keyword
MENU ▼
Read by QxMD icon Read
search

4D CT

keyword
https://www.readbyqxmd.com/read/28715346/new-prospective-4d-ct-for-mitigating-the-effects-of-irregular-respiratory-motion
#1
Tinsu Pan, Rachael M Martin, Dershan Luo
Artifact caused by irregular respiration is a major source of error in 4D-CT imaging. We propose a new prospective 4D-CT to mitigate this source of error without new hardware, software or off-line data-processing on the GE CT scanner. We utilize the cine CT scan in the design of the new prospective 4D-CT. The cine CT scan at each position can be stopped by the operator when an irregular respiration occurs, and resumed when the respiration becomes regular. This process can be repeated at one or multiple scan positions...
July 17, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28712277/moderate-hypofractionated-image-guided-thoracic-radiotherapy-for-locally-advanced-node-positive-non-small-cell-lung-cancer-patients-with-very-limited-lung-function-a-case-report
#2
Farkhad Manapov, Olarn Roengvoraphoj, Minglun Li, Chukwuka Eze
Patients with locally advanced lung cancer and very limited pulmonary function (forced expiratory volume in 1 second [FEV1] ≤ 1 L) have dismal prognosis and undergo palliative treatment or best supportive care. We describe two cases of locally advanced node-positive non-small cell lung cancer (NSCLC) patients with very limited lung function treated with induction chemotherapy and moderate hypofractionated image-guided radiotherapy (Hypo-IGRT). Hypo-IGRT was delivered to a total dose of 45 Gy to the primary tumor and involved lymph nodes...
June 2017: Radiation Oncology Journal
https://www.readbyqxmd.com/read/28710184/diagnostic-value-of-four-dimensional-ct-angiography-in-arterial-erectile-dysfunction-using-320-detector-row-dynamic-volume-ct
#3
Cheng-Cheng Xu, Xin-Zhong Ruan, Yi-Fan Tang, Jiao-Hai Pan, Guo-Yao Wang, Qiu-Li Huang
The study aims to evaluate the diagnostic value of four-dimensional CT angiography (4D-CTA) in the diagnosis of arterial erectile dysfunction (ED) using 320-detector row dynamic volume CT. Arterial ED patients attributed to arterial insufficiency were enrolled. To induce penile erection, an intracavernous injection of corpus cavernosum with a vasoactive drug was administered. Patients were assigned into the erection hardness score (EHS) 1/2 group or EHS 3/4 group. Color duplex Doppler ultrasound (CDDU) was used to analyze blood flow spectrum...
July 14, 2017: Bioscience Reports
https://www.readbyqxmd.com/read/28690355/evaluation-of-lung-tumor-motion-management-in-radiation-therapy-with-dynamic-mri
#4
Seyoun Park, Rana Farah, Steven M Shea, Erik Tryggestad, Russell Hales, Junghoon Lee
Surrogate-based tumor motion estimation and tracing methods are commonly used in radiotherapy despite the lack of continuous real time 3D tumor and surrogate data. In this study, we propose a method to simultaneously track the tumor and external surrogates with dynamic MRI, which allows us to evaluate their reproducible correlation. Four MRI-compatible fiducials are placed on the patient's chest and upper abdomen, and multi-slice 2D cine MRIs are acquired to capture the lung and whole tumor, followed by two-slice 2D cine MRIs to simultaneously track the tumor and fiducials, all in sagittal orientation...
February 11, 2017: Proceedings of SPIE
https://www.readbyqxmd.com/read/28661100/estimation-of-lung-tumor-position-from-multiple-anatomical-features-on-4d-ct-using-multiple-regression-analysis
#5
Tomohiro Ono, Mitsuhiro Nakamura, Yoshinori Hirose, Kenji Kitsuda, Yuka Ono, Takashi Ishigaki, Masahiro Hiraoka
To estimate the lung tumor position from multiple anatomical features on four-dimensional computed tomography (4D-CT) data sets using single regression analysis (SRA) and multiple regression analysis (MRA) approach and evaluate an impact of the approach on internal target volume (ITV) for stereotactic body radiotherapy (SBRT) of the lung. Eleven consecutive lung cancer patients (12 cases) underwent 4D-CT scanning. The three-dimensional (3D) lung tumor motion exceeded 5 mm. The 3D tumor position and anatomical features, including lung volume, diaphragm, abdominal wall, and chest wall positions, were measured on 4D-CT images...
June 29, 2017: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28650133/imaging-in-primary-hyperparathyroidism-focus-on-the-evidence-based-diagnostic-performance-of-different-methods
#6
Giorgio Treglia, Pierpaolo Trimboli, Martin Huellner, Luca Giovanella
BACKGROUND: Primary hyperparathyroidism (PHPT) is a common endocrine disorder usually due to hyperfunctioning parathyroid glands (HP). Surgical removal of HP is the main treatment in PHPT, particularly in symptomatic patients. The correct detection and localization of HP is challenging and crucial as it may guide surgical treatment in patients with PHPT. To date, different imaging methods have been used to detect and localize HP in patients with PHPT including radiology, nuclear medicine and hybrid techniques...
