Speaker: Andreas Velten, PhD | Associate Professor, Department of Biostatistics & Medical Informatics and Department of Electrical and Computer Engineering, University of Wisconsin-Madison
Date: Monday, November 17th, 2025
Time: 11:10 AM Central Time
Location: Zoom
Title: “Surgical Imaging Photon by Photon”
Abstract:Single photon cameras have pixels that can detect photons and the exact timing of their arrival resulting in cameras with unprecedented capabilities. Concepts like motion blur, exposure time, and dynamic range that are essential to conventional cameras do not really apply to single photon sensors.
These enhanced imaging capabilities are particularly interesting in medical applications with extreme demands, such as Fluorescence Guided Surgery (FGS). FGS methods make use of fluorescent markers that selectively attach to and label different anatomical structures in the human body to make them visible during surgery. Labels for vasculature, tumors, and nerves are under investigation. Imaging systems need to work with weak signals in moving scenes covered by bright ambient light. We are applying a series of computational imaging improvements to allow our cameras to produce image qualities during surgery that used to only be achievable in static scenes in a dark laboratory.
Single photon cameras can also enable future FGS methods by capturing fluorescence lifetime. The nanosecond scale fluorescence lifetime of a fluorescent marker is related to the markers surroundings and molecular binding partners. By measuring lifetime we may better differentiate between marker molecules that are actually bound to the target site and those that are floating freely. It is also possible to perform label free FGS by making use of fluorescent molecules that are naturally present in human cells.
Bio:Andreas Velten is Associate Professor at the Department of Biostatistics and Medical Informatics and the Department of Electrical and Computer Engineering at the University of Wisconsin-Madison and directs the Computational Optics Group. He obtained his PhD in Physics at the University of New Mexico in Albuquerque and was a postdoctoral associate of the Camera Culture Group at the MIT Media Lab. He has been included in the MIT TR35 list of the world’s top innovators under the age of 35 and is a senior member of NAI and SPIE as well as a fellow of Optica. He is co-Founder of Onlume, a company that develops surgical imaging systems, and Ubicept, a company developing single photon imaging solutions.