Journal of Biomedical Optics
Obtaining accurate quantitative information on the concentration and distribution of fluorescent markers lying at a depth below the surface of optically turbid media, such as tissue, is a significant challenge. Here, we introduce a fluorescence reconstruction technique based on a diffusion light transport model that can be used during surgery, including guiding resection of brain tumors, for depth-resolved quantitative imaging of near-infrared fluorescent markers. Hyperspectral fluorescence images are used to compute a topographic map of the fluorophore distribution, which yields structural and optical constraints for a three-dimensional subsequent hyperspectral diffuse fluorescence reconstruction algorithm. Using the model fluorophore Alexa Fluor 647 and brain-like tissue phantoms, the technique yielded estimates of fluorophore concentration within ±25% of the true value to depths of 5 to 9 mm, depending on the concentration. The approach is practical for integration into a neurosurgical fluorescence microscope and has potential to further extend fluorescence-guided resection using objective and quantified metrics of the presence of residual tumor tissue.
Jermyn, Michael; Kolste, Kolbein; Pichette, Julien; Sheehy, Guillaume; Angulo-Rodriguez, Leticia; Paulsen, Keith D.; Roberts, David W.; Wilson, Brian C.; Petrecca, Kevin; and Leblond, Frederic, "Macroscopic-Imaging Technique for Subsurface Quantification of Near-Infrared Markers During Surgery" (2015). Open Dartmouth: Faculty Open Access Scholarship. 3743.