Medical imaging is an important topic and plays a key role in robust diagnosis and patient care. It has experienced an explosive growth over the last few years due to imaging modalities such as X-rays, computed tomography (CT), magnetic resonance (MR) imaging, and ultrasound. This book focuses primarily on model-based segmentation techniques, which are applied to cardiac, brain, breast and microscopic cancer cell imaging. It includes contributions from authors working in industry and academia, and presents new material.

For more than 35 years the Swiss Society of Neuropathology has organiseditstraditionalInternationalWinterMeeting.Themainaimofthis venue is to bring together neuropathologists and clinicians as well as neuroscientistsinterestedindiseasemechanisms.TheXVIIIthInternational WinterMeeting washeld inMarch 2000 in St. Moritz, Switzerland. The topicofthe2000Meetingwas"NeuropathologyandGeneticsofDementia." Aprogrammeofinvitedplenarylecturesofhigheducationalvalueaswellas platform andposterpresentations given by manyparticipantscoveredthe broadspectrumofdementingdisorders.Encouragedbythehighstandardof the meeting, and probably also influenced by the advent of a new Millenniumwedecided, togetherwithKluwerAcademiclPlenumPublishers, topublishtheProceedingsofthe2000Meetinginthepresentbook. The increaseofthe agedpopulation challenges social and health care systemsinindustrializedsocieties.Maintenanceofhealthandautonomyinto oldage isakeyfactor, andtheautonomyandindependenceofoldpersons crucially depend on mental health. However, neurodegenerative disorders accompanied bydementiaaffect 5-10%ofindividualsoverthe ageof65, and for the age group between 65 and 95 the prevalence of cognitive dysfunction doubles every 5 years. With this challenge in mind, Rossor discusses the clinical syndrome of dementia which encompasses an enormousvarietyofunderlyingdisorders. Over the last few years it has become apparent that many neurodegenerative disorders are characterised by protein misfolding and aberrant polymerization and may therefore be viewed as "aggregation proteopathies." Among them a substantial subsetofdementing disorders, either with or without motor dysfunction, are characterised by abundant v VI Preface neuronaland/orglialaccumulationofhyperphosphorylatedtauprotein.The molecular parametersofthese "tauopathies" are reviewed by Delacourte. Therecentdiscoverythatmutationsofthetaugenearecausativeforfamilial formsoffrontotemporaldementiaandParkinsonism(FTDP-17)broughtthe "taupathway"and the"tauopathies"tothecentrestage.Thisextraordinary breakthroughwillbecoveredbySpillantiniandGoedert.Thereisincreasing evidence that argyrophilic grain disease is much more frequent in older patients than previously thought. Tolnay et al. are reviewing recent contributionstothepathologyofthislate-onsetdementingdisorderinwhich ofamyloidbetadeposits, isalmost taupathology, inthealmosttotalabsence exclusivelyrestricted to the limbic lobe and the amygdala. Schultzet al. report an intriguing age-related progression of neuronal and glial tau pathologyinbaboonsthusrenderingthe baboonapotentialprimatemodel forage-relatedhuman"tauopathies." Gotzetal. introducetransgenicmice expressingmutated human tau as valuable animal models for reproducing formationofneuro-andglialfibrillarylesions.

This volume is divided into three sections. Section I deals with factors that regulate the development and maturation of T cells and B cells and lymphocyte traffic. The significance of C-kit, Bcl-6, IL-7, and Vav in the development of T and B lymphocytes is discussed. A role of lymphotoxins and VAP-I in trafficking of leucocytes is reviewed. Finally, the trafficking and homing characteristics of T cell and B cell subsets, and the regulation of these processes during the immune response, is presented. Section II discusses various aspects of naive and memory T cell biology, including clonal expansion, reprogramming of genes including those encoding cytokines and cytotoxic granules, changes in the expression of cell surface proteins involved in cell-cell adhesion, homing of naive and memory T cells, the role of MHC and cytokines in the maintenance of naive and memory T cells, and the characterization and differentiation of virus-specific memory T cell heterogeneity in mice and humans. Novel methods of visualization of immune cells and immune systems are reviewed in Section III.

