Over the past few semesters a group of neurologists, neurophysiologists, and brain theorists in various departments of Tlibingen University have gathered periodically in an effort to review ideas and evidence on cerebel lar functions. At times, general solutions seemed close, when credit was given to various theoretical proposals advanced since the early days of cer ebellar physiology, however, it became clear in every case that a large part of the available facts refused to submit to the general ideas. As believers in the power of scientific discussion, we felt that the time was ripe for posing the problem of the cerebellum once more to a well articulated group of specialists that would include proponents of every disparate point of view. The sponsorship of the Max Planck Society and of the Deutsche Forschungsgemeinschaft, to whom we express our profound gratitude, made it possible to organize an international meeting in Septem ber, 1983. The aim of making new, even extravagant ideas palatable to each other was well accomplished by the participants. We trust that some of the ensuing excitement has been carried over into the printed version."

It is amazing to discover how little importance has been attached to narrow lumbar canal syndromes up to now. Though H. VERBIEST gave a very accurate description in 1949, the neurologist's and neurosurgeon's preoccupations were mainly focused on discal pathology, disregarding the problem of an exclusively bony origin in canalar stenosis. A. WACKENHEIM and E. BABIN have the merit of becoming aware of the impor tance and originality of this problem; they organized in the beautiful surround ings of the Bischenberg near Strasbourg, a postgraduate course, in which the most eminent European specialists in this field participated. I am very honored to have been asked to write the introduction to this mono graphy, which contains all the studies reported and commented on during this meeting. Before considering the problem from the various radiologic points of view, it is in my opinion indispensable to define the term "stenosis." We could not do so more accurately than by assuming the definition proposed by A. WACKENHEIM and E. BABIN and unanimously confirmed by all those who attented the session."

The rapid development of diagnostic and therapeutic procedures in the management of spinal angiomas has opened up new possibilities and provided better chances for the patients concerned. The greatest impetus to this pro gress was given by the introduction of selective and superselective spinal angiography, microsurgical technique, and embolization. These sophisticated techniques and the skill required for their use are far from being routine in the neurosurgical and neuroradiologic departments. In spite of the rarity of spinal angiomas, the application of the above-mentioned procedures is the prerequisite for improving early diagnosis and giving timely adequate treat ment. Delay in diagnosis and treatment are still the main cause of unsatisfac tory results. In the last 10 -20 years, several groups in Europe and the USA have done important and fundamental work in introducing and developing the diganos tic and therapeutic armamentarium. Based on the pioneering work of their teachers and the classic contribution of Wyburn - Mason in 1943, they simultaneously improved the morphologic, physiologic, and clinical basis of our knowledge. Although progress is going on and many problems have to be solved, the general principles of clinical diagnosis, operative treatment, and embolization have been laid down and are to be published in a special monograph on this topic."

Das vorliegende Buch enth{lt die Beitr{ge eines internatio- nalen Symposiumszum Thema "Stimulierte Hirndurchblutung." Vorgestellt werden zun{chst neue Erkenntnisse zur Regulation der Hinrdurchblutung. Im 2. Abschnitt kommen verschiedene Methoden zur Messung der Hirndurchblutung zur Sprache, die sowohl unter experimentellen als auch unter klinischen Be- dingungengetestet wurden. Es folgt ein Abschnitt, der ver- schiedene M-glichkeiten zur Stimulation der Hirndurchblutung aufzeigt. Im letzten Abschnitt wird aufdie Bedeutung der stimulierten Hirndurchblutungsmessung zur Bestimmung der ce- rebrovascul{ren Reservekapazit{ten hingewiesen. Dieser Para- meter hat nach den vorliegenden Untersuchungen klinisch- praktische Bedeutung, beispielsweise f}r die Indikations- stellung bei cerebrovascul{ren Eingriffen zur Isch{mie-Pro- phylaxe.

