Vascular reconstruction related to the extracranial vertebral artery: the presentation of the concept and the basis for the establishment of the bypass system

The intracranial vertebrobasilar artery system has a unique hemodynamic pattern (vessel trunk converged bilateral flow with three groups of perforators directly arising from it), is embedded within intense osseous constraints, and is located far from conventional donor vessels. Two major traditional modalities of posterior circulation revascularization encompass the superficial temporal artery to the superior cerebellar artery and the occipital artery to the posteroinferior cerebellar artery anastomosis, which are extracranial-intracranial low-flow bypass with donor arteries belonging to the anterior circulation and mainly supply focal perforators and distal vascular territories. As our understanding of flow hemodynamics has improved, the extracranial vertebral artery-related bypass has further evolved to improve the cerebral revascularization system. In this article, we propose the concept of "vascular reconstruction related to the extracranial vertebral artery" and review the design philosophy of the available innovative modalities in the respective segments. V1 transposition overcomes the issue of high rates of in-stent restenosis and provides a durable complementary alternative to endovascular treatment. V2 bypass serves as an extracranial communication pathway between the anterior and posterior circulation, providing the advantages of high-flow, short interposition grafts, orthograde flow in the vertebrobasilar system, and avoiding complex skull base manipulation. V3 bypass is characterized by profound and simultaneous vascular reconstruction of the posterior circulation, which is achieved by intracranial-intracranial or multiple bypasses in conjunction with skull base techniques. These posterior circulation vessels not only play a pivotal role in the bypass modalities designed for vertebrobasilar lesions but can also be implemented to revascularize the anterior circulation, thereby becoming a systematic methodology.

Is revascularization of V1 Segment of vertebral artery combined with Ipsilateral carotid endarterectomy safe?

BACKGROUND

The recommendation of the European Society for Vascular Surgery (ESVS) is vertebral revascularization combined with Ipsilateral CEA (carotid endarterectomy)should not be performed in the same operation. ESVS believes that vertebral revascularization combined with Ipsilateral CEA increases perioperative death/stroke rates. In our opinion, revascularization of the first segment of vertebral artery (V1) combined with Ipsilateral CEA is safe compared with vertebral V1 revascularization in the perioperative period.

OBJECTIVE

The purpose of this study is to prove revascularization of V1 Segment of vertebral artery combined with Ipsilateral CEA is secure in the perioperative period.

METHODS

We describe our experience with homochronous revascularization of V1 Segment of vertebral artery with Ipsilateral CEA (group B) and simple revascularization of V1 Segment of vertebral artery (group A) in 48 consecutive patients during a 5-year period. O.Y.(Ouyang) incisions were used in both groups. Compare the results of the two procedures with aspects of mortality, stroke, morbidity, incident rates of complications, and so on.

RESULTS

There was no significant difference between patients in group A and group B in terms of red blood cell reduction, postoperative ventilator using time, postoperative drainage volume, postoperative drainage days, postoperative hospitalize duration, and incident rates of postoperative complications. The postoperative complications include death，stroke, Horner syndrome, Vocal paralysis, Hypoglossal nerve paralysis, Wound hematomas and Lymphatic leakage.

CONCLUSION

Revascularization of vertebral artery combined with Ipsilateral CEA should be divided into revascularization of V1 Segment of vertebral artery combined with Ipsilateral CEA and revascularization of V3 Segment of vertebral artery with Ipsilateral CEA. Revascularization of V1 Segment of vertebral artery combined with Ipsilateral CEA is safe, it can be performed for suitable patients who are fit for indications. O.Y.(Ouyang) incisions can fully expose the target blood vessels and simplify the procedures without transecting the sternocleidomastoid muscles in operations.

Transposition of Anomalous Left Vertebral to Carotid Artery During the Management of Thoracic Aortic Dissections and Aneurysms

OBJECTIVES

Preservation of antegrade flow to the left vertebral artery is often achieved by transposition or bypass to the left subclavian artery during zone 2 thoracic endovascular aortic repair (TEVAR). An anomalous left vertebral artery (aLVA) originating directly from the aortic arch is a common arch variant with a reported incidence of 4-6%. In addition, 6-10% of vertebral arteries terminate in a posterior inferior cerebellar artery (PICA), increasing the risk of stroke if not revascularized. Few series of aLVA to carotid transposition have been reported. The aim of this study was to evaluate the outcomes of patients who underwent aLVA to carotid transposition for the management of aortic disease.

