SU-E-T-351: Verification of Monitor Unit Calculation for Lung Stereotactic Body Radiation Therapy Using a Secondary Independent Planning System

2014 ◽  
Vol 41 (6Part16) ◽  
pp. 305-305
Author(s):  
Y Tsuruta ◽  
M Nakamura ◽  
M Nakata ◽  
Y Miyabe ◽  
M Akimoto ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Stereotactic Body Radiation Therapy ◽  
Planning System ◽  
Monitor Unit ◽  
Stereotactic Body Radiation

scholarly journals Sensitivity of 3D Dose Verification to Multileaf Collimator Misalignments in Stereotactic Body Radiation Therapy of Spinal Tumor

2016 ◽  
Vol 15 (6) ◽  
pp. NP25-NP34 ◽  
Author(s):  
Ni Xin-ye ◽  
Lei Ren ◽  
Hui Yan ◽  
Fang-Fang Yin
Keyword(s):  
Spinal Cord ◽  
Radiation Therapy ◽  
Stereotactic Body Radiation Therapy ◽  
Spinal Tumor ◽  
Pass Rate ◽  
Field Size ◽  
Planning System ◽  
Treatment Planning System ◽  
Multileaf Collimator ◽  
Stereotactic Body Radiation

Purpose: This study aimed to detect the sensitivity of Delt 4 on ordinary field multileaf collimator misalignments, system misalignments, random misalignments, and misalignments caused by gravity of the multileaf collimator in stereotactic body radiation therapy. Methods: (1) Two field sizes, including 2.00 cm (X) × 6.00 cm (Y) and 7.00 cm (X) × 6.00 cm (Y), were set. The leaves of X1 and X2 in the multileaf collimator were simultaneously opened. (2) Three cases of stereotactic body radiation therapy of spinal tumor were used. The dose of the planning target volume was 1800 cGy with 3 fractions. The 4 types to be simulated included (1) the leaves of X1 and X2 in the multileaf collimator were simultaneously opened, (2) only X1 of the multileaf collimator and the unilateral leaf were opened, (3) the leaves of X1 and X2 in the multileaf collimator were randomly opened, and (4) gravity effect was simulated. The leaves of X1 and X2 in the multileaf collimator shifted to the same direction. The difference between the corresponding 3-dimensional dose distribution measured by Delt 4 and the dose distribution in the original plan made in the treatment planning system was analyzed with γ index criteria of 3.0 mm/3.0%, 2.5 mm/2.5%, 2.0 mm/2.0%, 2.5 mm/1.5%, and 1.0 mm/1.0%. Results: (1) In the field size of 2.00 cm (X) × 6.00 cm (Y), the γ pass rate of the original was 100% with 2.5 mm/2.5% as the statistical standard. The pass rate decreased to 95.9% and 89.4% when the X1 and X2 directions of the multileaf collimator were opened within 0.3 and 0.5 mm, respectively. In the field size of 7.00 (X) cm × 6.00 (Y) cm with 1.5 mm/1.5% as the statistical standard, the pass rate of the original was 96.5%. After X1 and X2 of the multileaf collimator were opened within 0.3 mm, the pass rate decreased to lower than 95%. The pass rate was higher than 90% within the 3 mm opening. (2) For spinal tumor, the change in the planning target volume V18 under various modes calculated using treatment planning system was within 1%. However, the maximum dose deviation of the spinal cord was high. In the spinal cord with a gravity of −0.25 mm, the maximum dose deviation minimally changed and increased by 6.8% than that of the original. In the largest opening of 1.00 mm, the deviation increased by 47.7% than that of the original. Moreover, the pass rate of the original determined through Delt 4 was 100% with 3 mm/3% as the statistical standard. The pass rate was 97.5% in the 0.25 mm opening and higher than 95% in the 0.5 mm opening A, 0.25 mm opening A, whole gravity series, and 0.20 mm random opening. Moreover, the pass rate was higher than 90% with 2.0 mm/2.0% as the statistical standard in the original and in the 0.25 mm gravity. The difference in the pass rates was not statistically significant among the −0.25 mm gravity, 0.25 mm opening A, 0.20 mm random opening, and original as calculated using SPSS 11.0 software with P > .05. Conclusions: Different analysis standards of Delt 4 were analyzed in different field sizes to improve the detection sensitivity of the multileaf collimator position on the basis of 90% throughout rate. In stereotactic body radiation therapy of spinal tumor, the 2.0 mm/2.0% standard can reveal the dosimetric differences caused by the minor multileaf collimator position compared with the 3.0 mm/3.0% statistical standard. However, some position derivations of the misalignments that caused high dose amount to the spinal cord cannot be detected. However, some misalignments were not detected when a large number of multileaf collimator were administered into the spinal cord.

