A 2-year-old child shows up to daycare with a bruise on her arm. Her dad dropped her off today, she was at her mom’s house the day before, and she was staying with her grandparents the day before that. All the guardians are pointing fingers at one another. Who is to blame?
“The forensic ability to accurately determine the age of a bruise has long evaded the medical community, which hasn’t been able to answer questions about about how old bruises are with any degree of accuracy,” said Dr. Dale Woolridge, director of the Southern Arizona Children’s Advocacy Center and professor of emergency medicine, pediatrics, and chemistry and biochemistry at the University of Arizona.
In 2018, Woolridge approached Urs Utzinger, associate professor and associate department head for undergraduate affairs in the Department of Biomedical Engineering, about creating a device that could determine the age of a bruise by measuring the way it reflects light. The two decided to sponsor a project in the Engineering Design Program and ask a team of seniors to take the first step toward creating it.
In the Engineering Design Program, teams of four to six seniors spend a year creating industry- and university-sponsored technologies with real-world applications. This team of five biomedical engineers and one mechanical engineer is this year’s only all-woman engineering design team.
In 2017, 72 percent of all child fatalities in the U.S. caused by physical abuse occurred in children younger than 3 years old, according to the U.S. Department of Health & Human Services. Woolridge, who is also director of the Banner Suspected Child Abuse and Neglect program for the Western region, works with these cases regularly, and the idea for a device to age bruises stemmed from his desire to help children. However, such a device could also be used in worker’s compensation cases, domestic violence situations or other circumstances where a person can’t answer questions about who or what caused their bruises.
Blue, Purple, Green and Yellow
Anyone who has ever had a bruise knows its color changes over time, moving through blue, purple, green and yellow tones before fading away.
As Utzinger said, “Most people know that when they have a bruise, they think it’s ugly. Then, it gets uglier,” said Utzinger, who is also an associate professor of obstetrics and gynecology, electrical and computer engineeringand optical sciences, and a member of the UA BIO5 Institute.
“We’re using a specialized camera and, through our software, enhancing the image information in order to better evaluate the color of the bruise,” team member Ghazal Moghaddami said.
The final version of the device will measure just a few inches across and hold a spectrometer, two microprocessors, a display screen and a memory card to hold the data of multiple patients. Social workers and physicians can take measurements by gently applying the portable device to affected skin.
“They’ll take one base measurement to compare the bruise to the person’s regular skin,” team lead Samantha Davidson said. “Then they’re going to take measurements on the bruise itself. The idea is that we’ll be able to remove the memory card and put it in a computer to analyze the data.”
The team members have a broad range of interests: Davidson is going to pursue a master’s degree in epidemiology at the UA; Alexandra Janowski is pursuing a master’s in biomedical engineering. Others have plans to become physicians’ assistants, enter medical school or work in the biotech industry. But they all were drawn to the opportunity to create this device.
“This project could potentially help people,” Davidson said. “I felt like this was going to have an impact.”
They also agree that their experience in the Engineering Design Program helped them learn everything from programming to interpersonal skills, which will help them in any career path they choose.
“Even if you don’t go into engineering, if you go into health, you have a different insight into how things actually work,” team member Claudia Segura Oroz said. “Even if I never work as an engineer, I will know exactly what’s going on and why it’s going on.”
See this project and 117 others at the University of Arizona’s Engineering Design Day on April 29.