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Deformable Image Registration

Da Li, Yu-Ming Jiao, Liang Wang, Fu-Xin Lin, Jun Wu, Xian-Zeng Tong, Shuo Wang, Yong Cao
OBJECTIVE Surgical management of brainstem lesions is challenging due to the highly compact, eloquent anatomy of the brainstem. This study aimed to evaluate the safety and efficacy of preoperative diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) in brainstem cavernous malformations (CMs). METHODS A prospective randomized controlled clinical trial was performed by using stratified blocked randomization. The primary eligibility criterion of the study was being a surgical candidate for brainstem CMs (with informed consent)...
March 16, 2018: Journal of Neurosurgery
Fantin Girard, Conrad Kavalec, Farida Cheriet
Optic disc (OD) appearance in fundus images is one of the clinical indicators considered in the assessment of retinal diseases such as glaucoma. The cup-to-disc ratio (CDR) is the most common clinical measurement used to characterize glaucoma. However, the CDR only evaluates the relative sizes of the cup and the OD via their diameters. We propose to construct an atlas-based shape descriptor (ASD) to statistically characterize the geometric deformations of the OD shape and of the blood vessels' configuration inside the OD region...
January 2018: Journal of Medical Imaging
Yingxuan Chen, Fang-Fang Yin, Yawei Zhang, You Zhang, Lei Ren
Compressed sensing reconstruction using total variation (TV) tends to over-smooth the edge information by uniformly penalizing the image gradient. The goal of this study is to develop a novel prior contour based TV (PCTV) method to enhance the edge information in compressed sensing reconstruction for CBCT. 
 Methods: The edge information is extracted from prior planning-CT via edge detection. Prior CT is first registered with on-board CBCT reconstructed with TV method through rigid or deformable registration...
March 14, 2018: Physics in Medicine and Biology
Irene Polycarpou, Georgios Soultanidis, Charalampos Tsoumpas
The investigation of the performance of different positron emission tomography (PET) reconstruction and motion compensation methods requires accurate and realistic representation of the anatomy and motion trajectories as observed in real subjects during acquisitions. The generation of well-controlled clinical datasets is difficult due to the many different clinical protocols, scanner specifications, patient sizes, and physiological variations. Alternatively, computational phantoms can be used to generate large data sets for different disease states, providing a ground truth...
March 2018: IEEE Transactions on Medical Imaging
N Chicherova, S E Hieber, A Khimchenko, C Bikis, B Müller, P Cattin
Localizing a histological section in the three-dimensional dataset of a different imaging modality is a challenging 2D-3D registration problem. In the literature, several approaches have been proposed to solve this problem; however, they cannot be considered as fully automatic. Recently, we developed an automatic algorithm that could successfully find the position of a histological section in a micro computed tomography (μCT) volume. For the majority of the datasets, the result of localization corresponded to the manual results...
March 13, 2018: Journal of Microscopy
Menuka Pallebage-Gamarallage, Sean Foxley, Ricarda A L Menke, Istvan N Huszar, Mark Jenkinson, Benjamin C Tendler, Chaoyue Wang, Saad Jbabdi, Martin R Turner, Karla L Miller, Olaf Ansorge
BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a clinically and histopathologically heterogeneous neurodegenerative disorder, in which therapy is hindered by the rapid progression of disease and lack of biomarkers. Magnetic resonance imaging (MRI) has demonstrated its potential for detecting the pathological signature and tracking disease progression in ALS. However, the microstructural and molecular pathological substrate is poorly understood and generally defined histologically...
March 13, 2018: BMC Neuroscience
Jun Lv, Wenjian Huang, Jue Zhang, Xiaoying Wang
OBJECTIVE: In free-breathing multi-b-value diffusion-weighted imaging (DWI), a series of images typically requires several minutes to collect. During respiration the kidney is routinely displaced and may also undergo deformation. These respiratory motion effects generate artifacts and these are the main sources of error in the quantification of intravoxel incoherent motion (IVIM) derived parameters. This work proposes a fully automated framework that combines a kidney segmentation to improve the registration accuracy Methods: Ten healthy subjects were recruited to participate in this experiment...
March 12, 2018: British Journal of Radiology
Xiaokang Yu, Na Lei, Yalin Wang, Xianfeng Gu
3D dynamic surface tracking is an important research problem and plays a vital role in many computer vision and medical imaging applications. However, it is still challenging to efficiently register surface sequences which has large deformations and strong noise. In this paper, we propose a novel automatic method for non-rigid 3D dynamic surface tracking with surface Ricci flow and Teichmüller map methods. According to quasi-conformal Teichmüller theory, the Techmüller map minimizes the maximal dilation so that our method is able to automatically register surfaces with large deformations...
