Signal, noise power spectrum, and detective quantum efficiency of indirect-detection flat-panel imagers for diagnostic radiology.

abstract：PURPOSE:Colitis refers to inflammation of the inner lining of the colon that is frequently associated with infection and allergic reactions. In this paper, we propose deep convolutional neural networks methods for lesion-level colitis detection and a support vector machine (SVM) classifier for patient-level colitis dia...

journal_title：Medical physics

authors： Liu J,Wang D,Lu L,Wei Z,Kim L,Turkbey EB,Sahiner B,Petrick NA,Summers RM

更新日期：2017-09-01 00:00:00

abstract：PURPOSE:Cardiac motion is typically not accounted for during pretreatment imaging for central lung and mediastinal tumors. However, cardiac induced tumor motion averages 5.8 mm for esophageal tumors and 3-5 mm for some lung tumors, which can result in positioning errors. Our aim is to reduce both cardiac- and respirato...

journal_title：Medical physics

authors： Reynolds T,Shieh CC,Keall PJ,O'Brien RT

更新日期：2019-09-01 00:00:00

abstract：:Techniques have been developed for reducing motion blurring artifacts by using respiratory gated computed tomography (CT) in sinogram space and quantitatively evaluating the artifact reduction. A synthetic sinogram was built from multiple scans intercepting a respiratory gating window. A gated CT image was then recons...

journal_title：Medical physics

authors： Lu W,Parikh PJ,Hubenschmidt JP,Politte DG,Whiting BR,Bradley JD,Mutic S,Low DA

更新日期：2005-11-01 00:00:00

abstract：PURPOSE:To improve the performance of a computer-aided detection (CAD) system for mass detection by using four-view information in screening mammography. METHODS:The authors developed a four-view CAD system that emulates radiologists' reading by using the craniocaudal and mediolateral oblique views of the ipsilateral ...

journal_title：Medical physics

authors： Wei J,Chan HP,Zhou C,Wu YT,Sahiner B,Hadjiiski LM,Roubidoux MA,Helvie MA

更新日期：2011-04-01 00:00:00

abstract：PURPOSE:Experimental dosimetry of high-dose-rate (HDR) 192 Ir brachytherapy (BT) sources is complicated due to high dose and dose-rate gradients, and softening of photon energy spectrum with depth. A single crystal synthetic diamond detector microDiamond (PTW 60019, Freiburg, Germany) has a small active volume, high se...

journal_title：Medical physics

authors： Kaveckyte V,Malusek A,Benmakhlouf H,Alm Carlsson G,Carlsson Tedgren Å

更新日期：2018-01-01 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：PURPOSE:Wide bore CT scanners use extended field-of-view (eFOV) reconstruction algorithms to attempt to recreate tissue truncated due to large patient habitus. Radiation therapy planning systems rely on accurate CT numbers in order to correctly plan and calculate radiation dose. This study looks at the impact of eFOV r...

journal_title：Medical physics

authors： Cheung JP,Shugard E,Mistry N,Pouliot J,Chen J

更新日期：2019-02-01 00:00:00

abstract：PURPOSE:The cardiovascular system (CVS) regulation can be studied from a central viewpoint, through heart rate variability (HRV) data, and from a peripheral viewpoint, through laser Doppler flowmetry (LDF) signals. Both the central and peripheral CVSs are regulated by several interacting mechanisms, each having its own...

journal_title：Medical physics

authors： Humeau A,Buard B,Mahé G,Rousseau D,Chapeau-Blondeau F,Abraham P

更新日期：2010-12-01 00:00:00

abstract：:In many of brachytherapy procedures, a large amount of radioactive sources are used to deliver desired doses to the target volume. It is both the federal regulation recommendation (U.S. Nuclear Regulatory Commission, 10 CFR 35.432) and recommendations of the American Association of Physicists in Medicine (AAPM) [Kutch...

journal_title：Medical physics

authors： Yue NJ,Haffty BG,Yue J

更新日期：2007-06-01 00:00:00

abstract：PURPOSE:Computational models of microwave tissue ablation are widely used to guide the development of ablation devices, and are increasingly being used for the development of treatment planning and monitoring platforms. Knowledge of temperature-dependent dielectric properties of lung tissue is essential for accurate mo...

