abstract：PURPOSE:Obtaining an integral depth-dose (IDD) curve using a recently developed acrylic-disk radiation sensor (ADRS) is time-consuming because its single structure requires point-by-point measurements in a water phantom. The goal of this study was to verify the ability of a newly designed multilayer ADRS, composed of 2...

journal_title：Medical physics

authors： Son J,Shin D,Kim T,Park S,Rah JE

更新日期：2020-09-01 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：PURPOSE:Computer-aided diagnosis (CAD) systems assist in solving subjective diagnosis problems that typically rely on personal experience. A CAD system has been developed to differentiate malignant thyroid nodules from benign thyroid nodules in ultrasound images based on deep learning methods. The diagnostic performanc...

journal_title：Medical physics

authors： Sun C,Zhang Y,Chang Q,Liu T,Zhang S,Wang X,Guo Q,Yao J,Sun W,Niu L

更新日期：2020-09-01 00:00:00

abstract：PURPOSE:Computational models are widely used during the design and characterization of microwave ablation (MWA) devices, and have been proposed for pretreatment planning. Our objective was to assess three-dimensional (3D) transient temperature and ablation profiles predicted by MWA computational models with temperature...

journal_title：Medical physics

authors： Faridi P,Keselman P,Fallahi H,Prakash P

更新日期：2020-09-01 00:00:00

abstract：PURPOSE:The combination of nonhuman primates (NHPs) with the state-of-the-art molecular imaging technologies allows for within-subject longitudinal research aiming at gaining new insights into human normal and disease conditions and provides an ideal foundation for future translational studies of new diagnostic tools, ...

journal_title：Medical physics

authors： Xie T,Chen X,Zaidi H

更新日期：2020-09-01 00:00:00

abstract：PURPOSE:To validate a delivery quality assurance (DQA) protocol for tomotherapy based on the measurement of the leaf open times (LOTs). In addition, to show the correlation between the mean relative LOT discrepancy and the dose deviation in the planning target volume (PTV). MATERIALS AND METHODS:We used a LOT measurem...

journal_title：Medical physics

authors： Schopfer M,Bochud FO,Bourhis J,Moeckli R

更新日期：2020-09-01 00:00:00

abstract：PURPOSE:The aim of this paper was to investigate the relationship between the physical and subjective (observer) image quality metrics in digital chest radiography. METHODS:Five digital radiography systems, four with indirect flat panel detector and one with storage phosphor-based computed radiography system, were use...

journal_title：Medical physics

authors： Yalcin A,Olgar T,Sancak T,Atac GK,Akyar S

更新日期：2020-09-01 00:00:00

abstract：PURPOSE:To investigate the inconsistency of recent literature on the effect of magnetic field on the response of radiochromic films, we studied the influence of 0.35 T magnetic field on dosimetric response of EBT3 and EBT-XD GafchromicTM films. METHODS:Two different models of radiochromic films, EBT3 and EBT-XD, were ...

journal_title：Medical physics

authors： Darafsheh A,Hao Y,Maraghechi B,Cammin J,Reynoso FJ,Khan R

更新日期：2020-09-01 00:00:00

abstract：PURPOSE:In intensity-modulated proton therapy (IMPT), protons are used to deliver highly conformal dose distributions, targeting tumors, and sparing organs-at-risk. However, due to uncertainties in both patient setup and relative stopping power (RSP) calculation, margins are added to the treatment volume during treatme...

journal_title：Medical physics

authors： Harms J,Lei Y,Wang T,McDonald M,Ghavidel B,Stokes W,Curran WJ,Zhou J,Liu T,Yang X

更新日期：2020-09-01 00:00:00

abstract：PURPOSE:The GammaPod is a novel dedicated prone breast stereotactic radiosurgery (SRS) device recently developed at the University of Maryland Medical Center. This device utilizes multiple rotating Co-60 sources to create highly conformal dose distributions for breast treatments, including boosts, partial breast irradi...

journal_title：Medical physics

authors： Becker SJ,Culberson WS,Poirier Y,Mutaf Y,Niu Y,Nichols EM,Yi B

更新日期：2020-08-01 00:00:00

abstract：BACKGROUND AND PURPOSE:The purpose of this study is to develop a deep learning-based approach to simultaneously segment five pelvic organs including prostate, bladder, rectum, left and right femoral heads on cone-beam CT (CBCT), as required elements for prostate adaptive radiotherapy planning. MATERIALS AND METHODS:We...