METHODS

A retrospective review of all aLVA-carotid transpositions performed for the management of thoracic aortic dissection or aneurysm at a single center from 2018 to 2021 was performed. The primary outcomes were postoperative stroke and patency of the transposed aLVA. Secondary outcomes were spinal cord ischemia, postoperative cranial nerve injury (CNI), and Horner's syndrome.

RESULTS

Seventeen patients underwent aLVA to carotid transposition as an adjunct to management of aortic disease during the study period. Most were men (14) and the mean age was 54 (±16 years). The primary indication for aortic repair was dissection in 10, aneurysm in 6, and Kommerell diverticulum in 1. Nine patients underwent zone 2 TEVAR, seven received open total arch repair and there was one attempted total endovascular arch repair which was aborted due to unfavorable anatomy. Twelve transpositions were performed prior to or concomitant with planned aortic repair due to high-risk cerebrovascular anatomy (3 PICA termination, 6 dominant aLVA, 4 intracranial left vertebral artery stenosis), and two were performed postoperatively for treatment of type II endoleak. LVA diameter ranged from 2 - 6mm (mean 3.3 mm). Mean operative time for transposition was 178 (±38) minutes, inclusive of left subclavian artery revascularization and mean estimated blood loss was 169 (±188) mL. No patients experienced 30-day postoperative spinal cord ischemia, stroke, or mortality. There were two cases of postoperative hoarseness, presumably due to recurrent laryngeal nerve palsy, both of which resolved within 4 months. There were no cases of Horner's syndrome. At follow-up (mean 306 days [6-714 days]), all transpositions were patent.

CONCLUSIONS

Vertebral-carotid transposition is a safe and effective adjunct in the management of aortic disease with anomalous origin of the LVA.

Hybrid Recanalization for the Treatment of Carotid/Vertebral In-stent Restenosis or Occlusion: Pilot Surgery Experiences From One Single Center

Background : The hybrid recanalization of internal carotid artery (ICA) and vertebral artery (VA) in-stent restenosis or occlusion using a combination of endarterectomy and endovascular intervention has achieved technical success. We present our surgical experiences to further evaluate the safety and efficacy of the hybrid technique for the treatment of in-stent restenosis and occlusion. Methods : A cohort of 12 refractory patients with in-stent restenosis or occlusion who underwent hybrid recanalization, a combination of endarterectomy and endovascular intervention, were retrospectively analyzed. Medical records, including presenting symptoms, comorbidities, contralateral ICA/VA findings, use of antiplatelet drugs, postoperative complications, and angiographic outcomes, were collected. Results : Among 415 consecutive patients with ICA, common carotid artery, and V1 segment lesions, 12 refractory patients (2.89%) with 13 cases were enrolled in our study (1 female and 11 male). All patients underwent successful hybrid recanalization. There were no cases of postoperative stroke or death. Only two patients sustained hoarseness, but it resolved within 2 weeks after surgery. Three patients were treated with dual antiplatelet (aspirin and clopidogrel), seven with single antiplatelet (aspirin), one with single antiplatelet (clopidogrel), and one with single antiplatelet (ticagrelor). All patients were followed up in the outpatient department according to the protocol, with a mean follow-up period of 13 months (range, 6-24 months). No death or recurrent symptoms occurred during the regular follow-up period. Conclusion : The hybrid technique maybe a safe and feasible treatment option to recanalize in-stent restenosis or occlusion with acceptable complications.

Minimally Invasive Surgical Repair of Vertebral Artery Ostium Stenosis in Patients with Ischemic Stroke: A Single-Center Case Series

BACKGROUND

Ischemic stroke is the second leading cause of death in North Macedonia. Posterior circulation disease, caused by vertebral artery (VA) ostium (VAo) stenosis, is a common cause of ischemic stroke. We established a treatment approach using surgical revascularization of posterior circulation disease. In the present observational study, we assessed the outcome after surgical revascularization of the posterior circulation ischemia caused by VAo stenosis.

