Tissue Phantoms Aren’t Just for Crying Ghosts

OReilly FIAt the end of January and beginning of February of this year, over 20,000 people, including authors and presenters for thousands of technical papers, attended the Photonics West conference in San Francisco. This conference was organized by SPIE, the international society for optics and photonics. Thanks to generous support from Northeastern and the conference organizers, I was able to travel from Geneva, where I am currently on my second coop at CERN, to present work that I did during my first coop at Radiation Monitoring Devices, Inc (RMD).

When I started at RMD in January 2016, they were working on a device that utilizes lasers and fiber optics to measure blood flow velocity. This technology can be used to monitor patients at risk of internal bleeding and warn medical staff when they start to go into shock.

In order to get it approved for medical and commercial use, the device has to be rigorously tested. Unfortunately, since it relies on the interaction of light with flesh, the results can vary from person to person due to skin color, muscle tone, water content, and other factors. They can even differ for the same person on different days! For this reason, it is important to have something that will maintain constant optical properties so that the device can be calibrated.

Optical tissue phantoms mimic flesh in the way that it interacts with light and stay the same so that they can be a constant benchmark for research and development of optical techniques. Many materials can be used for this purpose, including Intralipid, which is similar to watered-down milk, and various plastics. I developed a phantom that could be 3D printed and that had tubes running through it similar to the flow geometry of human capillaries. The application that we were studying is concerned with measuring this flow, so the geometry could be important, but nobody had previously done anything to address it.

I presented a poster about the design of this phantom and the results of the tests I ran on it to verify that it could be used to calibrate the blood flow velocity technology. It was great preparation both for graduate school and a career as a researcher to discuss my work with experts in the field and to see what kinds of questions people asked. I met people working at many different institutions on many different facets of biomedical optics, with every step of the basic research to application pipeline represented.

Outside of the poster session, I was able to attend talks given by these experts on topics that I had never even heard of before. One session introduced the diagnostic challenges associated with a certain kind of pulmonary fibrosis and how they might be solved by using novel optical methods. In another, a professor explained how her lab was drawing inspiration from biological systems to design more sensitive transistors.

When not taking in a presentation, I was able to help a team of graduate students, professors, a postdoc, and my supervisor from RMD prepare for all of their various talks and posters. Even this relative down time was edifying, as I learned about best practices for communication with other scientists and how people in many different stages of a research career work and relate to each other.

Attending Photonics West was a great experience enabled by the Honors program. It will be very helpful when it comes time to look for and apply to graduate schools and onward as I progress along a research track. I am very grateful to everyone who enabled me to take advantage of this opportunity, including the Honors and Scholars programs at Northeastern, SPIE, and collaborators from RMD, the University of Michigan, and the University of Miami in Ohio.

Jameson O’Reilly, Mathematics/Physics