Parameters such as membrane transport, metabolism and protein incorporation govern the fate of amino acids in living tissue. Is it possible to use positron tomography to measure some of them, and what is their meaning in normal and pathological situations? These questions have been addressed for a long time and no satisfactory answer has yet been given. This book, which derives from an EEC workshop organized in the frame of the Concerted Action on PET Investigation of Cellular Regeneration and Degeneration', held in Lyon in February 1992, gives the present state of knowledge in this field based on the most recent studies. Contributions from 24 leading European and American scientists are presented and discussed in the following four parts: biochemistry and animal studies; amino acids labelling with positron emittors, quality control and metabolites measurement; kinetic modelling of amino acids transport, metabolism, and protein incorporation; clinical use of amino acids. This book will aid and interest biochemists, radiochemists, pharmacologists, neurologists, oncologists and medical imaging scientists.

This is the fourth volume of Ultrasound in Medicine, the Proceedings of the Annual Scientific Meeting of the American Institute of Ultrasound in Medicine. Unless the Executive Board of the Institute change their mind, it may also be the last. Under these circumstances it is somewhat ironical that some of the deficiencies present in previous volumes appear to have been solved in the present volume. Notably, the Programme Committee, for the first time, exercised a stringent selection procedure by means of which the number of papers selected for presentation was limited with the result that both the quality of papers accepted for presentation and publication was improved and the number of simultaneous sessions at the meeting did not exceed two. The contents of this volume have been divided into the same sections as in previous volumes except that no papers on stan dardization procedures were accepted and a new supplementary section is added consisting of papers given at the Scientific Meeting of the American Society of Ultrasound Technical Specia lists. As in previous editions the readers may consider the engin eering sections at the end of this volume are the most rewarding. Some ingenious new systems are described both in the sections on Doppler techniques and new techniques. Current interest in tissue signatures and characterization are reflected in many of the pap~rs appearing in the Tissue Interactions section.

New Frontiers in Biomedical Engineering will be an edited work taken from the 1st Annual World Congress of Chinese Biomedical Engineers - Taipei, Taiwan 2002. As the economy develops rapidly in China and the Asian-Pacific population merges into the global healthcare system, many researchers in the West are trying to make contact with the Chinese BME scientists. At WCCBME 2002, invited leaders, materials scientists, bioengineers, molecular and cellular biologists, orthopaedic surgeons, and manufacturers from P.R. of China, Taiwan, Singapore and Hong Kong covered all five major BME domains: biomechanics, biomaterials and tissue engineering, medical imaging, biophotonics and instrumentation, and rehabilitation. This edited work taken from the World Congress proceedings will capture worldwide readership.

This book provides a complete overview of all modalities used for hand and wrist imaging, along with a complete over- view of the various disease entities that can be diagnosed. As a state-of-the-art overview of hand and wrist imaging it is a reference work for radiologists, hand surgeons, ortho- pedists, traumatologists, rheumatologists and internists and their residents in training. The chapters are written by ex- perts in musculoskeletal radiology from various European countries and the USA.

The articles collected in this volume are based on lectures given at the IMA Workshop, "Computational Radiology and Imaging: Therapy and Diagnostics", March 17-21, 1997. Introductory articles by the editors have been added. The focus is on inverse problems involving electromagnetic radiation and particle beams, with applications to X-ray tomography, nuclear medicine, near-infrared imaging, microwave imaging, electron microscopy, and radiation therapy planning. Mathematical and computational tools and models which play important roles in this volume include the X-ray transform and other integral transforms, the linear Boltzmann equation and, for near-infrared imaging, its diffusion approximation, iterative methods for large linear and non-linear least-squares problems, iterative methods for linear feasibility problems, and optimization methods. The volume is intended not only for mathematical scientists and engineers working on these and related problems, but also for non-specialists. It contains much introductory expository material, and a large number of references. Many unsolved computational and mathematical problems of substantial practical importance are pointed out.

