Ai-Xin Zhang, Yuhang He, Ling-An Wu, Li-Ming Chen, B. Wang
The use of x-ray imaging in medicine and other research is well known. Generally, the image quality is proportional to the total flux, but high photon energy could severely damage the specimen, so how to decrease the radiation dose while maintaining image quality is a fundamental problem. In "ghost" imaging, an image is retrieved from a known patterned illumination field and the total intensity transmitted through the object collected by a bucket detector. Using a table-top x-ray source we have realized ghost imaging of plane and natural objects with ultra-low radiation on the order of single photons. Compared with conventional x-ray imaging, a higher contrast-to-noise ratio is obtained for the same radiation dose. This new technique could greatly reduce radiation damage of biological specimens.
{"title":"Table-top X-ray Ghost Imaging with Ultra-Low Radiation","authors":"Ai-Xin Zhang, Yuhang He, Ling-An Wu, Li-Ming Chen, B. Wang","doi":"10.1364/OPTICA.5.000374","DOIUrl":"https://doi.org/10.1364/OPTICA.5.000374","url":null,"abstract":"The use of x-ray imaging in medicine and other research is well known. Generally, the image quality is proportional to the total flux, but high photon energy could severely damage the specimen, so how to decrease the radiation dose while maintaining image quality is a fundamental problem. In \"ghost\" imaging, an image is retrieved from a known patterned illumination field and the total intensity transmitted through the object collected by a bucket detector. Using a table-top x-ray source we have realized ghost imaging of plane and natural objects with ultra-low radiation on the order of single photons. Compared with conventional x-ray imaging, a higher contrast-to-noise ratio is obtained for the same radiation dose. This new technique could greatly reduce radiation damage of biological specimens.","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76428726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.1007/978-981-10-4086-3_102
J. D'iaz, Octavio Andr'es Gonz'alez-Estrada, C. L'opez
{"title":"Biomechanical analysis of a cranial Patient Specific Implant on the interface with the bone using the Finite Element Method","authors":"J. D'iaz, Octavio Andr'es Gonz'alez-Estrada, C. L'opez","doi":"10.1007/978-981-10-4086-3_102","DOIUrl":"https://doi.org/10.1007/978-981-10-4086-3_102","url":null,"abstract":"","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"133 1","pages":"405-408"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89224232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-06-22DOI: 10.23730/CYRSP-2017-001.309
M. Grossmann
This contribution describes general concepts for control and safety systems in proton therapy. These concepts are illustrated by concrete examples implemented in the Proscan facility at PSI.
{"title":"Therapy Control and Patient Safety for Proton Therapy","authors":"M. Grossmann","doi":"10.23730/CYRSP-2017-001.309","DOIUrl":"https://doi.org/10.23730/CYRSP-2017-001.309","url":null,"abstract":"This contribution describes general concepts for control and safety systems in proton therapy. These concepts are illustrated by concrete examples implemented in the Proscan facility at PSI.","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"71 1","pages":"309-309"},"PeriodicalIF":0.0,"publicationDate":"2017-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72790514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-06-22DOI: 10.23730/CYRSP-2017-001.285
D. Meer
The medical commissioning is an important step to bring a particle gantry into clinical operation for tumour treatments. This involves the parametrization and characterization of all relevant systems including the beam delivery, the patient table, the imaging systems and the connection to all required software components. This article is limited to necessary tasks for the beam delivery system of a pencil beam scanning system. Usually the commissioning starts with the characterization of the unscanned beam and the calibration of the beam energy. The following steps are the parametrization of the scanning system, the commissioning of the beam position monitoring system and characterization of the spot size, all requiring precisions better than 1 mm. The commissioning effort for these tasks depends also on the gantry topology. Finally, the calibration of the dose measurement system ensures that any dose distribution can be delivered with an absolute precision better than 1%.
