Radiation Medicine Commons^™

Monitor Unit (Mu) Validation Using Various Types Of Dosimeters For Commissioning Small Field In Eclipse™ Treatment Planning System, Sammuel Mamesa

Chulalongkorn University Theses and Dissertations (Chula ETD)

The objective of this study was to investigate the differences of calculated MU between commissioning using corrected FOF from single detector and commissioning using average uncorrected FOF from three detectors. Measurements were carried out on 6 MV flattened photon beams from 1x1 cm2 to 10x10 cm2. Four detectors were utilized to measure depth doses and beam profiles: IBA CC01, IBA PFD, IBA EFD and Sun Nuclear EDGE. For FOF determination, Sun Nuclear EDGE was not used. The determination of FOF was classified into corrected FOF according to IAEA/AAPM TRS 483 and uncorrected FOF from three detectors. Commissioning was undertaken in …

Ct Number And Electron Density Relationship For Photon Dose Calculation In Head And Neck, Chest, Spine And Pelvic Regions, Siriporn Wong

Chulalongkorn University Theses and Dissertations (Chula ETD)

CT images supply the HU information that relates to electron density (ρe). The ρe is important for tissue inhomogeneity correction for accurate dose calculation. The purpose of this study was to evaluate the dosimetric effect on CT images on different kVp setting using single HU-ρe curve. Anthropomorphic phantom was scanned using Siemens-SOMATOM Definition AS with 120 kVp setting and used as a reference image set. The procedures were repeated with DECT option (80/140 kVp), 80 and 140 kVp. The 120 kVp HU-ρe relationship curve from Gammex 467 tissue characterization phantom was created and applied into Eclipse treatment planning system. The …

The Determination Of Optimal Protocol For Digital Chest Tomosynthesis, Sarawut Tongkum

Chulalongkorn University Theses and Dissertations (Chula ETD)

Recently, digital chest tomosynthesis (DTS) is introduced as alternative technique in digital chest radiography for evaluating pulmonary disease and enhancing the internal structures in different slices. However, the radiation dose is higher compared to general chest radiography. The present study was to determine the optimal protocol for DTS in order to reduce the radiation dose to patients while maintaining the image quality. The multipurpose chest phantom N1 "LUNGMAN'' was scanned by digital radiographic systems model Definium 8000.Such phantom was inserted with simulated nodules with size diameter of 3, 5, 8, 10, 12 mm, and the data were acquired using chest …

Radiation Dose And Image Quality In Chest Region Using Single- And Dual-Energy Ct: Phantom Study, Taninchai Jutawiriya

Chulalongkorn University Theses and Dissertations (Chula ETD)

Chest CT examinations are routinely performed by using single energy protocol (SE). As CT had been evolved by using dual energy protocol (DE), the patients with underlying lung nodules or pulmonary nodules will be followed up by CT examination several times. The purpose of this study is to study the radiation dose and image quality between single-energy CT (SECT) and dual-energy CT (DECT) protocols in chest phantom at King Chulalongkorn Memorial Hospital. The Lungman Kyoto Kagaku phantom inserted by five simulated lesions of various diameters was scanned by dual-source CT system (Somatom Force, Siemens Healthineers). The acquisition protocols consist of …

The Dosimetric Evaluation On Photon Energy Effect For Cervical Carcinoma In 3d-Crt, Imrt, And Vmat Plans, Vanida Poolnapol

Chulalongkorn University Theses and Dissertations (Chula ETD)

In the previous time, 3D-CRT technique has been considered as the primary treatment for cervical cancer treatment. Nowadays, advanced techniques, IMRT and VMAT, are used to treat because of the dosimetric and clinical benefit over 3D-CRT technique. However, each of these technique generates difference outcomes. The purpose of this study was to investigate the dosimetric outcomes between 6 and 15 MV photon energies in each 4 fields box 3D-CRT, 9 fields IMRT, and 2 arcs VMAT plans of five advanced cervical cancers using parameters of D95%, TC, HI, CI, CN from PTV, V45 Gy and V50 Gy from OARs, NTID, …

Nfatc3 And Vip In Idiopathic Pulmonary Fibrosis And Chronic Obstructive Pulmonary Disease, A. M. Szema, E. Forsyth, B. Ying, S. A. Hamidi, J. J. Chen, S. Hwang, J. C. Li, D. S. Dwyer, J. M. Ramiro-Diaz, L. V. Gonzalez Bosc, +1 Additional Author

Journal Articles

No abstract provided.

Imaging The Transgender Patient, Tanya M. Custer, Kim Michael

Posters and Presentations: Medical Imaging & Therapeutic Sciences

Within the health care system, lesbian, gay, bisexual, and transgender (LGBT) persons face many obstacles that lead to health disparities. These disparities include social stigma, lack of provider knowledge and training, lack of sufficient health insurance coverage, and layout of physician practice. As noted by the Joint Commission, federal law prohibits the discrimination of individuals based on race, color, national origin, age, disability, and sex within the health care system.1 It is essential for all health care providers to be educated on the best practices in regard to caring for the LGBT patient.

