keyword
MENU ▼
Read by QxMD icon Read
search

Inverse Planning

keyword
https://www.readbyqxmd.com/read/28325472/dosimetric-comparison-between-treatment-plans-of-patients-treated-with-low-dose-rate-vs-high-dose-rate-interstitial-prostate-brachytherapy-as-monotherapy-initial-findings-of-a-randomized-clinical-trial
#1
T Major, C Polgár, K Jorgo, G Stelczer, P Ágoston
PURPOSE: The aim of this study was to compare the dosimetry of intraoperative dose plans of prostate cancer patients treated with low-dose-rate (LDR) and high-dose-rate (HDR) interstitial brachytherapy (BT). METHODS AND MATERIALS: A randomized clinical trial was initiated at our institution to compare the results and side effects of LDR and HDR BT as monotherapy in the treatment of early, organ-confined prostate cancer patients. Eighty-seven patients were randomly assigned to receive HDR afterloading BT with one fraction of 19 Gy or permanent LDR (125)I seed BT with 145 Gy...
March 15, 2017: Brachytherapy
https://www.readbyqxmd.com/read/28306555/assessment-of-dosimetric-impact-of-system-specific-geometric-distortion-in-an-mri-only-based-radiotherapy-workflow-for-prostate
#2
C Gustafsson, F Nordström, E Persson, J Brynolfsson, L E Olsson
Dosimetric errors in a magnetic resonance imaging (MRI) only radiotherapy workflow may be caused by system specific geometric distortion from MRI. The aim of this study was to evaluate the impact on planned dose distribution and delineated structures for prostate patients, originating from this distortion. A method was developed, in which computer tomography (CT) images were distorted using the MRI distortion field. The displacement map for an optimized MRI treatment planning sequence was measured using a dedicated phantom in a 3 T MRI system...
March 17, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28299284/integral-dose-based-inverse-optimization-may-reduce-side-effects-in-radiotherapy-of-prostate-carcinoma
#3
Ivaylo B Mihaylov
PURPOSE: The purpose of this work is to apply a novel inverse optimization approach, based on utilization of quantitative imaging information in the optimization function, to prostate carcinoma. MATERIALS AND METHODS: This new inverse optimization algorithm relies upon quantitative information derived from computed tomography (CT) imaging studies. The Hounsfield numbers of the CT voxels are converted to physical density, which in turn is used to calculate voxel mass and the corresponding integral dose, by summation over the product of dose and mass in each dose voxel...
2017: Frontiers in Oncology
https://www.readbyqxmd.com/read/28297348/inverse-treatment-planning-for-spinal-robotic-radiosurgery-an-international-multi-institutional-benchmark-trial
#4
Oliver Blanck, Lei Wang, Wolfgang Baus, Jimm Grimm, Thomas Lacornerie, Joakim Nilsson, Sergii Luchkovskyi, Isabel Palazon Cano, Zhenyu Shou, Myriam Ayadi, Harald Treuer, Romain Viard, Frank-Andre Siebert, Mark K H Chan, Guido Hildebrandt, Jürgen Dunst, Detlef Imhoff, Stefan Wurster, Robert Wolff, Pantaleo Romanelli, Eric Lartigau, Robert Semrau, Scott G Soltys, Achim Schweikard
Stereotactic radiosurgery (SRS) is the accurate, conformal delivery of high-dose radiation to well-defined targets while minimizing normal structure doses via steep dose gradients. While inverse treatment planning (ITP) with computerized optimization algorithms are routine, many aspects of the planning process remain user-dependent. We performed an international, multi-institutional benchmark trial to study planning variability and to analyze preferable ITP practice for spinal robotic radiosurgery. 10 SRS treatment plans were generated for a complex-shaped spinal metastasis with 21 Gy in 3 fractions and tight constraints for spinal cord (V14Gy<2 cc, V18Gy<0...
May 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28297346/initial-evaluation-of-automated-treatment-planning-software
#5
Dawn Gintz, Kujtim Latifi, Jimmy Caudell, Benjamin Nelms, Geoffrey Zhang, Eduardo Moros, Vladimir Feygelman
Even with advanced inverse-planning techniques, radiation treatment plan optimization remains a very time-consuming task with great output variability, which prompted the development of more automated approaches. One commercially available technique mimics the actions of experienced human operators to progressively guide the traditional optimization process with automatically created regions of interest and associated dose-volume objectives. We report on the initial evaluation of this algorithm on 10 challenging cases of locoreginally advanced head and neck cancer...
