Neurological recovery after decompressive craniectomy for massive ischemic stroke

INTRODUCTION

Decompressive craniectomy has demonstrated efficacy in reducing morbidity and mortality in critically ill patients with massive hemispheric cerebral infarction. However, little is known about the patterns of functional recovery that exist in patients after decompressive craniectomy, and controversy still exists as to whether craniotomy and infarct resection ("strokectomy") are appropriate alternatives to decompression alone. We therefore used functional magnetic resonance imaging (f-MRI) to assess the extent and location of functional recovery in patients after decompressive craniectomy for massive ischemic stroke.

METHODS

f-MRI was obtained in three patients with massive nondominant cerebral infarction who had undergone decompressive craniectomy for severe cerebral edema 13 to 26 months previously. Brain activation was triggered by hand-gripping or foot- movement tasks. Imaging results were combined with periodic clinical follow-up to determine the extent of neurological recovery.

RESULTS

Activation of the contralateral hemisphere was seen in the sensorimotor cortex, premotor, and supplementary motor areas. Lesser activation patterns were seen in equivalent regions of the infarcted hemisphere. Peri-infarct activation foci were seen in two of the three patients, but no activation occurred within the area of infarction as defined by the initial stroke seen on diffusion-weighted MRI. All three patients demonstrated some corresponding neurological improvement.

CONCLUSION

After massive hemispheric cerebral infarction requiring decompressive craniectomy, patients may experience functional recovery as a result of activation in both the infarcted and contralateral hemispheres. The evidence of functional recovery in peri-infarct regions suggests that decompression alone may be preferable to strokectomy where the risk of damage to adjacent nonischemic brain may be greater.

[Long-term results of operative treatment of the vertebro-basilar syndrome]

In case of changes occurring within the extracranial sections of the common and internal carotid artery the operative procedure has become a generally accepted surgical method. Another reason of brain ischemia is the vertebro-basilar insufficiency caused by external pressure on the vertebral artery in a channel formed by transverse processes of cervical vertebrae. The author presents the clinical experience with 54 cases that have been treated surgically from 1994 to 2003 due to the above mentioned reasons. In all patients an anastomosis between the distal vertebral artery and external carotid artery gave good or very good results.

Decompressive craniectomy and mild hypothermia reduces infarction size and counterregulates Bax and Bcl-2 expression after permanent focal ischemia in rats

Both mild hypothermia (MH) and decompressive craniectomy (CE) have been shown to have neuroprotective effects in brain ischemia. We investigated a possible effect of MH and a combination of CE and MH (CE + MH) on the changes of infarction size, DNA fragmentation, and immunoreactivities for Bcl-2 and Bax after 24 h of permanent middle cerebral artery occlusion (MCAO) in rats. For the estimation of ischemic brain injury, we calculated the infarct size of the MCA region at 24 h after the MCAO. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick labeling (TUNEL) staining was performed for the detection of DNA fragmentation. Immunoreactivities for Bcl-2 and Bax were stained. Infarction size after permanent MCAO was significantly reduced by CE+MH treatment (P < 0.01). Infarction size did not change significantly by application of MH alone (P > 0.05). TUNEL staining was remarkably reduced both in MH-treated animals and in CE + MH-treated animals. Immunoreactivity for Bcl-2 was greatly induced both in MH-treated animals and in CE + MH-treated animals. Induction of immunoreactivity for Bcl-2 was obviously inhibited both in MH-treated animals and in CE + MH-treated animals. It suggests that temporary MH delays infarct evolution and ameliorates neuron apoptosis but does not significantly reduce definite infarction size. CE + MH not only ameliorates neuron apoptosis but also remarkably reduces infarction size.

