tic knowledge, a multidisciplinary approach is indis­ Over the past 60 years, radiology has progressively uncovered the human body. At first a fleshless skele­ pensable: clinicians, radiologists, surgeons, radio­ therapists, and pathologists must all contribute their ton for global study, the body then appeared in slices, until with present techniques its smallest respective inputs for every patient referred. More­ over, experience is acquired through knowledge of structures are revealed. The physician at the com­ cases whose diagnosis is certain, and with which new puter console is constantly amazed at the never­ ending series of organ sections and their mUltiple cases can be compared. In this way a data base is created, whether in the physician'S memory or in images arising through manipulation of the signal. Cerebral convolutions, orbital content, bone mar­ that of the computer, which is helpful in making row, the face and all its bones can now be made visi­ diagnoses. ble without any danger to the patient. A lesion can be detected, located and identified; it can be ob­ Dr.

One: Introduction.- Two: Technical Considerations.- 2.0 Summary.- 2.1 The nuclear magnetic resonance (NMR) phenomenon.- 2.2 Relaxation and magnetic relaxation times.- 2.3 Location of magnetic resonance signal.- 2.4 Pulse sequences.- 2.5 Image contrast.- 2.6 Signal-to-noise ratio (S/N), spatial resolution and imaging time.- 2.7 Image acquisition time.- 2.8 MR signal characteristics of soft tissues.- References for Chapter Two.- Three: Case Presentations.- A. Orbital and paraorbital regions.- B. Paranasal sinuses, including nasal cavities.- C. Temporal bone/base of skull.- D. Salivary glands.- E. Nasopharynx.- F Oropharynx and oral cavity.- G. Larynx.- H. Hypopharynx.- I. Parapharyngeal space.- J. Neck.- References for Chapter Three.- Four: Mri Strategy in Evaluating Head and Neck Tumors.- 4.1 Introduction.- 4.2 Optimum MR imaging parameters.- 4.3 MR and head and neck imaging, according to anatomic areas.- 4.4 Gadolinium-DTPA for MR imaging in the head and neck.- 4.5 Unresolved problems.- References for Chapter Four.- Five: Conclusions.