May 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28297298/dosimetric-and-volumetric-changes-in-the-rectum-and-bladder-in-patients-receiving-cbct-guided-prostate-imrt-analysis-based-on-daily-cbct-dose-calculation
#6
David Pearson, Sukhdeep K Gill, Nina Campbell, Krishna Reddy
Delivered dose can be calculated by transferring the planned treatment beams onto the daily CBCT. Bladder and rectum volumetric doses were calculated and correlated to the daily bladder and rectum fullness. Patients for this study underwent hypofractionated prostate IMRT to 70 Gy in 28 fractions. Daily CBCT was utilized for image guidance. A clinically acceptable plan was created using a CTV-to-PTV uniform margin of 5 mm. Image fusion was performed to transfer the bladder and rectum contours onto each CBCT...
November 2016: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28295127/the-crush-index-orthopedic-trauma-as-an-economic-indicator
#7
Armin Arshi, Justin H Barad, Riki K Patel, J Ben Allis, Nelson F Soohoo, Eric E Johnson
The purpose of this study was to evaluate the relationship between economic activity and the incidence of high-energy orthopedic trauma. California's Office of Statewide Health Planning and Development patient discharge database was queried to identify monthly orthopedic trauma incidence from 1995 to 2010. Patient inclusion required 1 diagnosis code and 1 associated procedural code for fractures of the femur, tibia, ankle, pelvis, or acetabulum. Data on composite market indices, energy and transportation use, and unemployment were obtained from government sources...
March 14, 2017: Orthopedics
https://www.readbyqxmd.com/read/28294159/to-find-a-better-dosimetric-parameter-in-the-predicting-of-radiation-induced-lung-toxicity-individually-ventilation-perfusion-or-ct-based
#8
Lin-Lin Xiao, Guoren Yang, Jinhu Chen, Xiaohui Wang, Qingwei Wu, Zongwei Huo, Qingxi Yu, Jinming Yu, Shuanghu Yuan
This study aimed to find a better dosimetric parameter in predicting of radiation-induced lung toxicity (RILT) in patients with non-small cell lung cancer (NSCLC) individually: ventilation(V), perfusion (Q) or computerized tomography (CT) based. V/Q single-photon emission computerized tomography (SPECT) was performed within 1 week prior to radiotherapy (RT). All V/Q imaging data was integrated into RT planning system, generating functional parameters based on V/Q SPECT. Fifty-seven NSCLC patients were enrolled in this prospective study...
March 15, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28292645/one-hand-two-hands-two-people-prospective-sensorimotor-control-in-children-with-autism
#9
Caterina Ansuini, Jessica Podda, Francesca Maria Battaglia, Edvige Veneselli, Cristina Becchio
Where grasps are made reveals how grasps are planned. The grasp height effect predicts that, when people take hold of an object to move it to a new position, the grasp height on the object is inversely related to the height of the target position. In the present study, we used this effect as a window into the prospective sensorimotor control of children with autism spectrum disorders without accompanying intellectual impairment. Participants were instructed to grasp a vertical cylinder and move it from a table (home position) to a shelf of varying height (target position)...
March 2, 2017: Developmental Cognitive Neuroscience
https://www.readbyqxmd.com/read/28274404/in-vivo-dosimetry-with-optically-stimulated-luminescent-dosimeters-for-conformal-and-intensity-modulated-radiation-therapy-a-2-year-multicenter-cohort-study
#10
Adam C Riegel, Yu Chen, Ajay Kapur, Laura Apicello, Abraham Kuruvilla, Anthony J Rea, Abolghassem Jamshidi, Louis Potters
PURPOSE: Optically stimulated luminescent dosimeters (OSLDs) are utilized for in vivo dosimetry (IVD) of modern radiation therapy techniques such as intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT). Dosimetric precision achieved with conventional techniques may not be attainable. In this work, we measured accuracy and precision for a large sample of clinical OSLD-based IVD measurements. METHODS AND MATERIALS: Weekly IVD measurements were collected from 4 linear accelerators for 2 years and were expressed as percent differences from planned doses...