The study of atherosclerosis centered since the first decade of the present century on etiology and pathogenesis. In fact, the studies of the military academy of medicine in St. Petersburg have opened the way of inducing atherosclerosis in animals. Pathogenesis of atheroma has been studied since then in humans and animals naturally prone to the development of the disease and by a variety of dietary and other procedures. The various experimental studies allowed science to evaluate the relative importance of different factors (genetic, dietary, hormonal, pharmacological. mechanical, circulatory, etc.) in atherogenesis. Epidemiological studies as well as biochemical plasma lipid and lipoprotein estimations coupled with light microscopic, histo chemical and electron microscopic investigations decreased the gap between observations on the human and experimental animal research. The enormous literature covering this field allows the intelligent reader to formulate a comprehensive concept regarding etiological factors and pathogenesis of atherosclerosis. Its impact on pre ventive and curative medicine was however limited in scope."

The title of this monograph, Brain Tumor Research and Therapy, is the name of the Conference itself, which had its inaugural meeting in the United States in 1975 andhas since progressed to the international scale. In Japan, the first conference ofits kind was organized by Dr. Takao Hoshino and me and was held at Nikko in 1980, hence its name, the Nikko Conference on Brain Tumor Research and Therapy. Though it started as a small, closed meeting, the conference has grown considerably, and in 1992 it was reorganized as the Japanese Conference on Brain Tumor Research and Therapy and was opened to all neurosurgeons and neuropathologists interested in the study of brain tumor problems and who are participating in this field. The main purpose of the Conference on Brain Tumor Research and Therapy is the candid and informed discussion of the most up-to-date developments in basic re search and clinical treatment of brain tumors. The 3rd Japanese Conference on Brain Tumor Research and Therapy was held at Nasu (Tochigi Prefecture), Japan, in No vember 1994. It was a great honor to welcome many distinguished guests from over seas who kindly attended each session and made valuable contributions.

The past 20 years have seen a surge of research into colorectal cancer, which is a reflection of the need to improve our methods of treating patients suffering from this increasingly common form of cancer. Greater knowledge of the basic mechanisms involved in colorectal carcinogenesis is an essential prerequisite to improvements in cancer prevention. In this volume the editors have brought together an impressive list of experts to cover the epidemiology, pathophysiology, morphology and basis for new diagnostic and therapeutic approaches to early detection and prevention. This broad scientific approach provides the reader with up-to-date review of our current state of knowl edge of colorectal carcinogenesis and indicates how this information can be used to generate more research and create new opportunities for diagnosis and treatment. This is a book of knowledge and ideas, some of them still at the stage of theoretical interest, but others with practical potential for the care of patients. I recommend it to those who have a research interest in colorectal carcinogenesis, as well as to readers who wish to know just how far medical scientists have progressed in their efforts to achieve the ideal of cancer prevention."

This two-volume work contains the full text of the oral and poster presentations and the general discussion at the round table discussion of the Second International Conference on Alzheimer's and Parkinson's Diseases: Basic and Therapeutic Strategies, held at the Kyoto Park Hotel in Kyoto, Japan, on November 6-10, 1989. The First Conference was held at the Aviya Sonesta Hotel in Eilat, Israel, on March 24-27, 1985. , The record of this First Conference was published by Plenum Press in 1986 as Volume 29 in Advances in Behavioral Biology, under the title "Alzheimer's and Parkinson's Diseases: Strategies for Research and Development." We are happy that the comprehensive texts of the oral and poster presentations of the Second Conference could again be published within the framework of this series. Since the First Conference in 1985, rapid progress has been made in both basic and therapeutic aspects of these diseases. About 700 scientists from allover the world participated in the Second Conference, and 300 papers were presented in oral and poster sessions. Many people and organizations have helped to organize this multi disciplinary international conference and hence have contributed to the scientific quality of these two volumes. We thank the members of the organizing committee, the organizations that provided financial support, and the contributing scientists for their enthusiastic participation.

More than ten years have elapsed since the publication of the first edition of Tumors and Tumorlike Lesions of Bone and Joints in 1981. During this period significant progress has been made in diagnosis, and particularly in staging and treatment of bone tumors. In most centers, limb-sparing surgery has replaced the more radical ablative surgery, with or without preoperative chemotherapy. This became possible due to the introduction and increased application of newer high-quality imaging techniques (CT and MRI) and in particular the use of new cytomorphologic methods of diagnosis, especially immunohisto chemistry. These advances in diagnosis and treatment have been reflected by the publication of new editions of several important text books, since their authors - pathologists, orthopedic surgeons, and radiologists - felt the necessity of updating their works in recent years. However, in these publications different criteria of classification were adopted. The number of cases compiled at the Latin American Registry of Bone Pathology increased from 4913 primary bone tumors and more than 1100 tumorlike lesions at the time of publication of the first edition of this book, to 5274 bone tumors and 1665 tumorlike lesions by the end of December 1985, when I finished my work as head of the Registry and occupied the positions of Professor of Orthopedic Pathology at St. Louis University Medical Center and Distinguished Visiting Professor at Rush-Presbyterian-St. Luke's Medical Center in Chicago.