{"title":"Medical Physics Commissioning","authors":"D. Meer","doi":"10.23730/CYRSP-2017-001.285","DOIUrl":"https://doi.org/10.23730/CYRSP-2017-001.285","url":null,"abstract":"The medical commissioning is an important step to bring a particle gantry into clinical operation for tumour treatments. This involves the parametrization and characterization of all relevant systems including the beam delivery, the patient table, the imaging systems and the connection to all required software components. This article is limited to necessary tasks for the beam delivery system of a pencil beam scanning system. Usually the commissioning starts with the characterization of the unscanned beam and the calibration of the beam energy. The following steps are the parametrization of the scanning system, the commissioning of the beam position monitoring system and characterization of the spot size, all requiring precisions better than 1 mm. The commissioning effort for these tasks depends also on the gantry topology. Finally, the calibration of the dose measurement system ensures that any dose distribution can be delivered with an absolute precision better than 1%.","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73174450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-06-22DOI: 10.23730/CYRSP-2017-001.177
S. Zaremba, W. Kleeven
Classical, isochronous, and synchro-cyclotrons are introduced. Transverse and longitudinal beam dynamics in these accelerators are covered. The problem of vertical focusing and iscochronism in compact isochronous cyclotrons is treated in some detail. Different methods for isochronization of the cyclotron magnetic field are discussed. The limits of the classical cyclotron are explained. Typical features of the synchro-cyclotron, such as the beam capture problem, stable phase motion, and the extraction problem are discussed. The main design goals for beam injection are explained and special problems related to a central region with an internal ion source are considered. The principle of a Penning ion gauge source is addressed. The issue of vertical focusing in the cyclotron centre is briefly discussed. Several examples of numerical simulations are given. Different methods of (axial) injection are briefly outlined. Different solutions for beam extraction are described. These include the internal target, extraction by stripping, resonant extraction using a deflector, regenerative extraction, and self-extraction. Different methods of creating a turn separation are explained. Different types of extraction device, such as harmonic coils, deflectors, and gradient corrector channels, are outlined. Some general considerations for cyclotron magnetic design are given and the use of modern magnetic modelling tools is discussed, with a few illustrative examples. An approach is chosen where the accent is less on completeness and rigorousness (because this has already been done) and more on explaining and illustrating the main principles that are used in medical cyclotrons. Sometimes a more industrial viewpoint is taken. The use of complicated formulae is limited.
{"title":"Cyclotrons: Magnetic Design and Beam Dynamics","authors":"S. Zaremba, W. Kleeven","doi":"10.23730/CYRSP-2017-001.177","DOIUrl":"https://doi.org/10.23730/CYRSP-2017-001.177","url":null,"abstract":"Classical, isochronous, and synchro-cyclotrons are introduced. Transverse and longitudinal beam dynamics in these accelerators are covered. The problem of vertical focusing and iscochronism in compact isochronous cyclotrons is treated in some detail. Different methods for isochronization of the cyclotron magnetic field are discussed. The limits of the classical cyclotron are explained. Typical features of the synchro-cyclotron, such as the beam capture problem, stable phase motion, and the extraction problem are discussed. The main design goals for beam injection are explained and special problems related to a central region with an internal ion source are considered. The principle of a Penning ion gauge source is addressed. The issue of vertical focusing in the cyclotron centre is briefly discussed. Several examples of numerical simulations are given. Different methods of (axial) injection are briefly outlined. Different solutions for beam extraction are described. These include the internal target, extraction by stripping, resonant extraction using a deflector, regenerative extraction, and self-extraction. Different methods of creating a turn separation are explained. Different types of extraction device, such as harmonic coils, deflectors, and gradient corrector channels, are outlined. Some general considerations for cyclotron magnetic design are given and the use of modern magnetic modelling tools is discussed, with a few illustrative examples. An approach is chosen where the accent is less on completeness and rigorousness (because this has already been done) and more on explaining and illustrating the main principles that are used in medical cyclotrons. Sometimes a more industrial viewpoint is taken. The use of complicated formulae is limited.","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90390827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-06-22DOI: 10.23730/CYRSP-2017-001.241
J. Schippers
The beam transport system between accelerator and patient treatment location in a particle therapy facility is described. After some general layout aspects the major beam handling tasks of this system are discussed. These are energy selection, an optimal transport of the particle beam to the beam delivery device and the gantry, a device that is able to rotate a beam delivery system around the patient, so that the tumour can be irradiated from almost any direction. Also the method of pencil beam scanning is described and how this is implemented within a gantry. Using this method the particle dose is spread over the tumour volume to the prescribed dose distribution.
