At 14, Bell enrolled within the extremely selective Brooklyn Technical Excessive College, the place she divided her time between lecturers and a newfound curiosity in working; she was, as she places it, “aggressive in monitor and aggressive at school.” Throughout her sophomore yr, she participated in a program designed to introduce ladies to engineering—and was hooked. “I fell in love with engineering by means of that program,” she says.
As soon as she’d set her sights on changing into an engineer, Bell says, her brother, Abdul-Rahman Lediju (who’s now an lawyer), directed her consideration to the Institute. “He was the one who instructed me about MIT,” she says, remembering her pleasure. “I assumed: ‘I need to treatment most cancers and AIDS—and I’ll get to do math there!’”
At 18, Bell already knew she wished to give attention to biomedical engineering, however on the time it was solely provided as a minor, so she majored in mechanical engineering. “Simply wanting on the trajectory of the curriculum, I knew it was a method to get a basis in how one can make stuff basically,” she says, remembering the sequence of programs, from Mechanics and Supplies to Measurement and Instrumentation. “I knew I might be taught biomedical engineering later. For me it was the right setup.”
In her junior yr, whereas Bell was making her approach by means of that curriculum, her mom died of breast most cancers. The loss solidified her curiosity in most cancers analysis and clarified her educational path ahead. “I wished to make use of every thing I discovered at MIT, and I wished to avoid wasting lives,” she says. “So I moved to early detection and ultrasound as the very best software, when it comes to security, portability, and cost-efficiency.”
Bell discovered the suitable subsequent step at Duke College within the lab of biomedical engineer Gregg Trahey, whose work focuses on creating new ultrasound applied sciences. She knew his lab was the perfect match regardless that she jokes, “I most likely scared him with how direct and targeted I used to be.”
Bell remembers her pleasure on the prospect of going to MIT. “I assumed: ‘I need to treatment most cancers and AIDS—and I’ll get to do math there!’”
Throughout her first yr in Trahey’s lab, Bell investigated what’s often known as acoustic muddle—random noises or artifacts which might be recorded and translated into ultrasound photos and may intervene with their readability and usefulness. “It makes it troublesome to establish buildings of curiosity,” she explains.
However an answer quickly introduced itself. Bell realized that when the movement of an ultrasound probe induced the belly wall to maneuver whereas, say, the bladder was being imaged, a few of these acoustic artifacts “moved” within the picture too. Analyzing that motion led to methods of filtering out that muddle, leading to clearer ultrasonic photos with higher contrast-to-noise ratio, one of many primary metrics of ultrasound picture high quality. “What’s left behind is the construction itself,” she says.
One in all Bell’s pioneering discoveries got here throughout her last years at Duke, the place she developed a way often known as short-lag spatial coherence beamforming. In ultrasonography, sound waves are transmitted by means of the physique, and echoes that bounce off inside organs are used to type photos of them. These photos, historically, are created by means of a course of often known as “delay and sum” beamforming—a signal-processing algorithm that converts the acoustic echoes captured or obtained by an ultrasound transducer into a picture that’s displayed.