The blood-brain barrier is still not completely understood and therefore the subject of fascinating study. How are endogenous substances transported through the blood-brain barrier? What are the known therapeutic and toxic agents? How are they transported across cerebral microvessels? The discussion of these and other questions with far-reaching consequences for all neuroscientists can be found in this volume. This authoritative and up-to-date review of the blood-brain barrier gives a proper understanding of the topic. The experimental principles, the results of very recent research, as well as the implications that experimental research has for clinical treatment are thoroughly covered. Information is given on: - new findings based on classical physiological and pharmacological techniques, - results obtained from brain capillaries in vitro and in culture, - results obtained from the new scanning techniques (PET and MRI), - the immunology of the blood-brain barrier, - trace metal transport, - the pathological breakdown of the barrier and - the modification of drugs to increase their entry into the brain. Here is a source of information that is invaluable to specialists concerned with basic research in the neurosciences, with the design of neuropharmacological agents, with the radiological diagnosis of cerebral pathology or with the treatment of cerebral lesions!

This atlas offers a collection of EEG spectral analyses and their corresponding conventional recordings under anes thesio10gical procedures. The EEGs presented here were re corded on general surgical and gynecological patients during the last few years. Premedication, induction and maintenance of anesthesia, recovery the immediate postoperative period, and intensive care are covered. Techniques for operating the necessary equipment and artefacts relevant to the routine clinical use of EEG are briefly outlined. Typical examples of characteristic EEGs are presented at the beginning of each chapter, followed by illustrations of deviations from the norm showing the great variety of anesthesiologically induced changes of cerebral function. The description of each EEG course is assessed in relation to clinical parameters. Sometimes no satisfactory interpreta tion can be made, because many physiological and patho physiological causes of alterations in cerebral function are unknown. Time and again it proves impossible to estimate wether deviations from the norm have their origin in cerebral changes or are secondary to extracerebra1 disturbances. The atlas comprises a complete survey in itself, but it can also be seen as a supplement to the book The Electroenceph alogram in Anesthesia by I. Pich1mayr, U. Lips, and H. Kunkel (Springer, 1983), in which detailed lists of references are quoted that are omitted here."

Technological improvements in neurosurgery are disussed. The use of surgical lasers, ultrasound aspirators, bipolar coagulator and operative microscopes for surgery of deep-seated neoplasms and vascular malformations is discussed. Intraoperative monitoring, chronotherapy, chronic neurostimulation and stereotactic interstitial irradiation are covered and indications for interventional neuroradiology are reviewed.

'Samii's Essentials in Neurosurgery' contains selected papers written by internationally recognized contributors who were trained by Professor Madjid Samii in Hannover, Germany. The main topics deal with cutting-edge technology in neurosurgery, skull-base surgery, and specific peripheral nerve, spine, and vascular surgeries. The texts and a wealth of illustrations review and reinforce guidelines on the diagnosis and management of situations that readers are likely to encounter in everyday practice. This book will be of great interest to neurosurgeons, neurologists, ENT surgeons, neuroradiologists, and neurophysiotherapists."

We have witnessed a remarkable development during the past 10 years in the development of extra-intracranial anastomosis to revascularize the brain. Initially, the intention was to create ameans of performing embolectomy in small corticaI arteries after cardiac surgery. Gradually a plan was conceived to form an extra-intracranial bypass(10) to treat inaccessible lesions of the carotid and vertebral arteries as weIl as tumors and giant aneurysms that involved these arteries. The basic techniques and principles of microvascular sur- gery, which had been refined over 30 years on peripheral ar- teries(1-7, 9) were applied in 1966 to the intracerebral arteries of dogs(4). The arterial patehing and suturing were successful, while extra-intracraniallong bypasses were a constant failure. This was attributed to the damage that was inevitably inflicted on the vasa vasorum of the autogenous graft during dissec- tion(9). This situation posed a dilemma until eventually the idea of Pool and Potts(8) was adopted and an anastomosis was performed on a dog between the superficiaI temporaI artery and a cortical branch. Because of the vesseIs' small size and the doubts regarding its capacity for improving the circulation, the procedure was performed with a certain amount of apprehen- sion. It was a pleasant surprise, therefore, to discover that it was possible to attain a high rate of patency. If the middle cerebral artery was us ed and was isolated from its carotid in- flow, an even higher rate was achieved.

This volume covers, in a logical sequence, the brain neuroscience which underpins current management of malignant brain tumours. Cellular and molecular studies are considered, as well as current concepts of histopathological classification and grading. The clinical manifestations and natural history of these tumours is set in context by a discussion of the pathophysiology of intracranial mass lesions. Special attention is given to low-grade and childhood tumours. The more common cerebral gliomas and cerebral metastases are also examined. Diagnostic imaging methods are described and the differential diagnosis of benign and malignant tumours is explored. The final chapters are devoted to conventional and innovative methods, along with the results, of treatment by surgery, radiation, chemotherapy and immunotherapy.