Medical Image Databases covers the new technologies of biomedical imaging databases and their applications in clinical services, education, and research. Authors were selected because they are doing cutting-edge basic or technology work in relevant areas. This was done to infuse each chapter with ideas from people actively investigating and developing medical image databases rather than simply review the existing literature. The authors have analyzed the literature and have expanded on their own research. They have also addressed several common threads within their generic topics. These include system architecture, standards, information retrieval, data modeling, image visualizations, query languages, telematics, data mining, and decision supports. The new ideas and results reported in this volume suggest new and better ways to develop imaging databases and possibly lead us to the next information infrastructure in biomedicine. Medical Image Databases is suitable as a textbook for a graduate-level course on biomedical imaging or medical image databases, and as a reference for researchers and practitioners in industry.

Endoanal and endorectal ultrasound represents considerable progress in the field of anorectal imaging. Its importance in the staging of rectal and anal cancer, in identifying perianasto- motic neoplastic recurrences, in defining acute and chronic suppurative disease and in assessing sphincteral anatomical integrity, is now a confirmed reality. The evidence provided by endoanal and endorectal ultrasonography guides the colorectal surgeon in his choice among the various therapeutic approaches and helps in assessing the effects of the treatments applied. The great flexibility and high degree of reliability make this exploratory method an indispensable tool at all stages of the clinical course in the majority of patients with anorectal problems, including the fundamental follow-up stage. The publication of this excellent volume on intraanal and intrarectal ultrasonog- raphy is therefore to be appreciated, especially since it is in the form of an atlas. As we are dealing with imaging, it is particularly appropriate that it is the images that tell the story. Like all important things, this volume does not come out of nothing. It is the result of many years of skilled work by Drs. G.A. Santoro and G. Di Falco and is based on the experience of internationally renowned professional experts. The ten sections of the atlas begin with general information on ultrasonography, gradually progressing to the technical problems of the method and the aspects rela- tive to anorectal tumors.This last section leads to a review of traditional and mod- ern therapeutic possibilities.

Imaging of the Dopaminergic system in the human brain with the in vivo use of Positron Emis- sion Tomography has emerged in the late 1980s as a tool of major importance in Clinical Neuros- ciences and Pharmacology. The last few years have witnessed the rapid development of new radiotracers specific to receptors, reuptake sites and enzymes of the dopamine system; the application of these radiotracers has led to major breakthroughs in the pathophysiology and therapy of movement disorders and schizophrenic-like psychoses. This book is the first to collect, in a single volume, state-of-the-art contributions to the various aspects of this research. Its contents address methodological issues related to the design, labelling, quantitative imaging and compartmental modelisation of radioligands of the post-synaptic, pre-synaptic and enzyme sites of the dopamine system and to their use in clinical research in the fields of Parkinson's disease as well as other movement disorders, psychoses and neuroleptic receptor occupancy. The chapters were written by leading European scientists in the field of Positron Emission Tomography, gathered together in Caen (France, November 1990) under the aegis of the EEC Concerted Action on "PET Investigations of Cellular Regeneration and Degeneration. This book provides a current and comprehensive overview on PET studies of the brain dopamine system which should aid and interest neurologists, psychiatrists, pharmacologists and medical imaging scientists. J. C. Baron D. Comar L. Farde J. L. Martinot B. Mazoyer August 1991 ix LIST OF CONTRffiUTORS Dr Yves Agid DrL.

The aim of this Atlas is to present the three-dimensional arrangement of the liver structures, which should be familiar to those who diagnose and treat diseases of the liver, particularly in an era when the methods of diagnostic imaging and surgical treatment are becoming increasingly sophisticated. For this purpose a series of corrosive preparations of the blood vessels and bile ducts of the liver was made and photographed. In addition to the normal situations, many frequent and rare variations are shown. The Atlas also shows some blood vessels that have not been adequately described or are not well-known in the reference literature, but are nevertheless of great importance in performing segmental liver resections.This Atlas takes a fresh approach to the subject. The method used allows the size, three-dimensional arrangement and structure of the blood vessels and bile ducts of the liver to be preserved. The majority of photographs were taken from the direction from which surgeons see the liver during an operation. This, together with the schematic presentations complementing most of the photographs, gives a further instructional value to the work. With colour photographs and explanatory text, the Atlas forms a basic guide to orientation inside the liver parenchyma, to understanding and diagnosing certain pathological processes and to planning surgcial procedures.