{"title":"Beam Transport Systems for Particle Therapy.","authors":"J. Schippers","doi":"10.23730/CYRSP-2017-001.241","DOIUrl":"https://doi.org/10.23730/CYRSP-2017-001.241","url":null,"abstract":"The beam transport system between accelerator and patient treatment location in a particle therapy facility is described. After some general layout aspects the major beam handling tasks of this system are discussed. These are energy selection, an optimal transport of the particle beam to the beam delivery device and the gantry, a device that is able to rotate a beam delivery system around the patient, so that the tumour can be irradiated from almost any direction. Also the method of pencil beam scanning is described and how this is implemented within a gantry. Using this method the particle dose is spread over the tumour volume to the prescribed dose distribution.","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79675987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-06-22DOI: 10.23730/CYRSP-2017-001.71
K. Parodi
With the continued evolution of modern radiation therapy towards high precision delivery of high therapeutic doses to the tumour while optimally sparing surrounding healthy tissue, imaging becomes a crucial component to identify the intended target, properly position it at the treatment site and, in more advanced research applications, visualize the treatment delivery. This contribution reviews the main role of imaging in modern external beam radiation therapy, with special emphasis on emerging ion beam therapy techniques, which aim at exploiting the favourable properties of ion interaction in matter for unprecedented ballistic accuracy in dose delivery
{"title":"Imaging in Radiotherapy.","authors":"K. Parodi","doi":"10.23730/CYRSP-2017-001.71","DOIUrl":"https://doi.org/10.23730/CYRSP-2017-001.71","url":null,"abstract":"With the continued evolution of modern radiation therapy towards high precision delivery of high therapeutic doses to the tumour while optimally sparing surrounding healthy tissue, imaging becomes a crucial component to identify the intended target, properly position it at the treatment site and, in more advanced research applications, visualize the treatment delivery. This contribution reviews the main role of imaging in modern external beam radiation therapy, with special emphasis on emerging ion beam therapy techniques, which aim at exploiting the favourable properties of ion interaction in matter for unprecedented ballistic accuracy in dose delivery","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72698397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-06-22DOI: 10.23730/CYRSP-2017-001.165
J. Schippers
In particle therapy with protons a cyclotron is one of the most used particle accelerators. Here it will be explained how a cyclotron works, some beam dynamics aspects, its major subsystems, as well as the advantages and disadvantages of a cyclotron for this application are discussed. The difference between the standard isochronous cyclotron and the synchrocyclotron is explained. New developments are presented and especially those which aim to reduce the size of the accelerator.
{"title":"Cyclotrons for Particle Therapy.","authors":"J. Schippers","doi":"10.23730/CYRSP-2017-001.165","DOIUrl":"https://doi.org/10.23730/CYRSP-2017-001.165","url":null,"abstract":"In particle therapy with protons a cyclotron is one of the most used particle accelerators. Here it will be explained how a cyclotron works, some beam dynamics aspects, its major subsystems, as well as the advantages and disadvantages of a cyclotron for this application are discussed. The difference between the standard isochronous cyclotron and the synchrocyclotron is explained. New developments are presented and especially those which aim to reduce the size of the accelerator.","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"185 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88337253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-06-22DOI: 10.23730/CYRSP-2017-001.49
S. Safai
This paper focuses on some dosimetry aspects of proton therapy and pencil beam scanning based on the experience accumulated at Paul Scherrer Institute(PSI). The basic formalism for absolute dosimetry in proton therapy is outlined and the two main techniques and equipment to perform the primary beam monitor chamber calibration are presented. Depth-dose curve and lateral beam width measurements are exposed and discussed in detail, with particular attention to the size of the ionization chamber and the characteristic of scintillating-CCD dosimetry systems, respectively. It is also explained how the angular-spatial distribution of individual pencil beams can be determined in practice. The equipment and the techniques for performing regularmachine-specific quality checks are focused on (i)output constancy checks, (ii)pencil beam position and size checks and (iii)beam energy checks. Finally, patient-specific verification is addressed.
