Therapy of Basilar Artery Occlusion

Current recommendations for endovascular interventions in the treatment of ischemic stroke

Ischemic stroke remains one of the leading cause of adult death and disability in the United States. Reperfusion of the occluded vessel is the standard of care in the setting of acute ischemic stroke according to established guidelines. Since the introduction of intravenous (IV) recombinant tissue plasminogen activator (rt-PA) in the late 1990s, significant advances have been made in methods to deliver thrombolytic agents and in devices for mechanical recanalization of occluded vessels. Furthermore, improvements in patient selection contribute to achievement of good clinical outcomes after endovascular therapy. This article summarizes findings from recent clinical trials and presents evidence-based guidelines for endovascular interventions in the treatment of ischemic stroke.

Intraarterial thrombolysis and stent placement for acute basilar artery occlusion

PURPOSE

To study retrospectively the prognostic factors for acute basilar artery occlusion treated with intraarterial thrombolysis and stent placement.

MATERIALS AND METHODS

Within 3-48 hours of disease onset, 52 patients with basilar artery occlusion were treated with emergency intraarterial thrombolysis with recombinant tissue plasminogen activator (rtPA) or urokinase (UK) or intraarterial thrombolysis combined with stent placement. Sixteen patients simultaneously received stent placement for the partial recanalization of basilar artery occlusion after intraarterial thrombolysis. The National Institutes of Health Stroke Scale (NIHSS) scores and the modified Rankin Scale (mRS) scores of the patients were estimated.

RESULTS

A favorable clinical outcome occurred in 22 patients (42.3%), and 20 patients (38.5%) died. The survival rate was 61.5% (32 patients). Successful recanalization of basilar artery occlusion was achieved in 24 patients (46.2%), and partial recanalization was achieved in 16 patients (30.7%). The rate of recanalization was 76.9%. NIHSS scores less than 14, treatment time window less than 24 hours, and a good recanalization were markedly correlated with good clinical prognosis. NIHSS scores less than 14 and treatment time window less than 24 hours were significantly correlated with recanalization. NIHSS scores less than 14 and good recanalization could act as independent predictors for clinical prognosis.

CONCLUSIONS

NIHSS scores less than 14 on admission and successful recanalization can predict favorable outcome for patients with basilar artery occlusion. This study shows that intraarterial thrombolysis and stent placement may be a useful treatment for acute basilar artery occlusion.

Basilar artery thrombosis: imaging and endovascular therapy

PURPOSE

Basilar artery thrombosis represents a rare type of ischaemic stroke with a mortality rate of 80%-90% if not promptly treated. The aim of our study was to review our experience with computed tomography angiography (CTA) in the diagnosis of basilar artery thrombosis and its treatment with endovascular procedures.

MATERIALS AND METHODS

Our retrospective study is based upon 59 nontrauma patients with episodes of sudden loss of consciousness. Patients were investigated using unenhanced brain CT followed by intracranial CTA (16-slice CT) when no parenchymal haemorrhage was detected. Patients with a CTA diagnosis of basilar artery thrombosis were considered for endovascular treatment. CTA accuracy was evaluated by considering the 12 patients who underwent endovascular angiography (the gold standard). The success of endovascular therapy was evaluated by considering the degree of microcirculatory reperfusion.

RESULTS

After the exclusion of 33 patients affected by parenchymal or subarachnoid haemorrhage, the final study consisted of 26 patients who underwent CTA. Basilar artery thrombosis was diagnosed in 15 of them, and 12 were treated at our institution. The comparison between CTA and endovascular angiography showed 100% agreement in evaluating occlusion site and extension. Seven patients underwent intra-arterial lysis, and five underwent mechanical clot removal.

CONCLUSIONS

CTA, with its wide availability and rapid execution times, is the most indicated examination in the case of suspected basilar artery thrombosis. Although there is a lack of randomised controlled prospective studies suggesting the most appropriate therapeutic approach to basilar artery thrombosis, our study lends weight to the role of interventional neuroradiology in the treatment of this condition.

Hyperdense basilar artery sign diagnoses acute posterior circulation stroke and predicts short-term outcome

INTRODUCTION

It is well established that the hyperdense middle cerebral artery sign is a specific marker for early ischemia in anterior circulation. However, little is known about the hyperdense basilar artery sign (HDBA) in posterior circulation. Our aim was to determine whether the HDBA sign has utility in early diagnosis of acute posterior circulation stroke and prediction of short-term outcome.

