keyword
MENU ▼
Read by QxMD icon Read
search

Contouring radiotherapy

keyword
https://www.readbyqxmd.com/read/28543069/real-time-dynamic-mr-image-reconstruction-using-compressed-sensing-and-principal-component-analysis-cs-pca-demonstration-in-lung-tumor-tracking
#1
Bryson Dietz, Eugene Yip, Jihyun Yun, B Gino Fallone, Keith Wachowicz
PURPOSE: This work presents a real-time dynamic image reconstruction technique, that combines compressed sensing and principal component analysis (CS-PCA), to achieve real-time adaptive radiotherapy with the use of a linac-magnetic resonance imaging system. METHODS: Six retrospective fully sampled dynamic data sets of patients diagnosed with non-small cell lung cancer were used to investigate the CS-PCA algorithm. Using a database of fully sampled k-space, principal components (PC's) were calculated to aid in the reconstruction of undersampled images...
May 19, 2017: Medical Physics
https://www.readbyqxmd.com/read/28534430/variability-in-axillary-lymph-node-delineation-for-breast-cancer-radiotherapy-in-presence-of-guidelines-on-a-multi-institutional-platform
#2
Delia Ciardo, Angela Argenone, Genoveva Ionela Boboc, Francesca Cucciarelli, Fiorenza De Rose, Maria Carmen De Santis, Alessandra Huscher, Edy Ippolito, Maria Rosa La Porta, Lorenza Marino, Ilaria Meaglia, Isabella Palumbo, Francesca Rossi, Paolo Alpi, Mario Bignardi, Alessio Bonanni, Domenico Cante, Tino Ceschia, Letizia Fabbietti, Marco Lupattelli, Elisa Donatella Mantero, Alessia Monaco, Patrizia Porcu, Vincenzo Ravo, Sonia Silipigni, Angelo Tozzi, Vincenza Umina, Dario Zerini, Luigi Bordonaro, Giorgia Capezzali, Elena Clerici, Sarah Pia Colangione, Michela Dispinzieri, Jessica Dognini, Laura Donadoni, Sara Falivene, Alessandra Fozza, Barbara Grilli, Roberta Guarnaccia, Eva Iannacone, Valentina Lancellotta, Agnese Prisco, Rosalinda Ricotti, Roberto Orecchia, Barbara Alicja Jereczek-Fossa, Maria Cristina Leonardi
AIM: To quantify the variability between radiation oncologists (ROs) when outlining axillary nodes in breast cancer. MATERIAL AND METHODS: For each participating center, three ROs with different levels of expertise, i.e., junior (J), senior (S) and expert (E), contoured axillary nodal levels (L1, L2, L3 and L4) on the CT images of three different patients (P) of an increasing degree of anatomical complexity (from P1 to P2 to P3), according to contouring guidelines...
May 23, 2017: Acta Oncologica
https://www.readbyqxmd.com/read/28533050/dual-core-steered-non-rigid-registration-for-multi-modal-images-via-bi-directional-image-synthesis
#3
Xiaohuan Cao, Jianhua Yang, Yaozong Gao, Yanrong Guo, Guorong Wu, Dinggang Shen
In prostate cancer radiotherapy, computed tomography (CT) is widely used for dose planning purposes. However, because CT has low soft tissue contrast, it makes manual contouring difficult for major pelvic organs. In contrast, magnetic resonance imaging (MRI) provides high soft tissue contrast, which makes it ideal for accurate manual contouring. Therefore, the contouring accuracy on CT can be significantly improved if the contours in MRI can be mapped to CT domain by registering MRI with CT of the same subject, which would eventually lead to high treatment efficacy...
May 13, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28532608/assessment-of-the-novel-online-delineation-workshop-dummy-run-approach-using-falcon-within-a-european-multicentre-trial-in-cervical-cancer-raids
#4
Eleonor Rivin Del Campo, Sofia Rivera, María Martínez-Paredes, Philippe Hupé, Andrea Slocker Escarpa, Isabelle Borget, Renaud Mazeron, Suzy Scholl, Amalia Palacios Eito, Christine Haie-Meder, Cyrus Chargari, Eric Deutsch
BACKGROUND AND PURPOSE: Online delineation workshops (ODW) permit training of geographically dispersed participants. The purpose is to evaluate the methodology of an ODW using FALCON to harmonize delineation within a European multicentre trial on locally advanced cervical cancer (LACC). MATERIAL AND METHODS: Two ODW included 46 clinicians (14 centres). Clinicians completed baseline (C1), guideline (C2) and final contours (C3) for external beam radiotherapy (EBRT) and brachytherapy (BT) for LACC...
