keyword
MENU ▼
Read by QxMD icon Read
search

Inverse Planning

keyword
https://www.readbyqxmd.com/read/28545231/atmospheric-sampling-on-ascension-island-using-multirotor-uavs
#1
Colin Greatwood, Thomas S Richardson, Jim Freer, Rick M Thomas, A Rob MacKenzie, Rebecca Brownlow, David Lowry, Rebecca E Fisher, Euan G Nisbet
As part of an NERC-funded project investigating the southern methane anomaly, a team drawn from the Universities of Bristol, Birmingham and Royal Holloway flew small unmanned multirotors from Ascension Island for the purposes of atmospheric sampling. The objective of these flights was to collect air samples from below, within and above a persistent atmospheric feature, the Trade Wind Inversion, in order to characterise methane concentrations and their isotopic composition. These parameters allow the methane in the different air masses to be tied to different source locations, which can be further analysed using back trajectory atmospheric computer modelling...
May 23, 2017: Sensors
https://www.readbyqxmd.com/read/28541236/attention-deficit-hyperactivity-disorder-adhd-symptoms-and-cognitive-skills-of-preschool-children
#2
L Thomaidis, A Choleva, M Janikian, G Bertou, A Tsitsika, G Giannakopoulos, D C Anagnostopoulos
Attention deficit/hyperactivity disorder (ADHD) constitutes a neurobehavioral disorder which may potentially adversely affect children's wellbeing and academic achievement. The onset of symptoms is present prior to 12 years of age, and often the symptoms are evident in the preschool years. In fact, it has been suggested that screening for ADHD symptoms may be initiated as early as four years of age. Preschool children with ADHD have been shown to present with poor pre-academic skills and might be at increased risk for numerous school-related problems, including functional impairment during elementary school years and persistent poor academic performance thereafter...
January 2017: Psychiatrikē, Psychiatriki
https://www.readbyqxmd.com/read/28540820/theoretical-model-for-laser-ablation-outcome-predictions-in-brain-calibration-and-validation-on-clinical-mr-thermometry-images
#3
Samuel John Fahrenholtz, Reza Madankan, Shabbar Danish, John D Hazle, R Jason Stafford, David Fuentes
PURPOSE: Neurosurgical laser ablation is experiencing a renaissance. Computational tools for ablation planning aim to further improve the intervention. Here, global optimisation and inverse problems are demonstrated to train a model that predicts maximum laser ablation extent. METHODS: A closed-form steady state model is trained on and then subsequently compared to N = 20 retrospective clinical MR thermometry datasets. Dice similarity coefficient (DSC) is calculated to provide a measure of region overlap between the 57 °C isotherms of the thermometry data and the model-predicted ablation regions; 57 °C is a tissue death surrogate at thermal steady state...
May 19, 2017: International Journal of Hyperthermia
https://www.readbyqxmd.com/read/28533954/exercise-and-dietary-program-induced-weight-reduction-is-associated-with-cognitive-function-among-obese-adolescents-a-longitudinal-study
#4
Chun Xie, Xiaochun Wang, Chenglin Zhou, Chang Xu, Yu-Kai Chang
OBJECTIVE: The present study was to determine the effect of a combined exercise and dietary program on cognitive function as well as the relationship between the program-induced weight change and cognitive function alterations. DESIGN: The study applies a quasi-experimental design. METHODS: Fifty-eight adolescents with obese status (body mass index, BMI >28 kg/m(2)) were assigned to either an experiment (n = 30) or control group (n = 28)...
2017: PeerJ
https://www.readbyqxmd.com/read/28522658/effect-of-fontan-geometry-on-exercise-haemodynamics-and-its-potential-implications
#5
Elaine Tang, Zhenglun Alan Wei, Kevin K Whitehead, Reza H Khiabani, Maria Restrepo, Lucia Mirabella, James Bethel, Stephen M Paridon, Bradley S Marino, Mark A Fogel, Ajit P Yoganathan
OBJECTIVE: Exercise intolerance afflicts Fontan patients with total cavopulmonary connections (TCPCs) causing a reduction in quality of life. Optimising TCPC design is hypothesised to have a beneficial effect on exercise capacity. This study investigates relationships between TCPC geometries and exercise haemodynamics and performance. METHODS: This study included 47 patients who completed metabolic exercise stress test with cardiac magnetic resonance (CMR). Phase-contrast CMR images were acquired immediately following supine lower limb exercise...
