WorldWideScience

Sample records for 3d ct images

  1. Optical-CT imaging of complex 3D dose distributions

    Science.gov (United States)

    Oldham, Mark; Kim, Leonard; Hugo, Geoffrey

    2005-04-01

    The limitations of conventional dosimeters restrict the comprehensiveness of verification that can be performed for advanced radiation treatments presenting an immediate and substantial problem for clinics attempting to implement these techniques. In essence, the rapid advances in the technology of radiation delivery have not been paralleled by corresponding advances in the ability to verify these treatments. Optical-CT gel-dosimetry is a relatively new technique with potential to address this imbalance by providing high resolution 3D dose maps in polymer and radiochromic gel dosimeters. We have constructed a 1st generation optical-CT scanner capable of high resolution 3D dosimetry and applied it to a number of simple and increasingly complex dose distributions including intensity-modulated-radiation-therapy (IMRT). Prior to application to IMRT, the robustness of optical-CT gel dosimetry was investigated on geometry and variable attenuation phantoms. Physical techniques and image processing methods were developed to minimize deleterious effects of refraction, reflection, and scattered laser light. Here we present results of investigations into achieving accurate high-resolution 3D dosimetry with optical-CT, and show clinical examples of 3D IMRT dosimetry verification. In conclusion, optical-CT gel dosimetry can provide high resolution 3D dose maps that greatly facilitate comprehensive verification of complex 3D radiation treatments. Good agreement was observed at high dose levels (>50%) between planned and measured dose distributions. Some systematic discrepancies were observed however (rms discrepancy 3% at high dose levels) indicating further work is required to eliminate confounding factors presently compromising the accuracy of optical-CT 3D gel-dosimetry.

  2. MUTUAL INFORMATION BASED 3D NON-RIGID REGISTRATION OF CT/MR ABDOMEN IMAGES

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A mutual information based 3D non-rigid registration approach was proposed for the registration of deformable CT/MR body abdomen images. The Parzen Windows Density Estimation (PWDE) method is adopted to calculate the mutual information between the two modals of CT and MRI abdomen images. By maximizing MI between the CT and MR volume images, the overlapping part of them reaches the biggest, which means that the two body images of CT and MR matches best to each other. Visible Human Project (VHP) Male abdomen CT and MRI Data are used as experimental data sets. The experimental results indicate that this approach of non-rigid 3D registration of CT/MR body abdominal images can be achieved effectively and automatically, without any prior processing procedures such as segmentation and feature extraction, but has a main drawback of very long computation time. Key words: medical image registration; multi-modality; mutual information; non-rigid; Parzen window density estimation

  3. In vivo 3D PIXE-micron-CT imaging of Drosophila melanogaster using a contrast agent

    Science.gov (United States)

    Matsuyama, Shigeo; Hamada, Naoki; Ishii, Keizo; Nozawa, Yuichiro; Ohkura, Satoru; Terakawa, Atsuki; Hatori, Yoshinobu; Fujiki, Kota; Fujiwara, Mitsuhiro; Toyama, Sho

    2015-04-01

    In this study, we developed a three-dimensional (3D) computed tomography (CT) in vivo imaging system for imaging small insects with micrometer resolution. The 3D CT imaging system, referred to as 3D PIXE-micron-CT (PIXEμCT), uses characteristic X-rays produced by ion microbeam bombardment of a metal target. PIXEμCT was used to observe the body organs and internal structure of a living Drosophila melanogaster. Although the organs of the thorax were clearly imaged, the digestive organs in the abdominal cavity could not be clearly discerned initially, with the exception of the rectum and the Malpighian tubule. To enhance the abdominal images, a barium sulfate powder radiocontrast agent was added. For the first time, 3D images of the ventriculus of a living D. melanogaster were obtained. Our results showed that PIXEμCT can provide in vivo 3D-CT images that reflect correctly the structure of individual living organs, which is expected to be very useful in biological research.

  4. 3D Prior Image Constrained Projection Completion for X-ray CT Metal Artifact Reduction

    NARCIS (Netherlands)

    Mehranian, Abolfazl; Ay, Mohammad Reza; Rahmim, Arman; Zaidi, Habib

    2013-01-01

    The presence of metallic implants in the body of patients undergoing X-ray computed tomography (CT) examinations often results insevere streaking artifacts that degrade image quality. In this work, we propose a new metal artifact reduction (MAR) algorithm for 2D fan-beam and 3D cone-beam CT based on

  5. 3-D MRI/CT fusion imaging of the lumbar spine

    Energy Technology Data Exchange (ETDEWEB)

    Yamanaka, Yuki; Kamogawa, Junji; Misaki, Hiroshi; Kamada, Kazuo; Okuda, Shunsuke; Morino, Tadao; Ogata, Tadanori; Yamamoto, Haruyasu [Ehime University, Department of Bone and Joint Surgery, Toon-shi, Ehime (Japan); Katagi, Ryosuke; Kodama, Kazuaki [Katagi Neurological Surgery, Imabari-shi, Ehime (Japan)

    2010-03-15

    The objective was to demonstrate the feasibility of MRI/CT fusion in demonstrating lumbar nerve root compromise. We combined 3-dimensional (3-D) computed tomography (CT) imaging of bone with 3-D magnetic resonance imaging (MRI) of neural architecture (cauda equina and nerve roots) for two patients using VirtualPlace software. Although the pathological condition of nerve roots could not be assessed using MRI, myelography or CT myelography, 3-D MRI/CT fusion imaging enabled unambiguous, 3-D confirmation of the pathological state and courses of nerve roots, both inside and outside the foraminal arch, as well as thickening of the ligamentum flavum and the locations, forms and numbers of dorsal root ganglia. Positional relationships between intervertebral discs or bony spurs and nerve roots could also be depicted. Use of 3-D MRI/CT fusion imaging for the lumbar vertebral region successfully revealed the relationship between bone construction (bones, intervertebral joints, and intervertebral disks) and neural architecture (cauda equina and nerve roots) on a single film, three-dimensionally and in color. Such images may be useful in elucidating complex neurological conditions such as degenerative lumbar scoliosis(DLS), as well as in diagnosis and the planning of minimally invasive surgery. (orig.)

  6. Intrathoracic tumour motion estimation from CT imaging using the 3D optical flow method

    Science.gov (United States)

    Guerrero, Thomas; Zhang, Geoffrey; Huang, Tzung-Chi; Lin, Kang-Ping

    2004-09-01

    The purpose of this work was to develop and validate an automated method for intrathoracic tumour motion estimation from breath-hold computed tomography (BH CT) imaging using the three-dimensional optical flow method (3D OFM). A modified 3D OFM algorithm provided 3D displacement vectors for each voxel which were used to map tumour voxels on expiration BH CT onto inspiration BH CT images. A thoracic phantom and simulated expiration/inspiration BH CT pairs were used for validation. The 3D OFM was applied to the measured inspiration and expiration BH CT images from one lung cancer and one oesophageal cancer patient. The resulting displacements were plotted in histogram format and analysed to provide insight regarding the tumour motion. The phantom tumour displacement was measured as 1.20 and 2.40 cm with full-width at tenth maximum (FWTM) for the distribution of displacement estimates of 0.008 and 0.006 cm, respectively. The maximum error of any single voxel's motion estimate was 1.1 mm along the z-dimension or approximately one-third of the z-dimension voxel size. The simulated BH CT pairs revealed an rms error of less than 0.25 mm. The displacement of the oesophageal tumours was nonuniform and up to 1.4 cm, this was a new finding. A lung tumour maximum displacement of 2.4 cm was found in the case evaluated. In conclusion, 3D OFM provided an accurate estimation of intrathoracic tumour motion, with estimated errors less than the voxel dimension in a simulated motion phantom study. Surprisingly, oesophageal tumour motion was large and nonuniform, with greatest motion occurring at the gastro-oesophageal junction. Presented at The IASTED Second International Conference on Biomedical Engineering (BioMED 2004), Innsbruck, Austria, 16-18 February 2004.

  7. Parametric modelling and segmentation of vertebral bodies in 3D CT and MR spine images

    Science.gov (United States)

    Štern, Darko; Likar, Boštjan; Pernuš, Franjo; Vrtovec, Tomaž

    2011-12-01

    Accurate and objective evaluation of vertebral deformations is of significant importance in clinical diagnostics and therapy of pathological conditions affecting the spine. Although modern clinical practice is focused on three-dimensional (3D) computed tomography (CT) and magnetic resonance (MR) imaging techniques, the established methods for evaluation of vertebral deformations are limited to measuring deformations in two-dimensional (2D) x-ray images. In this paper, we propose a method for quantitative description of vertebral body deformations by efficient modelling and segmentation of vertebral bodies in 3D. The deformations are evaluated from the parameters of a 3D superquadric model, which is initialized as an elliptical cylinder and then gradually deformed by introducing transformations that yield a more detailed representation of the vertebral body shape. After modelling the vertebral body shape with 25 clinically meaningful parameters and the vertebral body pose with six rigid body parameters, the 3D model is aligned to the observed vertebral body in the 3D image. The performance of the method was evaluated on 75 vertebrae from CT and 75 vertebrae from T2-weighted MR spine images, extracted from the thoracolumbar part of normal and pathological spines. The results show that the proposed method can be used for 3D segmentation of vertebral bodies in CT and MR images, as the proposed 3D model is able to describe both normal and pathological vertebral body deformations. The method may therefore be used for initialization of whole vertebra segmentation or for quantitative measurement of vertebral body deformations.

  8. Effects of CT image segmentation methods on the accuracy of long bone 3D reconstructions.

    Science.gov (United States)

    Rathnayaka, Kanchana; Sahama, Tony; Schuetz, Michael A; Schmutz, Beat

    2011-03-01

    An accurate and accessible image segmentation method is in high demand for generating 3D bone models from CT scan data, as such models are required in many areas of medical research. Even though numerous sophisticated segmentation methods have been published over the years, most of them are not readily available to the general research community. Therefore, this study aimed to quantify the accuracy of three popular image segmentation methods, two implementations of intensity thresholding and Canny edge detection, for generating 3D models of long bones. In order to reduce user dependent errors associated with visually selecting a threshold value, we present a new approach of selecting an appropriate threshold value based on the Canny filter. A mechanical contact scanner in conjunction with a microCT scanner was utilised to generate the reference models for validating the 3D bone models generated from CT data of five intact ovine hind limbs. When the overall accuracy of the bone model is considered, the three investigated segmentation methods generated comparable results with mean errors in the range of 0.18-0.24 mm. However, for the bone diaphysis, Canny edge detection and Canny filter based thresholding generated 3D models with a significantly higher accuracy compared to those generated through visually selected thresholds. This study demonstrates that 3D models with sub-voxel accuracy can be generated utilising relatively simple segmentation methods that are available to the general research community.

  9. Evaluating 3D registration of CT-scan images using crest lines

    Science.gov (United States)

    Ayache, Nicholas; Gueziec, Andre P.; Thirion, Jean-Philippe; Gourdon, A.; Knoplioch, Jerome

    1993-06-01

    We consider the issue of matching 3D objects extracted from medical images. We show that crest lines computed on the object surfaces correspond to meaningful anatomical features, and that they are stable with respect to rigid transformations. We present the current chain of algorithmic modules which automatically extract the major crest lines in 3D CT-Scan images, and then use differential invariants on these lines to register together the 3D images with a high precision. The extraction of the crest lines is done by computing up to third order derivatives of the image intensity function with appropriate 3D filtering of the volumetric images, and by the 'marching lines' algorithm. The recovered lines are then approximated by splines curves, to compute at each point a number of differential invariants. Matching is finally performed by a new geometric hashing method. The whole chain is now completely automatic, and provides extremely robust and accurate results, even in the presence of severe occlusions. In this paper, we briefly describe the whole chain of processes, already presented to evaluate the accuracy of the approach on a couple of CT-scan images of a skull containing external markers.

  10. Computer-aided diagnosis for osteoporosis using chest 3D CT images

    Science.gov (United States)

    Yoneda, K.; Matsuhiro, M.; Suzuki, H.; Kawata, Y.; Niki, N.; Nakano, Y.; Ohmatsu, H.; Kusumoto, M.; Tsuchida, T.; Eguchi, K.; Kaneko, M.

    2016-03-01

    The patients of osteoporosis comprised of about 13 million people in Japan and it is one of the problems the aging society has. In order to prevent the osteoporosis, it is necessary to do early detection and treatment. Multi-slice CT technology has been improving the three dimensional (3-D) image analysis with higher body axis resolution and shorter scan time. The 3-D image analysis using multi-slice CT images of thoracic vertebra can be used as a support to diagnose osteoporosis and at the same time can be used for lung cancer diagnosis which may lead to early detection. We develop automatic extraction and partitioning algorithm for spinal column by analyzing vertebral body structure, and the analysis algorithm of the vertebral body using shape analysis and a bone density measurement for the diagnosis of osteoporosis. Osteoporosis diagnosis support system obtained high extraction rate of the thoracic vertebral in both normal and low doses.

  11. Quantification and visualization of alveolar bone resorption from 3D dental CT images

    Energy Technology Data Exchange (ETDEWEB)

    Nagao, Jiro; Mori, Kensaku; Kitasaka, Takayuki; Suenaga, Yasuhito [Nagoya University, Graduate School of Information Science, Nagoya (Japan); Yamada, Shohzoh; Naitoh, Munetaka [Aichi-Gakuin University, School of Dentistry, Nagoya (Japan)

    2007-06-15

    Purpose A computer aided diagnosis (CAD) system for quantifying and visualizing alveolar bone resorption caused by periodontitis was developed based on three-dimensional (3D) image processing of dental CT images. Methods The proposed system enables visualization and quantification of resorption of alveolar bone surrounding and between the roots of teeth. It has the following functions: (1) vertical measurement of the depth of resorption surrounding the tooth in 3D images, avoiding physical obstruction; (2) quantification of the amount of resorption in the furcation area; and (3) visualization of quantification results by pseudo-color maps, graphs, and motion pictures. The resorption measurement accuracy in the area surrounding teeth was evaluated by comparing with dentist's recognition on five real patient CT images, giving average absolute difference of 0.87 mm. An artificial image with mathematical truth was also used for measurement evaluation. Results The average absolute difference was 0.36 and 0.10 mm for surrounding and furcation areas, respectively. The system provides an intuitive presentation of the measurement results. Conclusion Computer aided diagnosis of 3D dental CT scans is feasible and the technique is a promising new tool for the quantitative evaluation of periodontal bone loss. (orig.)

  12. SU-E-J-209: Verification of 3D Surface Registration Between Stereograms and CT Images

    Energy Technology Data Exchange (ETDEWEB)

    Han, T; Gifford, K [UT MD Anderson Cancer Center, Houston, TX (United States); Smith, B [MD Anderson Cancer Center, Houston, TX (United States); Salehpour, M [M.D. Anderson Cancer Center, Houston, TX (United States)

    2014-06-01

    Purpose: Stereography can provide a visualization of the skin surface for radiation therapy patients. The aim of this study was to verify the registration algorithm in a commercial image analysis software, 3dMDVultus, for the fusion of stereograms and CT images. Methods: CT and stereographic scans were acquired of a head phantom and a deformable phantom. CT images were imported in 3dMDVultus and the surface contours were generated by threshold segmentation. Stereograms were reconstructed in 3dMDVultus. The resulting surfaces were registered with Vultus algorithm and then exported to in-house registration software and compared with four algorithms: rigid, affine, non-rigid iterative closest point (ICP) and b-spline algorithm. RMS (root-mean-square residuals of the surface point distances) error between the registered CT and stereogram surfaces was calculated and analyzed. Results: For the head phantom, the maximum RMS error between registered CT surfaces to stereogram was 6.6 mm for Vultus algorithm, whereas the mean RMS error was 0.7 mm. For the deformable phantom, the maximum RMS error was 16.2 mm for Vultus algorithm, whereas the mean RMS error was 4.4 mm. Non-rigid ICP demonstrated the best registration accuracy, as the mean of RMS errors were both within 1 mm. Conclusion: The accuracy of registration algorithm in 3dMDVultus was verified and exceeded RMS of 2 mm for deformable cases. Non-rigid ICP and b-spline algorithms improve the registration accuracy for both phantoms, especially in deformable one. For those patients whose body habitus deforms during radiation therapy, more advanced nonrigid algorithms need to be used.

  13. Improving Low-dose Cardiac CT Images based on 3D Sparse Representation

    Science.gov (United States)

    Shi, Luyao; Hu, Yining; Chen, Yang; Yin, Xindao; Shu, Huazhong; Luo, Limin; Coatrieux, Jean-Louis

    2016-03-01

    Cardiac computed tomography (CCT) is a reliable and accurate tool for diagnosis of coronary artery diseases and is also frequently used in surgery guidance. Low-dose scans should be considered in order to alleviate the harm to patients caused by X-ray radiation. However, low dose CT (LDCT) images tend to be degraded by quantum noise and streak artifacts. In order to improve the cardiac LDCT image quality, a 3D sparse representation-based processing (3D SR) is proposed by exploiting the sparsity and regularity of 3D anatomical features in CCT. The proposed method was evaluated by a clinical study of 14 patients. The performance of the proposed method was compared to the 2D spares representation-based processing (2D SR) and the state-of-the-art noise reduction algorithm BM4D. The visual assessment, quantitative assessment and qualitative assessment results show that the proposed approach can lead to effective noise/artifact suppression and detail preservation. Compared to the other two tested methods, 3D SR method can obtain results with image quality most close to the reference standard dose CT (SDCT) images.

  14. Automatic Detection and Segmentation of Kidneys in 3D CT Images Using Random Forests

    OpenAIRE

    Cuingnet, Rémi; Prevost, Raphaël; Lesage, David; Cohen, Laurent D.; Mory, Benoît; Ardon, Roberto

    2012-01-01

    International audience; Kidney segmentation in 3D CT images allows extracting useful information for nephrologists. For practical use in clinical routine, such an algorithm should be fast, automatic and robust to contrast-agent enhancement and elds of view. By combining and re ning state-of-the-art techniques (random forests and template deformation), we demonstrate the possibility of building an algorithm that meets these requirements. Kidneys are localized with random forests following a co...

  15. 3D imaging with an isocentric mobile C-arm comparison of image quality with spiral CT.

    Science.gov (United States)

    Kotsianos, Dorothea; Wirth, Stefan; Fischer, Tanja; Euler, Ekkehard; Rock, Clemens; Linsenmaier, Ulrich; Pfeifer, Klaus Jürgen; Reiser, Maximilian

    2004-09-01

    The purpose of this study was to evaluate the image quality of the new 3D imaging system (ISO-C-3D) for osteosyntheses of tibial condylar fractures in comparison with spiral CT (CT). Sixteen human cadaveric knees were examined with a C-arm 3D imaging system and spiral computed tomography. Various screws and plates of steel and titanium were used for osteosynthesis in these specimens. Image quality and clinical value of multiplanar (MP) reformatting of both methods were analyzed. In addition, five patients with tibial condylar fractures were examined for diagnosis and intra-operative control. The image quality of the C-arm 3D imaging system in the cadaveric study was rated as significantly worse than that of spiral CT with and without prostheses. After implantation of prostheses an increased incidence of artifacts was observed, but the diagnostic accuracy was not affected. Titanium implants caused the smallest number of artifacts. The image quality of ISO-C is inferior to CT, and metal artifacts were more prominent, but the clinical value was equal. ISO-C-3D can be useful in planning operative reconstructions and can verify the reconstruction of articular surfaces and the position of implants with diagnostic image quality.

  16. 3D imaging with an isocentric mobile C-arm. Comparison of image quality with spiral CT

    Energy Technology Data Exchange (ETDEWEB)

    Kotsianos, Dorothea; Wirth, Stefan; Fischer, Tanja; Euler, Ekkehard; Rock, Clemens; Linsenmaier, Ulrich; Pfeifer, Klaus Juergen; Reiser, Maximilian [Departments of Radiology and Surgery, Klinikum der Universitaet Muenchen, Innenstadt, Nussbaumstrasse 20, 80336, Munchen (Germany)

    2004-09-01

    The purpose of this study was to evaluate the image quality of the new 3D imaging system (ISO-C-3D) for osteosyntheses of tibial condylar fractures in comparison with spiral CT (CT). Sixteen human cadaveric knees were examined with a C-arm 3D imaging system and spiral computed tomography. Various screws and plates of steel and titanium were used for osteosynthesis in these specimens. Image quality and clinical value of multiplanar (MP) reformatting of both methods were analyzed. In addition, five patients with tibial condylar fractures were examined for diagnosis and intra-operative control. The image quality of the C-arm 3D imaging system in the cadaveric study was rated as significantly worse than that of spiral CT with and without prostheses. After implantation of prostheses an increased incidence of artifacts was observed, but the diagnostic accuracy was not affected. Titanium implants caused the smallest number of artifacts. The image quality of ISO-C is inferior to CT, and metal artifacts were more prominent, but the clinical value was equal. ISO-C-3D can be useful in planning operative reconstructions and can verify the reconstruction of articular surfaces and the position of implants with diagnostic image quality. (orig.)

  17. Application of spiral CT image 3D reconstruction in severe talar neck fracture

    Institute of Scientific and Technical Information of China (English)

    HE Fei; HUANG He; DENG Ya-min; Wang Bing; ZHANG Chun-qiang; ZHAO Zhi; TANG Xi-zhang; ZHOU Zhao-wen; ZHAO Xue-ling

    2007-01-01

    Objective:To explore the application of the spiral computerized tomography (CT) image three-dimensional(3D ) reconstruction technique associated with the conventional radiography in the diagnosis and treatment of severe talar neck fracture. Methods:Using the multi-slice spiral CT image 3D reconstruction technique,we analysed 11 cases of talar neck fracture.The fractures were reduced and fixed through a minimal incision and internal fixation with titanium cannulated lag screws. Results:In the 11 cases,the results of CT image 3D reconstruction were in concordance with plain radiograph in 6 case of Hawkins type H.And the remaining 5 cases of Hawkins types Ⅲ and Ⅳ could not be classified exactly only by radiographs,one of whom was misdiagnosed.After using the CT image 3D reconstruction,the 5 cases were classified exactly before osteosynthesis.The classifications of these 11 cases were confirmed finally by surgical findings.The duration of operation were 45-140 min,averaging 81min (including the duration of C-arm fluoroscopy).X-ray exposure time was 6-58 seconds,averaging 22 seconds.The blood loss was less than 100 ml.The fracture union was achieved in 3 months. No nonunion, talus avascular necrosis or joint surface collapse occurred.Postoperative follow-up was from 1 to 25 months.According to Hawkins score,excellent result was found in 6 type Ⅱ cases and 1type Ⅲ case;good result in 1 type Ⅲ case with both medial and lateral malleolar fracture,1 type Ⅲ with medial malleolus fractures and 1 open type Ⅲ;fair result in 1 open type Ⅳ with lateral malleolus fracture. Conclusions:By using the multi-slice spiral CT image 3D reconstruction associated with radiography to diagnose and treat severe talar neck fractures,the accuracy of diagnosis can be improved obviously. Based on this technique,more consummate operational plan can be designed and performed so as to achieve a better therapeutic effect.

  18. 3D visualization of biomedical CT images based on OpenGL and VRML techniques

    Science.gov (United States)

    Yin, Meng; Luo, Qingming; Xia, Fuhua

    2002-04-01

    Current high-performance computers and advanced image processing capabilities have made the application of three- dimensional visualization objects in biomedical computer tomographic (CT) images facilitate the researches on biomedical engineering greatly. Trying to cooperate with the update technology using Internet, where 3D data are typically stored and processed on powerful servers accessible by using TCP/IP, we should hold the results of the isosurface be applied in medical visualization generally. Furthermore, this project is a future part of PACS system our lab is working on. So in this system we use the 3D file format VRML2.0, which is used through the Web interface for manipulating 3D models. In this program we implemented to generate and modify triangular isosurface meshes by marching cubes algorithm. Then we used OpenGL and MFC techniques to render the isosurface and manipulating voxel data. This software is more adequate visualization of volumetric data. The drawbacks are that 3D image processing on personal computers is rather slow and the set of tools for 3D visualization is limited. However, these limitations have not affected the applicability of this platform for all the tasks needed in elementary experiments in laboratory or data preprocessed.

  19. GPU-Based 3D Cone-Beam CT Image Reconstruction for Large Data Volume

    Directory of Open Access Journals (Sweden)

    Xing Zhao

    2009-01-01

    Full Text Available Currently, 3D cone-beam CT image reconstruction speed is still a severe limitation for clinical application. The computational power of modern graphics processing units (GPUs has been harnessed to provide impressive acceleration of 3D volume image reconstruction. For extra large data volume exceeding the physical graphic memory of GPU, a straightforward compromise is to divide data volume into blocks. Different from the conventional Octree partition method, a new partition scheme is proposed in this paper. This method divides both projection data and reconstructed image volume into subsets according to geometric symmetries in circular cone-beam projection layout, and a fast reconstruction for large data volume can be implemented by packing the subsets of projection data into the RGBA channels of GPU, performing the reconstruction chunk by chunk and combining the individual results in the end. The method is evaluated by reconstructing 3D images from computer-simulation data and real micro-CT data. Our results indicate that the GPU implementation can maintain original precision and speed up the reconstruction process by 110–120 times for circular cone-beam scan, as compared to traditional CPU implementation.

  20. 3D spiral CT imaging of bone anomalies in a case of diastematomyelia

    Energy Technology Data Exchange (ETDEWEB)

    Skalej, Martin [Department of Neuroradiology, University of Tuebingen, Hoppe-Seyler Str. 3, 72076 Tuebingen (Germany); Duffner, Frank [Department of Neurosurgery, University of Tuebingen, Tuebingen (Germany); Stefanou, Alexander [Department of Neuroradiology, University of Tuebingen, Hoppe-Seyler Str. 3, 72076 Tuebingen (Germany); Petersen, Dirk [Department of Neuroradiology, University of Tuebingen, Hoppe-Seyler Str. 3, 72076 Tuebingen (Germany)

    1999-03-01

    The case of a 48-year-old woman, suffering from a diastematomyelia, is presented. This case and the diagnostic findings are used to demonstrate the demands on imaging methods with respect to a new classification of split cord malformations (SCMs) recently published. Although MRI is the method of choice for imaging of the spinal cord generally, only X-ray methods and especially conventional computer tomography provide the information necessary for correct classification of SCMs. Additional 3D-reconstructions from suitable CT-data are helpful in visualizing complex anomalies of bony structures found in most cases of SCM.