Recent years have witnessed dramatic advances in the development and use of magnetic resonance imaging (MRI) techniques that can provide quantitative measures with some degree of pathological specificity for the heterogeneous substrates of multiple sclerosis (MS). Magnetic resonance spectroscopy (MRS) is one of the most promising of these techniques. Thanks to MRS, axonal damage is no longer considered an end-stage phenomenon typical of only the most destructive lesions and the most unfortunate cases, but rather as a major component of the MS pathology of lesions and normal-appearing white matter at all the phases of the disease. This new concept is rapidly changing our understanding of MS pathophysiology and, as a consequence, the therapeutic strategies to modify the disease course favorably. Many of the authors have pionereed the use of MRS in MS, thus contributing to the foundation of the "axonal hypothesis."

'Morphological imaging' and 'functional imaging' are current mainstays for the diagnosis, successful treatment and accurate follow-up of patients with endocrine disorders. Functional and Morphological Imaging of the Endocrine System provides the reader with comprehensive but concise insights in the application of cutting edge imaging techniques and updated imaging protocols for the diagnosis and treatment of hypersecretory hormonal syndromes and functional endocrine masses.

The key contribution of the approach to x-ray mammographic image analysis developed in this monograph is a representation of the non-fatty compressed breast tissue that we show can be derived from a single mammogram. The importance of the representation, called hint, is that it removes all those changes in the image that are due only to the particular imaging conditions (for example, the film speed or exposure time), leaving just the non-fatty interesting' tissue. Normalising images in this way enables them to be enhanced and matched, and regions in them to be classified more reliably, because unnecessary, distracting variations have been eliminated. Part I of the monograph develops a model-based approach to x-ray mammography, Part II shows how it can be put to work successfully on a range of clinically-important tasks, while Part III develops a model and exploits it for contrast-enhanced MRI mammography. The final chapter points the way forward in a number of promising areas of research. Audience: This book has been written for a wide readership, including medical image analysts, medical physicists, radiologists, breast surgeons, and research students. The mathematics and algorithms have been relegated to boxes so that the book can be read and understood even if the mathematical detail is skipped. Large parts of the monograph will be of interest to clinicians generally and to patients.

Mathematical morphology (MM) is a theory for the analysis of spatial structures. It is called morphology since it aims at analysing the shape and form of objects, and it is mathematical in the sense that the analysis is based on set theory, topology, lattice algebra, random functions, etc. MM is not only a theory, but also a powerful image analysis technique. The purpose of the present book is to provide the image analysis community with a snapshot of current theoretical and applied developments of MM. The book consists of forty-five contributions classified by subject. It demonstrates a wide range of topics suited to the morphological approach.

Since the introduction of myocardial perfusion imaging and radionuclide angiography in the mid-seventies, cardiovascular nuclear medicine has undergone an explosive growth. The use of nuclear cardiology techniques has become one of the cornerstones of the noninvasive assessment of coronary artery disease. In the past 15 years major steps have been made from visual analysis to quantitative analysis, from planar imaging to tomographic imaging, from detection of disease to prognosis, and from separate evaluations of perfusion, metabolism, and function to an integrated assessment of myocardial viability. In recent years many more advances have been made in cardiovascular nuclear imaging, such as the development of new imaging agents, reevaluation of existing procedures, and new clinical applications. This book describes the most recent developments in nuclear cardiology and also addresses new contrast agents in MRI. What's New in Cardiac Imaging will assist the clinical cardiologist, the cardiology fellow, the nuclear medicine physician, and the radiologist in understanding the most recent achievements in clinical cardiovascular nuclear imaging.

This volume contains the proceedings of the First International Conference on Eicosanoids and Other Bioactive Lipids in Cancer and Radiation Injury held in Detroit, Michigan on October 11-14, 1989. The program consisted of 83 oral and 29 poster presentations, 74 of which are included in these proceedings. The major sponsors of the conference were the Armed Forces Radiobiology Research Institute, located in Bethesda, Maryland, the Radiation Oncology Research and Development Center of the Gershenson Radiation Oncology Center, Harper Hospital in Detroit, Michigan, and Schering AG of West Germany. Eighteen other organizations provided additional support. The conference was unique in its attempt to link the eicosanoid and lipid researchers in the radiobiology and cancer disciplines. The diverse roles that eicosanoids and other bioactive lipids play in these biological phenomena including the participation of lipid oxidation in conversion of procarcinogens, positive and negative modulation of tumor growth, immunomodulation, tissue injury, and yet protection and enhancement of cancer therapy, necessitated scientific interaction to sort out and understand these complex and sometimes contradictory observations. The success of this effort is reflected not only through these proceedings, but also through the decision to continue the conference series with a second meeting to be held in Berlin between September 17-21, 1991.

