선택한 단어 수는 입니다.
최소 단어 이상 선택하여야 합니다.
최소 단어 이상 선택하여야 합니다.
선택한 단어 수는 30입니다.
최대 10 단어까지만 선택 가능합니다.
최대 10 단어까지만 선택 가능합니다.
문제 정의
- The aim of this study was to analyze the impact of different control parameter of the rigid imageregistration on extend of translational and rotational adjustments in Tomotherapy. This study analyzed the automatic rigid image-registration of five groups of patients (brain, head-and-neck, lung, abdomen and pelvic patients).
제안 방법
- Additional study was performed for the correlation coefficient values for two adjustments for each group. The correlation between the vertical and pitch directions showed significant differences (-0.
- First, we calculated the systematic error for each patient, with calculation of the mean of the inter-fractional variations for each fraction during a course of treatment. The displacements of two adjustments for all patient and groups were calculated using the following equations (1) and (2).
- All patients were scanned in order to obtain MVCT images for each fraction before treatment. For each of the fractions, we compared the acquired MVCT images and planning kVCT images during the process of automatic rigid imageregistration. Figure 1.
- In this study, we analyzed by examining a total of 50 patients divided into five groups which were the brain, head-and-neck, lung, abdomen and pelvic regions. The rotational adjustments have varying deviations depending on different control parameters, and also the variations between the different resolutions were small.
- In this study, we analyzed the deviations of the systematic errors and the RMS of random errors, and the overall mean value (Μ) by using the different control parameters, and dividing the patients into five groups.
- In this study, we collected the displacement data of the translational (lateral, longitudinal and vertical) magnitudes (mm) and the rotational (pitch, roll and yaw) angles ( °) of nine cases of automatic rigid image-registration processes for all patients, and we calculated the systematic and random errors for each of the groups20, 21).
- Second, we calculated the random error for each patient, with calculation of the mean of the intra-fractional variations for each fraction during a course of treatment. For random errors of each patient per group, ∑(μR) is the standard deviation of the translational and rotational adjustments.
- The aim of this study was to analyze the impact of different control parameter of the rigid imageregistration on extend of translational and rotational adjustments in Tomotherapy. This study analyzed the automatic rigid image-registration of five groups of patients (brain, head-and-neck, lung, abdomen and pelvic patients).
- This study evaluated only two groups using the "bone" technique to verify the errors in the image-registration process.
- By comparison, we performed the analysis by examining a total of 50 patients divided into five groups which were the brain, headand-neck, lung, abdomen and pelvic groups. We also analyzed the displacement data for the translational (lateral, longitudinal and vertical) and the rotational (pitch, roll and yaw) adjustments. For accuracy of automatic image-registration using a phantom, Boswell et al.
대상 데이터
- Tomotherapy (Accuray Inc, Sunnyvale, CA, USA) is a unique type of radiation therapy. The equipment combines a linear accelerator (LINAC) with computed tomography (CT). Spiral radiation therapy is achieved by the use of a gantry head with a 360° range of rotation and couch motion8).
데이터처리
- Average and standard deviation of systematic errors (σ) for the rotational angles (°) between different image-registration components of the five groups (one-way ANOVA).
- ) is the systematic error mean value and N is the number of patients for each group in this study. For different imageregistration components and between each group, statistical analysis was performed using a one-way ANOVA (analysis of variance).
- In addition, we also analyzed the coefficient of correlation between the translational and rotational adjustments by using Pearson's product-moment coefficient to verify the correlations.
- The statistical significance was confirmed by one-way ANOVA based on the combination of "full-image" and "standard" (Table 3).
이론/모형
- 0, Philips Medical Systems, Andover, MA) and used for the contouring of the regions of interest (ROIs), the estimation of the gross tumor volume (GTV) and the identification of the organs at risks (OARs). This study used the Tomotherapy Hi-Art II treatment planning system (Accuray Inc, Sunnyvale, CA, USA).
성능/효과
- In this calculation, 66.7% of the translational variation was less than 0.05 mm (range: 0.01–0.12 mm) and 93.7% of the rotational variations were less than 0.05° (0.00–0.07°) (Table 4).
- Their results showed that systematic error variations and random error magnitudes ranged from 1.6 mm–2.6 mm for both brain and head-and-neck groups.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.