METHODS

Three-blinded readers examined unenhanced computed tomography scans for the HDBA sign, and materials were classified into two groups according to this sign. Vascular risk factors, admission and discharge National Institute of Health Stroke Scale (NIHSS) scores, short-term outcome, and radiological findings between the two groups were compared.

RESULTS

One hundred and twenty-six cases of acute posterior circulation stroke (PCS) were included in the study. No statistically significant differences were found in risk factors of ischemic stroke, except atrial fibrillation (P=0.025). Admission and discharge NIHSS scores for the positive HDBA group were significantly higher than scores for the negative HDBA group (P=0.001, 0.002, respectively). The infarction territory for the positive HDBA group was mainly multi-region in nature (51.6%, P<0.001), while the negative HDBA group showed mainly middle territory infarction. Significant independent predictors of short-term outcome included the HDBA sign (P<0.001) and admission NIHSS scores (P<0.001).

CONCLUSION

Approximately half of the HDBA patients showed multi-region infarction and a serious neurological symptom. Based on our results, this sign might not only be helpful in early diagnosis of acute PCS but also be able to correlate with a poor short-term outcome.

Endovascular Recanalization of the Subacute to Chronically Occluded Basilar Artery

INTRODUCTION

Occlusion of the basilar artery (BA) has a poor prognosis. We evaluated technical considerations and complications associated with reopening subacute to chronically occluded BAs.

METHODS

Duration of BA occlusion before revascularization, symptoms and medical management before treatment, and postprocedural antiplatelet regimen and anticoagulation protocols of 9 patients were analyzed. All patients underwent endovascular low-volume balloon angioplasty followed by Wingspan stenting.

RESULTS

The median time between onset of symptoms and treatment was 5 days (range, 2 days to 3.5 years). The median time between documentation of BA occlusion by cerebral angiography or computed tomography angiography and treatment was 3 days (range, 1 day to 8 months). Recanalization was successful in 8 of the 9 patients. Immediately after the procedure, 4 patients were stable, 3 patients improved, and 2 patients were worse. Four patients had periprocedural complications. Four of the 9 patients died, 2 from periprocedural complications. The mean clinical duration of follow-up was 11 months. At latest follow-up, the modified Rankin Scale scores for the 5 surviving patients were 0, 0, 2, 2, and 3, respectively. During the follow-up period, 4 patients improved, 1 patient remained stable, and 1 patient died. The mean angiographic follow-up was 8.6 months. Two patients developed significant in-stent stenosis during this period.

CONCLUSION

With current endovascular techniques, recanalization of chronically occluded BAs is feasible. The procedure carries substantial risks and should be reserved for patients with medically refractory symptoms. Careful postprocedural medical management and radiographic follow-up are warranted to prevent in-stent restenosis.

Endovascular recanalization of acute intracranial vertebrobasilar artery occlusion using local fibrinolysis and additional balloon angioplasty

INTRODUCTION

Vertebrobasilar artery occlusion (VBO) produces high mortality and morbidity due to low recanalization rate utilization in endovascular therapy. The use of percutaneous transluminal angioplasty (PTA) to improve recanalization rate additional to local intra-arterial fibrinolysis (LIF) was investigated in this study. Results obtained following recanalization therapy in acute intracranial VBO are reported.

METHODS

Eighteen consecutive patients with acute VBO underwent LIF with or without PTA, from August 2000 to May 2006. Eight patients were treated using LIF alone, and ten required additional PTA. Rate of recanalization, neurological status before treatment, and clinical outcomes were evaluated.

RESULTS

Of 18 patients, 17 achieved recanalization. One procedure-related complication of subarachnoid hemorrhage occurred. Overall survival rate was 94.4% at discharge. Seven patients achieved good outcomes [modified Rankin scale (mRS) 0-2], and the other 11 had poor outcomes (mRS 3-6). Five of six patients who scored 9-14 on the Glasgow Coma Scale (GCS) before treatment displayed good outcomes, whereas ten of 12 patients who scored 3-8 on the GCS showed poor outcomes. GCS prior to treatment showed a statistically significant correlation to outcomes (p < 0.05). Moreover, the National Institutes of Health Stroke Scale (NIHSS) before treatment correlated well with mRS (correlation coefficient 0.487). No statistical difference between the good and poor outcome groups was observed for the duration of symptoms, age, etiology, and occlusion site.

CONCLUSIONS

Endovascular recanalization can reduce mortality and morbidity of acute VBO. Good GCS and NIHSS scores prior to treatment can predict the efficacy of endovascular recanalization.