In this age when we are witnessing a veritable explosion in new modalities in diagnos tic imaging we continue to have a great need for detailed studies of the vascularity of the brain in patients who have all types of cerebral vascular disease. Much of the understanding of cerebral vascular occlusive lesions which we developed in the last two decades was based on our ability to demonstrate the vessels that were affected. Much experimental work in animals had been done where major cerebral vessels were obstructed and the effects of these obstructions on the brain observed pathologically. However, it was not until cerebral angiography could be performed with the detail that became possible in the decades of the '60 's and subsequently that we could begin to understand the relationship of the obstructed vessels observed angiographically to the clinical findings. In addition, much physiologic information was obtained. For instance, the concept ofluxury perfusion which is used to describe non-nutritional flow through the tissues was observed first angiographically although the term was not used until LASSEN described it as a pathophysiological phenomenon observed during cerebral blood flow studies with radioactive isotopes. The concept of embolic occlusions of the cerebral vessels as against thrombosis was clarified and the relative frequency of thrombosis versus embolism was better understood. The concept of collateral circulation of the brain through so-called meningeal end-to end arterial anastomoses was vastly better understood when serial angiography in obstructive cerebral vascular disease was carried out with increasing frequency."

More than 40 years ago British and German neurosurgeons met in Berlin and Breslau to exchange their experiences, to strengthen their friendly bonds, and to enjoy the attractions of both cities and their surroundings. In 1960 a joint meeting of the Dutch and German societies took place in Rotterdam by invitation of the Nederlandse Vereniging van Neurochirurgen. All who attended this meeting thankfully remember the great hospitality during these unforgettable days. In 1970, by courtesy of the Society of British Neurological Surgeons, German neurosurgeons had the pleasure to become acquainted with the great tradition of British sciences at one of the most famous places during the meeting in Cambridge. These impressions were deepened by visits to other famous sources of British scientific tradition during the European Congress in Oxford in 1975. The critical distance sometimes necessary towards our own discipline is implicit in the major themes of this meeting. Complications following shunting procedures for hydrocephalus have been discussed on the basis of the results of a cooperative study of some German neurosurgical departments. The second main topic was problems and diagnostic errors in computer tomography. The papers presented contain critical considerations about the findings obtained by this method, as well as on its possibilities and limitations. German neurosurgeons felt deeply indebted to their British and Dutch colleagues and wanted to return their kindness at this joint meeting in Berlin. We hope that all participants will retain pleasant memories of the days in this city.

Increasing specialisation in pathology reflects the progressive changes in medical practise. The advent of a specialist with a new interest in a hospital or clinic may present the pathologist with a need to extend his or her knowledge to be able to work closely with the clinical practi tioner in order to provide adequate clinical care. Some sub-specialisations are long established, such a one is neu ropathology. However, an exclusive specialist practise is generally con fined to neurosurgical centres and much neuropathology is of necessity, executed by geneni.l pathologists. The areas covered by this volume are those which are commonly managed by the generalist. Professor Adams' account of how the skull and brain should be examined here will give confidence to many by defining a good technique and the careful description of various kinds of vascular injury lesions resulting from raised intracranial pressure will help to clarify repeated difficulty. More subtle forms of damage are also considered in detail. Professor Weller provides a detailed account of how the central nervous system may be examined in a way which permits all of us to prepare material which will allow adequate investigation of central nervous system disease and the proper examination of peripheral nerves. This chapter will become a "handbook" and will be of interest to those in training and established practitioners. Muscle biopsy is also dealt with; this is an area of investigative concern for many gener alists. The role of that singular neuropathological technique is very clearly emphasized.