October 2017: Proceedings
Vikas Gupta, Yibing Wang, Alejandra Méndez Romero, Andriy Myronenko, Petr Jordan, Calvin Maurer, Ben Heijmen, Mischa Hoogeman
PURPOSE: To validate a novel deformable image registration (DIR) method for online adaptation of planning organ-at-risk (OAR) delineations to match daily anatomy during hypo-fractionated RT of abdominal tumors. MATERIALS AND METHODS: For 20 liver cancer patients, planning OAR delineations were adapted to daily anatomy using the DIR on corresponding repeat CTs. The DIR's accuracy was evaluated for the entire cohort by comparing adapted and expert-drawn OAR delineations using geometric (Dice Similarity Coefficient (DSC), Modified Hausdorff Distance (MHD) and Mean Surface Error (MSE)) and dosimetric (Dmax and Dmean ) measures...
March 8, 2018: Radiotherapy and Oncology: Journal of the European Society for Therapeutic Radiology and Oncology
Tomoharu Mochizuki, Takashi Sato, Osamu Tanifuji, Satoshi Watanabe, Koichi Kobayashi, Naoto Endo
BACKGROUND: This study aimed to identify the factors affecting postoperative rotational limb alignment of the tibia relative to the femur. We hypothesized that not only component positions but also several intrinsic factors were associated with postoperative rotational limb alignment. METHODS: This study included 99 knees (90 women and 9 men) with a mean age of 77 ± 6 years. A three-dimensional (3D) assessment system was applied under weight-bearing conditions to biplanar long-leg radiographs using 3D-to-2D image registration technique...
February 13, 2018: Journal of Arthroplasty
Yujia Zhou, Han Zhang, Lichi Zhang, Xiaohuan Cao, Ru Yang, Qianjin Feng, Pew-Thian Yap, Dinggang Shen
Population studies of brain function with resting-state functional magnetic resonance imaging (rs-fMRI) rely on accurate intersubject registration of functional areas. This is typically achieved through registration using high-resolution structural images with more spatial details and better tissue contrast. However, accumulating evidence has suggested that such strategy cannot align functional regions well because functional areas are not necessarily consistent with anatomical structures. To alleviate this problem, a number of registration algorithms based directly on rs-fMRI data have been developed, most of which utilize functional connectivity (FC) features for registration...
March 5, 2018: Human Brain Mapping
Elvis Dohmatob, Gael Varoquaux, Bertrand Thirion
In Echo-Planar Imaging (EPI)-based Magnetic Resonance Imaging (MRI), inter-subject registration typically uses the subject's T1-weighted (T1w) anatomical image to learn deformations of the subject's brain onto a template. The estimated deformation fields are then applied to the subject's EPI scans (functional or diffusion-weighted images) to warp the latter to a template space. Historically, such indirect T1w-based registration was motivated by the lack of clear anatomical details in low-resolution EPI images: a direct registration of the EPI scans to template space would be futile...
2018: Frontiers in Neuroscience
Hoda Sharifi, Hong Zhang, Hassan Bagher Ebadian, Wei Lu, Munther I Ajlouni, Jian-Yue Jin, Feng-Ming Spring Kong, Indrin J Chetty, Hualiang Zhong
Tumor response to radiation treatment (RT) can be evaluated from changes in metabolic activity between two positron emission tomography (PET) images. Activity changes at individual voxels in pre-treatment PET images (PET1), however, cannot be derived until their associated PET-CT (CT1) images are appropriately registered to during-treatment PET-CT (CT2) images. This study aimed to investigate the feasibility of using deformable image registration (DIR) techniques to quantify radiation-induced metabolic changes on PET images...
February 26, 2018: Physics in Medicine and Biology
Michael MacFarlane, Daniel Wong, Douglas A Hoover, Eugene Wong, Carol Johnson, Jerry J Battista, Jeff Z Chen
PURPOSE: In this work, we propose a new method of calibrating cone beam computed tomography (CBCT) data sets for radiotherapy dose calculation and plan assessment. The motivation for this patient-specific calibration (PSC) method is to develop an efficient, robust, and accurate CBCT calibration process that is less susceptible to deformable image registration (DIR) errors. METHODS: Instead of mapping the CT numbers voxel-by-voxel with traditional DIR calibration methods, the PSC methods generates correlation plots between deformably registered planning CT and CBCT voxel values, for each image slice...