March 2017: Practical Radiation Oncology
https://www.readbyqxmd.com/read/28270208/aortic-length-measurements-for-pulse-wave-velocity-calculation-manual-2d-vs-automated-3d-centreline-extraction
#11
Arna van Engelen, Miguel Silva Vieira, Isma Rafiq, Marina Cecelja, Torben Schneider, Hubrecht de Bliek, C Alberto Figueroa, Tarique Hussain, Rene M Botnar, Jordi Alastruey
BACKGROUND: Pulse wave velocity (PWV) is a biomarker for the intrinsic stiffness of the aortic wall, and has been shown to be predictive for cardiovascular events. It can be assessed using cardiovascular magnetic resonance (CMR) from the delay between phase-contrast flow waveforms at two or more locations in the aorta, and the distance on CMR images between those locations. This study aimed to investigate the impact of different distance measurement methods on PWV. We present and evaluate an algorithm for automated centreline tracking in 3D images, and compare PWV calculations using distances derived from 3D images to those obtained from a conventional 2D oblique-sagittal image of the aorta...
March 8, 2017: Journal of Cardiovascular Magnetic Resonance
https://www.readbyqxmd.com/read/28268849/a-stochastic-framework-for-spot-scanning-particle-therapy
#12
Marc Robini, Yuemin Zhu, Wanyu Liu, Isabelle Magnin
In spot-scanning particle therapy, inverse treatment planning is usually limited to finding the optimal beam fluences given the beam trajectories and energies. We address the much more challenging problem of jointly optimizing the beam fluences, trajectories and energies. For this purpose, we design a simulated annealing algorithm with an exploration mechanism that balances the conflicting demands of a small mixing time at high temperatures and a reasonable acceptance rate at low temperatures. Numerical experiments substantiate the relevance of our approach and open new horizons to spot-scanning particle therapy...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28266874/development-and-validation-of-a-scale-to-measure-adolescent-sexual-and-reproductive-health-stigma-results-from-young-women-in-ghana
#13
Kelli Stidham Hall, Abubakar Manu, Emmanuel Morhe, Lisa H Harris, Dana Loll, Elizabeth Ela, Giselle Kolenic, Jessica L Dozier, Sneha Challa, Melissa K Zochowski, Andrew Boakye, Richard Adanu, Vanessa K Dalton
Young women's experiences with sexual and reproductive health (SRH) stigma may contribute to unintended pregnancy. Thus, stigma interventions and rigorous measures to assess their impact are needed. Based on formative work, we generated a pool of 51 items on perceived stigma around different dimensions of adolescent SRH and family planning (sex, contraception, pregnancy, childbearing, abortion). We tested items in a survey study of 1,080 women ages 15 to 24 recruited from schools, health facilities, and universities in Ghana...
March 7, 2017: Journal of Sex Research
https://www.readbyqxmd.com/read/28263920/healthcare-costs-and-utilization-for-patients-age-50-64-years-with-acute-myeloid-leukemia-treated-with-chemotherapy-or-with-chemotherapy-and-allogeneic-hematopoietic-cell-transplantation
#14
Jaime M Preussler, Christa L Meyer, Lih-Wen Mau, Navneet S Majhail, Ellen Denzen, Kristen C Edsall, Stephanie H Farnia, Wael Saber, Linda J Burns, David J Vanness
The primary aim of this study was to describe healthcare costs and utilization during the first year after a diagnosis of acute myeloid leukemia (AML) for privately insured non-Medicare patients in the United States (US) aged 50-64 years who were treated with either chemotherapy or chemotherapy and allogeneic hematopoietic cell transplantation (alloHCT). MarketScan (Truven Health Analytics) adjudicated total payments for inpatient, outpatient and prescription drug claims from 2007-2011 were used to estimate costs from the health system perspective...
March 2, 2017: Biology of Blood and Marrow Transplantation
https://www.readbyqxmd.com/read/28257542/disparities-in-cancer-survivorship-indicators-in-the-deep-south-based-on-brfss-data-recommendations-for-survivorship-care-plans
#15
Renee A Desmond, Bradford E Jackson, John W Waterbor
OBJECTIVES: The purpose of this investigation was to describe cancer survivorship based on the Behavioral Risk Factor Surveillance System (BRFSS) cancer survivorship modules in Alabama, Georgia, and Mississippi, conducted in 2012 and 2014, and to investigate disparities across the US Deep South region. METHODS: The optional BRFSS cancer survivorship module was introduced in 2009. Data from Alabama (2012), Georgia (2012), and Mississippi (2014) were assessed. Demographic factors were analyzed through weighted regression for risk of receiving cancer treatment summary information and follow-up care...
