and those ineligible for recombinant tissue plasminogen activator therapy. Here, we report the use of MT for treating acute occlusion of the PICA using a direct-aspiration first-pass technique (ADAPT).

CASE SUMMARY

In this case, the patient received acute occlusion of the PICA with ADAPT when right internal carotid artery stenting was performed.

CONCLUSION

With the introduction of advanced endovascular devices, MT may now be a feasible treatment for acute occlusion of the PICA.

Endovascular Treatment of Intracranial Vertebral Artery Dissection

Intracranial vertebral artery dissection (VAD) is the most common arterial dissection in intracranial arteries. Some types of VAD can heal spontaneously after reconstitution of the vessel lumen with excellent prognosis, whereas others can progress to stroke that needs treatment. Recently, endovascular treatment (EVT) has emerged and is suggested as a treatment option for VADs due to perceived low rates of procedure-related morbidity with good efficacy. In the last decade, we have accumulated our strategies to treat those VADs. Here, we try to share our experiences about VADs, including indications and methods of treatment of VADs using EVT. We perform EVT for ruptured VADs presenting with SAH and some of unruptured VADs such as VAD with recurrent or progressive ischemia, dissecting aneurysm larger than 7 mm or with mass effect, early ugly change of VADs in shape and size during follow-up period, involving the basilar artery (BA) and bilateral VADs. We present how we have done in our real practice for the last decade for treating VADs by EVT rather than reviewing and organizing so-far-published literature. We tended to occlude the rupture point by vertebral artery (VA) occlusion in non-dominant VA or stent-assisted coiling in dominant VA for ruptured VADs. We tended to reconstruct original hemodynamics using various stents for unruptured VADs. To decide what to treat and how to treat are very complicated for VADs. However, we believe that EVT is the current mainstay for treating VADs. Each technique of EVT should be determined on a case-by-case basis at the discretion of endovascular neurosurgeons and/or interventional neuroradiologists according to presenting symptoms, hemodynamic status, including sufficiency of the collateral supply and anatomic features of the vertebrobasilar artery as well as the posterior inferior cerebellar artery, anterior spinal artery, and medullary perforators.

Reconstructive treatment of symptomatic vertebral artery dissecting aneurysms with Willis covered stent: Initial experience

Background

Symptomatic vertebral artery dissecting aneurysm (VADA) is a challenging disease with controversy on treatment strategy due to anatomic configuration and their nature. Moreover, the outcomes of reconstructive treatment have not been well established.

Objective

To evaluate the safety and efficacy of reconstructive endovascular treatment (EVT) for symptomatic VADAs with Willis covered stent.

Methods

We evaluated retrospectively 13 patients with symptomatic VADAs who treated with Willis covered stent, compared with stent-assisted coiling (SAC) on the characteristics, posttreatment course, angiographic and clinical follow-up outcomes at an average of 14.4 months (range, 3–48 months).

Results

A total of 33 patients with symptomatic VADAs were reviewed, 23 of these patients with ruptured VADAs. The technical successful rate is 100% respectively in Willis covered stent (Group A) and SAC (Group B, n ​= ​20). The initial complete occlusion rate was significant higher in group A (100%) than group B (30%) (p ​< ​0.01). Major procedure-related complications were not significant different in the two groups. Serial follow-up angiograms revealed 5 recurrent VADAs in group B and no recurrence in group A (p ​> ​0.05). No obvious in-stent stenosis and no re-hemorrhage and delayed ischemic symptoms during the follow-up period. The final angiograms of all survived patients demonstrated the complete occlusion rate was higher in group A (100%) than group B (80%), but no significant statistical difference (p ​> ​0.05). Clinical outcomes were favorable in 31 (93.9%), severe disability occurred in one in group B, and only one death in group A. The final clinical outcomes were also not significant difference in the two groups (p ​> ​0.05).

Conclusions

Our initial result demonstrated reconstructive EVT with Willis covered stent provides a viable approach for selected symptomatic VADAs involving the intracranial and extracranial segments, which is similar to favorable results with SAC. However, an expanded clinical experiences and larger cohort studies are needed.

Preliminary experience of stent-assisted coiling of wide-necked intracranial aneurysms with a single microcatheter

BACKGROUND

The purpose of this study was to report our preliminary experience of stent-assisted coiling (SAC) of wide-necked intracranial aneurysms with a single microcatheter in patients with parent arteries that were small-caliber, with stenosis, or a very tortuous course.