The book on Processes of Recovery from Neural Trauma contains the proceedings of an international symposium which was sponsored by the Weizmann Institute of Science and was held in June 1984 in Israel. One of the central problems in neurobiology and clinical neurology are the processes which underlie the ability of the nervous system to recover from damage. Neurons of the mammalian nervous system cannot be replaced once the generative embryonic period has ended. Thus, recovery after trauma is limited by the degree to which regeneration of damaged neural processes is possible and by the capac ity of uninjured neurons to form new synaptic contacts or to use their existing ones more effectively. The lack of successful axon regeneration in the central nervous system is the reason for the permanent damage and the very limited recovery of function seen in victims of traumatic injury. Over the past few years, research on neural trauma has witnessed significant progress, resulting from interdis ciplinary research carried out in an increasing number of laboratories throughout the world. Accordingly, the book includes reports on the progress made in the forefront of research in this field. We hope that in addition to being a source of new informa tion, readers of the book will be stimulated to work and to generate new ideas and research strategies in this field of research.

Ever since I began my training in internaI medicine and subsequently in neurology, I have been interested in subarachnoid haemorrhage and indeed chose this topic as a subject of study for my Doctorate in Medicine. It was because the information derived from a retrospective study of 312 patients proved to be so interesting that I published a monograph on the subject 30 years ago. My first reaction on reading this splendid book by my former coHeagues in Newcastle, Mr. Sengupta and Dr. McAllister, was one of realisation of the extent to whjch knowledge about the condition' and principles of management have been transformed. This splendidly comprehensive volume carefully reviews the earlier literature, analyses the anato micaI, pathophysiologicaI and clinical features of the condition in consummate detail and goes on to consider in depth all of those issues relating to investigation and medical and surgical management which continue to present chaHenges to neurologists and neuro-surgeons alike. When I began my personal study, angiography had still to be introduced as a routine method of radiologicaI diagnosis in many centres in the U .K. and we were Iargely dependent upon dinicaI methods of diagnosis and assessment. How interesting it is to see that now, very properly, computerised tomography (CT scanning) takes precedence as an initiaI diagnostic instrument over angiography, and that lumbar puncture, once thought to be obligatory for diagnosis, is being used Iess and less since its dangers were fully appreciated."

"Tips and pearls on the latest developments on endoscopic approaches to skull base and brain surgery from experts around the globe"

Ideal for both otolaryngologisthead and neck surgeons and neurosurgeons, " Transnasal Endoscopic Skull Base and Brain Surgery: Tips and Pearls" gathers together in one comprehensive volume invaluable advice from world-renowned authorities on state-of-the-art endoscopic technologies and techniques.

Each succinct chapter begins with a summary of key takeaway points and features an easily accessible outline format. After uniquely detailed coverage of macroscopic and endoscopic anatomy, the expert authors discuss the most up-to-date surgical approaches integrated with key information on technologic advances, such as 3D reconstruction and navigation. Clearly labeled illustrations demonstrate each step of the various procedures. The book closes with practical guidance on postoperative care and guidelines for avoiding and managing the potential complications encountered in these complex surgeries.

Features: In-depth information on endoscopic surgical procedures for the paranasal sinuses, anterior skull base, and the craniocervical junction Easy-to-reference bullet-points in each chapter distill the renowned authors vast experience Step-by-step surgical descriptions cover the full spectrum of skull base pathology Stunningly detailed illustrations, including more than 500 in full-color, enhance the text throughout

This landmark work will improve the accuracy and precision of every surgeon and fellow in otolaryngologyhead and neck surgery and neurosurgery who deals with this delicate anatomic region.

The cerebello-pontine angle has always posed a challenge to the neurosurgeon, the otoneurosurgeon, and the neuroradiologist. Angle masses which are very small and difficult to detect frequently produce symptoms, but may remain silent while growing to exceptional size. The neuroradiologist must have firm knowl edge of the clinical manifestations of the diverse angle lesions in order to tailor his studies to the patients' needs. The majority of angle lesions are benign; thus successful surgery has the potential for complete cure. Angle lesions typically arise in conjunction with vital neurovascular structures, and often displace these away from their expected positions. Large lesions may attenuate the vestibulocochlear and facial nerves and thin them over their dome. Since the nerves often remain functional, the surgeon then faces the need to separate the tumor from the contiguous nerve, with preservation of neurological function. Depending on the exact location and extension of the lesion, resection may best be attempted via otologic or neurosurgical approaches. The neuroradiologist must determine - precisely -the presence, site, size, and extension( s) of the lesion and the displacement of vital neurovascular structures as a guide to selecting the line of surgical attack. Since the arteries, veins, and nerves that traverse the angle are fine structures, the neuroradiologist must perform studies of the highest quality to do his job effectively."