May 19, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28510808/development-of-a-contouring-guide-in-three-different-head-set-ups-for-hippocampal-sparing-radiotherapy-a-practical-approach
#5
Saide Di Biase, Marianna Trignani, Luciana Caravatta, Paul Ioan Voicu, Clelia Di Carlo, Annamaria Vinciguerra, Antonietta Augurio, Francesca Perrotti, Valentina Panara, Domenico Genovesi
BACKGROUNDS: Irradiation of the hippocampus plays a role in neurocognitive toxicity. Its delineation is complex and in practice different head position can vary hippocampus morphology on axial images; so atlas in a single standard position can result ineffective to describe different hippocampal morphologies in different head set-up. The purpose of our study was to develop a guide based on magnetic resonance imaging for hippocampus delineation in three different head set-ups. MATERIALS AND METHODS: Three patients were selected to elaborate our guide...
May 16, 2017: La Radiologia Medica
https://www.readbyqxmd.com/read/28493295/towards-ultrasound-guided-adaptive-radiotherapy-for-cervical-cancer-evaluation-of-elekta-s-semi-automated-uterine-segmentation-method-on-3d-ultrasound-images
#6
Sarah A Mason, Tuathan P O'Shea, Ingrid M White, Susan Lalondrelle, Kate Downey, Mariwan Baker, Claus F Behrens, Jeffrey C Bamber, Emma J Harris
PURPOSE: 3D ultrasound (US) images of the uterus may be used to adapt radiotherapy (RT) for cervical cancer patients based on changes in daily anatomy. This requires accurate on-line segmentation of the uterus. The aim of this work was to assess the accuracy of Elekta's "Assisted Gyne Segmentation" (AGS) algorithm in semi-automatically segmenting the uterus on 3D transabdominal ultrasound images by comparison with manual contours. MATERIALS & METHODS: Nine patients receiving RT for cervical cancer were imaged with the 3D Clarity(®) transabdominal probe at RT planning, and 1 to 7 times during treatment...
May 10, 2017: Medical Physics
https://www.readbyqxmd.com/read/28480870/regional-deep-hyperthermia-impact-of-observer-variability-in-ct-based-manual-tissue-segmentation-on-simulated-temperature-distribution
#7
Bassim Aklan, Josefin Hartmann, Diana Zink, Hadi Siavooshhaghighi, Ricarda Merten, Florian Putz, Oliver Ott, Rainer Fietkau, Christoph Bert
The aim of this study was to systematically investigate the influence of the inter- and intra-observer segmentation variation of tumors and organs at risk on the simulated temperature coverage of the target. CT scans of six patients with tumors in the pelvic region acquired for radiotherapy treatment planning were used for hyperthermia treatment planning. To study the effect of inter-observer variation, three observers manually segmented in the CT images of each patient the following structures: fat, muscle, bone and the bladder...
May 8, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28478912/quality-assurance-of-radiotherapy-in-the-ongoing-eortc-1219-dahanca-29-trial-for-hpv-p16-negative-squamous-cell-carcinoma-of-the-head-and-neck-results-of-the-benchmark-case-procedure
#8
Melissa Christiaens, Sandra Collette, Jens Overgaard, Vincent Gregoire, Joanna Kazmierska, Pierre Castadot, Jordi Giralt, Warren Grant, Milan Tomsej, Raquel Bar-Deroma, Angelo F Monti, Coen Wilhelm Hurkmans, Damien Charles Weber
BACKGROUND AND PURPOSE: The phase III EORTC 1219-DAHANCA 29 intergroup trial evaluates the influence of nimorazole in patients with locally advanced head and neck cancer when treated with accelerated radiotherapy (RT) in combination with chemotherapy. This article describes the results of the RT Benchmark Case (BC) performed before patient inclusion. MATERIALS AND METHODS: The participating centers were asked to perform a 2-step BC, consisting of (1) a delineation and (2) a planning exercise according to the protocol guidelines...
