17w Dandy Walker Syndrome

17w Dandy Walker Syndrome

Anthony J. Raimondi Kiyoshi Sato Takeyoshi Shimoji The JJrnidy-W«lλ er Sωίdrοme 13 figures and 6 tables, 1984 KARGER S. Karger Basel München Paris London New York Tokyo Sydney

AnthonyJ.Raimondi, MD Division of Neurosurgery, Northwestern University Medical School, Chicago, Illinois, USA Kiyoshi Sato, MD Department of Neurosurgery, Juntendo University, Tokyo, Japan Takeyoshi Shimoji, MD Department of Neurosurgery, Juntendo University, Tokyo, Japan National Library of Medicine, Cataloging in Publication Raimondi, Anthony J., 1928- The Dandy-Walker Syndrome / Anthony J. Raimondi, Kiyoshi Sato, Takeyoshi Shimoji. - Basel; New York: Karger, 1984. 1. Hydrocephalus I. Sato, Kiyoshi II. Shimoji, Takeyoshi WL 350 R153d ISBN 3-8055-1722-X Drug Dosage The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any change in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug. All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher. Copyright 1984 by S. Karger AG, P.O. Box, CH-4009 Basel (Switzerland) Printed in Switzerland by Thíir AG Offsetdruck, Pratteln ISBN 3-8055-1722-X

Contents Preface VII K. Sato, T. Shimoji, A.J. Raimondi I. Review of Literature and Concepts 1 Introduction 1 Definition 2 Various Theories on the Pathomechanism of Dandy-Walker Syndrome 8 Recent Observations on Dandy-Walker Syndrome 11 Summary 15 References 15 A.J. Raimondi, T. Shimoji, K Sato II. Clinical Experience with 37 Patients 21 Introduction 21 Clinical Material 22 Treatment 27 Discussion 40 Conclusion 42 Summary 42 References 43

Contents VI T. Shimoji, K Sato, A.J. Raimondi III. Reliability of Diagnostic Studies in Children with Dandy-Walker Cyst: A Critical Analysis 47 Introduction 47 Clinical Material 48 Results 55 Discussion 65 Summary 72 References 72 Subject Index 77

Preface At the present time it is fashionable to make every effort to avoid eponyms, attempting to emphasize the anatomic and pathologic aspects of a disease entity in establishing nomenclature. One of the unfortunate aspects of eponyms is that the `first' person to describe the entity often does not have his name included in the eponym: Taggart, senior author in the Taggart and Walker 1942 paper, Congenital Atresia of the Foramens of Luschka and Magendie. Another is that at times a significant junior author, Blackfan in the paper Dandy and Blackfan, Internal Hydrocephalus: An Experimental Clinical and Pathological Study, is omitted. Nevertheless, significant contríbutíons are made by people and the clinical entities often are identified with the authors. The Dandy-Walker cyst is just such an instance and, consequently, it is advisable and constructive to adhere to this eponym. In this work an exhaustive review of the literature has been undertaken so as to analyze critically various etiologic, pathogenetic, pathologic, diagnostic, and therapeutic aspects of the very complex developmental, congenital, postinfectious aspects of cystic transformation of the fourth ventricle. Prognosis and natural history are aspects of disease entities that presently attract more attention and assume more importance. Consequently, particular attention has been given to each. In order to treat properly and to analyze the effects of a particular treatment modality or clinical entity, one must be able to diagnose

Preface VIII the disease with precision and to evaluate the eflícacy of the individual treatment modality. Accordingly, much attention, in this book, has been given to analyzing the reliability of diagnostic studies as they apply to initial diagnosis and evaluation of individual treatment modalities: posterior fossa exploration and membrane resection, lateral ventricle shunting, fourth ventricle shunting, combined lateral and fourth ventricle shunting, and so on. Also, the cystic transformation of the fourth ventricle, the relative displacement of the dural sinuses, the development or hypoplasia of vertebral basilar branches, dysgenesis of segments of the corpus callosum, have all been studied and classified. In addition to the exhaustive review of the literature, the authors undertook a detailed study of each of their 37 cases. Age at the time of diagnosis, clinical signs, surgical management, results of surgical management as it pertains to head size and motor function, and intellectual performance have all been collated. An analysis of these results and a final statement concerning the present knowledge of what the overall condition of the child with the Dandy-Walker cyst is, as well as what future information will be needed to understand completely this rather complex clinical entity, are discussed at length. It is hoped that this work may serve as an update on the Dandy-Walker syndrome and, at the same time, stimulate present and future clinicians and investigators to explore experimental animals with this syndrome more fully and to study, more completely, children suffering from this malady.