Physics process level discrimination of detections for GATE: assessment of contamination in SPECT and spurious activity in PET.

abstract：:We are developing computerized feature extraction and classification methods to analyze malignant and benign microcalcifications on digitized mammograms. Morphological features that described the size, contrast, and shape of microcalcifications and their variations within a cluster were designed to characterize microc...

journal_title：Medical physics

authors： Chan HP,Sahiner B,Lam KL,Petrick N,Helvie MA,Goodsitt MM,Adler DD

更新日期：1998-10-01 00:00:00

abstract：PURPOSE:This study introduces a new hybrid ZTE/Dixon MR-based attenuation correction (MRAC) method including bone density estimation for PET/MRI and quantifies the effects of bone attenuation on metastatic lesion uptake in the pelvis. METHODS:Six patients with pelvic lesions were scanned using fluorodeoxyglucose (18F-...

journal_title：Medical physics

authors： Leynes AP,Yang J,Shanbhag DD,Kaushik SS,Seo Y,Hope TA,Wiesinger F,Larson PE

更新日期：2017-03-01 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:Ablative hyperthermia (>55 °C) has been used as a definitive treatment for accessible solid tumors not amenable to surgery, whereas mild hyperthermia (40-45 °C) has been shown effective as an adjuvant for both radiotherapy and chemotherapy. An optimal mild hyperthermia treatment is spatially accurate, with prec...

journal_title：Medical physics

authors： Partanen A,Tillander M,Yarmolenko PS,Wood BJ,Dreher MR,Kohler MO

更新日期：2013-01-01 00:00:00

abstract：PURPOSE:To report on significant dose enhancement effects caused by magnetic fields aligned parallel to 6 MV photon beam radiotherapy of small lung tumors. Findings are applicable to future inline MRI-guided radiotherapy systems. METHODS:A total of eight clinical lung tumor cases were recalculated using Monte Carlo me...

journal_title：Medical physics

authors： Oborn BM,Ge Y,Hardcastle N,Metcalfe PE,Keall PJ

更新日期：2016-01-01 00:00:00

abstract：PURPOSE:To investigate dosimetry for ocular brachytherapy for a range of eye plaque models containing(103)Pd, (125)I, or (131)Cs seeds with model-based dose calculations. METHODS:Five representative plaque models are developed based on a literature review and are compared to the standardized COMS plaque, including pla...

journal_title：Medical physics

authors： Lesperance M,Martinov M,Thomson RM

更新日期：2014-03-01 00:00:00

abstract：:An analytic representation proposed for the relative intensity distribution of the extra-focal source in a two-component x-ray source model serves as the basis for calculation. From this representation, a closed-form expression for head scatter factors defined on the central beam axis is derived by integrating over th...

journal_title：Medical physics

authors： Yu MK,Sloboda R

更新日期：1995-12-01 00:00:00

abstract：:In the last 30 years, thousands of basic or clinical studies have been devoted to atherosclerosis or to the problem of restenosis after angioplasty. In these studies, axial stresses in the vessel wall have received practically no attention, contrary to circumferential stress and purely biological aspects. Based on a r...

journal_title：Medical physics

authors： Doriot PA,Dorsaz PA

更新日期：2005-02-01 00:00:00

abstract：PURPOSE:Treatments like radiotherapy and focused ultrasound in the abdomen require accurate motion tracking, in order to optimize dosage delivery to the target and minimize damage to critical structures and healthy tissues around the target. 4D ultrasound is a promising modality for motion tracking during such treatmen...

journal_title：Medical physics

authors： Vijayan S,Klein S,Hofstad EF,Lindseth F,Ystgaard B,Langø T

更新日期：2014-08-01 00:00:00

abstract：PURPOSE:Four-dimensional volumetric modulated arc therapy (4D VMAT) and four-dimensional intensity-modulated radiotherapy (4D IMRT) are developing radiation therapy treatment strategies designed to maximize dose conformality, minimize normal tissue dose, and deliver the treatment as efficiently as possible. The patient...

journal_title：Medical physics

authors： Klawikowski S,Tai A,Ates O,Ahunbay E,Li XA

更新日期：2018-04-01 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：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:Proton radiotherapy for head-and-neck cancer (HNC) aims to improve organ-at-risk (OAR) sparing over photon radiotherapy. However, it may be less robust for setup and range uncertainties. The authors investigated OAR sparing and plan robustness for spot-scanning proton planning techniques and compared these with...

journal_title：Medical physics

authors： Barten DL,Tol JP,Dahele M,Slotman BJ,Verbakel WF

更新日期：2015-11-01 00:00:00

abstract：PURPOSE:To develop an automated treatment planning strategy for external beam intensity-modulated radiation therapy (IMRT), including a deep learning-based three-dimensional (3D) dose prediction and a dose distribution-based plan generation algorithm. METHODS AND MATERIALS:A residual neural network-based deep learning...

journal_title：Medical physics

authors： Fan J,Wang J,Chen Z,Hu C,Zhang Z,Hu W

更新日期：2019-01-01 00:00:00

abstract：:A fast, geometric beam angle optimization (BAO) algorithm for clinical intensity-modulated radiation therapy (IMRT) was implemented on ten localized prostate cancer patients on the Radiation Therapy Oncology Group (RTOG) 0126 protocol. The BAO algorithm computed the beam intersection volume (BIV) within the rectum and...

journal_title：Medical physics

authors： Potrebko PS,McCurdy BM,Butler JB,El-Gubtan AS,Nugent Z

更新日期：2007-10-01 00:00:00

abstract：:The purpose of this paper is to determine the correlation between dose-volume histogram (DVH) and dose wall-histogram (DWH) in the evaluation of rectal complications for prostate cancer patients treated with three-dimensional conformal radiotherapy (3D-CRT). A retrospective analysis of DVHs and DWHs of a subset of 25 ...