METHODS

Between March 2018 and December 2018, we treated 394 aneurysms in 359 patients with endovascular treatment. Among 197 aneurysms treated by SAC, there were 16 cases (all wide-necked unruptured aneurysms) treated by SAC with a single microcatheter and a Neuroform Atlas stent. Follow-up angiography was performed at 6 to 12 months after SAC, and clinical follow-up was performed from 6 to 12 months in all patients.

RESULTS

The reasons for SAC with a single 0.0165-in. microcatheter were small-caliber (n = 4), stenosis (n = 2), and very tortuous course (n = 10) of the parent arteries. There was no complication related to delivering or deploying the Neuroform Atlas stent as well as no failure of selecting aneurysm by cell-through technique. All patients had a modified Rankin score of 0 at discharge and at follow-up. Initial angiographic results showed six cases (37.5%) of complete occlusion. In follow-up angiographies, 12 cases (75.0%) achieved compete occlusion.

CONCLUSION

When performing SAC of wide-necked intracranial aneurysms in parent arteries with small-caliber, stenosis, or a very tortuous course, cell-through SAC using a single microcatheter and a Neuroform Atlas stent within a 5 Fr- (or smaller) guiding or intermediate catheter might be a useful option.

Incidentally Found Double Aortic Arch While Treating Posterior Inferior Cerebellar Artery Aneurysm: Conversion from Femoral to Radial Artery Access

BACKGROUND

Asymptomatic double aortic arches are a unique occurrence.

CASE DESCRIPTION

An incidental finding of a double aortic arch in an elderly male was discovered during workup of a transient ischemic attack. The following case presentation details an effective treatment approach in cerebrovascular stenting in a patient with variant aortic arch anatomy. The initial diagnostic cerebral angiogram was performed via transfemoral approach and was quite challenging.

CONCLUSIONS

Faced with challenging anatomy, the radial artery approach is a viable option when navigating into the cerebrovascular anatomy for stenting when proximal variants such as a double aortic arch are identified.

Coil Embolization of Ruptured Proximal Posterior Inferior Cerebellar Artery Aneurysm with Contralateral Retrograde Approach for LVIS Jr. Intraluminal Support Deployment

The safety and feasibility of simple coil embolization and stent deployment for the treatment of posterior inferior cerebellar artery (PICA) aneurysms, as well as their radiologic and clinical results, have not been adequately understood. Especially, if dissecting aneurysm of proximal PICA is associated with small caliber PICA and stenosis of ipsilateral vertebral artery orifice (VAO), endovascular coiling with saving of PICA is not always easy. This 64-year-old man presented with subarachnoid hemorrhage due to a ruptured dissecting aneurysm of left proximal PICA. The aneurysm was irregularly fusiform in nature with a shallow PICA orifice (1.4 mm) and narrow caliber (0.9–1.5 mm). Moreover, the ipsilateral VAO showed severe stenosis (1.8 mm). We performed bifemoral puncture and chose additional route from right vertebral artery to left vertebrobasilar junction for retrograde approach and deployment of LVIS Jr. intraluminal support at proximal PICA. And then, the antegrade approach and coiling of aneurysm was done. Despite of transient thrombus of PICA, the aneurysm was successfully secured with preservation of whole PICA course. For preservation of narrow PICA with ipsilateral VAO stenosis, the contralateral approach and deployment of LVIS Jr. intraluminal support may be considered.

De novo vertebral artery dissecting aneurysm after internal trapping of the contralateral vertebral artery

We present the case of a de novo vertebral artery dissecting aneurysm (VADA) after endovascular trapping of a ruptured VADA on the contralateral side. The first ruptured VADA involved the posterior inferior cerebellar artery, which was successfully treated by endovascular internal trapping using a stent. A follow-up study at 3 months revealed a de novo VADA on the contralateral side. The second VADA was successfully embolized using coils while normal arterial flow in the vertebral artery was preserved using a stent. Increased hemodynamic stress may cause the development of a de novo VADA on the contralateral side.

Retrograde Stent-assisted Coil Embolization of Wide-neck or Branch-incorporated Posterior Communicating Artery Aneurysm

Endovascular coil embolization using a balloon- or stent-assisted technique for the treatment of wide-necked posterior communicating artery (PcomA) aneurysms is well established. However, complete aneurysm occlusion with preservation of the PcomA can be difficult in case of wide-neck aneurysms with a PcomA incorporation. We present two cases of stent-assisted coil embolization using a retrograde approach through the posterior circulation for wide-neck or branch-incorporated PcomA aneurysms. Retrograde stenting was successful without periprocedural complications. These aneurysms were completely occluded. The patency of the PcomA was maintained in all cases.

Endovascular treatment for ruptured and unruptured vertebral artery dissecting aneurysms: a meta-analysis

Background

Different endovascular modalities have been applied to the treatment of vertebral artery dissecting aneurysms, the most commonly used being internal trapping and stent-assisted coiling, although the ideal treatment remains controversial.

Objective

To perform a meta-analysis to study clinical outcomes of patients with vertebral artery dissecting aneurysms who were treated with internal trapping or stent-assisted coiling.

Materials and methods

We conducted a meta-analysis of eight retrospective studies that compared internal trapping with stent-assisted coiling for the treatment of vertebral artery dissecting aneurysms. The primary outcomes of this study were immediate occlusion, long-term occlusion, good outcome ratio, perioperative mortality, and angiographic recurrence. Subgroup analyses were conducted of patients with ruptured versus unruptured vertebral artery dissecting aneurysms.

Results

Eight studies comprising a total of 188 patients were included in the analysis. For ruptured cases, in comparison with stent-assisted coiling groups, the patients treated with trapping techniques had a higher rate of immediate postoperative occlusion (OR=0.165; 95% CI 0.067 to 0.405; p<0.01), although there was no significant difference in long-term occlusion (OR=1.059; 95% CI 0.033 to 34.121; p=0.974), good clinical outcome rates, recurrence rates, and perioperative mortality. For unruptured cases, patients in the trapping groups also had higher immediate occlusion rates than those who underwent stent-assisted coiling (OR=0.175; 95% CI 0.043 to 0.709; p=0.015), while rates of both recurrence and good clinical outcome were similar between the two groups.

Conclusions

Both internal trapping and stent-assisted coiling are technically feasible for ruptured vertebral artery dissecting aneurysms, with high rates of good long-term neurologic outcomes and low recurrence and mortality rates. For unruptured aneurysms, conservative treatment is recommended. When a posterior inferior cerebellar artery (PICA) origin is involved, bypass surgery or vertebral artery-to-PICA stent placement plus coil embolization should be considered.

Therapeutic Progress in Treating Vertebral Dissecting Aneurysms Involving the Posterior Inferior Cerebellar Artery

Among the variations of vertebral artery dissecting aneurysms (VDAs), VDAs involving the posterior inferior cerebellar artery (PICA), especially ruptured and high-risk unruptured aneurysms, are the most difficult to treat. Because the PICA is an important structure, serious symptoms may occur after its occlusion. Retained PICAs are prone to re-bleeding because VDAs are difficult to completely occlude. There is therefore confusion regarding the appropriate treatment for VDAs involving the PICA. Here, we used the PubMed database to review recent research concerning VDAs that involve the PICA, and we found that treatments for VDAs involving the PICA include (i) endovascular treatment involving the reconstruction of blood vessels and blood flow, (ii) occluding the aneurysm using an internal coil trapping or an assisted bypass, (iii) inducing reversed blood flow by occluding the proximal VDA or forming an assisted bypass, or (iv) the reconstruction of blood flow via a craniotomy. Although the above methods effectively treat VDAs involving the PICA, each method is associated with both a high degree of risk and specific advantages and disadvantages. The core problem when treating VDAs involving the PICA is to retain the PICA while occluding the aneurysm. Therefore, the method is generally selected on a case-by-case basis according to the characteristics of the aneurysm. In this study, we summarize the various current methods that are used to treat VDAs involving the PICA and provide schematic diagrams as our conclusion. Because there is no special field of research concerning VDAs involving the PICA, these cases are hidden within many multiple-cases studies. Therefore, this study does not review all relevant documents and may have some limitations. Thus, we have focused on the mainstream treatments for VDAs that involve the PICA.

Intracranial-to-intracranial bypass for posterior inferior cerebellar artery aneurysms: options, technical challenges, and results in 35 patients

OBJECT Intracranial-to-intracranial (IC-IC) bypasses are alternatives to traditional extracranial-to-intracranial (EC-IC) bypasses to reanastomose parent arteries, reimplant efferent branches, revascularize branches with in situ donor arteries, and reconstruct bifurcations with interposition grafts that are entirely intracranial. These bypasses represent an evolution in bypass surgery from using scalp arteries and remote donor sites toward a more local and reconstructive approach. IC-IC bypass can be utilized preferentially when revascularization is needed in the management of complex aneurysms. Experiences using IC-IC bypass, as applied to posterior inferior cerebellar artery (PICA) aneurysms in 35 patients, were reviewed. METHODS Patients with PICA aneurysms and vertebral artery (VA) aneurysms involving the PICA's origin were identified from a prospectively maintained database of the Vascular Neurosurgery Service, and patients who underwent bypass procedures for PICA revascularization were included. RESULTS During a 17-year period in which 129 PICA aneurysms in 125 patients were treated microsurgically, 35 IC-IC bypasses were performed as part of PICA aneurysm management, including in situ p3-p3 PICA-PICA bypass in 11 patients (31%), PICA reimplantation in 9 patients (26%), reanastomosis in 14 patients (40%), and 1 V3 VA-to-PICA bypass with an interposition graft (3%). All aneurysms were completely or nearly completely obliterated, 94% of bypasses were patent, 77% of patients were improved or unchanged after treatment, and good outcomes (modified Rankin Scale ≤ 2) were observed in 76% of patients. Two patients died expectantly. Ischemic complications were limited to 2 patients in whom the bypasses occluded, and permanent lower cranial nerve morbidity was limited to 3 patients and did not compromise independent function in any of the patients. CONCLUSIONS PICA aneurysms receive the application of IC-IC bypass better than any other aneurysm, with nearly one-quarter of all PICA aneurysms treated microsurgically at our center requiring bypass without a single EC-IC bypass. The selection of PICA bypass is almost algorithmic: trapped aneurysms at the PICA origin or p1 segment are revascularized with a PICA-PICA bypass, with PICA reimplantation as an alternative; trapped p2 segment aneurysms are reanastomosed, bypassed in situ, or reimplanted; distal p3 segment aneurysms are reanastomosed or revascularized with a PICA-PICA bypass; and aneurysms of the p4 segment that are too distal for PICA-PICA bypass are reanastomosed. Interposition grafts are reserved for when these 3 primary options are unsuitable. A constructive approach that preserves the PICA with direct clipping or replaces flow with a bypass when sacrificed should remain an alternative to deconstructive PICA occlusion and endovascular coiling when complete aneurysm occlusion is unlikely.

Endovascular treatment of PICA aneurysms with a Low-profile Visualized Intraluminal Support (LVIS Jr) device

OBJECTIVE

To describe the treatment of posterior inferior cerebellar artery (PICA) aneurysms with the Low-profile Visualized Intraluminal Support Device (LVIS Jr) stent.

MATERIALS AND METHODS

The databases of three institutions were retrospectively reviewed. Patients who underwent endovascular treatment of PICA aneurysms using a reconstructive technique where the LVIS Jr stent was totally or partially deployed into the PICA were included in the analysis. Clinical presentation, aneurysm and PICA sizes, procedural complications, and clinical and angiographic follow-up information was recorded and analyzed.

RESULTS

Seven patients who underwent endovascular treatment of PICA aneurysms with an LVIS Jr stent were identified. Four aneurysms were treated in the acute phase of subarachnoid hemorrhage (SAH). There were no symptomatic complications. One patient had spasm distal to the stent as a result of mechanical straightening of the vessel. One patient was treated in the acute phase of SAH and required a gycoprotein IIb/IIIa inhibitor after the stent was implanted. This patient needed to be re-treated to complete embolization. All patients had good clinical outcomes (Glasgow Outcome Scale 5). No in-stent stenosis or occlusion was seen on short-term angiographic follow-up and the aneurysms were occluded.

CONCLUSIONS

This small series suggests that the use of a reconstructive technique with the LVIS Jr stent for the treatment of PICA aneurysms is feasible, safe and effective in the short term.

Endovascular Treatment of Vertebral Artery Dissecting Aneurysms That Cause Subarachnoid Hemorrhage : Consideration of Therapeutic Approaches Relevant to the Angioarchitecture

Objective

Intracranial ruptured vertebral artery dissecting aneurysms (VADAns) are associated with high morbidity and mortality when left untreated due to the high likelihood of rebleeding. The present study aimed to establish an endovascular therapeutic strategy that focuses specifically on the angioarchitecture of ruptured VADAns.

Methods

Twenty-three patients with ruptured VADAn received endovascular treatment (EVT) over 7 years. The patient group included 14 women (60.9%) and 9 men (39.1%) between the ages of 39 and 72 years (mean age 54.2 years). Clinical data and radiologic findings were retrospectively analyzed.

