Computer-aided diagnosis in the era of deep learning.

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:To develop an automatic knot placement algorithm to enable the use of NonUniform Rational B-Splines (NURBS) in deformable image registration. METHODS:The authors developed a two-step approach to fit a known displacement vector field (DVF). An initial fit was made with uniform knot spacing. The error generated ...

journal_title：Medical physics

authors： Jacobson TJ,Murphy MJ

更新日期：2011-08-01 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：PURPOSE:There is evidence that computed tomography (CT) and positron emission tomography (PET) imaging metrics are prognostic and predictive in nonsmall cell lung cancer (NSCLC) treatment outcomes. However, few studies have explored the use of standardized uptake value (SUV)-based image features of nodal regions as pre...

journal_title：Medical physics

authors： Li H,Becker N,Raman S,Chan TC,Bissonnette JP

更新日期：2015-08-01 00:00:00

abstract：:Current dosimetry protocols for clinical protons do not take into account any secondary electron fluence perturbation in ion chambers. In this work, we performed a systematic study of secondary electron fluence perturbation factors for spherical and cylindrical ion chambers in proton beams (70-250 MeV). The electron f...

journal_title：Medical physics

authors： Verhaegen F,Palmans H

更新日期：2001-10-01 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：:Recent work has shown that there is significant uncertainty in measuring build-up doses in mega-voltage photon beams especially at high energies. In this present investigation we used a phantom-embedded extrapolation chamber (PEEC) made of Solid Water to validate Monte Carlo (MC)-calculated doses in the dose build-up ...

journal_title：Medical physics

authors： Abdel-Rahman W,Seuntjens JP,Verhaegen F,Deblois F,Podgorsak EB

更新日期：2005-01-01 00:00:00

abstract：PURPOSE:The advent of three-dimensional breast imaging systems such as digital breast tomosynthesis (DBT) has great promise for improving the detection and diagnosis of breast cancer. With these new technologies comes an essential need for testing methods to assess the resultant image quality. Although randomized clini...

journal_title：Medical physics

authors： Ikejimba LC,Salad J,Graff CG,Ghammraoui B,Cheng WC,Lo JY,Glick SJ

更新日期：2019-09-01 00:00:00

abstract：PURPOSE:Though failure mode and effects analysis (FMEA) is becoming more widely adopted for risk assessment in radiation therapy, to our knowledge, its output has never been validated against data on errors that actually occur. The objective of this study was to perform FMEA of a stereotactic body radiation therapy (SB...

journal_title：Medical physics

authors： Yang F,Cao N,Young L,Howard J,Logan W,Arbuckle T,Sponseller P,Korssjoen T,Meyer J,Ford E

更新日期：2015-06-01 00:00:00

abstract：:Intensity modulated radiation therapy (IMRT) with a dynamic multileaf collimator (DMLC) requires synchronization of DMLC leaf motion with dose delivery. A delay in DMLC communication is known to cause leaf lag and lead to dosimetric errors. The errors may be exacerbated by gated operation. The purpose of this study wa...

journal_title：Medical physics

authors： Duan J,Shen S,Fiveash JB,Brezovich IA,Popple RA,Pareek PN

更新日期：2003-08-01 00:00:00

abstract：:The objective of this work is to assess the suitability and performance of a new dosimeter system with a novel geometry for the quality assurance (QA) of volumetric modulated arc therapy (VMAT). The new dosimeter system consists of a hollow cylinder (15 and 25 cm inner and outer diameters) with 124 diodes embedded in ...

journal_title：Medical physics

authors： Létourneau D,Publicover J,Kozelka J,Moseley DJ,Jaffray DA

更新日期：2009-05-01 00:00:00

abstract：PURPOSE:To model X-ray coherent scatter diffraction patterns in GEANT4 for simulating experiments involving material detection through diffraction pattern measurement. Although coherent scatter cross-sections are modeled accurately in GEANT4, diffraction patterns for crystalline materials are not yet included. Here we ...