  1. Integration of 3D anatomical data obtained by CT imaging and 3D optical scanning for computer aided implant surgery

    Directory of Open Access Journals (Sweden)

    Paoli Alessandro

    2011-02-01

    Full Text Available Abstract Background A precise placement of dental implants is a crucial step to optimize both prosthetic aspects and functional constraints. In this context, the use of virtual guiding systems has been recognized as a fundamental tool to control the ideal implant position. In particular, complex periodontal surgeries can be performed using preoperative planning based on CT data. The critical point of the procedure relies on the lack of accuracy in transferring CT planning information to surgical field through custom-made stereo-lithographic surgical guides. Methods In this work, a novel methodology is proposed for monitoring loss of accuracy in transferring CT dental information into periodontal surgical field. The methodology is based on integrating 3D data of anatomical (impression and cast and preoperative (radiographic template models, obtained by both CT and optical scanning processes. Results A clinical case, relative to a fully edentulous jaw patient, has been used as test case to assess the accuracy of the various steps concurring in manufacturing surgical guides. In particular, a surgical guide has been designed to place implants in the bone structure of the patient. The analysis of the results has allowed the clinician to monitor all the errors, which have been occurring step by step manufacturing the physical templates. Conclusions The use of an optical scanner, which has a higher resolution and accuracy than CT scanning, has demonstrated to be a valid support to control the precision of the various physical models adopted and to point out possible error sources. A case study regarding a fully edentulous patient has confirmed the feasibility of the proposed methodology.

  2. 3D iterative helical targeted CT. Application to contrast-enhanced vascular imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gendron, David; Goussard, Yves; Hamelin, Benoit [Ecole Polytechnique de Montreal, Montreal, QC (Canada). Inst. de Genie Biomedical; Dussault, Jean-Pierre [Sherbrooke Univ., Sherbrooke, QC (Canada). Dept. d' Informatique; Beaudoin, Gilles; Cloutier, Guy; Chartrand-Lefebvre, Carl; Hadjadj, Sofiane; Soulez, Gilles [Montreal Univ., Hopital Notre-Dame, Montreal, QC (Canada). Centre de Recherche du Centre Hospitalier

    2011-07-01

    We present the implementation of a iterative reconstruction algorithm for 3D helical computed tomography. The main difficulties of helical CT reconstruction are the large memory footprint of the tools and data involved, as well as the very long runtime of the iterative methods. The proposed solution hinges on the following three features: (1) a multiple-ray-driven projection operator with a parsimonious representation; (2) a targeted reconstruction framework that restricts the iterative reconstruction effort to a region of interest within the imaged volume; (3) the choice of a fast convergent solver for the nonlinear reconstruction problem. Results on clinical-size data show significant improvement in image quality over the default scanner reconstruction and an acceptable computation cost. (orig.)

  3. Study of CT-based positron range correction in high resolution 3D PET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Cal-Gonzalez, J., E-mail: jacobo@nuclear.fis.ucm.es [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Herraiz, J.L. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Espana, S. [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Vicente, E. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Instituto de Estructura de la Materia, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid (Spain); Herranz, E. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain); Desco, M. [Unidad de Medicina y Cirugia Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain); Vaquero, J.J. [Dpto. de Bioingenieria e Ingenieria Espacial, Universidad Carlos III, Madrid (Spain); Udias, J.M. [Grupo de Fisica Nuclear, Dpto. Fisica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid (Spain)

    2011-08-21

    Positron range limits the spatial resolution of PET images and has a different effect for different isotopes and positron propagation materials. Therefore it is important to consider it during image reconstruction, in order to obtain optimal image quality. Positron range distributions for most common isotopes used in PET in different materials were computed using the Monte Carlo simulations with PeneloPET. The range profiles were introduced into the 3D OSEM image reconstruction software FIRST and employed to blur the image either in the forward projection or in the forward and backward projection. The blurring introduced takes into account the different materials in which the positron propagates. Information on these materials may be obtained, for instance, from a segmentation of a CT image. The results of introducing positron blurring in both forward and backward projection operations was compared to using it only during forward projection. Further, the effect of different shapes of positron range profile in the quality of the reconstructed images with positron range correction was studied. For high positron energy isotopes, the reconstructed images show significant improvement in spatial resolution when positron range is taken into account during reconstruction, compared to reconstructions without positron range modeling.

  4. Construction of Realistic Liver Phantoms from Patient Images using 3D Printer and Its Application in CT Image Quality Assessment.

    Science.gov (United States)

    Leng, Shuai; Yu, Lifeng; Vrieze, Thomas; Kuhlmann, Joel; Chen, Baiyu; McCollough, Cynthia H

    2015-01-01

    The purpose of this study is to use 3D printing techniques to construct a realistic liver phantom with heterogeneous background and anatomic structures from patient CT images, and to use the phantom to assess image quality with filtered backprojection and iterative reconstruction algorithms. Patient CT images were segmented into liver tissues, contrast-enhanced vessels, and liver lesions using commercial software, based on which stereolithography (STL) files were created and sent to a commercial 3D printer. A 3D liver phantom was printed after assigning different printing materials to each object to simulate appropriate attenuation of each segmented object. As high opacity materials are not available for the printer, we printed hollow vessels and filled them with iodine solutions of adjusted concentration to represent enhance levels in contrast-enhanced liver scans. The printed phantom was then placed in a 35×26 cm oblong-shaped water phantom and scanned repeatedly at 4 dose levels. Images were reconstructed using standard filtered backprojection and an iterative reconstruction algorithm with 3 different strength settings. Heterogeneous liver background were observed from the CT images and the difference in CT numbers between lesions and background were representative for low contrast lesions in liver CT studies. CT numbers in vessels filled with iodine solutions represented the enhancement of liver arteries and veins. Images were run through a Channelized Hotelling model observer with Garbor channels and ROC analysis was performed. The AUC values showed performance improvement using the iterative reconstruction algorithm and the amount of improvement increased with strength setting.

  5. Construction of realistic liver phantoms from patient images using 3D printer and its application in CT image quality assessment

    Science.gov (United States)

    Leng, Shuai; Yu, Lifeng; Vrieze, Thomas; Kuhlmann, Joel; Chen, Baiyu; McCollough, Cynthia H.

    2015-03-01

    The purpose of this study is to use 3D printing techniques to construct a realistic liver phantom with heterogeneous background and anatomic structures from patient CT images, and to use the phantom to assess image quality with filtered back-projection and iterative reconstruction algorithms. Patient CT images were segmented into liver tissues, contrast-enhanced vessels, and liver lesions using commercial software, based on which stereolithography (STL) files were created and sent to a commercial 3D printer. A 3D liver phantom was printed after assigning different printing materials to each object to simulate appropriate attenuation of each segmented object. As high opacity materials are not available for the printer, we printed hollow vessels and filled them with iodine solutions of adjusted concentration to represent enhance levels in contrast-enhanced liver scans. The printed phantom was then placed in a 35×26 cm oblong-shaped water phantom and scanned repeatedly at 4 dose levels. Images were reconstructed using standard filtered back-projection and an iterative reconstruction algorithm with 3 different strength settings. Heterogeneous liver background were observed from the CT images and the difference in CT numbers between lesions and background were representative for low contrast lesions in liver CT studies. CT numbers in vessels filled with iodine solutions represented the enhancement of liver arteries and veins. Images were run through a Channelized Hotelling model observer with Garbor channels and ROC analysis was performed. The AUC values showed performance improvement using the iterative reconstruction algorithm and the amount of improvement increased with strength setting.

  6. Quantitative analysis of spinal curvature in 3D: application to CT images of normal spine

    Energy Technology Data Exchange (ETDEWEB)

    Vrtovec, Tomaz; Likar, Bostjan; Pernus, Franjo [University of Ljubljana, Faculty of Electrical Engineering, Trzaska 25, SI-1000 Ljubljana (Slovenia)], E-mail: tomaz.vrtovec@fe.uni-lj.si, E-mail: bostjan.likar@fe.uni-lj.si, E-mail: franjo.pernus@fe.uni-lj.si

    2008-04-07

    The purpose of this study is to present a framework for quantitative analysis of spinal curvature in 3D. In order to study the properties of such complex 3D structures, we propose two descriptors that capture the characteristics of spinal curvature in 3D. The descriptors are the geometric curvature (GC) and curvature angle (CA), which are independent of the orientation and size of spine anatomy. We demonstrate the two descriptors that characterize the spinal curvature in 3D on 30 computed tomography (CT) images of normal spine and on a scoliotic spine. The descriptors are determined from 3D vertebral body lines, which are obtained by two different methods. The first method is based on the least-squares technique that approximates the manually identified vertebra centroids, while the second method searches for vertebra centroids in an automated optimization scheme, based on computer-assisted image analysis. Polynomial functions of the fourth and fifth degree were used for the description of normal and scoliotic spinal curvature in 3D, respectively. The mean distance to vertebra centroids was 1.1 mm ({+-}0.6 mm) for the first and 2.1 mm ({+-}1.4 mm) for the second method. The distributions of GC and CA values were obtained along the 30 images of normal spine at each vertebral level and show that maximal thoracic kyphosis (TK), thoracolumbar junction (TJ) and maximal lumbar lordosis (LL) on average occur at T3/T4, T12/L1 and L4/L5, respectively. The main advantage of GC and CA is that the measurements are independent of the orientation and size of the spine, thus allowing objective intra- and inter-subject comparisons. The positions of maximal TK, TJ and maximal LL can be easily identified by observing the GC and CA distributions at different vertebral levels. The obtained courses of the GC and CA for the scoliotic spine were compared to the distributions of GC and CA for the normal spines. The significant difference in values indicates that the descriptors of GC and

  7. Quantitative analysis of spinal curvature in 3D: application to CT images of normal spine.

    Science.gov (United States)

    Vrtovec, Tomaz; Likar, Bostjan; Pernus, Franjo

    2008-04-07

    The purpose of this study is to present a framework for quantitative analysis of spinal curvature in 3D. In order to study the properties of such complex 3D structures, we propose two descriptors that capture the characteristics of spinal curvature in 3D. The descriptors are the geometric curvature (GC) and curvature angle (CA), which are independent of the orientation and size of spine anatomy. We demonstrate the two descriptors that characterize the spinal curvature in 3D on 30 computed tomography (CT) images of normal spine and on a scoliotic spine. The descriptors are determined from 3D vertebral body lines, which are obtained by two different methods. The first method is based on the least-squares technique that approximates the manually identified vertebra centroids, while the second method searches for vertebra centroids in an automated optimization scheme, based on computer-assisted image analysis. Polynomial functions of the fourth and fifth degree were used for the description of normal and scoliotic spinal curvature in 3D, respectively. The mean distance to vertebra centroids was 1.1 mm (+/-0.6 mm) for the first and 2.1 mm (+/-1.4 mm) for the second method. The distributions of GC and CA values were obtained along the 30 images of normal spine at each vertebral level and show that maximal thoracic kyphosis (TK), thoracolumbar junction (TJ) and maximal lumbar lordosis (LL) on average occur at T3/T4, T12/L1 and L4/L5, respectively. The main advantage of GC and CA is that the measurements are independent of the orientation and size of the spine, thus allowing objective intra- and inter-subject comparisons. The positions of maximal TK, TJ and maximal LL can be easily identified by observing the GC and CA distributions at different vertebral levels. The obtained courses of the GC and CA for the scoliotic spine were compared to the distributions of GC and CA for the normal spines. The significant difference in values indicates that the descriptors of GC and CA

  8. Registration of 6-DOFs electrogoniometry and CT medical imaging for 3D joint modeling.

    Science.gov (United States)

    Van Sint Jan, S; Salvia, P; Hilal, I; Sholukha, V; Rooze, M; Clapworthy, G

    2002-11-01

    The paper describes a method in which two data-collecting systems, medical imaging and electrogoniometry, are combined to allow the accurate and simultaneous modeling of both the spatial kinematics and the morphological surface of a particular joint. The joint of interest (JOI) is attached to a Plexiglas jig that includes four metallic markers defining a local reference system (R(GONIO)) for the kinematics data. Volumetric data of the JOI and the R(GONIO) markers are collected from medical imaging. The spatial location and orientation of the markers in the global reference system (R(CT)) of the medical-imaging environment are obtained by applying object-recognition and classification methods on the image dataset. Segmentation and 3D isosurfacing of the JOI are performed to produce a 3D model including two anatomical objects-the proximal and distal JOI segments. After imaging, one end of a custom-made 3D electrogoniometer is attached to the distal segment of the JOI, and the other end is placed at the R(GONIO) origin; the JOI is displaced and the spatial kinematics data is recorded by the goniometer. After recording, data registration from R(GONIO) to R(CT) occurred prior to simulation. Data analysis was performed using both joint coordinate system (JCS) and instantaneous helical axis (IHA).Finally, the 3D joint model is simulated in real time using the experimental kinematics data. The system is integrated into a computer graphics interface, allowing free manipulation of the 3D scene. The overall accuracy of the method has been validated with two other kinematics data collection methods including a 3D digitizer and interpolation of the kinematics data from discrete positions obtained from medical imaging. Validation has been performed on both superior and inferior radio-ulna joints (i.e. prono-supination motion). Maximal RMS error was 1 degrees and 1.2mm on the helical axis rotation and translation, respectively. Prono-supination of the forearm showed a total

  9. Piecewise-diffeomorphic image registration: application to the motion estimation between 3D CT lung images with sliding conditions.

    Science.gov (United States)

    Risser, Laurent; Vialard, François-Xavier; Baluwala, Habib Y; Schnabel, Julia A

    2013-02-01

    In this paper, we propose a new strategy for modelling sliding conditions when registering 3D images in a piecewise-diffeomorphic framework. More specifically, our main contribution is the development of a mathematical formalism to perform Large Deformation Diffeomorphic Metric Mapping registration with sliding conditions. We also show how to adapt this formalism to the LogDemons diffeomorphic registration framework. We finally show how to apply this strategy to estimate the respiratory motion between 3D CT pulmonary images. Quantitative tests are performed on 2D and 3D synthetic images, as well as on real 3D lung images from the MICCAI EMPIRE10 challenge. Results show that our strategy estimates accurate mappings of entire 3D thoracic image volumes that exhibit a sliding motion, as opposed to conventional registration methods which are not capable of capturing discontinuous deformations at the thoracic cage boundary. They also show that although the deformations are not smooth across the location of sliding conditions, they are almost always invertible in the whole image domain. This would be helpful for radiotherapy planning and delivery.

  10. Three-dimensional analysis of alveolar bone resorption by image processing of 3-D dental CT images

    Science.gov (United States)

    Nagao, Jiro; Kitasaka, Takayuki; Mori, Kensaku; Suenaga, Yasuhito; Yamada, Shohzoh; Naitoh, Munetaka

    2006-03-01

    We have developed a novel system that provides total support for assessment of alveolar bone resorption, caused by periodontitis, based on three-dimensional (3-D) dental CT images. In spite of the difficulty in perceiving the complex 3-D shape of resorption, dentists assessing resorption location and severity have been relying on two-dimensional radiography and probing, which merely provides one-dimensional information (depth) about resorption shape. However, there has been little work on assisting assessment of the disease by 3-D image processing and visualization techniques. This work provides quantitative evaluation results and figures for our system that measures the three-dimensional shape and spread of resorption. It has the following functions: (1) measures the depth of resorption by virtually simulating probing in the 3-D CT images, taking advantage of image processing of not suffering obstruction by teeth on the inter-proximal sides and much smaller measurement intervals than the conventional examination; (2) visualizes the disposition of the depth by movies and graphs; (3) produces a quantitative index and intuitive visual representation of the spread of resorption in the inter-radicular region in terms of area; and (4) calculates the volume of resorption as another severity index in the inter-radicular region and the region outside it. Experimental results in two cases of 3-D dental CT images and a comparison of the results with the clinical examination results and experts' measurements of the corresponding patients confirmed that the proposed system gives satisfying results, including 0.1 to 0.6mm of resorption measurement (probing) error and fairly intuitive presentation of measurement and calculation results.

  11. Adaptive Iterative Dose Reduction Using Three Dimensional Processing (AIDR3D improves chest CT image quality and reduces radiation exposure.

    Directory of Open Access Journals (Sweden)

    Tsuneo Yamashiro

    Full Text Available To assess the advantages of Adaptive Iterative Dose Reduction using Three Dimensional Processing (AIDR3D for image quality improvement and dose reduction for chest computed tomography (CT.Institutional Review Boards approved this study and informed consent was obtained. Eighty-eight subjects underwent chest CT at five institutions using identical scanners and protocols. During a single visit, each subject was scanned using different tube currents: 240, 120, and 60 mA. Scan data were converted to images using AIDR3D and a conventional reconstruction mode (without AIDR3D. Using a 5-point scale from 1 (non-diagnostic to 5 (excellent, three blinded observers independently evaluated image quality for three lung zones, four patterns of lung disease (nodule/mass, emphysema, bronchiolitis, and diffuse lung disease, and three mediastinal measurements (small structure visibility, streak artifacts, and shoulder artifacts. Differences in these scores were assessed by Scheffe's test.At each tube current, scans using AIDR3D had higher scores than those without AIDR3D, which were significant for lung zones (p<0.0001 and all mediastinal measurements (p<0.01. For lung diseases, significant improvements with AIDR3D were frequently observed at 120 and 60 mA. Scans with AIDR3D at 120 mA had significantly higher scores than those without AIDR3D at 240 mA for lung zones and mediastinal streak artifacts (p<0.0001, and slightly higher or equal scores for all other measurements. Scans with AIDR3D at 60 mA were also judged superior or equivalent to those without AIDR3D at 120 mA.For chest CT, AIDR3D provides better image quality and can reduce radiation exposure by 50%.

  12. How accurate are the fusion of cone-beam CT and 3-D stereophotographic images?

    Directory of Open Access Journals (Sweden)

    Yasas S N Jayaratne

    Full Text Available BACKGROUND: Cone-beam Computed Tomography (CBCT and stereophotography are two of the latest imaging modalities available for three-dimensional (3-D visualization of craniofacial structures. However, CBCT provides only limited information on surface texture. This can be overcome by combining the bone images derived from CBCT with 3-D photographs. The objectives of this study were 1 to evaluate the feasibility of integrating 3-D Photos and CBCT images 2 to assess degree of error that may occur during the above processes and 3 to identify facial regions that would be most appropriate for 3-D image registration. METHODOLOGY: CBCT scans and stereophotographic images from 29 patients were used for this study. Two 3-D images corresponding to the skin and bone were extracted from the CBCT data. The 3-D photo was superimposed on the CBCT skin image using relatively immobile areas of the face as a reference. 3-D colour maps were used to assess the accuracy of superimposition were distance differences between the CBCT and 3-D photo were recorded as the signed average and the Root Mean Square (RMS error. PRINCIPAL FINDINGS: The signed average and RMS of the distance differences between the registered surfaces were -0.018 (±0.129 mm and 0.739 (±0.239 mm respectively. The most errors were found in areas surrounding the lips and the eyes, while minimal errors were noted in the forehead, root of the nose and zygoma. CONCLUSIONS: CBCT and 3-D photographic data can be successfully fused with minimal errors. When compared to RMS, the signed average was found to under-represent the registration error. The virtual 3-D composite craniofacial models permit concurrent assessment of bone and soft tissues during diagnosis and treatment planning.

  13. 3D movement correction of CT brain perfusion image data of patients with acute ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Fahmi, Fahmi [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); University of Sumatera Utara, Department of Electrical Engineering, Medan (Indonesia); Marquering, Henk A.; Streekstra, Geert J. [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Borst, Jordi; Beenen, Ludo F.M.; Majoie, Charles B.L. [Academic Medical Center, Department of Radiology, Amsterdam (Netherlands); Niesten, Joris M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); VanBavel, Ed [Academic Medical Center, Department of Biomedical Engineering and Physics, Amsterdam (Netherlands); Collaboration: on behalf of the DUST study

    2014-06-15

    Head movement during CT brain perfusion (CTP) acquisition can deteriorate the accuracy of CTP analysis. Most CTP software packages can only correct in-plane movement and are limited to small ranges. The purpose of this study is to validate a novel 3D correction method for head movement during CTP acquisition. Thirty-five CTP datasets that were classified as defective due to head movement were included in this study. All CTP time frames were registered with non-contrast CT data using a 3D rigid registration method. Location and appearance of ischemic area in summary maps derived from original and registered CTP datasets were qualitative compared with follow-up non-contrast CT. A quality score (QS) of 0 to 3 was used to express the degree of agreement. Furthermore, experts compared the quality of both summary maps and assigned the improvement score (IS) of the CTP analysis, ranging from -2 (much worse) to 2 (much better). Summary maps generated from corrected CTP significantly agreed better with appearance of infarct on follow-up CT with mean QS 2.3 versus mean QS 1.8 for summary maps from original CTP (P = 0.024). In comparison to original CTP data, correction resulted in a quality improvement with average IS 0.8: 17 % worsened (IS = -2, -1), 20 % remained unchanged (IS = 0), and 63 % improved (IS = +1, +2). The proposed 3D movement correction improves the summary map quality for CTP datasets with severe head movement. (orig.)

  14. A LabVIEW based user-friendly nano-CT image alignment and 3D reconstruction platform

    CERN Document Server

    Wang, Shenghao; Wang, Zhili; Gao, Kun; Wu, Zhao; Zhu, Peiping; Wu, Ziyu

    2014-01-01

    X-ray nanometer computed tomography (nano-CT) offers applications and opportunities in many scientific researches and industrial areas. Here we present a user-friendly and fast LabVIEW based package running, after acquisition of the raw projection images, a procedure to obtain the inner structure of the sample under analysis. At first, a reliable image alignment procedure fixes possible misalignments among image series due to mechanical errors, thermal expansion and other external contributions, then a novel fast parallel beam 3D reconstruction performs the tomographic reconstruction. The remarkable improved reconstruction after the image calibration confirms the fundamental role of the image alignment procedure. It minimizes blurring and additional streaking artifacts present in a reconstructed slice that cause loss of information and faked structures in the observed material. The nano-CT image alignment and 3D reconstruction LabVIEW package significantly reducing the data process, makes faster and easier th...

  15. Integration of 3D anatomical data obtained by CT imaging and 3D optical scanning for computer aided implant surgery

    OpenAIRE

    Paoli Alessandro; Barone Sandro; Chessa Giacomo; Frisardi Gianni; Razionale Armando; Frisardi Flavio

    2011-01-01

    Abstract Background A precise placement of dental implants is a crucial step to optimize both prosthetic aspects and functional constraints. In this context, the use of virtual guiding systems has been recognized as a fundamental tool to control the ideal implant position. In particular, complex periodontal surgeries can be performed using preoperative planning based on CT data. The critical point of the procedure relies on the lack of accuracy in transferring CT planning information to surgi...

  16. Self-calibration of cone-beam CT geometry using 3D-2D image registration

    Science.gov (United States)

    Ouadah, S.; Stayman, J. W.; Gang, G. J.; Ehtiati, T.; Siewerdsen, J. H.

    2016-04-01

    Robotic C-arms are capable of complex orbits that can increase field of view, reduce artifacts, improve image quality, and/or reduce dose; however, it can be challenging to obtain accurate, reproducible geometric calibration required for image reconstruction for such complex orbits. This work presents a method for geometric calibration for an arbitrary source-detector orbit by registering 2D projection data to a previously acquired 3D image. It also yields a method by which calibration of simple circular orbits can be improved. The registration uses a normalized gradient information similarity metric and the covariance matrix adaptation-evolution strategy optimizer for robustness against local minima and changes in image content. The resulting transformation provides a ‘self-calibration’ of system geometry. The algorithm was tested in phantom studies using both a cone-beam CT (CBCT) test-bench and a robotic C-arm (Artis Zeego, Siemens Healthcare) for circular and non-circular orbits. Self-calibration performance was evaluated in terms of the full-width at half-maximum (FWHM) of the point spread function in CBCT reconstructions, the reprojection error (RPE) of steel ball bearings placed on each phantom, and the overall quality and presence of artifacts in CBCT images. In all cases, self-calibration improved the FWHM—e.g. on the CBCT bench, FWHM  =  0.86 mm for conventional calibration compared to 0.65 mm for self-calibration (p  <  0.001). Similar improvements were measured in RPE—e.g. on the robotic C-arm, RPE  =  0.73 mm for conventional calibration compared to 0.55 mm for self-calibration (p  <  0.001). Visible improvement was evident in CBCT reconstructions using self-calibration, particularly about high-contrast, high-frequency objects (e.g. temporal bone air cells and a surgical needle). The results indicate that self-calibration can improve even upon systems with presumably accurate geometric calibration and is

  17. Volume change determination of metastatic lung tumors in CT images using 3-D template matching

    Science.gov (United States)

    Ambrosini, Robert D.; Wang, Peng; O'Dell, Walter G.

    2009-02-01

    The ability of a clinician to properly detect changes in the size of lung nodules over time is a vital element to both the diagnosis of malignant growths and the monitoring of the response of cancerous lesions to therapy. We have developed a novel metastasis sizing algorithm based on 3-D template matching with spherical tumor appearance models that were created to match the expected geometry of the tumors of interest while accounting for potential spatial offsets of nodules in the slice thickness direction. The spherical template that best-fits the overall volume of each lung metastasis was determined through the optimization of the 3-D normalized cross-correlation coefficients (NCCC) calculated between the templates and the nodules. A total of 17 different lung metastases were extracted manually from real patient CT datasets and reconstructed in 3-D using spherical harmonics equations to generate simulated nodules for testing our algorithm. Each metastasis 3-D shape was then subjected to 10%, 25%, 50%, 75% and 90% scaling of its volume to allow for 5 possible volume change combinations relative to the original size per each reconstructed nodule and inserted back into CT datasets with appropriate blurring and noise addition. When plotted against the true volume change, the nodule volume changes calculated by our algorithm for these 85 data points exhibited a high degree of accuracy (slope = 0.9817, R2 = 0.9957). Our results demonstrate that the 3-D template matching method can be an effective, fast, and accurate tool for automated sizing of metastatic tumors.

  18. Multi-detector CT and 3D imaging in a multi-vendor PACS environment

    NARCIS (Netherlands)

    van Ooijen, PMA; Witkamp, R; Oudkerk, M; Lemke, HU; Inamura, K; Doi, K; Vannier, MW; Farman, AG; Reiber, JHC

    2003-01-01

    Introduction of new hard- and software techniques like Multi-Dectector Computed Tomography (MDCT) and 3D imaging has put new demands on the Picture Archiving and Communications System (PACS) environment within the radiology department. The daily use of these new techniques requires a good integratio

  19. A normalized thoracic coordinate system for atlas mapping in 3D CT images

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this paper, a normalized thoracic coordinate system (NTCS) is defined for rapidly mapping the 4D thoracic organ atlas into individual CT volume images. This coordinate system is defined based on the thoracic skeleton. The coordinate values are normalized by the size of the individual thorax so that this coordinate system is universal to different individuals. For compensating the respiratory motion of the organs, a 4D dynamic torso atlas is introduced. A method for mapping this dynamic atlas into the individual image using the NTCS is also proposed. With this method, the dynamic atlas was mapped into the clinical thoracic CT images and rough positions of the organs were found rapidly. This NTCS-based 4D atlas mapping method may provide a novel way for estimating the thoracic organ positions in low-resolution molecular imaging modalities, as well as in modern 4D medical images.

  20. Rigid Registration of Freehand 3D Ultrasound and CT-Scan Kidney Images

    CERN Document Server

    Leroy, A; Payan, Y; Troccaz, J; Leroy, Antoine; Mozer, Pierre; Payan, Yohan; Troccaz, Jocelyne

    2004-01-01

    This paper presents a method to register a preoperative CT volume to a sparse set of intraoperative US slices. In the context of percutaneous renal puncture, the aim is to transfer a planning information to an intraoperative coordinate system. The spatial position of the US slices is measured by localizing a calibrated probe. Our method consists in optimizing a rigid 6 degree of freedom (DOF) transform by evaluating at each step the similarity between the set of US images and the CT volume. The images have been preprocessed in order to increase the relationship between CT and US pixels. Correlation Ratio turned out to be the most accurate and appropriate similarity measure to be used in a Powell-Brent minimization scheme. Results are compared to a standard rigid point-to-point registration involving segmentation, and discussed.

  1. US-CT 3D dual imaging by mutual display of the same sections for depicting minor changes in hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Hiroyuki, E-mail: fukuhiro1962@hotmail.com [International HIFU Center, Sanmu Medical Center Hospital, Naruto 167, Sanbu-shi, Chiba 289-1326 (Japan); Ito, Ryu; Ohto, Masao; Sakamoto, Akio [International HIFU Center, Sanmu Medical Center Hospital, Naruto 167, Sanbu-shi, Chiba 289-1326 (Japan); Otsuka, Masayuki; Togawa, Akira; Miyazaki, Masaru [Department of General Surgery, Graduate School of Medicine, Chiba University, Inohana 1-8-1, Chuo-ku, Chiba-shi, Chiba 260-0856 (Japan); Yamagata, Hitoshi [Toshiba Medical Systems Corporation, Otawara 324-0036 (Japan)

    2012-09-15

    The purpose of this study was to evaluate the usefulness of ultrasound-computed tomography (US-CT) 3D dual imaging for the detection of small extranodular growths of hepatocellular carcinoma (HCC). The clinical and pathological profiles of 10 patients with single nodular type HCC with extranodular growth (extranodular growth) who underwent a hepatectomy were evaluated using two-dimensional (2D) ultrasonography (US), three-dimensional (3D) US, 3D computed tomography (CT) and 3D US-CT dual images. Raw 3D data was converted to DICOM (Digital Imaging and Communication in Medicine) data using Echo to CT (Toshiba Medical Systems Corp., Tokyo, Japan), and the 3D DICOM data was directly transferred to the image analysis system (ZioM900, ZIOSOFT Inc., Tokyo, Japan). By inputting the angle number (x, y, z) of the 3D CT volume data into the ZioM900, multiplanar reconstruction (MPR) images of the 3D CT data were displayed in a manner such that they resembled the conventional US images. Eleven extranodular growths were detected pathologically in 10 cases. 2D US was capable of depicting only 2 of the 11 extranodular growths. 3D CT was capable of depicting 4 of the 11 extranodular growths. On the other hand, 3D US was capable of depicting 10 of the 11 extranodular growths, and 3D US-CT dual images, which enable the dual analysis of the CT and US planes, revealed all 11 extranodular growths. In conclusion, US-CT 3D dual imaging may be useful for the detection of small extranodular growths.

  2. Combining population and patient-specific characteristics for prostate segmentation on 3D CT images

    Science.gov (United States)

    Ma, Ling; Guo, Rongrong; Tian, Zhiqiang; Venkataraman, Rajesh; Sarkar, Saradwata; Liu, Xiabi; Tade, Funmilayo; Schuster, David M.; Fei, Baowei

    2016-03-01

    Prostate segmentation on CT images is a challenging task. In this paper, we explore the population and patient-specific characteristics for the segmentation of the prostate on CT images. Because population learning does not consider the inter-patient variations and because patient-specific learning may not perform well for different patients, we are combining the population and patient-specific information to improve segmentation performance. Specifically, we train a population model based on the population data and train a patient-specific model based on the manual segmentation on three slice of the new patient. We compute the similarity between the two models to explore the influence of applicable population knowledge on the specific patient. By combining the patient-specific knowledge with the influence, we can capture the population and patient-specific characteristics to calculate the probability of a pixel belonging to the prostate. Finally, we smooth the prostate surface according to the prostate-density value of the pixels in the distance transform image. We conducted the leave-one-out validation experiments on a set of CT volumes from 15 patients. Manual segmentation results from a radiologist serve as the gold standard for the evaluation. Experimental results show that our method achieved an average DSC of 85.1% as compared to the manual segmentation gold standard. This method outperformed the population learning method and the patient-specific learning approach alone. The CT segmentation method can have various applications in prostate cancer diagnosis and therapy.

  3. Twin robotic x-ray system for 2D radiographic and 3D cone-beam CT imaging

    Science.gov (United States)

    Fieselmann, Andreas; Steinbrener, Jan; Jerebko, Anna K.; Voigt, Johannes M.; Scholz, Rosemarie; Ritschl, Ludwig; Mertelmeier, Thomas

    2016-03-01

    In this work, we provide an initial characterization of a novel twin robotic X-ray system. This system is equipped with two motor-driven telescopic arms carrying X-ray tube and flat-panel detector, respectively. 2D radiographs and fluoroscopic image sequences can be obtained from different viewing angles. Projection data for 3D cone-beam CT reconstruction can be acquired during simultaneous movement of the arms along dedicated scanning trajectories. We provide an initial evaluation of the 3D image quality based on phantom scans and clinical images. Furthermore, initial evaluation of patient dose is conducted. The results show that the system delivers high image quality for a range of medical applications. In particular, high spatial resolution enables adequate visualization of bone structures. This system allows 3D X-ray scanning of patients in standing and weight-bearing position. It could enable new 2D/3D imaging workflows in musculoskeletal imaging and improve diagnosis of musculoskeletal disorders.

  4. 2D and 3D Terahertz Imaging and X-Rays CT for Sigillography Study

    Science.gov (United States)

    Fabre, M.; Durand, R.; Bassel, L.; Recur, B.; Balacey, H.; Bou Sleiman, J.; Perraud, J.-B.; Mounaix, P.

    2017-04-01

    Seals are part of our cultural heritage but the study of these objects is limited because of their fragility. Terahertz and X-Ray imaging are used to analyze a collection of wax seals from the fourteenth to eighteenth centuries. In this work, both techniques are compared in order to discuss their advantages and limits and their complementarity for conservation state study of the samples. Thanks to 3D analysis and reconstructions, defects and fractures are detected with an estimation of their depth position. The path from the parchment tongue inside the seals is also detected.

  5. Iterative mesh transformation for 3D segmentation of livers with cancers in CT images.

    Science.gov (United States)

    Lu, Difei; Wu, Yin; Harris, Gordon; Cai, Wenli

    2015-07-01

    Segmentation of diseased liver remains a challenging task in clinical applications due to the high inter-patient variability in liver shapes, sizes and pathologies caused by cancers or other liver diseases. In this paper, we present a multi-resolution mesh segmentation algorithm for 3D segmentation of livers, called iterative mesh transformation that deforms the mesh of a region-of-interest (ROI) in a progressive manner by iterations between mesh transformation and contour optimization. Mesh transformation deforms the 3D mesh based on the deformation transfer model that searches the optimal mesh based on the affine transformation subjected to a set of constraints of targeting vertices. Besides, contour optimization searches the optimal transversal contours of the ROI by applying the dynamic-programming algorithm to the intersection polylines of the 3D mesh on 2D transversal image planes. The initial constraint set for mesh transformation can be defined by a very small number of targeting vertices, namely landmarks, and progressively updated by adding the targeting vertices selected from the optimal transversal contours calculated in contour optimization. This iterative 3D mesh transformation constrained by 2D optimal transversal contours provides an efficient solution to a progressive approximation of the mesh of the targeting ROI. Based on this iterative mesh transformation algorithm, we developed a semi-automated scheme for segmentation of diseased livers with cancers using as little as five user-identified landmarks. The evaluation study demonstrates that this semi-automated liver segmentation scheme can achieve accurate and reliable segmentation results with significant reduction of interaction time and efforts when dealing with diseased liver cases.

  6. Detection of tibial condylar fractures using 3D imaging with a mobile image amplifier (Siemens ISO-C-3D): Comparison with plain films and spiral CT; Frakturdiagnostik am Kniegelenk mit einem neuen mobilen CT-System (ISO-C-3D): Vergleich mit konventionellem Roentgen und Spiral-CT

    Energy Technology Data Exchange (ETDEWEB)

    Kotsianos, D.; Rock, C.; Wirth, S.; Linsenmaier, U.; Brandl, R.; Fischer, T.; Pfeifer, K.J.; Reiser, M. [Klinikum der Universitaet Muenchen-Innenstadt, Muenchen (Germany). Inst. fuer Klinische Radiologie; Euler, E.; Mutschler, W. [Klinikum der Universitaet Muenchen-Innenstadt, Muenchen (Germany). Chirurgische Klinik und Poliklinik

    2002-01-01

    Purpose: To analyze a prototype mobile C-arm 3D image amplifier in the detection and classification of experimental tibial condylar fractures with multiplanar reconstructions (MPR). Method: Human knee specimens (n=22) with tibial condylar fractures were examined with a prototype C-arm (ISO-C-3D, Siemens AG), plain films (CR) and spiral CT (CT). The motorized C-arm provides fluoroscopic images during a 190 orbital rotation computing a 119 mm data cube. From these 3D data sets MP reconstructions were obtained. All images were evaluated by four independent readers for the detection and assessment of fracture lines. All fractures were classified according to the Mueller AO classification. To confirm the results, the specimens were finally surgically dissected. Results: 97% of the tibial condylar fractures were easily seen and correctly classified according to the Mueller AO classification on MP reconstruction of the ISO-C-3D. There is no significant difference between ISO-C and CT in detection and correct classification of fractures, but ISO-CD-3D is significant by better than CR. (orig.) [German] Zielsetzung: Ziel der vorliegenden Studie war es, die diagnostischen Moeglichkeiten und Grenzen der Erkennbarkeit und Klassifizierung von Frakturen mit multiplanaren Rekonstruktionen (MPR) aus 3D-Datensaetzen eines fahrbaren C-Bogengeraetes an Kniegelenken zu pruefen. Methodik: Kniegelenke von Verstorbenen (n=22) mit Tibiakopffrakturen wurden an einem Prototyp eines mobilen C-Bogen Schnittbild-/Durchleuchtungsgeraets (ISO-C-3D, Siemens AG Erlangen) untersucht. Das Geraet erzeugt waehrend einer einmaligen 190-Grad-Rotation 100 Projektionsaufnahmen, aus denen ein 3D-Volumendatensatz gewonnen wird. Aus diesem werden Hochkontrastschnittbilder als MP-Rekonstruktionen in allen drei Raumebenen errechnet und visualisiert. Die Kniegelenke wurden von 4 unabhaengigen Befundern hinsichtlich Frakturerkennbarkeit, Frakturart und -ausmass unter Verwendung der MP

  7. A visual data-mining approach using 3D thoracic CT images for classification between benign and malignant pulmonary nodules

    Science.gov (United States)

    Kawata, Yoshiki; Niki, Noboru; Ohamatsu, Hironobu; Kusumoto, Masahiko; Kakinuma, Ryutaro; Mori, Kiyoshi; Yamada, K.; Nishiyama, Hiroyuki; Eguchi, Kenji; Kaneko, Masahiro; Moriyama, Noriyuki

    2003-05-01

    This paper presents a visual data-mining approach to assist physicians for classification between benign and malignant pulmonary nodules. This approach retrieves and displays nodules which exhibit morphological and internal profiles consistent to the nodule in question. It uses a three-dimensional (3-D) CT image database of pulmonary nodules for which diagnosis is known. The central module in this approach makes possible analysis of the query nodule image and extraction of the features of interest: shape, surrounding structure, and internal structure of the nodules. The nodule shape is characterized by principal axes, while the surrounding and internal structure is represented by the distribution pattern of CT density and 3-D curvature indexes. The nodule representation is then applied to a similarity measure such as a correlation coefficient. For each query case, we sort all the nodules of the database from most to less similar ones. By applying the retrieval method to our database, we present its feasibility to search the similar 3-D nodule images.

  8. Towards real-time 3D US to CT bone image registration using phase and curvature feature based GMM matching.

    Science.gov (United States)

    Brounstein, Anna; Hacihaliloglu, Ilker; Guy, Pierre; Hodgson, Antony; Abugharbieh, Rafeef

    2011-01-01

    In order to use pre-operatively acquired computed tomography (CT) scans to guide surgical tool movements in orthopaedic surgery, the CT scan must first be registered to the patient's anatomy. Three-dimensional (3D) ultrasound (US) could potentially be used for this purpose if the registration process could be made sufficiently automatic, fast and accurate, but existing methods have difficulties meeting one or more of these criteria. We propose a near-real-time US-to-CT registration method that matches point clouds extracted from local phase images with points selected in part on the basis of local curvature. The point clouds are represented as Gaussian Mixture Models (GMM) and registration is achieved by minimizing the statistical dissimilarity between the GMMs using an L2 distance metric. We present quantitative and qualitative results on both phantom and clinical pelvis data and show a mean registration time of 2.11 s with a mean accuracy of 0.49 mm.

  9. A user-friendly nano-CT image alignment and 3D reconstruction platform based on LabVIEW

    Science.gov (United States)

    Wang, Sheng-Hao; Zhang, Kai; Wang, Zhi-Li; Gao, Kun; Wu, Zhao; Zhu, Pei-Ping; Wu, Zi-Yu

    2015-01-01

    X-ray computed tomography at the nanometer scale (nano-CT) offers a wide range of applications in scientific and industrial areas. Here we describe a reliable, user-friendly, and fast software package based on LabVIEW that may allow us to perform all procedures after the acquisition of raw projection images in order to obtain the inner structure of the investigated sample. A suitable image alignment process to address misalignment problems among image series due to mechanical manufacturing errors, thermal expansion, and other external factors has been considered, together with a novel fast parallel beam 3D reconstruction procedure that was developed ad hoc to perform the tomographic reconstruction. We have obtained remarkably improved reconstruction results at the Beijing Synchrotron Radiation Facility after the image calibration, the fundamental role of this image alignment procedure was confirmed, which minimizes the unwanted blurs and additional streaking artifacts that are always present in reconstructed slices. Moreover, this nano-CT image alignment and its associated 3D reconstruction procedure are fully based on LabVIEW routines, significantly reducing the data post-processing cycle, thus making the activity of the users faster and easier during experimental runs.

  10. 3D segmentation of abdominal aorta from CT-scan and MR images.

    Science.gov (United States)

    Duquette, Anthony Adam; Jodoin, Pierre-Marc; Bouchot, Olivier; Lalande, Alain

    2012-06-01

    We designed a generic method for segmenting the aneurismal sac of an abdominal aortic aneurysm (AAA) both from multi-slice MR and CT-scan examinations. It is a semi-automatic method requiring little human intervention and based on graph cut theory to segment the lumen interface and the aortic wall of AAAs. Our segmentation method works independently on MRI and CT-scan volumes and has been tested on a 44 patient dataset and 10 synthetic images. Segmentation and maximum diameter estimation were compared to manual tracing from 4 experts. An inter-observer study was performed in order to measure the variability range of a human observer. Based on three metrics (the maximum aortic diameter, the volume overlap and the Hausdorff distance) the variability of the results obtained by our method is shown to be similar to that of a human operator, both for the lumen interface and the aortic wall. As will be shown, the average distance obtained with our method is less than one standard deviation away from each expert, both for healthy subjects and for patients with AAA. Our semi-automatic method provides reliable contours of the abdominal aorta from CT-scan or MRI, allowing rapid and reproducible evaluations of AAA.

  11. Pancreas segmentation from 3D abdominal CT images using patient-specific weighted subspatial probabilistic atlases

    Science.gov (United States)

    Karasawa, Kenichi; Oda, Masahiro; Hayashi, Yuichiro; Nimura, Yukitaka; Kitasaka, Takayuki; Misawa, Kazunari; Fujiwara, Michitaka; Rueckert, Daniel; Mori, Kensaku

    2015-03-01

    Abdominal organ segmentations from CT volumes are now widely used in the computer-aided diagnosis and surgery assistance systems. Among abdominal organs, the pancreas is especially difficult to segment because of its large individual differences of the shape and position. In this paper, we propose a new pancreas segmentation method from 3D abdominal CT volumes using patient-specific weighted-subspatial probabilistic atlases. First of all, we perform normalization of organ shapes in training volumes and an input volume. We extract the Volume Of Interest (VOI) of the pancreas from the training volumes and an input volume. We divide each training VOI and input VOI into some cubic regions. We use a nonrigid registration method to register these cubic regions of the training VOI to corresponding regions of the input VOI. Based on the registration results, we calculate similarities between each cubic region of the training VOI and corresponding region of the input VOI. We select cubic regions of training volumes having the top N similarities in each cubic region. We subspatially construct probabilistic atlases weighted by the similarities in each cubic region. After integrating these probabilistic atlases in cubic regions into one, we perform a rough-to-precise segmentation of the pancreas using the atlas. The results of the experiments showed that utilization of the training volumes having the top N similarities in each cubic region led good results of the pancreas segmentation. The Jaccard Index and the average surface distance of the result were 58.9% and 2.04mm on average, respectively.

  12. Efficient and robust 3D CT image reconstruction based on total generalized variation regularization using the alternating direction method.

    Science.gov (United States)

    Chen, Jianlin; Wang, Linyuan; Yan, Bin; Zhang, Hanming; Cheng, Genyang

    2015-01-01

    Iterative reconstruction algorithms for computed tomography (CT) through total variation regularization based on piecewise constant assumption can produce accurate, robust, and stable results. Nonetheless, this approach is often subject to staircase artefacts and the loss of fine details. To overcome these shortcomings, we introduce a family of novel image regularization penalties called total generalized variation (TGV) for the effective production of high-quality images from incomplete or noisy projection data for 3D reconstruction. We propose a new, fast alternating direction minimization algorithm to solve CT image reconstruction problems through TGV regularization. Based on the theory of sparse-view image reconstruction and the framework of augmented Lagrange function method, the TGV regularization term has been introduced in the computed tomography and is transformed into three independent variables of the optimization problem by introducing auxiliary variables. This new algorithm applies a local linearization and proximity technique to make the FFT-based calculation of the analytical solutions in the frequency domain feasible, thereby significantly reducing the complexity of the algorithm. Experiments with various 3D datasets corresponding to incomplete projection data demonstrate the advantage of our proposed algorithm in terms of preserving fine details and overcoming the staircase effect. The computation cost also suggests that the proposed algorithm is applicable to and is effective for CBCT imaging. Theoretical and technical optimization should be investigated carefully in terms of both computation efficiency and high resolution of this algorithm in application-oriented research.

  13. Tracking time interval changes of pulmonary nodules on follow-up 3D CT images via image-based risk score of lung cancer

    Science.gov (United States)

    Kawata, Y.; Niki, N.; Ohmatsu, H.; Kusumoto, M.; Tsuchida, T.; Eguchi, K.; Kaneko, M.; Moriyama, N.

    2013-03-01

    In this paper, we present a computer-aided follow-up (CAF) scheme to support physicians to track interval changes of pulmonary nodules on three dimensional (3D) CT images and to decide the treatment strategies without making any under or over treatment. Our scheme involves analyzing CT histograms to evaluate the volumetric distribution of CT values within pulmonary nodules. A variational Bayesian mixture modeling framework translates the image-derived features into an image-based risk score for predicting the patient recurrence-free survival. Through applying our scheme to follow-up 3D CT images of pulmonary nodules, we demonstrate the potential usefulness of the CAF scheme which can provide the trajectories that can characterize time interval changes of pulmonary nodules.

  14. 3D photoacoustic imaging

    Science.gov (United States)

    Carson, Jeffrey J. L.; Roumeliotis, Michael; Chaudhary, Govind; Stodilka, Robert Z.; Anastasio, Mark A.

    2010-06-01

    Our group has concentrated on development of a 3D photoacoustic imaging system for biomedical imaging research. The technology employs a sparse parallel detection scheme and specialized reconstruction software to obtain 3D optical images using a single laser pulse. With the technology we have been able to capture 3D movies of translating point targets and rotating line targets. The current limitation of our 3D photoacoustic imaging approach is its inability ability to reconstruct complex objects in the field of view. This is primarily due to the relatively small number of projections used to reconstruct objects. However, in many photoacoustic imaging situations, only a few objects may be present in the field of view and these objects may have very high contrast compared to background. That is, the objects have sparse properties. Therefore, our work had two objectives: (i) to utilize mathematical tools to evaluate 3D photoacoustic imaging performance, and (ii) to test image reconstruction algorithms that prefer sparseness in the reconstructed images. Our approach was to utilize singular value decomposition techniques to study the imaging operator of the system and evaluate the complexity of objects that could potentially be reconstructed. We also compared the performance of two image reconstruction algorithms (algebraic reconstruction and l1-norm techniques) at reconstructing objects of increasing sparseness. We observed that for a 15-element detection scheme, the number of measureable singular vectors representative of the imaging operator was consistent with the demonstrated ability to reconstruct point and line targets in the field of view. We also observed that the l1-norm reconstruction technique, which is known to prefer sparseness in reconstructed images, was superior to the algebraic reconstruction technique. Based on these findings, we concluded (i) that singular value decomposition of the imaging operator provides valuable insight into the capabilities of

  15. Estimation of aortic valve leaflets from 3D CT images using local shape dictionaries and linear coding

    Science.gov (United States)

    Liang, Liang; Martin, Caitlin; Wang, Qian; Sun, Wei; Duncan, James

    2016-03-01

    Aortic valve (AV) disease is a significant cause of morbidity and mortality. The preferred treatment modality for severe AV disease is surgical resection and replacement of the native valve with either a mechanical or tissue prosthetic. In order to develop effective and long-lasting treatment methods, computational analyses, e.g., structural finite element (FE) and computational fluid dynamic simulations, are very effective for studying valve biomechanics. These computational analyses are based on mesh models of the aortic valve, which are usually constructed from 3D CT images though many hours of manual annotation, and therefore an automatic valve shape reconstruction method is desired. In this paper, we present a method for estimating the aortic valve shape from 3D cardiac CT images, which is represented by triangle meshes. We propose a pipeline for aortic valve shape estimation which includes novel algorithms for building local shape dictionaries and for building landmark detectors and curve detectors using local shape dictionaries. The method is evaluated on real patient image dataset using a leave-one-out approach and achieves an average accuracy of 0.69 mm. The work will facilitate automatic patient-specific computational modeling of the aortic valve.

  16. Geometry-based vs. intensity-based medical image registration: A comparative study on 3D CT data.

    Science.gov (United States)

    Savva, Antonis D; Economopoulos, Theodore L; Matsopoulos, George K

    2016-02-01

    Spatial alignment of Computed Tomography (CT) data sets is often required in numerous medical applications and it is usually achieved by applying conventional exhaustive registration techniques, which are mainly based on the intensity of the subject data sets. Those techniques consider the full range of data points composing the data, thus negatively affecting the required processing time. Alternatively, alignment can be performed using the correspondence of extracted data points from both sets. Moreover, various geometrical characteristics of those data points can be used, instead of their chromatic properties, for uniquely characterizing each point, by forming a specific geometrical descriptor. This paper presents a comparative study reviewing variations of geometry-based, descriptor-oriented registration techniques, as well as conventional, exhaustive, intensity-based methods for aligning three-dimensional (3D) CT data pairs. In this context, three general image registration frameworks were examined: a geometry-based methodology featuring three distinct geometrical descriptors, an intensity-based methodology using three different similarity metrics, as well as the commonly used Iterative Closest Point algorithm. All techniques were applied on a total of thirty 3D CT data pairs with both known and unknown initial spatial differences. After an extensive qualitative and quantitative assessment, it was concluded that the proposed geometry-based registration framework performed similarly to the examined exhaustive registration techniques. In addition, geometry-based methods dramatically improved processing time over conventional exhaustive registration.

  17. Extraction of 3D Femur Neck Trabecular Bone Architecture from Clinical CT Images in Osteoporotic Evaluation: a Novel Framework.

    Science.gov (United States)

    Sapthagirivasan, V; Anburajan, M; Janarthanam, S

    2015-08-01

    The early detection of osteoporosis risk enhances the lifespan and quality of life of an individual. A reasonable in-vivo assessment of trabecular bone strength at the proximal femur helps to evaluate the fracture risk and henceforth, to understand the associated structural dynamics on occurrence of osteoporosis. The main aim of our study was to develop a framework to automatically determine the trabecular bone strength from clinical femur CT images and thereby to estimate its correlation with BMD. All the 50 studied south Indian female subjects aged 30 to 80 years underwent CT and DXA measurements at right femur region. Initially, the original CT slices were intensified and active contour model was utilised for the extraction of the neck region. After processing through a novel process called trabecular enrichment approach (TEA), the three dimensional (3D) trabecular features were extracted. The extracted 3D trabecular features, such as volume fraction (VF), solidity of delta points (SDP) and boundness, demonstrated a significant correlation with femoral neck bone mineral density (r = 0.551, r = 0.432, r = 0.552 respectively) at p TEA method would be useful for spotting women vulnerable to osteoporotic risk.

  18. Automated detection of retinal cell nuclei in 3D micro-CT images of zebrafish using support vector machine classification

    Science.gov (United States)

    Ding, Yifu; Tavolara, Thomas; Cheng, Keith

    2016-03-01

    Our group is developing a method to examine biological specimens in cellular detail using synchrotron microCT. The method can acquire 3D images of tissue at micrometer-scale resolutions, allowing for individual cell types to be visualized in the context of the entire specimen. For model organism research, this tool will enable the rapid characterization of tissue architecture and cellular morphology from every organ system. This characterization is critical for proposed and ongoing "phenome" projects that aim to phenotype whole-organism mutants and diseased tissues from different organisms including humans. With the envisioned collection of hundreds to thousands of images for a phenome project, it is important to develop quantitative image analysis tools for the automated scoring of organism phenotypes across organ systems. Here we present a first step towards that goal, demonstrating the use of support vector machines (SVM) in detecting retinal cell nuclei in 3D images of wild-type zebrafish. In addition, we apply the SVM classifier on a mutant zebrafish to examine whether SVMs can be used to capture phenotypic differences in these images. The longterm goal of this work is to allow cellular and tissue morphology to be characterized quantitatively for many organ systems, at the level of the whole-organism.

  19. Registration of 2D C-Arm and 3D CT Images for a C-Arm Image-Assisted Navigation System for Spinal Surgery

    Directory of Open Access Journals (Sweden)

    Chih-Ju Chang

    2015-01-01

    Full Text Available C-Arm image-assisted surgical navigation system has been broadly applied to spinal surgery. However, accurate path planning on the C-Arm AP-view image is difficult. This research studies 2D-3D image registration methods to obtain the optimum transformation matrix between C-Arm and CT image frames. Through the transformation matrix, the surgical path planned on preoperative CT images can be transformed and displayed on the C-Arm images for surgical guidance. The positions of surgical instruments will also be displayed on both CT and C-Arm in the real time. Five similarity measure methods of 2D-3D image registration including Normalized Cross-Correlation, Gradient Correlation, Pattern Intensity, Gradient Difference Correlation, and Mutual Information combined with three optimization methods including Powell’s method, Downhill simplex algorithm, and genetic algorithm are applied to evaluate their performance in converge range, efficiency, and accuracy. Experimental results show that the combination of Normalized Cross-Correlation measure method with Downhill simplex algorithm obtains maximum correlation and similarity in C-Arm and Digital Reconstructed Radiograph (DRR images. Spine saw bones are used in the experiment to evaluate 2D-3D image registration accuracy. The average error in displacement is 0.22 mm. The success rate is approximately 90% and average registration time takes 16 seconds.