March 2017: Southern Medical Journal
https://www.readbyqxmd.com/read/28257434/determinants-of-geographic-inequalities-in-hpv-vaccination-in-the-most-populated-region-of-france
#16
Delphine Héquet, Roman Rouzier
BACKGROUND: In France, there are recommendations and reimbursements for human papillomavirus (HPV) vaccination but no HPV vaccination programs. Therefore, vaccination is largely determined by parents' initiative, which can lead to inequalities. The objective of this study was to determine the factors associated with poorer vaccination coverage rates in the most populated region of France. METHODS: The data of this study were obtained from the National Health Insurance between 2011 and 2013...
2017: PloS One
https://www.readbyqxmd.com/read/28243076/alpha-1-antitrypsin-pi-z-gene-frequency-and-pi-zz-genotype-numbers-worldwide-an-update
#17
Ignacio Blanco, Patricia Bueno, Isidro Diego, Sergio Pérez-Holanda, Francisco Casas-Maldonado, Cristina Esquinas, Marc Miravitlles
In alpha-1 antitrypsin deficiency (AATD), the Z allele is present in 98% of cases with severe disease, and knowledge of the frequency of this allele is essential from a public health perspective. However, there is a remarkable lack of epidemiological data on AATD worldwide, and many of the data currently used are outdated. Therefore, the objective of this study was to update the knowledge of the frequency of the Z allele to achieve accurate estimates of the prevalence and number of Pi*ZZ genotypes worldwide based on studies performed according to the following criteria: 1) samples representative of the general population, 2) AAT phenotyping characterized by adequate methods, and 3) measurements performed using a coefficient of variation calculated from the sample size and 95% confidence intervals...
2017: International Journal of Chronic Obstructive Pulmonary Disease
https://www.readbyqxmd.com/read/28241931/text-mining-approach-to-predict-hospital-admissions-using-early-medical-records-from-the-emergency-department
#18
Filipe R Lucini, Flavio S Fogliatto, Giovani J C da Silveira, Jeruza L Neyeloff, Michel J Anzanello, Ricardo de S Kuchenbecker, Beatriz D Schaan
OBJECTIVE: Emergency department (ED) overcrowding is a serious issue for hospitals. Early information on short-term inward bed demand from patients receiving care at the ED may reduce the overcrowding problem, and optimize the use of hospital resources. In this study, we use text mining methods to process data from early ED patient records using the SOAP framework, and predict future hospitalizations and discharges. DESIGN: We try different approaches for pre-processing of text records and to predict hospitalization...
April 2017: International Journal of Medical Informatics
https://www.readbyqxmd.com/read/28241134/risk-of-ischemic-stroke-and-transient-ischemic-attack-is-increased-up-to-90-days-after-non-carotid-and-non-cardiac-surgery
#19
Armin J Grau, Martin Eicke, Christoph Burmeister, Roland Hardt, Eberhard Schmitt, Sieghard Dienlin
BACKGROUND: The risk of stroke after cardiac and carotid surgery is well established. In contrast, stroke risk in association with non-cardiac and non-carotid surgery and its time course are insufficiently known. We investigated the prevalence of recent and planned surgery among patients with stroke and transient ischemic attack (TIA), time dependency of stroke risk, stroke etiology, and interruption of antithrombotic medication in association with surgery. METHODS: Data on type and date of surgery and similar interventions within the last year or planned for the next 2 weeks were anonymously collected together with demographic data, vascular risk factors, stroke severity, handicap before stroke and stroke etiology within a state-wide, mandatory, hospital-based acute stroke care quality monitoring project (Rhineland-Palatinate, Germany) for 1 year (2010)...
February 28, 2017: Cerebrovascular Diseases
https://www.readbyqxmd.com/read/28236138/progression-of-kidney-disease-in-elderly-stage-3-and-4-chronic-kidney-disease-patients
#20
Pradeep Arora, Kabir Jalal, Anu Gupta, Randolph L Carter, James W Lohr
PURPOSE: The prevalence of chronic kidney disease (CKD) has been rising steadily in the elderly population. We studied the rate of progression of CKD in this population and the factors associated with progression of CKD to better identify patients who are likely to progress to ESRD. METHODS: This was an observational study including 4562 patients older than 65 years with two outpatient estimated glomerular filtration rates (eGFRs) of <60 ml/min/1.73 m(2), at least 90 days apart with no intervening eGFR >60 ml/min/1...
February 24, 2017: International Urology and Nephrology
keyword
keyword
60686
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"