Ultrasound added to Imaging Department

“It’s a girl!”

But today, that exclamation might not happen in the delivery room. It might happen weeks before.

How? Through ultrasound imaging; the use of high frequency sound wave to see inside the body.

It’s an imaging technique that has some advantages over other types of diagnostic radiology such as X-ray or CT scans; there is no ionizing radiation, it’s a quick and usually painless way to take a look at certain parts of the body, and it’s a real time look at what is happening.

Ultrasound waves don’t pass through bone or air well, so open spaces like stomachs or bowels don’t provide good images. Ultrasound waves do reflect off of boundaries of soft tissue, however, so ultrasound exams are used on organs like the liver, kidney, spleen, pancreas or gallbladder and other soft tissue areas like the breast or thyroid.

Thanks to the Doppler effect, or the change in sound frequency as something moves away or toward the listener (a train is a good example), ultrasound can look at areas with movement. Blood flows through an artery can be seen, for instance, as well as the condition of the artery itself.

And of course, because there is no ionizing radiation, a prenatal baby’s condition can be checked ... and the parents told whether they can expect a boy or girl.

Last August Bigfork Valley welcomed Ultrasound Tech Libby Nelson to its imaging staff. Libby came to Bigfork Valley from St. Mary’s, where she had worked for the year following her graduation from St. Cloud Technical College with an associate’s degree in diagnostic and medical sonography.

Originally graduating from Grand Rapids High School, Libby received her associate’s degree in general studies from Itasca Community College before going to the University of North Dakota with a goal in aviation. When that did not work out as she had anticipated, she sought another career and became interested in the potential of ultrasound.

It wouldn’t be easy. First she had to complete prerequisites at Hibbing Community College in anatomy, physiology and physics. She did, was accepted, and finished her college at St. Cloud Tech.

It has proven to be a fascinating career for her. “I love it,” she said. “I’m still amazed at the whole thing.”

During an exam which may last from 15 minutes to 45 minutes, Libby will first apply a gel to the skin over the area to be scanned. The gel eliminates air and provides a good contact between the probe and the skin. The probe, or transducer, then sends millions of pulses each second of high frequency sound – too high for the ear to hear – and receives back reflected sound waves. Using the speed of sound in tissue, the computer can calculate and display the surface the sound was reflected from.

The sonogram is displayed in real time on the computer monitor, and Libby can make a variety of adjustments in the display and the quality of the sound waves to get the best image for the radiologist.

In women’s health, ultrasound has been particularly important. It’s the next most non-invasive step to take when a mammogram shows an abnormality, pointed out Mammography Technician Mary Christensen. And, because it can be used while the procedure is going on, it can be used to guide needle biopsies to remove a small sample of breast tissue for lab testing without surgery.

That’s also true for biopsies to check other organs like the liver. Ultrasound is able to see muscles, tendons, nerves and even blood, and see them to a very fine detail, pointed out radiologist Dr. Paul Olson. He uses ultrasound images when he is putting a needle in or next to small structures like veins or tendons.

In fact, he said, he has used it to find and destroy a bundle of damaged nerves that was less than about 1/8 inch and to use a needle the size of a thread to peel scar tissue off a nerve, both procedures alleviating chronic pain for his patients.

This machine is one of the best on the market, he said, because it offers such high detail for the physician to work with.