Ultrasound Provides a "World of Infinite Possibility" to Insana

Michael Insana, full-time faculty member in the Bioimaging Science and Technology Group, develops novel ultrasound techniques and instruments for imaging soft tissue microstructure, elasticity, and blood flow in order to understand basic biological mechanisms, disease progression, and therapeutic responses.

A professor of bioengineering and head of the Ultrasonic Imaging Laboratory at Beckman, Insana is interested in what he knows as “image science.”

“In medicine, imaging provides windows into the body that indicate everything from large anatomical changes to molecular signaling among cells,” said Insana. “It is a world of infinite possibility and relevance that has held my attention for more than 30 years.”

Ultrasound, according to Insana, is fast, safe, and inexpensive. Although known primarily for its use in obstetrics and for cardiovascular assessments, ultrasound technology has vastly advanced in recent years, Insana explained. Because of technical advancements leading to high-resolution images and better tissue contrast at high frame rates, ultrasound can be used in numerous ways not thought of previously.

Researchers in imaging are also interested in big data, said Insana.

“In medical imaging, the images contain much more information than we typically use to diagnose patients,” said Insana. “For example, what could we learn about variations in physiological properties among the population so we could better define what is normal and abnormal?”

“In the past five years, I have become interested in understanding the principles that govern the behavior of large complex systems, like the human body,” said Insana. “The science and engineering in imaging science and large complex systems are similar.” -Michael Insana

Insana cautions that patient privacy must always be considered in the research.

“Currently we determine what information is needed for diagnosis and then go out and acquire it. Yet maybe that acquisition, in the form of patient images and medical records, can teach us what is most important about health and disease. New types of machine-learning algorithms, like those used in computer vision to recognize faces in a crowd, are mining image data in ways that allow us to discover the biomarkers of health.”

Insana is working with Jamshid Ghaboussi from the Department of Civil and Environmental Engineering, and Cameron Hoerig, a student in the Department of Bioengineering, to develop informational modeling techniques that probe patients and let the tissue deformation and force patterns on the patient’s skin tell them about the mechanical properties of tissues below. 

“It costs society a tremendous amount of money to acquire patient data each year,” said Insana. “In the future we hope machine intelligence techniques will help us squeeze every drop of important information from that investment.”

Insana also investigates the fundamentals of imaging system design and performance evaluation, signal processing, detection, and estimation. He and his team have been developing applications for imaging the elasticity of breast tissue, a diagnostic technique for the noninvasive visualization of soft tissue stiffness, for detection of disease progression.

“In the past five years, I have become interested in understanding the principles that govern the behavior of large complex systems, like the human body,” said Insana. “The science and engineering in imaging science and large complex systems are similar.” 

Insana and his collaborators have worked with radiologists to find diagnostic features commonly used to diagnose disease; then they express those features mathematically and enhance diagnostic performance and data processing using statistical decision theory and optimal strategies for data processing.

The techniques and instruments that Insana has been developing help in understanding, for example, the basic mechanisms of cancerous lesion formation, metastatic progression, responses to therapy, and sources of image contrast.

In 2007, Insana ran a pilot study looking at a fast, inexpensive, and safe way to image breast-tissue elasticity using ultrasound.

“Changes in tissue stiffness are often early indicators of the inflammation associated with precancerous conditions,” said Insana. “We performed a pilot study at the University of California-Davis in Sacramento because of my connections there. Of the 21 patients studied, and, much to everyone’s surprise, we correctly diagnosed every lesion when comparted to biopsy results.”

Insana’s project, SAVE (Sub-Hertz Analysis of Viscoelasticity), is continuing at Mayo Clinic, with support from the National Institutes of Health.

“We are continuing to refine and expand the study to make the technique reliably in any clinical environment,” Insana explained. “As expected, there are challenges in applying a small uniform compressive force and accurately tracking tissue movements. We have acquired more patient data and continue to be optimistic that we can achieve reliably reproducible results. 

“It’s a little like watching ants on an ant hill without your glasses,” Insana explained. “You can see that things are moving but it’s hard to make out exactly where each ant is going. The ‘ants’ in tissue elasticity images are tissue parts that are too small to see in the ultrasound images.

Through image processing programs, we can clarify the movement significantly, and then we can estimate mechanical properties.”
In addition to improving the detection and treatment of breast cancer, the research could also be applied to vascular and kidney diseases.

Insana has recently filed a patent disclosure with Sara Bahramian, a student in electrical and computer engineering, for a technique that enhances the appearance of microcalcifications in breast lesions.

“Often microcalcifications, tiny bits of bone, grow in aggressive breast cancers as the body tries to quickly build new blood vessels using a wound healing mechanism,” said Insana. “X-rays see these well, but ultrasound doesn’t. Since we study imaging systems by tracking the flow of patient information, we were able to find a point where information was lost. That lost information is vital to enhancing breast cancer detection using sonography.”   

Insana was recently award a Willett professorship from the College of Engineering at Illinois. He was recognized for his contributions to translational research in the development of novel ultrasonic instrumentation and methods for imaging soft tissue microstructure, viscoelasticity, and blood flow.

From the archives
Watch a video from a 2009 interview with Insana: