Measurements of the neutron yields from 7Li(p,n)7Be reaction (thick target) with incident energies from 1.885 to 2.0 MeV.

abstract：PURPOSE:To study the relationships between dose (D), kerma (K), and collision kerma ( K col ) in photon beams and to investigate total radiative yields for electrons and positrons as a functio...

journal_title：Medical physics

authors： Rogers DWO,Townson RW

更新日期：2019-11-01 00:00:00

abstract：PURPOSE:Lower radiation tolerance of the whole liver hinders dose escalations of stereotactic body radiation therapy (SBRT) in hepatocellular carcinoma (HCC) treatment. This study was conducted to define the exact doses that result in radiation-induced liver disease (RILD) as well as to determine dose constraints for t...

journal_title：Medical physics

authors： Wu ZF,Zhang JY,Shen XY,Zhou LY,Gao YB,Hu Y,Zeng ZC

更新日期：2016-07-01 00:00:00

abstract：:A technique was developed to reduce the size and magnitude of the hot and cold spots in the abutting regions of photon and electron fields. The photon and electron fields were set up such that the photon field extended approximately 2 cm into the electron field in the abutting region. The region of the photon beam tha...

journal_title：Medical physics

authors： Li JG,Xing L,Boyer AL,Hamilton RJ,Spelbring DR,Turian JV

更新日期：1999-11-01 00:00:00

abstract：:It is well established that the diffusion approximation (DA) is valid for light propagation in highly scattering media, but it breaks down in nonscattering void regions. The methods that handle the void with refractive index matched boundary were previously developed. For the void with refractive index mismatched boun...

journal_title：Medical physics

authors： Lee JH,Kim S,Kim YT

更新日期：2004-08-01 00:00:00

abstract：:The aim of this study is to perform a statistical analysis to verify the calculated percentage depth dose (PDD) based on the tissue maximum ratio (TMR) with the PDD measurements taken in water. 6 and 15 MV photon beams produced by a Varian linear 2100 C/D accelerator were used. PDDs and TMRs were measured at various d...

journal_title：Medical physics

authors： Isa M,Iqbal K,Afzal M,Buzdar S,Chow J

更新日期：2012-07-01 00:00:00

abstract：:Using superior localization and immobilization methods, stereotactic radiosurgery is capable of delivering spheres of dose as small as a few millimetres in diameter to intracranial targets. For targets abutting critical structures, the most conformal treatments minimize adverse radiation side effects and it is importa...

journal_title：Medical physics

authors： Keller BM,Peressotti C,Pignol JP

更新日期：2008-07-01 00:00:00

abstract：:We investigated the utility of three manual planimetric methods to quantify carotid plaque volume. A single observer measured 15 individual plaques from 15 three-dimensional (3D) ultrasound (3D US) images of patients ten times each using three different planimetric approaches. Individual plaque volumes were measured (...

journal_title：Medical physics

authors： Landry A,Ainsworth C,Blake C,Spence JD,Fenster A

更新日期：2007-04-01 00:00:00

abstract：PURPOSE:Anomalous pixels may be defined as those pixels whose exposure response relationship is deviant from the typical, expected or calibrated response. A group of anomalous pixels may Result in visible correlated artifacts. Here we demonstrate an approach to identify anomalous pixels and correlated artifacts using f...

journal_title：Medical physics

authors： Dave J,Gingold E,Yorkston J,Bercha I,Goldman L,Walz-Flannigan A,Willis C

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:The image quality of dedicated cone beam breast CT (CBBCT) is limited by substantial scatter contamination, resulting in cupping artifacts and contrast-loss in reconstructed images. Such effects obscure the visibility of soft-tissue lesions and calcifications, which hinders breast cancer detection and diagnosis...

journal_title：Medical physics

authors： Shi L,Vedantham S,Karellas A,Zhu L

更新日期：2016-08-01 00:00:00

abstract：:We present a technique for semiautomated segmentation of human prostates using suprapubic ultrasound (US) images. In this approach, a speckle reducing anisotropic diffusion (SRAD) is applied to enhance the images and the instantaneous coefficient of variation (ICOV) is utilized for edge detection. Segmentation is acco...