Fatal basilar thrombosis possibly related to minor cervical trauma: a case report

Background. Basilar thrombosis is a potentially fatal event, whose traumatic etiology has been repeatedly stated. Methods. We performed the autopsy and the microscopic examination of the brain stem structures from an individual, whose sudden death raised logical suspicions regarding the causative factor. Results. The brain was swollen and clearly hyperemic; a massive basilar thrombus with complete occlusion of the median segment of the basilar artery was macroscopically seen. The brainstem showed an infarcted zone in the pons, with secondary hemorrhagic changes, mainly in the form of multiple petechial hemorrhages. Pontine arteries showed extensive alterations, mainly in the form of severed endothelium, which suggested a thrombotic-traumatic mechanism as the main etiological factor. Conclusions. Minor injuries, such as slight whiplashes, abrupt neck movements, neck trauma related to the slowing down of the vehicles, and critical neck positioning, can all of them explain a thrombotic event in the basilar artery, leading to a fatal occurrence. Other risk factors may obviously concur, but their importance seems unclear.

Spontaneous recanalization of the basilar artery with conservative management months after symptom onset

Basilar artery occlusion may be associated with a poor prognosis in the absence of recanalization. Choices in aggressive treatment for this potentially fatal condition vary from intra-arterial or intravenous thrombolysis, endovascular removal, or a combination of the two, with adjunct anti-coagulation therapy. These therapies have proven to be effective in recanalization, whereas conservative management with anti-coagulants alone has had more limited success in the literature. We report a case of basilar artery occlusion managed conservatively with unfractionated heparin, resulting in complete recanalization 3.5 months after symptom onset. Conservative management of basilar artery occlusion with unfractionated heparin was associated with complete recanalization long after symptom onset.

[Therapy of acute ischemic stroke]

New diagnostic and therapeutic developments have led to an innovative approach to stroke therapy. The slogan "time is brain" emphasizes that stroke is a medical emergency comparable to myocardial infarction. The stroke unit conception is an evidence based therapy for all stroke patients and improves outcome significantly. The monitoring of vital signs and the management of stroke specific complications are highly effective. Early secondary prophylaxis reduces the risk of recurrence. The effect of CT based thrombolysis within the time window of 4,5 h has been substantiated by current data. Stroke MRI holds the promise for an improved therapy by patient stratification and by opening the time window. Interventional recanalisation, vascular interventions and hemicraniectomy complement the therapeutic options in the acute phase of stroke.

Thrombolysis for acute ischaemic stroke

BACKGROUND

The majority of strokes are due to blockage of an artery in the brain by a blood clot. Prompt treatment with thrombolytic drugs can restore blood flow before major brain damage has occurred and could improve recovery after stroke. Thrombolytic drugs, however, can also cause serious bleeding in the brain, which can be fatal. One drug, recombinant tissue plasminogen activator (rt-PA), is licensed for use in highly selected patients within three hours of stroke.

OBJECTIVES

To assess the safety and efficacy of thrombolytic agents in patients with acute ischaemic stroke.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched October 2008), MEDLINE (1966 to October 2008) and EMBASE (1980 to October 2008). We contacted researchers and pharmaceutical companies, attended relevant conferences and handsearched pertinent journals.

SELECTION CRITERIA

Randomised trials of any thrombolytic agent compared with control in patients with definite ischaemic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors applied the inclusion criteria and extracted data. We assessed trial quality. We verified the extracted data with the principal investigators of all major trials. We obtained both published and unpublished data if available.

MAIN RESULTS

We included 26 trials involving 7152 patients. Not all trials contributed data to each outcome. The trials tested urokinase, streptokinase, recombinant tissue plasminogen activator, recombinant pro-urokinase or desmoteplase. Four trials used intra-arterial administration, the rest used the intravenous route. Most data come from trials that started treatment up to six hours after stroke; three trials started treatment up to nine hours and one small trial up to 24 hours after stroke. About 55% of the data (patients and trials) come from trials testing intravenous tissue plasminogen activator. Very few of the patients (0.5%) were aged over 80 years. Many trials had some imbalances in key prognostic variables. Several trials did not have complete blinding of outcome assessment. Thrombolytic therapy, mostly administered up to six hours after ischaemic stroke, significantly reduced the proportion of patients who were dead or dependent (modified Rankin 3 to 6) at three to six months after stroke (odds ratio (OR) 0.81, 95% confidence interval (CI) 0.73 to 0.90). Thrombolytic therapy increased the risk of symptomatic intracranial haemorrhage (OR 3.49, 95% CI 2.81 to 4.33) and death by three to six months after stroke (OR 1.31, 95% CI 1.14 to 1.50). Treatment within three hours of stroke appeared more effective in reducing death or dependency (OR 0.71, 95% CI 0.52 to 0.96) with no statistically significant adverse effect on death (OR 1.13, 95% CI 0.86 to 1.48). There was heterogeneity between the trials in part attributable to concomitant antithrombotic drug use (P = 0.02), stroke severity and time to treatment. Antithrombotic drugs given soon after thrombolysis may increase the risk of death.