Practicing specialists in pathology, laboratory medicine, and obstetrics comprehensively summarize the latest scientific findings and their experiences in the use and interpretation of laboratory testing in patients who are pregnant or experiencing recurrent pregnancy loss. Topics of interest include the effects of normal physiological changes on test results, test selection for diagnosis, changes in reference ranges, monitoring the pregnant patient, new technologies, and the limitations of laboratory testing. The authors not only clearly explain currently used test methods and technologies for the nontechnical reader, but also provide comprehensive details for laboratory professionals. The comprehensive appendix that compiles published normal reference ranges by first, second, and third trimester consttitutes an excellent resource for professionals caring for pregnant women.

Information analysis centers were developed to help the scientist and practitioner cope with the ever increasing mass of published and unpublished information in a specific field. Their establishment resulted from a further extension of those pressures that had brought about the formation of the specialized primary journal and the abstracting services at the turn of the century. The information analysis center concept was greatly advanced by the 1963 report of the President's Science Advisory Committee Panel on Science Information. This report stated: " . . . scientific interpreters who can collect relevant data, review a field, and distill information in a manner that goes to the heart of a technical situation are more help to the overburdened specialist than is a mere pile of relevant docu ments. " Such specialized information centers are operated in closest possible contact with working scientists in the field. These centers not only furnish information about ongoing research and dis seminate and retrieve information but also create new information and develop new methods of infor mation analysis, synthesis, and dissemination. The continually expanding biomedical literature produced by scientists from the world's laboratories, research centers, and medical centers led the National Institute of Neurological Diseases and Stroke in 1964 to initiate a National Neurological Information Network of specialized centers for neurological information. The Centers are designed to bring under control and to promote ready access to important segments of the literature."

The Italian Study Group on Cardiomyopathies organized in Florence in April 1997, eight years after the first successful meeting, the second international symposium devoted to "Advances in Cardiomyopathies". In these years exceptional progress has been made in the field of heart muscle diseases, in clinical research as well as in molecular biology, molec- ular genetics., pathophysiology and treatment. Many of these advances were presented and discussed in Florence by a distinguished team of international experts. Hypertrophic cardiomyopathy was addressed in ten papers; in the first one Seidman reported the results obtained by the use of molecular genetic tech- niques which showed that hypertrophic cardiomyopathy is a heterogeneous disorder caused by different mutations of different genes and discussed the clinical role and significance of genetic testing. Original data regarding the natural history and prognosis of symptomatic patients were obtained in the Italian multicentric study (Cecchi, Lazzeroni), while Baroldi discussed the clinico-pathologic spectrum of the disease in severely symptomatic patients treated with heart transplantation. Sudden death in the young (Basso), the identification and management of high risk patients (Elliott), the clinical importance and the problems of detec- tion of ischemia (Camici) were deeply discussed as well as the indications and results of different types of treatment: medical, surgical, DDD pacing (Spirito, Betocchi, Schoendube).

, 1m Kleinsten die wirkliche Wahrheit gibt graBen Gedanken erst Klarheit" KARL THOMAS Each year sees the publication of hundreds of reports of experimental work on the lymphatic tissue, yet morphological studies of the cells involved can be counted on the fingers of one hand. Furthermore, anyone who tries to identify these cells by morphological criteria is accused of sophistry and hair splitting, whereas it is accounted scientifically correct and unbiased to speak of "lymphoid cells," "blast cells" etc. Not so many years ago things were different: there were too many names and too many classifi cations and everyone backed his particular fancy. People thought of cells in terms of rigid classes, nothing then being known about the transformability of mononuclear blood cells. Today we must look for the middle way: cells should be named and defined according to morpho logical criteria but their transformation potential should be borne in mind. Once the cells are analysed and subdivided, it will be simple enough to set up proper classifications afterwards. This book arose out of the conviction that there should be more criteria and more information available on the morphology of human lymphoreticular cells; previously such information had been restricted by the difficulty of the special hematological and cytochemical staining methods."