May 4, 2017: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
https://www.readbyqxmd.com/read/28477340/a-neural-network-approach-for-fast-automated-quantification-of-dir-performance
#9
John Neylon, Yugang Min, Daniel A Low, Anand Santhanam
PURPOSE: A critical step in adaptive radiotherapy (ART) workflow is deformably registering the simulation CT with the daily or weekly volumetric imaging. Quantifying the deformable image registration accuracy under these circumstances is a complex task due to the lack of known ground-truth landmark correspondences between the source data and target data. Generating landmarks manually (using experts) is time-consuming, and limited by image quality and observer variability. While image similarity metrics (ISM) may be used as an alternative approach to quantify the registration error, there is a need to characterize the ISM values by developing a non-linear cost function and translate them to physical distance measures in order to enable fast, quantitative comparison of registration performance...
May 5, 2017: Medical Physics
https://www.readbyqxmd.com/read/28469512/does-motion-assessment-with-4-dimensional-computed-tomographic-imaging-for-non-small-cell-lung-cancer-radiotherapy-improve-target-volume-coverage
#10
Naseer Ahmed, Sankar Venkataraman, Kate Johnson, Keith Sutherland, Shaun K Loewen
INTRODUCTION: Modern radiotherapy with 4-dimensional computed tomographic (4D-CT) image acquisition for non-small cell lung cancer (NSCLC) captures respiratory-mediated tumor motion to provide more accurate target delineation. This study compares conventional 3-dimensional (3D) conformal radiotherapy (3DCRT) plans generated with standard helical free-breathing CT (FBCT) with plans generated on 4D-CT contoured volumes to determine whether target volume coverage is affected. MATERIALS AND METHODS: Fifteen patients with stage I to IV NSCLC were enrolled in the study...
2017: Clinical Medicine Insights. Oncology
https://www.readbyqxmd.com/read/28466444/a-pilot-study-on-geometrical-uncertainties-for-intra-ocular-cancers-in-radiotherapy
#11
Rachitha Antony, Alan Herschtal, Stephen Todd, Claire Phillips, Annette Haworth
A system for stabilising and monitoring eye movements for linac-based stereotactic radiotherapy associated with the mobile eye, the Eye Tracker, was developed. Whilst the Eye Tracker design is based on a previously reported system, the purpose of this study was to confirm that the modified version can be used with clinically acceptable treatment margins. We report the estimates of the margin required to account for inter- and intra-fraction eye motion based on data from 12 consecutive patients treated with the Eye Tracker system in place...
May 2, 2017: Australasian Physical & Engineering Sciences in Medicine
https://www.readbyqxmd.com/read/28466154/spinal-cord-constraints-in-the-era-of-high-precision-radiotherapy-retrospective-analysis-of-62%C3%A2-spinal-paraspinal-lesions-with-possible-infringements-of-spinal-cord-constraints-within-a%C3%A2-minimal-volume
#12
Sebastian Zschaeck, Peter Wust, Reinhold Graf, Waldemar Wlodarczyk, Reinhard Schild, Alexander Henry Thieme, Mirko Weihrauch, Volker Budach, Pirus Ghadjar
OBJECTIVE: Current constraints aim to minimize the risk of radiation myelitis by the use of restrictive maximal spinal cord doses, commonly 50 Gy. However, several studies suggested that a dose-volume effect could exist. Based on these observations, we evaluated patients receiving potentially excessive doses to the spinal cord within minimal volumes. PATIENTS AND METHODS: Patients receiving radiotherapy between June 2010 and May 2015 using the Novalis(TM) (Varian, Palo Alto, CA, USA; Brainlab, Heimstetten, Germany) radiosurgery system were retrospectively analyzed...
