Tag Archives: American Institute of Ultrasound in Medicine

Focused Ultrasound as a Therapeutic Tool

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Ultrasound, long regarded as a diagnostic mainstay, is now poised to reshape how the medical community approaches treatment, particularly in the field of neurology. In a keynote presentation at the American Institute of Ultrasound in Medicine (AIUM) annual meeting, Dr. Ali Rezai of West Virginia University offered a compelling overview of how focused ultrasound is rapidly gaining traction as a therapeutic tool. His message was clear: the future of ultrasound will not be limited to imaging. It will play an increasingly vital role in treating complex brain disorders.

Used with permission from AuntMinnie.com

The use of focused ultrasound, whether high- or low-intensity, is opening new avenues in managing diseases like Parkinson’s, Alzheimer’s, epilepsy, and even addiction. These technologies deliver targeted soundwaves to precise regions of the brain, allowing clinicians to modify neural activity, open the blood-brain barrier for drug delivery, or ablate diseased tissue, all without a surgical incision.

High-intensity focused ultrasound (HIFU), which uses frequencies ranging from 20 kHz to 200 MHz, is already being used to treat patients with movement disorders such as essential tremor and Parkinson’s disease. The procedure is performed under MRI guidance, with patients wearing a specialized helmet containing around 1,000 ultrasound transducers. These transducers concentrate energy on specific brain structures involved in abnormal motor control. According to Dr. Rezai, patients often see immediate improvement, regaining function within hours and returning home the same day, an outcome that significantly reduces both recovery time and risk.

On the other end of the spectrum, low-intensity focused ultrasound (LIFU) is being investigated for its ability to transiently open the blood-brain barrier, which is a major challenge in the treatment of central nervous system conditions. This technique allows therapeutic agents that would otherwise be blocked to reach their targets more effectively. One area of active research is Alzheimer’s disease. Clinical trials suggest that LIFU can reduce amyloid plaque burden, a hallmark of the disease, simply by enabling targeted delivery or enhancing the brain’s own clearance mechanisms. In one study led by Dr. Rezai, patients receiving both focused ultrasound and anti-amyloid antibody therapy experienced greater reductions in plaque levels with minimal side effects.

LIFU is also being explored for neuromodulation—altering brain activity to treat psychiatric and behavioral disorders. By targeting deep brain structures involved in reward and craving, ultrasound has the potential to help patients with substance use disorders or behavioral addictions. Preliminary data from a small clinical study show that even a single treatment session aimed at the brain’s nucleus accumbens reduced cravings, with some patients reporting sustained effects.

Dr. Rezai emphasized that these breakthroughs are not theoretical. His team at the Rockefeller Neuroscience Institute is performing these procedures weekly, and demand is increasing. “We’re in desperate need for therapeutic strategies because people are living longer,” he said.

As this field matures, the implications extend far beyond traditional neurology. Focused ultrasound for therapeutic use is drawing interest from neurosurgeons, psychiatrists, biomedical engineers, and data scientists. The integration of real-time imaging, precision targeting, and noninvasive energy delivery makes it a uniquely versatile platform. It may not be long before therapeutic ultrasound becomes a standard tool in multidisciplinary care, ushering in a new era where sound not only reveals what’s happening inside the body but also helps restore function and quality of life.

The future is very bright for therapeutics and using focused ultrasound
— Dr. Ali Rezai

Cynthia Owens, BA, is the Publications Coordinator for the American Institute of Ultrasound in Medicine (AIUM).

To Treat or Not to Treat – That is the Question!

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What if your newborn has a patent ductus arteriosus?

Some might ask, what is a ductus arteriosus?

During fetal development, a patent ductus arteriosus (PDA, see Figure) is important for diverting well-oxygenated blood returning from the placenta past the fluid-filled lungs and directly into the systemic circulation in order to perfuse organs.