  20. 3D active shape modeling for cardiac MR and CT image segmentation

    NARCIS (Netherlands)

    Assen, Hans Christiaan van

    2006-01-01

    3D Active Shape Modeling is a technique to capture shape information from a training set containing characteristic shapes of, e.g., a heart. The description contains a mean shape, and shape variations (e.g. eigen deformations and eigen values). Many models based on these statistics, and used for med

  1. A new efficient 2D combined with 3D CAD system for solitary pulmonary nodule detection in CT images

    Directory of Open Access Journals (Sweden)

    Xing Li

    2011-06-01

    Full Text Available Lung cancer has become one of the leading causes of death in the world. Clear evidence shows that early discovery, early diagnosis and early treatment of lung cancer can significantly increase the chance of survival for patients. Lung Computer-Aided Diagnosis (CAD is a potential method to accomplish a range of quantitative tasks such as early cancer and disease detection. Many computer-aided diagnosis (CAD methods, including 2D and 3D approaches, have been proposed for solitary pulmonary nodules (SPNs. However, the detection and diagnosis of SPNs remain challenging in many clinical circumstances. One goal of this work is to develop a two-stage approach that combines the simplicity of 2D and the accuracy of 3D methods. The experimental results show statistically significant differences between the diagnostic accuracy of 2D and 3Dmethods. The results also show that with a very minor drop in diagnostic performance the two-stage approach can significantly reduce the number of nodules needed to be processed by the 3D method, streamlining the computational demand. Finally, all malignant nodules were detected and a very low false-positive detection rate was achieved. The automated extraction of the lung in CT images is the most crucial step in a computer-aided diagnosis (CAD system. In this paper we describe a method, consisting of appropriate techniques, for the automated identification of the pulmonary volume. The performance is evaluated as a fully automated computerized method for the detection of lung nodules in computed tomography (CT scans in the identification of lung cancers that may be missed during visual interpretation.

  2. Iterative Mesh Transformation for 3D Segmentation of Livers with Cancers in CT Images

    OpenAIRE

    Lu, Difei; Wu, Yin; Harris, Gordon; Cai, Wenli

    2015-01-01

    Segmentation of diseased liver remains a challenging task in clinical applications due to the high inter-patient variability in liver shapes, sizes and pathologies caused by cancers or other liver diseases. In this paper, we present a multi-resolution mesh segmentation algorithm for 3D segmentation of livers, called iterative mesh transformation that deforms the mesh of a region-of-interest (ROI) in a progressive manner by iterations between mesh transformation and contour optimization. Mesh ...

  3. Three-dimensional image technology in forensic anthropology: Assessing the validity of biological profiles derived from CT-3D images of the skeleton

    Science.gov (United States)

    Garcia de Leon Valenzuela, Maria Julia

    This project explores the reliability of building a biological profile for an unknown individual based on three-dimensional (3D) images of the individual's skeleton. 3D imaging technology has been widely researched for medical and engineering applications, and it is increasingly being used as a tool for anthropological inquiry. While the question of whether a biological profile can be derived from 3D images of a skeleton with the same accuracy as achieved when using dry bones has been explored, bigger sample sizes, a standardized scanning protocol and more interobserver error data are needed before 3D methods can become widely and confidently used in forensic anthropology. 3D images of Computed Tomography (CT) scans were obtained from 130 innominate bones from Boston University's skeletal collection (School of Medicine). For each bone, both 3D images and original bones were assessed using the Phenice and Suchey-Brooks methods. Statistical analysis was used to determine the agreement between 3D image assessment versus traditional assessment. A pool of six individuals with varying experience in the field of forensic anthropology scored a subsample (n = 20) to explore interobserver error. While a high agreement was found for age and sex estimation for specimens scored by the author, the interobserver study shows that observers found it difficult to apply standard methods to 3D images. Higher levels of experience did not result in higher agreement between observers, as would be expected. Thus, a need for training in 3D visualization before applying anthropological methods to 3D bones is suggested. Future research should explore interobserver error using a larger sample size in order to test the hypothesis that training in 3D visualization will result in a higher agreement between scores. The need for the development of a standard scanning protocol focusing on the optimization of 3D image resolution is highlighted. Applications for this research include the possibility

  4. Contrast Enhancement Method Based on Gray and Its Distance Double-Weighting Histogram Equalization for 3D CT Images of PCBs

    Directory of Open Access Journals (Sweden)

    Lei Zeng

    2016-01-01

    Full Text Available Cone beam computed tomography (CBCT is a new detection method for 3D nondestructive testing of printed circuit boards (PCBs. However, the obtained 3D image of PCBs exhibits low contrast because of several factors, such as the occurrence of metal artifacts and beam hardening, during the process of CBCT imaging. Histogram equalization (HE algorithms cannot effectively extend the gray difference between a substrate and a metal in 3D CT images of PCBs, and the reinforcing effects are insignificant. To address this shortcoming, this study proposes an image enhancement algorithm based on gray and its distance double-weighting HE. Considering the characteristics of 3D CT images of PCBs, the proposed algorithm uses gray and its distance double-weighting strategy to change the form of the original image histogram distribution, suppresses the grayscale of a nonmetallic substrate, and expands the grayscale of wires and other metals. The proposed algorithm also enhances the gray difference between a substrate and a metal and highlights metallic materials. The proposed algorithm can enhance the gray value of wires and other metals in 3D CT images of PCBs. It applies enhancement strategies of changing gray and its distance double-weighting mechanism to adapt to this particular purpose. The flexibility and advantages of the proposed algorithm are confirmed by analyses and experimental results.

  5. 上颈椎不稳的3 D-CT等影像学和临床表现%The 3D-CT imaging and clinical symptoms of the upper cervical instability

    Institute of Scientific and Technical Information of China (English)

    范恒华; 王超; 杜俊杰; 刘冬州; 张洋; 侯中会

    2016-01-01

    目的:为了提高对上颈椎不稳的认识和重视,系统观察该疾病的3 D-CT影像学和临床表现。方法收集诊治的上颈椎不稳患者62例,采用CT(3D-CT、CTA)、X片等进行检查,结合临床表现,按轴性、前后、旋转不稳3种情况分别展示、描述,并对其进行总结分析和治疗。结果采用3D-CT技术,可以很好的发现和显示上颈椎不稳的原因及解剖结构异常,MRI能发现脊髓、脑干受压畸形等情况。通过对该病的影像学资料总结阅读、能够及时发现,避免漏诊,为及时治疗提供依据。结论采用X片、CT(3D-CT),可以有效发现上颈椎不稳,及时诊断。%Objective In order to pay more attention to upper cervical instability , the imaging of 3D-CT( three dimensional computed tomography and reconstructions ) and clinical symptoms of the upper cervical instability were systematically observed . Methods 62 cases of the upper cervical instability were studied on the diagnosis and treatment using 3D-CT, X films and com-bined with clinical symptoms .The 3D-CT imagings of 3 states, according to axial instability , instability in flexion and extension , rotation instability, were shown and described.Results The 3D-CT technology was a good tool to find and display the causes and anatomical structural abnormalities of upper cervical instability .We could detect and diagnosis the upper cervical instability through the 3D-CT imaging data, and could avoid misdiagnosis , provide the basis for timely treatment .Conclusion The upper cervical spine instability can effectively detect and timely diagnosis by 3D-CT, X-ray.

  6. Sectional depiction of the pelvic floor by CT, MR imaging and sheet plastination: computer-aided correlation and 3D model

    Energy Technology Data Exchange (ETDEWEB)

    Beyersdorff, D.; Taupitz, M.; Hamm, B. [Dept. of Radiology, Humboldt Univ., Berlin (Germany); Schiemann, T. [Inst. for Mathematics and Computer Science in Medicine, University of Hamburg (Germany); Kooijman, H. [Philips Medical Systems, Hamburg (Germany); Nicolas, V. [Dept. of Radiology and Nuclear Medicine, BG Kliniken Bergmannsheil, Bochum (Germany)

    2001-04-01

    The structures of the pelvic floor are clinically important but difficult to assess. To facilitate the understanding of the complicated pelvic floor anatomy on sectional images obtained by CT and MR imaging, and to make the representation more vivid, a computer-aided 3D model was created from a male and a female torso to develop a teaching tool. A male and a female cadaver torso were investigated by means of CT, MR imaging, and serial-section sheet plastination. A 3D reconstruction of the pelvic floor and adjacent structures was performed by fusion of CT and MR imaging data sets with sheet plastination sections. Corresponding sections from all three methods could be compared and visualized in their 3D context. Sheet plastination allows distinction of connective tissue, muscles, and pelvic organs down to a microscopic level. In combination with CT, MR imaging, and sheet plastination a 3D model of the pelvic floor offers a better understanding of the complex pelvic anatomy. This knowledge may be applied in the diagnostic imaging of urinary incontinence or prolapse and prior to prostate surgery. (orig.)

  7. Automatic localization of target vertebrae in spine surgery using fast CT-to-fluoroscopy (3D-2D) image registration

    Science.gov (United States)

    Otake, Y.; Schafer, S.; Stayman, J. W.; Zbijewski, W.; Kleinszig, G.; Graumann, R.; Khanna, A. J.; Siewerdsen, J. H.

    2012-02-01

    Localization of target vertebrae is an essential step in minimally invasive spine surgery, with conventional methods relying on "level counting" - i.e., manual counting of vertebrae under fluoroscopy starting from readily identifiable anatomy (e.g., the sacrum). The approach requires an undesirable level of radiation, time, and is prone to counting errors due to the similar appearance of vertebrae in projection images; wrong-level surgery occurs in 1 of every ~3000 cases. This paper proposes a method to automatically localize target vertebrae in x-ray projections using 3D-2D registration between preoperative CT (in which vertebrae are preoperatively labeled) and intraoperative fluoroscopy. The registration uses an intensity-based approach with a gradient-based similarity metric and the CMA-ES algorithm for optimization. Digitally reconstructed radiographs (DRRs) and a robust similarity metric are computed on GPU to accelerate the process. Evaluation in clinical CT data included 5,000 PA and LAT projections randomly perturbed to simulate human variability in setup of mobile intraoperative C-arm. The method demonstrated 100% success for PA view (projection error: 0.42mm) and 99.8% success for LAT view (projection error: 0.37mm). Initial implementation on GPU provided automatic target localization within about 3 sec, with further improvement underway via multi-GPU. The ability to automatically label vertebrae in fluoroscopy promises to streamline surgical workflow, improve patient safety, and reduce wrong-site surgeries, especially in large patients for whom manual methods are time consuming and error prone.

  8. A novel 3D graph cut based co-segmentation of lung tumor on PET-CT images with Gaussian mixture models

    Science.gov (United States)

    Yu, Kai; Chen, Xinjian; Shi, Fei; Zhu, Weifang; Zhang, Bin; Xiang, Dehui

    2016-03-01

    Positron Emission Tomography (PET) and Computed Tomography (CT) have been widely used in clinical practice for radiation therapy. Most existing methods only used one image modality, either PET or CT, which suffers from the low spatial resolution in PET or low contrast in CT. In this paper, a novel 3D graph cut method is proposed, which integrated Gaussian Mixture Models (GMMs) into the graph cut method. We also employed the random walk method as an initialization step to provide object seeds for the improvement of the graph cut based segmentation on PET and CT images. The constructed graph consists of two sub-graphs and a special link between the sub-graphs which penalize the difference segmentation between the two modalities. Finally, the segmentation problem is solved by the max-flow/min-cut method. The proposed method was tested on 20 patients' PET-CT images, and the experimental results demonstrated the accuracy and efficiency of the proposed algorithm.

  9. Automatic registration between 3D intra-operative ultrasound and pre-operative CT images of the liver based on robust edge matching

    Science.gov (United States)

    Nam, Woo Hyun; Kang, Dong-Goo; Lee, Duhgoon; Lee, Jae Young; Ra, Jong Beom

    2012-01-01

    The registration of a three-dimensional (3D) ultrasound (US) image with a computed tomography (CT) or magnetic resonance image is beneficial in various clinical applications such as diagnosis and image-guided intervention of the liver. However, conventional methods usually require a time-consuming and inconvenient manual process for pre-alignment, and the success of this process strongly depends on the proper selection of initial transformation parameters. In this paper, we present an automatic feature-based affine registration procedure of 3D intra-operative US and pre-operative CT images of the liver. In the registration procedure, we first segment vessel lumens and the liver surface from a 3D B-mode US image. We then automatically estimate an initial registration transformation by using the proposed edge matching algorithm. The algorithm finds the most likely correspondences between the vessel centerlines of both images in a non-iterative manner based on a modified Viterbi algorithm. Finally, the registration is iteratively refined on the basis of the global affine transformation by jointly using the vessel and liver surface information. The proposed registration algorithm is validated on synthesized datasets and 20 clinical datasets, through both qualitative and quantitative evaluations. Experimental results show that automatic registration can be successfully achieved between 3D B-mode US and CT images even with a large initial misalignment.

  10. Fusion of cone-beam CT and 3D photographic images for soft tissue simulation in maxillofacial surgery

    Science.gov (United States)

    Chung, Soyoung; Kim, Joojin; Hong, Helen

    2016-03-01

    During maxillofacial surgery, prediction of the facial outcome after surgery is main concern for both surgeons and patients. However, registration of the facial CBCT images and 3D photographic images has some difficulties that regions around the eyes and mouth are affected by facial expressions or the registration speed is low due to their dense clouds of points on surfaces. Therefore, we propose a framework for the fusion of facial CBCT images and 3D photos with skin segmentation and two-stage surface registration. Our method is composed of three major steps. First, to obtain a CBCT skin surface for the registration with 3D photographic surface, skin is automatically segmented from CBCT images and the skin surface is generated by surface modeling. Second, to roughly align the scale and the orientation of the CBCT skin surface and 3D photographic surface, point-based registration with four corresponding landmarks which are located around the mouth is performed. Finally, to merge the CBCT skin surface and 3D photographic surface, Gaussian-weight-based surface registration is performed within narrow-band of 3D photographic surface.

  11. Morphometric measurement of the patella on 3D model reconstructed from CT scan images for the southern Chinese population

    Institute of Scientific and Technical Information of China (English)

    Shang Peng; Zhang Linan; Hou Zengtao; Bai Xueling; Ye Xin; Xu Zhaobin; Huang Xu

    2014-01-01

    Background Due to racial differences in the morphology of the knee joint and due to most prostheses available in the market being designed using measurements from Caucasians,the objective of this study was to provide the morphometric data of the patella for the southern Chinese population for total knee arthroplasty (TKA),patellar resurfacing,and prostheses design.Methods The CT slices of the knee joint were obtained from both knees of 40 Chinese volunteers (20 females,20 males,and age from 20-25 years) by performing a computer tomographic scan.A 3D model was reconstructed by Mimics software based on the computed tomography images.Six metrical characteristics were measured by digital ruler.Statistical analysis was performed with the SPSS statistical program.Results The mean,standard deviation and P values of measurements and ratios were calculated using SPSS.All dimensions showed a significant gender difference with P<0.05,but the six variables of the left and right knees had no statistical significance with P>0.05.In addition,we studied the relationship between six couples (H-W,H-T,H-HAF,W-T,W-HAF,T-HAF) of the four variables (H:height,W:width,T:thickness and HAF:height of articulating facet) that were measured,which showed a significant correlation.Conclusions Examination of the southern Chinese population revealed that males have larger patellae than women.In both genders,comparing data between left and right knees shows no statistically significant difference.Compared with Westerners in previous studies,the patella in our study was thin and small.There was a good linear regression correlation between measurements of the patella.The indirect measurement method on 3D models makes it easy to obtain anatomical data,and the results can provide a region and gender specific database for morphometric measurements of the oatella,and can be helpful for designing implants suited for southern Chinese patients.

  12. Application of CT 3D reconstruction in diagnosing atlantoaxial subluxation

    Institute of Scientific and Technical Information of China (English)

    段少银; 林清池; 庞瑞麟

    2004-01-01

    Objective:To evaluate and compare the diagnostic value in atlantoaxial subluxation by CT three-dimensional (3D) reconstruction.Methods:3D reconstruction fimdings of 41 patients with atlantoaxiai subluxation were retrospectively analyzed, and comparisons were made among images of transverse section, multiplanar reformorting (MPR), surface shade display (SSD), maximum intensity project (MIP), and volume rendering (VR). Results:Of 41 patients with atlantoaxial subluxation, 31 belonged to rotary dislocation, 5 antedislocation, and 5 hind dislocation. All the cases showed the dislocated joint panel of atlantoaxial articulation.Fifteen cases showed deviation of the odontoid process and 8 cases widened distance between the dens and anterior arch of the atlas. The dislocated joint panel of atlantoaxial articulation was more clearly seen with SSD-3D imaging than any other methods. Conclusions:Atlantoaxial subluxation can well be diagnosed by CT 3D reconstruction, in which SSD-3D imaging is optimal.

  13. The effect of spatial micro-CT image resolution and surface complexity on the morphological 3D analysis of open porous structures

    Energy Technology Data Exchange (ETDEWEB)

    Pyka, Grzegorz, E-mail: gregory.pyka@mtm.kuleuven.be [Department of Metallurgy and Materials Engineering, KU Leuven, Kasteelpark Arenberg 44 – PB2450, B-3001 Leuven (Belgium); Kerckhofs, Greet [Department of Metallurgy and Materials Engineering, KU Leuven, Kasteelpark Arenberg 44 – PB2450, B-3001 Leuven (Belgium); Biomechanics Research Unit, Université de Liege, Chemin des Chevreuils 1 - BAT 52/3, B-4000 Liège (Belgium); Schrooten, Jan; Wevers, Martine [Department of Metallurgy and Materials Engineering, KU Leuven, Kasteelpark Arenberg 44 – PB2450, B-3001 Leuven (Belgium)

    2014-01-15

    In material science microfocus X-ray computed tomography (micro-CT) is one of the most popular non-destructive techniques to visualise and quantify the internal structure of materials in 3D. Despite constant system improvements, state-of-the-art micro-CT images can still hold several artefacts typical for X-ray CT imaging that hinder further image-based processing, structural and quantitative analysis. For example spatial resolution is crucial for an appropriate characterisation as the voxel size essentially influences the partial volume effect. However, defining the adequate image resolution is not a trivial aspect and understanding the correlation between scan parameters like voxel size and the structural properties is crucial for comprehensive material characterisation using micro-CT. Therefore, the objective of this study was to evaluate the influence of the spatial image resolution on the micro-CT based morphological analysis of three-dimensional (3D) open porous structures with a high surface complexity. In particular the correlation between the local surface properties and the accuracy of the micro-CT-based macro-morphology of 3D open porous Ti6Al4V structures produced by selective laser melting (SLM) was targeted and revealed for rough surfaces a strong dependence of the resulting structure characteristics on the scan resolution. Reducing the surface complexity by chemical etching decreased the sensitivity of the overall morphological analysis to the spatial image resolution and increased the detection limit. This study showed that scan settings and image processing parameters need to be customized to the material properties, morphological parameters under investigation and the desired final characteristics (in relation to the intended functional use). Customization of the scan resolution can increase the reliability of the micro-CT based analysis and at the same time reduce its operating costs. - Highlights: • We examine influence of the image resolution

  14. SU-C-201-06: Utility of Quantitative 3D SPECT/CT Imaging in Patient Specific Internal Dosimetry of 153-Samarium with GATE Monte Carlo Package

    Energy Technology Data Exchange (ETDEWEB)

    Fallahpoor, M; Abbasi, M [Tehran University of Medical Sciences, Vali-Asr Hospital, Tehran, Tehran (Iran, Islamic Republic of); Sen, A [University of Houston, Houston, TX (United States); Parach, A [Shahid Sadoughi University of Medical Sciences, Yazd, Yazd (Iran, Islamic Republic of); Kalantari, F [UT Southwestern Medical Center, Dallas, TX (United States)

    2015-06-15

    Purpose: Patient-specific 3-dimensional (3D) internal dosimetry in targeted radionuclide therapy is essential for efficient treatment. Two major steps to achieve reliable results are: 1) generating quantitative 3D images of radionuclide distribution and attenuation coefficients and 2) using a reliable method for dose calculation based on activity and attenuation map. In this research, internal dosimetry for 153-Samarium (153-Sm) was done by SPECT-CT images coupled GATE Monte Carlo package for internal dosimetry. Methods: A 50 years old woman with bone metastases from breast cancer was prescribed 153-Sm treatment (Gamma: 103keV and beta: 0.81MeV). A SPECT/CT scan was performed with the Siemens Simbia-T scanner. SPECT and CT images were registered using default registration software. SPECT quantification was achieved by compensating for all image degrading factors including body attenuation, Compton scattering and collimator-detector response (CDR). Triple energy window method was used to estimate and eliminate the scattered photons. Iterative ordered-subsets expectation maximization (OSEM) with correction for attenuation and distance-dependent CDR was used for image reconstruction. Bilinear energy mapping is used to convert Hounsfield units in CT image to attenuation map. Organ borders were defined by the itk-SNAP toolkit segmentation on CT image. GATE was then used for internal dose calculation. The Specific Absorbed Fractions (SAFs) and S-values were reported as MIRD schema. Results: The results showed that the largest SAFs and S-values are in osseous organs as expected. S-value for lung is the highest after spine that can be important in 153-Sm therapy. Conclusion: We presented the utility of SPECT-CT images and Monte Carlo for patient-specific dosimetry as a reliable and accurate method. It has several advantages over template-based methods or simplified dose estimation methods. With advent of high speed computers, Monte Carlo can be used for treatment planning

  15. Correlative 3D-imaging of Pipistrellus penis micromorphology: Validating quantitative microCT images with undecalcified serial ground section histomorphology.

    Science.gov (United States)

    Herdina, Anna Nele; Plenk, Hanns; Benda, Petr; Lina, Peter H C; Herzig-Straschil, Barbara; Hilgers, Helge; Metscher, Brian D

    2015-06-01

    Detailed knowledge of histomorphology is a prerequisite for the understanding of function, variation, and development. In bats, as in other mammals, penis and baculum morphology are important in species discrimination and phylogenetic studies. In this study, nondestructive 3D-microtomographic (microCT, µCT) images of bacula and iodine-stained penes of Pipistrellus pipistrellus were correlated with light microscopic images from undecalcified surface-stained ground sections of three of these penes of P. pipistrellus (1 juvenile). The results were then compared with µCT-images of bacula of P. pygmaeus, P. hanaki, and P. nathusii. The Y-shaped baculum in all studied Pipistrellus species has a proximal base with two club-shaped branches, a long slender shaft, and a forked distal tip. The branches contain a medullary cavity of variable size, which tapers into a central canal of variable length in the proximal baculum shaft. Both are surrounded by a lamellar and a woven bone layer and contain fatty marrow and blood vessels. The distal shaft consists of woven bone only, without a vascular canal. The proximal ends of the branches are connected with the tunica albuginea of the corpora cavernosa via entheses. In the penis shaft, the corpus spongiosum-surrounded urethra lies in a ventral grove of the corpora cavernosa, and continues in the glans under the baculum. The glans penis predominantly comprises an enlarged corpus spongiosum, which surrounds urethra and baculum. In the 12 studied juvenile and subadult P. pipistrellus specimens the proximal branches of the baculum were shorter and without marrow cavity, while shaft and distal tip appeared already fully developed. The present combination with light microscopic images from one species enabled a more reliable interpretation of histomorphological structures in the µCT-images from all four Pipistrellus species.

  16. Evaluation of the combined effects of target size, respiratory motion and background activity on 3D and 4D PET/CT images

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang-June; Ionascu, Dan; Killoran, Joseph; Chin, Lee; Berbeco, Ross [Department of Radiation Oncology, Brigham and Women' s Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115 (United States); Mamede, Marcelo; Gerbaudo, Victor H [Division of Nuclear Medicine, Department of Radiology, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA 02115 (United States)], E-mail: spark@lroc.harvard.edu

    2008-07-07

    Gated (4D) PET/CT has the potential to greatly improve the accuracy of radiotherapy at treatment sites where internal organ motion is significant. However, the best methodology for applying 4D-PET/CT to target definition is not currently well established. With the goal of better understanding how to best apply 4D information to radiotherapy, initial studies were performed to investigate the effect of target size, respiratory motion and target-to-background activity concentration ratio (TBR) on 3D (ungated) and 4D PET images. Using a PET/CT scanner with 4D or gating capability, a full 3D-PET scan corrected with a 3D attenuation map from 3D-CT scan and a respiratory gated (4D) PET scan corrected with corresponding attenuation maps from 4D-CT were performed by imaging spherical targets (0.5-26.5 mL) filled with {sup 18}F-FDG in a dynamic thorax phantom and NEMA IEC body phantom at different TBRs (infinite, 8 and 4). To simulate respiratory motion, the phantoms were driven sinusoidally in the superior-inferior direction with amplitudes of 0, 1 and 2 cm and a period of 4.5 s. Recovery coefficients were determined on PET images. In addition, gating methods using different numbers of gating bins (1-20 bins) were evaluated with image noise and temporal resolution. For evaluation, volume recovery coefficient, signal-to-noise ratio and contrast-to-noise ratio were calculated as a function of the number of gating bins. Moreover, the optimum thresholds which give accurate moving target volumes were obtained for 3D and 4D images. The partial volume effect and signal loss in the 3D-PET images due to the limited PET resolution and the respiratory motion, respectively were measured. The results show that signal loss depends on both the amplitude and pattern of respiratory motion. However, the 4D-PET successfully recovers most of the loss induced by the respiratory motion. The 5-bin gating method gives the best temporal resolution with acceptable image noise. The results based on

  17. An Optimized Spline-Based Registration of a 3D CT to a Set of C-Arm Images.

    Science.gov (United States)

    Jonić, S; Thévenaz, P; Zheng, G; Nolte, L-P; Unser, M

    2006-01-01

    We have developed an algorithm for the rigid-body registration of a CT volume to a set of C-arm images. The algorithm uses a gradient-based iterative minimization of a least-squares measure of dissimilarity between the C-arm images and projections of the CT volume. To compute projections, we use a novel method for fast integration of the volume along rays. To improve robustness and speed, we take advantage of a coarse-to-fine processing of the volume/image pyramids. To compute the projections of the volume, the gradient of the dissimilarity measure, and the multiresolution data pyramids, we use a continuous image/volume model based on cubic B-splines, which ensures a high interpolation accuracy and a gradient of the dissimilarity measure that is well defined everywhere. We show the performance of our algorithm on a human spine phantom, where the true alignment is determined using a set of fiducial markers.

  18. Detecting Radiation-Induced Injury Using Rapid 3D Variogram Analysis of CT Images of Rat Lungs

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, Rick E.; Murphy, Mark K.; Creim, Jeffrey A.; Carson, James P.

