Radiologists continue to dominate the noncardiac point-of-care ultrasound market. However, radiologists’ share of exams has dipped slightly and the widespread diffusion of point-of-care systems may be problematic, according to a study published in the November issue of the Journal of the American College of Radiology.

In recent years, researchers and professional organizations have advocated for the adoption of point-of-care ultrasound by nonradiologist physicians and predicted the advent of the “ultrasound stethoscope.” Consequently, David C. Levin, MD, of the department of radiology at Thomas Jefferson University Hospital in Philadelphia, and colleagues sought to determine utilization rates by radiologists and other physicians.

The researchers mined Medicare Part B databases for 2004 to 2009 and calculated utilization rates of noncardiac ultrasound per 1,000 beneficiaries by provider specialty. They also compared changes in utilization over the course of the study.

From 2004 to 2009, the overall utilization of noncardiac point-of-care ultrasound jumped 21 percent, with radiologists performing the majority of exams. However, while radiologists saw 17 percent growth over the five-year study, nonradiologists experienced 28 percent growth.

During the study period, radiologists’ market share eroded from 56.6 percent in 2004 to 54.9 percent in 2009.

Levin et al referred to a 2006 study published in JACR that expressed pessimism about the future role of ultrasound in radiology. “However, our data suggest that the outlook for ultrasound continuing to be performed by radiologists is considerably more favorable than Cronan had foreseen five years ago. Nevertheless, his concerns remain legitimate today.”

One of the primary causes of concern, according to Levin and colleagues, is the discrepancy between nonradiologists’ approach to ultrasound education and training and the American College of Radiology (ACR) standards.

While nonradiologist experts and the American Medical Association tout the relative ease of use and minimal training requirements for point-of-care ultrasound, studies conducted by radiologists have demonstrated that it takes considerable training and experience to achieve competency. In fact, ACR training standards require nonradiologist users to interpret 500 cases under supervision in each anatomic area pertaining to his or her practice.

The authors outlined four additional concerns:

• The cost of equipping every medical student and physician with a point-of-care system;
• The potential onslaught of millions of self-referred claims for ultrasound studies;
• The lack of evidence that such scans improve outcomes or prognosis, shorten length of stay or lead to financial savings; and
• Increased diffusion of point-of-care ultrasound would lead to an increase in incidental or equivocal findings that require follow-up.

The study did not account for informal, nonbilled ultrasound studies, which seem to be performed fairly often by nonradiologists, noted Levin et al. Another limitation of the study is that obstetrical use is under-represented among Medicare beneficiaries.

The authors concluded, “The role of radiologists in noncardiac ultrasound remains quite strong. Progressive miniaturization of ultrasound equipment may change that, and these utilization trends will require further watching and additional research in coming years.”