This volume contains the proceedings of an International Symposium on `Second Messenger Systems - Molecular, Cellular and Behavioural Aspects', which was held at Tobago on June 16-17, 1994. The interaction of an extracellular agonist (First Messenger) with its plasma membrane receptor leads to the transmission of a signal across the cell membrane and results in the production and/or activation of other signalling molecules (Second Messengers). These Second Messengers control the action of many protein kinases and protein phosphatases and so lead to cellular responses. Although the biochemical basis of the transduction of signals in the main signalling systems in eukaryotic cells is probably largely known, intensified research is ongoing in the following areas: the discovery of specific substrates for many protein kinases, elucidation of the biological significance of the differential tissue expression and heterogeneity of many signalling proteins, and the unravelling of diverse interactions (such as signal potentiation, synergism, antagonism and neuronal co-transmission) between signalling systems. As knowledge from such studies accumulates, it is becoming clear that the `cross talk' interactions between signalling systems are important features of dynamic cell regulation. This volume is designed to summarize some aspects of the current work on various Second Messenger Systems and the integration of signals with respect to plasma membrane receptors. Second Messenger generation and degradation, protein kinase and phosphatase, cell cycle control, and cellular learning and memory.

Ataxia-telangiectasia or A-T is a fatal progressive neurological disease of children. The symptoms indicate disruptions in the development of such diverse body parts as cerebellum, thymus and chromosomes. The patients are unduly sensitive to ionizing radiation, immunodeficient, and a third of them develops cancer. All of this stems from defects of a single gene. Provided here is an up-to-date review of all important work in thefield. A wide spectrum of topics is covered, namely genetics, chromosome 11 mapping, radiobiology, complementation, heterozygote identification, clinical variants, biochemistry, and treatment of A-T.

As an addition to the European postgraduate training system for young neurosurgeons, we began to publish in 1974 this series of Advances and Technical Standards in Neurosurgery which was later sponsored by the European Association of Neurosurgical Societies. This series was first discussed in 1972 at a combined meeting of the Italian and German Neurosurgical Societies in Taormina, the founding fathers of the series being Jean Brihaye, Bernard Pertuiset, Fritz Loew and Hugo Krayenbuhl. Thus were established the principles of European co operation which have been born from the European spirit, flourished in the European Association, and have been associated throughout with this senes. The fact that the English language is now the international medium for communication at European scientific conferences is a great asset in terms of mutual understanding. Therefore we have decided to publish all contri butions in English, regardless of the native language of the authors. All contributions are submitted to the entire editorial board before publication of any volume for scrutiny and suggestions for revision. 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.

The Nato Advanced Study Institute on Humoral Immunity in Neurological Diseases became possible thanks to the active help of many people. I will not mention our colleagues at the neuroche- mical laboratory of the Born-Bunge Foundation : it was our common job. But I wish to thank : - the Nato and Dr. Kester for their aid, support and gene- rosity, - the Belgian Ministry of Foreign Affairs and Secretary-ge- neral Mr. Grandry for their help and assistance in esta- blishing valuable contacts with many foreign countries, - the Belgian Ministry of Culture for their grant, - the National Fund for Scientific Research and the Belgian Society of Neurology for their financial support. Substantial help came from the Universitaire Instelling Ant- werpen : not only financiall~ but by allowing members of their staff to assist us 'in many ways. The Belgian Friends of the Weizmann Institute and the Belgian Medical Care for Israel helped invite some participants, and many firms made a contribution to our organization. To all of them our warmest thanks.

This two-volume work contains the full text of the oral and poster presentations and the general discussion at the round table discussion of the Second International Conference on Alzheimer's and Parkinson's Diseases: Basic and Therapeutic Strategies, held at the Kyoto Park Hotel in Kyoto, Japan, on November 6-10, 1989. The First Conference was held at the Aviya Sonesta Hotel in Eilat, Israel, on March 24-27, 1985. The record of this First Conference was published by Plenum Press in 1986 as Volume 29 in Advances in Behavioral Biology, under the title "Alzheimer's and Parkinson's Diseases: Strategies for Research and Development." We are happy that the comprehensive texts of the oral and poster presentations of the Second Conference could again be published within the framework of this series. Since the First Conference in 1985, rapid progress has been made in both basic and 'therapeutic aspects of these diseases. About 700 scientists from allover the world participated in the Second Conference, and 300 papers were presented in oral and poster sessions. Many people and organizations have helped to organize this multi disciplinary international conference and hence have contributed to the scientific quality of these two volumes. We thank the members of the organizing committee, the organizations that provided financial support, and the contributing scientists for their enthusiastic participation. These two volumes follow the same publishing philosophy as the volume derived from the First Conference. They span a broad spectrum of topics and bridge preclinical and clinical concepts related to these diseases.

