TBS-BAO: fully automated beam angle optimization for IMRT guided by a total-beam-space reference plan

Author(s):  
Bastiaan Wilhelmus Klaas Schipaanboord ◽  
Ben J M Heijmen ◽  
Sebastiaan Breedveld

Abstract Properly selected beam angles contribute to the quality of radiotherapy treatment plans. However, the Beam Angle Optimization (BAO) problem is difficult to solve to optimality due to its non-convex discrete nature with many local minima. In this study, we propose TBS-BAO, a novel approach for solving the BAO problem, and test it for non-coplanar robotic CyberKnife radiotherapy for prostate cancer. First, an ideal Pareto-optimal reference dose distribution is automatically generated using a priori multi-criterial fluence map optimization (FMO) to generate a plan that includes all candidate beams (total-beam-space, TBS). Then, this ideal dose distribution is reproduced as closely as possible in a subsequent segmentation/beam angle optimization step (SEG/BAO), while limiting the number of allowed beams to a user-selectable preset value. SEG/BAO aims at a close reproduction of the ideal dose distribution. For each of 33 prostate SBRT patients, 18 treatment plans with different pre-set numbers of allowed beams were automatically generated with the proposed TBS-BAO. For each patient, the TBS-BAO plans were then compared to a plan that was automatically generated with an alternative BAO method (Erasmus-iCycle) and to a high-quality manually generated plan. TBS-BAO was able to automatically generate plans with clinically feasible numbers of beams (∽25), with a quality highly similar to corresponding 91-beam ideal reference plans. Compared to the alternative Erasmus-iCycle BAO approach, similar plan quality was obtained for 25-beam segmented plans, while computation times were reduced from 10.7 hours to 4.8/1.5 hours, depending on the applied pencil-beam resolution in TBS-BAO. 25-beam TBS-BAO plans had similar quality as manually generated plans with on average 48 beams, while delivery times reduced from 22.3 to 18.4/18.1 min. TBS reference plans could effectively steer the discrete non-convex BAO.

2018 ◽  
Vol 14 (12) ◽  
pp. e794-e800
Author(s):  
Dina Thompson ◽  
Kimberly Cox ◽  
James Loudon ◽  
Ivan Yeung ◽  
Woodrow Wells

Purpose: Peer review of a proposed treatment plan is increasingly recognized as an important quality activity in radiation medicine. Although peer review has been emphasized in the curative setting, applying peer review for treatment plans that have palliative intent is receiving increased attention. This study reports peer review outcomes for a regional cancer center that applied routine interprofessional peer review as a standard practice for palliative radiotherapy. Methods and Materials: Peer review outcomes for palliative radiotherapy plans were recorded prospectively for patients who began radiotherapy between October 1, 2015, and September 30, 2017. Recommended and implemented changes were recorded. The content of detailed discussions was recorded to gain insight into the complexities of palliative treatment plans considered during peer review. Results: Peer review outcomes were reviewed for 1,413 treatment plans with palliative intent. The proportions of detailed discussions and changes recommended were found to be 139 (9.8%) and 29 (2.1%), respectively. The content of detailed discussions and changes recommended was categorized. Major changes represented 75.9% of recommended changes, of which 84.2% were implemented clinically. Conclusion: Many complexities exist that are specific to palliative radiotherapy. Interprofessional peer review provides a forum for these complexities to be openly discussed and is an important activity to optimize the quality of care for patients with treatment plans that have palliative intent.


2020 ◽  
Vol 152 ◽  
pp. S1003-S1004
Author(s):  
B. Vischioni ◽  
A. Mirandola ◽  
M. Bonora ◽  
S. Ronchi ◽  
E. Mastella ◽  
...  

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4411-4411 ◽  
Author(s):  
Justin Chia ◽  
Maayan Seitelbach ◽  
Ian H. Chin-Yee ◽  
Cyrus C. Hsia

Abstract Abstract 4411 Introduction: Anemia is the most common objective manifestation of the myelodysplastic syndromes (MDS), and excessive fatigue is experienced in over 80% of patients. Transfusion is essential for the management of anemia in these patients. Past studies have investigated the age of transfused blood and its effect on outcome in various acute clinical settings such as critically ill, post-cardiac surgery, trauma, and brain injury patients. However, few studies have investigated the age of transfused blood in chronically transfused patients such as MDS and its impact on quality of life (QoL) and hemoglobin (Hb) levels in these populations. Methods: The aim of our study was to compare QoL outcomes between fresh (transfused within 7 days of donation) and standard issue (transfused between 8 to 42 days, mean 20.5 days locally) blood in highly transfusion dependent patients including those with MDS. The Functional Assessment Cancer Therapy Anemia subscale (FACT-An) was utilized for QoL assessment in a series of prospective “N-of-1” trials design. An “N-of-1” study was performed for each of the participants. Each participant was randomized to receive a total of four transfusions of fresh blood and four transfusions of standard issue blood. Randomization tables were created for each participant “N-of-1” study a priori. The participants, nurses and investigators were blinded to the age of blood administered. Prior to each transfusion, and again after 24 hours, participants completed the FACT-An survey. Post transfusion Hb levels were measured prior to a subsequent transfusion. For each FACT-An parameter and Hb level, mean results were derived for the four fresh blood transfusions and for the four standard blood transfusions. These were analyzed using an unpaired Student's t-test. Results: Twenty patients were enrolled into the study at the London Health Sciences Centre (LHSC), London, Ontario, Canada. Participants included 8 males and 12 females with a mean age of 64.5 years. There were a total of 13 MDS participants (5 males, 8 females) and seven participants (3 males, 4 females) with other diseases that required them to be transfusion dependent. At the time of abstract submission, 1 participant has completed his “N-of-1” study. For this one individual, analysis comparing the pooled results of the four fresh blood transfusions versus the pooled results of the four standard issue blood transfusions was done. No significant difference was seen between fresh blood transfusions versus standard blood transfusions for all of the FACT-An parameters and post-transfusion Hb levels. Conclusions: Improving QoL is an essential component in the management of chronic diseases such as the myelodysplastic syndromes. We have designed a series of “N-of-1” studies to detect a potential difference between fresh versus standard issue red blood cells. The preliminary data from a single participant who has completed this “N-of-1” study suggest that there is no significant difference in QoL measures and Hb levels. The study has fully enrolled and demonstrated the feasibility of this novel approach to evaluating the clinical benefits of transfusion. To our knowledge this is the first reported “N-of-1” study in transfusion. Disclosures: No relevant conflicts of interest to declare.


