{"title":"Three-dimensional electron paramagnetic resonance (EPR) imaging of an X-ray-irradiated bovine tooth: A feasibility study","authors":"Yukihiro Arai , Mai Taguchi , Oki Mitarai , Ichiro Yamaguchi , Hideo Sato-Akaba , Shingo Matsumoto , Minoru Miyake , Hiroshi Hirata","doi":"10.1016/j.radmeas.2025.107381","DOIUrl":null,"url":null,"abstract":"<div><div>This study aimed to demonstrate the feasibility of three-dimensional (3D) mapping of an X-ray-irradiated bovine tooth using 750-MHz continuous-wave electron paramagnetic resonance (EPR). A bovine tooth that received 50-Gy X-ray was used as a dosimetry sample. To enhance the sensitivity of EPR detection, we used an ultra-low-noise saturated power amplifier following an RF synthesizer. Moreover, the automatic tuning control (ATC) system, which locks the frequency of the radiofrequency (RF) resonator to the RF carrier frequency, was combined with another RF frequency adjustment system for the RF synthesizer to enable long-term data acquisition over several hours. A 4-hydroxy-TEMPO radical solution was measured as a standard EPR signal source to investigate the enhancement of signal sensitivity. The radiation-induced EPR signals in tooth enamel were reconstructed using the algebraic reconstruction technique (ART). The signal-to-noise ratios achieved for the 4-hydroxy-TEMPO radical solution and a 50-Gy irradiated bovine tooth were twice as high as those obtained previously. Radiation-induced signals in the bovine tooth were mapped in 3D space for 3 h 45 min. The spatial resolution in the 3D map reached 2.1 mm. While low-field EPR was considered to be less sensitive for mapping the absorbed dose of an irradiated tooth, we demonstrated that low-field EPR at 26.8 mT (750 MHz) is applicable to the 3D mapping of 50-Gy-irradiated tooth enamel. Our findings represent a step towards a technology for absorbed-dose mapping of human teeth in cases of accidental exposure to head and neck cancer patients.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"181 ","pages":"Article 107381"},"PeriodicalIF":1.6000,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Radiation Measurements","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1350448725000101","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"NUCLEAR SCIENCE & TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
This study aimed to demonstrate the feasibility of three-dimensional (3D) mapping of an X-ray-irradiated bovine tooth using 750-MHz continuous-wave electron paramagnetic resonance (EPR). A bovine tooth that received 50-Gy X-ray was used as a dosimetry sample. To enhance the sensitivity of EPR detection, we used an ultra-low-noise saturated power amplifier following an RF synthesizer. Moreover, the automatic tuning control (ATC) system, which locks the frequency of the radiofrequency (RF) resonator to the RF carrier frequency, was combined with another RF frequency adjustment system for the RF synthesizer to enable long-term data acquisition over several hours. A 4-hydroxy-TEMPO radical solution was measured as a standard EPR signal source to investigate the enhancement of signal sensitivity. The radiation-induced EPR signals in tooth enamel were reconstructed using the algebraic reconstruction technique (ART). The signal-to-noise ratios achieved for the 4-hydroxy-TEMPO radical solution and a 50-Gy irradiated bovine tooth were twice as high as those obtained previously. Radiation-induced signals in the bovine tooth were mapped in 3D space for 3 h 45 min. The spatial resolution in the 3D map reached 2.1 mm. While low-field EPR was considered to be less sensitive for mapping the absorbed dose of an irradiated tooth, we demonstrated that low-field EPR at 26.8 mT (750 MHz) is applicable to the 3D mapping of 50-Gy-irradiated tooth enamel. Our findings represent a step towards a technology for absorbed-dose mapping of human teeth in cases of accidental exposure to head and neck cancer patients.
期刊介绍：
The journal seeks to publish papers that present advances in the following areas: spontaneous and stimulated luminescence (including scintillating materials, thermoluminescence, and optically stimulated luminescence); electron spin resonance of natural and synthetic materials; the physics, design and performance of radiation measurements (including computational modelling such as electronic transport simulations); the novel basic aspects of radiation measurement in medical physics. Studies of energy-transfer phenomena, track physics and microdosimetry are also of interest to the journal.
Applications relevant to the journal, particularly where they present novel detection techniques, novel analytical approaches or novel materials, include: personal dosimetry (including dosimetric quantities, active/electronic and passive monitoring techniques for photon, neutron and charged-particle exposures); environmental dosimetry (including methodological advances and predictive models related to radon, but generally excluding local survey results of radon where the main aim is to establish the radiation risk to populations); cosmic and high-energy radiation measurements (including dosimetry, space radiation effects, and single event upsets); dosimetry-based archaeological and Quaternary dating; dosimetry-based approaches to thermochronometry; accident and retrospective dosimetry (including activation detectors), and dosimetry and measurements related to medical applications.
京公网安备 11010802042870号
京ICP备2023020795号-1
分享
求助内容：
应助结果提醒方式：
扫码关注我们