Transplantation of hNT neurons into the ischemic cortex: Cell survival and effect on sensorimotor behavior

Cell transplantation offers a potential new treatment for stroke. Animal studies using models that produce ischemic damage in both the striatum and the frontal cortex have shown beneficial effects when hNT cells (postmitotic immature neurons) were transplanted into the ischemic striatum. In this study, we investigated the effect of hNT cells in a model of stroke in which the striatum remains intact and damage is restricted to the cortex. hNT cells were transplanted into the ischemic cortex 1 week after stroke induced by distal middle cerebral artery occlusion (dMCAo). The cells exhibited robust survival at 4 weeks posttransplant even at the lesion border. hNT cells did not migrate, but they did extend long neurites into the surrounding parenchyma mainly through the white matter. Neurite extension was predominantly toward the lesion in ischemic animals but was bidirectional in uninjured animals. Extension of neurites through the cortex toward the lesion was also seen when there was some surviving cortical tissue between the graft and the infarct. Prolonged deficits were obtained in four tests of sensory-motor function. hNT-transplanted animals showed a significant improvement in functional recovery on one motor test, but there was no effect on the other three tests relative to control animals. Thus, despite clear evidence of graft survival and neurite extension, the functional benefit of hNT cells after ischemia is not guaranteed. Functional benefit could depend on other variables, such as infarct location, whether the cells mature, the behavioral tests employed, rehabilitation training, or as yet unidentified factors.

Human cord blood CD34+ cells and behavioral recovery following focal cerebral ischemia in rats

The present study investigated effects of human umbilical cord blood derived CD34+ cells on sensorimotor, cognitive, and histological outcome in rats following focal cerebral ischemia. Halothane anesthetized adult male Wistar rats were subjected to transient or permanent occlusion of the middle cerebral artery (MCAO) followed by intravenous administration of CD34+ cells (5 x 10(5) or 2 x 10(6)) after 24 h recovery. The beam-walking and cylinder tests were used to assess sensorimotor function, and Morris water-maze examined cognitive performance during a 25 day follow-up period. Subsequently, rats were perfused for measurement of infarct volumes and detection of CD34' cells in the brain by immunohistochemistry (MAB1281). MCAO rats showed minor or no spontaneous recovery in sensorimotor function during the follow-up. The recovery profile was similar in MCAO controls and in MCAO rats that received CD34+ cells, although CD34+ cells seemed to improve the use of impaired forelimb. There was also a trend toward improved water-maze performance by CD34+ cells in transient MCAO rats. Infarct volumes assessed from Nissl-stained sections on postoperative day 25 did not differ between the experimental groups. MAB 1281-positive cells were not detected in the brain of MCAO rats that received CD34+ cells. The present study suggests that CD34+ cells might improve functional outcome in MCAO rats after systemic administration, but do not significantly provide neuroprotection.

[Efficacy of surgical and therapeutic methods of repeated carotid ischemic stroke prophylaxis]

Comparative efficacy of surgical and therapeutic methods of repeated ischemic stroke prophylaxis at the patients with clinical symptoms of acute brain ischemia and carotid stenosis less 70% was analyzed. Three-year period of follow-up demonstrated that at the patients who have undergone carotid endarterectomy the repeated ischemic events were seen only at 4 (3.9%), and in the group of therapeutic prophylaxis--at 57 (52.7%). Carotid endarterectomy permits to reduce relative risk of repeated ischemic stroke from 0.77 in therapeutic prophylaxis to 0.07 in surgical treatment. Antiaggregant therapy after surgery is mandatory. Prolonged administration of Clopidogrel permits to reduce restenosis and thrombotic complication rate.

Enhanced brain angiogenesis in chronic cerebral hypoperfusion after administration of plasmid human vascular endothelial growth factor in combination with indirect vasoreconstructive surgery

OBJECT

Vascular endothelial growth factor (VEGF) is a secreted mitogen associated with angiogenesis. The conceptual basis for therapeutic angiogenesis after plasmid human VEGF gene (phVEGF) transfer has been established in patients presenting with limb ischemia and myocardial infarction. The authors hypothesized that overexpression of VEGF using a gene transfer method combined with indirect vasoreconstruction might induce effective brain angiogenesis in chronic cerebral hypoperfusion, leading to prevention of ischemic attacks.

