Understanding the true nature of a career as a Diagnostic Medical Sonographer in 2017 and beyond means recognizing the uses for ultrasound are rapidly expanding. Now primarily a diagnostic tool, exciting research is giving sonographers a glimpse into the future of ultrasound as a therapeutic or interventional medicine. The National Institute of Biomedical Imaging and Bioengineering (NIBIB) is funding remarkable projects that will lead to the expanded use of ultrasound for healing and not just diagnosing.
Diagnostic versus Therapeutic Ultrasound
Diagnostic Medical Sonographers in the modern health care setting are regularly learning to master the use of high-tech equipment, like the new point-of-care ultrasound equipment. These are exciting technological advances because it means sonographers will have much more flexibility in their ability to deliver services. For example, ultrasound technologists can assist pregnant women in communities that have no medical facility or access to ultrasound equipment.
However, this type of service is still diagnostic ultrasound and not therapeutic or interventional ultrasound. Diagnostic ultrasound refers to the non-invasive imaging of tissues, organs and systems for purposes of monitoring and assessment. Technology has advanced to the point where images can be displayed as 2D, 3D or 3D which shows motion (called 4D). Diagnostic ultrasound is used for:
- Imaging certain internal organs and tissues
- Measuring tissue stiffness (elastography)
- Measuring blood flow through arteries, blood vessels and organs like the heart (Doppler ultrasound)
- Assisting physicians with positioning and guidance of invasive medical instruments, like a needle or catheter
Therapeutic and interventional ultrasound takes the use of ultrasound to a higher level. It is the use of ultrasound in the treatment, prevention or interruption of disease and disease progression. The ultrasound is directed at specific areas, tissues or organs and delivers an acoustic output that is higher than the output delivered by diagnostic ultrasound equipment. The acoustic waves can heat or break up tumors, knotty or thickened tissue that is pressing on nerves and so on. The hope is that the therapeutic or interventional ultrasound will one day replace many of the surgeries performed today.
Future of Interventional Ultrasound is Almost Here
Ask what ultrasound is all about and it is tempting to think of pictures of fetuses in the womb because that is the use people are most familiar with and the imaging that can add some fun to pregnancy. However, it is just one purpose of ultrasound. Though a critically important tool for monitoring fetal development, anyone thinking of ultrasound as being a mostly obstetrical tool greatly underrates the tremendous use of ultrasound as a medical tool that can treat or heal a variety of medical conditions.
The NIBIB funds high level research projects investigating new applications for ultrasound. The research showcases the future of sonography. Currently, the projects are studying:
- Acoustic Radiation Force Impulse Imaging (ARFI) – Duke University researchers are studying the use of ultrasound elastography for differentiating healthy tissue versus diseased tissue. If the new method is successfully developed and applied, people with liver disease can potentially be spared very painful liver biopsies.
- Histotripsy – At the University of Michigan, researchers are studying the use of High Intensity Focused Ultrasound (HIFU) as a blood clot dissolving tool. The histotripsy is a procedure in which successive high intensity focused ultrasound pulses are used in the mechanical destruction or fractionation of tissue. The intensity of the pulses is a hundred-times higher than the pulses used in diagnostic ultrasound imaging.
- Synergistic combination of acoustic and optic modalities for chronic wound treatment – Drexel University researchers are working on the development of a new technique they call theragnostic which is a combination of the words “therapeutic” and “diagnostic.” The research involves developing a wearable patient patch that can deliver regular low frequency ultrasound therapy for wound healing.
These are just three examples of NIBIB funded research currently ongoing. Others include the ultrasound technologies and strategies for stroke treatments, early detection of ischemia, detection of lymph-node metastases and many more.
Future with No Limits
Understanding the technical details of the how an ultrasound machine works is important. It provides the basics for understanding how to deliver quality patient care during the ultrasound imaging procedure. However, research is leading to the development of equipment and procedures that are going to expand the use of ultrasound as a therapeutic and interventional tool to improve patient care. Future sonographers will play an increasingly important role in assisting physicians with diagnosis, intervention and treatment of disease.