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Four dimensional ct

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https://www.readbyqxmd.com/read/28635614/advanced-treatment-planning-using-direct-4d-optimisation-for-pencil-beam-scanned-particle-therapy
#1
Kinga Bernatowicz, Ye Zhang, Rosalind Lucy Perrin, Damien Charles Weber, Antony John Lomax
We report on development of a new four-dimensional (4D) optimisation approach for scanned proton beams, which incorporates both irregular motion patterns and the delivery dynamics of the treatment machine into the plan optimiser. Furthermore, we assess the effectiveness of this technique to reduce dose to critical structures in proximity to moving targets, while maintaining effective target dose homogeneity and coverage. The proposed approach has been tested using both a simulated phantom and a clinical liver cancer case, and allows for realistic 4D calculations and optimisation using irregular breathing patterns extracted from e...
June 21, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28630168/incidence-and-factors-associated-with-the-occurrence-of-pulmonary-vein-narrowing-after-cryoballoon-ablation
#2
Ryohsuke Narui, Michifumi Tokuda, Masato Matsushima, Ryota Isogai, Kenichi Tokutake, Kenichi Yokoyama, Mika Hioki, Keiichi Ito, Shin-Ichi Tanigawa, Seigo Yamashita, Keiichi Inada, Kenri Shibayama, Seiichiro Matsuo, Satoru Miyanaga, Kenichi Sugimoto, Michihiro Yoshimura, Teiichi Yamane
BACKGROUND: In contrast with traditional radiofrequency ablation, little is known about the influence of cryoballoon ablation on the morphology of pulmonary veins (PVs). We evaluated the influence of cryoballoon ablation on the PV dimension (PVD) and investigated the factors associated with a reduction of the PVD. METHODS AND RESULTS: Seventy-four patients who underwent cryoballoon ablation for paroxysmal atrial fibrillation were included in the present study. All subjects underwent contrast-enhanced computed tomography both before and at 3 months after the procedure...
June 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28628156/-atlantoaxial-reduction-and-fixation-guided-by-the-intraoperative-ct
#3
(no author information available yet)
OBJECTIVE: To evaluate the clinical result of atlantoaxial reduction and fixation guided by the intraoperative CT. METHODS: Sixteen cases were retrospectively studied, including seven males and nine females, with the mean age of 49.9 years. Twelve cases were diagnosed as chronic atlantoaxial instability or dislocation, while four cases as acute odontoid fracture and dislocation. Among the sixteen cases, fourteen underwent atlantoaxial fusion, while two underwent temporary atlantoaxial fixation without fusion...
June 18, 2017: Beijing da Xue Xue Bao. Yi Xue Ban, Journal of Peking University. Health Sciences
https://www.readbyqxmd.com/read/28625908/-on-the-spot-the-use-of-4d-cta-to-differentiate-a-true-spot-sign-from-a-distal-intracranial-aneurysm
#4
Johanna P de Jong, Leo Kluijtmans, Martinus J van Amerongen, Mathias Prokop, Hieronymus D Boogaarts, Frederick J A Meijer
BACKGROUND: Spontaneous intracerebral hemorrhage may arise from underlying abnormalities including aneurysms. Computed tomography angiography (CTA) is widely used for the detection of possible underlying causes, which is important since it may have immediate therapeutic consequences. In addition, CTA is used to detect the so-called "spot sign", indicating active hemorrhage which carries a worse prognosis. CTA is, however, a snapshot in time. Four-dimensional CTA (4D-CTA) is a dynamic type of imaging and has emerged as a valuable imaging technique for different neurovascular disorders...
June 15, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28619493/dynamic-4d-cta-for-neuro-vascular-pathologies-a-case-series
#5
Ahmed Alnemari, Tarek R Mansour, Mohamad Bazerbashi, Mark Buehler, Jason Schroeder, Daniel Gaudin
BACKGROUND: The aim of this article is to illustrate, summarize, and review the multifaceted application of four-dimensional computed tomography angiography (4D-CTA) in the characterization and diagnosis of various cerebrovascular and tumor-associated vascular pathologies through the presentation of clinical cases including acute/chronic stroke, arteriovenous malformations, aneurysm, moya-moya disease, and the hypervascularity associated with a tumor and its relationship to pre-operative embolization...