Results

Four patients had aneurysms on the dominant vertebral artery. Fourteen (61%) aneurysms were located distal to the posterior inferior cerebellar artery (PICA). Six (26%) patients had an extracranial origin of the PICA on the ruptured VA, and 2 patients (9%) had bilateral VADAns. Eighteen patients (78%) were treated with internal coil trapping. Two patients (9%) required an adjunctive bypass procedure. Seven patients (30%) required stent-supported endovascular procedures. Two patients experienced intra-procedural rupture during EVT, one of which was associated with a focal medullary infarction. Two patients (9%) exhibited recanalization of the VADAn during follow-up, which required additional coiling. No recurrent hemorrhage was observed during the follow-up period.

Conclusion

EVT of ruptured VADAns based on angioarchitecture is a feasible and effective armamentarium to prevent fatal hemorrhage recurrence with an acceptable low risk of procedural complications. Clinical outcomes depend mainly on the pre-procedural clinical state of the patient. Radiologic follow-up is necessary to prevent hemorrhage recurrence after EVT.

Management of hemorrhagic dissecting vertebral artery aneurysms involving posterior inferior artery

We reported 2 cases with hemorrhagic dissecting vertebral artery (VA) aneurysms involving posterior inferior cerebellar artery (PICA), and one was treated with aneurysm trapping and PICA-VA anastomosis, whereas another was treated with coil embolization and VA-to-PICA stent placement. We suggest both bypass surgery and VA-to-PICA stent placement are good options for PICA revascularization.

Stent-assisted coil embolization of aneurysms with small parent vessels: safety and efficacy analysis

BACKGROUND

Stent-assisted coil embolization (SACE) is a viable therapeutic approach for wide-neck intracranial aneurysms. However, it can be technically challenging in small cerebral vessels (≤2 mm).

OBJECTIVE

To present our experience with stents approved for SACE in aneurysms with small parent arteries.

METHODS

All patients who underwent stent-assisted aneurysm treatment with either a Neuroform or an Enterprise stent device at our institution between June 2006 and October 2012 were identified. Additionally, we evaluated each patient's vascular risk factors, aneurysm characteristics (ruptured vs non-ruptured, incidental finding, recanalized) and follow-up angiography data.

RESULTS

A total of 41 patients with 44 aneurysms met our criteria, including 31 women and 10 men. Most of the aneurysms were located in the anterior circulation (75%). Stent placement in vessels 1.2-2 mm in diameter was successful in 93.2%. Thromboembolic complications occurred in 6 cases and vessel straightening was seen in 1 case only. Initial nearly complete to complete aneurysm obliteration was achieved in 88.6%. Six-month follow-up angiography showed coil compaction in three cases, one asymptomatic in-stent stenosis and stent occlusion. Twelve to 20-months' follow-up showed stable coil compaction in two patients compared with previous follow-up, and aneurysm recanalization in two patients. Twenty-four to 36-months' follow-up showed further coil compaction in one of these patients and aneurysm recanalization in a previous case of stable coil compaction on mid-term follow-up.

CONCLUSIONS

Our results suggest that SACE of aneurysms with small parent vessels is feasible in selected cases and shows good long-term patency rates of parent arteries.

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

BACKGROUND

Vertebral artery (VA) aneurysms comprise approximately one-third of posterior circulation aneurysms. They are morphologically variable, and located critically close to the cranial nerves and the brainstem. We aim to represent the characteristics of these aneurysms and their treatment, and to analyze the outcome.

METHODS

We reviewed retrospectively 9709 patients with intracranial aneurysms. Of these, we included 190 with aneurysms at the VA or VA-posterior inferior cerebellar artery junction. These patients were treated in the Department of Neurosurgery, Helsinki, Finland, between 1934 and 2011.

RESULTS

The 190 patients had 193 VA aneurysms, among which 131 (68%) were ruptured. The VA aneurysm caused a mass effect in 7 and ischemia in 2 patients. Compared to 4387 patients with a ruptured aneurysm in other locations, those with a VA aneurysm were older, their aneurysms were more often fusiform, and more often caused intraventricular hemorrhages. Among surgically treated aneurysms, clipping was the treatment in 91 (88%) saccular and 11 (50%) fusiform aneurysms. Treatment was endovascular in 13 (9%), and multimodal in 6 (4%) aneurysms. Within a year after aneurysm diagnosis, 53 (28%) patients died. Among the survivors, 104 (93%) returned to an independent or to their previous state of life; only 2 (2%) were unable to return home.

