Studies increasingly support the idea that fluorescence lifetime imaging (FLI) offers superior tumor detection contrast, but conventional methods are limited by low frame rates and high computational load. We present a compact, real-time FLI system based on a QVGA SPAD sensor with in-pixel switched-capacitor circuits that compute the average photon time-of-arrival in the analog domain. This single-shot, center-of-mass approach avoids photon binning and gated integration, enabling high frame rate FLI up to 30 FPS. Experimental validation with visible (fluorescein and acridine orange) and near-infrared fluorophores (ICG and IRDye800CW), confirms accurate performance. Future work will evaluate the system in preclinical in vivo settings for fluorescence-guided surgical applications.
Nevens, W, Lapauw, T, Van Den Dries, T, Vrijsen, JEJ, Ingelberts, H & Kuijk, M 2026, 'A single-shot SPAD-based center-of-mass fluorescence lifetime imaging system for real-time surgical applications', Proceedings of SPIE, the International Society for Optical Engineering, vol. 13832. https://doi.org/10.1117/12.3078594
Nevens, W., Lapauw, T., Van Den Dries, T., Vrijsen, J. E. J., Ingelberts, H., & Kuijk, M. (2026). A single-shot SPAD-based center-of-mass fluorescence lifetime imaging system for real-time surgical applications. Proceedings of SPIE, the International Society for Optical Engineering, 13832. https://doi.org/10.1117/12.3078594
@article{b723e0abf126431f920fc185c32ab4f1,
title = "A single-shot SPAD-based center-of-mass fluorescence lifetime imaging system for real-time surgical applications",
abstract = "Studies increasingly support the idea that fluorescence lifetime imaging (FLI) offers superior tumor detection contrast, but conventional methods are limited by low frame rates and high computational load. We present a compact, real-time FLI system based on a QVGA SPAD sensor with in-pixel switched-capacitor circuits that compute the average photon time-of-arrival in the analog domain. This single-shot, center-of-mass approach avoids photon binning and gated integration, enabling high frame rate FLI up to 30 FPS. Experimental validation with visible (fluorescein and acridine orange) and near-infrared fluorophores (ICG and IRDye800CW), confirms accurate performance. Future work will evaluate the system in preclinical in vivo settings for fluorescence-guided surgical applications.",
keywords = "Fluorescence, Fluorescence lifetime, fluorescence lifetime imaging, SPAD, single-photon avalanche diode, Fluorescence-guided surgery",
author = "Wannes Nevens and Thomas Lapauw and \{Van Den Dries\}, Thomas and Vrijsen, \{Jonathan Ernest J\} and Hans Ingelberts and Maarten Kuijk",
note = "Publisher Copyright: {\textcopyright} SPIE.; SPIE BiOS 2026 : Molecular-Guided Surgery: Molecules, Devices, and Applications XII ; Conference date: 19-01-2026",
year = "2026",
month = mar,
day = "5",
doi = "10.1117/12.3078594",
language = "English",
volume = "13832",
journal = "Proceedings of SPIE, the International Society for Optical Engineering",
issn = "0277-786X",
publisher = "Society of Photo-optical Instrumentation Engineers",
}