journal_title：Medical physics

authors： Fu Y,Lei Y,Wang T,Tian S,Patel P,Jani AB,Curran WJ,Liu T,Yang X

更新日期：2020-08-01 00:00:00

abstract：PURPOSE:Elastography using computer tomography (CT) is a promising methodology that can provide patient-specific regional distributions of lung biomechanical properties. The purpose of this paper is to investigate the feasibility of performing elastography using simulated lower dose CT scans. METHODS:A cohort of eight...

journal_title：Medical physics

authors： Hasse K,Hsieh SS,O'Connell D,Stiehl B,Min Y,Neylon J,Low DA,Santhanam AP

更新日期：2020-08-01 00:00:00

abstract：PURPOSE:The purpose of this work was to examine the suitability of VIPARnd polymer gel-9.4 T magnetic resonance microimaging system for high spatial resolution dose distribution measurements. METHODS:The VIPARnd samples (3 cm in outside diameter and 12 cm in height) were exposed to ionizing radiation by using a linear...

journal_title：Medical physics

authors： Skorupa A,Woźnica A,Ciszek M,Staniszewski M,Kijonka M,Kozicki M,Woźniak B,Orlef A,Polański A,Boguszewicz Ł,Sokół M

更新日期：2020-08-01 00:00:00

abstract：PURPOSE:Motion compensated positron emission tomography (PET) imaging requires detecting and monitoring of patient body motion. We developed a semiautomatic list-mode method to track the three-dimensional (3D) motion of fiducial positron-emitting markers during PET imaging. METHODS:A previously developed motion tracki...

journal_title：Medical physics

authors： Chamberland MJP,deKemp RA,Xu T

更新日期：2020-08-01 00:00:00

abstract：PURPOSE:To investigate the dosimetric robustness of dynamically collimated proton therapy (DCPT) treatment plans delivered using a dynamic collimation system (DCS) with respect to random uncertainties in beam spot and collimator position as well as systematic offsets in the DCS mounting alignment. This work also demons...

journal_title：Medical physics

authors： Smith BR,Hyer DE,Culberson WS

更新日期：2020-08-01 00:00:00

abstract：PURPOSE:To demonstrate the feasibility of a three-plenoptic camera projection, scintillation-based dosimetry system for measuring three-dimensional (3D) dose distributions of static photon radiation fields. METHODS:Static x-ray photon beams were delivered to a cubic plastic scintillator volume embedded within acrylic ...

journal_title：Medical physics

authors： Rilling M,Allain G,Thibault S,Archambault L

更新日期：2020-08-01 00:00:00

abstract：PURPOSE:Multiple commercial, open-source, and academic software tools exist for objective quantification of lung density in computed tomography (CT) images. The purpose of this study was to evaluate the intersoftware reproducibility of CT lung density measurements. METHODS:Computed tomography images from 50 participan...

journal_title：Medical physics

authors： Kirby M,Hatt C,Obuchowski N,Humphries SM,Sieren J,Lynch DA,Fain SB,QIBA Lung Density Committee.

更新日期：2020-07-01 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:Urinary particles are particularly important parameters in clinical urinalysis, especially for the diagnosis of nephropathy. Therefore, it is highly important to precisely detect urinary particles in the clinical setting. However, artificial microscopy is subjective and time consuming, and various previous dete...

journal_title：Medical physics

authors： Li Q,Yu Z,Qi T,Zheng L,Qi S,He Z,Li S,Guan H

更新日期：2020-07-01 00:00:00

abstract：PURPOSE:When designing a collimation system for pencil beam spot scanning proton therapy, a decision must be made whether or not to rotate, or focus, the collimator to match beamlet deflection as a function of off-axis distance. If the collimator is not focused, the beamlet shape and fluence will vary as a function of ...

journal_title：Medical physics

authors： Geoghegan TJ,Nelson NP,Flynn RT,Hill PM,Rana S,Hyer DE

更新日期：2020-07-01 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:For cone-beam computed tomography (CBCT) systems, we propose a sphere phantom based method to estimate the full three-dimensional (3D) modulation transfer function (MTF). METHODS:The FDK reconstruction of CBCT system in a local region was modeled by a triple convolution operator. Afterward, we calculated the d...