Traditional textbooks in molecular biology deal with basic science and are not readily applicable to the medical setting. Most medical textbooks that include a mention of molecular pathology in the clinical setting are limited in scope and assume that the reader already has a working knowledge of the basic science of molecular biology. Other texts emphasize technology and testing procedures without integrating the clinical perspective. There is an urgent need for a text that fills the gap between basic science books and clinical practice. In the Molecular Pathology Library series the basic science and the technology is integrated with the medical perspective and clinical application. Each book in the series is divided according to neoplastic and non-neoplastic diseases for each of the organ systems traditionally associated with medical subspecialties.

Each book in the series is organized to provide (1) a succinct background of the essential terminology, concepts and technology of molecular biology, (2) an overview of the broad application of molecular biology principles to disease and (3) specific application of molecular pathology to the pathogenesis, diagnosis and treatment of neoplastic and non-neoplastic diseases specific to each organ system. These broad section topics will be broken down into succinct chapters, averaging about 15 to 20 pages each, to cover a very specific disease entity. The chapters will be written by established authorities on the specific topic from academic centers around the world. In one book, diverse subjects are included that the reader would have to pursue from multiple sources in order to have a clear understanding of the molecular pathogenesis, diagnosis and treatment of specific diseases. Attempting to hunt for the full information from basic concept to specific applications for a disease from the varied sources is time-consuming and frustrating. By providing this quick and user-friendly reference, understanding and application of this rapidly growing field is made more accessible to both expert and generalist alike.

As books that bridge the gap between basic science and clinical understanding and practice, the Molecular Pathology Series serves the basic scientist, the clinical researcher and the practicing physician or other health care provider who require more understanding of the application of basic research to patient care, from "bench to bedside." This series is unique and an invaluable resource. These books will be indispensable to physicians and health care providers in multiple disciplines as noted above, to residents and fellows in these multiple disciplines as well as their teaching institutions and to researchers who increasingly must justify the clinical implications of their research.

The philosophy of this NATO Advanced Research Workshop and the monograph it has yielded is that if you put a small number of very talented and creative scientists of different backgrounds and documented accomplishments together in a cloistered place for a few days to consider a very important and timely topic, many new ideas will be generated. The keynote of this conference was the Future. By this we mean the expected future developments of highly reliable sequential quantitative measurements of atherosclerotic plaque size and components in living human subjects. Some of the best minds and the most experienced and talented individuals at the leading edges of imaging of arteries were involved; some of the best scientists and students of the atherosclerotic plaque and its components participated; and some of the leading investigators of the cell biology or, as we call it in the USA, the pathobiology of atherosclerosis, contributed important new information. All of these individuals were actively involved in the conference and each obviously had carefully prepared and was able to communicate effectively.

Information analysis centers were developed to help the scientist and practitioner cope with the ever increasing mass of published and unpublished information in a specific field. Their establishment resulted from a further extension of those pressures that had brought about the formation of the specialized primary journal and the abstracting services at the turn of the century. The information analysis center concept was greatly advanced by the 1963 report of the President's Science Advisory Committee Panel on Science Information. This report stated: " . . . scientific interpreters who can collect relevant data, review a field, and distill information in a manner that goes to the heart of a technical situation are more help to the overburdened specialist than is a mere pile of relevant docu ments. " Such specialized information centers are operated in closest possible contact with working scientists in the field. These centers not only furnish information about ongoing research and dis seminate and retrieve information but also create new information and develop new methods of infor mation analysis, synthesis, and dissemination. The continually expanding biomedical literature produced by scientists from the world's laboratories, research centers, and medical centers led the National Institute of Neurological Diseases and Stroke in 1964 to initiate a national Neurological Information Network of specialized centers for neurological information. The Centers are designed to bring under control and to promote ready access to important segments of the literature."