AUTHORS' CONCLUSIONS

Overall, thrombolytic therapy appears to result in a significant net reduction in the proportion of patients dead or dependent in activities of daily living. This overall benefit was apparent despite an increase both in deaths (evident at seven to 10 days and at final follow up) and in symptomatic intracranial haemorrhages. Further trials are needed to identify which patients are most likely to benefit from treatment and the environment in which thrombolysis may best be given in routine practice.

MULTIMODAL REPERFUSION THERAPY IN PATIENTS WITH ACUTE BASILAR ARTERY OCCLUSION

OBJECTIVE

Multimodal reperfusion therapy (MMRT) has been advocated for the treatment of acute basilar artery occlusion (ABAO). We aimed to identify prognostic factors in patients with ABAO who underwent MMRT.

METHODS

Clinical and radiological data from consecutive ABAO patients were analyzed. All patients underwent MMRT on an emergency basis. Stroke subtypes were categorized according to TOAST (Trial of ORG 10172 in Acute Stroke Treatment) criteria. Good outcome was defined as a modified Rankin Scale score of 3 or less and poor outcome as a score of 4 or more at 30 days poststroke.

RESULTS

Twenty-four patients were included (18 men, 6 women) with a mean age of 54.7 years (age range, 26–70 years). Six patients died (25%), and 8 of the surviving 18 patients (44%) achieved a modified Rankin Scale score of 3 or less at 30 days. We could not identify any clinical or radiological variables that were associated with a greater likelihood of good or poor outcome at 30 days other than the presence of good collateral circulation, which was associated with better outcome on univariate analysis.

CONCLUSION

MMRT resulted in high survival and good outcome rates. We could not identify prognostic factors in patients with ABAO treated with MMRT other than the presence of collateral flow. Our results imply that patients should not be excluded from treatment based on clinical or radiological parameters, and that all patients with ABAO should be given the chance to benefit from therapy.

CT angiography source images predict final infarct extent in patients with basilar artery occlusion

BACKGROUND AND PURPOSE

The posterior circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS) is a 10-point grading system to quantify ischemic changes in the posterior circulation. We analyzed whether pc-ASPECTS on CT angiography (CTA) source images (CTASI) predicted the final infarct extent and hemorrhagic transformation (HT) rate in patients with basilar artery occlusion.

MATERIALS AND METHODS

A pc-ASPECTS score of 10 indicates absence of visible ischemic changes in the posterior circulation, and pc-ASPECTS score of 0 indicates ischemic changes in the midbrain, pons, and bilateral thalami, posterior circulation territories, and cerebellar hemispheres. We retrospectively studied patients with basilar artery occlusion on CTA within 24 hours from symptom onset. We applied pc-ASPECTS to noncontrast CT (NCCT), CTASI, and follow-up images by 3-reader-consensus and assessed HT on follow-up images. We calculated Spearman correlation coefficients and performed linear regression analysis. Final infarct extent and HT rates were compared across dichotomized CTASI pc-ASPECTS groups (>/= 8 vs < 8).

RESULTS

Among 43 patients, median (range) onset to CTA time was 5.0 hours (range, 0.7-24 hours). Pc-ASPECTS on CTASI (r = 0.75; P < .001) but not NCCT (r = 0.29; P = .063) correlated with pc-ASPECTS on follow-up scans. Linear regression demonstrated a significant positive relationship between pc-ASPECTS on CTASI and follow-up scans (R(2) = 0.58; P < 01). Median follow-up pc-ASPECTS was lower in patients with a CTASI pc-ASPECTS < 8 compared with patients with a CTASI pc-ASPECTS of 8 or more, respectively (P < .001). HT rates were 27.3% vs 9.5%, respectively (P = .24). None of 8 patients without thrombolysis had HT on follow-up scans.

