In which decade was the concept of ultrasound first used?

In which decade was the concept of ultrasound first used?

• A. 1920s
• B. 1960s
• C. 1980s
• D. 1940s

Answer: (D)

The concept being tested is the origin of using high-frequency sound to look inside the body. In the 1940s, researchers began exploring whether rapidly oscillating sound waves could travel through tissues and bounce back echoes that reveal internal structures. These early experiments showed that different tissues reflected sound differently, which is the foundational idea behind diagnostic imaging with ultrasound. That groundwork in the 1940s made possible later, more refined diagnostic systems in the 1950s and 1960s, so this decade is when the concept first took practical hold. Earlier work in the 1920s and the more widely recognized clinical developments in the 1950s–60s are related, but the initial concept emerged in the 1940s.

The concept being tested is the origin of using high-frequency sound to look inside the body. In the 1940s, researchers began exploring whether rapidly oscillating sound waves could travel through tissues and bounce back echoes that reveal internal structures. These early experiments showed that different tissues reflected sound differently, which is the foundational idea behind diagnostic imaging with ultrasound. That groundwork in the 1940s made possible later, more refined diagnostic systems in the 1950s and 1960s, so this decade is when the concept first took practical hold. Earlier work in the 1920s and the more widely recognized clinical developments in the 1950s–60s are related, but the initial concept emerged in the 1940s.