A quarter of a century has elapsed since Nils Lundberg published his thesis "Continuous Recording and Control of Ventricular Fluid Pressure In Neurosurgical Practice." This publication, more than any other, propelled continuous monitoring of intracranial pressure from the status of a research tool to become an integral part of neurosurgical intensive care, with wide application in the management of patients with head injuries, intracranial haemorrhage, brain tumours and disorders of the CSF circulation. At the same time, experimental studies by Langfitt and others stimulated investigations of the relationships between intracranial pressure and cerebral blood flow, intracranial pressure volume relationships and studies of the formation and absorption of CSF. By 1972, Mario Brock had realised the extent of the interest in intracranial pressure research and organised the First International Symposium on Intracranial Pressure in Hanover in that year. This was the start of a series of highly successful meetings, subsequently held in Lund (1974), Groningen (1976), Williamsburg (1979) and Tokyo (1982), the proceed ings of which have been published as a uniform series of books. In each of these volumes the up to date status of research and clinical application of intracranial pressure measurement has been presented in a concise yet comprehensive way. The present volume contains the proceedings of the Sixth International Intracranial Pressure Symposium that was held in Glasgow, Scottland, from June 9th to 13th, 1985."

The two International Symposia on Spinal Cord Monitoring, held in Tokyo in 1981 [Homma S, Tamaki T (eds) (1984) Fundamentals and clinical appli- cation of spinal cord monitoring. Saikon Publishing, Tokyo] and Erlangen in 1984, were remarkable in that they stimulated a gathering of electro- encephalographic, neurophysiological, orthopaedic, neurosurgical, anaes- thetic and pathological practitioners, presenting experimental, clinical and surgical experiences. The factor held in common was an understanding of the need to reduce the incidence and severity of iatrogenic neurological im- pairment associated with certain surgical and radiographic procedures. In the past there has been a tendency for the study of human evoked poten- tials (EPs) to be regarded as an end in itself, or at best a discipline which can be of limited assistance in certain problems of neurological diagnosis. Symposia such as these serve the valuable function of opening electro- physiological eyes to the problems to which EP techniques might usefully be devoted in other medical spheres. They also help those who practise electrophysiology as an adjunct to their speciality to comprehend such of the more complex properties of EPs as are relevant to their particular interests. The title of the Symposia and of this volume arose as a result of an his- torical accident. The pioneers of intraoperative neuronal monitoring were mostly surgeons specialising in the correction of spinal deformities or the removal of tumours.

The human skull has many functions. The largest component of the skull, the neurocranium, protects and insulates the brain. It comprises the dome-shaped vault or calvaria, obviously a protective structure, and the more complex cranial base, which gives the vault a massive foundation and also houses the organs of hearing, balance, and smell. The facial skeleton, or splanchnocranium, encloses the upper airway and the mouth. Chewing, the cQ-ordinated action ofthe jaws and teeth, is a function of the facial skeleton. The orbits, formed from both calvarial and facial bones, house the eyes and their accessory muscles. The'skull also provides skeletal support for the muscles which affect speech and facial expression. It is largely by these that people communicate and display their emotions. Personality is judged on speech and on facial appearances, by conscious or subconscious aesthetic comparisons with cultural ideas-and prejudices. So the shape of the skull has, or can have, profound emotional significance.

It is estimated that the functionally significant body of knowledge for a given medical specialty changes radically every 8 years. New specialties and "sub-specialization" are occurring at approximately an equal rate. Historically, established journals have not been able either to absorb this increase in publishable material or to extend their readership to the new specialists. International and national meetings, symposia and seminars, workshops, and newsletters suc cessfully bring to the attention of physicians within developing spe cialties what is occurring, but generally only in demonstration form without providing historical perspective, pathoanatomical corre lates, or extensive discussion. Page and time limitations oblige the authors to present only the essence of their material. Pediatric neurosurgery is an example of a specialty that has de veloped during the past 15 years. Over this period neurosurgeons have obtained special training in pediatric neurosurgery and then dedicated themselves primarily to its practice. Centers, Chairs, and educational programs have been established as groups of neuro in different countries throughout the world organized surgeons themselves respectively into national and international societies for pediatric neurosurgery. These events were both preceded and fol lowed by specialized courses, national and international journals, and ever-increasing clinical and investigative studies into all aspects of surgically treatable diseases of the child's nervous system."