The focus of this exhibit is to …

Ncrp Program Area Committee 7: Radiation Education, Risk Communication, Outreach, And Policy, S. M. Becker, P. A. Locke

Community & Environmental Health Faculty Publications

Recognizing the central importance of effective communication, education, and policy across all of the domains of radiation safety and radiation protection, the National Council on Radiation Protection and Measurements (NCRP) established a new committee in 2013. Program Area Committee 7 (PAC 7) was created to develop projects and provide guidance on Radiation Education, Risk Communication, Outreach, and Policy. After identifying individuals with relevant expertise who were willing to serve, the Committee held its inaugural meeting in 2014. In 2015, the Committee increased its membership and began carrying out an expanded program of activities. One area of activity has involved providing …

Adding Genetic Risk Score To Family History Identifies Twice As Many High-Risk Men For Prostate Cancer: Results From The Prostate Cancer Prevention Trial, H. Chen, X. Liu, C. B. Brendler, D. P. Ankerst, R. J. Leach, P. J. Goodman, M. S. Lucia, C. M. Tangen, L. Wang, J. Xu, +8 Additional Authors

Journal Articles

No abstract provided.

Defining The Value Framework For Prostate Brachytherapy Using Patient-Centered Outcome Metrics And Time-Driven Activity-Based Costing, N. G. Thaker, T. J. Pugh, U. Mahmood, S. Choi, T. E. Spinks, N. E. Martin, T. T. Sio, B. W. Cox, L. Potters, S. J. Frank, +8 Additional Authors

Journal Articles

No abstract provided.

High-Dose Hypofractionated Radiotherapy Is Effective And Safe For Tumors In The Head-And-Neck, S. Teckie, B. H. Lok, S. Rao, S. I. Gutiontov, Y. Yamada, S. L. Berry, M. J. Zelefsky, N. Y. Lee

Journal Articles

No abstract provided.

Effect Of The Normalized Prescription Isodose Line On The Magnitude Of Monte Carlo Vs. Pencil Beam Target Dose Differences For Lung Stereotactic Body Radiotherapy, D. Zheng, Q. Zhang, X. Liang, X. Zhu, V. Verma, S. Wang, S. Zhou

Journal Articles

© This work is licensed under a Creative Commons Attribution 3.0 Unported License. In lung stereotactic body radiotherapy (SBRT) cases, the pencil beam (PB) dose calculation algorithm is known to overestimate target dose as compared to the more accurate Monte Carlo (MC) algorithm. We investigated whether changing the normalized prescription isodose line affected the magnitude of MC vs. PB target dose differences. Forty-eight patient plans and twenty virtual-tumor phantom plans were studied. For patient plans, four alternative plans prescribed to 60%, 70%, 80%, and 90% isodose lines were each created for 12 patients who previously received lung SBRT treatments. Using …

Quinomycin A Targets Notch Signaling Pathway In Pancreatic Cancer Stem Cells, S. Ponnurangam, P. R. Dandawate, A. Dhar, O. W. Tawfik, R. R. Parab, P. D. Mishra, P. Ranadive, R. Sharma, G. Mahajan, D. Subramaniam, +7 Additional Authors

Journal Articles

Cancer stem cells (CSCs) appear to explain many aspects of the neoplastic evolution of tumors and likely account for enhanced therapeutic resistance following treatment. Dysregulated Notch signaling, which affects CSCs plays an important role in pancreatic cancer progression. We have determined the ability of Quinomycin to inhibit CSCs and the Notch signaling pathway. Quinomycin treatment resulted in significant inhibition of proliferation and colony formation in pancreatic cancer cell lines, but not in normal pancreatic epithelial cells. Moreover, Quinomycin affected pancreatosphere formation. The compound also decreased the expression of CSC marker proteins DCLK1, CD44, CD24 and EPCAM. In addition, flow cytometry …

Target Dose Conversion Modeling From Pencil Beam (Pb) To Monte Carlo (Mc) For Lung Sbrt, D. Zheng, X. Zhu, Q. Zhang, X. Liang, W. Zhen, C. Lin, V. Verma, S. Wang, A. Wahl, C. Zhang, +2 Additional Authors

Journal Articles

© 2016 The Author(s). Background: A challenge preventing routine clinical implementation of Monte Carlo (MC)-based lung SBRT is the difficulty of reinterpreting historical outcome data calculated with inaccurate dose algorithms, because the target dose was found to decrease to varying degrees when recalculated with MC. The large variability was previously found to be affected by factors such as tumour size, location, and lung density, usually through sub-group comparisons. We hereby conducted a pilot study to systematically and quantitatively analyze these patient factors and explore accurate target dose conversion models, so that large-scale historical outcome data can be correlated with more …

Predicting Treatment Related Imaging Changes (Trics) After Radiosurgery For Brain Metastases Using Treatment Dose And Conformality Metrics., B. F. Taylor, J. P. Knisely, J. M. Qian, J. B. Yu, V. L. Chiang

Journal Articles

Purpose: Treatment-related imaging changes (TRICs) after stereotactic radiosurgery (SRS) involves the benign transient enlargement of radiographic lesions after treatment. Identifying the radiation dose volumes and conformality metrics associated with TRICs for different post-treatment periods would be helpful and improve clinical decision making.