    2013-10-01

    A new heterogeneity analysis approach to discern radiation-induced lung damage was tested on CT images of irradiated rats. The method, combining octree decomposition with variogram analysis, demonstrated a significant correlation with radiation exposure levels, whereas conventional measurements and pulmonary function tests did not. The results suggest the new approach may be highly sensitive for assessing even subtle radiation-induced changes

  19. High-quality 3D correction of ring and radiant artifacts in flat panel detector-based cone beam volume CT imaging.

    Science.gov (United States)

    Anas, Emran Mohammad Abu; Kim, Jae Gon; Lee, Soo Yeol; Hasan, Md Kamrul

    2011-10-07

    The use of an x-ray flat panel detector is increasingly becoming popular in 3D cone beam volume CT machines. Due to the deficient semiconductor array manufacturing process, the cone beam projection data are often corrupted by different types of abnormalities, which cause severe ring and radiant artifacts in a cone beam reconstruction image, and as a result, the diagnostic image quality is degraded. In this paper, a novel technique is presented for the correction of error in the 2D cone beam projections due to abnormalities often observed in 2D x-ray flat panel detectors. Template images are derived from the responses of the detector pixels using their statistical properties and then an effective non-causal derivative-based detection algorithm in 2D space is presented for the detection of defective and mis-calibrated detector elements separately. An image inpainting-based 3D correction scheme is proposed for the estimation of responses of defective detector elements, and the responses of the mis-calibrated detector elements are corrected using the normalization technique. For real-time implementation, a simplification of the proposed off-line method is also suggested. Finally, the proposed algorithms are tested using different real cone beam volume CT images and the experimental results demonstrate that the proposed methods can effectively remove ring and radiant artifacts from cone beam volume CT images compared to other reported techniques in the literature.

  20. Intensity-Based Registration of Freehand 3D Ultrasound and CT-scan Images of the Kidney

    CERN Document Server

    Leroy, Antoine; Payan, Yohan; Troccaz, Jocelyne

    2007-01-01

    This paper presents a method to register a pre-operative Computed-Tomography (CT) volume to a sparse set of intra-operative Ultra-Sound (US) slices. In the context of percutaneous renal puncture, the aim is to transfer planning information to an intra-operative coordinate system. The spatial position of the US slices is measured by optically localizing a calibrated probe. Assuming the reproducibility of kidney motion during breathing, and no deformation of the organ, the method consists in optimizing a rigid 6 Degree Of Freedom (DOF) transform by evaluating at each step the similarity between the set of US images and the CT volume. The correlation between CT and US images being naturally rather poor, the images have been preprocessed in order to increase their similarity. Among the similarity measures formerly studied in the context of medical image registration, Correlation Ratio (CR) turned out to be one of the most accurate and appropriate, particularly with the chosen non-derivative minimization scheme, n...

  1. Prenatal diagnosis of fetal skeletal dysplasia with 3D CT

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Osamu; Horiuchi, Tetsuya [National Center for Child Health and Development, Department of Radiology, Seatagaya-ku, Tokyo (Japan); Nishimura, Gen [Tokyo Metropolitan Children' s Medical Center, Department of Pediatric Imaging, Fuchu-shi, Tokyo (Japan); Sago, Haruhiko; Hayashi, Satoshi [National Center for Child Health and Development, Department of Perinatal Medicine and Maternal Care, Seatagaya-ku, Tokyo (Japan); Kosaki, Rika [National Center for Child Health and Development, Department of Strategic Medicine, Division of Clinical Genetics and Molecular Medicine, Seatagaya-ku, Tokyo (Japan)

    2012-07-15

    Clinical use of 3D CT for fetal skeletal malformations is controversial. The purpose of this study was to evaluate the efficacy of fetal 3D CT using three protocols with different radiation doses and through comparing findings between fetal CT and conventional postnatal radiographic skeletal survey. Seventeen fetuses underwent CT for suspected skeletal dysplasia. A relay of three CT protocols with stepwise dose-reduction were used over the study period. The concordance between the CT diagnosis and the final diagnosis was assessed. Ninety-three radiological findings identifiable on radiographs were compared with CT. Fetal CT provided the correct diagnosis in all 17 fetuses, the detectability rate of cardinal findings was 93.5 %. In 59 % of the fetuses an US-based diagnosis was changed prenatally due to CT findings. The estimated fetal radiation dose in the final protocol was 3.4 mSv (50 %) of the initial protocol, and this dose reduction did not result in degraded image quality. The capability of fetal CT to delineate the skeleton was almost the same as that of postnatal skeletal survey. The perinatal management was altered due to these more specific CT findings, which aided in counseling and in the management of the pregnancy. (orig.)

  2. Advanced 3-D Ultrasound Imaging

    DEFF Research Database (Denmark)

    Rasmussen, Morten Fischer

    The main purpose of the PhD project was to develop methods that increase the 3-D ultrasound imaging quality available for the medical personnel in the clinic. Acquiring a 3-D volume gives the medical doctor the freedom to investigate the measured anatomy in any slice desirable after the scan has...... been completed. This allows for precise measurements of organs dimensions and makes the scan more operator independent. Real-time 3-D ultrasound imaging is still not as widespread in use in the clinics as 2-D imaging. A limiting factor has traditionally been the low image quality achievable using...... Field II simulations and measurements with the ultrasound research scanner SARUS and a 3.5MHz 1024 element 2-D transducer array. In all investigations, 3-D synthetic aperture imaging achieved a smaller main-lobe, lower sidelobes, higher contrast, and better signal to noise ratio than parallel...

  3. SU-E-T-296: Dosimetric Analysis of Small Animal Image-Guided Irradiator Using High Resolution Optical CT Imaging of 3D Dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Na, Y; Qian, X; Wuu, C [Columbia University, New York, NY (United States); Adamovics, J [John Adamovics, Skillman, NJ (United States)

    2015-06-15

    Purpose: To verify the dosimetric characteristics of a small animal image-guided irradiator using a high-resolution of optical CT imaging of 3D dosimeters. Methods: PRESAEGE 3D dosimeters were used to determine dosimetric characteristics of a small animal image-guided irradiator and compared with EBT2 films. Cylindrical PRESAGE dosimeters with 7cm height and 6cm diameter were placed along the central axis of the beam. The films were positioned between 6×6cm{sup 2} cubed plastic water phantoms perpendicular to the beam direction with multiple depths. PRESAGE dosimeters and EBT2 films were then irradiated with the irradiator beams at 220kVp and 13mA. Each of irradiated PRESAGE dosimeters named PA1, PA2, PB1, and PB2, was independently scanned using a high-resolution single laser beam optical CT scanner. The transverse images were reconstructed with a 0.1mm high-resolution pixel. A commercial Epson Expression 10000XL flatbed scanner was used for readout of irradiated EBT2 films at a 0.4mm pixel resolution. PDD curves and beam profiles were measured for the irradiated PRESAGE dosimeters and EBT2 films. Results: The PDD agreements between the irradiated PRESAGE dosimeter PA1, PA2, PB1, PB2 and the EB2 films were 1.7, 2.3, 1.9, and 1.9% for the multiple depths at 1, 5, 10, 15, 20, 30, 40 and 50mm, respectively. The FWHM measurements for each PRESAEGE dosimeter and film agreed with 0.5, 1.1, 0.4, and 1.7%, respectively, at 30mm depth. Both PDD and FWHM measurements for the PRESAGE dosimeters and the films agreed overall within 2%. The 20%–80% penumbral widths of each PRESAGE dosimeter and the film at a given depth were respectively found to be 0.97, 0.91, 0.79, 0.88, and 0.37mm. Conclusion: Dosimetric characteristics of a small animal image-guided irradiator have been demonstrated with the measurements of PRESAGE dosimeter and EB2 film. With the high resolution and accuracy obtained from this 3D dosimetry system, precise targeting small animal irradiation can be

  4. Usefulness and problems of three-dimensional CT (3D-CT) in the neurosurgical patients

    Energy Technology Data Exchange (ETDEWEB)

    Terada, Kousaku; Tajitsu, Kenichiro; Ichitsubo, Hidenori [Kaseda Hospital, Kagoshima (Japan); Moriya, Nobuhide; Kadota, Koki; Asakura, Tetsuhiko

    1997-11-01

    Helical CT scanning is a new technique that can uninterruptedly generate a volume of data. The data thus acquired with or without contrast medium is reconstructed for three-dimensional CT (3D-CT) or three-dimensional CT angiography (3D-CTA). The authors have studied 36 aneurysms, 11 aterosclerotic lesions, 16 tumors and 14 traumatic lesions in more than 60 patients with 3D-CT or 3D-CTA. Aneurysm is visualized clearly on 3D-CTA. The ability to rotate images in all planes aids in showing the aneurysm neck and dome, parent artery and surrounding bony structures. 3D-CTA can assist the surgeon in the approach to the aneurysm. Imaging of the infraclinoid portion of the internal carotid artery may be inadequate with 3D-CTA because of contrast enhancement of the cavernous sinus and the anterior portion of the lesser sphenoid wing. Stenosis or occlusion of the circle of Willis and the common carotid artery bifurcation is well identified on 3D-CTA. It is noted that 3D-CTA delineates inaccurately stenosis severity because of partial volume effects, the threshold level and the timing of scanning. Well-enhanced brain tumors such as meningioma are demonstrated clearly. The relationship of the tumor to surrounding major arteries and bony structures is well defined on enhanced 3D-CT. Marked transposition of skull fracture by head trauma is shown distinctly on 3D-CT. In conclusion, although this technique requires further development and clinical evaluation, the authors` experience with 3D-CT and 3D-CTA suggests that this may become a valuable tool in the diagnosis of neurosurgical patients. (author)

  5. 3D Reconstruction in Spiral Multislice CT Scans

    Directory of Open Access Journals (Sweden)

    M. Ghafouri

    2005-08-01

    Full Text Available Introduction & Background: The rapid development of spiral (helical computed tomography (CT has resulted in exciting new applications for CT. One of these applications, three-dimensional (3D CT with volume ren-dering, is now a major area of clinical and academic interest. One of the greatest advantages of spiral CT with 3D volume rendering is that it provides all the necessary information in a single radiologic study (and there-fore at the lowest possible price in cases that previously required two or more studies. Three-dimensional vol-ume rendering generates clinically accurate and immediately available images from the full CT data set with-out extensive editing. It allows the radiologist and clinician to address specific questions concerning patient care by interactively exploring different aspects of the data set. Three-dimensional images integrate a series of axial CT sections into a form that is often easier to interpret than the sections themselves and can be made to appear similar to other more familiar images such as catheter angiograms. The data are organized into a 3D matrix of volume elements (voxels. The screen of the computer monitor is a 2D-surface composed of discrete picture elements (pixels. Presenting what is stored in memory (ie, floating within the monitor on a 2D-screen is a challenge, but it is the very problem that 3D reconstruc-tion software has creatively solved. Voxel selection is usually accomplished by projecting lines (rays through the data set that correspond to the pixel matrix of the desired 2D image. Differences in the images produced with various 3D rendering techniques are the result of variations in how voxels are selected and weighted. In this article, I compare 3D volume rendering of spiral CT data with other rendering techniques (shaded surface display, maximum intensity projection and present a brief history of 3D volume rendering and discuss the im-plementation of this promising technology in terms of

  6. An Optimized Spline-Based Registration of a 3D CT to a Set of C-Arm Images

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available We have developed an algorithm for the rigid-body registration of a CT volume to a set of C-arm images. The algorithm uses a gradient-based iterative minimization of a least-squares measure of dissimilarity between the C-arm images and projections of the CT volume. To compute projections, we use a novel method for fast integration of the volume along rays. To improve robustness and speed, we take advantage of a coarse-to-fine processing of the volume/image pyramids. To compute the projections of the volume, the gradient of the dissimilarity measure, and the multiresolution data pyramids, we use a continuous image/volume model based on cubic B-splines, which ensures a high interpolation accuracy and a gradient of the dissimilarity measure that is well defined everywhere. We show the performance of our algorithm on a human spine phantom, where the true alignment is determined using a set of fiducial markers.

  7. MTF characterization in 2D and 3D for a high resolution, large field of view flat panel imager for cone beam CT

    Science.gov (United States)

    Shah, Jainil; Mann, Steve D.; Tornai, Martin P.; Richmond, Michelle; Zentai, George

    2014-03-01

    The 2D and 3D modulation transfer functions (MTFs) of a custom made, large 40x30cm2 area, 600- micron CsI-TFT based flat panel imager having 127-micron pixellation, along with the micro-fiber scintillator structure, were characterized in detail using various techniques. The larger area detector yields a reconstructed FOV of 25cm diameter with an 80cm SID in CT mode. The MTFs were determined with 1x1 (intrinsic) binning. The 2D MTFs were determined using a 50.8 micron tungsten wire and a solid lead edge, and the 3D MTF was measured using a custom made phantom consisting of three nearly orthogonal 50.8 micron tungsten wires suspended in an acrylic cubic frame. The 2D projection data was reconstructed using an iterative OSC algorithm using 16 subsets and 5 iterations. As additional verification of the resolution, along with scatter, the Catphan® phantom was also imaged and reconstructed with identical parameters. The measured 2D MTF was ~4% using the wire technique and ~1% using the edge technique at the 3.94 lp/mm Nyquist cut-off frequency. The average 3D MTF measured along the wires was ~8% at the Nyquist. At 50% MTF, the resolutions were 1.2 and 2.1 lp/mm in 2D and 3D, respectively. In the Catphan® phantom, the 1.7 lp/mm bars were easily observed. Lastly, the 3D MTF measured on the three wires has an observed 5.9% RMSD, indicating that the resolution of the imaging system is uniform and spatially independent. This high performance detector is integrated into a dedicated breast SPECT-CT imaging system.

  8. 3D-CT angiography. Intracranial arterial lesions

    Energy Technology Data Exchange (ETDEWEB)

    Asato, Mikio; Tong, X.Q.; Tamura, Shozo [Miyazaki Medical Coll., Kiyotake (Japan)] [and others

    1997-06-01

    Since its introduction, three dimensional CT angiography (3D-CTA) on spiral (helical) CT has played an important role in clinical imaging. Initially it was reported to be useful in depicting aortic abnormalities, afterwards the merit in detecting intracranial aneurysm by 3D-CTA was also described. We have investigated the usefullness of 3D-CTA in detecting patients of intracranial aneurysm as well as arterio-venous malformation (AVM), Moyamoya disease and stenosis of middle cerebral artery, meanwhile the MR angiography (MRA) and digital subtraction angiography (DSA) examination of these patients were also studied as comparison to the 3D-CTA results. The sensitivity and specificity on investigating intracranial aneurysm were similar with other reports so far. 3D-CTA was possible to identify the feeding artery, nidus and draining vein of AVM, although DSA showed higher detectability. Occlusion of internal carotid artery and post-operative anastomosis in Moyamoya disease were all demonstrated by 3D-CTA, however the Moyamoya collaterals were shown better on MRA. 3D-CTA revealed the site of stenosis of middle cerebral artery in all of our cases, but in general maximum intensity projection (MIP) images can provide more exact information about the degree of stenosis. Five years has passed since the emergence of spiral CT and utilizing of 3D-CTA in clinical applications. With the development of hard and soft ware in the near future, it is possible to delineate more small vessels by 3D-CTA. We predict that 3D-CTA would be widely used for detecting vasculature of the whole body, and may take the place of conventional angiography in many cases. (author)

  9. Automatic Segmentation of Colon in 3D CT Images and Removal of Opacified Fluid Using Cascade Feed Forward Neural Network

    Directory of Open Access Journals (Sweden)

    K. Gayathri Devi

    2015-01-01

    Full Text Available Purpose. Colon segmentation is an essential step in the development of computer-aided diagnosis systems based on computed tomography (CT images. The requirement for the detection of the polyps which lie on the walls of the colon is much needed in the field of medical imaging for diagnosis of colorectal cancer. Methods. The proposed work is focused on designing an efficient automatic colon segmentation algorithm from abdominal slices consisting of colons, partial volume effect, bowels, and lungs. The challenge lies in determining the exact colon enhanced with partial volume effect of the slice. In this work, adaptive thresholding technique is proposed for the segmentation of air packets, machine learning based cascade feed forward neural network enhanced with boundary detection algorithms are used which differentiate the segments of the lung and the fluids which are sediment at the side wall of colon and by rejecting bowels based on the slice difference removal method. The proposed neural network method is trained with Bayesian regulation algorithm to determine the partial volume effect. Results. Experiment was conducted on CT database images which results in 98% accuracy and minimal error rate. Conclusions. The main contribution of this work is the exploitation of neural network algorithm for removal of opacified fluid to attain desired colon segmentation result.

  10. Diagnostic Importance of 3D CT Images in Klippel-Feil Syndrome with Multiple Skeletal Anomalies: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Yuksel, Murvet [Kahramanmaras Sutcu Imam University, Radiology Dept. (Turkey); Karabiber, Hamza [Kahramanmaras Sutcu Imam University Pediatrics Dept. (Turkey); Yuksel, K. Zafer [Kahramanmaras Sutcu Imam University Neuroradiology Dept (Turkey); Parmaksiz, Gonul [Kahramanmaras Sutcu Imam University Pediatrics Dept. (Turkey)

    2005-07-01

    We present here the case of a 12-year-old boy who had Klippel-Feil syndrome with renal, cardiac and multiple skeletal anomalies, and we show the relevent three-dimensional computed tomography images. Our patient had a triple renal pelvis, mitral valve prolapsus, multiple cervical vertebrae fusions, cervical ribs, hypoplasia of the right thumb, spina bifida of L5, lumbalization at the right side of S1 and a sacral curved defect. In this study, we discuss the atypical clinical features and the diagnostic value of three-dimensional CT for evaluating the skeletal anomalies of the Klippel-Feil syndrome cases.

  11. Quantification of the accuracy of MRI generated 3D models of long bones compared to CT generated 3D models.

    Science.gov (United States)

    Rathnayaka, Kanchana; Momot, Konstantin I; Noser, Hansrudi; Volp, Andrew; Schuetz, Michael A; Sahama, Tony; Schmutz, Beat

    2012-04-01

    Orthopaedic fracture fixation implants are increasingly being designed using accurate 3D models of long bones based on computer tomography (CT). Unlike CT, magnetic resonance imaging (MRI) does not involve ionising radiation and is therefore a desirable alternative to CT. This study aims to quantify the accuracy of MRI-based 3D models compared to CT-based 3D models of long bones. The femora of five intact cadaver ovine limbs were scanned using a 1.5 T MRI and a CT scanner. Image segmentation of CT and MRI data was performed using a multi-threshold segmentation method. Reference models were generated by digitising the bone surfaces free of soft tissue with a mechanical contact scanner. The MRI- and CT-derived models were validated against the reference models. The results demonstrated that the CT-based models contained an average error of 0.15 mm while the MRI-based models contained an average error of 0.23 mm. Statistical validation shows that there are no significant differences between 3D models based on CT and MRI data. These results indicate that the geometric accuracy of MRI based 3D models was comparable to that of CT-based models and therefore MRI is a potential alternative to CT for generation of 3D models with high geometric accuracy.

  12. Standard Splenic Volume Estimation in North Indian Adult Population: Using 3D Reconstruction of Abdominal CT Scan Images

    Directory of Open Access Journals (Sweden)

    Adil Asghar

    2011-01-01

    Full Text Available A prospective study was carried out to establish normative data for splenic dimensions in North Indian population and their correlation with physical standard on abdominal CT of 21 patients aged between 20 and 70 years having no splenic disorders. Splenic volume was measured by two methods—volume and surface rendering technique of Able 3D doctor software and prolate ellipsoid formula. Volumes measured by both the techniques were correlated with their physical standards. Mean splenic volume was 161.57±90.2 cm3 and range 45.7–271.46 cm3. The volume of spleen had linear correlation with body height (r=0.512, P<.05. Splenic volume (cm3 = 7 × height (cm − 961 can be used to generate normal standard volume of spleen as a function of body height in North Indian population (with 95% confidence interval. This formula can be used to objectively measure the size of the spleen in adults who have clinically suspected splenomegaly.

  13. A stochastic approach for automatic registration and fusion of left atrial electroanatomic maps with 3D CT anatomical images

    Energy Technology Data Exchange (ETDEWEB)

    Cristoforetti, Alessandro [Department of Physics, University of Trento, 38050 Povo-Trento (Italy); Mase, Michela [Department of Physics, University of Trento, 38050 Povo-Trento (Italy); Faes, Luca [Department of Physics, University of Trento, 38050 Povo-Trento (Italy); Centonze, Maurizio [Division of Radiology, S Chiara Hospital, 38100 Trento (Italy); Greco, Maurizio Del [Division of Cardiology, S Chiara Hospital, 38100 Trento (Italy); Antolini, Renzo [Department of Physics, University of Trento, 38050 Povo-Trento (Italy); Nollo, Giandomenico [Department of Physics, University of Trento, 38050 Povo-Trento (Italy); Ravelli, Flavia [Department of Physics, University of Trento, 38050 Povo-Trento (Italy)

    2007-10-21

    The integration of electroanatomic maps with highly resolved computed tomography cardiac images plays an important role in the successful planning of the ablation procedure of arrhythmias. In this paper, we present and validate a fully-automated strategy for the registration and fusion of sparse, atrial endocardial electroanatomic maps (CARTO maps) with detailed left atrial (LA) anatomical reconstructions segmented from a pre-procedural MDCT scan. Registration is accomplished by a parameterized geometric transformation of the CARTO points and by a stochastic search of the best parameter set which minimizes the misalignment between transformed CARTO points and the LA surface. The subsequent fusion of electrophysiological information on the registered CT atrium is obtained through radial basis function interpolation. The algorithm is validated by simulation and by real data from 14 patients referred to CT imaging prior to the ablation procedure. Results are presented, which show the validity of the algorithmic scheme as well as the accuracy and reproducibility of the integration process. The obtained results encourage the application of the integration method in post-intervention ablation assessment and basic AF research and suggest the development for real-time applications in catheter guiding during ablation intervention.

  14. Comparative evaluation of a novel 3D segmentation algorithm on in-treatment radiotherapy cone beam CT images

    Science.gov (United States)

    Price, Gareth; Moore, Chris

    2007-03-01

    Image segmentation and delineation is at the heart of modern radiotherapy, where the aim is to deliver as high a radiation dose as possible to a cancerous target whilst sparing the surrounding healthy tissues. This, of course, requires that a radiation oncologist dictates both where the tumour and any nearby critical organs are located. As well as in treatment planning, delineation is of vital importance in image guided radiotherapy (IGRT): organ motion studies demand that features across image databases are accurately segmented, whilst if on-line adaptive IGRT is to become a reality, speedy and correct target identification is a necessity. Recently, much work has been put into the development of automatic and semi-automatic segmentation tools, often using prior knowledge to constrain some grey level, or derivative thereof, interrogation algorithm. It is hoped that such techniques can be applied to organ at risk and tumour segmentation in radiotherapy. In this work, however, we make the assumption that grey levels do not necessarily determine a tumour's extent, especially in CT where the attenuation coefficient can often vary little between cancerous and normal tissue. In this context we present an algorithm that generates a discontinuity free delineation surface driven by user placed, evidence based support points. In regions of sparse user supplied information, prior knowledge, in the form of a statistical shape model, provides guidance. A small case study is used to illustrate the method. Multiple observers (between 3 and 7) used both the presented tool and a commercial manual contouring package to delineate the bladder on a serially imaged (10 cone beam CT volumes ) prostate patient. A previously presented shape analysis technique is used to quantitatively compare the observer variability.

  15. 3D dosimetry estimation for selective internal radiation therapy (SIRT) using SPECT/CT images: a phantom study

    Science.gov (United States)

    Debebe, Senait A.; Franquiz, Juan; McGoron, Anthony J.

    2015-03-01

    Selective Internal Radiation Therapy (SIRT) is a common way to treat liver cancer that cannot be treated surgically. SIRT involves administration of Yttrium - 90 (90Y) microspheres via the hepatic artery after a diagnostic procedure using 99mTechnetium (Tc)-macroaggregated albumin (MAA) to detect extrahepatic shunting to the lung or the gastrointestinal tract. Accurate quantification of radionuclide administered to patients and radiation dose absorbed by different organs is of importance in SIRT. Accurate dosimetry for SIRT allows optimization of dose delivery to the target tumor and may allow for the ability to assess the efficacy of the treatment. In this study, we proposed a method that can efficiently estimate radiation absorbed dose from 90Y bremsstrahlung SPECT/CT images of liver and the surrounding organs. Bremsstrahlung radiation from 90Y was simulated using the Compton window of 99mTc (78keV at 57%). 99mTc images acquired at the photopeak energy window were used as a standard to examine the accuracy of dosimetry prediction by the simulated bremsstrahlung images. A Liqui-Phil abdominal phantom with liver, stomach and two tumor inserts was imaged using a Philips SPECT/CT scanner. The Dose Point Kernel convolution method was used to find the radiation absorbed dose at a voxel level for a three dimensional dose distribution. This method will allow for a complete estimate of the distribution of radiation absorbed dose by tumors, liver, stomach and other surrounding organs at the voxel level. The method provides a quantitative predictive method for SIRT treatment outcome and administered dose response for patients who undergo the treatment.

  16. Application of 3D-myelo-CT for lumbar disease

    Energy Technology Data Exchange (ETDEWEB)

    Taira, Gaku; Endo, Kenji; Karasawa, Haruhiro; Urawa, Yasuhito; Ito, Koichi; Ichimaru, Katsuji [Tokyo Medical Coll., Ami, Ibaraki (Japan). Kasumigaura Hospital; Miura, Yukio

    1997-03-01

    Helical CTs for lumbar disk hernia (LDH) and for lumbar canal stenosis (LCS) were compared with ordinary imaging diagnosis. Subjects were 10 cases of LDH and of LCS, who were 24-71 (mean 58.7) years old. The apparatus was Siemens Somatom Plus 4 and its 3D-program soft was used for reconstruction. The ordinary myelography was performed with a non-ionic contrasting medium and 60 min later, helical CT was carried out with conditions of 140 kV, 204 mA, slice thickness 3 mm, bed speed 3 mm/sec and reconstruction 1.5 mm. MRI was done on sagittal, axial and coronary sections and 3D-MRI was reconstructed from the coronary ones with the maximum intensity projection procedure. The 3D-myelo-CT images were compared with those by myelography, 2D-MRI and 3D-MRI in diagnostic rate of impaired nerve root, anatomical relationships between dura tube and bony factors and imaging rate of redundant nerve root. Exclusions of dura tube and of nerve root were found observable in 3D-myelo-CT, which was useful for surgery simulation and for explaining to patients. (K.H.)

  17. Computer-aided diagnosis: a 3D segmentation method for lung nodules in CT images by use of a spiral-scanning technique

    Science.gov (United States)

    Wang, Jiahui; Engelmann, Roger; Li, Qiang

    2008-03-01

    Lung nodule segmentation in computed tomography (CT) plays an important role in computer-aided detection, diagnosis, and quantification systems for lung cancer. In this study, we developed a simple but accurate nodule segmentation method in three-dimensional (3D) CT. First, a volume of interest (VOI) was determined at the location of a nodule. We then transformed the VOI into a two-dimensional (2D) image by use of a "spiral-scanning" technique, in which a radial line originating from the center of the VOI spirally scanned the VOI. The voxels scanned by the radial line were arranged sequentially to form a transformed 2D image. Because the surface of a nodule in 3D image became a curve in the transformed 2D image, the spiral-scanning technique considerably simplified our segmentation method and enabled us to obtain accurate segmentation results. We employed a dynamic programming technique to delineate the "optimal" outline of a nodule in the 2D image, which was transformed back into the 3D image space to provide the interior of the nodule. The proposed segmentation method was trained on the first and was tested on the second Lung Image Database Consortium (LIDC) datasets. An overlap between nodule regions provided by computer and by the radiologists was employed as a performance metric. The experimental results on the LIDC database demonstrated that our segmentation method provided relatively robust and accurate segmentation results with mean overlap values of 66% and 64% for the nodules in the first and second LIDC datasets, respectively, and would be useful for the quantification, detection, and diagnosis of lung cancer.