June 12, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28618799/biosonar-signal-propagation-in-the-harbor-porpoise-s-phocoena-phocoena-head-the-role-of-various-structures-in-the-formation-of-the-vertical-beam
#6
Chong Wei, Whitlow W L Au, Darlene R Ketten, Zhongchang Song, Yu Zhang
Harbor porpoises (Phocoena phocoena) use narrow band echolocation signals for detecting and locating prey and for spatial orientation. In this study, acoustic impedance values of tissues in the porpoise's head were calculated from computer tomography (CT) scan and the corresponding Hounsfield Units. A two-dimensional finite element model of the acoustic impedance was constructed based on CT scan data to simulate the acoustic propagation through the animal's head. The far field transmission beam pattern in the vertical plane and the waveforms of the receiving points around the forehead were compared with prior measurement results, the simulation results were qualitatively consistent with the measurement results...
June 2017: Journal of the Acoustical Society of America
https://www.readbyqxmd.com/read/28610697/respiratory-motion-of-adrenal-gland-metastases-analyses-using-four-dimensional-computed-tomography-images
#7
Bing Chen, Yong Hu, Jin Liu, An-Ning Cao, Lu-Xi Ye, Zhao-Chong Zeng
PURPOSE: To evaluate the respiratory motion of adrenal gland metastases in three-dimensional directions using four-dimensional computed tomography (4DCT) images. METHODS: From January 2013 to May 2016, 12 patients with adrenal gland metastases were included in this study. They all underwent 4DCT scans to assess respiratory motion of adrenal gland metastases in free breathing state. The 4DCT images were sorted into 10 image series according to the respiratory phase from the end inspiration to the end expiration, and then transferred to FocalSim workstation...
June 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28608450/analysis-of-giant-thoracic-neoplasms-correlations-between-imaging-pathology-and-surgical-management
#8
Zhen Feng, Meng Li, Fang Liu, Yue Peng, Wangang Ren, Hounai Xie, Zhongmin Peng
BACKGROUND: A giant thoracic neoplasm is extremely rare and poorly understood. Our systemic study introduced computed tomography angiography (CTA) with three-dimensional (3D) reconstruction imaging and evaluated correlations between imaging, pathology, and surgical management. METHODS: Data from 45 patients undergoing surgery for giant thoracic neoplasm in our institution between May 2007 and November 2015 were collected. The clinical characteristics, imaging manifestations, preoperative biopsy, surgical management, postoperative pathology, and prognosis and their correlation were analyzed...
June 13, 2017: Thoracic Cancer
https://www.readbyqxmd.com/read/28606593/sub-solid-nodule-detection-performance-on-reduced-dose-computed-tomography-with-iterative-reduction-comparison-between-20%C3%A2-ma-7%C3%A2-mas-and-120%C3%A2-ma-42%C3%A2-mas-regarding-nodular-size-and-characteristics-and-association-with-size-specific-dose-estimate
#9
Yukihiro Nagatani, Masashi Takahashi, Mitsuru Ikeda, Tsuneo Yamashiro, Hisanobu Koyama, Mitsuhiro Koyama, Hiroshi Moriya, Satoshi Noma, Noriyuki Tomiyama, Yoshiharu Ohno, Kiyoshi Murata, Sadayuki Murayama
RATIONALE AND OBJECTIVES: This study aimed to compare sub-solid nodule detection performances (SSNDP) on chest computed tomography (CT) with Adaptive Iterative Dose Reduction using Three Dimensional Processing (AIDR 3D) between 7 mAs (0.21 mSv) and 42 mAs (1.28 mSv) in total and in subgroups classified by nodular size, characteristics, and location, and analyze the association of SSNDP with size-specific dose estimate (SSDE). MATERIALS AND METHODS: As part of the Area-detector Computed Tomography for the Investigation of Thoracic Diseases Study, a Japanese multicenter research project, 68 subjects underwent chest CT with 120 kV, 0...
June 9, 2017: Academic Radiology
https://www.readbyqxmd.com/read/28606197/dynamic-four-dimensional-ct-angiography-for-the-assessment-of-pulmonary-perfusion-in-an-adult-patient-with-pulmonary-artery-occlusion-and-major-aortopulmonary-collateral-after-multistage-repair-of-fallot-s-pentalogy
#10
Dirk Loßnitzer, Stefan Baumann, Thomas Henzler
Dynamic CT angiography provides haemodynamic assessment combined with detailed information on complex cardiac anatomy in patients with congenital malformations such as multistage correction of Fallot's Pentalogy.
