Showing papers on "Cerebral Revascularization published in 2009"

Predictors of Good Clinical Outcomes, Mortality, and Successful Revascularization in Patients With Acute Ischemic Stroke Undergoing Thrombectomy Pooled Analysis of the Mechanical Embolus Removal in Cerebral Ischemia (MERCI) and Multi MERCI Trials

Abstract: Background and Purpose— The Mechanical Embolus Removal in Cerebral Ischemia (MERCI) and Multi MERCI trials evaluated the safety and efficacy of thrombectomy in the treatment of intracranial arterial occlusions within 8 hours of symptom onset. We sought to determine the predictors of clinical and angiographic outcomes in these patients. Methods— The trial cohorts were combined in a data set of 305 patients. Twenty-eight baseline variables were included in univariate and multivariate analyses to define the independent predictors of good outcomes (modified Rankin Scale score ≤2), mortality, and successful revascularization (Thrombolysis In Myocardial Ischemia 2 to 3 flow). Results— In the univariate analysis, final revascularization, baseline National Institutes of Health Stroke Scale, age, and systolic blood pressure were associated with both good outcomes and mortality at 90 days (P<0.0018 for all). In the multivariate analysis, final revascularization (OR, 20.4; 95% CI, 7.7 to 53.9; P<0.0001), baseline Na...

MR and CT Monitoring of Recanalization, Reperfusion, and Penumbra Salvage Everything That Recanalizes Does Not Necessarily Reperfuse!

Abstract: Revascularization therapies for acute stroke patients aim to rescue the ischemic penumbra by restoring the patency of the occluded artery ("recanalization") and the downstream capillary blood flow ("reperfusion"). This article reviews the definition of recanalization and reperfusion used in stroke clinical trials and their limitations and proposes a study design to determine the relative importance of recanalization, reperfusion, and collateral flow in evaluating the efficacy of revascularization therapies for acute ischemic stroke.

Understanding and treating moyamoya disease in children.

Abstract: Moyamoya disease, a known cause of pediatric stroke, is an unremitting cerebrovascular occlusive disorder of unknown etiology that can lead to devastating, permanent neurological disability if left untreated. It is characterized by progressive stenosis of the intracranial internal carotid arteries and their distal branches and the nearly simultaneous appearance of basal arterial collateral vessels that vascularize hypoperfused brain distal to the occluded vessels. Moyamoya disease may be idiopathic or may occur in association with other syndromes. Most children with moyamoya disease present with recurrent transient ischemic attacks or strokes. Although there is no definitive medical treatment, numerous direct and indirect revascularization procedures have been used to improve the compromised cerebral circulation, with outcomes varying according to procedure type. Such techniques improve the long-term outcome of patients with both idiopathic and syndrome-associated moyamoya disease. This review provides a comprehensive discussion of moyamoya disease in children, with an emphasis on the most effective surgical treatment options.

Age-dependent revascularization patterns in the treatment of moyamoya disease in a European patient population.

Abstract: Object Different revascularization procedures are used in the treatment of patients with moyamoya disease (MMD). The aim of this study was to investigate the relative contribution of direct and indirect revascularization procedures to the restoration of collateral blood supply in adult and pediatric patients with MMD. Methods The authors performed 39 combined cerebral revascularization procedures (standard extraintracranial bypass [STA-MCA bypass] plus encephalomyosynangiosis [EMS]) in 10 pediatric and 10 adult patients. All patients underwent physical examination and digital subtraction angiography before and 6 months after surgery. The STA-MCA bypass and EMS function were graded as Grade I (poor), II (moderate), or III (good) on the basis of the angiograms. Results In pediatric patients, bypass function was Grade I in 12, Grade II in 8, and Grade III in 0 hemispheres; EMS function was Grade I in 0, Grade II in 12, and Grade III in 8 hemispheres. In the adult patients, bypass function was Grade I in 8, G...

Clinical significance of posterior circulation changes after revascularization in patients with moyamoya disease.

Abstract: Objective: It has been noted that the posterior circulation serves as an important source of collateral blood supply in moyamoya disease. Since most of the literature has focused on

Management of giant middle cerebral artery aneurysms with incorporated branches: partial endovascular coiling or combined extracranial-intracranial bypass--a team approach.