May 18, 2017: Heart: Official Journal of the British Cardiac Society
https://www.readbyqxmd.com/read/28521759/dosimetric-comparison-of-interstitial-brachytherapy-with-multi-channel-vaginal-cylinder-plans-in-patients-with-vaginal-tumors
#6
Lucas C Mendez, Moti Paudel, Matt Wronski, Ananth Ravi, Lisa Barbera, Eric Leung
BACKGROUND: To evaluate the dosimetric performance of multi-channel vaginal cylinder (MCVC) against interstitial brachytherapy (ISBT) for the treatment of vaginal tumors. METHODS: Vaginal tumors with extension of > 0.5 cm and ≤ 2 cm from the lateral vaginal wall and/or ≤ 1 cm in height above the vaginal vault were retrospectively selected from a ISBT registry trial database. The selected patients were treated with ISBT and targets included the intermediate (IRCTV) or high-risk (HRCTV) clinical target volumes...
May 18, 2017: Radiation Oncology
https://www.readbyqxmd.com/read/28513902/prospective-analysis-of-radiation-oncology-image-and-plan-driven-peer-review-for-head-and-neck-cancer
#7
Sakellarios Zairis, Danielle N Margalit, Trevor J Royce, William D Powlis, Roy B Tishler, Jonathan D Schoenfeld
BACKGROUND: Departmental "chart rounds" is an established form of review in radiation oncology, however, evidence is lacking that identifies links between features of a more subspecialized disease site-specific review and the likelihood and characteristics of recommendations made. We prospectively analyzed our head and neck group's review process to identify associations that could guide future practice. METHODS: Our group reviewed proposed management and treatment volumes for radiation simulated patients on a weekly basis, and we collected data encompassing recommendations made by individuals or group consensus...
May 17, 2017: Head & Neck
https://www.readbyqxmd.com/read/28508307/duration-of-antiviral-prophylaxis-and-risk-of-herpes-zoster-among-patients-receiving-autologous-hematopoietic-stem-cell-transplants-a-retrospective-observational-study
#8
Dongmu Zhang, Thomas Weiss, Yu Feng, Lynn Finelli
INTRODUCTION: There are no real-world data on antiviral prophylaxis (AP) duration and risk of herpes zoster (HZ) given AP duration in patients receiving autologous hematopoietic stem cell transplants (auto-HSCT). The objectives of this study are to describe the duration of AP and to compare incidence of HZ by AP duration in auto-HSCT patients. METHODS: This is a retrospective, observational database (Marketscan(®)) study. This study included patients ≥18 years old who had auto-HSCT during 2009-2013, had chemotherapy within 60 days prior to auto-HSCT (latest chemotherapy date within the 60 days was the study enrollment date), and had continuous health plan enrollment for at least 365 days before and after the study enrollment date...
May 15, 2017: Advances in Therapy
https://www.readbyqxmd.com/read/28506229/determinants-of-felt-demand-for-dengue-vaccines-in-the-north-caribbean-region-of-colombia
#9
Yalil T Bracho-Churio, Ruth A Martínez-Vega, Alfonso J Rodriguez-Morales, Ronald G Díaz-Quijano, María L Luna-González, Fredi A Diaz-Quijano
BACKGROUND: The increasing burden associated with dengue in Latin America makes it essential to understand the community's interest in acquiring vaccines, as an input to plan its introduction in endemic regions. The objective of this study is to learn the felt demand for dengue vaccines by estimating the willingness to pay and its associated factors in endemic communities of the North Caribbean region of Colombia. METHODS: A population survey was administered from October to December 2015, including 1037 families in 11 municipalities in Colombia...
May 15, 2017: Annals of Clinical Microbiology and Antimicrobials
https://www.readbyqxmd.com/read/28502472/a-novel-concept-for-tumour-targeting-with-radiation-inverse-dose-painting-or-targeting-the-low-drug-uptake-volume
#10
Ala Yaromina, Marlies Granzier, Rianne Biemans, Natasja Lieuwes, Wouter van Elmpt, Georgy Shakirin, Ludwig Dubois, Philippe Lambin
BACKGROUND AND PURPOSE: We tested a novel treatment approach combining (1) targeting radioresistant hypoxic tumour cells with the hypoxia-activated prodrug TH-302 and (2) inverse radiation dose-painting to boost selectively non-hypoxic tumour sub-volumes having no/low drug uptake. MATERIAL AND METHODS: (18)F-HX4 hypoxia tracer uptake measured with a clinical PET/CT scanner was used as a surrogate of TH-302 activity in rhabdomyosarcomas growing in immunocompetent rats...
