Choose an application

• Reference Manager
• EndNote
• RefWorks (Direct export to RefWorks)

The ischemic penumbra was initially defined by Symon, Lassen and colleagues in the 1970s as an area of brain tissue with inadequate blood flow to maintain electric activity of neurons but adequate blood flow to preserve the function of the ion channels. This area of tissue, receiving enough blood to survive but not enough to function, often surrounds or abuts the irreversibly damaged core in ischemic stroke. It was shown that if blood flow could be restored to this area of marginal perfusion, the tissue could survive and function again, and growth of the core could be prevented. Based on seminal PET studies, penumbra or "penumbral tissue" eventually took on a subtly different meaning - the area of brain that is destined to progress to infarct unless blood flow is restored within a particular time window. The penumbra thus became the target for all acute stroke interventions - to preserve viability of the tissue and restore function. New imaging techniques, including diffusion and perfusion MRI and CT perfusion, were developed to rapidly identify individuals with penumbra, who were thought to be the best candidates for aggressive interventions to restore blood flow, particularly beyond the licensed time-window for IV thrombolysis. However, most clinical trials have failed to establish the usefulness of identifying candidates for treatment in this way using pre-specified protocols and primary endpoints. These trials have used different and sometimes unvalidated thresholds of hypoperfusion as well as irreversible infarct and various definitions of significant penumbra (or mismatch between irreversible infarct and hypoperfused, but salvageable tissue), and reanalysis of their data using more refined image processing showed post-hoc positivity. They have also evaluated outcome in a variety of ways, with few studies measuring the direct effect of restoring blood flow on the function of the penumbral tissue. Therefore, important remaining questions include how to define, characterize, and image the penumbra in acute stroke to achieve the greatest reliability and validity for what we want to measure, and whether this concept, so defined, provides an optimal target for stroke therapy using state-of-the-art trial design.

Acute ischemic stroke. --- Computer tomography perfusion. --- Penumbra. --- Cerebrovascular disease.

Choose an application

• Reference Manager
• EndNote
• RefWorks (Direct export to RefWorks)

Intracranial endovascular use of Balloon and Stent has expanded significantly. This issue will highlight the use today with its advantages and limitations, focusing on most recent advancements. This discussion will also emphasize the improvements made towards understanding the disease process itself, no longer limiting the practice to devices alone. Wide-necked intracranial aneurysms (IA) were originally thought to be either untreatable or, at the least, significantly challenging to treat by endovascular means due to the risk of coil protrusion into the parent vessel. Through recent advancements, balloon-remodeling technique (BRT) has been introduced. Additionally, stents specifically designed for intracranial use have progressively allowed these lesions to be treated endovascularly. BRT and stent-assisted coiling technique (SACT) were utilized for sidewall aneurysms, however both techniques have gained experience and technical development to treat bifurcated, complex-shaped, wide-neck aneurysms. Therefore, this article will review the inherent benefits and drawbacks to BRT as well as SACT. The Chinese healthcare system has had significant improvements, however, this nation of 1.4 billion continues to faces challenges towards stroke treatment. Intracranial atherosclerosis is a prominent cause of stroke in various populations worldwide, including China, and has been noted to be the most common vascular lesion in stroke patients. Furthermore, symptomatic atherosclerotic stenosis of an intracranial artery results in a 14% risk of recurrent ischemia. This article will summarize the challenges of risk factor modification and secondary stroke prevention by defining optimal strategies. After the publication of clinical trial SAMMPRIS, neurologists began to hesitate referring patients to interventionists. With intracranial artery stenosis being an important cause of stroke, we have designed a prospective study and a multicenter RCT to verify the effectiveness of percutaneous transluminal angioplasty and stenting (PTAS). This article will report the current situation, considerations for further clinical work in the field of intracranial artery stenosis in China and worldwide. Angioplasty used in the setting of symptomatic intracranial stenosis has been performed for more than two decades. The technique has gradually become refined, randomized data is lacking to show the benefits compared to medical treatment. Nevertheless, medical treatment with severe symptomatic stenosis (>70%) continues to have high rates of stroke and death. This paper will review the history of angioplasty, current trends, and future uses of this treatment technique. Despite impressive recanalization rates in ischemic stroke treatment, the clinical improvement rate has remained unchanged. In the last 20 years, less than 50% of patients demonstrated improvement resulting in the concept of the 50% barrier. This article will discuss the lack of optimal patient selection criteria and present the hypothesized capillary index score (CIS) on IMS I, II, III to surpass the 50% barrier. Expansion of devices capable of mechanically interrupting clots found in occluded vessels has occurred in recent years. However, evidence is lacking to prove their advances over thrombolytic interventions that carry fewer risks. This article will review data from IMS III in order to answer this extremely fundamental question.

Neurology. --- Stroke --- Management. --- Prevention. --- Medicine --- Nervous system --- Neuropsychiatry --- Apoplexy --- Brain --- Cerebral circulation disorders --- Cerebral vascular accident --- Cerebrovascular accident --- Cerebrovascular disorders --- Cerebrovascular syndrome --- CVA (Disease) --- Neglect (Neurology) --- Diseases --- Blood-vessels --- stent assisted coiling technique (SACT) --- Intracranial aneurysms --- balloon remodeling technique (BRT) --- intracranial endovascular --- Acute ischemic stroke --- intracranial vasospasms --- Subarachnoid Hemorrhage --- percutaneous transluminal angioplasty and stenting (PTAS) --- capillary index score (CIS) --- intracranial stenosis --- Cerebrovascular disease