METHODS

A chronic cerebral hypoperfusion model induced by permanent ligation of both common carotid arteries in rats was used in this investigation. Seven days after induction of cerebral hypoperfusion, encephalomyosynangiosis (EMS) and phVEGF administration in the temporal muscle were performed. Fourteen days after treatment, the VEGF gene therapy group displayed numbers and areas of capillary vessels in temporal muscles that were 2.2 and 2.5 times greater, respectively, in comparison with the control group. In the brain, the number and area of capillary vessels in the group treated with the VEGF gene were 1.5 and 1.8 times greater, respectively, relative to the control group.

CONCLUSIONS

In rat models of chronic cerebral hypoperfusion, administration of phVEGF combined with indirect vasoreconstructive surgery significantly increased capillary density in the brain. The authors' results indicate that administration of phVEGF may be an effective therapy in patients with chronic cerebral hypoperfusion, such as those with moyamoya disease.

Therapy of Severe Ischemic Stroke: Breaking the Conventional Thinking

Large hemispheric infarcts must be recognized in the emergency department as a life-threatening condition that requires prompt and massive intervention. After stabilization of the airway, breathing, and circulation, the initial diagnostic work-up and transfer to a neurointensive care unit should not be delayed. Today several new therapeutic options can be offered. Surgical decompression seems to be effective in lowering increased intracranial pressure, preventing transtentorial herniation and reducing mortality in patients with malignant middle cerebral artery infarction. Another option may be therapeutic hypothermia, which has been found to be neuroprotective in animal models, as well as in clinical studies after cardiac arrest. Experience in stroke patients suggest that hypothermia may offer a new approach for the treatment of acute cerebral ischemia.

Unique anomalous origin of the left anterior cerebral artery

We present the case of an anomalous origin of the left anterior cerebral artery (ACA) from the supraclinoid segment of the right internal carotid artery. Because of improved imaging quality, anomalies of the ACA-anterior communicating artery (AComA) complex are increasingly recognized on transaxial images. Although most of these anomalies are incidental findings of little clinical significance, some ACA-AComA complex anomalies are clinically significant. Recognition of these anomalies may be instrumental in developing a differential diagnosis or for improved surgical planning.

Extracranial—intracranial bypass in the treatment of occlusive cerebrovascular disease and intracranial aneurysms in the United States between 1992 and 2001: a population-based study

Object. The authors assessed the results of extracranial—intracranial (EC—IC) bypass surgery in the treatment of occlusive cerebrovascular disease and intracranial aneurysms in the US between 1992 and 2001 by using population-based methods.

Methods. This is a retrospective cohort study based on data from the Nationwide Inpatient Sample (Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality, Rockville, MD). Five hundred fifty-eight operations were performed at 158 hospitals by 115 identified surgeons. The indications for surgery were cerebral ischemia in 74% of the operations (2.4% mortality rate), unruptured aneurysms in 19% of the operations (7.7% mortality rate), and ruptured aneurysms in 7% of the operations (21% mortality rate). Overall, 4.6% of the patients died and 4.7% of the patients were discharged to long-term facilities, 16.4% to short-term facilities, and 74.2% to their homes. The annual number of admissions in the US increased from 190 per year (1992–1996) to 360 per year (1997–2001), whereas the mortality rates increased from 2.8% (1992–1996) to 5.7% (1997–2001).

The median annual number of procedures was three per hospital (range one–27 operations) or two per surgeon (range one–21 operations). For 29% of patients, their bypass procedure was the only one recorded at their particular hospital during that year; for these institutions the mean annual caseload was 0.4 admissions per year. For 42% of patients, their particular surgeon performed no other bypass procedure during that year. Older patient age (p < 0.001) and African-American race (p = 0.005) were risk factors for adverse outcome. In a multivariate analysis in which adjustments were made for age, sex, race, diagnosis, admission type, geographic region, medical comorbidity, and year of surgery, high-volume hospitals less frequently had an adverse discharge disposition (odds ratio 0.54, p = 0.03).