{"title":"Dose Delivery Verification","authors":"S. Safai","doi":"10.23730/CYRSP-2017-001.49","DOIUrl":"https://doi.org/10.23730/CYRSP-2017-001.49","url":null,"abstract":"This paper focuses on some dosimetry aspects of proton therapy and pencil beam scanning based on the experience accumulated at Paul Scherrer Institute(PSI). The basic formalism for absolute dosimetry in proton therapy is outlined and the two main techniques and equipment to perform the primary beam monitor chamber calibration are presented. Depth-dose curve and lateral beam width measurements are exposed and discussed in detail, with particular attention to the size of the ionization chamber and the characteristic of scintillating-CCD dosimetry systems, respectively. It is also explained how the angular-spatial distribution of individual pencil beams can be determined in practice. The equipment and the techniques for performing regularmachine-specific quality checks are focused on (i)output constancy checks, (ii)pencil beam position and size checks and (iii)beam energy checks. Finally, patient-specific verification is addressed.","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"11 1","pages":"49"},"PeriodicalIF":0.0,"publicationDate":"2017-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78702969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-06-22DOI: 10.23730/CYRSP-2017-001.13
S. Giordanengo, M. Donetti
Radiation therapy aims to deliver the prescribed amount of dose to a tumour at the same time as sparing the surrounding tissues as much as possible. In charged particle therapy, delivering the prescribed dose is equivalent to delivering the prescribed number of ions of a given energy at each position of the irradiation field. The accurate delivery is committed to a dose delivery (DD) system that shapes, guides and controls the beam before the patient entrance. Most of the early DD systems provided uniform lateral dose profiles by using different devices, mainly patient-specific, placed in the beam line to shape the three-dimensional final target dose. More recently, systems that provide highly conformal dose distributions using thousands of narrow beams at well-defined energy were developed which feature advanced scanning magnets and real-time beam monitors, without patient-specific hardware. This lecture will cover the general dose delivery concept as well as the different DD instrumentations depending mainly on the beam delivery technique and on the particle and accelerator types. Some characteristic worldwide DD and beam monitor systems will be mentioned.
{"title":"arXiv : Dose Delivery Concept and Instrumentation","authors":"S. Giordanengo, M. Donetti","doi":"10.23730/CYRSP-2017-001.13","DOIUrl":"https://doi.org/10.23730/CYRSP-2017-001.13","url":null,"abstract":"Radiation therapy aims to deliver the prescribed amount of dose to a tumour at the same time as sparing the surrounding tissues as much as possible. In charged particle therapy, delivering the prescribed dose is equivalent to delivering the prescribed number of ions of a given energy at each position of the irradiation field. The accurate delivery is committed to a dose delivery (DD) system that shapes, guides and controls the beam before the patient entrance. Most of the early DD systems provided uniform lateral dose profiles by using different devices, mainly patient-specific, placed in the beam line to shape the three-dimensional final target dose. More recently, systems that provide highly conformal dose distributions using thousands of narrow beams at well-defined energy were developed which feature advanced scanning magnets and real-time beam monitors, without patient-specific hardware. This lecture will cover the general dose delivery concept as well as the different DD instrumentations depending mainly on the beam delivery technique and on the particle and accelerator types. Some characteristic worldwide DD and beam monitor systems will be mentioned.","PeriodicalId":8462,"journal":{"name":"arXiv: Medical Physics","volume":"28 1","pages":"13-47"},"PeriodicalIF":0.0,"publicationDate":"2017-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85047567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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