A sixteen-year-old softball pitcher felt a painful click in her elbow every time she threw the ball. Her doctors were perplexed: X-rays and MRI scans showed nothing amiss. But using a real-time ultrasound of her elbow as her arm went through the pitching motion, doctors discovered the cause of the troublesome click: the head of the radius partly slipped out of joint.

"We were able to tell in real-time that this is the patient's problem," said Dr. Levon Nazarian, a radiologist at Thomas Jefferson University in Philadelphia. If doctors had first referred her for a sonogram when she came in with the complaint "it would have saved a lot of money and time and pain for her," he said.

Nazarian told this story during his talk at the Ultrasound First Forum, held Monday at the New York Marriott Marquis in Times Square. Organized by the American Institute of Ultrasound in Medicine, the event aimed to compel providers to consider ultrasound before other more expensive, and potentially less safe, types of imaging, for a range of clinically indicated conditions — including in sports medicine.

"Just about every structure that's likely to be injured in an athlete, we have some way of assessing it with ultrasound imaging," Nazarian said.

Fast, cheap, accurate?

According to Nazarian and many other attendees, ultrasound has several advantages. It's portable, which means it can be brought fieldside for an in-game scan, it can be used in real time to find the source of the pain, and it's much cheaper than the main competing modality, MRI.

For at least some conditions, it goes toe-to-toe with MRI for accuracy, such as rotator cuff tears, Nazarian said. In a meta-analysis published in the June 2009 issue of the American Journal of Roentgenology, Nazarian and his colleagues found MR and ultrasound both had around 85 percent sensitivity and between 90 and 92 percent specificity for finding the shoulder injury. (MR arthrography, however, which involves the injection of a contrast agent, had the highest sensitivity and specificity; the article recommended ultrasound, or MRI, as a frontline tool and MR arthography for ambiguous findings.)

Still, ultrasound is, in general, used less often. "Usually we like to do the less expensive test first, but in musculoskeletal we definitely do the most expensive test first and we do the less expensive test if indicated," Nazarian said.

Ultrasound goes to the Olympics

But it's making some inroads in elite sports medicine. Bill Moreau, managing director of sports medicine for the U.S. Olympic Committee, said a recent in-house analysis revealed USOC used 500 percent more ultrasound than MRI at its headquarters in Colorado Springs. He said they performed in a recent training season 284 ultrasounds, 308 X-rays and 33 MRI scans.

"We feel it's almost an extension of the physical examination," he said. "It's also extremely cost-effective for us."

He also had a dramatic example of its usefulness. In the run-up to the 2010 Winter Games in Vancouver, a short-track speed skater slipped on the track and stabbed his thigh with his own skate, the sharp, 18-inch blade cleaving through flesh and hitting his femur, leaving a bone bruise. While it seemed a lifetime of training went up in smoke, during a telesongraphy consultation with an expert in Barcelona, Spain, ultrasound scans revealed the blade missed the athlete's tendon. After a surprisingly quick recovery, which was monitored with regular ultrasounds, he went on to win two bronze medals at the Games.

Is it safe?

A big driver for ultrasound is not just that it's relatively less expensive. It's that it might be safer than X-ray-based imaging. The modality uses acoustic energy, not ionizing radiation. But the technology is not inherently risk-free. The two main biological effects of ultrasound are heat and cavitation, or the creation of bubbles which can collapse and injure nearby tissue with shockwaves. Cavitation is what causes pitting in steel propeller blades in ships, according to Frederick Kremkau, an electrical engineer and professor at Wake Forest University School of Medicine.

Speaking to the forum, Kremkau said that in fact, therapeutic ultrasound — now often used in physical therapy to heat up sore limbs — was used before diagnostic ultrasound. And more powerful ultrasound-based systems, called High-Intesity Focused Ultrasound, use precise blasts of acoustic energy to destroy tumors and uterine fibroids.

Still, diagnostic ultrasound uses much lower levels of energy, and the risks are minimal.

"There's no known risk to the use of ultrasound in how we apply it today," Kremkau said.

Dr. Brian S. Garra, a radiologist with the Washington, D.C. VA hospital who also works with the Food and Drug Administration, said diagnostic ultrasound produces 1 watt per square centimeter, less than 1,000th of the power of a HIFU system. Similarly, a lithotripsy device, which uses mechanical energy to break up kidney stones, produces vastly more compressional wave pressure than ultrasound, he said.

Difficulties

But the wider adoption of ultrasound for musculoskeletal or other conditions has to struggle with reimbursement challenges and the nature of ultrasound, which is seen in medicine as more operator-dependent than other modalities. In a morning panel discussion at the conference, one audience member also quipped that ultrasound interpretation was hard even for radiologists.

What will it take to bring payers on board? The medical director of a benefits management organization observed that doctors see great results with ultrasound in academic settings for MSK and other conditions, but payers will want to see this translated to community-level hospitals or clinics. He said insurance plans could be convinced to back ultrasound first, but not if every ultrasound led unfailingly to an MRI because the ultrasound scan was ambiguous or uninterpretable.

One popular suggestion — which drew hearty applause when mentioned by AIUM president Dr. Alfred Abuhamad — was encouraging the accreditation of more facilities in ultrasound, as a marker of quality and to ensure better training.

Of course, economics might carry the day in the end. As the payment system transitions from fee-for-service to accountable care organizations and other models, it will hugely influence what exams get ordered. "If we have only a limited amount of funds that's going to be the primary driver of what's going to happen," said Dr. Bruce Gilbert, the director of ultrasound with the Arthur Smith Institute of Urology at North Shore-LIJ Health System.

In his talk earlier in the morning, Nazarian also stressed the importance of economics.

"I've always said if ultrasound reimbursed three or five times more than MRI, this would be an MRI first forum," he joked.