METHODS

A retrospective analysis of 20 consecutive patients who had undergone surgery from January 2017 to December 2019. The VA was accessed through a 3-cm incision in the upper medial clavicle. The corrective procedures consisted of resection and anastomosis (15 of 20), VA to subclavian artery transposition (16 of 20), endarterectomy (10 of 20), vein graft interposition techniques (4 of 20), and vein graft bypass (1 of 20).

RESULTS

The cohort included 9 acute cases. The mean patient age was 66.5 years (range 46-77). Of the 20 patients, 8 were women and 12 were men. Left-sided VA pathology was present in 75% of the cases. We observed rapid clinical improvement in 19 patients (95%). The total study period was 321 patient-months, with a median follow-up of 18 months (interquartile range, 5-24 months). One patient had died of an unknown cause after 12 months. During the follow-up period, 15 patients (75%) had reported permanent clinical improvement with no significant relapse of symptoms.

CONCLUSIONS

Minimally invasive surgical revascularization of the posterior brain circulation is a clinically effective therapeutic approach to manage ischemia caused by VAo stenosis. It can be performed safely, promote long-lasting symptom relief, and prevent recurrent strokes.

Left Vertebral Artery to Common Carotid Artery Transposition in a Patient With Bilateral Vertebral Insufficiency: 3-Dimensional Operative Video

Extracranial vertebral artery (VA) atherosclerosis is responsible for 14% to 32% of posterior circulation infarctions.1 In the posterior circulation, narrowing of the VA > 30% is significantly associated with strokes. Subclavian artery (SCA) atherosclerosis can produce subclavian steal. Retrograde VA flow around an occluded SCA decreases blood flow to the posterior circulation and causes vertebrobasilar insufficiency (VBI). Flow augmentation to the posterior circulation can be achieved by VA endarterectomy, arterial stenting, VA-common carotid artery (CCA) transposition, or bypass using an interposition graft.2,3 This video illustrates microsurgical revascularization of the proximal VA with VA-CCA transposition. A 58-yr-old man with a prior stroke and chronic right VA occlusion presented with dysarthria and gait instability. Angiographic evaluation confirmed complete midcervical right VA occlusion and left SCA occlusion proximal to VA origin, with subclavian steal. After obtaining patient consent and a failed attempt at endovascular recanalization of the left SCA, a left VA-CCA end-to-side transposition was performed. Neck dissection exposed the left CCA. The thyrocervical trunk served as a landmark to identify the SCA, which was traced proximally to the VA origin. After proximal occlusion, the VA was transected and "fish-mouthed" for end-to-side anastomosis to CCA. An intraluminal, continuous suture technique was used to sew the back walls of this anastomosis. Postoperative computed tomography angiography confirmed bypass patency. Collateral circulation through the thyrocervical and costocervical trunks likely supplied the left arm, and no cerebral, or limb, ischemic symptoms were noted on follow-up. VA-CCA transposition is an uncommon technique for safe and effective revascularization of symptomatic, medically refractory VBI caused by VA occlusion or, as in this case, SCA occlusion with secondary subclavian steal. Used with permission from Barrow Neurological Institute, Phoenix, Arizona.

Surgical Treatment of Vertebral Artery Stenosis: An Overlooked Surgery with Low Morbidity

BACKGROUND

Vertebral artery (VA) stenosis as a cause of ischemic events and its surgical treatment is an overlooked subject. After reporting our initial results, the results of VA stenosis operations and the follow-up studies are analyzed.

MATERIAL AND METHODS

This retrospective, single-center study includes 43 symptomatic proximal VA stenosis patients between September 2012 and March 2019. The demographics and clinical data were obtained from the hospital records. Doppler ultrasonography and computed tomography angiography were used to establish the diagnosis and for follow-up. The surgical procedures were as follows: VA transposition in 30 (69.8%), VA bypass 8 (18.6%), saphenous vein interposition in VA in 4 (9.3%), and decompression of kinking in 1 (2.3%) patient. Eleven patients (25.5%) had concomitant carotid surgery. The Kaplan-Meier method was used to calculate the survival and patency rates.