February 26, 2018: Journal of Applied Clinical Medical Physics
Kyle R Padgett, Radka Stoyanova, Sara Pirozzi, Perry Johnson, Jon Piper, Nesrin Dogan, Alan Pollack
PURPOSE: Validating deformable multimodality image registrations is challenging due to intrinsic differences in signal characteristics and their spatial intensity distributions. Evaluating multimodality registrations using these spatial intensity distributions is also complicated by the fact that these metrics are often employed in the registration optimization process. This work evaluates rigid and deformable image registrations of the prostate in between diagnostic-MRI and radiation treatment planning-CT by utilizing a planning-MRI after fiducial marker placement as a surrogate...
February 23, 2018: Journal of Applied Clinical Medical Physics
Roberto Berenguer, Victoria de la Vara, Veronica Lopez-Honrubia, Ana Teresa Nuñez, Miguel Rivera, Maria Victoria Villas, Sebastia Sabater
PURPOSE: To analyse the influence of the image registration method on the adaptive radiotherapy of an IMRT prostate treatment, and to compare the dose accumulation according to 3 different image registration methods with the planned dose. MATERIAL AND METHODS: The IMRT prostate patient was CT imaged 3 times throughout his treatment. The prostate, PTV, rectum and bladder were segmented on each CT. A Rigid, a deformable (DIR) B-spline and a DIR with landmarks registration algorithms were employed...
January 2018: Physica Medica: PM
Elisa Grassi, Federica Fioroni, Salvatore Berenato, Nick Patterson, Valentina Ferri, Luca Braglia, Angelina Filice, Annibale Versari, Mauro Iori, Emiliano Spezi
Peptide receptor radionuclide therapy (PRRT) is an effective MRT (molecular radiotherapy) treatment, which consists of multiple administrations of a radiopharmaceutical labelled with177 Lu or90 Y. Through sequential functional imaging a patient specific 3D dosimetry can be derived. Multiple scans should be previously co-registered to allow accurate absorbed dose calculations. The purpose of this study is to evaluate the impact of image registration algorithms on 3D absorbed dose calculation. A cohort of patients was extracted from the database of a clinical trial in PRRT...
January 2018: Physica Medica: PM
Dante P I Capaldi, Rachel L Eddy, Sarah Svenningsen, Fumin Guo, John S H Baxter, A Jonathan McLeod, Parameswaran Nair, David G McCormack, Grace Parraga
Purpose To measure regional specific ventilation with free-breathing hydrogen 1 (1 H) magnetic resonance (MR) imaging without exogenous contrast material and to investigate correlations with hyperpolarized helium 3 (3 He) MR imaging and pulmonary function test measurements in healthy volunteers and patients with asthma. Materials and Methods Subjects underwent free-breathing1 H and static breath-hold hyperpolarized3 He MR imaging as well as spirometry and plethysmography; participants were consecutively recruited between January and June 2017...
February 22, 2018: Radiology
Tom Edward Marchant, Kiran Daniel Joshi, Christopher J Moore
Radiotherapy dose calculations based on cone-beam CT (CBCT) images can be inaccurate due to unreliable Hounsfield units (HU) in the CBCT. Deformable image registration of planning CT images to CBCT, and direct correction of CBCT image values are two methods proposed to allow heterogeneity corrected dose calculations based on CBCT. In this paper we compare the accuracy and robustness of these two approaches. CBCT images for 44 patients were used including pelvis, lung and head & neck sites. CBCT HU were corrected using a "shading correction" algorithm and via deformable registration of planning CT to CBCT using either Elastix or Niftyreg...
February 20, 2018: Physics in Medicine and Biology
Bastien Rigaud, Antoine Simon, Maxime Gobeli, Caroline Lafond, Julie Leseur, Anais Barateau, Nicolas Jaksic, Joël Castelli, Danièle Williaume, Pascal Haigron, Renaud De Crevoisier
PURPOSE: In the context of adaptive radiation therapy (ART) for locally advanced cervical carcinoma (LACC), this study proposed an original cone-beam computed tomography (CBCT)-guided "Evolutive library" and evaluated it against four other known radiotherapy (RT) strategies. MATERIAL AND METHODS: For 20 patients who underwent intensity-modulated radiation therapy (IMRT) for LACC, three planning CTs (with empty [EB], intermediate [IB], and full [FB] bladder volumes), a CT scan at 20 Gy and bi-weekly CBCTs for 5 weeks were performed...
February 17, 2018: Medical Physics
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