Statistical analysis of dose-volume and dose-wall histograms for rectal toxicity following 3D-CRT in prostate cancer.

abstract：:Magnetic resonance images can be compromised by constant frequency (CF) noise, such as radio frequency (RF) noise. We investigate the effects of CF noise in four imaging methods with non-uniform k-space sampling: single-shot echo-planar imaging (EPI) with sinusoidal readout gradients, phase-encoded echo-planar spectro...

journal_title：Medical physics

authors： Du W,Karczmar GS,Pan X

更新日期：2002-08-01 00:00:00

abstract：:We report our experimental results of measurements of x-ray attenuation coefficients of aqueous solutions of a light absorbing dye, indocyanine green, and an immunoadjuvant, glycated chitosan. In the treatment of metastatic tumors in rats using a novel laser immunotherapy these solutions were administered in situ. The...

journal_title：Medical physics

authors： Xu F,Liu H,Wu X,Jiang H,Nordquist RE,Chen WR

更新日期：1999-07-01 00:00:00

abstract：PURPOSE:Hip fracture is a serious health problem and textural methods are being developed to assess bone quality. The authors aimed to perform textural analysis at femur on high-resolution digital radiographs compared to three-dimensional (3D) microarchitecture comparatively to bone mineral density. METHODS:Sixteen ca...

journal_title：Medical physics

authors： Ranjanomennahary P,Ghalila SS,Malouche D,Marchadier A,Rachidi M,Benhamou C,Chappard C

更新日期：2011-01-01 00:00:00

abstract：PURPOSE:The most appropriate method of evaluating the effective atomic number necessitates consideration of energy-dependent behavior. Previously, this required quite laborious calculation, which is why many scientists revert to over-simplistic power-law methods. The purpose of this work is to develop user-friendly sof...

journal_title：Medical physics

authors： Taylor ML,Smith RL,Dossing F,Franich RD

更新日期：2012-04-01 00:00:00

abstract：:The purposes of this study are: (i) to design field flattening filters for the Leipzig applicators of 2 and 3 cm of inner diameter with the source traveling parallel to the applicator contact surface, which are accessories of the microSelectron-HDR afterloader (Nucletron, Veenendaal, The Netherlands). These filters, m...

journal_title：Medical physics

authors： Granero D,Pérez-Calatayud J,Gimeno J,Ballester F,Casal E,Crispín V,van der Laarse R

更新日期：2008-02-01 00:00:00

abstract：PURPOSE:To provide specific experience-based guidance and recommendations for centers wishing to develop, validate, and implement an accurate and efficient process for directly using positron emission tomography-computed tomography (PET-CT) for the radiotherapy planning of head and neck cancer patients. METHODS:A PET-...

journal_title：Medical physics

authors： Thomas CM,Pike LC,Hartill CE,Baker S,Woods E,Convery DJ,Greener AG

更新日期：2014-04-01 00:00:00

abstract：:Proton NMR spectroscopy was applied to quantitate the measurement of total body water/fat distributions in vivo. A special MR protocol was developed to excite a thick slab of tissue and display the magnitude NMR spectrum of the collected response signal. Very short echo time TE (8 ms) and long repetition time TR (4000...

journal_title：Medical physics

authors： Sobol WT,Elster AD,Hinson WH,Chwals WJ

更新日期：1992-01-01 00:00:00

abstract：:A new variety of tissue-mimicking materials for use in 1H nuclear magnetic resonance (NMR) phantoms has been developed and extensively tested, principally at 10 MHz and at room temperature. The materials can be formed with a broad range of T1's and T2's representative of soft tissues. They are mixtures of various perc...

journal_title：Medical physics

authors： Blechinger JC,Madsen EL,Frank GR

更新日期：1988-07-01 00:00:00

abstract：:Boron neutron capture therapy (BNCT) is an experimental type of radiotherapy, presently being used to treat glioblastoma and melanoma. To improve patient safety and to determine the radiobiological characteristics of the epithermal neutron beam of Finnish BNCT facility (FiR 1) dose-response studies were carried on the...

journal_title：Medical physics

authors： Seppälä T,Auterinen I,Aschan C,Serén T,Benczik J,Snellman M,Huiskamp R,Ramadan UA,Kankaanranta L,Joensuu H,Savolainen S

更新日期：2002-11-01 00:00:00

abstract：PURPOSE:A new technique called "curvilinear approach" for prostate seed implantation has been proposed. The purpose of this study is to evaluate the dosimetric benefit of curvilinear distribution of seeds for low-dose-rate (LDR) prostate brachytherapy. METHODS:Twenty LDR prostate brachytherapy cases planned intraopera...

