Development of optical process for accessing three-dimensional patient topology.

abstract：PURPOSE:To implement the DMAIC (Define-Measure-Analyze-Improve-Control) can be used for customizing the patient-specific QA by designing site-specific range tolerances. METHODS:The DMAIC framework (process flow diagram, cause and effect, Pareto chart, control chart, and capability analysis) were utilized to determine ...

journal_title：Medical physics

authors： Rah JE,Shin D,Manger RP,Kim TH,Oh DH,Kim DY,Kim GY

更新日期：2018-02-01 00:00:00

abstract：:Single photon emission computed tomography (SPECT) is an important technology for molecular imaging studies of small animals. In this arena, there is an increasing demand for high performance imaging systems that offer improved spatial resolution and detection efficiency. We have designed a multipinhole small animal i...

journal_title：Medical physics

authors： Funk T,Després P,Barber WC,Shah KS,Hasegawa BH

更新日期：2006-05-01 00:00:00

abstract：PURPOSE:Scatter contamination in cone-beam computed tomography (CBCT) degrades the image quality by introducing shading artifacts. A moving-blocker-based approach has been proposed to simultaneously estimate scatter and reconstruct the complete volume within field of view (FOV) from a single CBCT scan. Promising result...

journal_title：Medical physics

authors： Ouyang L,Song K,Wang J

更新日期：2013-07-01 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: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：:A computer program was implemented to predict mammography x-ray beam parameters in the range 20-40 kV for Mo/Mo, Mo/Rh, Rh/Rh, and W/Al target/filter combinations. The computation method used to simulate mammography x-ray spectra is based on the Boone et al. model. The beam quality parameters such as the half-value la...

journal_title：Medical physics

authors： Kharrati H,Zarrad B

更新日期：2003-10-01 00:00:00

abstract：:In the case of non-small cell lung cancer, doses typically prescribed (60-66 Gy) are not sufficient to ensure a satisfactory tumor control probability. Dose escalation needs to be realized, but dose to organs at risk (OARs) must be kept under widely accepted clinical thresholds. Also, lung functionality is not homogen...

journal_title：Medical physics

authors： St-Hilaire J,Lavoie C,Beaulieu F,Dagnault A,Morin F,Gingras L,Tremblay D,Beaulieu L

更新日期：2008-07-01 00:00:00

abstract：:Monte Carlo simulations of x-ray beams typically take parameters of the electron beam in the accelerating waveguide to be free parameters. In this paper, a methodology is proposed and implemented to determine the energy, spectral width, and beam divergence of the electron source. All treatment head components were rem...

journal_title：Medical physics

authors： Sawkey DL,Faddegon BA

更新日期：2009-03-01 00:00:00

abstract：:Secondary neutron ambient dose equivalents per the treatment absorbed dose in passive carbon-ion and proton radiotherapies were measured using a rem meter, WENDI-II at two carbon-ion radiotherapy facilities and four proton radiotherapy facilities in Japan. Our measured results showed that (1) neutron ambient dose equi...

journal_title：Medical physics

authors： Yonai S,Matsufuji N,Kanai T,Matsui Y,Matsushita K,Yamashita H,Numano M,Sakae T,Terunuma T,Nishio T,Kohno R,Akagi T

更新日期：2008-11-01 00:00:00

abstract：PURPOSE:To describe an efficient method for verifying the size and centering of the radiation field from the Cyberknife IRIS variable collimator with sub-millimeter accuracy using a general purpose commercially available diode array. METHODS:We present a technique using a conventional diode array (Sun Nuclear Profiler...

journal_title：Medical physics

authors： Gibbs G,White G,Bulz G

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:A practical detector structure is proposed to achieve stable avalanche multiplication gain in direct-conversion amorphous selenium radiation detectors. METHODS:The detector structure is referred to as a field-shaping multi-well avalanche detector. Stable avalanche multiplication gain is achieved by eliminating...

journal_title：Medical physics

authors： Goldan AH,Zhao W

更新日期：2013-01-01 00:00:00

abstract：PURPOSE:This study aims to investigate carotid plaque calcification (CPC) using two-dimensional (2D) and 3D ultrashort echo time (UTE) magnetic resonance imaging (MRI) sequences and compare T1, T2*, water concentration, and bone mineral density (BMD) of CPC with those of cortical bone. METHODS:Twelve carotid plaque sp...