May 2, 2017: Strahlentherapie und Onkologie: Organ der Deutschen Röntgengesellschaft ... [et Al]
https://www.readbyqxmd.com/read/28464749/contouring-and-dose-calculation-in-head-and-neck-cancer-radiotherapy-after-reduction-of-metal-artifacts-in-ct-images
#13
Christian Rønn Hansen, Rasmus Lübeck Christiansen, Ebbe Laugaard Lorenzen, Anders Smedegaard Bertelsen, Jon Thor Asmussen, Niels Gyldenkerne, Jesper Grau Eriksen, Jørgen Johansen, Carsten Brink
BACKGROUND: Delineation accuracy of the gross tumor volume (GTV) in radiotherapy planning for head and neck (H&N) cancer is affected by computed tomography (CT) artifacts from metal implants which obscure identification of tumor as well as organs at risk (OAR). This study investigates the impact of metal artifact reduction (MAR) in H&N patients in terms of delineation consistency and dose calculation precision in radiation treatment planning. MATERIAL AND METHODS: Tumor and OAR delineations were evaluated in planning CT scans of eleven oropharynx patients with streaking artifacts in the tumor region preceding curative radiotherapy (RT)...
June 2017: Acta Oncologica
https://www.readbyqxmd.com/read/28462689/intensity-modulated-radiation-therapy-improves-the-target-coverage-over-3-d-planning-while-meeting-lung-tolerance-doses-for-all-patients-with-malignant-pleural-mesothelioma
#14
Sukran Ulger, Eren Cetin, Serap Catli, Hilal Sarac, Diclehan Kilic, Huseyin Bora
PURPOSE: To investigate high conformality on target coverage and the ability on creating strict lung dose limitation of intensity-modulated radiation therapy in malignant pleural mesothelioma. PATIENTS AND METHODS: Twenty-four radiation therapy plannings were evaluated and compared with dosimetric outcomes of conformal radiation therapy and intensity-modulated radiation therapy. Hemithoracal radiation therapy was performed on 12 patients with a fraction of 1.8 Gy to a total dose of 50...
June 2017: Technology in Cancer Research & Treatment
https://www.readbyqxmd.com/read/28461787/dosimetric-impact-in-the-dose-volume-histograms-of-rectal-and-vesical-wall-contouring-in-prostate-cancer-imrt-treatments
#15
Laura Gómez, Carlos Andrés, Antonio Ruiz
AIM: The main purpose of this study was to evaluate the differences in dose-volume histograms of IMRT treatments for prostate cancer based on the delineation of the main organs at risk (rectum and bladder) as solid organs or by contouring their wall. BACKGROUND: Rectum and bladder have typically been delineated as solid organs, including the waste material, which, in practice, can lead to an erroneous assessment of the risk of adverse effects. MATERIALS AND METHODS: A retrospective study was made on 25 patients treated with IMRT radiotherapy for prostate adenocarcinoma...
May 2017: Reports of Practical Oncology and Radiotherapy
https://www.readbyqxmd.com/read/28453537/an-efficient-and-robust-mri-guided-radiotherapy-planning-approach-for-targeting-abdominal-organs-and-tumours-in-the-mouse
#16
Veerle Kersemans, John S Beech, Stuart Gilchrist, Paul Kinchesh, Philip D Allen, James Thompson, Ana L Gomes, Zenobia D'Costa, Luke Bird, Iain D C Tullis, Robert G Newman, Aurelien Corroyer-Dulmont, Nadia Falzone, Abul Azad, Katherine A Vallis, Owen J Sansom, Ruth J Muschel, Borivoj Vojnovic, Mark A Hill, Emmanouil Fokas, Sean C Smart
INTRODUCTION: Preclinical CT-guided radiotherapy platforms are increasingly used but the CT images are characterized by poor soft tissue contrast. The aim of this study was to develop a robust and accurate method of MRI-guided radiotherapy (MR-IGRT) delivery to abdominal targets in the mouse. METHODS: A multimodality cradle was developed for providing subject immobilisation and its performance was evaluated. Whilst CT was still used for dose calculations, target identification was based on MRI...