The Intemational Meeting on Vitamin B6 and Carbonyl Catalysis took place on Capri, Italy from 22nd to 27th May 1994 and was organized in conjunction with the 3rd Symposium on PQQ and Quinoproteins. It was an extraordinary occasion for scientists from all over the world to meet and discuss new developments in these overlapping fields. Several sessions were dedicated to the molecular aspects of Vitamin B6 and Quinone dependent enzymes, as well as to the cellular, biomedical and nutritional aspects. The congress was inaugurated by Paolo Fasella in his capacity as General Director of Science, Research and Development of the Commission of the European Communities, with an overview on Intemational Scientific Collaboration. The scientific sessions started with a talk on the History of Vitamin B6 given by David Metzler who at the very last minute presented Esmond Snell's paper adding some personal remarks. Unfortunately, both Esmond Snell and Alton Meister had to unexpectedly cancel the trip to Capri. These proceedings contain the papers presented as oral contributions and a few selected poster presentations. The limited number of pages meant we could not publish many interesting poster presentations, including those selected for the three lively and exciting evening poster discussion sessions called by the organizers "Vino, taralli and ... discussion".

Despite the amazing progress made by the stereotactic technique, particularly regarding the localization of the target, despite the extreme caution, which stereotactic neurosurgeons apply at every step of the procedures, despite the routine roentgenologic and physiologic controls (depth EEG, electric stimulation) preceding the production of a lesion, there remains a certain degree of uncertainty regarding the position, shape and extent of the lesion as well as of the electrode track and also regarding unintended lesions in the vicinity. The final answer to these questions depends on the anatomical control. Thus we must be grateful to the authors, who performed 3700 subcortical stereotactic interventions, that they present a careful comparison of the clinical and of the pathologic anatomic findings, in the cases whose brains could be studied. They demonstrate what degree of exactness can be expected from the stereotactic technique. They also present a careful outline of the morphology, physiology, biochemistry and pathology of the structures that are affected in Parkinson patients. In addition this monograph permits one to familiarize oneself with the methods of stimulation and destruction practiced by the authors. The relevant literature is conscientiously quoted. A study of this mono graph will benefit not only the stereotactic neurosurgeon, but also neurophysiologists, pathologists and practicing neurologists.

During the past three decades, histology has seen enormous progress, thanks to new techniques and new investigation instruments. Numerous discoveries of important structures and morphofunctional phenomena have been described in a wealth of papers of ever increasing size and complexity. These publi cations have become difficult to follow, not only because of their number, but also because of a disparity of terminology and the multitude of synonyms employed by different authors. All of this makes reading and comprehension of the progress that has been achieved laborious, even for histologists, but especially for students, researchers in other basic branches of medicine, or clinicians who have to consult histological texts during their studies or investigations. In order to facilitate the orientation of all those interested in histology, a concise and practical volume in encyclopedic style, defining and, at the same time, illustrating fundamental histolog ical terms, enumerating synonyms, and describing morpho functional phenomena has become necessary, both because a work of this genre does not exist and because the list of Latin terms elaborated by the International Anatomical Nomenclature Committee in 1977 does not give illustrations or definitions of histological terms. The present work attempts to redress this deficiency."

As an addition to the European postgraduate training system for young neurosurgeons we began to publish in 1974 this series of Advances and Technical Standards in Neurosurgery which was later sponsored by the European Association of Neurosurgical Societies. This series was first discussed in 1972 at a combined meeting of the Italian and German Neurosurgical Societies in Taormina, the founding fathers of the series being Jean Brihaye, Bernard Pertuiset, Fritz Loew and Hugo Krayenbiihl. Thus were established the principles of European co operation which have been born from the European spirit, flourished in the European Association, and have throughout been associated with this series. 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 we 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.

Systematic screening for congenital hypothyroidism in the newborn was introduced some 15 years ago. The main objective was the prevention of mental retardation due to thyroid hormone deficiency during the early months of life. During the past decade screening programs have become routine throughout most of the industrialized world and many questions relating to implementation, organization and quality control of such programs have been largely resolved. Preliminary IQ and neurological data have indicated that screening and early treatment do, in fact, prevent mental retardation. However, a number of scientific questions related to congenital hypothyroidism remain unanswered and extensive research activities are ongoing in the field. The objective of the organizers of the Brussels workshop was to focus almost exclusively on these current research aspects of the screening programs. This workshop is the third international conference specifically devoted to neonatal thyroid screening. The first was held in La Malbaie in Quebec in the fall of 1979. That meeting was well organized and highly productive. Its proceedings constitute a bible in the field. After the Quebec meeting, we witnessed major and rapid advances in our understanding of neonatal thyroid physiology as well as screening methodology, organiza tion, data management, the significance of an approach to false negative and false positive results,patient follow-up, and assessment of follow-up and treatment, and the psychoneurological evaluation of affected infants. Some of these aspects were further developed during a second highly pro ductive international conference organized in Tokyo in 1982.