journal_title：Medical physics

authors： Podder TK,Dicker AP,Hutapea P,Darvish K,Yu Y

更新日期：2012-04-01 00:00:00

abstract：PURPOSE:This study aims to investigate the prompt secondary gamma spectrum and thedepth-dose distributions of incident 40 MeV protons onto various phantom materials.The goal is to find a relationship between the secondary prompt gamma emissions andthe range of the incident particles. METHODS:An application was constru...

journal_title：Medical physics

authors： Lau A,Chen Y,Ahmad S

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:In the context of fluorescence diffuse optical tomography, determining the optimal way to exploit the time-resolved information has been receiving much attention and different features of the time-resolved signals have been introduced. In this article, the authors revisit and generalize the notion of feature, c...

journal_title：Medical physics

authors： Ducros N,Da Silva A,Dinten JM,Seelamantula CS,Unser M,Peyrin F

更新日期：2010-06-01 00:00:00

abstract：:The authors are investigating the concept of a direct-conversion flat-panel imager with avalanche gain for low-dose x-ray imaging. It consists of an amorphous selenium (a-Se) photoconductor partitioned into a thick drift region for x-ray-to-charge conversion and a relatively thin region called high-gain avalanche rush...

journal_title：Medical physics

authors： Wronski MM,Rowlands JA

更新日期：2008-12-01 00:00:00

abstract：:Available deformable registration methods are often inaccurate over large organ variation encountered, for example, in the rectum and bladder. The authors developed a novel approach to accurately and effectively register large deformations in the prostate region for adaptive radiation therapy. A software tool combinin...

journal_title：Medical physics

authors： Godley A,Ahunbay E,Peng C,Li XA

更新日期：2009-04-01 00:00:00

abstract：:A new system of radiation dose mapping based on laser heating of thermoluminescent dosimetric plates (TLDP) has been developed. Application of this technique to intraoperative radiotherapy (IORT) has been investigated. Preliminary results show that TLDP are a possible alternative to radiological films and ionization c...

journal_title：Medical physics

authors： Beteille D,Setzkom R,Prévost H,Dusseau L,Fesquet J,Gasiot J,Muraro S,Delard R,Dubois JB,Ailleres N,Missous O

更新日期：1996-08-01 00:00:00

abstract：PURPOSE:A compact, three-tesla magnetic resonance imaging (MRI) system has been developed. It features a 37 cm patient aperture, allowing the use of commercial receiver coils. Its design allows simultaneously for gradient amplitudes of 85 millitesla per meter (mT/m) sustained and 700 tesla per meter per second (T/m/s) ...

journal_title：Medical physics

authors： Weavers PT,Shu Y,Tao S,Huston J 3rd,Lee SK,Graziani D,Mathieu JB,Trzasko JD,Foo TK,Bernstein MA

更新日期：2016-03-01 00:00:00

abstract：PURPOSE:To compare beam characteristics of superficial X-rays with 6 MeV Electrons for the purpose of replacing superficial treatments with electron fields for skin lesions. METHODS:Electron beam cutouts were made with 12mm thickness cerrobend in diameters 2-5 cm to match superficial X-ray machine cones. Central axis ...

journal_title：Medical physics

authors： Avadhani J,Sasidharan S,Carton C,Lowen M,Klapproth T,Licitra C

更新日期：2012-06-01 00:00:00

abstract：:The head-scatter factors H were examined for four different linear accelerators and were found to be similar at field sizes larger than 3 x 3 cm2. Sharply reduced values for small collimator openings were observed for all the accelerators. It is concluded that the head-scatter (or collimator-scatter) factor has two ma...

journal_title：Medical physics

authors： Zhu TC,Bjärngard BE

更新日期：1994-01-01 00:00:00

abstract：PURPOSE:The possible clinical applications which can be performed using a newly developed detector depend on the detector's characteristic performance in a number of metrics including the dynamic range, resolution, uniformity, and stability. The authors have evaluated a prototype energy resolved fast photon counting x-...

journal_title：Medical physics

authors： Cho HM,Barber WC,Ding H,Iwanczyk JS,Molloi S

更新日期：2014-09-01 00:00:00

abstract：:The BrachySeed model LS-1 is one of the latest in a series of new brachytherapy 125I seeds that have recently become available commercially for interstitial implants. The dosimetric properties of the seed were investigated analytically, experimentally, and by Monte Carlo simulation. Following the AAPM Task Group 43 fo...