It is estimated that the fU, nctionally significant body of knowledge for a given medical specialty changes radically every 8 years. New specialties and "sub-specialization" are occurring at approximately an equal rate. Historically, established journals have not been able either to absorb this increase in publishable material or to extend their readership to the new specialists. International and national meetings, symposia and seminars, workshops and newsletters successfully bring to the attention of physicians within developing specialties what is occurring, but generally only in dem onstration form without providing historical perspective, pathoanatomical correlates, or extensive discussion. Page and time limitations oblige the authors to present only the essence of their material. Pediatric neurosurgery is an example of a specialty that has developed during the past 15 years. Over this period, neurosurgeons have obtained special training in pediatric neurosurgery, and then dedicated themselves primarily to its practice. Centers, Chairs, and educational programs have been established as groups of neurosurgeons in different countries throughout the world organized themselves respectively into national and international societies for pediatric neurosurgery. These events were both preceded and followed by specialized courses, national and international journals, and ever-increasing clinical and investigative studies into all as pects of surgically treatable diseases of the child's nervous system."

There are two important reasons for commencing this new series of publi cations entitled "Advances and Technical Standards in Neurosurgery": 1. the lack of any organized common European postgraduate training system for young neurosurgeons and 2. the language barriers, which impede the exchange of neuro surgical findings in Europe more than in other parts of the world. The fact that the English language is well on the way to becoming the international medium at European scientific conferences is a great asset in terms of mutual understanding. Therefore the Editors have decided to publish all contributions in English, regardless of the native language of the authors. All contributions are submitted to the entire editorial board before publi cation of any volume. Our series is not intended to compete with the publications of original scientific papers in other neurosurgical journals. Our intention is, rather, to present fields of neurosurgery and related areas in which important recent advances have been made. The contributions will be written by specialists in the given fields and will constitute the first part of each volume."

There are two important reasons for publishing this new series entitled "Advances and Technical Standards in Neurosurgery" 1. the lack of anyor ganized common European postgraduate training system for young neurosurgeons and 2. the language barriers, which impede the exchange of neurosurgical findings in Europe more than in other parts of the world. The fact that the English language is well on the way to becoming the international medium at European scientific conferences is a great asset in terms of mutual understanding. Therefore the Editors have decided to publish all contributions in English, regardless of the native language of the authors. All contributions are submitted to the entire editorial board before publi cation of any volume. Our series is not intended to compete with the publications of original scientific papers in other neurosurgical journals. Our intention is, rather, to present fields of neurosurgery and related areas in which important recent advances have been made. The contributions are written by specialists in the given fields and constitute the first part of each volume. In the second part of each volume, we publish detailed descriptions of standard operative procedures, furnished by experienced clinicians; in these articles the authors describe the techniques they employ and explain the advantages, difficulties and risks involved in the various procedures. This part is intended primarily to assist young neurosurgeons in their postgraduate train ing. However, we are convinced that it will also be useful to experienced, fully trained neurosurgeons."

Sleep plays an important role in the history of the neurosciences. On Easter Monday in 1920, Otto Loewi was awakened in the night by a dream in which he conceived of neurotransmitters communicating across the synapse. He quickly made notes, but in the morning he could not understand his scribbles. The following night, the dream came again. He wrote down his thoughts more carefully and, the next day, conducted the crucial experiment that launched modern neu rophysiology (Koelle, 1986). Since the beginning of the modern era of sleep research in the 1950s, we have used the principles of neurotransmission to explore the regulation of sleep. Without resorting excessively to comments on blind men and elephants, however, it is fair to say that the phenomena of sleep and waking can be approached from many perspectives. Among other things, sleep is a process that can be described electri cally, an experience that so far defies physiological measurements, and a social behavior. In this book, I have tried to describe the physiology and pharmacology of sleep (Part I) and to relate them to clinical sleep disorders (Part II). Having neither the skill nor the grandiosity of Rous seau, I have made no attempt to write an encyclopedia of all that is known on the subject. Rather, I think of this book as more of a snap shot, giving a picture of where we are, and it is hoped, a history of how we got here."