by Dr. Donald L. King The past decade has seen the ascent of ultrasonography to a preeminent position as a diagnostic imaging modality for obstetrics and gynecology. It can be stated without qualification that modern obstetrics and gynecology cannot be practiced without the use of diagnostic ultrasound, and in particular, the use of ultrasonogra phy. Ultrasonography quickly and safely provides detailed, high resolution images of the pelvic organs and gravid uterus. The quality and quantity of diagnostic information obtained by ultra sonography far exceeds anything previously available and has had a revolutionary impact on the management of patients. High resolution static images permit the intrauterine diagnosis of fetal growth retardation and fetal abnormalities. In addition to tradi tional images, newer dynamic imaging techniques allow observa tion of fetal motion, cardiac pulsation, and respiratory efforts. The use of ultrasonography for guidance has greatly augmented the safety and utility of amniocentesis. One of the great virtues of diagnostic ultrasound has been its apparent safety. At present energy levels, diagnostic ultrasound appears to be without any injurious effect. Although all the availa ble evidence suggests that it is a very safe modality and that the benefit to risk ratio is very high, the actual safety margin for its use Vll as yet remains unknown. As a consequence, practitioners are urged to limit its use only to those situations in which genuine clinical indica tions exist and real benefit to the patient is likely to result."

by Dr. Nathaniel R. Bronson, 11 This volume serves a two-fold purpose very nieely. For the ophthalmologist there is a presentation of the teehniques and results of ultrasonie examination of the eye and orbit. For the radiologist or general ultrasonographer the essential oeular anat- omy and pathology are deseribed with these findings. Unlike eon- ventional x-rays or statie general body ultrasonograms, the exami- nation of the eye by real-time ultrasonography must be done by an examiner with extensive personal knowledge of the eye and the orbit, both anatomieally and pathologieally. The student must realize that the Polaroid photographs ean only show an example of what was transiently seen, such as spot films taken during fturo- seopy. This is further eomplieated by the poor reproduetion by Polaroid films of the aetual gray sc ale seen during the examination. Considerable work has been done to prepare this text. The author has done elinieal ultrasonography of many eyes and presents the findings of his experienee. As in most fields of medieal diagnostie work this experienee is essential to aehieve the best results. The beginner in ophthalmie ultrasonography is eneouraged to work with known pathology. Fortunately, pathologie ehanges in the eye vii FOREWORD can frequently be seen with a slit lamp or an compared our ultrasonic diagnosis of orbital ophthalmoscope. For example, a known retinal masses with those of the same patient done on a detachment is an ideal case with which to start. CAT scanner.