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Deformable Image Registration

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https://www.readbyqxmd.com/read/28643737/changes-in-pharyngeal-constrictor-volumes-during-head-and-neck-radiation-therapy-implications-for-dose-delivery
#1
Akila Kumarasiri, Chang Liu, Mona Kamal, Correen Fraser, Stephen Brown, Indrin J Chetty, Jinkoo Kim, Farzan Siddiqui
OBJECTIVE: The objective of this study was to evaluate the anatomical changes and associated dosimetric consequences to pharyngeal constrictor muscles (PCMs) that occur during head and neck (H and N) radiotherapy (RT). MATERIALS AND METHODS: A cohort of 13 oropharyngeal cancer patients with daily cone beam computed tomography (CBCT) was retrospectively studied. On every 5th CBCT image, PCM was manually delineated by a radiation oncologist. The anterior-posterior PCM thickness was measured at the midline level of C3 vertebral body...
April 2017: Journal of Cancer Research and Therapeutics
https://www.readbyqxmd.com/read/28638170/atlas-based-automatic-measurements-of-the-morphology-of-the-tibiofemoral-joint
#2
M Brehler, G Thawait, W Shyr, J Ramsay, J H Siewerdsen, W Zbijewski
PURPOSE: Anatomical metrics of the tibiofemoral joint support assessment of joint stability and surgical planning. We propose an automated, atlas-based algorithm to streamline the measurements in 3D images of the joint and reduce user-dependence of the metrics arising from manual identification of the anatomical landmarks. METHODS: The method is initialized with coarse registrations of a set of atlas images to the fixed input image. The initial registrations are then refined separately for the tibia and femur and the best matching atlas is selected...
February 11, 2017: Proceedings of SPIE
https://www.readbyqxmd.com/read/28637483/analyzing-human-decisions-in-igrt-of-head-and-neck-cancer-patients-to-teach-image-registration-algorithms-what-experts-know
#3
Eva Maria Stoiber, Nina Bougatf, Hendrik Teske, Christian Bierstedt, Dieter Oetzel, Jürgen Debus, Rolf Bendl, Kristina Giske
BACKGROUND: In IGRT of deformable head-and-neck anatomy, patient setup corrections are derived by rigid registration methods. In practice, experienced radiation therapists often correct the resulting vectors, thus indicating a different prioritization of alignment of local structures. Purpose of this study is to transfer the knowledge experts apply when correcting the automatically generated result (pre-match) to automated registration. METHODS: Datasets of 25 head-and-neck-cancer patients with daily CBCTs and corresponding approved setup correction vectors were analyzed...
June 21, 2017: Radiation Oncology
https://www.readbyqxmd.com/read/28625473/effect-of-dir-uncertainty-on-prostate-passive-scattering-proton-therapy-dose-accumulation
#4
Yoshitomo Abe, Noriyuki Kadoya, Kazuhiro Arai, Yoshiki Takayama, Takahiro Kato, Kanako Kimura, Takashi Ono, Tatsuya Nakamura, Hitoshi Wada, Yasuhiro Kikuchi, Keiichi Jingu
Deformable image registration (DIR) is important in dose accumulation. Currently, the impact of DIR-algorithm-associated uncertainties in proton therapy is unclear. Here, we quantify the effect of DIR uncertainties on prostate passive-scattering proton therapy (PSPT) dose accumulation. Ten patients with an intermediate risk for prostate cancer formerly treated by PSPT (PTV D95=78GyE) were studied. Dose distributions from all verification CT images (five images per patient) were warped and accumulated in the planning CT geometries with DIR...
June 15, 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28624755/stereo-vision-based-tracking-of-soft-tissue-motion-with-application-to-online-ablation-control-in-laser-microsurgery
#5
Andreas Schoob, Dennis Kundrat, Lüder A Kahrs, Tobias Ortmaier
Recent research has revealed that image-based methods can enhance accuracy and safety in laser microsurgery. In this study, non-rigid tracking using surgical stereo imaging and its application to laser ablation is discussed. A recently developed motion estimation framework based on piecewise affine deformation modeling is extended by a mesh refinement step and considering texture information. This compensates for tracking inaccuracies potentially caused by inconsistent feature matches or drift. To facilitate online application of the method, computational load is reduced by concurrent processing and affine-invariant fusion of tracking and refinement results...
June 8, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28622410/accuracy-of-deformable-image-registration-on-magnetic-resonance-images-in-digital-and-physical-phantoms
#6
Rachel B Ger, Jinzhong Yang, Yao Ding, Megan C Jacobsen, Clifton D Fuller, Rebecca M Howell, Heng Li, R Jason Stafford, Shouhao Zhou, Laurence E Court
PURPOSE: Accurate deformable image registration is necessary for longitudinal studies. The error associated with commercial systems has been evaluated using computed tomography (CT). Several in-house algorithms have been evaluated for use with magnetic resonance imaging (MRI), but there is still relatively little information about MRI deformable image registration. This work presents an evaluation of two deformable image registration systems, one commercial (Velocity) and one in-house (demons-based algorithm), with MRI using two different metrics to quantify the registration error...