journal_title：Medical physics

authors： García-Vicente F,Zapatero A,Floriano A,Cruz-Conde A,Perez L,Marín A,Mínguez C,Torres JJ

更新日期：2005-08-01 00:00:00

abstract：PURPOSE:A series of examples are presented in which potential errors in the delivery of radiation therapy were prevented through use of incident learning. These examples underscore the value of reporting near miss incidents. METHODS:Using a departmental incident learning system, eight incidents were noted over a two-y...

journal_title：Medical physics

authors： Ford EC,Smith K,Harris K,Terezakis S

更新日期：2012-11-01 00:00:00

abstract：PURPOSE:This study aimed to introduce heat map, a graphical data presentation method widely used in gene expression experiments, to the presentation and interpretation of image fidelity assessment data of compressed computed tomography (CT) images. METHODS:The authors used actual assessment data that consisted of five...

journal_title：Medical physics

authors： Lee H,Kim B,Kim KJ,Seo J,Park S,Shin YG,Lee KH

更新日期：2011-08-01 00:00:00

abstract：:Magnetic resonance images can be compromised by constant frequency (CF) noise, such as radio frequency (RF) noise. We investigate the effects of CF noise in four imaging methods with non-uniform k-space sampling: single-shot echo-planar imaging (EPI) with sinusoidal readout gradients, phase-encoded echo-planar spectro...

journal_title：Medical physics

authors： Du W,Karczmar GS,Pan X

更新日期：2002-08-01 00:00:00

abstract：PURPOSE:To develop a method of (a) calculating the dose rate of voxels within a proton field delivered using pencil beam scanning (PBS), and (b) reporting a representative dose rate for the PBS treatment field that enables correspondence between multiple treatment modalities. This method takes into account the unique s...

journal_title：Medical physics

authors： Folkerts MM,Abel E,Busold S,Perez JR,Krishnamurthi V,Ling CC

更新日期：2020-12-01 00:00:00

abstract：PURPOSE:Breast density is a significant breast cancer risk factor. Although various methods are used to estimate breast density, there is no standard measurement for this important factor. The authors are developing a breast density standardization method for use in full field digital mammography (FFDM). The approach c...

journal_title：Medical physics

authors： Heine JJ,Cao K,Beam C

更新日期：2009-12-01 00:00:00

abstract：:Accurate dosimetry of small-field photon beams tends to be difficult to perform due to the presence of lateral electronic disequilibrium and steep dose gradients. In stereotactic radiosurgery (SRS), small fields of 6-30 mm in diameter are used. Generally thermoluminescence dosimetry chips, Farmer, Thimble ion chamber,...

journal_title：Medical physics

authors： Vahc YW,Chung WK,Park KR,Lee JY,Lee YH,Kwon O,Kim S

更新日期：2001-03-01 00:00:00

abstract：PURPOSE:Episcleral eye plaque brachytherapy has been utilized in the treatment of intra-ocular malignancies, delivering large prescription doses to the apex of the tumor. Advances in dose calculation and image guidance, via calibrated fundus images, enable localization of the tumor and determination of dose to the macu...

journal_title：Medical physics

authors： Guida K,Niermann K,Malcolm A,Sternberg P,Munn G,Coffey C

更新日期：2012-06-01 00:00:00

abstract：:Ultrasound-induced blood stasis has been observed for more than 30 years. Most of the literature has been focused on the health risks associated with this phenomenon and methods employed to prevent stasis from occurring during ultrasound imaging. To date, experimental observations have been either in vitro or invasive...

journal_title：Medical physics

authors： Winey BA,Misic V,Liao L,Parker K,Fenton BM,Yu Y

更新日期：2006-06-01 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 aim of this work is to investigate the predictive power of a common conventional intensity modulated radiation therapy (IMRT) quality assurance (QA) performance metric, the gamma passing rate (%GP), through the analysis of the sensitivity and of the correlation between %GP and different dose discrepancies b...

journal_title：Medical physics

authors： Stasi M,Bresciani S,Miranti A,Maggio A,Sapino V,Gabriele P

更新日期：2012-12-01 00:00:00

abstract：PURPOSE:To develop an accurate and efficient single-marker-based optical tracking system to enhance patient safety and quality of care in radiotherapy. METHODS:The optical tracking system consists of a Polaris camera as well as in-house software. The camera is mounted inside the treatment room and detects the location...

journal_title：Medical physics

authors： Yan G,Lu B,Mittauer K,Liu C,Li J

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:Radioembolization with yttrium-90 microspheres may be optimized with patient-specific pretherapy treatment planning. Dose verification and validation of treatment planning methods require quantitative imaging of the post-therapy distribution of yttrium-90 (Y-90). Methods for quantitative imaging of Y-90 using b...

journal_title：Medical physics

authors： Yue J,Mauxion T,Reyes DK,Lodge MA,Hobbs RF,Rong X,Dong Y,Herman JM,Wahl RL,Geschwind JH,Frey EC

更新日期：2016-10-01 00:00:00

abstract：:Our purpose in this work was to assess the reliability of the calibration coefficient for magnetic resonance water proton chemical shift temperature mapping. Over a six month period, the calibration coefficient was measured 15 times in several different phantoms. A highly linear relationship between water proton chemi...

journal_title：Medical physics

authors： Wu T,Kendell KR,Felmlee JP,Lewis BD,Ehman RL

更新日期：2000-01-01 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