May 11, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28498612/design-of-a-modulated-orthovoltage-stereotactic-radiosurgery-system
#11
Jessica M Fagerstrom, Edward T Bender, Michael J Lawless, Wesley S Culberson
PURPOSE: To achieve stereotactic radiosurgery (SRS) dose distributions with sharp gradients using orthovoltage energy fluence modulation with inverse planning optimization techniques. METHODS: A pencil beam model was used to calculate dose distributions from an orthovoltage unit at 250 kVp. Kernels for the model were derived using Monte Carlo methods. A Genetic Algorithm search heuristic was used to optimize the spatial distribution of added tungsten filtration to achieve dose distributions with sharp dose gradients...
May 12, 2017: Medical Physics
https://www.readbyqxmd.com/read/28486591/hourglass-like-constriction-of-the-brachial-plexus-in-the-posterior-cord-a-case-report
#12
Yasunobu Nakagawa, Hitoshi Hirata
BACKGROUND AND IMPORTANCE: Hourglass-like constrictions are fascicular conditions confirmed definitively by interfascicular neurolysis. Certain peripheral nerves have vulnerable areas such as around the elbow in the posterior interosseous nerve. We report the first hourglass-like constriction in the brachial plexus supplying the radial innervated forearm musculature. Preoperative magnetic resonance imaging (MRI) findings of the brachial plexus were consistent with neuralgic amyotrophy (NA)...
May 9, 2017: Neurosurgery
https://www.readbyqxmd.com/read/28481175/dosimetric-evaluation-of-a-flexible-dual-balloon-constructed-applicator-in-treating-anorectal-cancer
#13
Hsiang-Chi Kuo, Keyur J Mehta, Ravindra Yaparpalvi, Alan Lee, Dinesh Mynampati, William Bodner, Madhur Garg, David Huang, Wolfgang A Tomé, Shalom Kalnicki
BACKGROUND AND PURPOSE: To assess the dosimetric flexibility of a dual balloon brachytherapy applicator developed for the treatment of anorectal lesions. MATERIALS AND METHODS: Different amounts of water were infused into the inner and outer balloon separately to study the asymmetrical distribution of the catheter, the radial distance of the active source channel to the inner surface of the global target volume , the space between the active source channels, and their dosimetric impact to target tissues and uninvolved rectum...
January 1, 2017: Technology in Cancer Research & Treatment
https://www.readbyqxmd.com/read/28479790/value-of-minimum-apparent-diffusion-coefficient-on-magnetic-resonance-imaging-as-a-biomarker-for-predicting-progression-of-disease-following-surgery-and-radiotherapy-in-glial-tumors-from-a-tertiary-care-center-in-northern-india
#14
Pramod Kumar Gupta, Rishi Awasthi, Shalini Singh, Sanjay Behari, K J Maria Das, Rakesh Kumar Gupta, Shaleen Kumar
PURPOSE: Studies have shown that cellularity of glial tumors are inversely correlated to minimum apparent diffusion coefficient (ADC) values derived on diffusion-weighted imaging (DWI). The purpose of this prospective exploratory study was to evaluate whether temporal change in "minimum ADC" values during follow-up predict progressive disease in glial tumors post radiotherapy and surgery. MATERIALS AND METHODS: Adult patients of glial tumors, subjected to surgery followed by Radiotherapy (RT), were included in the study...
April 2017: Journal of Neurosciences in Rural Practice
https://www.readbyqxmd.com/read/28467321/simultaneous-optimization-of-photons-and-electrons-for-mixed-beam-radiotherapy
#15
Silvan Mueller, Michael Fix, Andreas Joosten, Dominik Henzen, Daniel Frei, Werner Volken, Reto Kueng, Daniel Aebersold, Marco Stampanoni, Peter Manser
The aim of this work is to develop and investigate an inverse treatment planning process (TPP) for mixed beam radiotherapy (MBRT) capable of performing simultaneous optimization of photon and electron apertures. A simulated annealing based direct aperture optimization (DAO) is implemented to perform simultaneous optimization of photon and electron apertures, both shaped with the photon multileaf collimator (pMLC). Validated beam models are used as input for Monte Carlo dose calculations. Consideration of photon pMLC transmission during DAO and a weight re-optimization of the apertures after deliverable dose calculation are utilized to efficiently reduce the differences between optimized and deliverable dose distributions...