Magnetic resonance imaging became clinical in 1981 and since that time, has spread in the United States, Europe and Japan like wild fire. The tremendous advantages of the method consisting of safety, superb soft tissue contrast resolution, the ability to study flow, the ability to image in any plane or acquire data in 3D and an almost infinite array of sequences capable of distinguishing between disease and normal tissue, normal and abnormal blood flow make it incomparable for the diagnosis and study of multiple diseases and is particularly valuable in studying the heart and major vessels. The authors of this book have understood that the secret of success of MR imaging in the study of the heart is to combine the knowledge of anatomy of the heart, the coronary vessels, the pericardium and large vessels with the intricacies of MR imaging. This is why they go deeply into the basic principles of NMR, starting from the essentials and going then into detailed techniques of acquiring images from traditional spin echo to gradient echo and ultra fast imaging approaches, such as the multi shot and EPI. The flow phenomena are also discussed in detail from flow and magnetic field gradients diastolic pseudogating.

Physics-Based Deformable Models presents a systematic physics-based framework for modeling rigid, articulated, and deformable objects, their interactions with the physical world, and the estimate of their shape and motion from visual data. This book presents a large variety of methods and associated experiments in computer vision, graphics and medical imaging that help the reader better to understand the presented material. In addition, special emphasis has been given to the development of techniques with interactive or close to real-time performance. Physics-Based Deformable Models is suitable as a secondary text for graduate level courses in Computer Graphics, Computational Physics, Computer Vision, Medical Imaging, and Biomedical Engineering. In addition, this book is appropriate as a reference for researchers and practitioners in the above-mentioned fields.

Neurosurgery o/the Future: Computers and Robots in Clinical Neurosurgical Practice and in Training - a Philosophical Journey into the Future Many present day neurosurgeons believe that they already obtain good results in operative surgery with the benefit of the operating microscope and other aids which have become available in the last three decades and that the introduction of computers and robots to the operating theatre is superfluous. However, it is clear from analogy with the function of the airline pilot, another profession where there are great demands on manual skill and on spatial awareness, that these devices do have much to offer neurosurgery. Classical neurosurgery, in the time of Cushing, Dandy and Scarff, was based on a three dimensional picture of the patient's brain formed in the surgeon's mind and often illustrated in elegant drawings. Such pictures were based on neuroradiological studies by pneumoencephalography, ventriculography or by angiography. Generally these stud ies showed the presence and position of a lesion by displacement of normal brain structures and the picture was built up by interference. This was then converted by the experienced neurosurgeon into a plan for the craniotomy site and the trajectory of the surgical approach. Once the brain was exposed further pre-operative information was obtained by visual inspection and by palpation with the brain needle. These classical forms ofneuroradiology have largely been superseded by computerised tomography and by magnetic resonance imaging."

The clinical use of nuclear cardiology for the assessment of myocardial ischemia continues to grow at an unprecedented rate. Part of the reason for this growth is the technical advances in single photon emission computerized tomography (SPECT). SPECT has been shown to provide high contrast images superior to planar imaging techniques. An important and recent technical advancement in SPECT has been ECG-gated myocardial perfusion SPECT to generate simultaneous myocardial perfusion and function information from a single study. Automated, quantitative techniques have facilitated the widespread application of this breakthrough. Another recent advancement has been the use of attenuation correction techniques to help remove the effects of the physical phenomena that degrades the visual and quantitative accuracy of SPECT images. Another reason for the growth of the clinical use of nuclear cardiology is the large body of published evidence documenting the effectiveness of SPECT techniques for assessing myocardial ischemia, myocardium at risk, viable myocardium and stunned or hibernating myocardium. These assessments have been shown to be important not only in diagnosis but also in prognosis. This book is divided into three major sections, each addressing the important topics of nuclear cardiology. The first section is a that have led to the clinical success description of the technical aspects of state-of-the-art myocardial perfusion SPECT imaging. This section deals with the radionuclides, instrumentation, image acquisition and analysis, interpretation and quantification techniques used in the most progressive nuclear cardiology clinics.