June 13, 2017: Cardiology in the Young
https://www.readbyqxmd.com/read/28596273/novel-analysis-of-4dct-imaging-quantifies-progressive-increases-in-anatomic-dead-space-during-mechanical-ventilation-in-mice
#11
Elizabeth H Kim, Melissa Preissner, Richard Carnibella, Chaminda R Samarage, Ellen Bennett, Andreas Fouras, Graeme R Zosky, Heather Dale Jones
PURPOSE: Increased dead space is an important prognostic marker in early acute respiratory distress syndrome (ARDS) that correlates with mortality. The cause of increased dead space in ARDS has largely been attributed to increased alveolar dead space due to ventilation/perfusion mismatching and shunt. We sought to determine if anatomic dead space also increases in response to mechanical ventilation. METHODS: Mice received intratracheal lipopolysaccharide (LPS) or saline and mechanical ventilation (MV)...
June 8, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/28595774/feasibility-of-using-single-photon-counting-x-ray-for-lung-tumor-position-estimation-based-on-4d-ct
#12
Katharina P Aschenbrenner, Christian V Guthier, Yulia Lyatskaya, Judit Boda-Heggemann, Frederik Wenz, Jürgen W Hesser
PURPOSE: In stereotactic body radiation therapy of lung tumors, reliable position estimation of the tumor is necessary in order to minimize normal tissue complication rate. While kV X-ray imaging is frequently used, continuous application during radiotherapy sessions is often not possible due to concerns about the additional dose. Thus, ultra low-dose (ULD) kV X-ray imaging based on a single photon counting detector is suggested. This paper addresses the lower limit of photons to locate the tumor reliably with an accuracy in the range of state-of-the-art methods, i...
June 5, 2017: Zeitschrift Für Medizinische Physik
https://www.readbyqxmd.com/read/28588150/dose-mapping-after-endoradiotherapy-with-177-lu-dotatate-toc-by-one-single-measurement-after-four-days
#13
Heribert Hänscheid, Constantin Lapa, Andreas K Buck, Michael Lassmann, Rudolf A Werner
Dosimetry of organs and tumors helps to assess risks and benefit of treatment with (177)Lu-DOTATATE/ TOC. However, it is often not performed in clinical routine because of additional efforts, the complexity of data collection and analysis, and the additional burden for the patients. Aiming at a simplification of dosimetry, we analyzed the accuracy of a theoretically substantiated approximation, which allows to calculate absorbed doses from a single measurement of the abdominal activity distribution. Methods: Activity kinetics were retrospectively assessed from planar images in 29 patients with neuroendocrine tumors (NET, n = 21) or meningioma (n = 8) after the administration of (177)Lu-DOTATATE (n = 22) or (177)Lu-DOTATOC (n = 7)...
June 6, 2017: Journal of Nuclear Medicine: Official Publication, Society of Nuclear Medicine
https://www.readbyqxmd.com/read/28585715/does-liver-resection-transplantation-affect-respiratory-induced-liver-motion-in-patients-with-hepatocellular-carcinoma
#14
Yong Hu, Yong-Kang Zhou, Yi-Xing Chen, Lu-Xi Ye, Zhao-Chong Zeng
The purpose of this study was to evaluate the changes in magnitude of three-dimensional (3D) liver motion after liver resection/transplantation in patients with hepatocellular carcinoma (HCC) using four-dimensional (4D)-computed tomography (CT) images. From January 2012 to April 2016, 74 HCC patients underwent 4D-CT scans under a free-breathing state to assess respiratory liver motion. Of the 74 patients, 40 did not have a liver resection/transplantation (Group A), 34 with liver resection/transplantation. 15 underwent major or minor resection in the right liver lobe (Group B), 14 underwent major or minor resection in the left liver lobe (Group C), and five underwent liver transplantation (Group D)...
June 6, 2017: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28585219/pet-ct-scanning-with-3d-acquisition-is-feasible-for-quantifying-myocardial-blood-flow-when-diagnosing-coronary-artery-disease
#15
Osamu Manabe, Masanao Naya, Tadao Aikawa, Masahiko Obara, Keiichi Magota, Markus Kroenke, Noriko Oyama-Manabe, Kenji Hirata, Daiki Shinyama, Chietsugu Katoh, Nagara Tamaki
BACKGROUND: The quantification of myocardial blood flow (MBF) and coronary flow reserve (CFR) are useful approaches for evaluating the functional severity of coronary artery disease (CAD). (15)O-water positron emission tomography (PET) is considered the gold standard method for MBF quantification. However, MBF measurements in (15)O-water PET with three-dimensional (3D) data acquisition, attenuation correction using computed tomography (CT), and time of flight have not been investigated in detail or validated...