Blood Flow with Patent Ductus Arteriousus

A patent ductus arteriosus allows for diverting aortic blood to flow into the lungs and thus pressurize the pulmonary circulation as well as allow for deoxygenated blood to enter into the aortic arch if the flow is reversed. Very low birth weight infants are prone to this condition and choice of appropriate treatment is in question. Image provided by Blausen.com.(4)

In full-term newborns, the PDA closes within two days of birth by means of vasoconstriction and anatomic remodeling.(1) Or it doesn’t. In 65% of premature infants born at 30 weeks’ gestation or less, the PDA fails to close within the first 7 days.(2, 3) Therefore, the pulmonary and systemic circulations remain connected. Consequently, blood is shunted away from the general systemic circulation to the lungs and can lead to severe flow-related problems such as central nervous system ischemia and hemorrhage, necrotizing enterocolitis, and renal failure. Such a Patent Ductus Arteriosus (PDA) leads to the ultimate question of to treat or not to treat? The two schools of thought in neonatology are watchful waiting, treating with nonsteroidal anti-inflammatory drugs (NSAID) or an invasive procedure to close the ductus.

Possible concerns are multifactorial. Intervention risks side effects from medications and procedural complications. Watchful waiting risks diminished blood and oxygen supply to the brain and abdominal organs. Quantifying blood flow and oxygen supply in these fragile humans is nearly impossible, especially since most of them are actually very low birth weight babies (VLBW, i.e. <1,500 grams). They are tiny.

In rare cases, clinicians use MRI to image and quantify PDA and carotid flow. That, however, requires specialized facilities in which the neonates can remain in their protective incubators while being in the magnet.

Imagine you could use ultrasound to assess not only the PDA but also the blood flow to the brain and the abdomen. Ultrasound is the ideal modality as it is non-ionizing, can be used at the bedside and is already a part of neonatal care. Yet, assessing blood flow quantitatively using 2D pulsed-wave ultrasound has been a challenge in and of itself. It not only requires user-selected angle correction as well as lumen diameter measurements but also neglects flow outside of the 2D image plane. Others may use simple velocity measurements or surrogate markers, but those do not represent flow.

A possible solution has been proposed by our group at the University of Michigan (UM). It is using 3D ultrasound to employ Gauss’ Theorem to quantify flow. While high-frequency ultrasound is excellent for VLBW babies, imaging a 1-mm diameter PDA lumen may still be a challenge. The UM team has previously shown the benefits of 3D color flow for quantification of blood flow. We hypothesize that even a PDA lumen could be assessed accurately, despite its challenging diameter. In addition, if successful, clinicians should be able to measure flow in the PDA within 6 seconds after obtaining a cross-sectional color flow image of the PDA with minimal to no user dependence. This presupposes a 2D matrix array capable of recording 5 color flow volumes per second.

In an American Society of Echocardiography (ASE) and AIUM co-sponsored investigation (E21 and EER funding), we will assess the effects of PDAs before and after treatment. Baseline blood flow for cardiac output, total brain blood flow, blood flow to the small intestines, and renal blood flow will be determined in full-term healthy neonates. An inter- and intraoperator variability study will be employed to warrant scientific rigor and target an end-organ flow estimation with <10% variation for test-retest and <10% between operators. Blood flow measurements in VLBW cohorts scheduled for intervention will yield estimates before and after intervention and thus provide insight in the predictive value for this method.

The ultimate goal is that 3D ultrasound will help caregivers to determine if adequate flow to end organs exists and if intervention is required. Furthermore, stable and unstable VLBW cohorts can possibly be differentiated by their flow to end organs and through the PDA. Thus, answering the question of whether to treat or not to treat.

Principle Investigators: Oliver D. Kripfgans, Ph.D. and Jonathan M. Rubin, M.D., Ph.D.
Co-Investigators: Gary Weiner, M.D. and Marjorie C. Treadwell, M.D.

