and User's Guide Abdominal ultrasound examinations are now performed mainly with real-time instrumentation, thereby giving the user tremendous flexi bility in the manner in which the examination is conducted. However, with such flexibility come significant problems as well. Because fields of view are small, and because the operator can readily move the probe anywhere in the abdomen to see structures in a variety of planes and sections, it is relatively easy to become disoriented or to miss significant findings unless the examination protocol is care fully devised. The operator must approach the task of scanning the patient in a logical and organized way that is related to the patient's clinical findings as well as to the findings discovered during the ultra sound examination. This book has been written to assist the operator in performing an organized and directed ultrasound examination by providing in outline form a sequential approach to the scanning' of abdominal organs and regions. This approach has several functions: 1) to indicate the structures within the organ or region that should be scanned; 2) to suggest other regions to examine if abnormalities within the initially imaged structures are detected; and 3) to suggest differential diagnostic possibilities when abnormalities are seen.