In recent years,multi-photon 3D laser printing has become a widely used tool for the fabrication of micro-and nanostructures for a large variety of applications.Typically,thorough sample characterisation is key for an...In recent years,multi-photon 3D laser printing has become a widely used tool for the fabrication of micro-and nanostructures for a large variety of applications.Typically,thorough sample characterisation is key for an efficient optimisation of the printing process.To date,three-dimensional microscopic inspection has usually been carried out on finished 3D printed microstructures,that is,using ex-situ approaches.In contrast,in-situ 3D characterization tools are desirable for quickly assessing the quality and properties of 3D printed microstructures.Along these lines,we present and characterise a Fourier-domain optical coherence tomography(FD-OCT)system that can be readily integrated into an existing 3D laser lithography setup.We demonstrate its capabilities by examining different 3D printed polymer microstructures immersed in a liquid photoresist.In such samples,local reflectivity arises from the(refractive-index)contrasts between the polymerised and non-polymerised regions.Thus,the refractive index of the printed material can be extracted.Furthermore,we demonstrate that the reflectivity of polymer-monomer transitions exhibits time-dependent behaviour after printing.Supported by transfer-matrix calculations,we explain this effect in terms of the time-dependent graded-index transition originating from monomer diffusion into the polymer matrix.Finally,we show exemplary 3D reconstructions of printed structures that can be readily compared with 3D computer designs.展开更多
Immobilization devices may be a valuable aid to ensure the improved effectiveness of radiotherapy treatments where constraining the movements of specific anatomical segments is crucial. This need is also present in ot...Immobilization devices may be a valuable aid to ensure the improved effectiveness of radiotherapy treatments where constraining the movements of specific anatomical segments is crucial. This need is also present in other situations, specifically when the superposition of various medical images is required for fine identification and characterization of some pathologies. Because of their structural characteristics, existing head immobilization systems may be claustrophobic and very uncomfortable for patients, during both the modeling and usage stages. Because of this, it is important to minimize all the discomforts related to the mask to alleviate patients’ distress and to simultaneously guarantee and maximize the restraint effectiveness of the mask. In the present work, various head immobilization mask models are proposed based on geometrical information extracted from computerized tomography images and from 3D laser scanning point clouds. These models also consider the corresponding connection to a radiotherapy table, as this connection is easily altered to accommodate various manufacturers’ solutions. A set of materials used in the radiotherapy field is considered to allow the assessment of the stiffness and strength of the masks when submitted to typical loadings.展开更多
Objective: To investigate the successful rate and accuracy of percutaneous radiofrequency thermocoagulation (PRT) for treatment of primary trigeminal neuralgia (PTN) with customized navigated template via three dimens...Objective: To investigate the successful rate and accuracy of percutaneous radiofrequency thermocoagulation (PRT) for treatment of primary trigeminal neuralgia (PTN) with customized navigated template via three dimensional (3D) printing technique. Methods: 65 patients with PTN were recruited from January 2014 to March 2015 and randomly divided into two groups: template group (n = 28) and traditional group (n = 37). The patients in traditional group received PRT under guidance of C-arm fluoroscopy, while the ones in template group were treated with customized navigated templates. The data of time, depth and accuracy rate of puncture, the average effective dose equivalent of radiation, complications after operation were collected and analyzed. Results: No intra-operative failures occurred in the template group: the pain was alleviated immediately after operation. Accuracy rate of the template group was 100% while 96% was achieved in traditional group. However, the average time of puncture by the template was significantly reduced compared with traditional group (2.37 ± 0.64 minutes and 24.2 ± 6.55 minutes, respectively;P 0.05). No complications were observed in template group while several complications such as blooding, leakage of cerebrospinal fluid and dizziness were observed in traditional group. Conclusion: The application of customized template is advocated for improving the accuracy of PRT.展开更多
Objective To analyze the difference of dosimetric parameters between pre-plan and post-plan of 125I radioactive seed implantation assisted by 3D printing individual non-coplanar template（3D printing template）for loc...Objective To analyze the difference of dosimetric parameters between pre-plan and post-plan of 125I radioactive seed implantation assisted by 3D printing individual non-coplanar template（3D printing template）for locally recurrent rectal cancer（LRRC）.Methods From February 2016 to April 2016,a total of 10 patients with locally recurrent rectal cancer received 125I seeds implan-展开更多
