My ultrasound used to look like what?

Imagine walking into your doctor's office for your diagnostic ultrasound for ovarian screening, rounding the corner to the procedure room, and then taking off your clothes and submerging yourself up to your neck in a horse trough full of water. That's how some of the earliest doctors across the world envisioned using ultrasound to image the human body between the 1940s and 1960s. Ultrasound technology was first used by the U.S. military to determine tiny cracks in the hulls of metal ships, not to see into living human bodies. So in 1949 when British doctor John J. Wild had the idea that ultrasound could be used to detect small human tissue irregularities such as cancer, his first goal was simple: how do we get out of the trough?

While some scientists in the 1950s and 1960s were working on ultrasound in pregnancy, John Wild had a different goal: detecting cancer early. Wild spent most of the 1950s designing instruments small enough to screen common cancer sites, convinced that ultrasound could reveal the tiniest abnormalities in human tissue. It turns out, he was right, and we can thank him and his contemporaries for the wide use of ultrasound today.

But before ultrasound technology took off in medicine, scientists who suspected that ultrasound could help them "see" inside a patient had to rely on old military equipment like radar baths and discarded navy radar transducers. Once they proved that imaging human tissue was possible using these machines, they set off to make their own instruments specific to the world of medicine. Ultrasound machines have changed dramatically since then but every machine still needs one thing: a transducer. The transducer creates the sound waves that are sent into the body and then it receives the echoes sent back. These echoes are received by the machine and translated into the tiny blips of light we see on the screen. So where did the horse trough come in? Sound waves move through water faster than through air and are not dispersed as much. (Today we use a water-based gel—fewer spills that way!)

John Wild had the idea to combine the transducer and water together in a handheld device to both remove the patient from a neck-deep bath and better direct the sound waves to a specific location on the body. The result? The Transducer-In-A-Can. Wild's colleagues were worried that the concentration of sound waves and direct contact with the skin would harm a patient. Wild dispelled the myth by testing it on his own arm.

The aptly named Transducer-In-A-Can was just the beginning for ultrasound technology, but we can thank Wild and other early ultrasound scientists for bringing us out of the horse trough and into the world of portable, handheld ultrasound devices. It took until the 1970s for ultrasound, most known for giving expecting parents the first glimpse of their newest family member, to become a regular part of a patient's procedures. It took decades of using discarded equipment, innovation, and creativity to figure out how to turn sound into images, without the free bath.

Lauren Rever completed a curatorial internship in the Division of Medicine and Science, working under curator Judy Chelnick