RESULTS

Most common symptoms were vertigo and loss of balance in 38 (88.4%) and 14 (32.6%) patients, respectively. Twenty-five patients were males (58.1%), and the average age was 64.6 ± 9.8 (50-90) years. The 30-day death, 30-day stroke, and 30-day death/stroke rates were 2.3%, 4.7%, and 7%, respectively. Ten patients (23.3%) had morbidities which were related to the intervention. Horner syndrome was found in 5 (11.6%) patients, and facial nerve injury was found in one (2.3%) patient. Three (7.1%) patients died during the follow-up period, and overall survival of the patients at 3 years was 91.4% ± 5.8%. Two (4.7%) patients had cerebrovascular events (CVEs) occurred during the follow-up. One- and three-year CVE-free survivals were 97.1% ± 2.9% and 90.1% ± 7.2%, respectively. Two patients (5.4%) had restenosis. One- and three-year patency of VA after procedure was 89.1% ± 7.4%. Thirty-seven (86%) patients had complete recovery of symptoms after surgery; 5 patients (11.6%) kept their preoperative symptoms in different levels.

CONCLUSIONS

Vertebral artery surgery can be performed with acceptable mortality and morbidity rates. Restenosis-free, CVE-free, and overall survival rates are satisfactory.

Safety and Blood-Flow Outcomes for Hybrid Recanalization in Symptomatic Refractory Long-Segmental Vertebral Artery Occlusion-Results of a Pilot Study

Objective: Hybrid recanalization for vertebral artery (VA) long-segmental occlusion using a combination of ostial vertebral endarterectomy and distal endovascular stenting has achieved technical success. The safety and efficacy of the hybrid technique should be further evaluated.

Methods: We examined a cohort of refractory patients with long-segmental occlusion in the VA and low flow in the basilar artery (BA). The hybrid technique was performed to achieve the recanalization of VA. Angiograms were analyzed for occlusive length, contralateral VA status and collaterals. Clinical variables, including 30-days outcomes and blood-flow changes within 6 months based on quantitative magnetic resonance angiography (qMRA) with non-invasive optimal vessel analysis (NOVA), were collected pre- and post-operatively.

Results: Among 290 consecutive cases with VA initial segment stenosis or occlusion, 14 patients (13 male and 1 female) with symptomatic long-segmental VA occlusion and low flow in the BA were refractory to the best standard medical therapy. The hybrid technique was successful in obtaining recanalization in all but one patient. The mean follow-up period was 17.2 ± 9.2 months. One patient had new ischemic deficits within seven days of the operation. Four patients suffered from transient Horner syndrome postoperatively, but had recovered completely by the 6-months follow-up. Within this period, all revascularization was visible with computed tomography angiography (CTA), and the blood-flow in the BA improved significantly (66.4 ± 15.3 ml/min vs. 104.0±12.9 ml/min, P < 0.05) within 6 months. No ischemic events recurred during follow-up.

Conclusions: The hybrid technique is potentially a safe and feasible method to achieve recanalization and improve hemodynamic compromise for long-segmental VA occlusion.

Internal Thoracic Artery to Vertebral Artery Bypass Surgery: A Cadaveric Feasibility Study

OBJECTIVE

Posterior circulation strokes account for over one quarter of all ischemic strokes. The frequency of vertebral artery origin stenosis (VAOS) in patients with vertebrobasilar insufficiency (VBI) has been estimated to be as high 26%-32%, and VAOS is the direct cause of posterior circulation strokes in 9% of patients. This association could have a significant genetic component. This study examines the feasibility of the internal thoracic artery (ITA) as a donor vessel for revascularization in patients with VAOS.

METHODS

Ten sides from 5 fresh-frozen white cadaveric necks derived from 3 women and 2 men were used in this study. The mean age of the cadavers at death was 77.2 years (range, 68-88 years). The subclavian artery, vertebral artery, and ITA were dissected. The length and diameter (proximal and distal) of the V1 segment and the length and diameter of the ITA were recorded. Finally, the ITA was transposed to the V1 segment of the vertebral artery (VA1).

