Imagerie protonique pour la protonthérapie : état de l’art

More than half a century ago, Robert Wilson [1] recognized that charged particles held an intrinsic potential advantage for cancer therapy, compared with gamma rays and x-rays, and that accelerators capable of accelerating protons or heavier ions to sufficiently high energy would soon be readily available. Since the specific ionization (energy loss per unit distance) of non-relativistic ions varies nearly inversely with the kinetic energy, the radiological dose is greatest near the end of the ion path, in the 'Bragg Peak', named in honor of William Henry Bragg, who discovered the effect in 1903 [2]. Wilson proposed that with sufficient knowledge of the specific ioniz ation, or 'proton stopping power', of the tissue between skin and tumor, the ion energy could be tuned such that the ions stop in the tumor, resulting in minimal dose proximal to the tumor and nearly zero dose distal to the tumor. See figure 1 for a comparison of charged-particle irradiation with x-ray or gamma irradiation, for which the depth of the ionizing interactions cannot be controlled. In the figure, the broad flat proton dose distribution in the tumor region is realized

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“…Recent reviews of proton radiography and computed tomography also exist. For example, see [41], [42], and [43].…”

Section: Physics and Technology Of Particle Detection For Proton Imagingmentioning

confidence: 99%

Review of medical radiography and tomography with proton beams

2017

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“…X-ray medical imaging has undergone tremendous technological advances for the diagnosis and treatment of a breadth of examinations and procedures [1]. In particular, due to its rich and robust image information and shorter examination time [2][3][4][5], conebeam computed tomography (CBCT) has become standard in recent clinical applications as adaptive radiotherapy treatment [6], image-guided radiation therapy (IGRT) [6][7][8][9][10][11][12], maxillofacial applications [13][14][15], cone-beam breast tomography (CBBCT) [16][17][18][19][20][21][22][23], or proton computed tomography for particle therapy [24][25][26][27][28]. CBCT is a new technology using a cone-shaped beam and a detector that rotate 360 • around the patient, able to acquire projected data in a single rotation [29].…”

Section: Introductionmentioning

confidence: 99%

Dose Estimation by Geant4-Based Simulations for Cone-Beam CT Applications: A Systematic Review

et al. 2021

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The last two decades have witnessed increasing use of X-ray imaging and, hence, the exposure of humans to potentially harmful ionizing radiation. Computed tomography accounts for the largest portion of medically-related X-ray exposure. Accurate knowledge of ionizing radiation dose from Cone-Beam CT (CBCT) imaging is of great importance to estimate radiation risks and justification of imaging exposures. This work aimed to review the published evidence on CBCT dose estimation by focusing on studies that employ Geant4-based toolkits to estimate radiation dosage. A systematic review based on a scientometrics approach was conducted retrospectively, from January 2021, for a comprehensive overview of the trend, thematic focus, and scientific production in this topic. The search was conducted using WOS, PubMed, and Scopus databases, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. In total, 93 unique papers were found, of which only 34 met the inclusion criteria. We opine that the findings of this study provides a basis to develop accurate simulations of CBCT equipment for optimizing the trade-off between clinical benefit and radiation risk.

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