Methods: 367 metastases in 113 patients were treated using Gamma Knife SRS between 1/1/2007-12/31/2009. Each metastasis was measured at each imaging follow-up to detect TRICs (defined as ≥ 20% increase in volume). Fluctuations in small volume lesions (less than 108 mm

Results: From 0-6 months, all measures correlated with the incidence of TRICs (p

Conclusions: All metrics except …

A Contemporary Dose Selection Algorithm For Stereotactic Radiosurgery In The Treatment Of Brain Metastases - An Initial Report., R. J. Colaco, J. B. Yu, J. S. Bond, R. S. Bindra, J. N. Contessa, J. P. S. Knisely, V. L. Chiang

Journal Articles

Indications and treatment goals for SRS have changed since the publication of RTOG 90-05. We present initial retrospective outcomes from a new dose selection algorithm in use at our institution felt to be more contemporary with doses being used in the radiosurgery community today and report our local control and toxicity outcomes. This dose selection algorithm will be subject to a forthcoming prospective phase 2 trial.To evaluate safety and efficacy of an institutional dose selection algorithm in the treatment of brain metastases (BM) with single fraction radio-surgery (SRS).The medical records of 65 patients with ≤10 BM treated with GK at …

Cytoplasmic, Full Length And Novel Cleaved Variant, Tblr1 Reduces Apoptosis In Prostate Cancer Under Androgen Deprivation, G. Daniels, X. Zhang, X. Zhong, L. Santiago, L. H. Wang, X. Wu, J. Y. Zhang, F. Liang, X. Li, P. Lee, +6 Additional Authors

Journal Articles

No abstract provided.

The Utilization Of The Anatomage Virtual Dissection Table In The Education Of Imaging Science Students, Tanya M. Custer, Kim Michael

Posters and Presentations: Medical Imaging & Therapeutic Sciences

Objectives: The purpose of this research was to investigate the use of the Anatomage Virtual Dissection Table in the education of imaging science students and to assess the beliefs and perceptions of the students in regard to using the Table for teaching imaging-based anatomy & pathology.

Subjects & Methods: Study participants included 17 medical imaging students to include 9 Diagnostic Medical Sonography students, 2 Magnetic Resonance Imaging students, 2 Nuclear Medicine Technology students, 2 Radiation Therapy students and 2 Cardiovascular Interventional Technology students. Data was collected through focus groups and course/instructor evaluations. The researchers followed Creswell’s procedure for data analysis …

Weighing The Risks And Benefits Of Radiation Exposure And Diagnostic X-Rays In Children, Leah Costello

Physician Assistant Scholarly Project Posters

The number of X-rays, specifically CT scans, performed on patients in the United States is increasing exponentially every year. Children are at most risk for long term damage from this increase in radiation exposure. This study explores how much risk children are being exposed to and how we can, as practitioners, make informed decisions about when or when not to order CT scans. The purpose of this paper is to provide practitioners the information needed to help patients decide if the long-term risks of cancer from medical radiation outweigh the potential benefit of diagnostic or therapeutic radiation. The review of …

Marcks Regulates Growth And Radiation Sensitivity And Is A Novel Prognostic Factor For Glioma, James S. Jardoe, Joshua C. Anderson, Christine W. Duarte, Tapan Mehta, Somaira Nowsheen, Patrick H. Hicks, Alexander C. Whitley, Timothy Rohrbach, Raymond O. Mccubrey, Sherard Chiu, Tamara M. Burleson, James A. Bonner, G. Yancey Gillespie, Eddy S. Yang, Christopher D. Willey

Richard Bland Faculty Works

Purpose

This study assessed whether Myristoylated Alanine Rich C-Kinase Substrate (MARCKS) can regulate glioblastoma (GBM) growth, radiation sensitivity and clinical outcome.

Experimental Design

MARCKS protein levels were analyzed in five GBM explant cell lines and eight patient-derived xenograft tumors by immunoblot, and these levels were correlated to proliferation rates and intracranial growth rates, respectively. Manipulation of MARCKS protein levels was assessed by lentiviral-mediated shRNA knockdown in the U251 cell line and MARCKS over-expression in the U87 cell line. The effect of manipulation of MARCKS on proliferation, radiation sensitivity and senescence was assessed. MARCKS gene expression was correlated with survival outcomes …