Physicians have been using conventional ultrasound, also called b-mode ultrasound, for diagnostic imaging since the 1970s. However, over the past 10 years there have been significant technological improvements within the equipment, as well as development of new technologies that allowed ultrasound to become extensively adopted. Ultrasound equipment has gotten physically smaller, generates less heat and has become more power efficient. These upgrades, together with vast enhancements in image quality, have pushed ultrasound into the point-of-care setting. Point-of-care ultrasound has become widely performed in emergency rooms, PCP offices and obstetric practices. As healthcare reform continues to favor the usage of more inexpensive solutions, this trend is expected to persist until ultrasound is used in every single doctor’s office.
Today, ultrasound images can be purchased with higher resolutions, allowing physicians to see much clearer definition. “Everyone is used to ultrasound pictures being fuzzy,” said Tomo Hasegawa, director, ultrasound business unit, Toshiba America Medical Systems. “With enhancement in computer systems doing real-time processing, we’re starting to get images which are so clear, people don’t even realize it’s ultrasound.”
Anthony Samir, M.D., associate medical director, ultrasound imaging, Massachusetts General Hospital, said these improvements might be credited to upgrades in ultrasound equipment. “The b-mode technologies have improved enormously with regards to transducer sensitivity, the beam former, image processing speed and the caliber of the last data display,” he explained. These improvements have resulted in a picture quality in b-mode imaging that is preferable to it absolutely was even ten years ago. Physicians can see things that are much smaller along with a lot deeper than was previously possible. “We can easily see flow in vessels as small as 2 mm in diameter in organs like the kidney and lymph nodes.”
Due partly to such image-quality improvements, ultrasound is now being used in interventional procedures generally dominated by computed tomography (CT) and magnetic resonance imaging (MRI). And although many interventional physicians still count on CT and MRI for lung procedures, it has become common for interventionalists to use ultrasound as opposed to CT for image-guided biopsies and ablations.
Volumetric ultrasound has additionally continued to boost. Ultrasound was previously only able to capture just one imaging plane, however nowadays it could acquire volumes. “Transducers that permit for that acquisition of real-time volumes of tissue allow us to image in multiple planes – for instance, the transverse and sagittal dimensions – simultaneously,” Samir said. While volumetric ultrasound has been doing development for several years, the transducers have only been designed for conventional use for the last few years. And furthermore, as volumetric ultrasound allows physicians to characterize tissue a lot better than before and perform conventional procedures with much greater accuracy, this region of ultrasound will continue to grow.
Newer technologies are set to revolutionize ultrasound technician. One particular technology is sonoelastography, a technique which has been in development for pretty much two decades. Sonoelastography utilizes the same machine that does b-mode ultrasound to measure tissue stiffness. Its dimensions are the mechanical characteristics of tissues then displays qmdirp mechanical characteristics overlaid on the conventional b-mode ultrasound image. By giving physicians the ability to see stiffer and softer areas within the tissue, sonoelastography will assist in liver fibrosis staging, thyroid nodule, lymph node and indeterminate breast lump characterization, and the detection of prostate cancer, all of these can not be completed with conventional ultrasound. Elastography has become obtainable in Europe for a while and systems in america started receiving U.S. Food and Drug Administration (FDA) approval in the last year.
Another recent development is the use of ultrasound contrast agents. Contrast-enhanced ultrasound (CEUS) has been available in Canada, Australia, China and Europe for a number of years, but has not been available in the United States outside of echocardiography. CEUS grants far more sensitivity for that detection of tumors, allowing ultrasound use to expand into many of the functions currently performed by CT and MRI.
Healthcare reform as well as other legislation is playing a large role in the widespread adoption of ultrasound. This could be observed in the legislation that numerous states have passed requiring radiologists to inform women should they have dense breasts, and also to inform them of some great benefits of supplemental screening.