June 16, 2017: Medical Physics
https://www.readbyqxmd.com/read/28619289/validation-of-a-method-for-dose-of-the-day-calculation-in-head-neck-tomotherapy-by-using-planning-ct-to-mvct-deformable-image-registration
#7
M Branchini, C Fiorino, I Dell'Oca, M L Belli, L Perna, N Di Muzio, R Calandrino, S Broggi
PURPOSE: The aim of this study was to test the feasibility and dosimetric accuracy of a method that employs planning CT-to-MVCT deformable image registration (DIR) for calculation of the daily dose for head and neck (HN) patients treated with Helical Tomotherapy (HT). METHODS: For each patient, the planning kVCT (CTplan) was deformably registered to the MVCT acquired at the 15th therapy session (MV15) with a B-Spline Free Form algorithm using Mattes mutual information (open-source software 3D Slicer), resulting in a deformed CT (CTdef)...
June 12, 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28595311/evaluation-of-rectum-and-bladder-dose-accumulation-from-external-beam-radiotherapy-and-brachytherapy-for-cervical-cancer-using-two-different-deformable-image-registration-techniques
#8
Noriyuki Kadoya, YuYa Miyasaka, Takaya Yamamoto, Yoshihiro Kuroda, Kengo Ito, Mizuki Chiba, Yujiro Nakajima, Noriyoshi Takahashi, Masaki Kubozono, Rei Umezawa, Suguru Dobashi, Ken Takeda, Keiichi Jingu
We evaluated dose-volume histogram (DVH) parameters based on deformable image registration (DIR) between brachytherapy (BT) and external beam radiotherapy (EBRT) that included a center-shielded (CS) plan. Eleven cervical cancer patients were treated with BT, and their pelvic and CS EBRT were studied. Planning CT images for EBRT and BT (except for the first BT, used as the reference image) were deformed with DIR to reference image. We used two DIR parameter settings: intensity-based and hybrid. Mean Dice similarity coefficients (DSCs) comparing EBRT with the reference for the uterus, rectum and bladder were 0...
June 8, 2017: Journal of Radiation Research
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
#9
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/28587056/tolerance-of-the-brachial-plexus-to-high-dose-reirradiation
#10
Allen M Chen, Taeko Yoshizaki, Maria A Velez, Argin G Mikaeilian, Sophia Hsu, Minsong Cao
PURPOSE: To study the tolerance of the brachial plexus to high doses of radiation exceeding historically accepted limits by analyzing human subjects treated with reirradiation for recurrent tumors of the head and neck. METHODS AND MATERIALS: Data from 43 patients who were confirmed to have received overlapping dose to the brachial plexus after review of radiation treatment plans from the initial and reirradiation courses were used to model the tolerance of this normal tissue structure...
May 1, 2017: International Journal of Radiation Oncology, Biology, Physics
https://www.readbyqxmd.com/read/28573978/automatic-contour-propagation-using-deformable-image-registration-to-determine-delivered-dose-to-spinal-cord-in-head-and-neck-cancer-radiotherapy
#11
Ping Lin Yeap, David Noble, Karl Harrison, Amy Bates, Neil Burnet, Rajesh Jena, Marina Romanchikova, Michael Sutcliffe, Simon Thomas, Gill Barnett, Richard Benson, Sarah Jefferies, M Parker
To determine delivered dose to the spinal cord, a technique has been developed to propagate manual contours from kilovoltage computed-tomography (kVCT) scans for treatment planning to megavoltage computed-tomography (MVCT) guidance scans. The technique uses the Elastix software to perform intensity-based deformable image registration of each kVCT scan to the associated MVCT scans. The registration transform is then applied to contours of the spinal cord drawn manually on the kVCT scan, to obtain contour positions on the MVCT scans...
June 2, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28550405/projective-biomechanical-depth-matching-for-soft-tissue-registration-in-laparoscopic-surgery
#12
Daniel Reichard, Dominik Häntsch, Sebastian Bodenstedt, Stefan Suwelack, Martin Wagner, Hannes Kenngott, Beat Müller-Stich, Lena Maier-Hein, Rüdiger Dillmann, Stefanie Speidel
PURPOSE: A key component of computer- assisted surgery systems is the accurate and robust registration of preoperative planning data with intraoperative sensor data. In laparoscopic surgery, this image-based registration remains challenging due to soft tissue deformations. This paper presents a novel approach for biomechanical soft tissue registration of preoperative CT data with stereo endoscopic image data. METHODS: The proposed method consists of two registrations steps...
May 26, 2017: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/28545068/automatically-tracking-neurons-in-a-moving-and-deforming-brain
#13
Jeffrey P Nguyen, Ashley N Linder, George S Plummer, Joshua W Shaevitz, Andrew M Leifer
Advances in optical neuroimaging techniques now allow neural activity to be recorded with cellular resolution in awake and behaving animals. Brain motion in these recordings pose a unique challenge. The location of individual neurons must be tracked in 3D over time to accurately extract single neuron activity traces. Recordings from small invertebrates like C. elegans are especially challenging because they undergo very large brain motion and deformation during animal movement. Here we present an automated computer vision pipeline to reliably track populations of neurons with single neuron resolution in the brain of a freely moving C...
