Fig. 1. Block diagram of device system design

Fig. 2. Traditional “L” optical structure of fluorescent detection

Fig. 3. Improved optical structure of fluorescent detection

Fig. 4. Comparison of photoelectric conversion efficiency of 1 mm² CMOS/PD and SIPM. (a) PD/CMOS; (b) SIPM

Fig. 5. Design of high signal-to-noise ratio photoelectric conversion amplifier circuit

Fig. 6. Equivalent model of photoelectric sensor

Fig. 7. Indocyanine green and parathyroid fluorescence spectra. (a) Fluorescence spectra of parathyroid glands and other tissues; (b) ICG fluorescence spectra

Fig. 8. Fiber-optic probe and fluorescent reagent fixation tool

Fig. 9. Linear relationship between fluorescence intensity and ICG concentration

Fig. 10. Infrared fluorescence imager host and disposable optical fiber probe

Fig. 11. Fiber probe directly contacted the suspected parathyroid to obtain fluorescence intensity

Fig. 12. Comparison of fluorescence intensity between parathyroid gland and other tissues

Fig. 13. Pathological analysis confirmed parathyroid tissue

Fig. 14. Comparison of fluorescence intensity between parathyroid gland and other tissues^[19]