Application Study Of Synchrotron Radiation Imaging In The Diagnosis And Treatment Of Pancreatic Cancer

The study of synchrotron radiation imaging in evaluation of pancreatic cancer angiogenesisObjective: To investigate the application value of synchrotron radiation imaging in the evaluation of pancreatic cancer angiogenesis.Methods:Xerograph pancreatic cancer model was established via implantation of the fragment of human pancreatic cell line Bx PC-3 into BABL/c nude mouse.Nano-barium sulfate solution was injected into the systemic circulation through the left common carotid artery 10,15,20,25 and 30 days after implantation.Synchrotron radiation imaging(SRI)was obtained with object-detector distance of 10 mm,pixel size of 9μm and the energy of 19 ke V.SRI results of 6 samples were realized at each time point and then the images were taken tomography and tri-dimensional reconstructions.Quantitative analysis was realized with MATLAB software system by measuring the tumor vessels density,the proportion and the length of vessels with different diameters.The histology analysis was performed after SRI.Results : SRI could revealed the morphology and tri-dimensional structure of the pancreatic cancer vessels with caliber more than 10μm.The tumor vessels growth-time curve could be depicted by using quantitative analysis.Over time,the number of tumor vessels and the tumor size increased rapidly,but the tumor vessels developed slowly than the tumor size,which led to the decrease of tumor vessels density.Significant negative linear correlation was revealed between the tumor size and the proportion of tumor micro-vessels less than 20μm.Conclusion:Nano-barium sulfate based SRI can achieved high definition micro vessels imaging of pancreatic cancer,and its vessel density could be quantitative analyzed.SRI has certain application value in the evaluation of pancreatic cancer angiogenesis.The study of synchrotron radiation imaging in evaluation of lymph vesselsObjectives: To investigate the application value of synchrotron radiation imaging in the evaluation of lymph vessels.Methods:The image of sulphur hexafluoride micro-bubbles solution was realized by using synchrotron radiation absorption contrast imaging(ACI)and phase contrast imaging(PCI)with pixel size of 3.7μm and the energy of 19 ke V.Absorption contrast effect was more evidence at object-detector distance of 10 mm,and on the contrary,phase contrast effect enhanced with the increase of object-detector distance.The absorption and phase contrast images of micro-bubbles were obtained and compared in vitro.In vivo study,micro-bubbles solution and iohexol were injected directly in the ICR mice subiliac lymph node respectively.ACI and PCI of lymph node and lymph vessel were obtained and compared in vivo.Results: A bright line under the tube wall induced by micro-bubbles could be clearly seen in PCI and this phenomenon could not be observed in ACI.In vivo PCI,micro-bubbles diffused in the lymph node and lymph vessel and had a well contrast with the peripheral tissue,but the lymph vessel wasn’t displayed entirely.The size distribution of micro-bubbles ranged from10 to 120μm,the majority were 20~30μm in diameter.Some micro-bubbles stuck in the lymph node and vessel 1 hour after injection.ACI could reveal lymph node and lymph vessel by iohexol lymph node injection.It was suitable for the entire lymph vessel imaging,but with significant contrast washout rate.Conclusion: Micro-bubbles based PCI can improve the contrast between lymph vessel and soft tissue and achieve a clear lymph vessel imaging.PCI and ACI have potential application value for the evaluation of lymph vessels.Application study of synchrotron radiation phase contrast imaging in radiofrequency ablation for pancreatic cancerObjectives: To investigate the reliability and application value of synchrotron radiation phase contrast imaging in the evaluation of radiofrequency ablation zone for pancreatic cancer.Methods:In vitro study,radiofrequency ablations(RFA)were applied on porcine muscle using uni-polar electrode and multi-tined electrode.In vivo study,xerograph pancreatic cancer model was established via implantation of the fragment of human pancreatic cell line Bx PC-3 into BABL/c nude mouse.RFA were applied on xerograph pancreatic cancer using electrode catheter.The RFA zone were real-time monitored by synchrotron radiation phase contrast imaging(PCI)with object-detector distance of 10 mm,pixel size of 9μm and the energy of 22 ke V.The histology analysis was performed after RFA.Results: Micro-bubbles in the RFA zone were revealed when the target region temperature reached 50 ~ 60 ℃,and this phenomenon could be clearly observed by PCI.The micro-bubbles firstly appeared at the edge of RFA electrode and radially extended outwards.At the early stage of RFA,the temperature and the range of RFA zone increased rapidly.When the temperature reached the target setting,the range of RFA zone enlarged continuously in 120~180 seconds.The duration of rapid enlargement period were different according to the electrode type,from 40 seconds to 240 seconds for uni-polar electrode,from 60 seconds to180 seconds for multi-tined electrode.The micro-bubbles zone revealed by PCI corresponded well with the RFA zone,which included the complete ablation zone and the junctional zone.Conclusion: PCI could reveal the micro-bubbles formation during the RFA,the range of which corresponded well with the exact RFA zone.PCI have potential application value for RFA zone real-time monitoring.