May 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28543091/intraoperative-localized-constrained-registration-in-navigated-bronchoscopy
#14
Erlend Fagertun Hofstad, Hanne Sorger, Janne Beate Lervik Bakeng, Lucian Gruionu, Håkon Olav Leira, Tore Amundsen, Thomas Langø
PURPOSE: One of the major challenges in electromagnetic navigated bronchoscopy is the navigation accuracy. An initial rigid image-to-patient registration may not be optimal for the entire lung volume, as the lung tissue anatomy is likely to have shifted since the time of computer tomography (CT) acquisition. The accuracy of the initial rigid registration will also be affected throughout the procedure by breathing, coughing, patient movement and tissue displacements due to pressure from bronchoscopy tools...
May 25, 2017: Medical Physics
https://www.readbyqxmd.com/read/28535910/dose-warping-performance-in-deformable-image-registration-in-lung
#15
Shunsuke Moriya, Hidenobu Tachibana, Nozomi Kitamura, Amit Sawant, Masanori Sato
PURPOSE: It is unclear that spatial accuracy can reflect the impact of deformed dose distribution. In this study, we used dosimetric parameters to compare an in-house deformable image registration (DIR) system using NiftyReg, with two commercially available systems, MIM Maestro (MIM) and Velocity AI (Velocity). METHODS: For 19 non-small-cell lung cancer patients, the peak inspiration (0%)-4DCT images were deformed to the peak expiration (50%)-4DCT images using each of the three DIR systems, which included computation of the deformation vector fields (DVF)...
May 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28533050/dual-core-steered-non-rigid-registration-for-multi-modal-images-via-bi-directional-image-synthesis
#16
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/28521203/3d-full-field-quantification-of-cell-induced-large-deformations-in-fibrillar-biomaterials-by-combining-non-rigid-image-registration-with-label-free-second-harmonic-generation
#17
Alvaro Jorge-Peñas, Hannelore Bové, Kathleen Sanen, Marie-Mo Vaeyens, Christian Steuwe, Maarten Roeffaers, Marcel Ameloot, Hans Van Oosterwyck
To advance our current understanding of cell-matrix mechanics and its importance for biomaterials development, advanced three-dimensional (3D) measurement techniques are necessary. Cell-induced deformations of the surrounding matrix are commonly derived from the displacement of embedded fiducial markers, as part of traction force microscopy (TFM) procedures. However, these fluorescent markers may alter the mechanical properties of the matrix or can be taken up by the embedded cells, and therefore influence cellular behavior and fate...
May 10, 2017: Biomaterials
https://www.readbyqxmd.com/read/28520556/breast-tissue-stiffness-estimation-for-surgical-guidance-using-gravity-induced-excitation
#18
Rebekah H Griesenauer, Jared A Weis, Lori R Arlinghaus, Ingrid M Meszoely, Michael I Miga
Tissue stiffness interrogation is fundamental in breast cancer diagnosis and treatment. Furthermore, biomechanical models for predicting breast deformations have been created for several breast cancer applications. Within these applications, constitutive mechanical properties must be defined and the accuracy of this estimation directly impacts the overall performance of the model. In this study, we present an image-derived computational framework to obtain quantitative, patient specific stiffness properties for application in image-guided breast cancer surgery and interventions...
May 18, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28516043/quantification-of-regional-deformation-of-the-lungs-by-non-rigid-registration-of-three-dimensional-contrast-enhanced-magnetic-resonance-imaging
#19
Jiaxin Shao, Peng Hu
BACKGROUND: Assessment of lung function is vital for the diagnosis of a variety of pathological conditions. Research has been proposed to study pulmonary mechanics and kinematics using two-dimensional (2D) magnetic resonance imaging (MRI). This allows estimation of regional lung tissue mechanics but is limited to 2D information. An approach based on three-dimensional (3D) contrast-enhanced MR angiogram of pulmonary blood vessels and a non-rigid image registration technique is proposed for quantification of lung regional deformations, which can potentially be used for assessment of pulmonary parenchymal mechanics and regional ventilation for disease diagnosis without ionizing radiation...
April 2017: Quantitative Imaging in Medicine and Surgery
https://www.readbyqxmd.com/read/28513864/the-influence-of-non-rigid-anatomy-and-patient-positioning-on-endoscopy-ct-image-registration-in-the-head-and-neck
#20
W Scott Ingram, Jinzhong Yang, Richard Wendt, Beth M Beadle, Arvind Rao, Xin A Wang, Laurence E Court
PURPOSE: To assess the influence of non-rigid anatomy and differences in patient positioning between CT acquisition and endoscopic examination on endoscopy-CT image registration in the head and neck. METHODS: Radiotherapy planning CTs and 31-35 daily treatment-room CTs were acquired for nineteen patients. Diagnostic CTs were acquired for thirteen of the patients. The surfaces of the airways were segmented on all scans and triangular meshes were created to render virtual endoscopic images with a calibrated pinhole model of an endoscope...
May 17, 2017: Medical Physics
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