journal_title：Medical physics

authors： Yu Y,Molloy JA,Acton ST

更新日期：2004-12-01 00:00:00

abstract：:Spread of invasive carcinoma throughout breast tissue is believed to occur at supramolecular levels, beyond the range of standard histopathology identification. Small angle x-ray scattering (SAXS) is capable of characterizing the structural properties of collagen and tissue found in the breast at the scale of tens to ...

journal_title：Medical physics

authors： Sidhu S,Siu KK,Falzon G,Hart SA,Foxe JG,Lewis RA

更新日期：2009-07-01 00:00:00

abstract：:Measurements of a 670-MeV/amu 20Ne beam at the Lawrence Berkeley Laboratory Bevalac heavy-ion accelerator with various thicknesses of water absorber were obtained with the BERKLET. The BERKLET, a simple three-stage solid-state telescope detector, has been described previously. This instrument measures the linear energ...

journal_title：Medical physics

authors： Llacer J,Schmidt JB,Tobias CA

更新日期：1990-03-01 00:00:00

abstract：PURPOSE:To measure the calibration curves of EBT3 dosimetry films in photon and proton beams and to quantify the related uncertainties from one beam type to another. METHODS:EBT3 Gafchromic films have similar properties than EBT2 with a symmetric construction and a matte polyester substrate to prevent Newton's ring ar...

journal_title：Medical physics

authors： Sorriaux J,Rossomme S,Kacperek A,Bertrand D,Vynckier S,Sterpin E

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:Within the European project ALLEGRO (grant agreement no. 231965), the out-of-field dose delivered to a patient when treated with different radiotherapy modalities was investigated. The study compared the dose distribution during photon and particle irradiations both in a water and an anthropomorphic phantom to ...

journal_title：Medical physics

authors： Kaderka R,Durante M,Berger T,Reitz G,Tessa C

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:There is interest in developing linac-MR systems for MRI-guided radiation therapy. To date, the designs for such linac-MR devices have been restricted to a transverse geometry where the static magnetic field is oriented perpendicular to the direction of the incident photon beam. This work extends possibilities ...

journal_title：Medical physics

authors： Kirkby C,Murray B,Rathee S,Fallone BG

更新日期：2010-09-01 00:00:00

abstract：:The dose distributions in the bifurcated vessels treated with intravascular brachytherapyline sources are complicated and depend on the bifurcation geometry consisting of a main and a branch vessel at different angles. To investigate the dosimetric effects at the bifurcation, calculations were performed on branching v...

journal_title：Medical physics

authors： Yue N,Roberts KB,Pfau SE,Nath R

更新日期：2003-07-01 00:00:00

abstract：:Attention is given to means of sensing ultrasonic energy distributions over an area. Under the restraints appropiate to real-time imaging of deep body organs, piezoelectric arrays offer the most promising method. Adaptation of integrated circuit techniques to array assembly permits very large arrays of small elements ...

journal_title：Medical physics

authors： Maginness MG,Plummer JD,Beaver WL,Meindl JD

更新日期：1976-09-01 00:00:00

abstract：PURPOSE:Recent advances in compressed sensing (CS) enable accurate CT image reconstruction from highly undersampled and noisy projection measurements, due to the sparsifiable feature of most CT images using total variation (TV). These novel reconstruction methods have demonstrated advantages in clinical applications wh...

journal_title：Medical physics

authors： Niu T,Zhu L

更新日期：2012-07-01 00:00:00

abstract：:Recently, the clinical application of electronic portal imaging devices has enabled more frequent verification of patient setup for radiation treatment. However, the image quality has sometimes proven to be inadequate, motivating the investigation of alternative sensors with better image quality. Amorphous selenium (a...

journal_title：Medical physics

authors： Mah D,Rowlands JA,Rawlinson JA

更新日期：1998-04-01 00:00:00

abstract：:Quantitation of planar radionuclide images is hampered by structures containing radioactivity which overlie or underlie the organ of interest. The introduction of single photon emission computerized tomography (SPECT) overcame this problem to a large extent and enhanced the contrast of the images. Attenuation of photo...

journal_title：Medical physics

authors： Pretorius PH,van Aswegen AI,Herbst CP,Lötter MG

更新日期：1991-05-01 00:00:00

abstract：PURPOSE:To identify which physical properties of nanoparticles are correlated with the survival fraction of cells exposed in vitro to low-energy protons in combination with nanoparticles. METHODS:The Geant4 simulation toolkit (version 10.3) was used to model nanoparticles of different sizes (5-50 nm) and materials (Ti...