journal_title：Medical physics

authors： Kapadia A,Samei E,Harrawood B,Sahbaee P,Chawla A,Tan Z,Brady D

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:Dedicated breast PET/CT is expected to have utility in local staging, surgical planning, monitoring of therapy response, and detection of residual disease for breast cancer. Quantitative metrics will be integral to several such applications. The authors present a validation of fully 3D data correction schemes f...

journal_title：Medical physics

authors： Bowen SL,Ferrero A,Badawi RD

更新日期：2012-05-01 00:00:00

abstract：PURPOSE:Tissue textures have been recognized as biomarkers for various clinical tasks. In computed tomography (CT) image reconstruction, it is important but challenging to preserve the texture when lowering x-ray exposure from full- toward low-/ultra-low dose level. Therefore, this paper aims to explore the texture-dos...

journal_title：Medical physics

authors： Gao Y,Liang Z,Xing Y,Zhang H,Pomeroy M,Lu S,Ma J,Lu H,Moore W

更新日期：2020-10-01 00:00:00

abstract：:The trend toward conformal techniques in stereotactic radiosurgery necessitates an accurate and practical method for verification of irregular three-dimensional dose distributions. This work presents the design and evaluation of a phantom system facilitating the measurement of conformal dose distributions using one or...

journal_title：Medical physics

authors： Robar JL,Clark BG

更新日期：2000-05-01 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：PURPOSE:To evaluate both the Calypso Systems' (Calypso Medical Technologies, Inc., Seattle, WA) localization accuracy in the presence of wireless metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters of dose verification system (DVS, Sicel Technologies, Inc., Morrisville, NC) and the dosimeters' reading...

journal_title：Medical physics

authors： Su Z,Zhang L,Ramakrishnan V,Hagan M,Anscher M

更新日期：2011-05-01 00:00:00

abstract：:Approximately 70-85% of breast biopsies are performed on benign lesions. To reduce this high number of biopsies performed on benign lesions, a case-based reasoning (CBR) classifier was developed to predict biopsy results from BI-RADS findings. We used 1433 (931 benign) biopsy-proven mammographic cases. CBR similarity ...

journal_title：Medical physics

authors： Bilska-Wolak AO,Floyd CE Jr

更新日期：2002-09-01 00:00:00

abstract：:In addition to the familiar problems of reduced contrast and signal-to-noise ratio (SNR) in the single energy case, dual-energy subtractions in the presence of scattered radiation suffer further degradations from: (1) artifacts due to nonuniform subtraction of scatter, and (2) a serious deterioration of the signal of ...

journal_title：Medical physics

authors： Wagner FC,Macovski A,Nishimura DG

更新日期：1988-09-01 00:00:00

abstract：PURPOSE:To evaluate a three-equation three-unknown dual-energy quantitative CT (DEQCT) technique for determining region specific variations in bone spongiosa composition for improved red marrow dose estimation in radionuclide therapy. METHODS:The DEQCT method was applied to 80/140 kVp images of patient-simulating lumb...

journal_title：Medical physics

authors： Goodsitt MM,Shenoy A,Shen J,Howard D,Schipper MJ,Wilderman S,Christodoulou E,Chun SY,Dewaraja YK

更新日期：2014-05-01 00:00:00

abstract：:Photoelectric-enhanced radiation therapy is a bimodal therapy, consisting of the administration of highly radiation-absorbing substances into the tumor area and localized regional irradiation with orthovoltage x-rays. Irradiation can be performed by a modified computed tomography (CT) unit equipped with an additional ...

journal_title：Medical physics

authors： Jost G,Mensing T,Golfier S,Lawaczeck R,Pietsch H,Hütter J,Cibik L,Gerlach M,Krumrey M,Fratzscher D,Arkadiev V,Wedell R,Haschke M,Langhoff N,Wust P,Lüdemann L

