Research And Application Of Radioluminescence Imaging

Cerenkov luminescence imaging?CLI?,as a novel optical molecular imaging technique,has a large number of clinically approved radionuclide probes and uses conventional optical imaging devices-electronic multiply charge Coupled device,EMCCD)camera to capture the signal,which has been widely concerned by the researchers.However,Cherenkov light has a very low fluorescence yield and a strong biological tissue absorption rate and scattering rate?spectral distribution in the ultraviolet and blue band?,so it usually takes 3-5 minutes of exposure time to detect the signal.The harsh requirements of the dark environment limit its clinical transformation.For the problem of low intensity and signal-to-noise ratio,a new imaging mode named painted-fullamination radioluminescence imaging?PRLI?is proposed.The method is based on the use of Gd₂O₂S:Tb scintillator material to enhance the signal and improve the signal-to-noise ratio by a sensible screen that can be fully fitted to the surface of the mouse.This hypothesis is verified by a more detailed experiment,and the research on PRLI dynamic imaging is carried out.The main contents of the study include:1)Aiming at the strong impulse noise caused by the long exposure time in the traditional CLI,a time domain median filtering method is proposed to improve the quality of the CLI image.2)A PRLI imaging model was proposed.In order to verify the imaging effect of PRLI,it was compared with traditional CLI and flexible radioluminescence imaging?FRLI?based on flexible sensor screen.The experimental results show that the imaging resolution,signal linearity of radionuclide activity,sensitization screen uniformity,signal enhancement efficiency at different depths and SNR of live breast cancer tumor model.The results show that the signal-to-noise ratio is higher than that of CLI,and the signal-to-noise ratio of live tumor model is higher than that of CLI 1.013 and FRLI 1.173 to 1.559,which can more clearly identify the position of tumor.3)Aiming at the shortcomings of traditional CLI in temporal imaging with low temporal resolution,this paper studied the dynamic monitoring of tumor on the basis of PRLI.The time-activity curves?TAC?of the tumor region and the background region were obtained by manually selecting the region of interest?ROI?according to the tumor outline of the white light image,and the results were compared with those of other studies.?CAM-CM?method was applied to PRLI dynamic imaging.The difference between the tumor and the background TAC was used to separate the tumor from the background.The results showed that the tumor unsupervised extraction,isolation of tumor signals and automatic acquisition of TAC.