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https://www.readbyqxmd.com/read/28081014/canny-edge-based-deformable-image-registration
#1
Vasant Kearney, Yihui Huang, Weihua Mao, Baohong Yuan, Liping Tang
This work focuses on developing a 2D Canny edge-based deformable image registration (Canny DIR) algorithm to register in vivo white light images taken at various time points. This method uses a sparse interpolation deformation algorithm to sparsely register regions of the image with strong edge information. A stability criterion is enforced which removes regions of edges that do not deform in a smooth uniform manner. Using a synthetic mouse surface ground truth model, the accuracy of the Canny DIR algorithm was evaluated under axial rotation in the presence of deformation...
February 7, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28072693/comparative-evaluation-of-target-volumes-defined-by-deformable-and-rigid-registration-of-diagnostic-pet-ct-to-planning-ct-in-primary-esophageal-cancer
#2
Yanluan Guo, Jianbin Li, Peng Zhang, Qian Shao, Min Xu, Yankang Li
BACKGROUND: To evaluate the geometrical differences of target volumes propagated by deformable image registration (DIR) and rigid image registration (RIR) to assist target volume delineation between diagnostic Positron emission tomography/computed tomography (PET/CT) and planning CT for primary esophageal cancer (EC). METHODS: Twenty-five patients with EC sequentially underwent a diagnostic F-fluorodeoxyglucose (F-FDG) PET/CT scan and planning CT simulation. Only 19 patients with maximum standardized uptake value (SUVmax) ≥ 2...
January 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28072395/evaluation-of-adaptive-treatment-planning-for-patients-with-non-small-cell-lung-cancer
#3
Hualiang Zhong, Salim Siddiqui, Benjamin Movsas, Indrin Chetty
The purpose of this study was to develop metrics to evaluate uncertainties in deformable dose accumulation (DDA) for patients with non-small cell lung cancer (NSCLC). Initial treatment plans (primary) and cone-beam CT (CBCT) images were retrospectively processed for seven NSCLC patients, who showed significant tumor regression during the course of treatment. Each plan was developed with IMRT for 2 Gy��33 fractions. A B-spline-based DIR algorithm was used to register weekly CBCT images to a reference image acquired at fraction 21 and the resultant displacement vector fields (DVFs) were then modified using a finite element method (FEM)...
January 10, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28069552/longitudinal-monitoring-of-skin-accumulation-of-nanocarriers-and-biologicals-with-fiber-optic-near-infrared-fluorescence-spectroscopy-fonirs
#4
James I Griffin, Michael J Benchimol, Dmitri Simberg
Systemically injected drug delivery systems distribute into various organs and tissues, including liver, spleen and kidneys. Recent reports pointed out a significant accumulation of systemically injected nanoparticles in the skin. Skin constitutes the largest organ in the body with important immune functions, and accumulation of drug delivery systems could have significant implications for skin toxicity in living subjects. Fiber optic-based near-infrared spectroscopy (FONIRS) setup was developed and tested for measuring of NIR (760nm excitation) emission spectra in the skin...
January 6, 2017: Journal of Controlled Release: Official Journal of the Controlled Release Society
https://www.readbyqxmd.com/read/28058533/the-numerical-stability-of-transformation-based-ct-ventilation
#5
Edward Castillo, Richard Castillo, Yevgeniy Vinogradskiy, Thomas Guerrero
: Computed tomography (CT)-derived ventilation imaging utilizes deformable image registration (DIR) to recover respiratory-induced tissue volume changes from inhale/exhale 4DCT phases. While current strategies for validating CT ventilation rely on analyzing its correlation with existing functional imaging modalities, the numerical stability of the CT ventilation calculation has not been characterized. PURPOSE: The purpose of this study is to examine how small changes in the DIR displacement field can affect the calculation of transformation-based CT ventilation...