journal_title：Medical physics

authors： Lee C,Song HD,Baek J

更新日期：2020-07-01 00:00:00

abstract：PURPOSE:Magnetic resonance imaging (MRI)-guided percutaneous cryotherapy of abdominal lesions, an established procedure, uses MRI to guide and monitor the cryoablation of lesions. Methods to precisely guide cryotherapy probes with a minimum amount of trial-and-error are yet to be established. To aid physicians in attai...

journal_title：Medical physics

authors： Shono N,Ninni B,King F,Kato T,Tokuda J,Fujimoto T,Tuncali K,Hata N

更新日期：2020-06-01 00:00:00

abstract：PURPOSE:One technical barrier to patient-specific computed tomography (CT) dosimetry has been the lack of computational tools for the automatic patient-specific multi-organ segmentation of CT images and rapid organ dose quantification. When previous CT images are available for the same body region of the patient, the a...

journal_title：Medical physics

authors： Peng Z,Fang X,Yan P,Shan H,Liu T,Pei X,Wang G,Liu B,Kalra MK,Xu XG

更新日期：2020-06-01 00:00:00

abstract：:Computer-aided diagnosis (CAD) has been a major field of research for the past few decades. CAD uses machine learning methods to analyze imaging and/or nonimaging patient data and makes assessment of the patient's condition, which can then be used to assist clinicians in their decision-making process. The recent succe...

journal_title：Medical physics

authors： Chan HP,Hadjiiski LM,Samala RK

更新日期：2020-06-01 00:00:00

abstract：PURPOSE:In photon radiotherapy, respiratory-induced target motion can be accounted for by internal target volumes (ITV) or mid-ventilation target volumes (midV) defined on the basis of four-dimensional computed tomography (4D-CT). Intrinsic limitations of these approaches can result in target volumes that are not repre...

journal_title：Medical physics

authors： Rabe M,Thieke C,Düsberg M,Neppl S,Gerum S,Reiner M,Nicolay NH,Schlemmer HP,Debus J,Dinkel J,Landry G,Parodi K,Belka C,Kurz C,Kamp F

更新日期：2020-04-01 00:00:00

abstract：PURPOSE:The purpose of this study was to investigate the impact of transverse magnetic fields on the dose response of a radiophotoluminescent glass dosimeter (RGD) in megavoltage photon beams. METHODS:The RGD relative response (i.e., RGD dose per absorbed dose to water at the midpoint of the detector in the absence of...

journal_title：Medical physics

authors： Ito S,Araki F,Ohno T

更新日期：2020-04-01 00:00:00

abstract：PURPOSE:To develop a novel three-dimensional (3D) hybrid-encoding framework using compressed sensing (CS) and Toeplitz encoding with variable phase-scrambled radio-frequency (RF) excitation, which has the following advantages: low power deposition of RF pulses, reduction of the signal dynamic range, no additional hardw...

journal_title：Medical physics

authors： Wang H,Liang D,Su S,King KF,Chang Y,Liu X,Zheng H,Ying L

更新日期：2020-04-01 00:00:00

abstract：PURPOSE:To use machine-learning algorithms and blur measure (BM) operators to automatically detect motion blur in mammograms. Motion blur has been reported to reduce lesion detection performance and mask small abnormalities, resulting in failure to detect them until they reach more advanced stages. Automatic detection ...

journal_title：Medical physics

authors： Kamona N,Loew M

更新日期：2020-04-01 00:00:00

abstract：BACKGROUND:X-ray dark-field radiography could enhance mammography by providing more information on imaged tissue and microcalcifications. The dark field signal is a measure of small angle scattering and can thus provide additional information on the imaged materials. This information can be useful for material distinct...

journal_title：Medical physics

authors： Rauch T,Rieger J,Pelzer G,Horn F,Erber R,Wunderle M,Emons J,Nabieva N,Fuhrich N,Michel T,Hartmann A,Fasching PA,Anton G

更新日期：2020-04-01 00:00:00

abstract：PURPOSE:Calculations of deoxyribonucleic acid (DNA) damages involve many parameters in the computation process. As these parameters are often subject to uncertainties, it is of central importance to comprehensively quantify their impacts on DNA single-strand break (SSB) and double-strand break (DSB) yields. This has be...

journal_title：Medical physics

authors： Lai Y,Tsai MY,Tian Z,Qin N,Yan C,Hung SH,Chi Y,Jia X

更新日期：2020-04-01 00:00:00

abstract：PURPOSE:Image guidance is crucial for percutaneous tumor ablations, enabling accurate needle-like applicator placement into target tumors while avoiding tissues that are sensitive to injury and/or correcting needle deflection. Although ultrasound (US) is widely used for image guidance, magnetic resonance (MR) is prefer...