2018 ◽  
Vol 19 (1) ◽  
pp. 64
Author(s):  
Sadiq R Malik ◽  
Shohel Reza ◽  
MM Shakhawat Hossain

<p><span>Advancement in Cancer Therapy Technology (CTT) due to Software, Hardware and precise delivery of radiation dose has enhanced the quality of life of cancer patients. This report aims at the application of 3-D CRT (Three Dimensional Conformal Radiation Therapy) and IMRT (Intensity Modulated Radiation Therapy) for a quality of treatment. Other anatomical sites viz. Prostate, Lung, etc. may also be treated provided a better tool is applied for target delineation for which FUSION of CT and MRI images are used to ascertain differences in tissue density. This Fusion image of 3 mm slices offer accurate contouring of the tumor. The oncologist and/or physicist perform delineation of (I) GTV (Gross Tumor Volume), (II) CTV (Clinical Target Volume), (III) PTV (Planning Target Volume), (IV) TV (Treated Volume) and (V) OARs (Organs at Risk). This is done to secure conformal dose distribution and justify the clinical objectives of Tumor Control Probability (TCP) by reducing the normal tissue complication probability (NTCP). <span> </span><span> </span>The implication of this study outlines the fundamental goal of effective treatment procedures by comparing treatment plans of 3-D CRT and IMRT. Tolerance levels of dose to different organs are optimized by the analysis of random and systemic geometrical deviations, margin on target volumes, conformity index (CI), patient selection process and, of course, the shape and stage of target. The comparative parameters of treatment plans are segmented and tabulated to implicate the application of necessary tools to decide on a treatment plan for similar patients.</span></p><p><span>Bangladesh J. Nuclear Med. 19(1): 64-67, January 2016</span></p>


GIS Business ◽  
2019 ◽  
Vol 14 (4) ◽  
pp. 85-98
Author(s):  
Idoko Peter

This research the impact of competitive quasi market on service delivery in Benue State University, Makurdi Nigeria. Both primary and secondary source of data and information were used for the study and questionnaire was used to extract information from the purposively selected respondents. The population for this study is one hundred and seventy three (173) administrative staff of Benue State University selected at random. The statistical tools employed was the classical ordinary least square (OLS) and the probability value of the estimates was used to tests hypotheses of the study. The result of the study indicates that a positive relationship exist between Competitive quasi marketing in Benue State University, Makurdi Nigeria (CQM) and Transparency in the service delivery (TRSP) and the relationship is statistically significant (p<0.05). Competitive quasi marketing (CQM) has a negative effect on Observe Competence in Benue State University, Makurdi Nigeria (OBCP) and the relationship is not statistically significant (p>0.05). Competitive quasi marketing (CQM) has a positive effect on Innovation in Benue State University, Makurdi Nigeria (INVO) and the relationship is statistically significant (p<0.05) and in line with a priori expectation. This means that a unit increases in Competitive quasi marketing (CQM) will result to a corresponding increase in innovation in Benue State University, Makurdi Nigeria (INVO) by a margin of 22.5%. It was concluded that government monopoly in the provision of certain types of services has greatly affected the quality of service experience in the institution. It was recommended among others that the stakeholders in the market has to be transparent so that the system will be productive to serve the society effectively


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 775-775
Author(s):  
Debra Sheets ◽  
Stuart MacDonald ◽  
Andre Smith

Abstract Choral singing is a novel approach to reduce dementia stigma and social isolation while offering participants a sense of purpose, joy and social connection. The pervasiveness of stigma surrounding dementia remains one of the biggest barriers to living life with dignity following a diagnosis (Alzheimer Society of Canada, 2018). This paper examines how a social inclusion model of dementia care involving an intergenerational choir for people living with dementia, their care partners and high school students can reduce stigma and foster social connections. Multiple methodologies are used to investigate the effects of choir participation on cognition, stress levels, social connections, stigma, and quality of life. Results demonstrate the positive impact of choir participation and indicate that this socially inclusive intervention offers an effective, non-pharmacological alternative for older adults living with dementia in the community. Discussion focuses on the importance of instituting meaningful and engaging dementia-friendly activities at the community level.


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