Goals of the Book Overthelast thirty yearsthere has been arevolutionindiagnostic radiology as a result oftheemergenceofcomputerized tomography (CT), which is the process of obtaining the density distribution within the human body from multiple x-ray projections. Since an enormous variety of possible density values may occur in the body, a large number of projections are necessary to ensure the accurate reconstruction oftheir distribution. There are other situations in which we desire to reconstruct an object from its projections, but in which we know that the object to be recon structed has only a small number of possible values. For example, a large fraction of objects scanned in industrial CT (for the purpose of nonde structive testing or reverse engineering) are made of a single material and so the ideal reconstruction should contain only two values: zero for air and the value associated with the material composing the object. Similar as sumptions may even be made for some specific medical applications; for example, in angiography ofthe heart chambers the value is either zero (in dicating the absence of dye) or the value associated with the dye in the chamber. Another example arises in the electron microscopy of biological macromolecules, where we may assume that the object to be reconstructed is composed of ice, protein, and RNA. One can also apply electron mi croscopy to determine the presenceor absence ofatoms in crystallinestruc tures, which is again a two-valued situation."

Itgivesmegreatpleasuretoeditthisbook. Thegenesisofthisbookgoes backtotheconferenceheldattheUniversityofBolognainJune1999,on collaborativeworkbetweentheUniversityofCaliforniaatBerkeleyandthe UniversityofBologna. Theoriginalideawastoinvitesomespeakersatthe conferencetosubmitarticlestothebook. Thescopeofthebookwaslater- hancedand,inthepresentform,itisacompilationofsomeoftherecentwork usinggeometricpartialdi?erentialequationsandthelevelsetmethodology inmedicalandbiomedicalimageanalysis. Thesynopsisofthebookisasfollows:Inthe?rstchapter,R. Malladi andJ. A. Sethianpointtotheoriginsoftheuseoflevelsetmethodsand geometricPDEsforsegmentation,andpresentfastmethodsforshapes- mentationinbothmedicalandbiomedicalimageapplications. InChapter 2,C. OrtizdeSolorzano,R. Malladi,andS. J. Lockettdescribeabodyof workthatwasdoneoverthepastcoupleofyearsattheLawrenceBerkeley NationalLaboratoryonapplicationsoflevelsetmethodsinthestudyand understandingofconfocalmicroscopeimagery. TheworkinChapter3byA. Sarti,C. Lamberti,andR. Malladiaddressestheproblemofunderstanding di?culttimevaryingechocardiographicimagery. Thisworkpresentsvarious levelsetmodelsthataredesignedto?tavarietyofimagingsituations,i. e. timevarying2D,3D,andtimevarying3D. InChapter4,L. VeseandT. F. Chanpresentasegmentationmodelwithoutedgesandalsoshowextensions totheMumford-Shahmodel. Thismodelisparticularlypowerfulincertain applicationswhencomparisonsbetweennormalandabnormalsubjectsis- quired. Next,inChapter5,A. EladandR. Kimmelusethefastmarching methodontriangulateddomaintobuildatechniquetounfoldthecortexand mapitontoasphere. Thistechniqueismotivatedinpartbynewadvances infMRIbasedneuroimaging. InChapter6,T. DeschampsandL. D. Cohen presentaminimalpathbasedmethodofgroupingconnectedcomponentsand showcleverapplicationsinvesseldetectionin3Dmedicaldata. Finally,in Chapter7,A. Sarti,K. Mikula,F. Sgallari,andC. Lamberti,describean- linearmodelfor?lteringtimevarying3Dmedicaldataandshowimpressive resultsinbothultrasoundandechoimages. IoweadebtofgratitudetoClaudioLambertiandAlessandroSartifor invitingmetoBologna,andlogisticalsupportfortheconference. Ithank thecontributingauthorsfortheirenthusiasmand?exibility,theSpringer mathematicseditorMartinPetersforhisoptimismandpatience,andJ. A. Sethianforhisunfailingsupport,goodhumor,andguidancethroughthe years. Berkeley,California R. Malladi October,2001 Contents 1 FastMethodsforShapeExtractioninMedicaland BiomedicalImaging...1 R. Malladi,J. A. Sethian 1. 1Introduction...1 1. 2TheFastMarchingMethod...3 1. 3ShapeRecoveryfromMedicalImages...6 1. 4Results...10 References...13 2 AGeometricModelforImageAnalysisinCytology...19 C. OrtizdeSolorzano,R. Malladi,,S. J. Lockett 2. 1Introduction...19 2. 2GeometricModelforImageAnalysis...20 2. 3SegmentationofNuclei...22 2. 4SegmentationofNucleiandCellsUsingMembrane-RelatedProtein Markers...31 2. 5Conclusions...37 References...38 3 LevelSetModelsforAnalysisof2Dand3D EchocardiographicData...43 A. Sarti,C. Lamberti,R. Malladi 3. 1Introduction...43 3. 2TheGeometricEvolutionEquation...45 3. 3TheShock-TypeFiltering...46 3. 4ShapeExtraction...49 3. 52DEchocardiography...52 3. 62D+timeEchocardiography...53 3. 73DEchocardiography...56 3. 83D+timeEchocardiography...58 3. 9Conclusions...59 References...61 4 ActiveContourandSegmentationModelsusing GeometricPDE'sforMedicalImaging...63 T. F. Chan,L. A. Vese 4. 1Introduction...63 4. 2DescriptionoftheModels...64 4. 3ApplicationstoBio-MedicalImages...68 4. 4ConcludingRemarks...68 References...7 0 VIII Contents 5 SphericalFlatteningoftheCortexSurface...77 A. Elad(Elbaz),R. Kimmel 5. 1Introduction...77 5. 2FastMarchingMethodonTriangulatedDomains...80 5. 3Multi-DimensionalScaling...80 5. 4CortexUnfolding...84 5. 5Conclusions...86 References...86 6 GroupingConnectedComponentsusingMinimalPath Techniques...91 T. Deschamps,L. D. Cohen 6. 1Introduction...91 6. 2MinimalPathsin2Dand3D...93 6. 3FindingContoursfromaSetofConnectedComponentsR...96 k 6. 4FindingaSetofPathsina3DImage...102 6. 5Conclusion...103 References...104 7 NonlinearMultiscaleAnalysisModelsforFilteringof 3D+TimeBiomedicalImages...107 A. Sarti,K. Mikula,F. Sgallari,C.