journal_title：Medical physics

authors： Yamada A,Tokuda J,Naka S,Murakami K,Tani T,Morikawa S

更新日期：2020-03-01 00:00:00

abstract：PURPOSE:To characterize the radiation dose and three-dimensional (3D) imaging performance of a recently developed mobile, isocentric C-arm equipped with a flat-panel detector (FPD) for intraoperative cone-beam computed tomography (CBCT) (Cios Spin 3D, Siemens Healthineers) and to identify potential improvements in 3D i...

journal_title：Medical physics

authors： Sheth NM,De Silva T,Uneri A,Ketcha M,Han R,Vijayan R,Osgood GM,Siewerdsen JH

更新日期：2020-03-01 00:00:00

abstract：PURPOSE:High-dose-rate brachytherapy (HDR-BT) is a treatment option for malignant skin diseases compared to external beam radiation therapy, HDR-BT provides improved target coverage, better organ sparing, and has comparable treatment times. This is especially true for large clinical targets with complex topologies. To ...

journal_title：Medical physics

authors： Guthier CV,Devlin PM,Harris TC,O'Farrell DA,Cormack RA,Buzurovic I

更新日期：2020-03-01 00:00:00

abstract：:Linac calibration is done in water, but patients are comprised primarily of soft tissue. Conceptually, and specified in NRG/RTOG trials, dose should be reported as dose-to-muscle to describe the dose to the patient. Historically, the dose-to-water of the linac calibration was often converted to dose-to-muscle for pati...

journal_title：Medical physics

authors： Kry SF,Feygelman V,Balter P,Knöös T,Charlie Ma CM,Snyder M,Tonner B,Vassiliev ON

更新日期：2020-03-01 00:00:00

abstract：PURPOSE:Radiotherapy is an effective treatment for many types of cancer in clinical settings. Gel dosimetry has the potential to record three-dimensional (3D) dose distribution compared to a conventional ion chamber. As the elasticity of the gel is altered after irradiation due to gel polymerization, we aim to measure ...

journal_title：Medical physics

authors： Xie WH,Su CT,Kao YJ,Chang TH,Chang YJ,Yao CH,Hsieh BY

更新日期：2020-03-01 00:00:00

abstract：PURPOSE:To quickly and automatically propagate organ contours from pretreatment to fraction images in magnetic resonance (MR)-guided prostate external-beam radiotherapy. METHODS:Five prostate cancer patients underwent 20 fractions of image-guided external-beam radiotherapy on a 1.5 T MR-Linac system. For each patient,...

journal_title：Medical physics

authors： Eppenhof KAJ,Maspero M,Savenije MHF,de Boer JCJ,van der Voort van Zyp JRN,Raaymakers BW,Raaijmakers AJE,Veta M,van den Berg CAT,Pluim JPW

更新日期：2020-03-01 00:00:00

abstract：PURPOSE:In this work, the fabrication, operation, and evaluation of a probe-format graphite calorimeter - herein referred to as Aerrow - as an absolute clinical dosimeter of high-energy photon beams while in the presence of a B = 1.5 T magnetic field is described. Comparable to a cylindrical ionization chamber (IC) in ...

journal_title：Medical physics

authors： Renaud J,Sarfehnia A,Bancheri J,Seuntjens J

更新日期：2020-03-01 00:00:00

abstract：PURPOSE:Radiosensitizer enhanced radiotherapy provides the possibility of improved treatment outcomes by preferentially increasing the effectiveness of radiation within the tumor. Proton therapy offers improved sparing of tissue distal of the tumor along the beam path and reduced integral dose compared to conventional ...

journal_title：Medical physics

authors： Peukert D,Kempson I,Douglass M,Bezak E

更新日期：2020-02-01 00:00:00

abstract：PURPOSE:To perform radiomic analysis of primary tumors extracted from pretreatment contrast-enhanced computed tomography (CE-CT) images for patients with oropharyngeal cancers to identify discriminant features and construct an optimal classifier for the characterization and prediction of human papilloma virus (HPV) sta...

journal_title：Medical physics

authors： Bagher-Ebadian H,Lu M,Siddiqui F,Ghanem AI,Wen N,Wu Q,Liu C,Movsas B,Chetty IJ

更新日期：2020-02-01 00:00:00