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Team Members:
  • Santiago Balza
  • Gabrielle Grifno
  • Disha Mishra
  • Yujin Park
  • Shihab Rahman
  • Victor Wang
  • Lucy Wu
  • Jack Yue
  • Nicholas Durr, PhD
  • Keith Aziz, MD
  • Jason Hammond, MD
  • David Weiner, MD
  • Carter Freiburg, MD
  • Anthony Ho, BS


Peripheral arterial disease (PAD) is a condition which results in reduced blood perfusion (blood flow) to the legs. 600,000 PAD patients require revascularization surgery annually and are monitored post-surgery for poor perfusion, which indicates surgical complications. Without timely detection of these complications, consequent widespread tissue death in the legs can lead to amputation. Current technologies used to monitor perfusion post-surgery are heavily skill dependent, costly, or have long wait times, and thus often fail to alert clinicians to insufficient perfusion in a timely manner. If the early onset of low blood perfusion can be easily, inexpensively and reliably detected, vascular surgeons would be able to successfully re-intervene and correct surgical complications for more patients, thus avoiding amputation of a limb that can no longer be salvaged.

Our solution to fill this need for a reliable, accessible tool for perfusion monitoring is EchO2, a handheld device that uses cloud computing to measure perfusion from captured video of a patient’s skin. The device has a screen that displays a dynamic visualization of perfusion which allows clinicians to quickly and easily identify areas that have insufficient blood flow without additional specialized training. Furthermore, EchO2’s minimal output wait time allows clinicians access to a high throughput system: more patients can be monitored with higher frequency than the current standard, drastically reducing the chances that a patient’s condition will critically decline without being detected.

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