ULTRASONIC OPPORTUNITIES 1992 FRY,WILLIAM,J. MEMORIAL LECTURE

William Fry was active in medical ultrasonics a quarter of a century a go. The technology for which Fry was responsible-high frequency focuse d ultrasound for the accurate placement of small lesions within the br ain-opened up new opportunities for his neurosurgical contemporaries. In the following 25 years, the emphasis first shifted to diagnosis and the technology progressed through static bistable scanning, M-mode ec hocardiography, gray-scale and real-time Doppler techniques, and color flow imaging. Ultrasound again has important interventional applicati ons, not only in surgery but also now in imaging. There are opportunit ies for developments in therapy and surgery, tissue characterization, resolution improvement, blood flow measurements, contrast agents, thre e-dimensional scanning, and image display.