{"title":"鼻窦肿瘤螺旋断层治疗中场宽变化的剂量学评价:对高危器官保留、治疗效率和设置误差敏感性的影响","authors":"Supratik Sen , Sandeep Singh , Abhay Kumar Singh , Dipesh , Manindra Bhushan , Mahipal , Sarthak Tandon , Munish Gairola","doi":"10.1016/j.radphyschem.2025.113338","DOIUrl":null,"url":null,"abstract":"<div><h3>Aim</h3><div>To evaluate the dosimetric impact of varying field widths (1 cm, 2.5 cm, and 5 cm) in Helical Tomotherapy (HT) for sinonasal tumours, focusing on target coverage, organ-at-risk (OAR) sparing, treatment efficiency, and robustness against setup errors.</div></div><div><h3>Materials and methods</h3><div>This retrospective study included 497 patients with sinonasal malignancies treated using HT. Three plans per patient were generated using field widths of 1 cm, 2.5 cm, and 5 cm. Dosimetric parameters including D95 %, D98 %, D2 %, homogeneity index (HI), Paddick's conformity index (PCI), low-dose spillage (V10–V90), and Beam-on time (BOT) were evaluated. OARs assessed included optic nerves, chiasm, brainstem, lenses, and cochlea. Statistical analysis was performed using paired t-tests (p < 0.05). Setup robustness was evaluated using an anthropomorphic phantom and optically stimulated luminescent dosimeters (OSLDs) under controlled displacements (0–5 mm).</div></div><div><h3>Results</h3><div>The 1 cm field width demonstrated superior PTV conformity (PCI: 0.82), better homogeneity, and reduced OAR doses, especially to the optic structures and brainstem. BOT was significantly higher with 1 cm (286 s) but remained clinically acceptable. Wider fields (5 cm) reduced BOT but increased dose spillage and OAR exposure. Phantom analysis showed higher dose sensitivity to setup shifts in 1 cm fields but within tolerable limits.</div></div><div><h3>Conclusion</h3><div>The 1 cm field width in HT provides optimal dosimetric benefits for sinonasal tumours, improving conformity and sparing critical structures despite a modest increase in treatment time. Personalized field width selection remains essential to balance treatment quality with efficiency.</div></div>","PeriodicalId":20861,"journal":{"name":"Radiation Physics and Chemistry","volume":"239 ","pages":"Article 113338"},"PeriodicalIF":2.8000,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Dosimetric evaluation of field width variation in helical Tomotherapy for sinonasal tumours: Implications for organ-at-risk sparing, treatment efficiency, and setup error sensitivity\",\"authors\":\"Supratik Sen , Sandeep Singh , Abhay Kumar Singh , Dipesh , Manindra Bhushan , Mahipal , Sarthak Tandon , Munish Gairola\",\"doi\":\"10.1016/j.radphyschem.2025.113338\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><h3>Aim</h3><div>To evaluate the dosimetric impact of varying field widths (1 cm, 2.5 cm, and 5 cm) in Helical Tomotherapy (HT) for sinonasal tumours, focusing on target coverage, organ-at-risk (OAR) sparing, treatment efficiency, and robustness against setup errors.</div></div><div><h3>Materials and methods</h3><div>This retrospective study included 497 patients with sinonasal malignancies treated using HT. Three plans per patient were generated using field widths of 1 cm, 2.5 cm, and 5 cm. Dosimetric parameters including D95 %, D98 %, D2 %, homogeneity index (HI), Paddick's conformity index (PCI), low-dose spillage (V10–V90), and Beam-on time (BOT) were evaluated. OARs assessed included optic nerves, chiasm, brainstem, lenses, and cochlea. Statistical analysis was performed using paired t-tests (p < 0.05). Setup robustness was evaluated using an anthropomorphic phantom and optically stimulated luminescent dosimeters (OSLDs) under controlled displacements (0–5 mm).</div></div><div><h3>Results</h3><div>The 1 cm field width demonstrated superior PTV conformity (PCI: 0.82), better homogeneity, and reduced OAR doses, especially to the optic structures and brainstem. BOT was significantly higher with 1 cm (286 s) but remained clinically acceptable. Wider fields (5 cm) reduced BOT but increased dose spillage and OAR exposure. Phantom analysis showed higher dose sensitivity to setup shifts in 1 cm fields but within tolerable limits.</div></div><div><h3>Conclusion</h3><div>The 1 cm field width in HT provides optimal dosimetric benefits for sinonasal tumours, improving conformity and sparing critical structures despite a modest increase in treatment time. Personalized field width selection remains essential to balance treatment quality with efficiency.</div></div>\",\"PeriodicalId\":20861,\"journal\":{\"name\":\"Radiation Physics and Chemistry\",\"volume\":\"239 \",\"pages\":\"Article 113338\"},\"PeriodicalIF\":2.8000,\"publicationDate\":\"2025-09-26\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Radiation Physics and Chemistry\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0969806X25008308\",\"RegionNum\":3,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Radiation Physics and Chemistry","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0969806X25008308","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Dosimetric evaluation of field width variation in helical Tomotherapy for sinonasal tumours: Implications for organ-at-risk sparing, treatment efficiency, and setup error sensitivity
Aim
To evaluate the dosimetric impact of varying field widths (1 cm, 2.5 cm, and 5 cm) in Helical Tomotherapy (HT) for sinonasal tumours, focusing on target coverage, organ-at-risk (OAR) sparing, treatment efficiency, and robustness against setup errors.
Materials and methods
This retrospective study included 497 patients with sinonasal malignancies treated using HT. Three plans per patient were generated using field widths of 1 cm, 2.5 cm, and 5 cm. Dosimetric parameters including D95 %, D98 %, D2 %, homogeneity index (HI), Paddick's conformity index (PCI), low-dose spillage (V10–V90), and Beam-on time (BOT) were evaluated. OARs assessed included optic nerves, chiasm, brainstem, lenses, and cochlea. Statistical analysis was performed using paired t-tests (p < 0.05). Setup robustness was evaluated using an anthropomorphic phantom and optically stimulated luminescent dosimeters (OSLDs) under controlled displacements (0–5 mm).
Results
The 1 cm field width demonstrated superior PTV conformity (PCI: 0.82), better homogeneity, and reduced OAR doses, especially to the optic structures and brainstem. BOT was significantly higher with 1 cm (286 s) but remained clinically acceptable. Wider fields (5 cm) reduced BOT but increased dose spillage and OAR exposure. Phantom analysis showed higher dose sensitivity to setup shifts in 1 cm fields but within tolerable limits.
Conclusion
The 1 cm field width in HT provides optimal dosimetric benefits for sinonasal tumours, improving conformity and sparing critical structures despite a modest increase in treatment time. Personalized field width selection remains essential to balance treatment quality with efficiency.
期刊介绍:
Radiation Physics and Chemistry is a multidisciplinary journal that provides a medium for publication of substantial and original papers, reviews, and short communications which focus on research and developments involving ionizing radiation in radiation physics, radiation chemistry and radiation processing.
The journal aims to publish papers with significance to an international audience, containing substantial novelty and scientific impact. The Editors reserve the rights to reject, with or without external review, papers that do not meet these criteria. This could include papers that are very similar to previous publications, only with changed target substrates, employed materials, analyzed sites and experimental methods, report results without presenting new insights and/or hypothesis testing, or do not focus on the radiation effects.