{"title":"空气流入真空固定装置会影响设置误差。","authors":"Fumiyasu Matsubayashi, Tatsuya Kamima, Yasushi Ito, Yasuo Yoshioka","doi":"10.1007/s12194-024-00822-w","DOIUrl":null,"url":null,"abstract":"<p><p>We aimed to determine the impact of air inflow into vacuum-type immobilization devices (VIDs) on setup errors. We assigned 70 patients undergoing radiotherapy for head and neck cancer to groups V (n = 34) or N (n = 36) according to whether the VIDs were deflated weekly or not deflated during treatment, respectively. We calculated systematic errors (Σ) as the standard deviations (SDs) of mean errors, and random errors (σ) as the root mean square of SDs in each patient. We compared overall means (μ), SDs (SD<sub>overall</sub>), random errors and systematic errors. We also measured temporary pressure changes in VIDs to determine the influence of pressure changes in VIDs on setup errors. The μ was within 0.20 mm and 0.2° in both groups, whereas SD<sub>overall</sub> significantly differed between them. The SD<sub>overall</sub> differed the most in the Roll axes of groups N (0. 87°) and V (0.58°). The Σ and σ values were lower in all axes of group V than in group N. Despite the initial deflation target of - 70 kPa, the pressure in VIDs reached - 5 kPa at the end of treatment. However, weekly deflation apparently maintained pressure at - 20 kPa. Effective pressure control in VIDs can reduce patient-by-patient variation and improve setup reproducibility for individual patients, consequently resulting in small variations among overall setup errors.</p>","PeriodicalId":46252,"journal":{"name":"Radiological Physics and Technology","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Air inflow into vacuum-type immobilization devices impacts setup errors.\",\"authors\":\"Fumiyasu Matsubayashi, Tatsuya Kamima, Yasushi Ito, Yasuo Yoshioka\",\"doi\":\"10.1007/s12194-024-00822-w\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>We aimed to determine the impact of air inflow into vacuum-type immobilization devices (VIDs) on setup errors. We assigned 70 patients undergoing radiotherapy for head and neck cancer to groups V (n = 34) or N (n = 36) according to whether the VIDs were deflated weekly or not deflated during treatment, respectively. We calculated systematic errors (Σ) as the standard deviations (SDs) of mean errors, and random errors (σ) as the root mean square of SDs in each patient. We compared overall means (μ), SDs (SD<sub>overall</sub>), random errors and systematic errors. We also measured temporary pressure changes in VIDs to determine the influence of pressure changes in VIDs on setup errors. The μ was within 0.20 mm and 0.2° in both groups, whereas SD<sub>overall</sub> significantly differed between them. The SD<sub>overall</sub> differed the most in the Roll axes of groups N (0. 87°) and V (0.58°). The Σ and σ values were lower in all axes of group V than in group N. Despite the initial deflation target of - 70 kPa, the pressure in VIDs reached - 5 kPa at the end of treatment. However, weekly deflation apparently maintained pressure at - 20 kPa. Effective pressure control in VIDs can reduce patient-by-patient variation and improve setup reproducibility for individual patients, consequently resulting in small variations among overall setup errors.</p>\",\"PeriodicalId\":46252,\"journal\":{\"name\":\"Radiological Physics and Technology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.7000,\"publicationDate\":\"2024-09-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Radiological Physics and Technology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1007/s12194-024-00822-w\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2024/6/19 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"Q3\",\"JCRName\":\"RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Radiological Physics and Technology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1007/s12194-024-00822-w","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/6/19 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING","Score":null,"Total":0}
引用次数: 0
摘要
我们的目的是确定真空固定装置(VID)中的空气流入量对设置误差的影响。我们将 70 名接受头颈部癌症放疗的患者按照 VID 每周放气或治疗期间不放气的情况分别分为 V 组(34 人)或 N 组(36 人)。我们用平均误差的标准差 (SD) 计算系统误差 (Σ),用 SD 的均方根计算随机误差 (σ)。我们比较了总体平均值 (μ)、标差 (SDoverall)、随机误差和系统误差。我们还测量了 VID 中的临时压力变化,以确定 VID 中的压力变化对设置误差的影响。两组的 μ 和 SDoverall 分别在 0.20 mm 和 0.2° 范围内,而 SDoverall 在两组之间存在显著差异。在 N 组(0.87°)和 V 组(0.58°)的滚轴上,SDoverall 的差异最大。尽管最初的放气目标值为 - 70 kPa,但在治疗结束时,VIDs 的压力达到了 - 5 kPa。然而,每周一次的放气显然能将压力维持在 - 20 kPa。有效控制 VIDs 中的压力可以减少患者之间的差异,提高个别患者设置的可重复性,从而使整体设置误差的差异很小。
Air inflow into vacuum-type immobilization devices impacts setup errors.
We aimed to determine the impact of air inflow into vacuum-type immobilization devices (VIDs) on setup errors. We assigned 70 patients undergoing radiotherapy for head and neck cancer to groups V (n = 34) or N (n = 36) according to whether the VIDs were deflated weekly or not deflated during treatment, respectively. We calculated systematic errors (Σ) as the standard deviations (SDs) of mean errors, and random errors (σ) as the root mean square of SDs in each patient. We compared overall means (μ), SDs (SDoverall), random errors and systematic errors. We also measured temporary pressure changes in VIDs to determine the influence of pressure changes in VIDs on setup errors. The μ was within 0.20 mm and 0.2° in both groups, whereas SDoverall significantly differed between them. The SDoverall differed the most in the Roll axes of groups N (0. 87°) and V (0.58°). The Σ and σ values were lower in all axes of group V than in group N. Despite the initial deflation target of - 70 kPa, the pressure in VIDs reached - 5 kPa at the end of treatment. However, weekly deflation apparently maintained pressure at - 20 kPa. Effective pressure control in VIDs can reduce patient-by-patient variation and improve setup reproducibility for individual patients, consequently resulting in small variations among overall setup errors.
期刊介绍:
The purpose of the journal Radiological Physics and Technology is to provide a forum for sharing new knowledge related to research and development in radiological science and technology, including medical physics and radiological technology in diagnostic radiology, nuclear medicine, and radiation therapy among many other radiological disciplines, as well as to contribute to progress and improvement in medical practice and patient health care.