journal_title：Medical physics

authors： Sebek J,Bortel R,Prakash P

更新日期：2019-10-01 00:00:00

abstract：PURPOSE:The main objective of this work was to design a comprehensive dosimetry package that would keep all aspects of internal dose calculation within the framework of a single software environment and that would be applicable for a variety of dose calculation approaches. METHODS:Our MATLAB-based graphical user inter...

journal_title：Medical physics

authors： Grimes J,Uribe C,Celler A

更新日期：2013-07-01 00:00:00

abstract：PURPOSE:Compton camera imaging (CCI) systems are currently under investigation for radiotherapy dose reconstruction and verification. The ability of such a system to provide real-time images during dose delivery will be limited by the computational speed of the image reconstruction algorithm. In this work, the authors ...

journal_title：Medical physics

authors： Mundy DW,Herman MG

更新日期：2011-01-01 00:00:00

abstract：:Single photon emission computed tomography (SPECT) was investigated for imaging on-board radiation therapy machines in order to localize functional and molecular targets. A computer-simulated female NCAT phantom was positioned supine on a flat-top treatment couch. Twenty tumor locations were defined in the upper torso...

journal_title：Medical physics

authors： Roper J,Bowsher J,Yin FF

更新日期：2009-05-01 00:00:00

abstract：:Contemporary reconstruction methods employed for clinical helical cone-beam computed tomography (CT) are analytical (noniterative) but mathematically nonexact, i.e., the reconstructed image contains so called cone-beam artifacts, especially for higher cone angles. Besides cone artifacts, these methods also suffer from...

journal_title：Medical physics

authors： Sunnegårdh J,Danielsson PE

更新日期：2008-09-01 00:00:00

abstract：:A quality assurance protocol has been developed to assess the relative accuracy of computerized monitor unit calculations. Results from this testing reveal that errors (defined as the difference between the computer results and those obtained using a standard formula with manual calculation) in monitor unit calculator...

journal_title：Medical physics

authors： Dahl RA,McCullough EC,Mellenberg DE

更新日期：1990-01-01 00:00:00

abstract：:Positron emission tomography (PET) has shown an increase in both sensitivity and specificity over computed tomography (CT) in lung cancer. However, motion artifacts in the 18F fluorodioxydoglucose (FDG) PET images caused by respiration persists to be an important factor in degrading PET image quality and quantificatio...

journal_title：Medical physics

authors： Nehmeh SA,Erdi YE,Ling CC,Rosenzweig KE,Squire OD,Braban LE,Ford E,Sidhu K,Mageras GS,Larson SM,Humm JL

更新日期：2002-03-01 00:00:00

abstract：PURPOSE:The purpose of this study was to quantitatively characterize the fundamental aspects of image quality (IQ) associated with different computed tomography (CT) reconstruction algorithms, the resolution, noise texture, noise magnitude per dose, and use those data to devise a methodology to match IQ between differe...

journal_title：Medical physics

authors： Winslow J,Zhang Y,Samei E

更新日期：2017-11-01 00:00:00

abstract：:Two new liquid ionization chamber (LIC) designs, consisting of cylindrical and plane-parallel configurations, are presented. They are designed to be suitable for high-precision measurements of absorbed dose-to-water at dose rates and photon energies typical for LDR intermediate photon energy brachytherapy sources. The...

journal_title：Medical physics

authors： Wickman G,Johansson B,Bahar-Gogani J,Holmström T,Grindborg JE

更新日期：1998-06-01 00:00:00

abstract：PURPOSE:Modern clinical accelerators are capable of producing ion beams from protons up to neon. This work compares the depth dose distribution and corresponding dose averaged linear energy transfer (LET) distribution, which is related to the biological effectiveness, for different ion beams (¹H, ⁴He, ⁶Li, ⁸Be, ¹⁰B, ¹²...

journal_title：Medical physics

authors： Kantemiris I,Karaiskos P,Papagiannis P,Angelopoulos A

更新日期：2011-12-01 00:00:00

abstract：PURPOSE:Distortions in magnetic resonance imaging (MRI) compromise spatial fidelity, potentially impacting delineation and dose calculation. We characterized 2D and 3D large field of view (FOV), sequence-independent distortion at various positions in a 1.0 T high-field open MR simulator (MR-SIM) to implement correction...

