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https://www.readbyqxmd.com/read/28225778/gnb3-and-creb1-gene-polymorphisms-combined-with-negative-life-events-increase-susceptibility-to-major-depression-in-a-chinese-han-population
#1
Jingsong Ma, Lin Wang, Yanjie Yang, Zhengxue Qiao, Deyu Fang, Xiaohui Qiu, Xiuxian Yang, Xiongzhao Zhu, Jincai He, Hui Pan, Bo Ban, Yan Zhao, Hong Sui
BACKGROUND: Major depression (MD) is caused by a combination of genetic and environmental factors. In this study we investigated the interaction of variations in the G-protein beta 3 subunit (GNB3) and cAMP response element binding protein 1 (CREB1) genes with negative life events in the pathogenesis of MD. One GNB3 polymorphism (rs5443) and four CREB1 polymorphisms (rs2253206, rs2551941, rs6740584, rs11904814) were investigated based on known associations with MD. METHODS: 512 patients with MD and 513 control subjects were genotyped...
2017: PloS One
https://www.readbyqxmd.com/read/28216331/development-of-a-four-dimensional-monte-carlo-dose-calculation-system-for-real-time-tumor-tracking-irradiation-with-a-gimbaled-x-ray-head
#2
Yoshitomo Ishihara, Mitsuhiro Nakamura, Yuki Miyabe, Nobutaka Mukumoto, Yukinori Matsuo, Akira Sawada, Masaki Kokubo, Takashi Mizowaki, Masahiro Hiraoka
PURPOSE: To develop a four-dimensional (4D) dose calculation system for real-time tumor tracking (RTTT) irradiation by the Vero4DRT. METHODS: First, a 6-MV photon beam delivered by the Vero4DRT was simulated using EGSnrc. A moving phantom position was directly measured by a laser displacement gauge. The pan and tilt angles, monitor units, and the indexing time indicating the phantom position were also extracted from a log file. Next, phase space data at any angle were created from both the log file and particle data under the dynamic multileaf collimator...
February 16, 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28211367/high-quality-four-dimensional-cone-beam-ct-reconstruction-using-motion-compensated-total-variation-regularization
#3
Hua Zhang, Jianhua Ma, Zhaoying Bian, Dong Zeng, Qianjin Feng, Wufan Chen
Four dimensional cone-beam computed tomography (4D-CBCT) has great potential clinical value because its ability to describe tumor and organ motion. But the challenge in 4D-CBCT reconstruction is the limited number of projections at each phase, which resulting in the reconstruction full of noise and streak artifacts with the conventional analytical algorithms. To address this problem, in this paper, we propose a motion compensated total variation regularization approach which tries to maximum explore the temporal coherence of the spatial structures among 4D-CBCT phases...
February 17, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28211303/proposal-of-new-classification-of-femoral-trochanteric-fracture-by-three-dimensional-computed-tomography-and-relationship-to-usual-plain-x-ray-classification
#4
Etsuo Shoda, Shimpei Kitada, Yu Sasaki, Hitoshi Hirase, Takahiro Niikura, Sang Yang Lee, Atsushi Sakurai, Keisuke Oe, Takeharu Sasaki
PURPOSE: Classification of femoral trochanteric fractures is usually based on plain X-ray findings using the Evans, Jensen, or AO/OTA classification. However, complications such as nonunion and cut out of the lag screw or blade are seen even in stable fracture. This may be due to the difficulty of exact diagnosis of fracture pattern in plain X-ray. Computed tomography (CT) may provide more information about the fracture pattern, but such data are scarce. In the present study, it was performed to propose a classification system for femoral trochanteric fractures using three-dimensional CT (3D-CT) and investigate the relationship between this classification and conventional plain X-ray classification...
January 2017: Journal of Orthopaedic Surgery
https://www.readbyqxmd.com/read/28211058/a-feasibility-study-of-a-hybrid-breast-immobilization-system-for-early-breast-cancer-in-proton-beam-therapy
#5
Takeshi Arimura, Takashi Ogino, Takashi Yoshiura, Mitsugi Matsuyama, Naoaki Kondo, Hideki Miyazaki, Akari Sakuragi, Takayuki Ohara, Etsuyo Ogo, Yoshio Hishikawa
PURPOSE: We aimed to develop a new breast-immobilizing system for proton beam therapy (PBT) of early breast cancer (EBC) that would provide the optimum breast shape during the treatment as well as increased fixation reliability by reducing the influence of respiratory movement. METHODS: The breast-immobilizing system (HyBIS; Hybrid Breast-Immobilizing System) consists of a whole body immobilization system (WBIS), position converting device (to change patient position), photo scanning system, breast cup (made using a three-dimensional printer), breast cup fitting apparatus, breast cup holding device (to ensure the breast remains lifted in the supine position), and dedicated stretcher fixed to the WBIS (to carry the patient)...