CONCLUSIONS

The extent of hypoattenuation on CTASI predicts the final infarct extent in patients with basilar artery occlusion.

Thrombectomy for acute basilar artery occlusion by using double Merci retriever devices and bilateral temporary vertebral artery flow reversal

Basilar artery occlusion is a dramatic clinical event with a high mortality rate if patients are treated by standard medical therapy, including anticoagulation agents. The use of intravenous tissue plasminogen activator or intraarterial thrombolysis recanalizes 30–53 and 64%, respectively, of patients with basilar stroke. Mechanical endovascular treatments allow tailored procedures with quicker results and higher recanalization rates. The authors describe a successful mechanical removal of an obstruction in an acute occlusion of the basilar artery tip involving both proximal segments of posterior cerebral arteries in a 20-year-old man. They used 2 Merci retriever devices at the same time, and performed bilateral proximal vertebral artery occlusion for temporary flow reversal and aspiration.

Endovascular approaches to acute stroke, part 2: a comprehensive review of studies and trials

Reperfusion remains the mainstay of acute ischemic stroke treatment. Endovascular therapy has become a promising alternative for patients who are ineligible for or have failed intravenous (IV) thrombolysis. The conviction that recanalization of properly selected patients is essential for the achievement of good clinical outcomes has led to the rapid and widespread growth in the adoption of endovascular stroke therapies. However, comparisons of the recent reperfusion studies have brought into question the strength of the association between revascularization and improved clinical outcome. Despite higher rates of recanalization, the mechanical thrombectomy studies have demonstrated substantially lower rates of good outcomes compared with IV and/or intra-arterial thrombolytic trials. However, such analyses disregard important differences in clot location and burden, baseline stroke severity, time from stroke onset to treatment, and patient selection in these studies. Many clinical trials are testing novel devices and drugs as well as the paradigm of physiology-based stroke imaging as a treatment-selection tool. The objective of this article is to provide a comprehensive review of the relevant past, current, and upcoming data on endovascular stroke therapy with a special focus on the prospective studies and randomized clinical trials.

[Vertebrobasilar occlusions : Pathophysiology, diagnostics and treatment]

Acute vertebrobasilar occlusions (VBO) are dramatic clinical events with a mortality of up to 90% under standard medical treatment. If VBO is suspected a diagnosis of the vessel status has to be achieved immediately. For this purpose CT/CTA and MRI/MRA are equivalent diagnostic tools in the emergency setting. In contrast to the anterior circulation, local endovascular treatment is the established therapy for the posterior circulation as an underlying arteriosclerotic stenosis remains in 50% of the cases after intravenous fibrinolysis. Nevertheless, systemic fibrinolysis is considered the preferred option in cases where a neurointerventional center cannot be reached within a reasonable time frame and the patient can subsequently be transported for local therapy of a residual stenosis in order to prevent reocclusion ("drip and ship"). Profound clinical and pathophysiological knowledge is the absolute prerequisite for the correct application of state-of-the-art neurointerventional therapy. This review paper focuses on the clinical and pathophysiological details that are crucial for decision-making.

MRI mismatch-based intravenous thrombolysis for isolated cerebellar infarction

BACKGROUND AND PURPOSE

Cerebellar infarctions constitute a significant proportion of ischemic strokes and carry a substantial morbidity and mortality mainly because of swelling in the posterior fossa. No specific acute therapy is established, and patients are usually excluded from intravenous thrombolysis (IVT).

METHODS

Two patients presented in an extended time window of 5 and 7 hours to our emergency department with sudden onset of severe cerebellar symptoms. After emergency MRI demonstrated superior cerebellar artery (SCA) occlusion with hypoperfusion of the respective territory and only minor DWI lesions, IVT was administered. Both patients recovered within a few hours after therapy and follow-up MRI on day 1 after treatment demonstrated only minor infarction.

CONCLUSIONS

We present to our knowledge the first cases of MRI mismatch-based IVT in an extended time window in patients with isolated SCA-infarctions. More studies are needed to evaluate IVT in this patient population. Modern imaging techniques might be helpful to select patients for therapy in posterior circulation strokes.