journal_title：Medical physics

authors： Du J,Peterson M,Kansal N,Bydder GM,Kahn A

更新日期：2013-10-01 00:00:00

abstract：PURPOSE:This work is to evaluate the effects of Compton current generation in three small-volume ionization chambers on measured beam characteristics for electron fields. METHODS:Beam scans were performed using Exradin A16, A26, and PTW 31014 microchambers. Scans with varying chamber components shielded were performed...

journal_title：Medical physics

authors： Tanny S,Holmes S,Sperling N,Parsai EI

更新日期：2015-10-01 00:00:00

abstract：PURPOSE:Automated segmentation could improve the efficiency of modeling-based pelvic organ prolapse (POP) evaluations. However, segmentation performance is limited by the blurry soft tissue boundaries. In this study, we aimed to present a hybrid solution for uterus, rectum, bladder, and levator ani muscle segmentation ...

journal_title：Medical physics

authors： Feng F,Ashton-Miller JA,DeLancey JOL,Luo J

更新日期：2020-09-01 00:00:00

abstract：:Currently, patients with brain neoplasms must undergo both computed tomography (CT) and magnetic resonance (MR) imaging to take advantage of CT's density information and MR's soft tissue imaging capabilities. A method has been developed that allows virtual simulation, digitally reconstructed radiographs (DRRs), and 3-...

journal_title：Medical physics

authors： Ramsey CR,Oliver AL

更新日期：1998-10-01 00:00:00

abstract：PURPOSE:Particle therapy is becoming increasingly available world-wide for precise tumor targeting, its favorable depth dose deposition, and increased biological damage to tumor tissue compared to conventional photon therapy. As demand increases for improved robustness and conformality, next-generation secondary dose c...

journal_title：Medical physics

authors： Kopp B,Fuglsang Jensen M,Mein S,Hoffmann L,Nyström H,Falk M,Haberer T,Abdollahi A,Debus J,Mairani A

更新日期：2020-10-01 00:00:00

abstract：PURPOSE:For the purpose of size-specific dose estimation, information regarding patient attenuation is required. The purpose of this work is to describe a method for measuring patient attenuation and expressing the results in terms of a water cylinder, with cross sectional area A(w), which would absorb the same average...

journal_title：Medical physics

authors： Wang J,Duan X,Christner JA,Leng S,Yu L,McCollough CH

更新日期：2012-11-01 00:00:00

abstract：:The Gafchromic EBT was recently introduced in film dosimetry for external beam therapy (EBT). The high spatial resolution, weak energy dependence, and near-tissue equivalence of EBT films make them suitable for measurement of dose distributions in radiotherapy, especially intensity-modulated radiation therapy (IMRT). ...

journal_title：Medical physics

authors： Fiandra C,Ricardi U,Ragona R,Anglesio S,Giglioli FR,Calamia E,Lucio F

更新日期：2006-11-01 00:00:00

abstract：PURPOSE:To provide an overview of the types of adverse events reported to the US Food and Drug Administration (US FDA) for magnetic resonance (MR) systems over a 10-yr period. METHODS:Two reviewers independently reviewed adverse events reported to FDA for MR systems from 1 January 2008 to 31 December 2017 and manually...

journal_title：Medical physics

authors： Delfino JG,Krainak DM,Flesher SA,Miller DL

更新日期：2019-12-01 00:00:00

abstract：:Flat-panel (FP) based digital radiography systems have recently been introduced as a new and improved digital radiography technology; it is important to evaluate and compare this new technology with currently widely used conventional screen/film (SF) and computed radiography (CR) techniques. In this study, the low-con...

journal_title：Medical physics

authors： Rong XJ,Shaw CC,Liu X,Lemacks MR,Thompson SK

更新日期：2001-11-01 00:00:00

abstract：PURPOSE:In fluoroscopy-guided clinical procedures that involve tracking objects over long treatment times, there is a need for reducing the amount of imaging dose delivered to the patient and the operating staff. In this study, we introduce a feedback metric to minimize tube current while maintaining a targeting precis...

