Motorized photoacoustic holder of
biomedical imaging system

Purdue research groups enhancing medical imaging with optical innovations

August 31, 2018
by John R. Fischer, Senior Reporter
Two separate research groups at Purdue University are setting out to improve medical imaging with respective developments of a biomedical imaging system composed of ultrasound and optical technology, and 3D printed, optical phantoms.

Utilizing photoacoustic tomography, the biomedical imaging system will enhance clinical care for patients through improved diagnosis of life-threatening diseases, particularly cardiovascular disease, cancer and diabetes, which together add up to $718 billion a year in the U.S., according to the Centers for Disease Control and Prevention.

“The nice thing about photoacoustic tomography is the compositional information,” Craig Goergen, an assistant professor in Purdue’s Weldon School of Biomedical Engineering, said in a statement. “It provides information about where blood and lipid are located, along with other essential information.”

A noninvasive technique, photoacoustic tomography involves the transmission of pulsed light into the body tissue to create a small increase in temperature that causes tissue to expand and generate an acoustic signal that can be detected by an ultrasound transducer for the visualization of the tissue.

Use of the system can be applied to many tasks, including the mapping of lipid deposition within an arterial wall for the measurement of cardiac tissue damage and tumor biopsies. Applying photoacoustic tomography to intraoperative tumor biopsies enables surgeons to remove all cancer from a patient.

It also requires no contrast agents to depict real-time compositional information of the body tissue, and is equipped with a motorized photoacoustic holder for easy maneuvering and aim of the device. This enables the depth of the solution to be tuned to where the light is focused, improving light penetration depth and signal-to-noise ratio compared to conventional optical techniques.

3D printed, optical phantoms

To ensure that imaging techniques in general are performed at maximum efficiency, a new method for the production of optical phantoms from 3D printers is also under evaluation, with researchers of that collective utilizing technology from Purdue to create the objects.

Containing optical properties designed to match those of biological tissues, the phantoms ensure that machines are correctly calibrated, a task that must be performed by providers on a regular basis to ensure their equipment is running at top performance.

3D printed phantoms can be adapted for multiple imaging techniques in contrast to ones designed through injection mold methods, which shape the object in accordance with the mold geometry,

“We wanted to find a better way to create the phantoms that are used with imaging machines,” Brian Bentz, a Purdue alumnus and Starfish Engineering LLC’s chief executive officer involved in developing the technology, said in a statement. “3D printing is fast and allows us to create complex phantoms with various shapes to ensure the best possible performance for imaging devices.”

Like Bentz, Goergen says the focus of either project is enhanced care for patients. “Trying to diagnose these diseases at an earlier time can lead to improved patient care. We are in the process now of trying to use this enhanced imaging approach use a variety of different applications to see what it can be used for.”

Both research groups worked in conjunction with the Purdue Office of Technology Commercialization for patents. The optical ultrasound group currently has one pending, and is seeking out possible companies to partner with in the use of their technology.

The findings of the optical ultrasound group were published this month in the journal Photoacoustics, with its research funded by the National Institutes of Health.