Conclusions. Most EC—IC bypasses performed in the US during the last decade were performed for occlusive cerebrovascular disease. Community mortality rates for aneurysm treatment including bypass procedures currently exceed published values from specialized centers and, during the period under study, the mortality rates increased with time for all diagnostic subgroups. This technically demanding procedure has become a very low-volume operation at most US centers.

Advances in thrombolytics and mechanical devices for treatment of acute ischemic stroke

Stroke is a leading cause of death and disability. Recently, there have been advances in the treatment of acute ischemic stroke aimed at re-establishing blood flow to the affected area in an effort to save the ischemic penumbra surrounding the area of infarction. This is achieved by the use of thrombolytics intravenously or intra-arterially. The use of mechanical devices facilitates the function of pharmacological agents used in addition to minimizing the associated risks. In this review, we first discuss the therapeutic potentials and strategies employed in using different thrombolytics in management of acute ischemic stroke. Subsequently, we discuss the recent advances and therapeutic applications of mechanical devices in this field.

Brain stem ischemia from intracranial dural arteriovenous fistula: Case report

BACKGROUND

Intracranial dural arteriovenous fistulas (AVFs) with spinal perimedullary venous drainage are rarely reported, but most of the patients initially have presented with myelopathy or subarachnoid hemorrhage. This is the first report of the intracranial dural AVF patient who presented with brain stem infarction.

CASE DESCRIPTION

A 38-year-old woman experienced nausea and vomiting with an acute onset, followed by vertigo. Magnetic resonance imaging showed ischemic lesion in the medulla oblongata, and she was then sent to our hospital. On admission, she had nystagmus, swallowing difficulties, Homer syndrome, and right hemiparesis and hemisensory disturbance. Cerebral angiography revealed dural AVF draining into spinal perimedullary veins at the left transverse-sigmoid sinus. The patient was treated by transvenous embolization under local anesthesia. A microcatheter proceeded to the left sigmoid sinus via the internal jugular vein, and embolization of the sinus was performed using coils without complications. The patient's swallowing difficulties improved over a few days after the embolization, and one month later, there remained only a slight mild hemiparesis and hemisensory disturbance. Six months after the onset, there was no ischemic lesion in the brain stem on magnetic resonance imaging.

CONCLUSIONS

In this case, we showed the possibility of brain stem infarction, caused by the intracranial dural AVF.

Statins Are Associated With Better Outcomes After Carotid Endarterectomy in Symptomatic Patients

BACKGROUND AND PURPOSE

Statins have been associated with a reduction in mortality from noncardiac surgery. This study aimed to determine whether statin use on admission to hospital for carotid endarterectomy was associated with a reduction of in-hospital adverse outcomes.

METHODS

Data describing patient characteristics, surgical indication, statin treatment, and in-hospital outcomes of death, ischemic stroke or death and cardiac outcomes were collected from a chart review of all patients (3360) undergoing carotid endarterectomy in Western Canada from January 2000 to December 2001. Outcomes of patients on statins versus those not on statins were compared using logistic regression to account for differences in patient characteristics, and propensity score methods to account for factors influencing patient allocation to statins.

RESULTS

Eight hundred and fifteen of 2031 symptomatic patients and 665 of 1252 asymptomatic patients were on a statin at the time of hospital admission. Statin use by symptomatic patients was associated with reduced in-hospital mortality and in-hospital ischemic stroke or death, but not in-hospital cardiac outcomes (adjusted odds ratio 0.25 [CI, 0.07 to 0.90], 0.55 [CI, 0.32 to 0.95], 0.87 [CI, 0.49 to 1.54], respectively). The improvement in outcomes was robust when tested using propensity score matching. This association was not seen in asymptomatic patients on statins (adjusted odds ratio, in-hospital mortality 0.54 [CI, 0.13 to 2.24]; in-hospital ischemic stroke or death 1.34 [CI, 0.61 to 2.93]; in-hospital cardiac outcomes 1.37 [CI, 0.73 to 2.58]).

CONCLUSIONS

These findings are suggestive of a protective effect of statin therapy in symptomatic patients pre-treated at the time of carotid endarterectomy, though this needs confirmation in a randomized controlled trial.

Moyamoya disease associated with Graves disease: special considerations regarding clinical significance and management

OBJECT

In moyamoya disease (MMD), ischemic events are usually precipitated by activities associated with hyperventilation or physical strain. The authors report on four patients with a rare combination of Graves disease-associated thyrotoxicosis and MMD, whose cerebrovascular ischemic events occurred while in a thyrotoxic state. The clinical correlation between MMD and Graves' thyrotoxicosis, and outcome after surgical intervention are described.

METHODS

Four young women, ages 22 to 25 years, presented with profound cerebrovascular ischemic accidents. They had clinical and radiological features consistent with the diagnosis of MMD and were in the active thyrotoxic state of Graves disease. To prevent a future ischemic event, patients underwent superficial temporal artery-middle cerebral artery anastomosis combined with encephalomyosynangiosis or encephaloduroarteriosynangiosis after normalization of their hormonal conditions. All patients have been neurologically stable since revascularization procedures and lead a normal daily life. In patients with MMD, cerebrovascular ischemic events may be precipitated by thyrotoxicosis. One possible pathomechanism of cerebrovascular ischemic aggravation in the thyrotoxic state may be a hemodynamic compromise induced by an excessive increase in the cerebral metabolism and oxygen demand over the compensation of the cerebral blood flow deficit through collateral supply in MMD.

CONCLUSIONS

Surgical revascularization after optimal control of thyrotoxicosis is thought to be an appropriate treatment in patients with MMD concurrent with Graves disease for the prevention of further ischemic events, especially in those with impaired cerebral perfusion and cerebral ischemic symptoms.

Use of multimodal MRI and novel endovascular therapies in a patient ineligible for intravenous tissue plasminogen activator

BACKGROUND AND PURPOSE

Options are limited for individuals who present to the ED within 3 hours of ischemic stroke onset, but who are deemed ineligible for intravenous thrombolysis. Multimodal MRI has been shown to be of great help in identifying stroke patients with large areas of at risk "penumbral tissue", who may gain from the use of novel endovascular therapies. We report a patient who twice benefited from this management approach, in the setting of hemorrhagic risk following successive ischemic strokes.

CASE DESCRIPTION

The patient is a 78 year old male who experienced acute ischemic stroke on 2 separate occasions 5 months apart, and for whom perceived contraindications to appropriate thrombolytic therapy administration led to the successful use of different endovascular therapies at each encounter. Furthermore, following mechanical clot retrieval during the second encounter, the high intensity signal area noted on the baseline diffusion weighted imaging (DWI) in the posterior circulation territory, was almost completely resolved on the day 7 post-procedure MRI.

CONCLUSIONS

To our knowledge, this is the first reported case of reversal of a DWI abnormality in the posterior circulation territory.

Thyrocervical trunk—external carotid artery bypass for positional cerebral ischemia due to common carotid artery occlusion

✓ Medically refractory positional cerebral ischemia (PCI) and concomitant orthostatic hypotension associated with chronic common carotid artery (CCA) occlusion are rare. In this technical report, the authors describe an extracranial bypass in which the thyrocervical trunk was used as a donor vessel to treat three cases of CCA occlusion with PCI. Postoperatively, although orthostatic hypotension remained, ischemia-related symptoms resolved in all three patients and long-term graft patency was demonstrated. It is possible to treat cerebral ischemia due to CCA occlusion with extracranial bypass surgery. In these patients, the thyrocervical trunk proved to be a suitable donor vessel for the reconstitution of blood flow within the external carotid artery.