Local intra-arterial thrombolysis in a 4-year-old male with vertebrobasilar artery thrombosis

We report the case of a 4-year-old male with vertebrobasilar artery thrombosis for which he was treated with local intra-arterial urokinase 60 hours after onset of symptoms. Initially the patient had dysarthria and dysphagia. Brain magnetic resonance imaging (MRI) in a community hospital showed abnormalities in the pons, and vertebrobasilar artery thrombosis was suspected. The patient was transferred to the university hospital because of neurological deterioration. Just before thrombolysis, his physical examination revealed a downward ocular deviation, stretching of the arms, and spontaneous movements of the legs. Brain MRI showed recent ischaemia in the pons and caudal part of the mesencephalon, and magnetic resonance angiography showed occlusion of the basilar artery. Intra-arterial thrombolysis with urokinase (total dose 36 000U/kg) was performed 60 hours after onset of symptoms. After thrombolysis he was treated with heparin for 10 days, followed by aspirin. The patient recovered well. After 1 year he had only minor ataxia and performed all activities at school. Local vasculitis due to an infection with Borrelia burgdorferi was thought to be the cause of the local thrombosis. A review of the literature revealed 11 other case reports of successful local intra-arterial thrombolysis in children and adolescents with ischaemic stroke. This suggests that intra-arterial thrombolysis is feasible and safe in selected paediatric patients with ischaemic stroke.

Therapy of Acute Basilar Artery Occlusion

Background and Purpose— While intravenous recombinant tissue plasminogen activator (rt-PA) has been approved for acute stroke therapy within 3 hours, the optimum management of basilar artery occlusion (BAO) is still a matter of debate. We compared intraarterial thrombolysis with the combined bridging approach of intravenous abciximab and intraarterial thrombolysis with rt-PA (bridging therapy) in an observational, longitudinal, monocenter study.

Methods— Between 1998 and 2006, information for 106 patients with acute BAO were prospectively entered into a local database. Patients eligible for treatment received either intraarterial thrombolysis with rt-PA alone (intraarterial thrombolysis) or were treated with intravenous abciximab and intraarterial rt-PA (bridging therapy). Outcome parameters were recanalization of the basilar artery according to Trial in Myocardial Infarction criteria, survival, and reduction of severe disability and death at 3 months. Logistic regression was used to identify independent predictors for recanalization, survival, and clinical outcome.

Results— Of a total of 106 patients with confirmed BAO, 87 patients underwent subsequent angiography. Among those, 75 patients were identified who received the full treatment protocol. Patients in the bridging group had a better recanalization rate (83.7% vs 62.5%; P =0.03), a higher survival rate (58.1% vs 25%; P =0.01), and a better chance for an outcome with no or only mild to moderate disability (modified Rankin Scale score, 0–3; 34.9% vs 12.5%; P =0.02). Symptomatic intracerebral hemorrhage rates were comparable in both groups (14% in the bridging group vs 18.8%; P =0.41). Independent predictors for recanalization were age (OR, 0.95; 95% CI, 0.91–0.99), atrial fibrillation (OR, 6.53; 95% CI, 1.14–37.49), and bridging therapy (OR, 3.37; 95% CI, 1.02 to 11.18). Independent prognostic factors for outcome were Glasgow coma scale score at presentation (OR, 1.24; 95% CI, 1.03–1.45) and the combination of bridging therapy with successful recanalization (OR, 3.744; 95% CI, 1.04–13.43).

Conclusion— Bridging therapy for acute BAO with intravenous abciximab and intraarterial rt-PA appears to be safe and yields higher recanalization and improved survival rates, as well as an overall improved chance for a better outcome.

The basilar artery international cooperation study (BASICS)

Basilar artery occlusion is a rare cause of stroke with a high case fatality rate and an often poor clinical outcome among survivors. Our limited knowledge on the outcome in patients with basilar artery occlusion comes from small case series of selected patients.

STUDY AIM

The main purpose of the registry is to collect preliminary data that will help direct the design of a future clinical treatment trial. The target number of patients included is 500.

DESIGN

BASICS is a prospective, observational, multi-center, international registry of consecutive patients presenting with a symptomatic and radiologically confirmed basilar artery occlusion.

STUDY OUTCOMES

From November 2002 until December 2006 data have been collected on 400 patients, from 42 centers in 12 countries. Most patients were treated with IA therapy (55%), followed by antithrombotics (29%) and IV thrombolysis (6%). The overall mortality was 45%.

Intravenous thrombolysis with low-dose recombinant tissue plasminogen activator in central retinal artery occlusion

PURPOSE

To evaluate the beneficial effect of intravenous thrombolysis aiming at rapid restoration of blood flow during the early hours of a central retinal artery occlusion (CRAO).

DESIGN

Interventional case series.