  18. Method and phantom to study combined effects of in-plane (x,y) and z-axis resolution for 3D CT imaging.

    Science.gov (United States)

    Goodenough, David; Levy, Josh; Kristinsson, Smari; Fredriksson, Jesper; Olafsdottir, Hildur; Healy, Austin

    2016-09-08

    Increasingly, the advent of multislice CT scanners, volume CT scanners, and total body spiral acquisition modes has led to the use of Multi Planar Reconstruction and 3D datasets. In considering 3D resolution properties of a CT system it is important to note that both the in-plane (x,y) and z-axis (slice thickness) influence the visual-ization and detection of objects within the scanned volume. This study investigates ways to consider both the in-plane resolution and the z-axis resolution in a single phantom wherein analytic or visualized analysis can yield information on these combined effects. A new phantom called the "Wave Phantom" is developed that can be used to sample the 3D resolution properties of a CT image, including in-plane (x,y) and z-axis information. The key development in this Wave Phantom is the incorporation of a z-axis aspect of a more traditional step (bar) resolution gauge phantom. The phantom can be examined visually wherein a cutoff level may be seen; and/or the analytic analysis of the various characteristics of the waveform profile by including amplitude, frequency, and slope (rate of climb) of the peaks, can be extracted from the Wave Pattern using mathematical analysis such as the Fourier transform. The combined effect of changes in in-plane resolution and z-axis (thickness), are shown, as well as the effect of changes in either in-plane resolu-tion, or z-axis thickness. Examples of visual images of the Wave pattern as well as the analytic characteristics of the various harmonics of a periodic Wave pattern resulting from changes in resolution filter and/or slice thickness, and position in the field of view are shown. The Wave Phantom offers a promising way to investigate 3D resolution results from combined effect of in-plane (x-y) and z-axis resolution as contrasted to the use of simple 2D resolution gauges that need to be used with separate measures of z-axis dependency, such as angled ramps. It offers both a visual pattern as well as a

  19. Rigid model-based 3D segmentation of the bones of joints in MR and CT images for motion analysis.

    Science.gov (United States)

    Liu, Jiamin; Udupa, Jayaram K; Saha, Punam K; Odhner, Dewey; Hirsch, Bruce E; Siegler, Sorin; Simon, Scott; Winkelstein, Beth A

    2008-08-01

    There are several medical application areas that require the segmentation and separation of the component bones of joints in a sequence of images of the joint acquired under various loading conditions, our own target area being joint motion analysis. This is a challenging problem due to the proximity of bones at the joint, partial volume effects, and other imaging modality-specific factors that confound boundary contrast. In this article, a two-step model-based segmentation strategy is proposed that utilizes the unique context of the current application wherein the shape of each individual bone is preserved in all scans of a particular joint while the spatial arrangement of the bones alters significantly among bones and scans. In the first step, a rigid deterministic model of the bone is generated from a segmentation of the bone in the image corresponding to one position of the joint by using the live wire method. Subsequently, in other images of the same joint, this model is used to search for the same bone by minimizing an energy function that utilizes both boundary- and region-based information. An evaluation of the method by utilizing a total of 60 data sets on MR and CT images of the ankle complex and cervical spine indicates that the segmentations agree very closely with the live wire segmentations, yielding true positive and false positive volume fractions in the range 89%-97% and 0.2%-0.7%. The method requires 1-2 minutes of operator time and 6-7 min of computer time per data set, which makes it significantly more efficient than live wire-the method currently available for the task that can be used routinely.

  20. Glasses-free 3D viewing systems for medical imaging

    Science.gov (United States)

    Magalhães, Daniel S. F.; Serra, Rolando L.; Vannucci, André L.; Moreno, Alfredo B.; Li, Li M.

    2012-04-01

    In this work we show two different glasses-free 3D viewing systems for medical imaging: a stereoscopic system that employs a vertically dispersive holographic screen (VDHS) and a multi-autostereoscopic system, both used to produce 3D MRI/CT images. We describe how to obtain a VDHS in holographic plates optimized for this application, with field of view of 7 cm to each eye and focal length of 25 cm, showing images done with the system. We also describe a multi-autostereoscopic system, presenting how it can generate 3D medical imaging from viewpoints of a MRI or CT image, showing results of a 3D angioresonance image.

  1. Investigation on the 3 D geometric accuracy and on the image quality (MTF, SNR and NPS) of volume tomography units (CT, CBCT and DVT); Untersuchung zur geometrischen 3-D-Genauigkeit und zur Bildqualitaet (MTF, SRV und W) von Volumentomografie-Einrichtungen (CT, CBCT und DVT)

    Energy Technology Data Exchange (ETDEWEB)

    Blendl, C.; Selbach, M.; Uphoff, C. [Fachhochschule Koeln (Germany). Inst. fuer Medien- und Phototechnik; Fiebich, M.; Voigt, J.M. [Fachhochschule Giessen (DE). Inst. fuer Medizinische Physik und Strahlenschutz (IMPS)

    2012-01-15

    Purpose: The study aims at investigating how far image quality (MTF and NPS) differs in between CT, CBCT and DVT units and how far the geometrical 3 D accuracy and the HU calibration differ in respect to surgical or radio therapeutic planning. Materials and Methods: X ray image stacks have been made using a new designed test device which contains structures for measuring MTF, NPS, the 3 D accuracy and the Hounsfield calibration (jaw or skull program). The image stacks of the transversal images were analyzed with a dedicated computer program. Results: The MTF values are correlated with the physical resolution (CT and DVT) and are influenced by the used Kernel (CT). The NPS values are limited to an intra system comparison due to the insufficient HU accuracy. The 3 D accuracy is comparable in between the system types. Conclusions: The values of image quality are not yet correlated with dose values: NPS. Investigations to an appropriate dosimetry are ongoing to establish the ratio between dose and image quality (ALARA principle). No fundamental difference between the systems can be stated in respect radio therapeutic planning: improper HU calibration accuracy in CBCT and DVT units. The geometric 3 D accuracy of high performance DVT systems is greater than that of CT Systems. (orig.)

  2. 3-D Vector Flow Imaging

    DEFF Research Database (Denmark)

    Holbek, Simon

    studies and in vivo. Phantom measurements are compared with their corresponding reference value, whereas the in vivo measurement is validated against the current golden standard for non-invasive blood velocity estimates, based on magnetic resonance imaging (MRI). The study concludes, that a high precision......, if this significant reduction in the element count can still provide precise and robust 3-D vector flow estimates in a plane. The study concludes that the RC array is capable of estimating precise 3-D vector flow both in a plane and in a volume, despite the low channel count. However, some inherent new challenges......For the last decade, the field of ultrasonic vector flow imaging has gotten an increasingly attention, as the technique offers a variety of new applications for screening and diagnostics of cardiovascular pathologies. The main purpose of this PhD project was therefore to advance the field of 3-D...

  3. Effective incorporation of spatial information in a mutual information based 3D-2D registration of a CT volume to X-ray images.

    Science.gov (United States)

    Zheng, Guoyan

    2008-01-01

    This paper addresses the problem of estimating the 3D rigid pose of a CT volume of an object from its 2D X-ray projections. We use maximization of mutual information, an accurate similarity measure for multi-modal and mono-modal image registration tasks. However, it is known that the standard mutual information measure only takes intensity values into account without considering spatial information and its robustness is questionable. In this paper, instead of directly maximizing mutual information, we propose to use a variational approximation derived from the Kullback-Leibler bound. Spatial information is then incorporated into this variational approximation using a Markov random field model. The newly derived similarity measure has a least-squares form and can be effectively minimized by a multi-resolution Levenberg-Marquardt optimizer. Experimental results are presented on X-ray and CT datasets of a plastic phantom and a cadaveric spine segment.

  4. Imaging the Aqueous Humor Outflow Pathway in Human Eyes by Three-dimensional Micro-computed Tomography (3D micro-CT)

    Energy Technology Data Exchange (ETDEWEB)

    C Hann; M Bentley; A Vercnocke; E Ritman; M Fautsch

    2011-12-31

    The site of outflow resistance leading to elevated intraocular pressure in primary open-angle glaucoma is believed to be located in the region of Schlemm's canal inner wall endothelium, its basement membrane and the adjacent juxtacanalicular tissue. Evidence also suggests collector channels and intrascleral vessels may have a role in intraocular pressure in both normal and glaucoma eyes. Traditional imaging modalities limit the ability to view both proximal and distal portions of the trabecular outflow pathway as a single unit. In this study, we examined the effectiveness of three-dimensional micro-computed tomography (3D micro-CT) as a potential method to view the trabecular outflow pathway. Two normal human eyes were used: one immersion fixed in 4% paraformaldehyde and one with anterior chamber perfusion at 10 mmHg followed by perfusion fixation in 4% paraformaldehyde/2% glutaraldehyde. Both eyes were postfixed in 1% osmium tetroxide and scanned with 3D micro-CT at 2 {mu}m or 5 {mu}m voxel resolution. In the immersion fixed eye, 24 collector channels were identified with an average orifice size of 27.5 {+-} 5 {mu}m. In comparison, the perfusion fixed eye had 29 collector channels with a mean orifice size of 40.5 {+-} 13 {mu}m. Collector channels were not evenly dispersed around the circumference of the eye. There was no significant difference in the length of Schlemm's canal in the immersed versus the perfused eye (33.2 versus 35.1 mm). Structures, locations and size measurements identified by 3D micro-CT were confirmed by correlative light microscopy. These findings confirm 3D micro-CT can be used effectively for the non-invasive examination of the trabecular meshwork, Schlemm's canal, collector channels and intrascleral vasculature that comprise the distal outflow pathway. This imaging modality will be useful for non-invasive study of the role of the trabecular outflow pathway as a whole unit.

  5. Design, fabrication, and implementation of voxel-based 3D printed textured phantoms for task-based image quality assessment in CT

    Science.gov (United States)

    Solomon, Justin; Ba, Alexandre; Diao, Andrew; Lo, Joseph; Bier, Elianna; Bochud, François; Gehm, Michael; Samei, Ehsan

    2016-03-01

    In x-ray computed tomography (CT), task-based image quality studies are typically performed using uniform background phantoms with low-contrast signals. Such studies may have limited clinical relevancy for modern non-linear CT systems due to possible influence of background texture on image quality. The purpose of this study was to design and implement anatomically informed textured phantoms for task-based assessment of low-contrast detection. Liver volumes were segmented from 23 abdominal CT cases. The volumes were characterized in terms of texture features from gray-level co-occurrence and run-length matrices. Using a 3D clustered lumpy background (CLB) model, a fitting technique based on a genetic optimization algorithm was used to find the CLB parameters that were most reflective of the liver textures, accounting for CT system factors of spatial blurring and noise. With the modeled background texture as a guide, a cylinder phantom (165 mm in diameter and 30 mm height) was designed, containing 20 low-contrast spherical signals (6 mm in diameter at targeted contrast levels of ~3.2, 5.2, 7.2, 10, and 14 HU, 4 repeats per signal). The phantom was voxelized and input into a commercial multi-material 3D printer (Object Connex 350), with custom software for voxel-based printing. Using principles of digital half-toning and dithering, the 3D printer was programmed to distribute two base materials (VeroWhite and TangoPlus, nominal voxel size of 42x84x30 microns) to achieve the targeted spatial distribution of x-ray attenuation properties. The phantom was used for task-based image quality assessment of a clinically available iterative reconstruction algorithm (Sinogram Affirmed Iterative Reconstruction, SAFIRE) using a channelized Hotelling observer paradigm. Images of the textured phantom and a corresponding uniform phantom were acquired at six dose levels and observer model performance was estimated for each condition (5 contrasts x 6 doses x 2 reconstructions x 2

  6. Diffusible iodine-based contrast-enhanced computed tomography (diceCT): an emerging tool for rapid, high-resolution, 3-D imaging of metazoan soft tissues.

    Science.gov (United States)

    Gignac, Paul M; Kley, Nathan J; Clarke, Julia A; Colbert, Matthew W; Morhardt, Ashley C; Cerio, Donald; Cost, Ian N; Cox, Philip G; Daza, Juan D; Early, Catherine M; Echols, M Scott; Henkelman, R Mark; Herdina, A Nele; Holliday, Casey M; Li, Zhiheng; Mahlow, Kristin; Merchant, Samer; Müller, Johannes; Orsbon, Courtney P; Paluh, Daniel J; Thies, Monte L; Tsai, Henry P; Witmer, Lawrence M

    2016-06-01

    Morphologists have historically had to rely on destructive procedures to visualize the three-dimensional (3-D) anatomy of animals. More recently, however, non-destructive techniques have come to the forefront. These include X-ray computed tomography (CT), which has been used most commonly to examine the mineralized, hard-tissue anatomy of living and fossil metazoans. One relatively new and potentially transformative aspect of current CT-based research is the use of chemical agents to render visible, and differentiate between, soft-tissue structures in X-ray images. Specifically, iodine has emerged as one of the most widely used of these contrast agents among animal morphologists due to its ease of handling, cost effectiveness, and differential affinities for major types of soft tissues. The rapid adoption of iodine-based contrast agents has resulted in a proliferation of distinct specimen preparations and scanning parameter choices, as well as an increasing variety of imaging hardware and software preferences. Here we provide a critical review of the recent contributions to iodine-based, contrast-enhanced CT research to enable researchers just beginning to employ contrast enhancement to make sense of this complex new landscape of methodologies. We provide a detailed summary of recent case studies, assess factors that govern success at each step of the specimen storage, preparation, and imaging processes, and make recommendations for standardizing both techniques and reporting practices. Finally, we discuss potential cutting-edge applications of diffusible iodine-based contrast-enhanced computed tomography (diceCT) and the issues that must still be overcome to facilitate the broader adoption of diceCT going forward.

  7. Total-liver-volume perfusion CT using 3-D image fusion to improve detection and characterization of liver metastases

    NARCIS (Netherlands)

    Meijerink, Martijn; Waesberghe, van Jan; Weide, van der Lineke; Tol, van den Petrousjka; Meijer, Sybren; Kuijk, van Cornelis

    2008-01-01

    The purpose of this study was to evaluate the feasibility of a totalliver- volume perfusion CT (CTP) technique for the detection and characterization of livermetastases. Twenty patients underwent helical CT of the total liver volume before and 11 times after intravenous contrast-material injection.

  8. 3D vector flow imaging

    DEFF Research Database (Denmark)

    Pihl, Michael Johannes

    The main purpose of this PhD project is to develop an ultrasonic method for 3D vector flow imaging. The motivation is to advance the field of velocity estimation in ultrasound, which plays an important role in the clinic. The velocity of blood has components in all three spatial dimensions, yet...... conventional methods can estimate only the axial component. Several approaches for 3D vector velocity estimation have been suggested, but none of these methods have so far produced convincing in vivo results nor have they been adopted by commercial manufacturers. The basis for this project is the Transverse...... on the TO fields are suggested. They can be used to optimize the TO method. In the third part, a TO method for 3D vector velocity estimation is proposed. It employs a 2D phased array transducer and decouples the velocity estimation into three velocity components, which are estimated simultaneously based on 5...

  9. 3D/2D Registration of medical images

    OpenAIRE

    Tomaževič, D.

    2008-01-01

    The topic of this doctoral dissertation is registration of 3D medical images to corresponding projective 2D images, referred to as 3D/2D registration. There are numerous possible applications of 3D/2D registration in image-aided diagnosis and treatment. In most of the applications, 3D/2D registration provides the location and orientation of the structures in a preoperative 3D CT or MR image with respect to intraoperative 2D X-ray images. The proposed doctoral dissertation tries to find origin...

  10. [A study on individual mandibular prostheses according to 3D reconstruction of CT images and CNC simulation method].

    Science.gov (United States)

    Pan, Liu-guo; Sun, Li-qun

    2007-03-01

    The new method of manufacturing individual mandibular prostheses, in combination with CT data and CNC technique, can duplicate bone tissues accurately, and can have the individual mandibular prosthesis made to order, and repair the mandibular defect (especially the lager mandibular segmental defect).

  11. ACM-based automatic liver segmentation from 3-D CT images by combining multiple atlases and improved mean-shift techniques.

    Science.gov (United States)

    Ji, Hongwei; He, Jiangping; Yang, Xin; Deklerck, Rudi; Cornelis, Jan

    2013-05-01

    In this paper, we present an autocontext model(ACM)-based automatic liver segmentation algorithm, which combines ACM, multiatlases, and mean-shift techniques to segment liver from 3-D CT images. Our algorithm is a learning-based method and can be divided into two stages. At the first stage, i.e., the training stage, ACM is performed to learn a sequence of classifiers in each atlas space (based on each atlas and other aligned atlases). With the use of multiple atlases, multiple sequences of ACM-based classifiers are obtained. At the second stage, i.e., the segmentation stage, the test image will be segmented in each atlas space by applying each sequence of ACM-based classifiers. The final segmentation result will be obtained by fusing segmentation results from all atlas spaces via a multiclassifier fusion technique. Specially, in order to speed up segmentation, given a test image, we first use an improved mean-shift algorithm to perform over-segmentation and then implement the region-based image labeling instead of the original inefficient pixel-based image labeling. The proposed method is evaluated on the datasets of MICCAI 2007 liver segmentation challenge. The experimental results show that the average volume overlap error and the average surface distance achieved by our method are 8.3% and 1.5 m, respectively, which are comparable to the results reported in the existing state-of-the-art work on liver segmentation.

  12. 3D inpatient dose reconstruction from the PET-CT imaging of {sup 90}Y microspheres for metastatic cancer to the liver: Feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Fourkal, E.; Veltchev, I.; Lin, M.; Meyer, J. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States); Koren, S. [Department of Radiation Oncology, Beth Israel Comprehensive Cancer Center, New York, New York 10011 (United States); Doss, M.; Yu, J. Q. [Department of Diagnostic Imaging, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States)

    2013-08-15

    Purpose: The introduction of radioembolization with microspheres represents a significant step forward in the treatment of patients with metastatic disease to the liver. This technique uses semiempirical formulae based on body surface area or liver and target volumes to calculate the required total activity for a given patient. However, this treatment modality lacks extremely important information, which is the three-dimensional (3D) dose delivered by microspheres to different organs after their administration. The absence of this information dramatically limits the clinical efficacy of this modality, specifically the predictive power of the treatment. Therefore, the aim of this study is to develop a 3D dose calculation technique that is based on the PET imaging of the infused microspheres.Methods: The Fluka Monte Carlo code was used to calculate the voxel dose kernel for {sup 90}Y source with voxel size equal to that of the PET scan. The measured PET activity distribution was converted to total activity distribution for the subsequent convolution with the voxel dose kernel to obtain the 3D dose distribution. In addition, dose-volume histograms were generated to analyze the dose to the tumor and critical structures.Results: The 3D inpatient dose distribution can be reconstructed from the PET data of a patient scanned after the infusion of microspheres. A total of seven patients have been analyzed so far using the proposed reconstruction method. Four patients underwent treatment with SIR-Spheres for liver metastases from colorectal cancer and three patients were treated with Therasphere for hepatocellular cancer. A total of 14 target tumors were contoured on post-treatment PET-CT scans for dosimetric evaluation. Mean prescription activity was 1.7 GBq (range: 0.58–3.8 GBq). The resulting mean maximum measured dose to targets was 167 Gy (range: 71–311 Gy). Mean minimum dose to 70% of target (D70) was 68 Gy (range: 25–155 Gy). Mean minimum dose to 90% of target

  13. A semi-automatic method to extract canal pathways in 3D micro-CT images of Octocorals.

    Directory of Open Access Journals (Sweden)

    Alfredo Morales Pinzón

    Full Text Available The long-term goal of our study is to understand the internal organization of the octocoral stem canals, as well as their physiological and functional role in the growth of the colonies, and finally to assess the influence of climatic changes on this species. Here we focus on imaging tools, namely acquisition and processing of three-dimensional high-resolution images, with emphasis on automated extraction of canal pathways. Our aim was to evaluate the feasibility of the whole process, to point out and solve - if possible - technical problems related to the specimen conditioning, to determine the best acquisition parameters and to develop necessary image-processing algorithms. The pathways extracted are expected to facilitate the structural analysis of the colonies, namely to help observing the distribution, formation and number of canals along the colony. Five volumetric images of Muricea muricata specimens were successfully acquired by X-ray computed tomography with spatial resolution ranging from 4.5 to 25 micrometers. The success mainly depended on specimen immobilization. More than [Formula: see text] of the canals were successfully detected and tracked by the image-processing method developed. Thus obtained three-dimensional representation of the canal network was generated for the first time without the need of histological or other destructive methods. Several canal patterns were observed. Although most of them were simple, i.e. only followed the main branch or "turned" into a secondary branch, many others bifurcated or fused. A majority of bifurcations were observed at branching points. However, some canals appeared and/or ended anywhere along a branch. At the tip of a branch, all canals fused into a unique chamber. Three-dimensional high-resolution tomographic imaging gives a non-destructive insight to the coral ultrastructure and helps understanding the organization of the canal network. Advanced image-processing techniques greatly

  14. Integration of 3D scale-based pseudo-enhancement correction and partial volume image segmentation for improving electronic colon cleansing in CT colonograpy.

    Science.gov (United States)

    Zhang, Hao; Li, Lihong; Zhu, Hongbin; Han, Hao; Song, Bowen; Liang, Zhengrong

    2014-01-01

    Orally administered tagging agents are usually used in CT colonography (CTC) to differentiate residual bowel content from native colonic structures. However, the high-density contrast agents tend to introduce pseudo-enhancement (PE) effect on neighboring soft tissues and elevate their observed CT attenuation value toward that of the tagged materials (TMs), which may result in an excessive electronic colon cleansing (ECC) since the pseudo-enhanced soft tissues are incorrectly identified as TMs. To address this issue, we integrated a 3D scale-based PE correction into our previous ECC pipeline based on the maximum a posteriori expectation-maximization partial volume (PV) segmentation. The newly proposed ECC scheme takes into account both the PE and PV effects that commonly appear in CTC images. We evaluated the new scheme on 40 patient CTC scans, both qualitatively through display of segmentation results, and quantitatively through radiologists' blind scoring (human observer) and computer-aided detection (CAD) of colon polyps (computer observer). Performance of the presented algorithm has shown consistent improvements over our previous ECC pipeline, especially for the detection of small polyps submerged in the contrast agents. The CAD results of polyp detection showed that 4 more submerged polyps were detected for our new ECC scheme over the previous one.

  15. Comprehensive Non-Destructive Conservation Documentation of Lunar Samples Using High-Resolution Image-Based 3D Reconstructions and X-Ray CT Data

    Science.gov (United States)

    Blumenfeld, E. H.; Evans, C. A.; Oshel, E. R.; Liddle, D. A.; Beaulieu, K.; Zeigler, R. A.; Hanna, R. D.; Ketcham, R. A.

    2015-01-01

    Established contemporary conservation methods within the fields of Natural and Cultural Heritage encourage an interdisciplinary approach to preservation of heritage material (both tangible and intangible) that holds "Outstanding Universal Value" for our global community. NASA's lunar samples were acquired from the moon for the primary purpose of intensive scientific investigation. These samples, however, also invoke cultural significance, as evidenced by the millions of people per year that visit lunar displays in museums and heritage centers around the world. Being both scientifically and culturally significant, the lunar samples require a unique conservation approach. Government mandate dictates that NASA's Astromaterials Acquisition and Curation Office develop and maintain protocols for "documentation, preservation, preparation and distribution of samples for research, education and public outreach" for both current and future collections of astromaterials. Documentation, considered the first stage within the conservation methodology, has evolved many new techniques since curation protocols for the lunar samples were first implemented, and the development of new documentation strategies for current and future astromaterials is beneficial to keeping curation protocols up to date. We have developed and tested a comprehensive non-destructive documentation technique using high-resolution image-based 3D reconstruction and X-ray CT (XCT) data in order to create interactive 3D models of lunar samples that would ultimately be served to both researchers and the public. These data enhance preliminary scientific investigations including targeted sample requests, and also provide a new visual platform for the public to experience and interact with the lunar samples. We intend to serve these data as they are acquired on NASA's Astromaterials Acquisistion and Curation website at http://curator.jsc.nasa.gov/. Providing 3D interior and exterior documentation of astromaterial

  16. Effective incorporating spatial information in a mutual information based 3D-2D registration of a CT volume to X-ray images.

    Science.gov (United States)

    Zheng, Guoyan

    2010-10-01

    This paper addresses the problem of estimating the 3D rigid poses of a CT volume of an object from its 2D X-ray projection(s). We use maximization of mutual information, an accurate similarity measure for multi-modal and mono-modal image registration tasks. However, it is known that the standard mutual information measures only take intensity values into account without considering spatial information and their robustness is questionable. In this paper, instead of directly maximizing mutual information, we propose to use a variational approximation derived from the Kullback-Leibler bound. Spatial information is then incorporated into this variational approximation using a Markov random field model. The newly derived similarity measure has a least-squares form and can be effectively minimized by a multi-resolution Levenberg-Marquardt optimizer. Experiments were conducted on datasets from two applications: (a) intra-operative patient pose estimation from a limited number (e.g. 2) of calibrated fluoroscopic images, and (b) post-operative cup orientation estimation from a single standard X-ray radiograph with/without gonadal shielding. The experiment on intra-operative patient pose estimation showed a mean target registration accuracy of 0.8mm and a capture range of 11.5mm, while the experiment on estimating the post-operative cup orientation from a single X-ray radiograph showed a mean accuracy below 2 degrees for both anteversion and inclination. More importantly, results from both experiments demonstrated that the newly derived similarity measures were robust to occlusions in the X-ray image(s).

  17. Self-calibration of cone-beam CT geometry using 3D-2D image registration: development and application to tasked-based imaging with a robotic C-arm

    Science.gov (United States)

    Ouadah, S.; Stayman, J. W.; Gang, G.; Uneri, A.; Ehtiati, T.; Siewerdsen, J. H.

