This book is based upon a previous work published in 1983 (Radiology of the Ear). Since that date. the most important advance in the imaging of the petromastoid has been the application of magnetic resonance scanning. especially when combined with the use of the recently introduced paramagnetic contrast agent. Gadolinium DTP A. Although computerised tom- ography remains the dominant investigation in this field. magnetic resonance is becoming increasingly important. The account which follows is an attempt to summarise present knowledge in this division of otorhinolaryngology imaging. The format of the chapters has been retained from the original work. with an initial account of imaging techniques and normal anatomy followed by chapters on congenital ear disease. trauma. inflammatory disease and neoplasia. Acoustic neuroma is given a separate section and there are two final chapters on vertigo and otosclerosis. The authors are deeply indebted to their surgical colleagues for cooperation and help in the preparation of the text and their readiness to allow access to clinical material. In this respect. we are particularly indebted to Professor Ronald Hinchcliffe. who has written the Foreword. We are greatly indebted to Dr. Hermann Wilbrand ofUppsala. Sweden. for some line drawings and to Drs. Anthony Lloyd and David Beale. Consultant Neuroradiologists at the Walsgrave Hospital. Coventry. for several radiographs. including many of the angiograms and MR scans.