May 3, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28462689/intensity-modulated-radiation-therapy-improves-the-target-coverage-over-3-d-planning-while-meeting-lung-tolerance-doses-for-all-patients-with-malignant-pleural-mesothelioma
#16
Sukran Ulger, Eren Cetin, Serap Catli, Hilal Sarac, Diclehan Kilic, Huseyin Bora
PURPOSE: To investigate high conformality on target coverage and the ability on creating strict lung dose limitation of intensity-modulated radiation therapy in malignant pleural mesothelioma. PATIENTS AND METHODS: Twenty-four radiation therapy plannings were evaluated and compared with dosimetric outcomes of conformal radiation therapy and intensity-modulated radiation therapy. Hemithoracal radiation therapy was performed on 12 patients with a fraction of 1.8 Gy to a total dose of 50...
June 2017: Technology in Cancer Research & Treatment
https://www.readbyqxmd.com/read/28461787/dosimetric-impact-in-the-dose-volume-histograms-of-rectal-and-vesical-wall-contouring-in-prostate-cancer-imrt-treatments
#17
Laura Gómez, Carlos Andrés, Antonio Ruiz
AIM: The main purpose of this study was to evaluate the differences in dose-volume histograms of IMRT treatments for prostate cancer based on the delineation of the main organs at risk (rectum and bladder) as solid organs or by contouring their wall. BACKGROUND: Rectum and bladder have typically been delineated as solid organs, including the waste material, which, in practice, can lead to an erroneous assessment of the risk of adverse effects. MATERIALS AND METHODS: A retrospective study was made on 25 patients treated with IMRT radiotherapy for prostate adenocarcinoma...
May 2017: Reports of Practical Oncology and Radiotherapy
https://www.readbyqxmd.com/read/28447959/using-measurable-dosimetric-quantities-to-characterize-the-inter-structural-tradeoff-in-inverse-planning
#18
Hongcheng Liu, Peng Dong, Lei Xing
Traditional inverse planning relies on the use of weighting factors to balance the conflicting requirements of different structures. The manual trial-and-error determination of the weighting factors has long been recognized as a time-consuming part of treatment planning. The purpose of this work is to develop an inverse planning framework that parameterizes the dosimetric tradeoff among the structures with physically meaningful quantities to simplify the search for clinically sensible plans. In this formalism, instead of using the weighting factors, permissible variation range of the prescription dose or dose volume histogram (DVH) of the involved structures are used to characterize the "importance" of the structures...
April 27, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28438215/predicting-liver-sbrt-eligibility-and-plan-quality-for-vmat-and-4%C3%AF-plans
#19
Angelia Tran, Kaley Woods, Dan Nguyen, Victoria Y Yu, Tianye Niu, Minsong Cao, Percy Lee, Ke Sheng
BACKGROUND: It is useful to predict planned dosimetry and determine the eligibility of a liver cancer patient for SBRT treatment using knowledge based planning (KBP). We compare the predictive accuracy using the overlap volume histogram (OVH) and statistical voxel dose learning (SVDL) KBP prediction models for coplanar VMAT to non-coplanar 4π radiotherapy plans. METHODS: In this study, 21 liver SBRT cases were selected, which were initially treated using coplanar VMAT plans...
April 24, 2017: Radiation Oncology
https://www.readbyqxmd.com/read/28433524/an-analysis-of-knowledge-based-planning-for-stereotactic-body-radiation-therapy-of-the-spine
#20
Joseph J Foy, Robin Marsh, Randall K Ten Haken, Kelly C Younge, Matthew Schipper, Yilun Sun, Dawn Owen, Martha M Matuszak
PURPOSE: Planning for spine stereotactic body radiation therapy (SBRT) is time consuming, and differences in planner experience and technique result in discrepancies in plan quality between facilities. Here, knowledge-based planning is analyzed to determine if it may be effective in improving the quality and efficiency of spine SBRT planning. MATERIALS AND METHODS: Thirty-eight spine SBRT cases were collected from the University of Michigan database and inverse planned to deliver 3 10-Gy fractions to the planning target volume (PTV)...
March 2, 2017: Practical Radiation Oncology
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"