CONCLUSIONS

Microsurgery is a feasible treatment for VA aneurysms, although cranial nerve deficits are more common than in endovascular surgery. Despite the challenge of an often severe hemorrhage, of challenging morphology, and risk for laryngeal palsy, most patients surviving the initial stage return to normalcy.

Preliminary experience with self-expanding closed-cell stent placement in small arteries less than 2 mm in diameter for the treatment of intracranial aneurysms

OBJECT

The purpose of this study was to report the authors' preliminary experience using self-expanding closed-cell stents deployed in small arteries (< 2 mm in diameter) to treat intracranial aneurysms.

METHODS

A total of 31 patients were studied. All subjects met the following criteria: 1) they received an Enterprise stent for treatment of a wide-necked aneurysm or a dissecting aneurysm or as part of a stent-salvage procedure; and 2) they had an Enterprise stent deployed in a small parent artery (< 2 mm in diameter) that had no atherosclerotic stenosis. Procedure-related complications and follow-up sizes of the parent arteries were evaluated for safety and patency.

RESULTS

There were 16 ruptured aneurysms and 15 unruptured aneurysms. Three (9.7%) of the 31 patients experienced procedure-related complications, and they all were asymptomatic. Follow-up angiography was performed in 27 patients (87.1%) (at a mean 15.5 months after surgery). Parent arteries with 2 acute angles (n = 4) were occluded in 3 cases (75.0%), and those with no acute angles (n = 13) or 1 acute angle (n = 6) showed 100% patency on follow-up angiography. There was a significant difference between the follow-up sizes (mean 1.72 ± 0.30 mm) of parent arteries and their sizes (mean 1.59 ± 0.26 mm) before treatment (95% CI - 0.254 to - 0.009 mm; p = 0.037, paired-samples t-test).

CONCLUSIONS

In the current series the deployment of self-expanding closed-cell stents in small arteries was safe and resulted in good patency, especially when the stents were deployed in segments of the parent artery with no acute angles or only 1 acute angle.

Treatment of ruptured vertebral artery dissecting aneurysms distal to the posterior inferior cerebellar artery: stenting or trapping?

PURPOSE

The treatment of ruptured vertebral artery dissecting aneurysms (VADAs) continues to be controversial. Our goal was to evaluate the safety, efficacy, and long-term outcomes of internal trapping and stent-assisted coiling (SAC) for ruptured VADAs distal to the posterior inferior cerebellar artery (supra-PICA VADAs), which is the most common subset.

METHODS

A retrospective review was conducted of 39 consecutive ruptured supra-PICA VADAs treated with internal trapping (n = 20) or with SAC (n = 19) at our institution. The clinical and angiographic data were retrospectively compared.

RESULTS

The immediate total occlusion rate of the VADAs was 80 % in the trapping group, which improved to 88.9 % at the follow-ups (45 months on average). Unwanted occlusions of the posterior inferior cerebellar artery (PICA) were detected in three trapped cases. Incomplete obliteration of the VADA or unwanted occlusions of the PICA were detected primarily in the VADAs closest to the PICA. In the stenting group, the immediate total occlusion rate was 47.4 %, which improved to 100 % at the follow-ups (39 months on average). The immediate total occlusion rate of the VADAs was higher in the trapping group (p < 0.05), but the later total occlusion was slightly higher in the stenting group (p > 0.05).

CONCLUSIONS

Our preliminary results showed that internal trapping and stent-assisted coiling are both technically feasible for treating ruptured supra-PICA VADAs. Although not statistically significant, procedural related complications occurred more frequently in the trapping group. When the VADAs are close to the PICA, we suggest that the lesions should be treated using SAC.

Using the snare system to cross the acute-angled vertebrobasilar junction in treating posterior inferior cerebellar artery aneurysm with the stent-assisted method via a retrograde approach. A technical note

Retrograde stenting via the contralateral vertebral artery (VA) is a safe and effective treatment for posterior inferior cerebellar artery (PICA) aneurysm. Many methods, including tip shaping and the looping technique, have been attempted as ways to cross the vertebrobasilar (VB) junction. Here, we introduce an alternative method using a Snare system to overcome the acute-angled VB junction after repeated failures using other techniques. The Snare system was navigated to the proximal basilar artery via the ipsilateral VA. A guidewire was introduced in the contralateral VA and gently advanced to the basilar artery in order to pass through the loop of the Snare system. Following this, the Snare system caught the guidewire and it was very carefully pulled down to the ipsilateral VA crossing the VB junction. We suggest this technique as a method to cross the acute-angled VB junction after failure of all other attempts to overcome this challenge.