    2015-03-01

    Purpose: Robotic C-arm systems are capable of general noncircular orbits whose trajectories can be driven by the particular imaging task. However obtaining accurate calibrations for reconstruction in such geometries can be a challenging problem. This work proposes a method to perform a unique geometric calibration of an arbitrary C-arm orbit by registering 2D projections to a previously acquired 3D image to determine the transformation parameters representing the system geometry. Methods: Experiments involved a cone-beam CT (CBCT) bench system, a robotic C-arm, and three phantoms. A robust 3D-2D registration process was used to compute the 9 degree of freedom (DOF) transformation between each projection and an existing 3D image by maximizing normalized gradient information with a digitally reconstructed radiograph (DRR) of the 3D volume. The quality of the resulting "self-calibration" was evaluated in terms of the agreement with an established calibration method using a BB phantom as well as image quality in the resulting CBCT reconstruction. Results: The self-calibration yielded CBCT images without significant difference in spatial resolution from the standard ("true") calibration methods (p-value >0.05 for all three phantoms), and the differences between CBCT images reconstructed using the "self" and "true" calibration methods were on the order of 10-3 mm-1. Maximum error in magnification was 3.2%, and back-projection ray placement was within 0.5 mm. Conclusion: The proposed geometric "self" calibration provides a means for 3D imaging on general noncircular orbits in CBCT systems for which a geometric calibration is either not available or not reproducible. The method forms the basis of advanced "task-based" 3D imaging methods now in development for robotic C-arms.

  18. Multiplanar and 3D CT of acetabular fractures

    Energy Technology Data Exchange (ETDEWEB)

    Haveri, M.; Suramo, I.; Laehde, S. [Oulu Univ., Dept. of Diagnostic Radiology (Finland); Junila, J. [Oulu Univ., Dept. of Orthopaedic Surgery (Finland)

    1998-05-01

    Purpose: To establish a standard protocol for the multiplanar (MPR) and 3D shaded surface display (SSD) reconstruction of CT data on acetabular fractures, and to assess the usefulness of these reformats. Material and Methods: Acetabular fractures in 15 patients were imaged by means of plain radiographs, transaxial CT, MPR reformats, and SSD reformats. Results: The classification of the acetabular fracture was revised in 7/15 cases when the transaxial CT images were read after the plain radiographs. Although the MPR and SSD reformats did not alter the classification, they did add to the degree of confidence in the diagnosis in 9/15 cases. In 2 patients, the MPR and SSD reformats indicated operative instead of conservative treatment. In the MPR reformats, the following views were considered essential in all cases: (a) along the anterior column; (b) along the posterior column; and (c) along both columns and the inferior ramus. In the SSD reformats, the following views were considered essential in all cases: (d) the latero-caudal en face view into the acetabulum; and 180 opposite to this, (e) the medio-cranial view (facing the quadrilateral plate). In 10/15 cases, these views were all that was needed for classification. It was, however, essential to remove the femur from the images before reconstructing the SSD views. Conclusion: Complex acetabular fractures with displacement should be evaluated by means of transaxial CT and additional MPR and SSD reformats. The use of appropriate standard MPR and SSD views shortens the time required to produce the reformats and thereby maximizes the benefit gained. (orig.).

  19. Atlas Based Automatic Liver 3D CT Image Segmentation%基于图谱的肝脏CT三维自动分割研究

    Institute of Scientific and Technical Information of China (English)

    刘伟; 贾富仓; 胡庆茂; 王俊

    2011-01-01

    目的 在肝脏外科手术或肝脏病理研究中,计算肝脏体积是重要步骤.由于肝脏外形复杂、临近组织灰度值与之接近等特点,肝脏的自动医学图像分割仍是医学图像处理中的难点之一.方法 本文采用图谱结合3D非刚性配准的方法,同时加入肝脏区域搜索算法,实现了鲁棒性较高的肝脏自动分割程序.首先,利用20套训练图像创建图谱,然后程序自动搜索肝脏区域,最后将图谱与待分割CT图像依次进行仿射配准和B样条配准.配准以后的图谱肝脏轮廓即可表示为目标肝脏分割轮廓,进而计算出肝脏体积.结果 评估结果显示,上述方法在肝脏体积误差方面表现出色,达到77分,但在局部(主要在肝脏尖端)出现较大的误差.结论 该方法分割临床肝脏CT图像具有可行性.%Objective Liver segmentation is an important step for the planning and navigation in liver surgery. Accurate, fast and robust automatic segmentation methods for clinical routine data are urgently needed. Because of the liver- s characteristics, such as the complexity of the external form, the similarity between the intensities of the liver and the tissues around it, automatic segmentation of the liver is one of the difficulties in medical image processing. Methods In this paper, 3D non-rigid registration from a refined atlas to liver CT images is used for segmentation. Firstly, twenty sets of training images are utilized to create an atlas. Then the liver initial region is searched and located automatically. After that threshold filtering is used to enhance the robustness of segmentation. Finally, this atlas is non-rigidly registered to the liver in CT images with affine and B-spline in succession. The registered segmentation of liver- s atlas represented the segmentation of the target liver, and then the liver volume was calculated. Results The evaluation show that the proposed method works well in liver volume error, with the 77 score

  20. A system for finding a 3D target without a 3D image

    Science.gov (United States)

    West, Jay B.; Maurer, Calvin R., Jr.

    2008-03-01

    We present here a framework for a system that tracks one or more 3D anatomical targets without the need for a preoperative 3D image. Multiple 2D projection images are taken using a tracked, calibrated fluoroscope. The user manually locates each target on each of the fluoroscopic views. A least-squares minimization algorithm triangulates the best-fit position of each target in the 3D space of the tracking system: using the known projection matrices from 3D space into image space, we use matrix minimization to find the 3D position that projects closest to the located target positions in the 2D images. A tracked endoscope, whose projection geometry has been pre-calibrated, is then introduced to the operating field. Because the position of the targets in the tracking space is known, a rendering of the targets may be projected onto the endoscope view, thus allowing the endoscope to be easily brought into the target vicinity even when the endoscope field of view is blocked, e.g. by blood or tissue. An example application for such a device is trauma surgery, e.g., removal of a foreign object. Time, scheduling considerations and concern about excessive radiation exposure may prohibit the acquisition of a 3D image, such as a CT scan, which is required for traditional image guidance systems; it is however advantageous to have 3D information about the target locations available, which is not possible using fluoroscopic guidance alone.

  1. Estimation of regional myocardial mass at risk based on distal arterial lumen volume and length using 3D micro-CT images.

    Science.gov (United States)

    Le, Huy; Wong, Jerry T; Molloi, Sabee

    2008-09-01

    The determination of regional myocardial mass at risk distal to a coronary occlusion provides valuable prognostic information for a patient with coronary artery disease. The coronary arterial system follows a design rule which allows for the use of arterial branch length and lumen volume to estimate regional myocardial mass at risk. Image processing techniques, such as segmentation, skeletonization and arterial network tracking, are presented for extracting anatomical details of the coronary arterial system using micro-computed tomography (micro-CT). Moreover, a method of assigning tissue voxels to their corresponding arterial branches is presented to determine the dependent myocardial region. The proposed micro-CT technique was utilized to investigate the relationship between the sum of the distal coronary arterial branch lengths and volumes to the dependent regional myocardial mass using a polymer cast of a porcine heart. The correlations of the logarithm of the total distal arterial lengths (L) to the logarithm of the regional myocardial mass (M) for the left anterior descending (LAD), left circumflex (LCX) and right coronary (RCA) arteries were log(L)=0.73log(M)+0.09 (R=0.78), log(L)=0.82log(M)+0.05 (R=0.77) and log(L)=0.85log(M)+0.05 (R=0.87), respectively. The correlation of the logarithm of the total distal arterial lumen volumes (V) to the logarithm of the regional myocardial mass for the LAD, LCX and RCA were log(V)=0.93log(M)-1.65 (R=0.81), log(V)=1.02log(M)-1.79 (R=0.78) and log(V)=1.17log(M)-2.10 (R=0.82), respectively. These morphological relations did not change appreciably for diameter truncations of 600-1400microm. The results indicate that the image processing procedures successfully extracted information from a large 3D dataset of the coronary arterial tree to provide prognostic indications in the form of arterial tree parameters and anatomical area at risk.

  2. Scaling relations between bone volume and bone structure as found using 3D µCT images of the trabecular bone taken from different skeletal sites

    Science.gov (United States)

    Raeth, Christoph; Müller, Dirk; Sidorenko, Irina; Monetti, Roberto; Eckstein, Felix; Matsuura, Maiko; Lochmüller, Eva-Maria; Zysset, Philippe K.; Bauer, Jan

    2010-03-01

    According to Wolff's law bone remodels in response to the mechanical stresses it experiences so as to produce a minimal-weight structure that is adapted to its applied stresses. Here, we investigate the relations between bone volume and structure for the trabecular bone using 3D μCT images taken from different skeletal sites in vitro, namely from the distal radii (96 specimens), thoracic (73 specimens) and lumbar vertebrae (78 specimens). We determine the local structure of the trabecular network by calculating isotropic and anisotropic scaling indices (α, αz). These measures have been proven to be able to discriminate rod- from sheet-like structures and to quantify the alignment of structures with respect to a preferential direction as given by the direction of the external force. Comparing global structure measures derived from the scaling indices (mean, standard deviation) with the bone mass (BV/TV) we find that all correlations obey very accurately power laws with scaling exponents of 0.14, 0.12, 0.15 (~), -0.2, -017, -0.17 (σ(αz)), 0.09, 0.05, 0.07 (~) and -0.20, -0.11 ,-0.13 (σ(αz)) distal radius, thoracic vertebra and lumbar vertebra respectively. Thus, these relations turn out to be site-independent, albeit the mechanical stresses to which the bones of the forearm and the spine are exposed, are quite different. The similar alignment might not be in agreement with a universal validity of Wolff's law. On the other hand, such universal power law relations may allow to develop additional diagnostic means to better assess healthy and osteoporotic bone.

  3. 基于体表定位的PET/CT/MRI"二机三维"图像融合的数字化对照%Evaluation of 3D Image Fusion between PET, CT and MRI Based on Somatotopic Localization

    Institute of Scientific and Technical Information of China (English)

    彭鳒侨; 卢永辉; 李颖; 李新春; 朱巧洪; 刘襄平; 成功

    2011-01-01

    Purpose:Attempt a localization registration approach of 2- Dimension (2D) images based on somatotopic localization to achieve accurate fusion of 3- Dimension (3D) images from modalities of PET,CT and MR one by one. Methods: The original data of PET, CT and MR were converted into digital format after input. Cubic localization solution of“9 - point & 3 - plane” was designed for registration. Image fusion was completed at a real - time workstation Mimics based on auto - fusing style of information exchanged by signal overlaid technique. Results: The fused cubic images of cross modality from CT + MR,PET + MR and PET + CT were mutually practiced on cranium, chest and knee samples from lung cancer patients. Distinct complementary images of simultaneously distinguishing pathological changes nature and location between soft and hard tissue were created. Conclusion:This advanced digital algorithm for cross modality fusion is of clinical significance to improve early diagnosis and differential diagnosis, although the cross modality processing is not completely through concurrently as single modality PET + CT, this experiment will provide experience drawn on invention of CT + MRI or PET + MR single modality equipment for medical imaging enterprise in development.%目的:尝试一种基于体表定位的二维图像配准方法,逐一实现PET、MRI和CT异机图像之间的精确三维融合.方法:输入PET/CT/MRI原始数据后采用数字化格式转换,设计"9点3面"立体定位法进行配准,在实时工作站Mimics按照信息交互自动融合模式,通过讯号叠加技术完成图像融合.结果:以肺癌患者的头、胸、膝为实例交叉试验CT+MRI、PET+MRI和PET+CT立体图像的异机融合,生成了分辨软、硬组织病变性质和位置的清晰互补影像.结论:这种先进的数字化融合算法对提高早期诊断和鉴别诊断具有临床意义,虽然异机融合工序目前尚未像PET+CT的同机融合那样完全成熟,但这一

  4. The effect of activity outside the field of view on image quality for a 3D LSO-based whole body PET/CT scanner.

    Science.gov (United States)

    Matheoud, R; Secco, C; Della Monica, P; Leva, L; Sacchetti, G; Inglese, E; Brambilla, M

    2009-10-07

    The purpose of this study was to quantify the influence of outside field of view (FOV) activity concentration (A(c)(,out)) on the noise equivalent count rate (NECR), scatter fraction (SF) and image quality of a 3D LSO whole-body PET/CT scanner. The contrast-to-noise ratio (CNR) was the figure of merit used to characterize the image quality of PET scans. A modified International Electrotechnical Commission (IEC) phantom was used to obtain SF and counting rates similar to those found in average patients. A scatter phantom was positioned at the end of the modified IEC phantom to simulate an activity that extends beyond the scanner. The modified IEC phantom was filled with (18)F (11 kBq mL(-1)) and the spherical targets, with internal diameter (ID) ranging from 10 to 37 mm, had a target-to-background ratio of 10. PET images were acquired with background activity concentrations into the FOV (A(c)(,bkg)) about 11, 9.2, 6.6, 5.2 and 3.5 kBq mL(-1). The emission scan duration (ESD) was set to 1, 2, 3 and 4 min. The tube inside the scatter phantom was filled with activities to provide A(c)(,out) in the whole scatter phantom of zero, half, unity, twofold and fourfold the one of the modified IEC phantom. Plots of CNR versus the various parameters are provided. Multiple linear regression was employed to study the effects of A(c)(,out) on CNR, adjusted for the presence of variables (sphere ID, A(c)(,bkg) and ESD) related to CNR. The presence of outside FOV activity at the same concentration as the one inside the FOV reduces peak NECR of 30%. The increase in SF is marginal (1.2%). CNR diminishes significantly with increasing outside FOV activity, in the range explored. ESD and A(c)(,out) have a similar weight in accounting for CNR variance. Thus, an experimental law that adjusts the scan duration to the outside FOV activity can be devised. Recovery of CNR loss due to an elevated A(c)(,out) activity seems feasible by modulating the ESD in individual bed positions according to A(c)(,out).

  5. Comparison of radiation dose and image quality of Siremobil-IsoC{sup 3D} with a 16-slice spiral CT for diagnosis and intervention in the human pelvic bone; Vergleich von Strahlenexposition und Bildqualitaet eines Siremobil-IsoC{sup 3D} mit einem 16-Zeilen-Spiral-CT bei Diagnostik und Intervention am humanen Becken

    Energy Technology Data Exchange (ETDEWEB)

    Wieners, G.; Pech, M.; Beck, A.; Wust, P.; Felix, R.; Schroeder, R.J. [Klinik fuer Strahlenheilkunde, Charite, Univ. Berlin (Germany); Koenig, B.; Erdmenger, U.; Stoeckle, U. [Klinik fuer Unfallchirurgie, Charite, Univ. Berlin (Germany)

    2005-02-01

    Purpose: to compare the image quality of 16-slice computed tomography with the image quality of Siremobil-IsoC{sup 3D} of the pelvic region and to measure simultaneously the radiation dose before and after implantation of a sacroiliac screw (SI-screw) Materials and methods: the pelvic region of 8 human cadavers was examined in the Siremobil-IsoC{sup 3D} at five different levels. We used a standard protocol for the 16-slice CT of the complete pelvic region before and after insertion of a pelvic screw, followed by stepwise reduction of the tube current to find the tube current that equalizes the image quality of both modalities. We controlled the image quality by judging important structures such as neuroforamen, nerves, sacroiliacal joint space, intervertebral space, osteophytes, iliopsoas muscle, acetabular surface, fovea centralis, hip joint and os pubis. The image quality was judged by three radiologists and three trauma surgeons using a ranking from 1 to 5. The dose was measured with an endorectally placed NOMEX Dosimeter, to obtain the gonadal dose. Results: the medium score for all viewers of the Siremobil-IsoC{sup 3D} examinations was between 3 and 4.3. The medium score for all CT-examinations with a tube current of 250 mA was between 1.3 and 2.2. The reduction of tube current down to 80 mA hardly influenced the marks for the analyzed structures. Under 80 mA, bony structures, even after implantation of a SI-screw, were still marked as good, but soft tissue differentiation was getting worse. For the examination of the pelvis, the average dose-length product for the IsoC{sup 3D} was 41.2 mGy x cm. The medium dose-length product for CT was 389 mGy x cm for 250 mA, 125 mGy x cm for 80 mA and 82 mGy x cm for 60 mA. (orig.)

  6. 3D intrathoracic region definition and its application to PET-CT analysis

    Science.gov (United States)

    Cheirsilp, Ronnarit; Bascom, Rebecca; Allen, Thomas W.; Higgins, William E.

    2014-03-01

    Recently developed integrated PET-CT scanners give co-registered multimodal data sets that offer complementary three-dimensional (3D) digital images of the chest. PET (positron emission tomography) imaging gives highly specific functional information of suspect cancer sites, while CT (X-ray computed tomography) gives associated anatomical detail. Because the 3D CT and PET scans generally span the body from the eyes to the knees, accurate definition of the intrathoracic region is vital for focusing attention to the central-chest region. In this way, diagnostically important regions of interest (ROIs), such as central-chest lymph nodes and cancer nodules, can be more efficiently isolated. We propose a method for automatic segmentation of the intrathoracic region from a given co-registered 3D PET-CT study. Using the 3D CT scan as input, the method begins by finding an initial intrathoracic region boundary for a given 2D CT section. Next, active contour analysis, driven by a cost function depending on local image gradient, gradient-direction, and contour shape features, iteratively estimates the contours spanning the intrathoracic region on neighboring 2D CT sections. This process continues until the complete region is defined. We next present an interactive system that employs the segmentation method for focused 3D PET-CT chest image analysis. A validation study over a series of PET-CT studies reveals that the segmentation method gives a Dice index accuracy of less than 98%. In addition, further results demonstrate the utility of the method for focused 3D PET-CT chest image analysis, ROI definition, and visualization.

  7. SU-C-BRB-06: Utilizing 3D Scanner and Printer for Dummy Eye-Shield: Artifact-Free CT Images of Tungsten Eye-Shield for Accurate Dose Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Park, J; Lee, J [Program in Biomedical Radiation Sciences, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul (Korea, Republic of); Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul (Korea, Republic of); Kim, H [Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul (Korea, Republic of); Interdisciplinary Program in Radiation Applied Life Science, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, I [Department of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of); Interdisciplinary Program in Radiation Applied Life Science, Seoul National University College of Medicine, Seoul (Korea, Republic of); Ye, S [Program in Biomedical Radiation Sciences, Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul (Korea, Republic of); Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul (Korea, Republic of); Department of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of); Interdisciplinary Program in Radiation Applied Life Science, Seoul National University College of Medicine, Seoul (Korea, Republic of); Advanced Institutes of Convergence Technology, Seoul National University, Suwon (Korea, Republic of)

    2015-06-15

    Purpose: To evaluate the effect of a tungsten eye-shield on the dose distribution of a patient. Methods: A 3D scanner was used to extract the dimension and shape of a tungsten eye-shield in the STL format. Scanned data was transferred into a 3D printer. A dummy eye shield was then produced using bio-resin (3D systems, VisiJet M3 Proplast). For a patient with mucinous carcinoma, the planning CT was obtained with the dummy eye-shield placed on the patient’s right eye. Field shaping of 6 MeV was performed using a patient-specific cerrobend block on the 15 x 15 cm{sup 2} applicator. The gantry angle was 330° to cover the planning target volume near by the lens. EGS4/BEAMnrc was commissioned from our measurement data from a Varian 21EX. For the CT-based dose calculation using EGS4/DOSXYZnrc, the CT images were converted to a phantom file through the ctcreate program. The phantom file had the same resolution as the planning CT images. By assigning the CT numbers of the dummy eye-shield region to 17000, the real dose distributions below the tungsten eye-shield were calculated in EGS4/DOSXYZnrc. In the TPS, the CT number of the dummy eye-shield region was assigned to the maximum allowable CT number (3000). Results: As compared to the maximum dose, the MC dose on the right lens or below the eye shield area was less than 2%, while the corresponding RTP calculated dose was an unrealistic value of approximately 50%. Conclusion: Utilizing a 3D scanner and a 3D printer, a dummy eye-shield for electron treatment can be easily produced. The artifact-free CT images were successfully incorporated into the CT-based Monte Carlo simulations. The developed method was useful in predicting the realistic dose distributions around the lens blocked with the tungsten shield.

  8. Imagens em 2D e 3D geradas pela TC Cone-Beam e radiografias convencionais: qual a mais confiável? 2D / 3D Cone-Beam CT images or conventional radiography: which is more reliable?

    Directory of Open Access Journals (Sweden)

    Carolina Perez Couceiro

    2010-10-01

    Full Text Available OBJETIVO: comparar a confiabilidade de identificação dos pontos visualizados sobre radiografias cefalométricas convencionais e sobre imagens geradas pela Tomografia Computadorizada Cone-Beam em 2D e 3D. MÉTODOS: o material constou de imagens obtidas através do tomógrafo computadorizado Cone-Beam, em norma lateral, em 2D e 3D, impressas em papel fotográfico; e radiografias cefalométricas laterais, realizadas na mesma clínica radiológica e no mesmo dia, de dois pacientes pertencentes aos arquivos do Curso de Especialização em Ortodontia da Faculdade de Odontologia da Universidade Federal Fluminense (UFF. Dez alunos do Curso de Especialização em Ortodontia da UFF identificaram pontos de referência sobre papel de acetato transparente e foram feitas medições das seguintes variáveis cefalométricas: ANB, FMIA, IMPA, FMA, ângulo interincisal, 1-NA (mm e ¯1-NB (mm. Em seguida, foram calculadas médias aritméticas, desvios-padrão e coeficientes de variância de cada variável para os dois pacientes. RESULTADOS E CONCLUSÃO: os valores das medições realizadas a partir de imagens em 3D apresentaram menor dispersão, sugerindo que essas imagens são mais confiáveis quanto à identificação de alguns pontos cefalométricos. Entretanto, como as imagens em 3D impressas utilizadas no presente estudo não permitiram a visualização de pontos intracranianos, torna-se necessário que softwares específicos sejam elaborados para que esse tipo de exame possa se tornar rotineiro na clínica ortodôntica.OBJECTIVE: To compare the reliability of two different methods used for viewing and identifying cephalometric landmarks, i.e., (a using conventional cephalometric radiographs, and (b using 2D and 3D images generated by Cone-Beam Computed Tomography. METHODS: The material consisted of lateral view 2D and 3D images obtained by Cone-Beam Computed Tomography printed on photo paper, and lateral cephalometric radiographs, taken in the same

  9. Intermodality comparison between 3D perfusion CT and 18F-FDG PET/CT imaging for predicting early tumor response in patients with liver metastasis after chemotherapy: Preliminary results of a prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Hyun [Department of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Se Hyung, E-mail: shkim7071@gmail.com [Department of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); The Institute of Radiation Medicine, Seoul National University Hospital, Seoul (Korea, Republic of); Im, Seock-Ah; Han, Sae-Won [Department of Internal Medicine, Seoul National University Hospital, Seoul (Korea, Republic of); Goo, Jin Mo [Department of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); The Institute of Radiation Medicine, Seoul National University Hospital, Seoul (Korea, Republic of); Willmann, Juergen K. [Department of Radiology and Molecular Imaging Program at Stanford, Stanford University School of Medicine, CA (United States); Lee, Eun Seong; Eo, Jae Seon; Paeng, Jin Chul [Department of Nuclear Medicine, Seoul National University Hospital, Seoul (Korea, Republic of); Han, Joon Koo; Choi, Byung Ihn [Department of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); The Institute of Radiation Medicine, Seoul National University Hospital, Seoul (Korea, Republic of)

    2012-11-15

    Objectives: To evaluate the feasibility of 3D perfusion CT for predicting early treatment response in patients with liver metastasis from colorectal cancer. Methods: Seventeen patients with colon cancer and liver metastasis were prospectively enroled to undergo perfusion CT and 18F-FDG-PET/CT before and after one-cycle of chemotherapy. Two radiologists and three nuclear medicine physicians measured various perfusion CT and PET/CT parameters, respectively from the largest hepatic metastasis. Baseline values and reduction rates of the parameters were compared between responders and nonresponders. Spearman correlation test was used to correlate perfusion CT and PET/CT parameters, using RECIST criteria as reference standard. Results: Nine patients responded to treatment, eight patients were nonresponders. Baseline SUV{sub mean30} on PET/CT, reduction rates of 30% metabolic volume and 30% lesion glycolysis (LG{sub 30}) on PET/CT and blood flow (BF) and flow extraction product (FEP) on perfusion CT after chemotherapy were significantly different between responders and nonresponders (P = 0.008-0.046). Reduction rates of BF (correlation coefficient = 0.630) and FEP (correlation coefficient = 0.578) significantly correlated with that of LG{sub 30} on PET/CT (P < 0.05). Conclusion: CT perfusion parameters including BF and FEP may be used as early predictors of tumor response in patients with liver metastasis from colorectal cancer.

  10. Diagnostic value of 3 D CT surface reconstruction in spinal fractures

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, S. [Department of Radiology, Univ. of Leipzig (Germany); Dietrich, K. [Department of Radiology, Univ. of Leipzig (Germany); Steinecke, R. [Department of Radiology, Univ. of Leipzig (Germany); Kloeppel, R. [Department of Radiology, Univ. of Leipzig (Germany); Schulz, H.G. [Department of Radiology, Univ. of Leipzig (Germany)

    1997-02-01

    Our purpose was to evaluate the diagnostic value of three-dimensional (3 D) CT surface reconstruction in spinal fractures in comparison with axial and reformatted images. A total of 50 patients with different CT-proven spinal fractures were analysed retrospectively. Based on axial scans and reformatted images, the spinal fractures were classified according to several classifications as Magerl for the thoraco-lumbar and lower cervical spine by one radiologist. Another radiologist performed 3 D CT surface reconstructions with the aim of characterizing the different types of spinal fractures. A third radiologist classified the 3 D CT surface reconstruction according to the Magerl classification. The results of the blinded reading process were compared. It was checked to see in which type and subgroup 3 D surface reconstructions were helpful. Readers one and two obtained the same results in the classification. The 3 D surface reconstruction did not yield any additional diagnostic information concerning type A and B injuries. Indeed, the full extent of the fracture could be easier recognized with axial and reformatted images in all cases. In 10 cases of C injuries, the dislocation of parts of vertebrae could be better recognized with the help of 3 D reconstructions. A 3 D CT surface reconstruction is only useful in rotational and shear vertebral injuries (Magerl type C injury). (orig.). With 4 figs., 1 tab.

  11. Applicability of 3D-CT facial reconstruction for forensic individual identification.

    Science.gov (United States)

    Rocha, Sara dos Santos; Ramos, Dalton Luiz; Cavalcanti, Marcelo de Gusmão Paraíso

    2003-01-01

    Computed tomography (CT) is used in several clinical dentistry applications even by axial slices and two and three-dimensional reconstructed images (2D-CT and 3D-CT). The purpose of the current study is to assess the precision of linear measurements made in 3D-CT using craniometric patterns for individual identification in Forensic Dentistry. Five cadaver heads were submitted to a spiral computed tomography using axial slices, and 3D-CT reconstructions were obtained by volume rendering technique with computer graphics tools. Ten (10) craniometric measurements were determined in 3D-CT images by two examiners independently, twice each, and the standard error of intra- and inter-examiner measurements was assessed. The results demonstrated a low standard error of those measurements, from 0.85% to 3.09%. In conclusion, the linear measurements obtained in osseous and soft tissue structures were considered to be precise in 3D-CT with high imaging quality and resolution.