Evaluation of a commercial automatic treatment planning system for liver stereotactic body radiation therapy treatments

2018 ◽  
Vol 46 ◽  
pp. 153-159 ◽  
Author(s):  
Elena Gallio ◽  
Francesca Romana Giglioli ◽  
Andrea Girardi ◽  
Alessia Guarneri ◽  
Umberto Ricardi ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Treatment Planning ◽  
Stereotactic Body Radiation Therapy ◽  
Planning System ◽  
Treatment Planning System ◽  
Stereotactic Body Radiation ◽  
Automatic Treatment

scholarly journals Can the PTV Volume Be Used to Predict the Better Solution in Manual and Automatic Planning Using the Pinnacle Treatment Planning System for Lung Stereotactic Body Radiation Therapy?

2021 ◽  
Author(s):  
Yanhua Duan ◽  
Yan Shao ◽  
Hua Chen ◽  
Hao Wang ◽  
Hengle Gu ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Treatment Planning ◽  
Roc Analysis ◽  
Stereotactic Body Radiation Therapy ◽  
Target Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Rank Test ◽  
Stereotactic Body Radiation ◽  
Lung Sbrt

Abstract Purpose: The plan quality of the stereotactic body radiation therapy (SBRT) plan is affected by the patient’s planning target volume (PTV). The predictability of PTV volume and cut-off points were investigated to judge the suitability of manual and automatic plans for lung SBRT patients.Methods: The manual and automatic SBRT plans were retrospectively designed using the Pinnacle 16.2 treatment planning system (TPS) for 98 lung cancer patients. the suitability of manual and automatic plans for each patient is comprehensively evaluated. Receiver operating characteristic (ROC) analysis was used to investigate the predictability of PTV volume and determine the cut-off point. Once the cut-off point exists, all patients were divided into two groups according to this cut-off point. The Wilcoxon signed-rank test was performed for the dosimetric comparisons between the two groups. Results: ROC analysis showed that PTV volume (AUC [Area under curve]: 0.918, p= 0.005) has diagnostic power to predict the suitability of manual and automatic plans for lung SBRT patients. The cut-off points of 22.675cc were selected for PTV volume. Regardless of some comparable results, the CI, GI, V10, and V20 of automatic plans were found to be better than manual plans below the cut-off points, and the manual plan is superior to the automatic plan in HI, GI, heart d15cc, V10, V20 above the cut-off points.Conclusion: The PTV volume of cut-off points (22.675cc) are predictive of the suitability of manual and automatic plan using Pinnacle TPS for lung SBRT patients. Automatic plans were recommended for patients with PTV volumes less than 22.675cc, and manual plans can be tried for patients with larger PTV volumes.

scholarly journals GTV volume estimation using different mode of computer tomography for lung tumors in stereotactic body radiation therapy

2019 ◽  
Vol 25 (1) ◽  
pp. 29-34
Author(s):  
Ramaa Lingaiah ◽  
Md Abbas Ali ◽  
Ummay Kulsum ◽  
Muhtasim Aziz Muneem ◽  
Karthick Raj Mani ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Stereotactic Body Radiation Therapy ◽  
Lung Tumors ◽  
Planning System ◽  
Treatment Planning System ◽  
Ct Scans ◽  
4D Ct ◽  
Stereotactic Body Radiation ◽  
Varian Medical System ◽  
Helical Scan