February 16, 2017: Medical Physics
https://www.readbyqxmd.com/read/28197816/analysis-of-variation-in-bronchovascular-pattern-of-the-right-middle-and-lower-lobes-of-the-lung-using-three-dimensional-ct-angiography-and-bronchography
#6
Toshiteru Nagashima, Kimihiro Shimizu, Yoichi Ohtaki, Kai Obayashi, Seshiru Nakazawa, Akira Mogi, Hiroyuki Kuwano
OBJECTIVES: General thoracic surgeons must be familiar with anatomical variation in the pulmonary vessels and bronchi. Here, we analyzed the bronchovascular pattern of the right middle lobe (RML) and right lower lobe (RLL) of the lung using three-dimensional CT angiography and bronchography (3DCTAB). METHODS: We reviewed the anatomical patterns of the pulmonary vessels and bronchi in 270 patients using 3DCTAB images. RESULTS: The branching patterns of vessels and bronchi of RML and S(6) were classified according to the number of stems...
February 14, 2017: General Thoracic and Cardiovascular Surgery
https://www.readbyqxmd.com/read/28197760/automated-identification-and-reduction-of-artifacts-in-cine-four-dimensional-computed-tomography-4dct-images-using-respiratory-motion-model
#7
Min Li, Sarah Joy Castillo, Richard Castillo, Edward Castillo, Thomas Guerrero, Liang Xiao, Xiaolin Zheng
PURPOSE: Four-dimensional computed tomography (4DCT) images are often marred by artifacts that substantially degrade image quality and confound image interpretation. Human observation remains the standard method of 4DCT artifact evaluation, which is time-consuming and subjective. We develop a method to automatically identify and reduce artifacts in cine 4DCT images. METHODS: We proposed an algorithm that consisted of two main stages: deformable image registration and respiratory motion simulation...
February 14, 2017: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/28191461/three-class-mammogram-classification-based-on-descriptive-cnn-features
#8
M Mohsin Jadoon, Qianni Zhang, Ihsan Ul Haq, Sharjeel Butt, Adeel Jadoon
In this paper, a novel classification technique for large data set of mammograms using a deep learning method is proposed. The proposed model targets a three-class classification study (normal, malignant, and benign cases). In our model we have presented two methods, namely, convolutional neural network-discrete wavelet (CNN-DW) and convolutional neural network-curvelet transform (CNN-CT). An augmented data set is generated by using mammogram patches. To enhance the contrast of mammogram images, the data set is filtered by contrast limited adaptive histogram equalization (CLAHE)...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28190518/brain-computed-tomography-compared-with-facial-3-dimensional-computed-tomography-for-diagnosis-of-facial-fractures
#9
Sun Hwa Lee, Seong Jong Yun, Seokyong Ryu, Seoung Won Choi, Hye Jin Kim, Tae Kyug Kang, Sung Chan Oh, Suk Jin Cho
OBJECTIVES: To compare the detection of facial fractures and radiation dose between brain computed tomography (CT) and facial 3-dimensional (3D) CT in pediatric patients who have experienced a trauma. STUDY DESIGN: Four hundred pediatric patients who experienced a trauma and underwent immediate brain CT and facial 3D CT between January 2016 and June 2016 were included in this retrospective study. Two reviewers independently analyzed and determined the presence of the facial fractures of 8 anatomic regions based on brain CT and facial 3D CT over a 1-week interval...
February 9, 2017: Journal of Pediatrics
https://www.readbyqxmd.com/read/28181819/dose-escalation-study-with-respiratory-gated-carbon-ion-scanning-radiotherapy-using-a-simultaneous-integrated-boost-for-pancreatic-cancer-simulation-with-four-dimensional-computed-tomography
#10
Shohei Kawashiro, Shinichiro Mori, Shigeru Yamada, Kentaro Miki, Kenji Nemoto, Hiroshi Tsuji, Tadashi Kamada
OBJECTIVES: Pancreatic cancer is a difficult-to-treat disease with a persistently high mortality rate. We evaluated dose distribution simulation with respiratory-gated carbon-ion pencil beam scanning (C-PBS) with a simultaneous integrated boost (SIB) to increase tumor dose, sparing organs at risk (OARs). METHODS: Using four-dimensional computed tomography (4DCT) data of 12 patients, we delineated gross tumor volume (GTV) and two clinical target volumes (CTVs). To consider beam range intrafractional uncertainty, we calculated field-specific target volumes (FTVs), from which two planning target volumes (PTVs) were generated...