RESULTS

The mean length of the VA1 and its diameter at the proximal and distal parts were 35.51 and 3.69 mm, respectively. The mean length and diameter of the ITA were 26.53 and 3.27 mm, respectively. Rerouting the ITA to the VA1 was feasible without tension on all sides.

CONCLUSIONS

This study indicates that the ITA is anatomically and hemodynamically an excellent option for bypass surgery in a VAOS scenario. We present convincing and reproducible data to aid neurosurgeons in choosing the procedure best suited to their patients.

Stent-Assisted Coiling of Pseudoaneurysm After Vertebro-Carotid Transposition: Harmonious Combination of Open and Endovascular Neurosurgical Techniques

BACKGROUND

Most cases of vertebral artery stenosis are treated either conservatively or surgically. When non-conservative treatment is chosen, whether to treat it with open surgery or endovascular intervention remains a topic of divergence. In the setting of endovascular therapy failure, the vertebral to common carotid artery transposition certainly is an appropriate choice to recover the posterior circulation. Like any other open surgery, it is not devoid of soft-tissue-related complications. A pseudoaneurysm following this procedure and at this particular location is a rare but lethal complication and, to the best of our knowledge, has not yet been reported.

CASE DESCRIPTION

We present the case of an 80-year-old man with previous ischemic stroke who presented to the emergency department with aphasia, right-sided weakness, and dysarthria. Invasive imaging revealed right vertebral stenosis and hypoplastic left vertebral artery that failed endovascular therapy. The patient was then treated with a right vertebral to common carotid artery transposition. During follow-up, a pseudoaneurysm was found and treated with a stent-assisted coiling.

CONCLUSIONS

Pseudoaneurysms at the extracranial carotid and vertebral circulation are rare and have potential for deadly outcomes. Despite several treatments available, this anatomical location requires endovascular therapy due to efficacy and promptitude of this treatment. This is an interesting case where the patient's management required open and endovascular procedures. The pseudoaneurysm was a rare complication that, to the best of our knowledge, has not previously been reported. This case is an illustration of complementary work between open surgery and endovascular intervention.

Occipital Artery to Extradural Vertebral Artery Bypass for Posterior Circulation Ischemia

BACKGROUND

Posterior circulation ischemic strokes can have devastating consequences, despite medical therapies. Extracranial–intracranial bypass for the augmentation of flow is a treatment option for selected patients with hemodynamic compromise and recurrent ischemia. However, posterior circulation bypass carries a higher risk and lower patency rate than bypass with anterior circulation.

OBJECTIVE

To present the occipital artery to the extradural vertebral artery (OA-eVA) bypass for posterior circulation ischemia.

METHODS

We retrospectively reviewed our experience of the OA-eVA bypass surgery in the treatment of bilateral vertebral steno-occlusive disease.

RESULTS

Seventeen patients were identified. Thirteen patients had bilateral vertebral artery (VA) occlusion (type I), while 4 patients had VA occlusion with contralateral VA severe stenosis (type II). All patients had cerebellar or pons infarction, for which the postoperative bypass patency rate was 100%, with carotid angiogram demonstrating excellent filling of the rostral basilar system or the posterior inferior cerebellar artery territory. The long-term follow-up outcome was favorable (modified Rankin score of 0-2) in 82% of patients (7 patients had complete resolution and 7 had improvement of symptoms) and unfavorable in 18%. One type II case without previous endovascular therapy developed recurrent ischemic onset associated with bypass occlusion.

CONCLUSION

OA-eVA bypass is a minimally invasive and effective alternative to posterior circulation ischemia. It provides sufficient blood flow augmentation to the vertebrobasilar territory. The advantages of this novel therapeutic strategy include avoiding performing craniotomy and deep bypass and achieving shorter operative times compared to conventional bypass surgery.