The objective of this research was to explore the feasibility and clinical application of a new diagnostic imaging method for the diagnosis and treatment of iliac vein compression(IVC)based on three-dimensional(3D)dig...The objective of this research was to explore the feasibility and clinical application of a new diagnostic imaging method for the diagnosis and treatment of iliac vein compression(IVC)based on three-dimensional(3D)digital reconstruction and printing.This study included patients with chronic venous disease(CVD)who were admitted to the Department of Vascular Surgery,Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine,from January to March,2019,and underwent computed tomography venography(CTV)to detect IVC.CTV findings were used to reconstruct 3D-printed models of blood vessels.A total of 17 patients(5 men and 12 women)with IVC,who were primarily diagnosed with CTV,were included in this study.In addition,24 significant venous compression sites were found in 17 patients,of which 7 patients had only one compression site(41.2%),nine patients had two compression sites(52.9%),and one patient had three compression sites(5.9%).3D digital reconstruction and printing is a convenient,noninvasive,and accurate diagnostic imaging method that provides a clear and accurate evaluation of veins and arteries,as well as the anatomical positional relationship for the diagnosis and treatment of IVC.展开更多
We are in the midst of exciting advancements in new technologies and innovative research in precision medicine.Among these,3D printing is one of the most frequently seen in clinical orthopaedic settings.This new techn...We are in the midst of exciting advancements in new technologies and innovative research in precision medicine.Among these,3D printing is one of the most frequently seen in clinical orthopaedic settings.This new technique has been adopted in a vast range of applications in spine surgery,such as producing anatomical models,surgical templates,preoperative plans,and spinal implants.Some studies on 3D printing technologies in spine surgery have reported the benefits of this emerging technology with more effective manufacturing,more visualisation for communication,and more precise navigation for screw insertion and osteotomy.In addition,in customised implant design and fabrication processes,3D printing products with anatomical adaptions and complex porous microstructure show some attractive advantages in terms of fit and osteoinductivity.However,there are still some concerns about the safety and feasibility of the application of 3D printing technology in spine surgery.We review the literature on and share our experiences with the application of 3D printing from the beginning of collaborations between doctors and computer-aided design(CAD)designers to the final follow-up of clinical patients.展开更多
提出一种基于微波干涉电路的液体介电常数测量方法。首先,采用接地共面波导(Grounded Coplanar Waveguide,CPWG)作为敏感元件,运用传输线法测量加载不同待测材料(Material Under Test,MUT)情况下损耗和相位的变化量。然后,使用干涉电路...提出一种基于微波干涉电路的液体介电常数测量方法。首先,采用接地共面波导(Grounded Coplanar Waveguide,CPWG)作为敏感元件,运用传输线法测量加载不同待测材料(Material Under Test,MUT)情况下损耗和相位的变化量。然后,使用干涉电路将MUT引起的幅度和相位变化映射为混频器输出的直流电压值,摆脱了对矢量网络分析仪等大型测试设备的依赖。最后,通过仿真以及多种有损耗液体实物测试验证了所提测量方法的有效性,测量结果显示,传感器对于介电常数实部虚部的提取误差小于3%,具有很好的实用价值。展开更多
基金This work was funded by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany’s Excellence Strategy 2082/1-390761711(Excellence Cluster“3D Matter Made to Order”).
文摘In recent years,multi-photon 3D laser printing has become a widely used tool for the fabrication of micro-and nanostructures for a large variety of applications.Typically,thorough sample characterisation is key for an efficient optimisation of the printing process.To date,three-dimensional microscopic inspection has usually been carried out on finished 3D printed microstructures,that is,using ex-situ approaches.In contrast,in-situ 3D characterization tools are desirable for quickly assessing the quality and properties of 3D printed microstructures.Along these lines,we present and characterise a Fourier-domain optical coherence tomography(FD-OCT)system that can be readily integrated into an existing 3D laser lithography setup.We demonstrate its capabilities by examining different 3D printed polymer microstructures immersed in a liquid photoresist.In such samples,local reflectivity arises from the(refractive-index)contrasts between the polymerised and non-polymerised regions.Thus,the refractive index of the printed material can be extracted.Furthermore,we demonstrate that the reflectivity of polymer-monomer transitions exhibits time-dependent behaviour after printing.Supported by transfer-matrix calculations,we explain this effect in terms of the time-dependent graded-index transition originating from monomer diffusion into the polymer matrix.Finally,we show exemplary 3D reconstructions of printed structures that can be readily compared with 3D computer designs.
基金supported by the Project IPL/2016/Soft Imob/ISEL and Project LAETA—UID/EMS/50022/2019
文摘Immobilization devices may be a valuable aid to ensure the improved effectiveness of radiotherapy treatments where constraining the movements of specific anatomical segments is crucial. This need is also present in other situations, specifically when the superposition of various medical images is required for fine identification and characterization of some pathologies. Because of their structural characteristics, existing head immobilization systems may be claustrophobic and very uncomfortable for patients, during both the modeling and usage stages. Because of this, it is important to minimize all the discomforts related to the mask to alleviate patients’ distress and to simultaneously guarantee and maximize the restraint effectiveness of the mask. In the present work, various head immobilization mask models are proposed based on geometrical information extracted from computerized tomography images and from 3D laser scanning point clouds. These models also consider the corresponding connection to a radiotherapy table, as this connection is easily altered to accommodate various manufacturers’ solutions. A set of materials used in the radiotherapy field is considered to allow the assessment of the stiffness and strength of the masks when submitted to typical loadings.