References:

  1. Deshpande P, Baczynski M, McNamara PJ, Jain A. Patent ductus arteriosus: The physiology of transition. Semin Fetal Neonatal Med 2018;23(4):225–231. doi: 10.1016/j.siny.2018.05.001
  2. Clyman RI, Couto J, Murphy GM. Patent ductus arteriosus: are current neonatal treatment options better or worse than no treatment at all? Semin Perinatol 2012;36(2):123–129. doi: 10.1053/j.semperi.2011.09.022
  3. Egbe A, Uppu S, Stroustrup A, Lee S, Ho D, Srivastava S. Incidences and sociodemographics of specific congenital heart diseases in the United States of America: an evaluation of hospital discharge diagnoses. Pediatr Cardiol 2014;35(6):975–982. doi: 10.1007/s00246-014-0884-8
  4. Blausen.com staff (2014). “Medical gallery of Blausen Medical 2014”. WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436.

 

Oliver D. Kripfgans, PhD, FAIUM, is a Research Associate Professor in the Department of Radiology at the University of Michigan. Jonathan Rubin, MD, PhD, FAIUM, is a Professor Emeritus in the Department of Radiology at the University of Michigan.

 

Comment below, or, AIUM members, continue the conversation on Connect, the AIUM’s online community to share your experience.

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Money, Politics, and Ego

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The AIUM is a unique organization of professionals passionate about the capabilities and potential of ultrasound to help our patients. With the annual convention freshly over, and a long list of things to work on for next year, I’ve been thinking about the AIUM and why it’s an important group for me.

Although the AIUM is not the primary organization for any of us, that’s what is special and interesting about the AIUM. We all belong to our separate subspecialty interest groups, our tribes, where there is familiarity and comfort in being surrounded by people who are like us, and do what we do, and think like we do. But what other society do you belong to that has the mix of medical and surgical specialties, sonographers, scientists, residents, students, and industry partners? The AIUM’s 19 communities and interest groups cover a diversity of interests and practices and bring people together that in the “real world” of our day-to-day work may find themselves at odds with each other.

ColeyAnd that’s the challenge of the AIUM: to be our best and fulfill our mission of providing the best ultrasound imaging care to our patients means that we have to set aside (at least in part and as best that we can) issues of money, politics, and ego.

This is not always easy.

The world around us is often not encouraging toward cooperation and service to ideals greater than immediate self-interests.

But that’s what AIUM members try to do. Even if it isn’t easy.

If you attended the recent convention in Orlando, I hope that you spent some time attending sessions or talking to people from outside your main area of interest. That’s an opportunity that you just can’t get at other meetings: to exchange ideas and excitement, to challenge and provoke, and ultimately a chance to learn and advance both personally and as medical professionals.

Similarly, the next time you pick up a copy of the Journal of Ultrasound in Medicine, read an article in an area that you don’t practice. Even if you can’t appreciate the nuances, appreciate the creativity of the work and the varied applications of ultrasound in medicine. There are a lot of bright people out there doing cool things. I would especially recommend reading the basic science articles. The technology, instrumentation, and techniques that we take for granted come from here. You may not fully grasp them any more than I do, but this is where the big leaps are going to come from, and it’s good to know what could be just over the horizon.

I hope that you’ll get as much out of the AIUM as I have over the years. I hope that you’ll step out of your comfort zone and talk with people from other disciplines and interests. I hope that you’ll ask questions and get involved. I hope that the AIUM helps you learn and grow, and that you will help the AIUM to figure out how to do that well. If we can do this together, then we and our patients will be the better for it.

What about your AIUM membership do you find most valuable? How do you benefit from the diversity of medical specialties within the AIUM? Comment below or let us know on Twitter: @AIUM_Ultrasound.

Brian Coley, MD, AIUM President (2017–2019), is radiologist-in-chief and the Frederic N. Silverman chair for pediatric radiology at the Cincinnati Children’s Hospital Medical Center, as well as professor of radiology and pediatrics at the University of Cincinnati College of Medicine.