2017: PloS One
https://www.readbyqxmd.com/read/28433482/variations-of-target-volume-definition-and-daily-target-volume-localization-in-stereotactic-body-radiotherapy-for-early-stage-non-small-cell-lung-cancer-patients-under-abdominal-compression
#17
Chunhui Han, Sagus Sampath, Timothy E Schultheisss, Jeffrey Y C Wong
We aimed to compare gross tumor volumes (GTV) in 3-dimensional computed tomography (3DCT) simulation and daily cone beam CT (CBCT) with the internal target volume (ITV) in 4-dimensional CT (4DCT) simulation in stereotactic body radiotherapy (SBRT) treatment of patients with early-stage non-small cell lung cancer (NSCLC) under abdominal compression. We retrospectively selected 10 patients with NSCLC who received image-guided SBRT treatments under abdominal compression with daily CBCT imaging. GTVs were contoured as visible gross tumor on the planning 3DCT and daily CBCT, and ITVs were contoured using maximum intensity projection (MIP) images of the planning 4DCT...
April 19, 2017: Medical Dosimetry: Official Journal of the American Association of Medical Dosimetrists
https://www.readbyqxmd.com/read/28419246/quality-assurance-for-a-multicenter-phase-ii-study-of-stereotactic-ablative-radiotherapy-for-hepatocellular-carcinoma-%C3%A2-5-cm-a-planning-dummy-run
#18
Sun Hyun Bae, Mi-Sook Kim, Won Il Jang, Kum Bae Kim, Kwang Hwan Cho, Woo Chul Kim, Chang Yeol Lee, Eun Seog Kim, Chul Won Choi, A Ram Chang, Sunmi Jo, Jin-Young Kim
Objective: The Korean Radiation Oncology Group (12-02) investigated the outcome of stereotactic ablative radiotherapy for hepatocellular carcinoma ≤5 cm using 60 Gy in three fractions. To evaluate dosimetric differences and compliance in a multicenter trial, a planning dummy run procedure was performed. Methods: All six participating institutions were provided the contours of two dummy run cases. Plans were performed following the study protocol to cover the planning target volume with a minimum of 90% of the prescription dose and to satisfy the constraints for organs at risk...
April 13, 2017: Japanese Journal of Clinical Oncology
https://www.readbyqxmd.com/read/28414799/comprehensive-evaluation-of-ten-deformable-image-registration-algorithms-for-contour-propagation-between-ct-and-cone-beam-ct-images-in-adaptive-head-neck-radiotherapy
#19
Xin Li, Yuyu Zhang, Yinghua Shi, Shuyu Wu, Yang Xiao, Xuejun Gu, Xin Zhen, Linghong Zhou
Deformable image registration (DIR) is a critical technic in adaptive radiotherapy (ART) for propagating contours between planning computerized tomography (CT) images and treatment CT/cone-beam CT (CBCT) images to account for organ deformation for treatment re-planning. To validate the ability and accuracy of DIR algorithms in organ at risk (OAR) contour mapping, ten intensity-based DIR strategies, which were classified into four categories-optical flow-based, demons-based, level-set-based and spline-based-were tested on planning CT and fractional CBCT images acquired from twenty-one head & neck (H&N) cancer patients who underwent 6~7-week intensity-modulated radiation therapy (IMRT)...
2017: PloS One
https://www.readbyqxmd.com/read/28410685/evaluation-of-mesh-and-binary-based-contour-propagation-methods-in-4d-thoracic-radiotherapy-treatments-using-patient-4d-ct-images
#20
Yuanyuan Ma, Xinguo Liu, Zhongying Dai, Pengbo He, Yuanlin Yan, Guosheng Shen, Ping Yuan, Qiang Li
Based on four dimensional (4D) computed tomography (CT) images, mesh- and binary-based contour propagation algorithms for 4D thoracic radiotherapy treatments were evaluated. Gross tumor volumes (GTVs), lungs, hearts and spinal cords on the CT images at the end-exhale and end-inhale phases for six patients were delineated by the physician. All volumes of interest (VOIs) were automatically propagated from the end-exhale phase to the end-inhale phase using two propagation methods. The propagated VOIs were quantitatively compared with the VOIs contoured at the end-inhale phase by the physician using Dice Similarity Coefficient (DSC), Mean Slicewise Hausdorff Distance (MSHD), Center Of Mass (COM) displacement and volume difference...
April 2017: Physica Medica: PM
keyword
keyword
90457
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"