Abstract: Objective Our goal was to assess the long-term anatomic and clinical outcomes in patients with giant middle cerebral artery (MCA) aneurysms treated by endovascular coil embolization alone or in combination with cerebral revascularization. Methods One hundred twenty-six patients with giant intracranial aneurysms were endovascularly treated at the University of California, Los Angeles, between 1990 and 2007. Of these, 9 patients had partially thrombosed MCA aneurysms with incorporated branches. Five patients presented with symptoms of mass effect, 3 had seizures, 2 had episodes of brain ischemia, and 1 presented with acute subarachnoid hemorrhage. Results Three wide-neck saccular aneurysms were almost completely coil occluded, leaving only small neck remnants that were intended to preserve the patency of incorporated MCA branches. The other 6 fusiform aneurysms were effectively treated by superficial temporal artery-MCA or occipital artery-MCA bypass, followed by complete coil occlusion of these aneurysms. Immediate angiograms and mid- or long-term neuroradiological imaging follow-up examinations revealed complete obliteration or near-complete occlusion (90%-99%) of the aneurysms in all 9 patients. Seven patients had a favorable long-term clinical outcome, and 1 patient died as a result of unrelated congestive heart failure. One patient required emergent surgical aneurysm thrombectomy because of inadvertent coil occlusion of the frontal opercular artery, which was not protected by the bypass, and the patient subsequently sustained a moderate neurological disability. Conclusion Giant MCA aneurysms with branch incorporations and other unfavorable features such as intraluminal thrombus, mural calcification, and fusiform configuration can be effectively treated with a team approach, using coil embolization after protective surgical bypass. When aneurysms with MCA branches incorporated into the neck rather than the dome are treated by endovascular techniques alone, long-term angiographic follow-up is necessary to assess and further treat any significant remnant.

Peripheral intracranial aneurysms: management challenges in 60 consecutive cases.

Abstract: Object The authors report the management and outcomes of 55 patients with 60 intracranial aneurysms arising distal to the major branch points of the circle of Willis and vertebrobasilar system. Methods Between July 1997 and December 2006, the authors' neurovascular service treated 2021 intracranial aneurysms in 1850 patients. The database was reviewed retrospectively to identify peripherally located intracranial aneurysms. Aneurysms that were mycotic and aneurysms that were associated with either an arteriovenous malformation or an atrial myxoma were excluded from review. Results The authors encountered 60 peripheral intracranial aneurysms in 55 patients. There were 42 small, 7 large, and 11 giant lesions. Forty-one (68%) were unruptured, and 19 (32%) had bled. Fifty-three aneurysms were treated surgically by using direct clip reconstruction in 26, trapping or proximal occlusion with distal revascularization in 21, excision with end-to-end anastomosis in 3, and circumferential wrap/clip reconstruction in ...

Hyperperfusion syndrome following endovascular cerebral revascularization

Abstract: Endovascular cerebral revascularization is becoming a frequently used alternative to surgery for the treatment of atherosclerotic disease, especially in the intracranial circulation where options are limited. Recent literature regarding the equivalent efficacy of carotid artery stenting and carotid endarterectomy in certain patient populations, as well as the recognition of the significant risk for recurrent stroke posed by intracranial lesions, will only serve to amplify this trend. Hyperperfusion syndrome has been well documented in the setting of carotid endarterectomy; however, a paucity of literature exists regarding the incidence, pathophysiology, and management as it relates to percutaneous interventions. The purpose of this review is to outline the current state of knowledge, with particular attention to the distinct attributes of endovascular treatment that would be expected to modify the course of hyperperfusion syndrome.

Graft selection in cerebral revascularization.

Abstract: Cerebral revascularization constitutes an important treatment modality in the management of complex aneurysms, carotid occlusion, tumor, and moyamoya disease. Graft selection is a critical step in the planning of revascularization surgery, and depends on an understanding of graft and regional hemodynamics, accessibility, and patency rates. The goal of this review is to highlight some of these properties.

Revival of extra-intracranial bypass surgery.

Abstract: Purpose of review Extra-intracranial bypass surgery has regained significant relevance over the past years. The aim of this review is to highlight the current indications and recent developments in this field. Recent findings One main indication today is stroke prevention by flow augmentation in the setting of chronic cerebral hemodynamic ischemia which is defined as a combination of steno-oclusive cerebrovascular disease, inadequate collateralization, and loss of cerebrovascular reserve capacity. Another indication is flow replacement in the context of therapy of complex aneurysms and skull base tumors. The herein proposed revival of bypass surgery is due to the progress in individualized, tailored therapeutic strategies as well as patient selection. Furthermore, we witness a dramatic improvement in the surgical technique as well as the development of a broad armamentarium of different bypass types, which today allow tailored revascularization strategies for our patients. Finally, the revival of bypass surgery is also explained by significant technical progress. One of the major developments within the last years is the Excimer laser-assisted nonocclusive anastomosis technique which allows performance of an anastomosis without the need for temporary clipping, thus dramatically reducing the risk for perioperative ischemia in bypass surgery. Summary Extra-intracranial bypass surgery has become a central part of a highly specialized, interdisciplinary strategy for the therapy of complex aneurysms and skull base tumors.

