Abstract: A method for intraoperatively determining a degree of parathyroid perfusion includes identifying parathyroid tissues of a living subject using autofluorescence detection with a fiber optic probe based fluorescence detection system; administering to the living subject a contrast agent with a dose; after a period of time of the administration, detecting fluorescence in an area of the parathyroid tissues with the fiber optic probe based fluorescence detection system, where the fluorescence is emitted from the contrast agent; and obtaining a detection level and/or a detection ratio for the parathyroid tissues from the detected fluorescence so as to determine a degree of parathyroid perfusion of each parathyroid. The method is not only unaffected by ambient light, but also has no need of images of the parathyroid tissues.

Abstract: The invention discloses systems and methods for providing anatomical guidance in surgery. The system includes a light source configured to emit light for illuminating tissues of a target region; means for obtaining autofluorescence signals emitted from the illuminated tissues in response to the illumination; and a controller configured to process the obtained autofluorescence signal to identify target tissues.