June 23, 2017: Minerva Endocrinologica
https://www.readbyqxmd.com/read/28644151/ecg-based-4d-dose-reconstruction-of-cardiac-arrhythmia-ablation-with-carbon-ion-beams-application-in-a-porcine-model
#7
Daniel Richter, H Immo Lehmann, Anna Eichhorn, Anna M Constantinescu, Robert Kaderka, Matthias Prall, Patrick Lugenbiel, Mitsuru Takami, Dierk Thomas, Christoph Bert, Marco Durante, Douglas L Packer, Christian Graeff
Noninvasive ablation of cardiac arrhythmia by scanned particle radiotherapy is highly promising, but especially challenging due to cardiac and respiratory motion. Irradiations for catheter-free ablation in intact pigs were carried out at the GSI Helmholtz Center in Darmstadt using scanned carbon ions. Here, we present real-time electrocardiogram (ECG) data to estimate time-resolved (4D) delivered dose. For 11 animals, surface ECGs and temporal structure of beam delivery were acquired during irradiation. R waves were automatically detected from surface ECGs...
June 23, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28629434/reduction-of-breathing-irregularity-related-motion-artifacts-in-low-pitch-spiral-4d-ct-by-optimized-projection-binning
#8
René Werner, Christian Hofmann, Eike Mücke, Tobias Gauer
BACKGROUND: Respiration-correlated CT (4D CT) is the basis of radiotherapy treatment planning of thoracic and abdominal tumors. Current clinical 4D CT images suffer, however, from artifacts due to unfulfilled assumptions concerning breathing pattern regularity. We propose and evaluate modifications to existing low-pitch spiral 4D CT reconstruction protocols to counteract respective artifacts. METHODS: The proposed advanced reconstruction (AR) approach consists of two steps that build on each other: (1) statistical analysis of the breathing signal recorded during CT data acquisition and extraction of a patient-specific reference breathing cycle for projection binning; (2) incorporation of an artifact measure into the reconstruction...
June 19, 2017: Radiation Oncology
https://www.readbyqxmd.com/read/28622338/multi-phase-simultaneous-segmentation-of-tumor-in-lung-4d-ct-data-with-context-information
#9
Zhengwen Shen, Huafeng Wang, Weiwen Xi, Xiaogang Deng, Jin Chen, Yu Zhang
Lung 4D computed tomography (4D-CT) plays an important role in high-precision radiotherapy because it characterizes respiratory motion, which is crucial for accurate target definition. However, the manual segmentation of a lung tumor is a heavy workload for doctors because of the large number of lung 4D-CT data slices. Meanwhile, tumor segmentation is still a notoriously challenging problem in computer-aided diagnosis. In this paper, we propose a new method based on an improved graph cut algorithm with context information constraint to find a convenient and robust approach of lung 4D-CT tumor segmentation...
2017: PloS One
https://www.readbyqxmd.com/read/28617686/imaging-adult-patients-with-coarctation-of-the-aorta
#10
Akanksha N Thakkar, Ponraj Chinnadurai, C Huie Lin
PURPOSE OF REVIEW: To provide an overview of current recommendations and techniques used to image coarctations of the aorta. RECENT FINDINGS: Imaging of coarctation of the aorta in adults is moving away from conventional techniques such as echocardiography and invasive angiography. Echocardiography may assist in making the diagnosis but is limited in its ability to quantify the severity of coarctations. Current guidelines recommend that every patient with a coarctation must undergo a computed tomography (CT) or MRI scan for accurate delineation of morphology...
June 15, 2017: Current Opinion in Cardiology
https://www.readbyqxmd.com/read/28595774/feasibility-of-using-single-photon-counting-x-ray-for-lung-tumor-position-estimation-based-on-4d-ct
#11
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/28587761/itv-mid-ventilation-gating-or-couch-tracking-a-comparison-of-respiratory-motion-management-techniques-based-on-4d-dose-calculations
#12
Stefanie Ehrbar, Alexander Jöhl, Adrianna Tartas, Luisa Sabrina Stark, Oliver Riesterer, Stephan Klöck, Matthias Guckenberger, Stephanie Tanadini-Lang
PURPOSE: Respiratory motion-management techniques (MMT) aim to ensure tumor dose coverage while sparing lung tissue. Dynamic treatment-couch tracking of the moving tumor is a promising new MMT and was compared to the internal-target-volume (ITV) concept, the mid-ventilation (MidV) principle and the gating approach in a planning study based on 4D dose calculations. METHODS: For twenty patients with lung lesions, planning target volumes (PTV) were adapted to the MMT and stereotactic body radiotherapy treatments were prepared with the 65%-isodose enclosing the PTV...