The evolution of cerebral revascularization surgery

Abstract: Among the relatively few surgeons to be awarded the Nobel Prize was Alexis Carrel, a French surgeon and pioneer in revascularization surgery at the turn of the 20th century. The authors trace the humble beginnings of cerebral revascularization surgery through to the major developments that helped shape the modern practice of cerebral bypass surgery. They discuss the cornerstone studies in the development of this technique, including the Extracranial/Intracranial Bypass Study initiated in 1977. Recent innovations, including modern techniques to monitor cerebral blood flow, microanastomosis techniques, and ongoing trials that play an important role in the evolution of this field are also evaluated.

Operative nuances of an occipital artery to posterior inferior cerebellar artery bypass

Abstract: Occipital artery to posterior inferior cerebellar artery bypasses remain an important tool for cerebrovascular neurosurgeons, particularly in the management of complex aneurysms of the posterior inferior cerebellar artery requiring proximal occlusion or trapping. The procedure requires meticulous technique and attention to detail. The authors outline their technique for accomplishing this bypass emphasizing nuances for complication avoidance.

Microsurgical revascularization of proximal vertebral artery: a single-center, single-operator analysis.

Abstract: OBJECTIVE: High rates of restenosis after stenting to treat vertebral artery (VA) origin disease have revitalized interest in microsurgical revascularization for this condition This study analyzes the outcomes of microsurgical revascularization used to treat proximal VA occlusive disease METHODS: Between 1986 and 2007, 29 patients (19 men, 10 women; age range, 35-93 years) underwent microsurgical revascularization for proximal VA disease Their medical records were reviewed retrospectively for presenting symptoms, presence of comorbidities, target lesion characteristics, contralateral VA findings, procedure-related morbidity, and clinical and radiographic outcomes RESULTS: Thirteen, 7, and 6 patients underwent VA-to-carotid artery transposition, endarterectomy, or both, respectively Two patients underwent subclavian endarterectomy plus vertebral endarterectomy, and 1 patient underwent carotid endarterectomy associated with VA transposition There were no cases of periprocedural stroke or death Permanent procedure-related neurological complications included 1 case of Horner's syndrome and 1 case of hoarseness Two of the 27 patients available for follow-up had new neurological symptoms attributable to the vertebrobasilar system Follow-up imaging was available for 14 patients, only 1 of whom developed restenosis, most likely related to disease progression at the site of anastomosis CONCLUSION: Microsurgical revascularization is a good alternative treatment for proximal VA occlusive disease Randomized studies are needed to compare the efficacy of surgical revascularization and stenting, especially drug-eluting stents, for this indication

Minimally occlusive laser vascular anastomosis (MOLVA): experimental study

Abstract: Temporary occlusion of an intracranial artery during microvascular anastomosis is a major risk factor in cerebrovascular surgery. A new laser vascular welding technique that minimizes the occlusion time of the recipient vessel has been developed and is described in this report. A new minimally occlusive technique of end-to-side microvascular anastomosis was developed employing a diode laser in association with the application of a chromophore in our experimental model of double end-to-side anastomosis. The implantation of a vein graft on the patent carotid artery was obtained through the application of three interrupted sutures at each anastomotic site; the carotid was then clamped, two arteriotomies were performed, followed by the application of a fourth suture and of the laser welding procedure on each anastomosis. Monitoring of the temperature at the site of the anastomosis was introduced in order to control the welding technique. The time of the clamping of the carotid artery was 12 min to perform two end-to-side anastomoses (i.e., 6 min for each anastomosis). All bypasses were patent after a follow-up of 90 days and histological study confirmed good preservation of the vascular wall. Our laser-assisted technique of vascular anastomosis reduces the duration of the clamping of the recipient artery down to 6 min. This technique can minimize the risk of cerebral ischemia associated with occlusion of a recipient artery in intracranial bypass procedures, promoting an improved vascular healing process with a lower risk of thrombosis and occlusion.