Abstract Aim: To estimate the Gross Tumor Volume (GTV) using different modes (axial, helical, slow, KV-CBCT & 4D-CT) of computed tomography (CT) in pulmonary tumors. Materials & Methods: We have retrospectively included ten previously treated case of carcinoma of primary lung or metastatic lung using Stereotactic Body Radiation Therapy (SBRT) in this study. All the patients underwent 4 modes of CT scan Axial, Helical, Slow & 4D-CT using GE discovery 16 Slice PET-CT scanner and daily KV-CBCT for the daily treatment verification. For standardization, all the patients underwent different modes of scan using 2.5 mm slice thickness, 16 detectors rows and field of view of 400mm. Slow CT was performed using axial mode scan by increasing the CT tube rotation time (typically 3 – 4 sec.) as per the breathing period of the patients. 4D-CT scans were performed and the entire respiratory cycle was divided into ten phases. Maximum Intensity Projections (MIP), Minimum Intensity Projections (MinIP) and Average Intensity Projections (AvIP) were derived from the 10 phases. GTV volumes were delineated for all the patients in all the scanning modes (GTVAX - Axial, GTVHL - Helical, GTVSL – Slow, GTVMIP -4DCT and GTVCB – KV-CBCT) in the Eclipse treatment planning system version 11.0 (M/S Varian Medical System, USA). GTV volumes were measured, documented and compared with the different modes of CT scans. Results: The mean ± standard deviation (range) for MIP, slow, axial, helical & CBCT were 36.5 ± 40.5 (2.29 – 87.0), 35.38 ± 39.52 (2.1 – 82), 31.95 ± 37.29 (1.32 – 66.9), 28.98 ± 33.36 (1.01 – 65.9) & 37.16 ± 42.23 (2.29 – 92). Overall underestimation of helical scan and axial scan compared to MIP is 21% and 12.5%. CBCT and slow CT volume has a good correlation with the MIP volume. Conclusion: For SBRT in lung tumors better to avoid axial and helical scan for target delineation. MIP is a still a golden standard for the ITV delineation, but in the absence of 4DCT scanner, Slow CT and KV-CBCT data may be considered for ITV delineation with caution.

Can total psoas area predict toxicity after stereotactic body radiation therapy in borderline resectable and locally advanced pancreatic cancers?

2017 ◽  
Vol 35 (4_suppl) ◽  
pp. 455-455
Author(s):  
Will Jin ◽  
Eric Mellon ◽  
Jessica M. Frakes ◽  
Gilbert Murimwa ◽  
Pamela Joy Hodul ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Overall Survival ◽  
Radiation Therapy ◽  
Nutritional Status ◽  
Stereotactic Body Radiation Therapy ◽  
Locally Advanced ◽  
Planning System ◽  
Treatment Planning System ◽  
Borderline Resectable ◽  
Stereotactic Body Radiation

455 Background: Total Psoas Area (TPA), a marker of sarcopenia, found clinical utility as an independent predictor of clinical outcomes in gastrointestinal cancers as a proxy for nutritional status. Our study evaluated the relationship of TPA and other proxies of nutrition like Body Mass Index (BMI) and Body Surface Area (BSA) with outcomes in Borderline Resectable Pancreatic Cancer (BRPC) and Locally Advanced Pancreatic Cancer (LAPC) patients receiving Stereotactic Body Radiation Therapy (SBRT). Methods: In retrospective analysis of an IRB approved database, 183 BRPC and LAPC patients treated with SBRT from 2009-2016 met our selection criteria. Patients underwent gemcitabine based or FOLFIRINOX chemotherapy for 3 months prior to SBRT. Eligible patients were those with pre-SBRT planning CT imaging on Pinnacle, a treatment planning system, and an identifiable L4 vertebra. Bilateral psoas muscles were manually contoured at the L4 vertebral level. This area was normalized by patient height (median = 876.505 mm2/m). ROC curves were created for TPA, BMI and BSA. Toxicities were evaluated by binomial logistic regression; survival functions were evaluated by Kaplan-Meier. Significance was set at p < 0.05. Results: Low TPA (OR = 1.903, p = 0.036) and BSA (OR = 1.836 p = 0.048) were predictive of acute toxicities but only TPA was predictive of Grade 3+ acute toxicities (OR = 10.24, p = 0.040). Both findings were independent of tumor resectability. No association was found between TPA/BMI/BSA and late toxicities, overall survival, local progression or local recurrence. However, BRPC patients survived longer (median = 21.98 months) than their LAPC (median = 16.2 months) counterparts (p = 0.002), independent of nutritional status. Conclusions: Pre-SBRT TPA measurement is readily available and more specific than BMI or BSA as a predictor of serious acute radiotoxic complications following SBRT in BRPC/LAPC patients. However, tumor resectability remains as the only predictor of overall survival in this cohort. Whether initial pre-chemo TPA may predict acute toxicity related to chemotherapy and guide individualization of systemic regimen warrants further investigation.

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