January 5, 2017: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/28048860/su-f-p-54-guidelines-to-check-image-registration-qa-of-a-clinical-deformation-registration-software-a-single-institution-preliminary-study
#6
G Gill, S Souri, A Rea, Y Chen, J Antone, X Qian, A Riegel, P Taylor, M Marrero, F Diaz, Y Cao, A Jamshidi, S Barley, V Sorell, G Karangelis, T Button, E Klein
PURPOSE: The objective of this study is to verify and analyze the accuracy of a clinical deformable image registration (DIR) software. METHODS: To test clinical DIR software qualitatively and quantitatively, we focused on lung radiotherapy and analyzed a single (Lung) patient CT scan. Artificial anatomical changes were applied to account for daily variations during the course of treatment including the planning target volume (PTV) and organs at risk (OAR). The primary CT (pCT) and the structure set (pST) was deformed with commercial tool (ImSimQA-Oncology Systems Limited) and after artificial deformation (dCT and dST) sent to another commercial tool (VelocityAI-Varian Medical Systems)...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048843/su-f-j-134-evaluation-of-deformation-field-accuracy-using-regional-rigid-registrations-with-variable-size
#7
E Ahunbay, X Li
PURPOSE: How to quickly assess the uncertainty in the Deformation Field (DF) generated from Deformable Image Registration (DIR) over the imaged anatomy is a major issue. Here we introduce a method to determine the DF uncertainty using local rigid registrations of varying box size. METHODS: A series of 6-degree rigid registrations are performed with a cubic ROI centered on the voxel of the interest. The size of the registration box is varied from a large value, e...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048834/th-ef-bra-03-assessment-of-data-driven-respiratory-motion-compensation-methods-for-4d-cbct-image-registration-and-reconstruction-using-clinical-datasets
#8
M J Riblett, E Weiss, G E Christensen, G D Hugo
PURPOSE: To evaluate the performance of a 4D-CBCT registration and reconstruction method that corrects for respiratory motion and enhances image quality under clinically relevant conditions. METHODS: Building on previous work, which tested feasibility of a motion-compensation workflow using image datasets superior to clinical acquisitions, this study assesses workflow performance under clinical conditions in terms of image quality improvement. Evaluated workflows utilized a combination of groupwise deformable image registration (DIR) and image reconstruction...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048798/su-f-j-88-comparison-of-two-deformable-image-registration-algorithms-for-ct-to-ct-contour-propagation
#9
A Gopal, H Xu, S Chen
PURPOSE: To compare the contour propagation accuracy of two deformable image registration (DIR) algorithms in the Raystation treatment planning system - the "Hybrid" algorithm based on image intensities and anatomical information; and the "Biomechanical" algorithm based on linear anatomical elasticity and finite element modeling. METHODS: Both DIR algorithms were used for CT-to-CT deformation for 20 lung radiation therapy patients that underwent treatment plan revisions...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048776/su-f-j-77-variations-in-the-displacement-vector-fields-calculated-by-different-deformable-image-registration-algorithms-used-in-helical-axial-and-cone-beam-ct-images-of-a-mobile
#10
I Ali, J Jaskowiak, N Alsbou, S Ahmad
PURPOSE: To investigate quantitatively the displacement-vector-fields (DVF) obtained from different deformable image registration algorithms (DIR) in helical (HCT), axial (ACT) and cone-beam CT (CBCT) to register CT images of a mobile phantom and its correlation with motion amplitudes and frequencies. METHODS: HCT, ACT and CBCT are used to image a mobile phantom which includes three targets with different sizes that are manufactured from water-equivalent material and embedded in low density foam...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048724/su-f-j-84-comparison-of-quantitative-deformable-image-registration-evaluation-tools-application-to-prostate-igart
#11
N Dogan, E Weiss, W Sleeman, G Christensen, J Williamson, J Ford
PURPOSE: Errors in displacement vector fields (DVFs) generated by Deformable Image Registration (DIR) algorithms can give rise to significant uncertainties in contour propagation and dose accumulation in Image-Guided Adaptive Radiotherapy (IGART). The purpose of this work is to assess the accuracy of two DIR algorithms using a variety of quality metrics for prostate IGART. METHODS: Pelvic CT images were selected from an anonymized database of nineteen prostate patients who underwent 8-12 serial scans during radiotherapy...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048720/tu-ab-202-05-gpu-based-4d-deformable-image-registration-using-adaptive-tetrahedral-mesh-modeling
#12
Z Zhong, L Zhuang, X Gu, J Wang, H Chen, X Zhen
PURPOSE: Deformable image registration (DIR) has been employed today as an automated and effective segmentation method to transfer tumor or organ contours from the planning image to daily images, instead of manual segmentation. However, the computational time and accuracy of current DIR approaches are still insufficient for online adaptive radiation therapy (ART), which requires real-time and high-quality image segmentation, especially in a large datasets of 4D-CT images. The objective of this work is to propose a new DIR algorithm, with fast computational speed and high accuracy, by using adaptive feature-based tetrahedral meshing and GPU-based parallelization...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048707/mo-fg-campus-jep1-05-water-equivalent-path-length-calculations-using-scatter-corrected-head-and-neck-cbct-images-to-evaluate-patients-for-adaptive-proton-therapy
#13
J Kim, Y Park, G Sharp, B Winey