METHODS

In the present study, we prospectively evaluated the visual outcome after thrombolytic treatment with low-dose (50 mg) rt-PA (recombinant tissue plasminogen activator) and concomitant intravenous heparinization in patients with acute CRAO, best-corrected visual acuity (BCVA) < or = 20/100, and onset of symptoms within 12 hours prior to treatment.

RESULTS

Twenty-eight patients (28 eyes) were included in this study. Final visual acuity was improved three or more lines in nine eyes (32%), stable in 18 (64%), and worse in one eye. Time to treatment < or = 6.5 hours was associated with a better gain of lines of vision (P = .004). Seven of 17 eyes (41%) that received thrombolytic treatment within the first 6.5 hours achieved a final BCVA > or = 20/50, compared to none in the subgroup of patients with onset to treatment >6.5 hours (P = .023). We observed no serious adverse events.

CONCLUSIONS

Our findings indicate that thrombolytic treatment with intravenous low-dose rt-PA is of value for an improved visual recovery in patients with acute CRAO, if administered within the first 6.5 hours after the onset of symptoms.

Endovascular interventions following intravenous thrombolysis may improve survival and recovery in patients with acute ischemic stroke: a case-control study

BACKGROUND AND PURPOSE

Since the introduction of recombinant tissue plasminogen activator (rtPA) into clinical practice in the mid 1990s, no adjunctive treatment has further improved clinical outcomes in patients with ischemic stroke. The safety, feasibility, and efficacy of combining intravenous (IV) rtPA with endovascular interventions has been described; however, no direct comparative study has yet established whether endovascular interventions after IV rtPA are superior to IV rtPA alone. A retrospective case-control study was designed to address this issue.

MATERIALS AND METHODS

Between 2003 and 2006, 33 consecutive patients with acute ischemic stroke and National Institutes of Health Stroke Scale (NIHSS) scores >/=10 were treated with IV rtPA in combination with endovascular interventions (IV plus intervention) at a tertiary care facility. Outcomes were compared with a control cohort of 30 consecutive patients treated with IV rtPA (IV only) at a comparable facility where endovascular interventions were not available.

RESULTS

Baseline parameters were similar between the 2 groups. We found that the IV-plus-intervention group experienced significantly lower mortality at 90 days (12.1% versus 40.0%, P = .019) with a significantly greater improvement in NIHSS scores by the time of discharge or follow-up (P = .025). In the IV-plus-intervention group, patients with admission NIHSS scores between 10 and 15 and patients </=80 years of age showed the greatest improvement, with a significant change of the NIHSS scores from admission (P = .00015 and P = .013, respectively).

CONCLUSIONS

In this small case-control study of patients with acute ischemic stroke and admission NIHSS scores >/=10, there was a suggestion of incremental clinical benefit among patients receiving endovascular interventions following standard administration of IV rtPA.

Acute basilar artery occlusion: topographic study of infarcts

OBJECTIVE

To determine the ischemic lesions distribution and extension of patients with basilar artery thrombosis by the means of magnetic resonance imaging (MRI).

METHODS

In 17 patients with thrombosis of the basilar artery, MRI was performed, including T2-weighted, magnetic resonance angiography (MRA) and diffusion-weighted imaging (DWI) sequences in the short-term phase (<48 hours). The shapes of ischemic lesions were obtained by graphic software and overlapped on a representative layer outline background.

RESULTS

The MRA showed basilar artery occlusion in all cases and the DWI revealed different patterns of ischemic lesions. Most patients showed multiple lesions within the posterior circulation territory. Lesions more often occurred in pontes, cerebellums and mesencephalons than medullas, thalami and occipital lobes. Basilar pons, cerebral crus and cerebellum hemisphere were more susceptible than pontine tegmentum, vermis, midbrain tegmentum and tectum.

CONCLUSIONS

When the basilar artery is occluded, basilar pons, cerebral crus and cerebellum hemisphere were most susceptible. The branches with smaller lumen of basilar artery, which are easier to be affected, are thought to be the cause of such a phenomenon.

Brain stem diffusion-weighted imaging lesion score: a potential marker of outcome in acute basilar artery occlusion

BACKGROUND AND PURPOSE

The benefit of recanalization in basilar artery occlusion (BAO) has been established. The baseline extent of brain stem damage may also influence the outcome. We investigated whether a baseline diffusion-weighted imaging (DWI) score may provide additional prognostic value in BAO.

