Friday, 8 July 2016

HISTORY OF ULTRASONIC:   prior to world war 2, sonar,the technique of sending sound waves through water and observing the returning to characterize submerged objects,inspired early ultrasound investigators to explor ways to apply the conceptto medical in 1920 and 1935,sokolov studied the use of ultrasonic waves in detecting metal object mulhausar,in 1931,obtained a patent for using ultrasonic waves,using two transducers to detect flaws in solid.Firestone(1940) and simons (1945) developed pulsed ultrasonic testing using a pulse-echo technique.                
                shortly after the close of world war 2,researchers in japan began to explor the medical diagnostic capabilities of ultrasound.The first ultrasonic instruments used an A-mode presentation with blips on oscilloscope screen. that was followed by a B-mode presentatoin with a two dimensional,gray scale image.
                japans work ultrasound was relatively unknown in the united states and Euroup until the 1950s.Researchers then presented their finding on the use of ultrasound to detect gallstone,breast masses,and tumors to the international medical community.japan was also the firsr country to apply Doppler ultrasound,an application of ultrasound that detects internal moving objects such as blood coursing through the heart for cardiovascular investigation.