June 3, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28585715/does-liver-resection-transplantation-affect-respiratory-induced-liver-motion-in-patients-with-hepatocellular-carcinoma
#13
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/28585063/enabling-real-time-volume-rendering-of-functional-magnetic-resonance-imaging-on-an-ios-device
#14
Joseph Holub, Eliot Winer
Powerful non-invasive imaging technologies like computed tomography (CT), ultrasound, and magnetic resonance imaging (MRI) are used daily by medical professionals to diagnose and treat patients. While 2D slice viewers have long been the standard, many tools allowing 3D representations of digital medical data are now available. The newest imaging advancement, functional MRI (fMRI) technology, has changed medical imaging from viewing static to dynamic physiology (4D) over time, particularly to study brain activity...
June 5, 2017: Journal of Digital Imaging: the Official Journal of the Society for Computer Applications in Radiology
https://www.readbyqxmd.com/read/28580809/cardiovascular-imaging-environment-will-the-future-be-cloud-based
#15
Nadine Kawel-Boehm, David A Bluemke
In cardiovascular CT and MR imaging large datasets have to be stored, post-processed, analyzed and distributed. Beside basic assessment of volume and function in cardiac magnetic resonance imaging e.g., more sophisticated quantitative analysis is requested requiring specific software. Several institutions cannot afford various types of software and provide expertise to perform sophisticated analysis. Areas covered: Various cloud services exist related to data storage and analysis specifically for cardiovascular CT and MR imaging...
June 13, 2017: Expert Review of Medical Devices
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
#16
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
#17
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/28574192/feasibility-study-of-ultrasound-imaging-for-stereotactic-body-radiation-therapy-with-active-breathing-coordinator-in-pancreatic-cancer
#18
Lin Su, Iulian Iordachita, Yin Zhang, Junghoon Lee, Sook Kien Ng, Juan Jackson, Ted Hooker, John Wong, Joseph M Herman, H Tutkun Sen, Peter Kazanzides, Muyinatu A Lediju Bell, Chen Yang, Kai Ding
PURPOSE: Stereotactic body radiation therapy (SBRT) allows for high radiation doses to be delivered to the pancreatic tumors with limited toxicity. Nevertheless, the respiratory motion of the pancreas introduces major uncertainty during SBRT. Ultrasound imaging is a non-ionizing, non-invasive, and real-time technique for intrafraction monitoring. A configuration is not available to place the ultrasound probe during pancreas SBRT for monitoring. METHODS AND MATERIALS: An arm-bridge system was designed and built...
July 2017: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28557310/larynx-motion-considerations-in-partial-larynx-volumetric-modulated-arc-therapy-for-early-glottic-cancer
#19
Houda Bahig, Phuc Félix Nguyen-Tan, Édith Filion, David Roberge, Pensavan Thanomsack, Jacques de Guise, Danis Blais, Robert Doucet, Laurent Létourneau-Guillon, Louise Lambert
INTRODUCTION: To assess laryngeal motion in early glottic cancer in order to determine safe margins for partial larynx volumetric modulated arc therapy (PL-VMAT), and to quantify dosimetric advantages of PL-VMAT. METHODS: This prospective study included T1-2N0 glottic cancers treated with whole larynx VMAT (WL-VMAT). Pre- and mid-treatment 4D-computed tomography (4D-CT) and dynamic magnetic resonance imaging (MRI) allowed for assessment of larynx swallowing and respiratory motion...
May 30, 2017: Journal of Medical Imaging and Radiation Oncology
https://www.readbyqxmd.com/read/28553594/comparison-of-18f-fluorocholine-positron-emission-tomography-computed-tomography-and-four-dimensional-computed-tomography-in-the-preoperative-localization-of-parathyroid-adenomas-initial-results
#20
Sameer K Taywade, Nishikant A Damle, Abhishek Behera, K Devasenathipathy, Chandrasekhar Bal, Madhavi Tripathi, Shipra Agarwal, Nikhil Tandon, Sunil Chumber, V Seenu
OBJECTIVE: We aimed to compare the diagnostic accuracy of 18F-Fluorocholine (FCH)-positron emission tomography/computed tomography (PET/CT) and four-dimensional (4D)- CT in detection and localization of eutopic and ectopic parathyroid adenoma (PA) in patients with hyperparathyroidism. MATERIALS AND METHODS: Five patients with primary hyperparathyroidism underwent FCH-PET/CT after 60 min of 185 MBq of intravenous 18F-FCH administration. Images were acquired from head to mediastinum at 3 min per bed position...
May 2017: Indian Journal of Endocrinology and Metabolism
keyword
keyword
92855
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"