更新日期：2009-06-01 00:00:00

abstract：:Multielectrode cochlear implantation is the most effective treatment for profound sensorineural hearing loss. In vivo three-dimensional 3-D localization of cochlear implant electrodes is important for modeling of the electrical field in the cochlea, design of electrode arrays, and may improve speech processor programm...

journal_title：Medical physics

authors： Yang S,Wang G,Skinner MW,Rubinstein JT,Vannier MW

更新日期：2000-04-01 00:00:00

abstract：:Most detectors in current positron emission tomography (PET) scanners and prototypes use lutetium oxyorthosilicate (LSO) or lutetium yttrium oxyorthosilicate (LYSO) scintillators. The aim of this work is to provide a complete set of background energy spectra, due to the scintillator intrinsic radioactivity, for a wide...

journal_title：Medical physics

authors： Domínguez-Jiménez DY,Alva-Sánchez H

更新日期：2021-01-21 00:00:00

abstract：:The attenuating properties of several types of lead (Pb)-based and non-Pb radiation shielding materials were studied and a correlation was made of radiation attenuation, materials properties, calculated spectra and ambient dose equivalent. Utilizing the well-characterized x-ray and gamma ray beams at the National Rese...

journal_title：Medical physics

authors： McCaffrey JP,Shen H,Downton B,Mainegra-Hing E

更新日期：2007-02-01 00:00:00

abstract：:Computed tomography dose index (CTDI) is a conventional indicator of the patient dose in CT studies. It is measured as the integration of the longitudinal single scan dose profile (SSDP) by using a 100-mm-long pencil ionization chamber and a single axial scan. However, the assumption that most of the SSDP is contained...

journal_title：Medical physics

authors： Nakonechny KD,Fallone BG,Rathee S

更新日期：2005-01-01 00:00:00

abstract：PURPOSE:CT reconstruction algorithms implemented on the GPU are highly sensitive to their implementation details and the hardware they run on. Fine-tuning an implementation for optimal performance can be a time consuming task and require many updates when the hardware changes. There are some techniques that do automati...

journal_title：Medical physics

authors： Papenhausen E,Zheng Z,Mueller K

更新日期：2013-03-01 00:00:00

abstract：:To develop volumetric micro-CT fluoroscopy for small animal imaging, we have proposed a cone-beam system with multiple x-ray sources. In this paper, we extend Parker's single-source half-scan weighting scheme to the case of an odd number of x-ray sources that are equiangularly distributed, and apply it for half-scan F...

journal_title：Medical physics

authors： Liu Y,Liu H,Wang Y,Wang G

更新日期：2001-07-01 00:00:00

abstract：PURPOSE:Radiosurgery uses small fields and high-radiation doses to treat intra- and extracranial lesions in a single session. The lack of a lateral electronic equilibrium and the presence of high-dose gradients in these fields are challenges for adequate measurements. The availability of radiation detectors with the hi...

journal_title：Medical physics

authors： Larraga-Gutierrez JM,Garcia-Hernandez D,Garcia-Garduno OA,Galvan de la Cruz OO,Ballesteros-Zebadua P,Esparza-Moreno KP

更新日期：2012-10-01 00:00:00

abstract：PURPOSE:The x-ray performance evaluation of digital x-ray detectors is based on the calculation of the modulation transfer function (MTF), the noise power spectrum (NPS), and the resultant detective quantum efficiency (DQE). The flat images used for the extraction of the NPS should not contain any fixed pattern noise (...

journal_title：Medical physics

authors： Konstantinidis AC,Olivo A,Speller RD

更新日期：2011-12-01 00:00:00

abstract：:The computed tomography (CT) radiation dose to pediatric patients has received considerable attention recently. Moreover, it is important to be able to determine CT radiation doses for various patient sizes ranging from infants to large adults. The current AAPM protocol only measures CT radiation dose using a 16 cm ac...

journal_title：Medical physics

authors： Nickoloff EL,Dutta AK,Lu ZF

更新日期：2003-03-01 00:00:00