journal_title：Medical physics

authors： Heuskin AC,Gallez B,Feron O,Martinive P,Michiels C,Lucas S

更新日期：2017-08-01 00:00:00

abstract：PURPOSE:To develop a probabilistic treatment planning (PTP) method which is robust to systematic patient setup errors and to compare PTP plans with plans generated using a planning target volume (PTV) margin optimized to give the same target coverage probability as the PTP plan. METHODS:Plans adhering to the RTOG-0126...

journal_title：Medical physics

authors： Moore JA,Gordon JJ,Anscher M,Silva J,Siebers JV

更新日期：2012-02-01 00:00:00

abstract：PURPOSE:To present a noninvasive technique for directly measuring the CT bow-tie filter attenuation with a linear array x-ray detector. METHODS:A scintillator based x-ray detector of 384 pixels, 307 mm active length, and fast data acquisition (model X-Scan 0.8c4-307, Detection Technology, FI-91100 Ii, Finland) was use...

journal_title：Medical physics

authors： Li X,Shi JQ,Zhang D,Singh S,Padole A,Otrakji A,Kalra MK,Xu XG,Liu B

更新日期：2015-11-01 00:00:00

abstract：PURPOSE:Brachytherapy is a treatment modality which delivers large doses of radiation in a reduced number of visits. Since a small number of large dose-per-fraction is administered in high dose rate brachytherapy, ensuring the right dose is delivered is highly critical. In this work, a scintillation detector is coupled...

journal_title：Medical physics

authors： Tho D,Beaulieu L

更新日期：2019-05-01 00:00:00

abstract：PURPOSE:Contrast-enhanced imaging of the breast is frequently used in breast MRI and has recently become more common in mammography. The purpose of this study was to make single-scan contrast-enhanced imaging feasible for photon-counting breast CT (pcBCT) and to assess the spectral performance of a pcBCT scanner by eva...

journal_title：Medical physics

authors： Ruth V,Kolditz D,Steiding C,Kalender WA

更新日期：2020-07-01 00:00:00

abstract：PURPOSE:To determine the diagnostic efficacy of optical coherence tomography (OCT) to identify cervical intraepithelial neoplasia (CIN) grade 2 or higher by computer-aided diagnosis (CADx). METHODS:OCT has been investigated as a screening/diagnostic tool in the management of preinvasive and early invasive cancers of t...

journal_title：Medical physics

authors： Kang W,Qi X,Tresser NJ,Kareta M,Belinson JL,Rollins AM

更新日期：2011-01-01 00:00:00

abstract：:Calibrated C-arm fluoroscopy is used for a variety of surgical procedures where surgical tools and anatomical structures need to be located in space. Calibration can be performed online by combining measurements of the geometry of the image (center and radius) with measurements of a grid of fiducial markers. This arti...

journal_title：Medical physics

authors： Archip N,Rohling R

更新日期：2004-09-01 00:00:00

abstract：:Some limitations of conventional two-dimensional computer programs used to plan radiation therapy are presented. These include: a lack of involvement in defining the clinical problem; deficiencies in the algorithms for computing dose; failure to compute dose throughout the volume of interest; an inability to handle tr...

journal_title：Medical physics

authors： Goitein M

更新日期：1982-07-01 00:00:00

abstract：PURPOSE:At our institution, all proton patient plans undergo patient-specific quality assurance (PSQA) prior to treatment delivery. For intensity-modulated proton beam therapy, quality assurance is complex and time consuming, and it may involve multiple measurements per field. We reviewed our PSQA workflow and identifi...

journal_title：Medical physics

authors： Hernandez Morales D,Shan J,Liu W,Augustine KE,Bues M,Davis MJ,Fatyga M,Johnson JE,Mundy DW,Shen J,Younkin JE,Stoker JB

更新日期：2019-01-01 00:00:00

abstract：PURPOSE:In this study the Octavius detector 729 ionization chamber (IC) array with the Octavius 4D phantom was characterized for flattening filter (FF) and flattening filter free (FFF) static and rotational beams. The device was assessed for verification with FF and FFF RapidArc treatment plans. METHODS:The response o...

journal_title：Medical physics

authors： McGarry CK,O'Connell BF,Grattan MW,Agnew CE,Irvine DM,Hounsell AR

更新日期：2013-09-01 00:00:00