Flow-diverter stent for the treatment of a non-origin posterior inferior cerebellar artery aneurysm. A case report

We describe the case of a 44-year old man with a ruptured wide-necked non-origin aneurysm of the posterior inferior cerebellar artery successfully treated with placement of a low porosity stent. To our knowledge, there are no cases in the literature of a non-origin posterior inferior cerebellar artery aneurysm treated with a flow-diverter stent.

Treatment of ruptured vertebral artery dissecting aneurysms. A short report

We evaluated the outcomes of endovascular or surgical treatment of ruptured vertebral artery dissecting aneurysms (VADAs), and investigated the relations between treatment complications and the development and location of the posterior inferior cerebellar artery (PICA). We treated 14 patients (12 men, two women; mean age, 56.2 years) with ruptured VADAs between March 1999 and June 2012 at our hospital. Six and eight patients had Hunt and Hess grades 1-3 and 4-5, respectively. Twelve patients underwent internal endovascular trapping, one underwent proximal endovascular occlusion alone, and one underwent proximal endovascular occlusion in the acute stage and occipital artery (OA)-PICA anastomosis and surgical trapping in the chronic stage. The types of VADA based on their location relative to the ipsilateral PICA were distal, PICA-involved, and non-PICA in nine, two, and three patients, respectively. The types of PICA based on their development and location were bilateral anterior inferior cerebellar artery (AICA)-PICA, ipsilateral AICA-PICA, extradural, and intradural type in one, two, two, and nine patients, respectively. Two patients with high anatomical risk developed medullary infarction, but their midterm outcomes were better than in previous reports. The modified Rankin scale indicated grades 0-2, 3-5, and 6 in eight, three, and three patients, respectively. A good outcome is often obtained in the treatment of ruptured VADA using internal endovascular trapping, except in the PICA-involved type, even with high-grade subarachnoid hemorrhage. Treatment of the PICA-involved type is controversial. The anatomical location and development of PICA may be predicted by complications with postoperative medullary infarction.

Stent placement to treat ruptured vertebral dissecting aneurysms

Conventional endovascular treatment may have limitations for vertebral dissecting aneurysm involving the origin of the posterior inferior cerebellar artery (PICA). We report our experiences of treating vertebral dissecting aneurysm with PICA origin involvement by placing a stent from the distal vertebral artery (VA) to the PICA to save the patency of the PICA. Stenting from the distal VA to the PICA was attempted to treat ruptured VA dissecting aneurysm involving the PICA origin with sufficient contralateral VA in eight patients. The procedure was successfully performed in seven patients with one failure because of PICA origin stenosis, which was treated with two overlapping stents. In the seven patients, PICAs had good patency on postoperative angiography and transient lateral brainstem ischemia represents a procedure-related complication. Follow-up angiographies were performed in seven patients and showed recanalization of the distal VA in three patients without evidence of aneurysmal filling. There was no evidence of aneurysm rupture during the follow-up period, and eight patients had favorable outcomes (mRS, 0 - 1). Placing a stent from the distal VA to the PICA with VA occlusion may present an alternative to conventional endovascular treatment for vertebral dissecting aneurysm with PICA origin involvement with sufficient contralateral VA.

Reconstructive Treatment of Ruptured Intracranial Spontaneous Vertebral Artery Dissection Aneurysms: Long-Term Results and Predictors of Unfavorable Outcomes

Introduction

Few studies focused on predictors of unfavorable outcomes (modified Rankin Scale, 2–6) after reconstructive treatment of the ruptured intracranial spontaneous vertebral artery dissection aneurysms (ris-VADAs), which was evaluated based on 57 reconstructed lesions in this study.

Methods

Results of 57 consecutive patients (M:F = 29∶28; median age, 48 years; range, 27 to 69 years) harboring 57 ris-VADAs, which were treated with coils combined with single stent(n = 32), double overlapping stents (n = 16), and triple overlapping stents (n = 9) between October 2000 to March 2011, were retrospectively reviewed and analyzed.