journal_title：Medical physics

authors： Price RG,Kadbi M,Kim J,Balter J,Chetty IJ,Glide-Hurst CK

更新日期：2015-10-01 00:00:00

abstract：:An important point to consider in a brachytherapy dosimetry study is the phantom size involved in calculations or experimental measurements. As pointed out by Williamson [Med. Phys. 18, 776-786 (1991)] this topic has a relevant influence on final dosimetric results. Presently, one-dimensional (1-D) algorithms and newl...

journal_title：Medical physics

authors： Pérez-Calatayud J,Granero D,Ballester F

更新日期：2004-07-01 00:00:00

abstract：:The purpose of this study is to understand the effect of pitch on raw data interpolation in multislice spiral/helical computed tomography (CT) and provide guidelines for scanner design and protocol optimization. Multislice spiral CT is mainly characterized by the three parameters: the number of detector arrays, the de...

journal_title：Medical physics

authors： Wang G,Vannier MW

更新日期：1999-12-01 00:00:00

abstract：:Attenuation correction is an essential component of the long chain of data correction techniques required to achieve the full potential of quantitative positron emission tomography (PET) imaging. The development of combined PET/magnetic resonance imaging (MRI) systems mandated the widespread interest in developing nov...

journal_title：Medical physics

authors： Mehranian A,Arabi H,Zaidi H

更新日期：2016-03-01 00:00:00

abstract：:The dosimetry of 192Ir linear sources with a commercial treatment planning computer system has been evaluated. Reference dose rate data were selected from the literature and normalized in a manner consistent with our clinical and dosimetric terminology. The results of the computer calculations are compared to the refe...

journal_title：Medical physics

authors： Kline RW,Gillin MT,Grimm DF,Niroomand-Rad A

更新日期：1985-09-01 00:00:00

abstract：:Skeletal dosimetry based on microCT images of trabecular bone has recently been introduced to calculate the red bone marrow (RBM) and the bone surface cell (BSC) equivalent doses in human phantoms for external exposure to photons. In order to use the microCT images for skeletal dosimetry, spongiosa voxels in the skele...

journal_title：Medical physics

authors： Kramer R,Khoury HJ,Vieira JW,Robson Brown KA

更新日期：2009-11-01 00:00:00

abstract：PURPOSE:The application of compressed sensing (CS) technology in magnetic resonance imaging (MRI) is to accelerate the MRI scan speed by incoherent undersampling of k-space data and nonlinear iterative reconstruction of MRI images. This paper generalizes the existing rosette trajectories to configure the sampling patte...

journal_title：Medical physics

authors： Li Y,Yang R,Zhang C,Zhang J,Jia S,Zhou Z

更新日期：2015-09-01 00:00:00

abstract：PURPOSE:Although small animal image-guided radiotherapy (SA-IGRT) systems are used increasingly in preclinical research, tools for performing routine quality assurance (QA) have not been optimized and are not readily available. Robust, efficient, and reliable QA tools are needed to ensure the accuracy and reproducibili...

journal_title：Medical physics

authors： Anvari A,Poirier Y,Sawant A

更新日期：2018-07-01 00:00:00

abstract：:We adapted a small sodium iodide scintillation detector for rapid, in vivo localization of a lost brachytherapy seed. Using the detector, we were able to locate and remove an Ir-192 seed that was not visible to the unaided eye. ...

journal_title：Medical physics

authors： Woolfenden JM,Barber HB,Oleson JR,Wild WJ

更新日期：1984-07-01 00:00:00

abstract：PURPOSE:Results about the feasibility of a method for quasi real time in vivo dosimetry (IVD) at the isocenter point for volumetric modulated arc therapy (VMAT) are here reported. The method is based on correlations between the EPID signal and the dose on the beam central axis. Moreover, the γ-analysis of EPID images w...

journal_title：Medical physics

authors： Fidanzio A,Porcelli A,Azario L,Greco F,Cilla S,Grusio M,Balducci M,Valentini V,Piermattei A

更新日期：2014-06-01 00:00:00

abstract：:The dosimetry for radiocolloid therapy of cystic craniopharyngiomas is investigated. Analytical calculations based on the Loevinger and the Berger formulas for electrons and photons, respectively, are compared with Monte Carlo simulations. The role of the material of which the colloid introduced inside the craniophary...

journal_title：Medical physics

authors： Rojas EL,Al-Dweri FM,Lallena AM,Bodineau C,Galán P

更新日期：2003-09-01 00:00:00