Experience with vertebral artery origin stenting and ostium dilatation: results of treatment and clinical outcomes

Background

The vertebral artery (VA) ostium (VAO) is a common stenosis site. Most patients with VAO stenosis refractory to medical treatment are treated endovascularly using stenting. To optimally cover the ostial plaque, which frequently extends into the adjacent subclavian artery, part of the stent must overhang in the subclavian artery. This configuration makes subsequent VA access very challenging in cases of in-stent or distal vertebrobasilar pathology; it also obstructs the distal subclavian artery.

Objective

To determine whether angioplasty at the ostium with a dual balloon (Flash Ostial) specially designed to allow the subclavian end of the stent to flare might circumvent these problems and, most importantly, provide optimal plaque coverage around the vertebral ostium.

Methods

Between June 2012 and July 2014, 11 patients with symptomatic VAO stenosis refractory to best medical therapy were treated with stenting and dual balloon Flash angioplasty. Demographics, results, and outcomes were reviewed.

Results

A total of 12 VAO stenting–dual balloon angioplasty procedures were performed (mean stenosis, 83.6%; range, 78–90%). Nine patients had mild-to-moderate (40–60%) contralateral VAO stenosis. The initial average modified Rankin Scale (mRS) score was 1.25. In all cases, immediate postangioplasty angiography showed excellent stent apposition against the VA and around the ostium in the subclavian artery. No permanent perioperative complications or deaths occurred. At a mean follow-up of 10.8 months (range 2–24), all patients had symptom resolution and no evidence of symptomatic restenosis on neuroimaging/Doppler studies; the average mRS score was 0.66. Three patients continued to have previously diagnosed mid-cervical VA stenosis; one of them had postprocedure dissection and an asymptomatic in-stent stenosis at 8 months.

Conclusions

Safety and feasibility were demonstrated using the Ostial Flash system for VAO stenting and angioplasty. No permanent perioperative complications were seen.

Vertebral artery transposition for revascularization of the posterior circulation: a critical assessment of temporary and permanent complications and outcomes

OBJECT

Despite advances in medical management and endovascular therapies, including the introduction of statins, antiplatelet agents, and drug-eluting stents, some patients experience medically refractory vertebrobasilar insufficiency and may benefit from robust surgical revascularization. The aim of this study was to evaluate such patients after surgical revascularization, emphasizing long-term outcomes and rates of complications.

METHODS

The authors retrospectively identified 22 patients (5 women and 17 men) whose mean age was 69.1 years (range 48-81 years) who underwent revascularization of the posterior circulation via a proximal vertebral artery-carotid artery transposition between 2005 and 2013. The patients' conditions before surgery were clinically summarized, and long-term outcomes and complication rates after surgery were evaluated.

RESULTS

All the patients were symptomatic before surgery although they received the best medical therapy as defined by their primary care physician. Presenting symptoms consisted of stroke, transient ischemic attacks (TIAs), and/or findings attributable to posterior circulation hypoperfusion. There were no deaths associated with revascularization surgery. The postoperative complication rate was 45.5%, which included 3 cases of recurrent laryngeal nerve palsy, 1 case of thoracic duct injury, 2 cases of TIA, and 4 cases of Horner's syndrome. The thoracic duct injury was identified intraoperatively and ligated without sequelae, all the TIAs resolved within 24 hours of surgery, all 4 sympathetic plexus injuries resolved, and all but 1 of the recurrent laryngeal nerve palsies resolved, resulting in a 4.5% complication rate in a mean follow-up period of 8.8 months. All the patients had resolution of their presenting symptoms, and a single patient had symptomatic restenosis that required stenting and angioplasty, resulting in a restenosis rate of 4.5%.

CONCLUSIONS

Despite the optimization of medical therapies and lifestyle modifications, a select subset of patients with posterior vascular circulation insufficiency remains. In the authors' experience, vertebral artery-carotid artery transposition provides a surgical option with relatively low long-term complication and restenosis rates that are comparable or lower than those reported with endovascular treatment.