Predictors of patency of excimer laser-assisted nonocclusive extracranial-to-intracranial bypasses

Abstract: Object Excimer laser–assisted nonocclusive anastomosis (ELANA) is a technique that can be used for extracranial-to-intracranial (EC-IC) bypasses, without the necessity of temporary occlusion of the donor or recipient artery Information on predictors of patency of EC-IC bypasses in general and the ELANA bypass in particular is sparse The authors studied 159 ELANA EC-IC bypasses to find predictors of patency Methods From a prospective database of patients who underwent EC-IC bypass surgery, 143 consecutive patients who underwent a total of 159 ELANA bypasses were studied The associations of patient characteristics, surgical aspects, and technical aspects specific to the ELANA technique with intraoperative and postoperative bypass patency were studied using logistic regression analysis Results At the end of the operation, 146 (92%) of the 159 bypasses were patent A first attempt to create a bypass was almost 8 times more likely (OR 76, 95% CI 21–275; p = 002) to result in a patent bypass than a sec

C-Port Flex-A-assisted automated anastomosis for high-flow extracranial-intracranial bypass surgery in patients with symptomatic carotid artery occlusion: a feasibility study. Clinical article.

Abstract: Object Preliminary experience with the C-Port Flex-A Anastomosis System (Cardica, Inc.) to enable rapid automated anastomosis has been reported in coronary artery bypass surgery. The goal of the current study was to define the feasibility and safety of this method for high-flow extracranial-intracranial (EC-IC) bypass surgery in a clinical series. Methods In a prospective study design, patients with symptomatic carotid artery (CA) occlusion were selected for C-Port–assisted high-flow EC-IC bypass surgery if they met the following criteria: 1) transient or moderate permanent symptoms of focal ischemia; 2) CA occlusion; 3) hemodynamic instability; and 4) had provided informed consent. Bypasses were done using a radial artery graft that was proximally anastomosed to the superficial temporal artery trunk, the cervical external, or common CA. All distal cerebral anastomoses were performed on M2 branches using the C-Port Flex-A system. Results Within 6 months, 10 patients were enrolled in the study. The distal ...

Intracranial angioplasty and stent placement for direct cerebral revascularization of nonacute intracranial occlusions and near occlusions.

Abstract: Object The authors reviewed their experience in 7 cases of nonacute intracranial occlusions and near occlusions in which the patients underwent intracranial angioplasty and stent implantation for direct cerebral revascularization. Methods Between 2005 and 2008, 4 men and 3 women underwent direct cerebral revascularization of nonacute intracerebral occlusions or near occlusions. Five patients had chronic angiographically documented occlusion and 2 patients had chronic angiographically documented near occlusions. The locations of the treated vessels included 2 supraclinoid internal carotid arteries, 4 middle cerebral arteries, and 1 vertebral artery. Prior to intervention, all patients were symptomatic and experienced strokes ipsilateral to their occlusions. In addition, all patients had clinical or radiographic evidence of ongoing hemodynamic compromise. Five patients underwent successful intracranial angioplasty and stent placement and 2 patients underwent successful intracranial balloon angioplasty alone...

Lies, Damned Lies, and Statistics∗: A Neurosurgical Perspective on the International Randomized Trial of Extracranial to Intracranial Arterial Bypass Surgery

Abstract: The abrupt occurrence of a devastating stroke has been referred to as "super death." It has long been realized that ischemic cerebral vascular disease may become symptomatic with a wide variety of clinical patterns. A robust circle of Willis has been recognized for its major protective function in many cases. When it became possible to actually create new collateral circulation to the brain by microsurgical techniques, significant enthusiasm arose. This enthusiasm was interrupted by the negative results of the international randomized trial. Further analysis of the trial raised serious questions regarding incomplete randomization by contributors to the study, and there remains uncertainty about important potential benefits for some individuals. Long-term follow-up of 3 patients having different and complex circumstances is described to emphasize this concern. After the creation of reliable collateral circulation to the brain, none has experienced new ischemic deficit during the subsequent follow-up of 27, 25, and 12 years, respectively.

Bypass and revascularization in the treatment of complex intracranial aneurysms

Abstract: Objective To study the application of bypass and revascularizatiou in the treatment of complex intracranial aneurysms.Method From Nov 2002 to Mar 2008,twenty-four patients with complex intracranial aneurysms underwent aneurysmectomy followed by primary reanastomosis,aneurysm trapping followed by saphenous vein or superficial temporal artery bypass procedures.Results Four aneurysms were excised with primary reanastomosis,16 of 24 aneurysms were trapped followed by saphenous vein high-flow bypass,and 4 were excised followed by superficial temporal artery low-flow bypass.At discharge,twenty-two out of the 24 patients had a Glasgow Outcome Scale score of 4 to 5,one patient was severe disability and one was dead.Conclusions Bypass or revascularization is a sound and reliable procedure in the treatment of complex intracranial aneurysms.The M2 segment of middle cerebral artery is the optimal recipient to accept bypass vessel. Key words: Intracranial aneurysm; Bypass; Cerebral revascularization