Results

The available (n = 54) mean durations of angiographic and clinical follow-ups were 27 months (range, 12 to 78) and 62 months (range, 12 to 132), respectively. The involvement of PICA (p = 0.004), size of lesions (p = 0.000), quantity of stent (p = 0.001), and coil type (p = 0.002) affected the immediate obliteration grade, which was only risk factor for angiographic recurrences (p = 0.031). Although the post-treatment outcomes did not differ between single stent and multiple stents (p = 0.434), 5 angiographic recurrences, 1 rebleeding and 1 suspected rebleeding, all occurred in partial obliteration after single-stent-assisted coiling. Progressive thrombosis and in-stent obliteration were not detected on follow-up angiograms. Older age (odds ratio [OR] = 1.090; 95% confidence interval [CI], 1.004–1.184; p = 0.040) and unfavorable Hunt-Hess scale (OR = 4.289; 95%CI, 1.232–14.933; p = 0.022) were independent predictors of unfavorable outcomes in the reconstructed ris-VADAs.

Conclusions

Immediate obliteration grade was only risk factor for angiographic recurrence after reconstructive treatment. Unfavorable Hunt-Hess grade and older age were independent predictors of unfavorable outcomes in ris-VADAs.

Stent-assisted coil embolization of posterior communicating artery aneurysms

BACKGROUND AND PURPOSE

Use of protective stents may not be effective in coil embolization of wide-neck aneurysms involving the posterior communicating artery. Successful implementation depends on the caliber of the vessel, its angle of origin, and the manner in which its orifice is incorporated into the aneurysm. Presented here are the results (clinical and radiographic) of coil embolization in aneurysms of the ICA-posterior communicating artery junction, variably aided by stents. The primary focus is angiographic configurations that impact stent placement.

MATERIALS AND METHODS

From a prospective data repository, we retrieved records of 32 consecutive patients with 33 posterior communicating artery aneurysms, all of which were treated by stent-assisted coil embolization between June 2008 and August 2012. Outcomes were analyzed in terms of aneurysm configuration and clinical status.

RESULTS

Stents were positioned entirely in the ICA (n = 26), from the ICA to the posterior communicating artery (n = 2), in the posterior communicating artery only (n = 3), and retrograde from the posterior communicating artery to the ICA terminus (n = 2). Procedure-related complications occurred in 3 patients (9.1%), but only 1 (3.0%) had mild neurologic sequelae (Glasgow Outcome Score 4). Using coil embolization, we achieved successful occlusion in 24 aneurysms (72.7%), and in 9 others, subtotal occlusion was conferred. During a mean follow-up of 15.7 ± 10.7 months, imaging of 27 aneurysms documented stable occlusion in 19 (70.4%), whereas angiography of 15 aneurysms (39.5%) disclosed 2 instances of in-stent stenosis (13.3%) and a solitary occurrence of stent migration (6.7%).

CONCLUSIONS

In posterior communicating artery aneurysms, stent protection during coil embolization is feasible by adjusting the procedural strategy to accommodate differing configurations of the aneurysm and its vascular source.

Wingspan Stenting for Intracranial Atherosclerotic Stenosis

BACKGROUND:

Intracranial atherosclerotic stenosis (ICAS) is responsible for 9% to 37% of ischemic strokes.

OBJECTIVE:

To evaluate the clinical outcome and risk factors for in-stent restenosis (ISR) after treatment of ICAS with a Wingspan stent.

METHODS:

Seventy-seven patients with 79 total target ICAS &gt; 60% (mean, 79.9 ± 8.4%; symptomatic ICAS, 96.2%) underwent attempted treatment with Wingspan stenting between March 2010 and March 2011. A retrospective review of the prospectively registered data was conducted to assess the risk factors for ISR and the clinical outcomes of these patients.

RESULTS:

The 30-day transient ischemic attack/stroke and death rates were 5.3% (95% confidence interval [CI], 0.1-10.5) and 0%, respectively. All patients but 1 were followed up clinically for a mean of 18.9 months (range, 12–23 months). During the period, cumulative transient ischemic attack/stroke and death rates were 8.1% (95% CI, 1.7-14.5) and 0%, respectively. Only 1 patient suffered a disabling stroke (subarachnoid hemorrhage), which was associated with retreatment of an ISR with a drug-eluting balloon-expandable stent. Follow-up angiography was available in 69 treated vessels (89.6%) at 3 to 24 months (median, 12 months). Binary ISR rate was 24.6%, of which 17.6% (3 of 17 cases) was symptomatic. Rapid balloon inflation (95% CI, 5.490-530.817) and longer length of stenosis (95% CI, 1.093-1.891) were independent risk factors for ISR.

CONCLUSION:

Wingspan stenting may be effective for appropriately selected ICAS patients. Rapid balloon inflation and longer lengths of stenosis were independent risk factors for ISR.