On the threshold of an exciting new era for acute stroke diagnosis and treatment, the Third International Symposium on Thrombolytic Therapy in Acute Ischemic Stroke was held in Nara, Japan, in April 1994. The symposium brought together some 200 basic and clinical scientists for presentations and discussions of issues vital to the understanding of thrombolytic therapy. This volume compiles the major presentations of the symposium, with attention to applications of new diagnostic measures such as diffusion and perfusion MRI, contrast-enhanced transcranial Doppler and angioscopy. Other presentations examine the mechanisms of ischemia/reperfusion injury, hemorrhagic transformation, and reocclusion, with reviews of recent developments in thrombolytic agents. The proceedings of the symposium will be of special interest to researchers, physicians, and students in the fields of neurology, neurosurgery, and nuclear medicine, as well as those in pharmacology, critical care medicine, and related fields.

Over the last decade, interest in treatment of ischemic stroke has increased significantly. Perhaps the single most important feature of attempts to improve the outcome of stroke patients has been that the interventions be applied within the very early hours of stroke symptoms. This has spawned efforts to understand the vascular and neuronal responses to cerebral artery reperfusion experimentally. Important prospective clinical studies of thrombolysis in acute ischemic stroke have been completed, and large placebo-controlled, symptom-based studies are now underway worldwide. Here, we consider the central features of those studies, their experimental basis, and the future importance of adjunctive therapies to recanalization in focal brain ischemia acutely. Risks and benefits are discussed. This collection benefits from the opinions of experts and workers in this rapidly evolving and exciting field.

During the last decade scientists in both basic and clinical research have renew ed their interest in the potential role of thrombolytic therapy in the treatment of acute ischemic stroke. The reevaluation of this approach was kindled by our growing knowledge of the pathogenesis of thrombotic and embolic stroke and by the development of new thrombolytic agents. With no proven therapy for acute ischemic stroke available, the potential value of early pharmacologic recanalization of occluded vessels in the management of acute stroke patients - an approach that has been supported by animal experiments and a limited number of uncontrolled clinical pilot studies - is again under scrutiny. A sym posium on "Thrombolysis in Acute Cerebral Ischemia" was held in Heidel berg, Germany, in May 1990 to summarize and discuss the pathophysiological background for thrombolysis in acute ischemic stroke and the recent ex perimental and clinical experience with the new generation of thrombolytic agents. The editors are fortunate to be able to include authoritative manuscripts from almost all the speakers at the symposium. These include reports of work by the most active investigators in this challenging field. The editors wish to express their gratitude to all the contributors for the additional work they have undertaken. Additionally, we would like to thank Springer-Verlag, Heidelberg, for its generous assistance in the preparation and rapid publication of this volume. Heidelberg, August 1990 WERNER HACKE GREGORY J. DEL ZopPO MATTHIAS HIRSCHBERG Contents I."