February 9, 2017: British Journal of Radiology
https://www.readbyqxmd.com/read/28168935/reproducibility-of-a-noninvasive-system-for-eye-positioning-and-monitoring-in-stereotactic-radiotherapy-of-ocular-melanoma
#11
Omar Iskanderani, Dominique Béliveau-Nadeau, Robert Doucet, Geneviève Coulombe, Deborah Pascale, David Roberge
PURPOSE: Our preferred treatment for juxtapapillary choroidal melanoma is stereotactic radiotherapy. We aim to describe our immobilization system and quantify its reproducibility. MATERIALS AND METHODS: Patients were identified in our radiosurgery database. Patients were imaged at computed tomography simulator with an in-house system which allows visual monitoring of the eye as the patient fixates a small target. All patients were reimaged at least once prior to and/or during radiotherapy...
January 1, 2017: Technology in Cancer Research & Treatment
https://www.readbyqxmd.com/read/28168813/the-impacts-of-mid-treatment-cbct-guided-patient-repositioning-on-target-coverage-during-lung-vmat
#12
Dominique Mathieu, Marie-Pierre Campeau, Stéphane Bedwani, David Roberge, Robert Doucet, Karim Zerouali, Houda Bahig, Toni Vu, Louise Lambert, Laura Masucci, Edith Filion
INTRODUCTION: The purpose of this study is quantify intrafraction motion (IFM) during lung volumetric-modulated arc therapy (VMAT) and evaluate the impact of mid-treatment cone beam computed tomography (CBCT)-guided patient repositioning on target coverage. METHOD: This analysis included lung tumours treated with VMAT to 50-60 Gy in 3-5 fractions. Treatment planning was based on four-dimensional CT scans from which internal tumour volumes (ITV) were derived. An isotropic 5 mm margin was added to obtain the final planning target volume (PTV)...
February 7, 2017: Journal of Medical Imaging and Radiation Oncology
https://www.readbyqxmd.com/read/28168163/results-of-a-single-institution-experience-with-dose-escalated-chemoradiation-for-locally-advanced-unresectable-non-small-cell-lung-cancer
#13
Mark E Bernard, Scott M Glaser, Beant S Gill, Sushil Beriwal, Dwight E Heron, James D Luketich, David M Friedland, Mark A Socinski, Joel S Greenberger
BACKGROUND: We determined factors associated with morbidity and outcomes of a series of non-small cell lung cancer (NSCLC) patients treated with dose-escalated chemoradiotherapy at the University of Pittsburgh Lung Cancer Program. METHODS AND MATERIALS: The records of 170 stage III NSCLC patients treated with definitive intent were retrospectively reviewed. All patients received four-dimensional CT simulation scan and had respiratory gating if tumor movement exceeded 5 mm...
2017: Frontiers in Oncology
https://www.readbyqxmd.com/read/28161602/characterizing-mandibular-growth-using-three-dimensional-imaging-techniques-and-anatomic-landmarks
#14
Michael P Kelly, Houri K Vorperian, Yuan Wang, Katelyn K Tillman, Helen M Werner, Moo K Chung, Lindell R Gentry
OBJECTIVE: To provide quantitative data on the multi-planar growth of the mandible, this study derived accurate linear and angular mandible measurements using landmarks on three dimensional (3D) mandible models. This novel method was used to quantify 3D mandibular growth and characterize the emergence of sexual dimorphism. DESIGN: Cross-sectional and longitudinal imaging data were obtained from a retrospective computed tomography (CT) database for 51 typically developing individuals between the ages of one and nineteen years...
January 23, 2017: Archives of Oral Biology
https://www.readbyqxmd.com/read/28160228/respiratory-gating-and-multifield-technique-radiotherapy-for-esophageal-cancer
#15
Atsushi Ohta, Motoki Kaidu, Satoshi Tanabe, Satoru Utsunomiya, Ryuta Sasamoto, Katsuya Maruyama, Kensuke Tanaka, Hirotake Saito, Toshimichi Nakano, Miki Shioi, Haruna Takahashi, Naotaka Kushima, Eisuke Abe, Hidefumi Aoyama
PURPOSE: To investigate the effects of a respiratory gating and multifield technique on the dose-volume histogram (DVH) in radiotherapy for esophageal cancer. METHODS AND MATERIALS: Twenty patients who underwent four-dimensional computed tomography for esophageal cancer were included. We retrospectively created the four treatment plans for each patient, with or without the respiratory gating and multifield technique: No gating-2-field, No gating-4-field, Gating-2-field, and Gating-4-field plans...