Safety and efficacy of mechanical embolectomy in acute ischemic stroke: results of the MERCI trial

BACKGROUND AND PURPOSE

The only Food and Drug Administration (FDA)-approved treatment for acute ischemic stroke is tissue plasminogen activator (tPA) given intravenously within 3 hours of symptom onset. An alternative strategy for opening intracranial vessels during stroke is mechanical embolectomy, especially for patients ineligible for intravenous tPA.

METHODS

We investigated the safety and efficacy of a novel embolectomy device (Merci Retriever) to open occluded intracranial large vessels within 8 hours of the onset of stroke symptoms in a prospective, nonrandomized, multicenter trial. All patients were ineligible for intravenous tPA. Primary outcomes were recanalization and safety, and secondary outcomes were neurological outcome at 90 days in recanalized versus nonrecanalized patients.

RESULTS

Recanalization was achieved in 46% (69/151) of patients on intention to treat analysis, and in 48% (68/141) of patients in whom the device was deployed. This rate is significantly higher than that expected using an historical control of 18% (P<0.0001). Clinically significant procedural complications occurred in 10 of 141 (7.1%) patients. Symptomatic intracranial hemorrhages was observed in 11 of 141 (7.8%) patients. Good neurological outcomes (modified Rankin score < or =2) were more frequent at 90 days in patients with successful recanalization compared with patients with unsuccessful recanalization (46% versus 10%; relative risk [RR], 4.4; 95% CI, 2.1 to 9.3; P<0.0001), and mortality was less (32% versus 54%; RR, 0.59; 95% CI, 0.39 to 0.89; P=0.01).

CONCLUSIONS

A novel endovascular embolectomy device can significantly restore vascular patency during acute ischemic stroke within 8 hours of stroke symptom onset and provides an alternative intervention for patients who are otherwise ineligible for thrombolytics.

Emergency carotid artery stent placement in patients with acute ischemic stroke

BACKGROUND AND PURPOSE

An effective intervention has not yet been established for patients with acute ischemic stroke who present with serious neurologic symptoms due to occlusion or a high-grade stenosis of the internal carotid artery (ICA). The aim of our retrospective study was to investigate the feasibility, safety, and efficacy of emergency carotid artery stent placement to improve neurologic symptoms and clinical outcome.

METHODS

Of 896 consecutive patients with acute ischemic stroke who were admitted to our institution within 7 days of onset from July 2000 to June 2003, 17 patients (1.9%) with occlusion or a high-grade stenosis of the ICA underwent emergency carotid artery stent placement. We reviewed their records for neurologic outcome, per the National Institutes of Health Stroke Scale (NIHSS) score, before and at 7 days after stent placement; clinical outcome, per the modified Rankin Scale score (mRS), at 90 days; frequency of procedure-related complications within 30 days; and recurrence rate of ipsilateral ischemic stroke within 90 days.

RESULTS

Carotid lesions were dilated completely in all patients. Median NIHSS scores before emergency stent placement and at 7 days were 12 and 5, respectively, showing significant improvement (P < .01, Wilcoxon rank sum test). Ten patients (59%) had favorable outcomes (mRS score 0-1) at 90 days. Irreversible complications occurred in two patients (12%): distal embolism in one and intracerebral hemorrhage in the other. No ipsilateral ischemic stroke recurred.

CONCLUSION

Emergency carotid artery stent placement can improve the 7-day neurologic outcome and may improve the 90-day clinical outcome in selected patients with ischemic stroke.

Simultaneous carotid endarterectomy and coronary artery bypass surgery in Canada

Stroke neurologists are commonly asked to review patients who require coronary artery bypass grafting (CABG) but who also have comorbid severe carotid stenosis; such patients may be offered simultaneous carotid endarterectomy (CEA). In Canada, 0.51% of CABG procedures were combined CEA-CABG. The adjusted stroke and death rate was 2.67-fold greater in the combined CEA-CABG group compared to CABG alone. Randomized trials of the combined procedure are needed.