Feasibility of using spatial frequency domain imaging to aid in fluorescence guided resection (Conference Presentation)

Abstract

The goal of fluorescence-guided surgery (FGR) is to provide real-time enhancement of tumors to maximize safe resection. The optical property mapping ability of spatial frequency domain imaging (SFDI) has enabled quantitative fluorescence imaging (qFI) of protoporphyrin IX (PpIX) in gliomas in the pre-clinical setting. The goal of this study was to evaluate the feasibility of using SFDI to allow for qFI to enhance FGR. Specifically, we modified a benchtop SFDI system to mount directly to a commercial surgical microscope(Zeiss). A commercially available digital light processing module (DLI Austin, TX) was used to modulate light from a xenon arc lamp to illuminate the field. White light excitation and a liquid crystal tunable filter (LCTF Verispec) was used to measure diffuse reflectance at discreet wavelengths from 420 nm to 720 nm on a CMOS camera. An illumination side filter wheel allowed for excitation of PpIX fluorescence at 405 nm and 635 nm and the LCTF measured fluorescence emission at 670 nm and 710 nm. The ability of the clinical microscope to perform optical mapping and qFI was tested with tissue simulating phantoms and live mouse models. The results of these tests showed that SFDI can be implemented in a clinical microscope and the optical mapping and qFI abilities of SFDI may be used to enhance FGR.