journal_title：Medical physics

authors： Chan GH,Prestwich WV

更新日期：2002-02-01 00:00:00

abstract：PURPOSE:The Nakagami statistical model and Nakagami shape parameter m have been widely used in linear tissue characterization and preliminarily characterized the envelope distributions of nonlinear encapsulated microbubbles (EMBs). However, the Nakagami distribution of nonlinear scattering EMBs lacked a systematical in...

journal_title：Medical physics

authors： Wang D,Sang Y,Zhang X,Hu H,Lu S,Zhang Y,Fu C,Cloutier G,Wan M

更新日期：2019-12-01 00:00:00

abstract：:Because of complex dose distributions and dose gradients that are created in three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiation therapy (IMRT), photon- and electron-energy spectra might change significantly with spatial locations and doses. This study examined variations in photon- and...

journal_title：Medical physics

authors： Jang SY,Liu HH,Mohan R,Siebers JV

更新日期：2007-04-01 00:00:00

abstract：PURPOSE:Patient-specific IMRT QA measurements are important components of processes designed to identify discrepancies between calculated and delivered radiation doses. Discrepancy tolerance limits are neither well defined nor consistently applied across centers. The AAPM TG-218 report provides a comprehensive review a...

journal_title：Medical physics

authors： Miften M,Olch A,Mihailidis D,Moran J,Pawlicki T,Molineu A,Li H,Wijesooriya K,Shi J,Xia P,Papanikolaou N,Low DA

更新日期：2018-04-01 00:00:00

abstract：:It is shown that predictions can be made of scatter-to-primary ratios for a variety of mammographic configurations. The different configurations can be produced by changes in source-detector distance; source-phantom distance; air gap; photon energy; phantom composition, thickness, and cross-sectional area. A detailed ...

journal_title：Medical physics

authors： Bernstein H,Muntz EP

更新日期：1986-11-01 00:00:00

abstract：PURPOSE:This study aims to measure the surface dose on an anthropomorphic phantom for intensity-modulated radiation therapy (IMRT) plans treated in a 1.5 T magnetic resonance (MR)-Linac. Previous studies have used Monte Carlo programs to simulate surface dose and have recognized high surface dose as a potential limitin...

journal_title：Medical physics

authors： Lim-Reinders S,Keller BM,Sahgal A,Chugh B,Kim A

更新日期：2020-07-01 00:00:00

abstract：PURPOSE:To improve image quality and reduce imaging dose in CBCT for radiation therapy applications and to realize near real-time image reconstruction based on use of a fast convergence iterative algorithm and acceleration by multi-GPUs. METHODS:An iterative image reconstruction that sought to minimize a weighted leas...

journal_title：Medical physics

authors： Xu Q,Yang D,Tan J,Anastasio M

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:Megavoltage grid therapy is currently delivered with step-and-shoot multisegment techniques or using a high attenuation block with divergent holes. However, the commercial availability of grid blocks is limited, their construction is difficult, and step-and-shoot techniques require longer treatment times and ar...

journal_title：Medical physics

authors： Almendral P,Mancha PJ,Roberto D

更新日期：2013-05-01 00:00:00

abstract：PURPOSE:The accuracy and precision of computed tomography (CT) pulmonary ventilation imaging with conventional CT scanners are limited by breathing variations. We propose a method to correct for the effect of breathing variations in CT ventilation imaging based on external respiratory signals acquired throughout a scan...

journal_title：Medical physics

authors： Yamamoto T,Kabus S

更新日期：2018-01-01 00:00:00

abstract：:For an effective radiotherapy the exact tumor location must be determined. The localization has to take into account patient's setup position as well as internal organ motion. Among the different localization methods, the use of a computer tomography (CT) scanner in the therapy room has been proposed recently. Achievi...

journal_title：Medical physics

authors： Vences L,Wulf J,Vordermark D,Sauer O,Berlinger K,Roth M

更新日期：2005-11-01 00:00:00

abstract：PURPOSE:Target localization accuracy of cone-beam CT (CBCT) images used in radiation treatment of respiratory disease sites is affected by motion artifacts (blurring and streaking). The authors have previously reported on a method of respiratory motion correction in thoracic CBCT at end expiration (EE). The previous re...

journal_title：Medical physics

authors： Dzyubak O,Kincaid R,Hertanto A,Hu YC,Pham H,Rimner A,Yorke E,Zhang Q,Mageras GS

更新日期：2014-10-01 00:00:00