PURPOSE: To establish a method to evaluate the dosimetric impact of anatomic changes in head and neck patients during proton therapy by using scatter-corrected cone-beam CT (CBCT) images. METHODS: The water equivalent path length (WEPL) was calculated to the distal edge of PTV contours by using tomographic images available for six head and neck patients received photon therapy. The proton range variation was measured by calculating the difference between the distal WEPLs calculated with the planning CT and weekly treatment CBCT images...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048668/tu-ab-202-01-multi-institutional-validation-study-of-commercially-available-deformable-image-registration-software-for-thoracic-images
#14
N Kadoya, Y Nakajima, M Saito, Y Miyabe, M Kurooka, S Kito, M Sasaki, Y Fujita, K Arai, K Tani, M Yagi, A Wakita, N Tohyama, K Jingu
PURPOSE: The purpose of this study was to assess the accuracy of commercially available deformable image registration (DIR) software for thoracic images on multi-institution. Furthermore, we determined the variation in the DIR accuracy among institutions due to different DIR algorithms and DIR procedures. METHODS: Thoracic four-dimensional (4D) CT images of ten patients with esophagus or lung cancer were used. Datasets for these patients were provided by DIR-lab (dir-lab...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048653/tu-h-campus-jep1-01-characterization-of-a-parameterized-image-similarity-cost-function-for-automated-patient-and-site-specific-dir-accuracy-optimizations
#15
J Neylon, Y Min, K Hasse, D Low, A Santhanam
PURPOSE: Clinical deformable image registration (DIR) accuracy is difficult to quantify, making validation and verification manual and time consuming. It has also been seen that DIR accuracy can be improved by patient and site specific optimization. We previously investigated a cost function to parameterize image similarity metrics (ISMs) and provide a quantifiable comparison of DIR performance. In this abstract, we characterize and optimize the cost function response (CFR) and correlation to target registration error (TRE) in a dense registration parameter space...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048615/tu-h-202-04-the-vampire-challenge-preliminary-results-from-a-multi-institutional-study-of-ct-ventilation-image-accuracy
#16
J Kipritidis
: CT ventilation imaging is an exciting functional imaging modality that combines four-dimensional computed tomography (4DCT) and deformable image registration (DIR) to provide exquisite ventilation maps of the lung. CT ventilation imaging can be used for: (1) Functional avoidance in thoracic radiation therapy, (2) Imaging longitudinal changes in regional lung function for treatment assessment and adaptation, (3) Image-assisted diagnosis of non-oncologic respiratory diseases. CT ventilation imaging uses CT, a predominantly anatomic imaging modality, and through imaging processing creates functional images...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048567/su-c-bra-07-variability-of-patient-specific-motion-models-derived-using-different-deformable-image-registration-algorithms-for-lung-cancer-stereotactic-body-radiotherapy-sbrt-patients
#17
S Dhou, D Ionascu, J Lewis, C Williams
PURPOSE: To study the variability of patient-specific motion models derived from 4-dimensional CT (4DCT) images using different deformable image registration (DIR) algorithms for lung cancer stereotactic body radiotherapy (SBRT) patients. METHODS: Motion models are derived by 1) applying DIR between each 4DCT image and a reference image, resulting in a set of displacement vector fields (DVFs), and 2) performing principal component analysis (PCA) on the DVFs, resulting in a motion model (a set of eigenvectors capturing the variations in the DVFs)...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048560/tu-h-campus-jep1-04-deformable-image-registration-performances-in-pelvis-patients-impact-of-cbct-image-quality
#18
M Fusella, G Loi, C Fiandra, E Lanzi
PURPOSE: To investigate the accuracy and robustness, against image noise and artifacts (typical of CBCT images), of a commercial algorithm for deformable image registration (DIR), to propagate regions of interest (ROIs) in computational phantoms based on real prostate patient images. METHODS: The Anaconda DIR algorithm, implemented in RayStation was tested. Two specific Deformation Vector Fields (DVFs) were applied to the reference data set (CTref) using the ImSimQA software, obtaining two deformed CTs...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048559/we-ab-202-05-validation-of-lung-stress-maps-for-ct-ventilation-imaging
#19
G Cazoulat, J Kipritidis, S Siva, M Hofman, S Jolly, M Matuszak, J Balter, P Keall, K Brock
PURPOSE: To date, lung CT-ventilation imaging has been based on quantification of local breathing-induced changes in Hounsfield Units (HU) or volume. This work investigates the use of a stress map resulting from a biomechanical deformable image registration (DIR) algorithm as a metric of the ventilation function. METHOD: Eight lung cancer patients presenting different kinds of ventilation defects were retrospectively analyzed. Additionally, to the 4DCT acquired for radiotherapy planning, five of them had PET and three had SPECT imaging following inhalation of Ga-68 and Tc-99m, respectively...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28048557/tu-h-202-00-ct-ventilation-imaging-the-new-clinical-reality-of-functional-avoidance-and-response-assessment-in-lung-cancer-radiation-therapy
#20
Paul Keall
: CT ventilation imaging is an exciting functional imaging modality that combines four-dimensional computed tomography (4DCT) and deformable image registration (DIR) to provide exquisite ventilation maps of the lung. CT ventilation imaging can be used for: (1) Functional avoidance in thoracic radiation therapy, (2) Imaging longitudinal changes in regional lung function for treatment assessment and adaptation, (3) Image-assisted diagnosis of non-oncologic respiratory diseases. CT ventilation imaging uses CT, a predominantly anatomic imaging modality, and through imaging processing creates functional images...
June 2016: Medical Physics
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