文摘Objective: To investigate the successful rate and accuracy of percutaneous radiofrequency thermocoagulation (PRT) for treatment of primary trigeminal neuralgia (PTN) with customized navigated template via three dimensional (3D) printing technique. Methods: 65 patients with PTN were recruited from January 2014 to March 2015 and randomly divided into two groups: template group (n = 28) and traditional group (n = 37). The patients in traditional group received PRT under guidance of C-arm fluoroscopy, while the ones in template group were treated with customized navigated templates. The data of time, depth and accuracy rate of puncture, the average effective dose equivalent of radiation, complications after operation were collected and analyzed. Results: No intra-operative failures occurred in the template group: the pain was alleviated immediately after operation. Accuracy rate of the template group was 100% while 96% was achieved in traditional group. However, the average time of puncture by the template was significantly reduced compared with traditional group (2.37 ± 0.64 minutes and 24.2 ± 6.55 minutes, respectively;P 0.05). No complications were observed in template group while several complications such as blooding, leakage of cerebrospinal fluid and dizziness were observed in traditional group. Conclusion: The application of customized template is advocated for improving the accuracy of PRT.
文摘Objective To analyze the difference of dosimetric parameters between pre-plan and post-plan of 125I radioactive seed implantation assisted by 3D printing individual non-coplanar template（3D printing template）for locally recurrent rectal cancer（LRRC）.Methods From February 2016 to April 2016,a total of 10 patients with locally recurrent rectal cancer received 125I seeds implan-
基金the National Natural Science Foundation of China(No.8167440)the Clinical Research Program of 9th People’s Hospital,Shanghai Jiao Tong University School of Medicine(No.JYLJ026)the Class IV Peak Subject Program of Shanghai Jiao Tong University School of Medicine(No.GXQ10)。
文摘The objective of this research was to explore the feasibility and clinical application of a new diagnostic imaging method for the diagnosis and treatment of iliac vein compression(IVC)based on three-dimensional(3D)digital reconstruction and printing.This study included patients with chronic venous disease(CVD)who were admitted to the Department of Vascular Surgery,Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine,from January to March,2019,and underwent computed tomography venography(CTV)to detect IVC.CTV findings were used to reconstruct 3D-printed models of blood vessels.A total of 17 patients(5 men and 12 women)with IVC,who were primarily diagnosed with CTV,were included in this study.In addition,24 significant venous compression sites were found in 17 patients,of which 7 patients had only one compression site(41.2%),nine patients had two compression sites(52.9%),and one patient had three compression sites(5.9%).3D digital reconstruction and printing is a convenient,noninvasive,and accurate diagnostic imaging method that provides a clear and accurate evaluation of veins and arteries,as well as the anatomical positional relationship for the diagnosis and treatment of IVC.
基金the National Key Research and Development Program of China(No.2017YFB1104104)the Special Foundation for Innovation of Science and Technology of Shanghai Jiao Tong University(Nos.GXQ201810 and GXQ202003)。
文摘We are in the midst of exciting advancements in new technologies and innovative research in precision medicine.Among these,3D printing is one of the most frequently seen in clinical orthopaedic settings.This new technique has been adopted in a vast range of applications in spine surgery,such as producing anatomical models,surgical templates,preoperative plans,and spinal implants.Some studies on 3D printing technologies in spine surgery have reported the benefits of this emerging technology with more effective manufacturing,more visualisation for communication,and more precise navigation for screw insertion and osteotomy.In addition,in customised implant design and fabrication processes,3D printing products with anatomical adaptions and complex porous microstructure show some attractive advantages in terms of fit and osteoinductivity.However,there are still some concerns about the safety and feasibility of the application of 3D printing technology in spine surgery.We review the literature on and share our experiences with the application of 3D printing from the beginning of collaborations between doctors and computer-aided design(CAD)designers to the final follow-up of clinical patients.
文摘提出一种基于微波干涉电路的液体介电常数测量方法。首先,采用接地共面波导(Grounded Coplanar Waveguide,CPWG)作为敏感元件,运用传输线法测量加载不同待测材料(Material Under Test,MUT)情况下损耗和相位的变化量。然后,使用干涉电路将MUT引起的幅度和相位变化映射为混频器输出的直流电压值,摆脱了对矢量网络分析仪等大型测试设备的依赖。最后,通过仿真以及多种有损耗液体实物测试验证了所提测量方法的有效性,测量结果显示,传感器对于介电常数实部虚部的提取误差小于3%,具有很好的实用价值。
