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https://www.readbyqxmd.com/read/28797700/4dct-imaging-to-assess-radiomics-feature-stability-an-investigation-for-thoracic-cancers
#1
Ruben T H M Larue, Lien Van De Voorde, Janna E van Timmeren, Ralph T H Leijenaar, Maaike Berbée, Meindert N Sosef, Wendy M J Schreurs, Wouter van Elmpt, Philippe Lambin
BACKGROUND AND PURPOSE: Quantitative tissue characteristics derived from medical images, also called radiomics, contain valuable prognostic information in several tumour-sites. The large number of features available increases the risk of overfitting. Typically test-retest CT-scans are used to reduce dimensionality and select robust features. However, these scans are not always available. We propose to use different phases of respiratory-correlated 4D CT-scans (4DCT) as alternative. MATERIALS AND METHODS: In test-retest CT-scans of 26 non-small cell lung cancer (NSCLC) patients and 4DCT-scans (8 breathing phases) of 20 NSCLC and 20 oesophageal cancer patients, 1045 radiomics features of the primary tumours were calculated...
August 7, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28793141/factors-associated-with-discordance-between-preoperative-parathyroid-4-dimensional-computed-tomographic-scans-and-intraoperative-findings-during-parathyroidectomy
#2
Shonan Sho, Alexander D Yuen, Michael W Yeh, Masha J Livhits, Ali R Sepahdari
Importance: Parathyroid 4-dimensional computed tomographic scans (4D-CTs) have emerged as an accurate and cost-effective initial localization study for patients with primary hyperparathyroidism. However, potential limitations and factors affecting the accuracy of preoperative 4D-CTs remain poorly defined. Objectives: To characterize factors associated with missed parathyroid lesions on preoperative 4D-CTs and to investigate patterns of commonly observed errors. Design, Setting, and Participants: A prospectively accrued patient database was analyzed from September 1, 2011, through October 31, 2016...
August 9, 2017: JAMA Surgery
https://www.readbyqxmd.com/read/28780900/results-from-a-clinical-trial-evaluating-the-efficacy-of-real-time-body-surface-visual-feedback-in-reducing-patient-motion-during-lung-cancer-radiotherapy
#3
Gareth J Price, Corinne Faivre-Finn, Julia Stratford, Sheena Chauhan, Michelle Bewley, Laura Clarke, Corinne N Johnson, Christopher J Moore
INTRODUCTION: Optical surface measurement devices are a maturing technology in radiotherapy. The challenge for such devices is to demonstrate how they can improve clinical care. We present results from a phase 1 clinical trial designed to test the hypothesis that if presented with live data from a novel optical measurement device, showing their deviation from an ideal radiotherapy treatment position, patients will be able to better control their motion and increase their geometrical conformance...
August 7, 2017: Acta Oncologica
https://www.readbyqxmd.com/read/28766726/a-novel-3d-printed-phantom-insert-for-4d-pet-ct-imaging-and-simultaneous-integrated-boost-radiotherapy
#4
Laura Cerviño, Dima Soultan, Mariel Cornell, Adam Yock, Niclas Pettersson, William Y Song, Joseph Aguilera, Sunil Advani, James Murphy, Carl Ho, Claude James, Anthony Paravati, Robin Coope, Bradford Gill, Vitali Moiseenko
PURPOSE: To construct a 3D-printed phantom insert designed to mimic the variable PET tracer uptake seen in lung tumor volumes and a matching dosimetric insert to be used in simultaneous integrated boost (SIB) phantom studies, and to evaluate the design through end-to-end tests. METHODS: A set of phantom inserts was designed and manufactured for a realistic representation of gated radiotherapy steps from 4D PET/CT scanning to dose delivery. A cylindrical phantom (φ80x120 mm) holds inserts for PET/CT scanning...
August 2, 2017: Medical Physics
https://www.readbyqxmd.com/read/28765192/four-dimensional-ct-guided-transcatheter-removal-of-a-fractured-migrated-catheter-of-a-totally-implantable-venous-access-port
#5
Kazushi Fujimoto, Hajime Kasai, Toshihiko Sugiura, Koichiro Tatsumi
Patients undergoing chemotherapy usually undergo placement of a totally implantable venous access port (TIVAP), but TIVAP catheter fracture is rare. We encountered a case where flushing the TIVAP catheter became impossible because of resistance. A 61-year-old-woman underwent TIVAP placement. Although a chest X-ray revealed the fractured catheter had migrated into the right hilar area, the timing of the fracture was unclear. Four-dimensional computed tomography (4D-CT) showed that the tip of the fractured catheter was located at the anterior segmental artery of the right upper lobe and was immobile, with the remaining portion flapping with the blood flow...