journal_title：Medical physics

authors： Siddique S,Fiume E,Jaffray D

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:A three-dimensional finite element analysis based canine heart model is introduced that would enable the assessment of cardiac function. METHODS:The three-dimensional canine heart model is based on the cardiac deformation and motion model obtained from the Cardiac Mechanics Research Group at UCSD. The canine h...

journal_title：Medical physics

authors： Chen H,Varghese T

更新日期：2010-11-01 00:00:00

abstract：PURPOSE:It is important for many quantitative brain studies to label meaningful anatomical regions in MR brain images. However, due to high complexity of brain structures and ambiguous boundaries between different anatomical regions, the anatomical labeling of MR brain images is still quite a challenging task. In many ...

journal_title：Medical physics

authors： Ma G,Gao Y,Wu G,Wu L,Shen D

更新日期：2016-02-01 00:00:00

abstract：PURPOSE:The automated segmentation of each lung and trachea in CT scans is commonly taken as a solved problem. Indeed, existing approaches may easily fail in the presence of some abnormalities caused by a disease, trauma, or previous surgery. For robustness, we present ALTIS (implementation is available at http://lids....

journal_title：Medical physics

authors： Sousa AM,Martins SB,Falcão AX,Reis F,Bagatin E,Irion K

更新日期：2019-11-01 00:00:00

abstract：PURPOSE:In current clinical practice, there is no integrated 3D ultrasound (3DUS) guidance system clinically available for breast brachytherapy. In this study, the authors present a novel robot-assisted 3DUS system for real-time planning and guidance of breast interstitial high dose rate (HDR) brachytherapy treatment. ...

journal_title：Medical physics

authors： Poulin E,Gardi L,Barker K,Montreuil J,Fenster A,Beaulieu L

更新日期：2015-12-01 00:00:00

abstract：:The commonly used Blunck and Leisegang electron energy-loss distribution falls off too rapidly with increasing energy loss. Also, for large thicknesses and/or low-Z media, where their distribution should approach Landau's, it normalizes to 0.92 rather than 1.0, it overestimates the number of very small energy-loss eve...

journal_title：Medical physics

authors： Weinhous MS,Nath R

更新日期：1984-05-01 00:00:00

abstract：PURPOSE:Magnetic particle imaging (MPI) is a relatively new method to image the spatial distribution of magnetic nanoparticle (MNP) tracers administered to the body with high spatial and temporal resolution using an inhomogeneous magnetic field. The spatial information of the MNP's is encoded using a field free point (...

journal_title：Medical physics

authors： Top CB,Güngör A,Ilbey S,Güven HE

更新日期：2019-04-01 00:00:00

abstract：:Cone beam transmission CT (CB-CT) improves SPECT imaging by providing high-quality attenuation maps for attenuation compensation and for correlated SPECT and CT imaging. The present work measures the detection nonuniformity for CB-CT implemented with a gamma camera, and applies nonuniformity corrections to make CB-CT ...

journal_title：Medical physics

authors： Manglos SH,Capone RB,Bassano DA

更新日期：1992-03-01 00:00:00

abstract：PURPOSE:Electronic portal imagers (EPIDs) with high detective quantum efficiencies (DQEs) are sought to facilitate the use of the megavoltage (MV) radiotherapy treatment beam for image guidance. Potential advantages include high quality (treatment) beam's eye view imaging, and improved cone-beam computed tomography (CB...

journal_title：Medical physics

authors： Star-Lack J,Shedlock D,Swahn D,Humber D,Wang A,Hirsh H,Zentai G,Sawkey D,Kruger I,Sun M,Abel E,Virshup G,Shin M,Fahrig R

更新日期：2015-09-01 00:00:00

abstract：PURPOSE:Prostate biopsy, performed using two-dimensional (2D) transrectal ultrasound (TRUS) guidance, is the clinical standard for a definitive diagnosis of prostate cancer. Histological analysis of the biopsies can reveal cancerous, noncancerous, or suspicious, possibly precancerous, tissue. During subsequent biopsy s...

journal_title：Medical physics

authors： Karnik VV,Fenster A,Bax J,Cool DW,Gardi L,Gyacskov I,Romagnoli C,Ward AD

更新日期：2010-02-01 00:00:00