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 scientificconferences 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 scientificpapers 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 fieldsand constitute the first part of each volume."

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.

As Lord Kelvin said, "Fourier's theorem is not only one of the most beautiful results of modern analysis, but it may be said to furnish an indispensable instrument in the treatment of nearly every recondite question in modern physics." This has remained durable knowledge for a century, and has extended its applicability to topics as diverse as medical imaging (CT scanning), the presentation of images on screens and their digital transmission, remote sensing, geophysical exploration, and many branches of engineering. Fourier Analysis and Imaging is based on years of teaching a course on the Fourier Transform at the senior or early graduate level, as well as on Prof. Bracewell's 1995 text Two-Dimensional Imaging. It is an excellent textbook and will also be a welcome addition to the reference library of those many professionals whose daily activities involve Fourier analysis in its many guises.

The small neck of the aneurysm afforded an easy surgical attack. An ordinary flat silver clip was placed over the sac and tightly compressed obliterated it completely. The clip was flush with the wall of the carotid artery. The sac, lateral to the silver clip, was then picked up with the forceps and thrombosed by the electocautery. Walter Dandy reporting his successful operation of a posterior communicating aneurysm on March 23, 1937. Walter Dandy's patient left the hospital in good health 2 weeks later, and from his report one may gain the impression that the operation was an easy task. Despite continuous developments during the following decades, it was not until the introduction of the operating microscope and microsurgical techniques that surgical treatment was generally accepted. During the microsurgical era surgical results have continued to improve due to diagnostical, neuroanaesthesi ological, and microsurgical refinements, and improved neurointensive care. Endovascular obliteration has become an important treatment alternative but this has not been included in this particular volume. The purpose of the present supplement of the ACTA NEUROCHIRURGICA is to review some of the elements in the neurosurgical management of patients with aneurysmal subarachnoid haemorrhage that are important for a successful outcome. Professor Helge Nornes has been a major force in the development of new techniques and research strategies in this area for a number of years and has recently retired from the National Hospital in Oslo."