December 2017: EJNMMI Research
https://www.readbyqxmd.com/read/28583623/pre-treatment-mdct-based-texture-analysis-for-therapy-response-prediction-in-gastric-cancer-comparison-with-tumour-regression-grade-at-final-histology
#16
Francesco Giganti, Paolo Marra, Alessandro Ambrosi, Annalaura Salerno, Sofia Antunes, Damiano Chiari, Elena Orsenigo, Antonio Esposito, Elena Mazza, Luca Albarello, Roberto Nicoletti, Carlo Staudacher, Alessandro Del Maschio, Francesco De Cobelli
PURPOSE: An accurate prediction of tumour response to therapy is fundamental in oncology, so as to prompt personalised treatment options if needed. The aim of this study was to investigate the ability of preoperative texture analysis from multi-detector computed tomography (MDCT) in the prediction of the response rate to neo-adjuvant therapy in patients with gastric cancer. MATERIAL AND METHODS: Thirty-four patients with biopsy-proven gastric cancer were examined by MDCT before neo-adjuvant therapy, and treated with radical surgery after treatment completion...
May 2017: European Journal of Radiology
https://www.readbyqxmd.com/read/28579281/interfractional-variability-of-respiration-induced-esophageal-tumor-motion-quantified-using-fiducial-markers-and-four-dimensional-cone-beam-computed-tomography
#17
Peng Jin, Maarten C C M Hulshof, Niek van Wieringen, Arjan Bel, Tanja Alderliesten
PURPOSE: To investigate the interfractional variability of respiration-induced esophageal tumor motion using fiducial markers and four-dimensional cone-beam computed tomography (4D-CBCT) and assess if a 4D-CT is sufficient for predicting the motion during the treatment. MATERIALS AND METHODS: Twenty-four patients with 63 markers visible in the retrospectively reconstructed 4D-CBCTs were included. For each marker, we calculated the amplitude and trajectory of the respiration-induced motion...
June 1, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28577254/the-value-of-whole-brain-ct-perfusion-imaging-and-ct-angiography-using-a-320-slice-ct-scanner-in-the-diagnosis-of-mci-and-ad-patients
#18
Bo Zhang, Guo-Jun Gu, Hong Jiang, Yi Guo, Xing Shen, Bo Li, Wei Zhang
OBJECTIVES: To validate the value of whole-brain computed tomography perfusion (CTP) and CT angiography (CTA) in the diagnosis of mild cognitive impairment (MCI) and Alzheimer's disease (AD). METHODS: Whole-brain CTP and four-dimensional CT angiography (4D-CTA) images were acquired in 30 MCI, 35 mild AD patients, 35 moderate AD patients, 30 severe AD patients and 50 normal controls (NC). Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and correlation between CTP and 4D-CTA were analysed...
June 2, 2017: European Radiology
https://www.readbyqxmd.com/read/28574987/reconstruction-of-stented-coronary-arteries-from-optical-coherence-tomography-images-feasibility-validation-and-repeatability-of-a-segmentation-method
#19
Claudio Chiastra, Eros Montin, Marco Bologna, Susanna Migliori, Cristina Aurigemma, Francesco Burzotta, Simona Celi, Gabriele Dubini, Francesco Migliavacca, Luca Mainardi
Optical coherence tomography (OCT) is an established catheter-based imaging modality for the assessment of coronary artery disease and the guidance of stent placement during percutaneous coronary intervention. Manual analysis of large OCT datasets for vessel contours or stent struts detection is time-consuming and unsuitable for real-time applications. In this study, a fully automatic method was developed for detection of both vessel contours and stent struts. The method was applied to in vitro OCT scans of eight stented silicone bifurcation phantoms for validation purposes...
2017: PloS One
https://www.readbyqxmd.com/read/28570019/clinical-assessment-of-cryoballoon-ablation-in-cases-with-atrial-fibrillation-and-a-left-common-pulmonary-vein
#20
Takatoshi Shigeta, Kaoru Okishige, Yasuteru Yamauchi, Hideshi Aoyagi, Tomofumi Nakamura, Mitsumi Yamashita, Takuro Nishimura, Naruhiko Ito, Yusuke Tsuchiya, Mitsutoshi Asano, Tsukasa Shimura, Hidetoshi Suzuki, Manabu Kurabayashi, Takehiko Keida, Tetsuo Sasano, Kenzo Hirao
INTRODUCTION: Pulmonary vein isolation (PVI) using a cryoballoon (CB) is a useful tool for treating atrial fibrillation (AF); however, the clinical efficacy of the CB has never been fully investigated in patients with a left common pulmonary vein (LCPV). METHODS AND RESULTS: Three hundred twenty-four consecutive paroxysmal AF patients underwent PVI with a CB. Three-dimensional computed tomography was performed in all patients before the ablation. The clinical outcomes of the AF ablation between patients with (Group A) and without an LCPV (Group B) were compared...
June 1, 2017: Journal of Cardiovascular Electrophysiology
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