August 1, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28746180/a-consort-compliant-prospective-randomized-controlled-trial-radiation-dose-reducing-in-computed-tomography-using-an-additional-lateral-scout-view-combined-with-automatic-tube-current-modulation-phantom-and-patient-study
#6
RANDOMIZED CONTROLLED TRIAL
Wanlin Peng, Zhenlin Li, Chunchao Xia, Yingkun Guo, Jinge Zhang, Kai Zhang, Lei Li, Fei Zhao
BACKGROUND: Radiation exposure has been a hot point in research field of computed tomography (CT). Recently, automated tube current modulation (ATCM) has emerged as an important technique to reduce radiation exposure. Many studies have shown that the difference in scout view would affect modulation. This prospective randomized controlled study is aimed to investigate the impact of an additional lateral scout view on radiation dose and image quality in CT using ACTM. METHODS: Combined with ATCM (Care Dose 4D) on multidetector CT, 2 thoracic phantom CT image series were acquired in which planning was conducted with either an anteroposterior (AP) or an AP-lateral scout view...
July 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28741786/ectopic-parathyroid-adenoma-in-the-pyriform-sinus
#7
Jonathan Kim, Maricel Cubangbang, Lacey Adkins, Stanley Chia, Timothy R DeKlotz, Lisa Boyle, Bruce Davidson
BACKGROUND: Ectopic parathyroid glands may complicate the surgical approach to primary hyperparathyroidism. We describe a rare ectopic parathyroid location, the pyriform sinus. METHODS: Three patients, 2 after prior unsuccessful parathyroid exploration, were found to have ectopic parathyroid adenomas in the pyriform sinus. Two cases were identified by 4D-CT of the neck. The other was localized by a technetium 99m sestamibi single photon emission CT (SPECT). In each case, office endoscopy confirmed the lesions...
July 25, 2017: Head & Neck
https://www.readbyqxmd.com/read/28740930/functional-image-guided-radiation-therapy-planning-in-volumetric-modulated-arc-therapy-for-patients-with-malignant-pleural-mesothelioma
#8
Yoshiko Doi, Tomoki Kimura, Takeo Nakashima, Yuki Takeuchi, Ippei Takahashi, Ikuno Nishibuchi, Yuji Murakami, Yasushi Nagata
PURPOSE: To investigate the incorporation of functional lung image-derived low-attenuation area (LAA) based on 4-dimensional computed tomography (4D-CT) in volumetric modulated arc therapy (VMAT) planning for patients with malignant pleural mesothelioma (MPM) after extrapleural pneumonectomy. METHODS AND MATERIALS: Twelve patients with MPM after extrapleural pneumonectomy were included. The primarily affected side was the right in 6 patients and the left in 6 patients...
April 2017: Advances in Radiation Oncology
https://www.readbyqxmd.com/read/28740918/impact-of-moving-target-on-measurement-accuracy-in-3d-and-4d-pet-imaging-a-phantom-study
#9
Yunfeng Cui, James Bowsher, Jing Cai, Fang-Fang Yin
PURPOSE: The purpose of this study was to evaluate the impact of tumor motion on maximum standardized uptake value (SUVmax) and metabolic tumor volume (MTV) measurements in both 3-dimensional and respiratory-correlated, 4-dimensional positron emission tomography (PET) imaging. We also evaluated the effect of implementing different attenuation correction methods in 4-dimensional PET image reconstruction on SUVmax and MTV. METHODS AND MATERIALS: An anthropomorphic thorax phantom with a spherical ball as a surrogate for a tumor was used...
January 2017: Advances in Radiation Oncology
https://www.readbyqxmd.com/read/28726684/low-dose-4d-cone-beam-ct-via-joint-spatiotemporal-regularization-of-tensor-framelet-and-nonlocal-total-variation
#10
Hao Han, Hao Gao, Lei Xing
Excessive radiation exposure is still a major concern in 4D cone-beam computed tomography (4D-CBCT) due to its prolonged scanning duration. Radiation dose can be effectively reduced by either under-sampling the x-ray projections or reducing the x-ray flux. However, 4D-CBCT reconstruction under such low-dose protocols is prone to image artifacts and noise. In this work, we propose a novel joint regularization-based iterative reconstruction method for low-dose 4D-CBCT. To tackle the under-sampling problem, we employ spatiotemporal tensor framelet (STF) regularization to take advantage of the spatiotemporal coherence of the patient anatomy in 4D images...
July 20, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28715346/new-prospective-4d-ct-for-mitigating-the-effects-of-irregular-respiratory-motion
#11
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
#12
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
#13
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
#14
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
#15
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
#16
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
#17
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
#18
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
#19
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
#20
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
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