Balloons in endovascular neurosurgery: history and current applications

The use of balloons in the field of neurosurgery is currently an essential part of our clinical practice. The field has evolved over the last 40 years since Serbinenko used balloons to test the feasibility of occluding cervical vessels for intracranial pathologies. Since that time, indications have expanded to include sacrificing cervical and intracranial vessels with detachable balloons, supporting the coil mass in wide-necked aneurysms (balloon remodeling technique), and performing intracranial and cervical angioplasty for atherosclerotic disease, as well as an adjunct to treat arteriovenous malformations. With the rapid expansion of endovascular technologies, it appears that the indications and uses for balloons will continue to expand. In this article, we review the history of balloons, the initial applications, the types of balloons available, and the current applications available for endovascular neurosurgeons.

Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated guideline is to provide comprehensive and timely evidence-based recommendations on the prevention of future stroke among survivors of ischemic stroke or transient ischemic attack. The guideline is addressed to all clinicians who manage secondary prevention for these patients. Evidence-based recommendations are provided for control of risk factors, intervention for vascular obstruction, antithrombotic therapy for cardioembolism, and antiplatelet therapy for noncardioembolic stroke. Recommendations are also provided for the prevention of recurrent stroke in a variety of specific circumstances, including aortic arch atherosclerosis, arterial dissection, patent foramen ovale, hyperhomocysteinemia, hypercoagulable states, antiphospholipid antibody syndrome, sickle cell disease, cerebral venous sinus thrombosis, and pregnancy. Special sections address use of antithrombotic and anticoagulation therapy after an intracranial hemorrhage and implementation of guidelines.

Advances and Innovations in Revascularization of Extracranial Vertebral Artery

Revascularization of the extracranial vertebral artery has evolved significantly since the adoption of endovascular techniques. The current neurosurgical armamentarium includes microsurgical and endovascular approaches. The indications for each treatment modality, however, still need to be further delineated. In contrast to carotid artery endarterectomy and carotid artery angioplasty/stenting, there is limited comparative evidence on the efficacy of medical, open, and endovascular treatment of atherosclerotic disease of the extracranial vertebral artery. More recently, drug-eluting stents have gained momentum after high rates of in-stent restenosis have been reported with bare metal stents placed in the vertebral artery. In this article, we discuss the indications, clinical assessment, and surgical nuances of microsurgical and endovascular revascularization for atherosclerotic disease of the extracranial vertebral artery. Despite a general tendency to consider endovascular treatment in the majority of patients, ultimately, open and endovascular revascularization of extracranial vertebral artery should be regarded as complementary therapies and both treatment options need to be discussed in selected patients.

Stent placement for atherosclerotic stenosis of the vertebral artery ostium: angiographic and clinical outcomes in 117 consecutive patients

BACKGROUND

Although it is thought to be a safe treatment option, the main concerns related to treating vertebral artery ostium (VAO) stenosis with stents have been the rate of restenosis and the uncertain long-term results.

OBJECTIVE

To evaluate the angiographic and clinical results of stent placement for atherosclerotic stenosis of the VAO.

METHODS

One hundred seventeen consecutive patients with atherosclerotic VAO stenosis were treated with stent placement over a period of 12 years. All patients were retrospectively analyzed through the use of a prospectively collected database. The indication criteria for this treatment protocol were symptomatic severe VAO stenoses (> 60%) and asymptomatic severe VAO stenoses (> 60%) with incidentally detected infarction in the posterior circulation. The target diameter of stent dilatation from 1997 to 2000 was the normal vessel diameter just distal to the lesion. Moderate overdilation in the proximal portion of the stents has been performed since 2001.

RESULTS

Successful dilatation was obtained in 116 of 117 cases. Transient neurological complications developed in 2 patients; however, no patients experienced any permanent neurological complications. One hundred four patients underwent follow-up angiography at 6 months after stenting. The restenosis rate at the 6-month follow-up was 9.6% (10 of 104). Until 2000, the restenosis rate after stenting was 13.3%. Since 2001, the restenosis rate has decreased to 4.5%. The median clinical follow-up period was 48 months. The annual rate of strokes in the posterior circulation was 0.95%.

CONCLUSION

Stent placement for atherosclerotic VAO stenosis is considered to be a feasible and safe treatment and may be effective for stroke prevention. The moderate overdilation of stents may be an effective modality for the prevention of restenosis.