Hyperacute stent placement in acute cervical internal carotid artery occlusions: the potential role of magnetic resonance imaging

Abstract: Cervical internal carotid artery (ICA) occlusions causing acute ischemic stroke have extremely poor outcomes without rapid re-establishment of cerebral perfusion Given the high risk for early recurrent stroke, carotid stenting at the time of intra-arterial therapy may be crucial to improving outcomes To our knowledge, there are only two prior case series that address intra-arterial reperfusion therapy and stent placement within six hours of stroke onset (the hyperacute period) We present two cases to further support the feasibility of this intervention in the hyperacute period, and report the potential utility of MRI in identifying patients most likely to benefit from this procedure

Surveillance: Diagnosis and Management of In-Stent Restenosis

Abstract: Carotid endarterectomy (CEA) is the preferred treatment for symptomatic [1–3] and asymptomatic [4, 5] patients with high-grade extracra-nial carotid stenosis, compared with the best medical therapy. The increase in the number of CEAs done worldwide has resulted in a number of post-CEA carotid restenosis (CR) cases. Carotid artery stenting (CAS) has recently emerged as a less-invasive alternative to CEA for cerebral revascularization. Our institution [6–10], along with others [11–14], has demonstrated that CAS is technically feasible and safe in high-risk patients. Two randomized trials [14, 15] and results from the lead-in phase of the Carotid Revascularization, Endarterectomy vs. Stent Trial (CREST) [16] reported low periprocedural complication rates with CAS, indicating clinical equipoise between the two procedures. This resulted in the approval of CAS in the United States in high-risk patients with significant carotid stenosis (≥ 70%) and neurological symptoms (ipsilateral stroke, transient ischemic attack, and amaurosis fugax) [17]. Two additional randomized trials were not able to demonstrate equivalence of CAS with CEA with respect to postprocedural stroke, myocardial infarction, or death. These results notwithstanding, it is clear that the number of CAS procedures will continue to progressively increase until a more definitive answer is available from larger studies powered to assess superiority of one procedure over the other (e.g., the NIH-sponsored CREST).

Carotid Artery Stenting

Abstract: Stroke is the third most common cause of death and the leading cause of disability in the United States. Management of identifiable risk factors and careful selection of patients for revascularization of extracranial carotid artery stenosis constitute the current approach toward reducing the morbidity and mortality associated with stroke. The controversy over proper management of carotid stenosis prompted several randomized controlled multi-institutional trials during the past 2 decades. They have provided statistically reliable results that form the basis of current management recommendations. Carotid endarterectomy (CEA), performed with a low peri-procedural complication rate, is the only form of mechanical cerebral revascularization for which level 1 evidence of clinical effectiveness in preventing stroke has been reported (Barnett et al. 1998; Executive Committee for the Asymptomatic Carotid Atherosclerosis Study 1995).

Age-dependent revascularization patterns in the treatment of moyamoya disease in a European patient population

Abstract: Object. Different revascularization procedures are used in the treatment of patients with moyamoya disease (MMD). The aim of this study was to investigate the relative contribution of direct and indirect revascularization procedures to the restoration of collateral blood supply in adult and pediatric patients with MMD. Methods. The authors performed 39 combined cerebral revascularization procedures (standard extraintracranial bypass [STA-MCA bypass] plus encephalomyosynangiosis [EMS]) in 10 pediatric and 10 adult patients. All patients underwent physical examination and digital subtraction angiography before and 6 months after surgery. The STA-MCA bypass and EMS function were graded as Grade I (poor), II (moderate), or III (good) on the basis of the angiograms. Results. In pediatric patients, bypass function was Grade I in 12, Grade II in 8, and Grade III in 0 hemispheres; EMS function was Grade I in 0, Grade II in 12, and Grade III in 8 hemispheres. In the adult patients, bypass function was Grade I in 8, Grade II in 8, and Grade III in 3 hemispheres; EMS function was Grade I in 10 hemispheres, Grade II in 5, and Grade III in 1 hemisphere. In the pediatric patients disease was classified as improved in 14 hemispheres on the basis of clinical results and stable in 6. In the adults it was classified as improved in 12 hemispheres stable in 7 hemispheres. Conclusions. Combined revascularization led to good angiographic and clinical results in both patient populations. Especially in pediatric patients, EMS represents a suitable alternative to bypass surgery. (DOI: 10.3171.2009.1.FOCUS08298) key W or D s • moyamoya disease • revascularization • Europe