February 3, 2017: Japanese Journal of Radiology
https://www.readbyqxmd.com/read/28155703/numerical-study-of-the-effects-of-bronchial-structural-abnormalities-on-respiratory-flow-distribution
#16
Shen Yu, Jizhe Wang, Xiuzhen Sun, Yingxi Liu
BACKGROUND: The anatomical configurations of respiratory tract would be directly associated with their ventilatory function. It is necessary to fully understand the association between airway configurations and their functions as well as the interactions between different airway segments. In this study, we developed a respiratory airway model to investigate the effects of bronchial structural abnormalities on flow distribution in the bronchi and upper airway. METHODS: Derived from computed tomography (CT) scanner data, three-dimensional (3D) finite element (FE) models of healthy human respiratory tracts were developed with anatomically realistic configurations, including the nasal cavity, oral cavity, pharynx, larynx, trachea, and partial bronchi...
December 28, 2016: Biomedical Engineering Online
https://www.readbyqxmd.com/read/28152259/four-dimensional-phase-contrast-vastly-undersampled-isotropic-projection-reconstruction-4d-pc-vipr-mr-evaluation-of-the-renal-arteries-in-transplant-recipients-preliminary-results
#17
Daisuke Motoyama, Yasuo Ishii, Yasuo Takehara, Masataka Sugiyama, Wang Yang, Hatsuko Nasu, Takasuke Ushio, Yuko Hirose, Naoki Ohishi, Tetsuya Wakayama, Hiroyuki Kabasawa, Kevin Johnson, Oliver Wieben, Harumi Sakahara, Seiichiro Ozono
PURPOSE: To assess the performance of four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) at 3.0T in depicting intrarenal arteries compared with computed tomography angiography (CTA), and its correlation with arterial flowmetry in comparison with Doppler ultrasonography (DUS). MATERIALS AND METHODS: In our prospective single-arm study, subjects were 25 patients who underwent renal transplant-related surgery at our hospital between July 2011 and June 2015...
February 2, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28142009/three-dimensional-analysis-of-long-term-stability-after-bilateral-sagittal-split-ramus-osteotomy-fixed-with-a-single-miniplate-with-4-monocortical-screws-and-1-bicortical-screw-a-retrospective-2-center-study
#18
F Hernández-Alfaro, M Raffaini, A Paredes-de-Sousa-Gil, A S Magri, R Guijarro-Martínez, A Valls-Ontañón
PURPOSE: This study evaluated the long-term stability of bilateral sagittal split ramus osteotomy fixed with a single miniplate with 4 monocortical screws and 1 bicortical screw (hybrid technique [HT]) using 3-dimensional (3D) analysis and an objective measuring tool, cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Sixty-four patients who underwent bimaxillary surgery with mandibular advancement fixed with the HT were selected from 2 different institutions and enrolled in this retrospective study...
January 4, 2017: Journal of Oral and Maxillofacial Surgery
https://www.readbyqxmd.com/read/28140361/directional-sinogram-interpolation-for-motion-weighted-4d-cone-beam-ct-reconstruction
#19
Hua Zhang, Matthijs Kruis, Jan-Jakob Sonke
The image quality of respiratory sorted four-dimensional (4D) cone-beam (CB) computed tomography (CT) is often limited by streak artifacts due to insufficient projections. A motion weighted reconstruction (MWR) method is proposed to decrease streak artifacts and improve image quality. Firstly, respiratory correlated CBCT projections were interpolated by directional sinogram interpolation (DSI) to generate additional CB projections for each phase and subsequently reconstructed. Secondly, local motion was estimated by deformable image registration of the interpolated 4D CBCT...
January 31, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28133755/evaluation-of-motion-mitigation-using-abdominal-compression-in-the-clinical-implementation-of-pencil-beam-scanning-proton-therapy-of-liver-tumors
#20
Liyong Lin, Kevin Souris, Minglei Kang, Adam Glick, Haibo Lin, Sheng Huang, Kristin Stützer, Guillaume Janssens, Edmond Sterpin, John A Lee, Timothy D Solberg, James E McDonough, Charles B Simone, Edgar Ben-Josef
PURPOSE: To determine whether individual liver tumor patients can be safely treated with pencil beam scanning proton therapy. This study reports a planning preparation workflow that can be used for beam angle selection and the evaluation of the efficacy of abdominal compression (AC) to mitigate motion. METHODS: Four-dimensional computed tomography scans (4DCT) with and without AC were available from 10 liver tumor patients with fluoroscopy-proven motion reduction by AC, previously treated using photons...
December 9, 2016: Medical Physics
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