MATERIALS AND METHODS

We analyzed baseline clinical and DWI parameters in consecutive patients treated with endovascular procedures for acute BAO. Brain stem DWI lesions were assessed by using a semiquantitative score based on arterial territory segmentation. Outcome at 3 months was dichotomized according to the modified Rankin Scale (mRS) as favorable (mRS, 0-2) or unfavorable (mRS, 3-6). Spearman rank correlation tests assessed the correlation between DWI and clinical variables. Univariate and multivariate logistic regression analyses were used to identify clinical and MR imaging predictors of outcome.

RESULTS

Twenty-nine patients were included. The brain stem DWI score (median, 3; range, 0-14) was correlated with the baseline National Institutes of Health Stroke Scale (NIHSS) score and the presence and length of coma (r = 0.67, 0.49, and 0.53, respectively; P < .01). Recanalization was achieved in 76%. A higher baseline NIHSS score (P = .02) and brain stem DWI score (P = .03), a lower Glasgow Coma Scale score (P = .04), and the presence of coma (P = .05) were associated with poor outcome in univariate analysis. Multivariate analysis showed that the brain stem DWI score was the only independent baseline predictor for clinical outcome (P = .026).

CONCLUSIONS

Baseline brain stem DWI lesion score is an independent marker of outcome in BAO.

Critical appraisal of medical devices in the management of cerebrovascular disease

Medical devices may revolutionize the management of acute ischemic stroke and prevention of recurrent events. By comparison with pharmaceuticals, the device approval process and subsequent application of these devices in stroke treatment is founded on a paucity of Class I evidence-based clinical trial data. Thromboembolectomy for acute stroke, stenting of cervical or cerebral arteries for stroke prevention, and percutaneous closure of patent foramen ovale for prevention or recurrent cerebral ischemia are being done with an ever-increasing frequency despite few, if any, randomized clinical trials to confirm the appropriateness of the interventions. The current basis, or lack thereof, for these interventions for cerebrovascular disease is therefore discussed. As such, a critical appraisal of the available clinical data does not support widespread use of medical devices at this time outside of well-designed clinical trials.

Extent of hypoattenuation on CT angiography source images predicts functional outcome in patients with basilar artery occlusion

BACKGROUND AND PURPOSE

Quantification of early ischemic changes (EIC) may predict functional outcome in patients with basilar artery occlusion (BAO). We tested the validity of a novel CT score, the posterior circulation Acute Stroke Prognosis Early CT score (pc-ASPECTS).

METHODS

Pc-ASPECTS allots the posterior circulation 10 points. Two points each are subtracted for EIC in midbrain or pons and 1 point each for EIC in left or right thalamus, cerebellum or PCA-territory, respectively. We studied 2 different populations: (1) patients with suspected vertebrobasilar ischemia and (2) patients with BAO. We applied pc-ASPECTS to noncontrast CT (NCCT), CT angiography source images (CTASI), and follow-up image by 3-reader consensus. We calculated sensitivity for ischemic changes and analyzed the predictivity of pc-ASPECTS for independent (modified Rankin Scale [mRS] score </=2) and favorable (mRS score </=3) outcome.

RESULTS

Of 130 patients with suspected vertebrobasilar ischemia, 72% (94) had posterior circulation stroke, 8% (10) transient ischemic attack, and 20% (26) nonischemic etiology. Sensitivity for ischemic changes was improved with CTASI compared to NCCT (65% [95% CI, 57% to 73%] versus 46% [95% CI, 37% to 55%], respectively). Pc-ASPECTS score on CTASI but not NCCT predicted functional independence (OR 1.58; P=0.005 versus 1.22; P=0.42, respectively). Of 46 patients with BAO, 52% (12/23) with CTASI pc-ASPECTS score >/=8 but only 4% (1/23) with a score <8 had favorable functional outcome (RR 12.1; 95% CI, 1.7 to 84.9). This difference was consistent in 21 patients with angiographic recanalization (RR 7.7; 95% CI, 1.1 to 52.1).

CONCLUSIONS

The CTASI pc-ASPECTS score may identify BAO patients unlikely to have a favorable outcome despite recanalization.

Guidelines for management of ischaemic stroke and transient ischaemic attack 2008

This article represents the update of the European Stroke Initiative Recommendations for Stroke Management. These guidelines cover both ischaemic stroke and transient ischaemic attacks, which are now considered to be a single entity. The article covers referral and emergency management, Stroke Unit service, diagnostics, primary and secondary prevention, general stroke treatment, specific treatment including acute management, management of complications, and rehabilitation.