  12. Applicability of 3D-CT facial reconstruction for forensic individual identification

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Sara dos Santos [Sao Paulo Univ., SP (Brazil). Odontologia Forense; Ramos, Dalton Luiz de Paula [Sao Paulo Univ., SP (Brazil). Dept. of Odontologia Social; Cavalcanti, Marcelo de Gusmao Paraiso [Sao Paulo Univ., SP (Brazil). Dept. de Radiologia

    2003-03-01

    Computed tomography (CT) is used in several clinical dentistry applications even by axial slices and two and three-dimensional reconstructed images (2D-CT and 3D-CT). The purpose of the current study is to assess the precision of linear measurements made in 3D-CT using cranio metric patterns for individual identification in Forensic Dentistry. Five cadaver heads were submitted to a spiral computed tomography using axial slices, and 3D-CT reconstructions were obtained by volume rendering technique with computer graphics tools. Ten (10) cranio metric measurements were determined in 3D-CT images by two examiners independently, twice each, and the standard error of intra- and inter-examiner measurements was assessed. The results demonstrated a low standard error of those measurements, from 0.85% to 3.09%. In conclusion, the linear measurements obtained in osseous and soft tissue structures were considered to be precise in 3D-CT with high imaging quality and resolution. (author)

  13. 3D Backscatter Imaging System

    Science.gov (United States)

    Turner, D. Clark (Inventor); Whitaker, Ross (Inventor)

    2016-01-01

    Systems and methods for imaging an object using backscattered radiation are described. The imaging system comprises both a radiation source for irradiating an object that is rotationally movable about the object, and a detector for detecting backscattered radiation from the object that can be disposed on substantially the same side of the object as the source and which can be rotationally movable about the object. The detector can be separated into multiple detector segments with each segment having a single line of sight projection through the object and so detects radiation along that line of sight. Thus, each detector segment can isolate the desired component of the backscattered radiation. By moving independently of each other about the object, the source and detector can collect multiple images of the object at different angles of rotation and generate a three dimensional reconstruction of the object. Other embodiments are described.

  14. Anatomical references for tibial sagittal alignment in total knee arthroplasty: A comparison of three anatomical axes based on 3D reconstructed CT images

    Institute of Scientific and Technical Information of China (English)

    SHAO Jun-jie; Thomas Parker Vail; WANG Qiao-jie; SHEN Hao; CHEN Yun-su; WANG Qi; JIANG Yao

    2013-01-01

    Background This study was designed to analyze three tibial axis reference lines including the anterior tibial cortex (ATC) line,the fibular line (FL),and the anatomical axis of tibia (AAT) line,to determine which line most closely parallels the mechanical axis (MA) of the tibia in the sagittal plane.The clinical relevance of the study is that through finding a reliable landmark on the leg,a surgeon may minimize posterior tibial slope measurement errors thereby and improving the technique for assuring proper alignment of total knee arthroplasty.Methods The material for this study included CT scans of the tibia from 85 consecutive patients and 168 knees (78 without osteoarthritis (OA) and 90 knees with OA).Measurements of the angles between the tibial mechanical axis and each of three reference lines in the sagittal plane were carried out using 3D imaging software.Results Mean angles of 168 knees were as follows:aMT (3.96±0.85)°,aMF (0.70±0.58)°,and aMA (1.40±0.66)°,(aMT:an angle between MA and ATC,aMF:an angle between MA and FL,aMA:an angle between MA and AAT.All abovementioned angles were measured in the sagittal plane of tibia) and the aMF was significantly smaller than the others (P <0.0001).The mean value of the medial tibial slope angle vs.the MA was (9.19±3.97)°,and this was significantly larger than the mean lateral slope angle of (6.62±4.23)° (P <0.0001).The difference between aMF without OA and with OA was not statistically significant (P=0.5015) and the association between the aMT and aMA was strong (r=0.82,P <0.01).Conclusions FL was more closely parallel to the MA of tibia,and more showed less variation between OA and nonOA controls than ATC and AAT lines.Furthermore,the amount of posterior slope in medial plateau was greater than that in lateral plateau.The findings of this analysis suggest that when using the anterior tibial cortex line as is commonly done with extramedullary tibial resection guides,the tibial resection should be sloped

  15. Comparison of physical quality assurance between Scanora 3D and 3D Accuitomo 80 dental CT scanners

    Directory of Open Access Journals (Sweden)

    Ahmed S. Ali

    2015-06-01

    Full Text Available Background: The use of cone beam computed tomography (CBCT in dentistry has proven to be useful in the diagnosis and treatment planning of several oral and maxillofacial diseases. The quality of the resulting image is dictated by many factors related to the patient, unit, and operator. Materials and methods: In this work, two dental CBCT units, namely Scanora 3D and 3D Accuitomo 80, were assessed and compared in terms of quantitative effective dose delivered to specific locations in a dosimetry phantom. Resolution and contrast were evaluated in only 3D Accuitomo 80 using special quality assurance phantoms. Results: Scanora 3D, with less radiation time, showed less dosing values compared to 3D Accuitomo 80 (mean 0.33 mSv, SD±0.16 vs. 0.18 mSv, SD±0.1. Using paired t-test, no significant difference was found in Accuitomo two scan sessions (p>0.05, while it was highly significant in Scanora (p>0.05. The modulation transfer function value (at 2 lp/mm, in both measurements, was found to be 4.4%. The contrast assessment of 3D Accuitomo 80 in the two measurements showed few differences, for example, the grayscale values were the same (SD=0 while the noise level was slightly different (SD=0 and 0.67, respectively. Conclusions: The radiation dose values in these two CBCT units are significantly less than those encountered in systemic CT scans. However, the dose seems to be affected more by changing the field of view rather than the voltage or amperage. The low doses were at the expense of the image quality produced, which was still acceptable. Although the spatial resolution and contrast were inferior to the medical images produced in systemic CT units, the present results recommend adopting CBCTs in maxillofacial imaging because of low radiation dose and adequate image quality.

  16. 3D thermal medical image visualization tool: Integration between MRI and thermographic images.

    Science.gov (United States)

    Abreu de Souza, Mauren; Chagas Paz, André Augusto; Sanches, Ionildo Jóse; Nohama, Percy; Gamba, Humberto Remigio

    2014-01-01

    Three-dimensional medical image reconstruction using different images modalities require registration techniques that are, in general, based on the stacking of 2D MRI/CT images slices. In this way, the integration of two different imaging modalities: anatomical (MRI/CT) and physiological information (infrared image), to generate a 3D thermal model, is a new methodology still under development. This paper presents a 3D THERMO interface that provides flexibility for the 3D visualization: it incorporates the DICOM parameters; different color scale palettes at the final 3D model; 3D visualization at different planes of sections; and a filtering option that provides better image visualization. To summarize, the 3D thermographc medical image visualization provides a realistic and precise medical tool. The merging of two different imaging modalities allows better quality and more fidelity, especially for medical applications in which the temperature changes are clinically significant.

  17. 3D-CT of the temporal bone area with high-speed processing

    Energy Technology Data Exchange (ETDEWEB)

    Hattori, Taku [Nagoya Univ. (Japan). Branch Hospital

    1994-12-01

    Three-dimentional (3D)-CT was introduced to represent abnormal findings in the temporal bone area utilizing a SOMATOM DRH CT scanner with accessory 3D reconstruction software and an exclusive high-speed 3D processing system, VOXEL FLINGER. In a patient with eosinophilic granuloma, a defect in the squamous part of the temporal bone was demonstrated suggesting exposure of the dura mater during surgery. In a patient with a normal ear, well-developed mastoid cavity, a part of the handle and the head of the malleus, the incudomalleal joint, the short limb, body and a part of the long limb of the incus and the round window niche were demonstrated. In a case of chronic otitis media, poorly developed mastoid cavity and a possible defect of the tip of the long limb of the incus were demonstrated, in contrast to the patient with the normal ear. 3D-CT yields objective and solid images which are useful for diagnosis, treatment planning and explanation of the pathology to patients and their family. To obtain convincing 3D images, physicians themselves have to choose exact rotation angles. It is not adequate to reconstruct original CT data using a CT computer with accessory 3D software whose processing capability is not good enough for this purpose. The conclusion is as follows: (1) it is necessary and effective to transfer original CT data into the memory of the exclusive high-speed 3D processing system and (2) process the data by the voxel memory method to establish a clinically valuable 3D-CT imaging system. (author).

  18. 3D ultrasound imaging for prosthesis fabrication and diagnostic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, A.K.; Bow, W.J.; Strong, D.S. [and others

    1995-06-01

    The fabrication of a prosthetic socket for a below-the-knee amputee requires knowledge of the underlying bone structure in order to provide pressure relief for sensitive areas and support for load bearing areas. The goal is to enable the residual limb to bear pressure with greater ease and utility. Conventional methods of prosthesis fabrication are based on limited knowledge about the patient`s underlying bone structure. A 3D ultrasound imaging system was developed at Sandia National Laboratories. The imaging system provides information about the location of the bones in the residual limb along with the shape of the skin surface. Computer assisted design (CAD) software can use this data to design prosthetic sockets for amputees. Ultrasound was selected as the imaging modality. A computer model was developed to analyze the effect of the various scanning parameters and to assist in the design of the overall system. The 3D ultrasound imaging system combines off-the-shelf technology for image capturing, custom hardware, and control and image processing software to generate two types of image data -- volumetric and planar. Both volumetric and planar images reveal definition of skin and bone geometry with planar images providing details on muscle fascial planes, muscle/fat interfaces, and blood vessel definition. The 3D ultrasound imaging system was tested on 9 unilateral below-the- knee amputees. Image data was acquired from both the sound limb and the residual limb. The imaging system was operated in both volumetric and planar formats. An x-ray CT (Computed Tomography) scan was performed on each amputee for comparison. Results of the test indicate beneficial use of ultrasound to generate databases for fabrication of prostheses at a lower cost and with better initial fit as compared to manually fabricated prostheses.

  19. 3D Reconstruction of NMR Images

    Directory of Open Access Journals (Sweden)

    Peter Izak

    2007-01-01

    Full Text Available This paper introduces experiment of 3D reconstruction NMR images scanned from magnetic resonance device. There are described methods which can be used for 3D reconstruction magnetic resonance images in biomedical application. The main idea is based on marching cubes algorithm. For this task was chosen sophistication method by program Vision Assistant, which is a part of program LabVIEW.

  20. Using cone-beam CT as a low-dose 3D imaging technique for the extremities: initial experience in 50 subjects

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Ambrose J.; Chang, Connie Y.; Palmer, William E. [Massachusetts General Hospital, Department of Radiology, Division of Musculoskeletal Imaging and Intervention, Boston, MA (United States); Thomas, Bijoy J. [Universal College of Medical Sciences, Department of Radiology, Bhairahawa (Nepal); MacMahon, Peter J. [Mater Misericordiae University Hospital, Department of Radiology, Dublin 7 (Ireland)

    2015-06-01

    To prospectively evaluate a dedicated extremity cone-beam CT (CBCT) scanner in cases with and without orthopedic hardware by (1) comparing its imaging duration and image quality to those of radiography and multidetector CT (MDCT) and (2) comparing its radiation dose to that of MDCT. Written informed consent was obtained for all subjects for this IRB-approved, HIPAA-compliant study. Fifty subjects with (1) fracture of small bones, (2) suspected intraarticular fracture, (3) fracture at the site of complex anatomy, or (4) a surgical site difficult to assess with radiography alone were recruited and scanned on an extremity CBCT scanner prior to FDA approval. Same-day radiographs were performed in all subjects. Some subjects also underwent MDCT within 1 month of CBCT. Imaging duration and image quality were compared between CBCT and radiographs. Imaging duration, effective radiation dose, and image quality were compared between CBCT and MDCT. Fifty-one CBCT scans were performed in 50 subjects. Average imaging duration was shorter for CBCT than radiographs (4.5 min vs. 6.6 min, P = 0.001, n = 51) and MDCT (7.6 min vs. 10.9 min, P = 0.01, n = 7). Average estimated effective radiation dose was less for CBCT than MDCT (0.04 mSv vs. 0.13 mSv, P = 0.02, n = 7). CBCT images yielded more diagnostic information than radiographs in 23/51 cases and more diagnostic information than MDCT in 1/7 cases, although radiographs were superior for detecting hardware complications. CBCT performs high-resolution imaging of the extremities using less imaging time than radiographs and MDCT and lower radiation dose than MDCT. (orig.)

  1. 3D imaging in forensic odontology.

    Science.gov (United States)

    Evans, Sam; Jones, Carl; Plassmann, Peter

    2010-06-16

    This paper describes the investigation of a new 3D capture method for acquiring and subsequent forensic analysis of bite mark injuries on human skin. When documenting bite marks with standard 2D cameras errors in photographic technique can occur if best practice is not followed. Subsequent forensic analysis of the mark is problematic when a 3D structure is recorded into a 2D space. Although strict guidelines (BAFO) exist, these are time-consuming to follow and, due to their complexity, may produce errors. A 3D image capture and processing system might avoid the problems resulting from the 2D reduction process, simplifying the guidelines and reducing errors. Proposed Solution: a series of experiments are described in this paper to demonstrate that the potential of a 3D system might produce suitable results. The experiments tested precision and accuracy of the traditional 2D and 3D methods. A 3D image capture device minimises the amount of angular distortion, therefore such a system has the potential to create more robust forensic evidence for use in courts. A first set of experiments tested and demonstrated which method of forensic analysis creates the least amount of intra-operator error. A second set tested and demonstrated which method of image capture creates the least amount of inter-operator error and visual distortion. In a third set the effects of angular distortion on 2D and 3D methods of image capture were evaluated.

  2. Esophagus Segmentation from 3D CT Data Using Skeleton Prior-Based Graph Cut

    Directory of Open Access Journals (Sweden)

    Damien Grosgeorge

    2013-01-01

    Full Text Available The segmentation of organs at risk in CT volumes is a prerequisite for radiotherapy treatment planning. In this paper, we focus on esophagus segmentation, a challenging application since the wall of the esophagus, made of muscle tissue, has very low contrast in CT images. We propose in this paper an original method to segment in thoracic CT scans the 3D esophagus using a skeleton-shape model to guide the segmentation. Our method is composed of two steps: a 3D segmentation by graph cut with skeleton prior, followed by a 2D propagation. Our method yields encouraging results over 6 patients.

  3. Multiplane 3D superresolution optical fluctuation imaging

    CERN Document Server

    Geissbuehler, Stefan; Godinat, Aurélien; Bocchio, Noelia L; Dubikovskaya, Elena A; Lasser, Theo; Leutenegger, Marcel

    2013-01-01

    By switching fluorophores on and off in either a deterministic or a stochastic manner, superresolution microscopy has enabled the imaging of biological structures at resolutions well beyond the diffraction limit. Superresolution optical fluctuation imaging (SOFI) provides an elegant way of overcoming the diffraction limit in all three spatial dimensions by computing higher-order cumulants of image sequences of blinking fluorophores acquired with a conventional widefield microscope. So far, three-dimensional (3D) SOFI has only been demonstrated by sequential imaging of multiple depth positions. Here we introduce a versatile imaging scheme which allows for the simultaneous acquisition of multiple focal planes. Using 3D cross-cumulants, we show that the depth sampling can be increased. Consequently, the simultaneous acquisition of multiple focal planes reduces the acquisition time and hence the photo-bleaching of fluorescent markers. We demonstrate multiplane 3D SOFI by imaging the mitochondria network in fixed ...

  4. Nonlaser-based 3D surface imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Shin-yee; Johnson, R.K.; Sherwood, R.J. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    3D surface imaging refers to methods that generate a 3D surface representation of objects of a scene under viewing. Laser-based 3D surface imaging systems are commonly used in manufacturing, robotics and biomedical research. Although laser-based systems provide satisfactory solutions for most applications, there are situations where non laser-based approaches are preferred. The issues that make alternative methods sometimes more attractive are: (1) real-time data capturing, (2) eye-safety, (3) portability, and (4) work distance. The focus of this presentation is on generating a 3D surface from multiple 2D projected images using CCD cameras, without a laser light source. Two methods are presented: stereo vision and depth-from-focus. Their applications are described.

  5. 2D-3D image registration in diagnostic and interventional X-Ray imaging

    NARCIS (Netherlands)

    Bom, I.M.J. van der

    2010-01-01

    Clinical procedures that are conventionally guided by 2D x-ray imaging, may benefit from the additional spatial information provided by 3D image data. For instance, guidance of minimally invasive procedures with CT or MRI data provides 3D spatial information and visualization of structures that are

  6. 3D integral imaging with optical processing

    Science.gov (United States)

    Martínez-Corral, Manuel; Martínez-Cuenca, Raúl; Saavedra, Genaro; Javidi, Bahram

    2008-04-01

    Integral imaging (InI) systems are imaging devices that provide auto-stereoscopic images of 3D intensity objects. Since the birth of this new technology, InI systems have faced satisfactorily many of their initial drawbacks. Basically, two kind of procedures have been used: digital and optical procedures. The "3D Imaging and Display Group" at the University of Valencia, with the essential collaboration of Prof. Javidi, has centered its efforts in the 3D InI with optical processing. Among other achievements, our Group has proposed the annular amplitude modulation for enlargement of the depth of field, dynamic focusing for reduction of the facet-braiding effect, or the TRES and MATRES devices to enlarge the viewing angle.

  7. Structured light field 3D imaging.

    Science.gov (United States)

    Cai, Zewei; Liu, Xiaoli; Peng, Xiang; Yin, Yongkai; Li, Ameng; Wu, Jiachen; Gao, Bruce Z

    2016-09-05

    In this paper, we propose a method by means of light field imaging under structured illumination to deal with high dynamic range 3D imaging. Fringe patterns are projected onto a scene and modulated by the scene depth then a structured light field is detected using light field recording devices. The structured light field contains information about ray direction and phase-encoded depth, via which the scene depth can be estimated from different directions. The multidirectional depth estimation can achieve high dynamic 3D imaging effectively. We analyzed and derived the phase-depth mapping in the structured light field and then proposed a flexible ray-based calibration approach to determine the independent mapping coefficients for each ray. Experimental results demonstrated the validity of the proposed method to perform high-quality 3D imaging for highly and lowly reflective surfaces.

  8. SU-E-T-294: Simulations to Investigate the Feasibility of ‘dry’ Optical-CT Imaging for 3D Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Chisholm, K [Duke University, Durham, NC (United States); Rankine, L [Washington University, Saint Louis, MO (United States); Oldham, M [Duke University Medical Center, Durham, NC (United States)

    2014-06-01

    Purpose: To perform simulations investigating the feasibility of “dry” optical-CT, and determine optimal design and scanning parameters for a novel dry tank telecentric optical-CT 3D dosimetry system. Such a system would have important advantages in terms of practical convenience and reduced cost. Methods: A Matlab based ray-tracing simulation platform, ScanSim, was used to model a telecentric system with a polyurethane dry tank, cylindrical dosimeter, and surrounding fluid. This program's capabilities were expanded for the geometry and physics of dry scanning. To categorize the effects of refractive index (RI) mismatches, simulations were run for several dosimeter (RI = 1.5−1.48) and fluid (RI = 1.55−1.33) combinations. Additional simulations examined the effect of increasing gap size (1–5mm) between the dosimeter and tank wall, and of changing the telecentric lens tolerance (0.5°−5°). The evaluation metric is the usable radius; the distance from the dosimeter center where the measured and true doses differ by less than 2%. Results: As the tank/dosimeter RI mismatch increases from 0–0.02, the usable radius decreases from 97.6% to 50.2%. The fluid RI for matching is lower than either the tank or dosimeter RI. Changing gap sizes has drastic effects on the usable radius, requiring more closely matched fluid at large gap sizes. Increasing the telecentric tolerance through a range from 0.5°–5.0° improved the usable radius for every combination of media. Conclusion: Dry optical-CT with telecentric lenses is feasible when the dosimeter and tank RIs are closely matched (<0.01 difference), or when data in the periphery is not required. The ScanSim tool proved very useful in situations when the tank and dosimeter have slight differences in RI by enabling estimation of the optimal choice of RI of the small amount of fluid still required. Some spoiling of the telecentric beam and increasing the tolerance helps recover the usable radius.

  9. Development of CT and 3D-CT Using Flat Panel Detector Based Real-Time Digital Radiography System

    Science.gov (United States)

    Ravindran, V. R.; Sreelakshmi, C.; Vibin, Vibin

    2008-09-01

    The application of Digital Radiography in the Nondestructive Evaluation (NDE) of space vehicle components is a recent development in India. A Real-time DR system based on amorphous silicon Flat Panel Detector has been developed for the NDE of solid rocket motors at Rocket Propellant Plant of VSSC in a few years back. The technique has been successfully established for the nondestructive evaluation of solid rocket motors. The DR images recorded for a few solid rocket specimens are presented in the paper. The Real-time DR system is capable of generating sufficient digital X-ray image data with object rotation for the CT image reconstruction. In this paper the indigenous development of CT imaging based on the Realtime DR system for solid rocket motor is presented. Studies are also carried out to generate 3D-CT image from a set of adjacent CT images of the rocket motor. The capability of revealing the spatial location and characterisation of defect is demonstrated by the CT and 3D-CT images generated.

  10. Heat Equation to 3D Image Segmentation

    Directory of Open Access Journals (Sweden)

    Nikolay Sirakov

    2006-04-01

    Full Text Available This paper presents a new approach, capable of 3D image segmentation and objects' surface reconstruction. The main advantages of the method are: large capture range; quick segmentation of a 3D scene/image to regions; multiple 3D objects reconstruction. The method uses centripetal force and penalty function to segment the entire 3D scene/image to regions containing a single 3D object. Each region is inscribed in a convex, smooth closed surface, which defines a centripetal force. Then the surface is evolved by the geometric heat differential equation toward the force's direction. The penalty function is defined to stop evolvement of those surface patches, whose normal vectors encountered object's surface. On the base of the theoretical model Forward Difference Algorithm was developed and coded by Mathematica. Stability convergence condition, truncation error and calculation complexity of the algorithm are determined. The obtained results, advantages and disadvantages of the method are discussed at the end of this paper.

  11. Multimodal 3D PET/CT system for bronchoscopic procedure planning

    Science.gov (United States)

    Cheirsilp, Ronnarit; Higgins, William E.

    2013-02-01

    Integrated positron emission tomography (PET) / computed-tomography (CT) scanners give 3D multimodal data sets of the chest. Such data sets offer the potential for more complete and specific identification of suspect lesions and lymph nodes for lung-cancer assessment. This in turn enables better planning of staging bronchoscopies. The richness of the data, however, makes the visualization and planning process difficult. We present an integrated multimodal 3D PET/CT system that enables efficient region identification and bronchoscopic procedure planning. The system first invokes a series of automated 3D image-processing methods that construct a 3D chest model. Next, the user interacts with a set of interactive multimodal graphical tools that facilitate procedure planning for specific regions of interest (ROIs): 1) an interactive region candidate list that enables efficient ROI viewing in all tools; 2) a virtual PET-CT bronchoscopy rendering with SUV quantitative visualization to give a "fly through" endoluminal view of prospective ROIs; 3) transverse, sagittal, coronal multi-planar reformatted (MPR) views of the raw CT, PET, and fused CT-PET data; and 4) interactive multimodal volume/surface rendering to give a 3D perspective of the anatomy and candidate ROIs. In addition the ROI selection process is driven by a semi-automatic multimodal method for region identification. In this way, the system provides both global and local information to facilitate more specific ROI identification and procedure planning. We present results to illustrate the system's function and performance.

  12. Micromachined Ultrasonic Transducers for 3-D Imaging

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lehrmann

    Real-time ultrasound imaging is a widely used technique in medical diagnostics. Recently, ultrasound systems offering real-time imaging in 3-D has emerged. However, the high complexity of the transducer probes and the considerable increase in data to be processed compared to conventional 2-D...... ultrasound imaging results in expensive systems, which limits the more wide-spread use and clinical development of volumetric ultrasound. The main goal of this thesis is to demonstrate new transducer technologies that can achieve real-time volumetric ultrasound imaging without the complexity and cost...... of state-of-the-art 3-D ultrasound systems. The focus is on row-column addressed transducer arrays. This previously sparsely investigated addressing scheme offers a highly reduced number of transducer elements, resulting in reduced transducer manufacturing costs and data processing. To produce...

  13. A statistical description of 3D lung texture from CT data

    Science.gov (United States)

    Chaisaowong, Kraisorn; Paul, Andreas

    2015-03-01

    A method was described to create a statistical description of 3D lung texture from CT data. The second order statistics, i.e. the gray level co-occurrence matrix (GLCM), has been applied to characterize texture of lung by defining the joint probability distribution of pixel pairs. The required GLCM was extended to three-dimensional image regions to deal with CT volume data. For a fine-scale lung segmentation, both the 3D GLCM of lung and thorax without lung are required. Once the co-occurrence densities are measured, the 3D models of the joint probability density function for each describing direction of involving voxel pairs and for each class (lung or thorax) are estimated using mixture of Gaussians through the expectation-maximization algorithm. This leads to a feature space that describes the 3D lung texture.

  14. 3D Membrane Imaging and Porosity Visualization

    KAUST Repository

    Sundaramoorthi, Ganesh

    2016-03-03

    Ultrafiltration asymmetric porous membranes were imaged by two microscopy methods, which allow 3D reconstruction: Focused Ion Beam and Serial Block Face Scanning Electron Microscopy. A new algorithm was proposed to evaluate porosity and average pore size in different layers orthogonal and parallel to the membrane surface. The 3D-reconstruction enabled additionally the visualization of pore interconnectivity in different parts of the membrane. The method was demonstrated for a block copolymer porous membrane and can be extended to other membranes with application in ultrafiltration, supports for forward osmosis, etc, offering a complete view of the transport paths in the membrane.

  15. Aortic valve and ascending aortic root modeling from 3D and 3D+t CT

    Science.gov (United States)

    Grbic, Saša; Ionasec, Razvan I.; Zäuner, Dominik; Zheng, Yefeng; Georgescu, Bogdan; Comaniciu, Dorin

    2010-02-01

    Aortic valve disorders are the most frequent form of valvular heart disorders (VHD) affecting nearly 3% of the global population. A large fraction among them are aortic root diseases, such as aortic root aneurysm, often requiring surgical procedures (valve-sparing) as a treatment. Visual non-invasive assessment techniques could assist during pre-selection of adequate patients, planning procedures and afterward evaluation of the same. However state of the art approaches try to model a rather short part of the aortic root, insufficient to assist the physician during intervention planning. In this paper we propose a novel approach for morphological and functional quantification of both the aortic valve and the ascending aortic root. A novel physiological shape model is introduced, consisting of the aortic valve root, leaflets and the ascending aortic root. The model parameters are hierarchically estimated using robust and fast learning-based methods. Experiments performed on 63 CT sequences (630 Volumes) and 20 single phase CT volumes demonstrated an accuracy of 1.45mm and an performance of 30 seconds (3D+t) for this approach. To the best of our knowledge this is the first time a complete model of the aortic valve (including leaflets) and the ascending aortic root, estimated from CT, has been proposed.

  16. 基于3D-CT与4D-CT勾画保留乳房手术后全乳靶区的比较研究%Comparison study of clinical target volumes of whole breast after breast-conserving surgery based on three-dimensional CT and four-dimensional CT images

    Institute of Scientific and Technical Information of China (English)

    王素贞; 李建彬; 张英杰; 王玮; 李奉祥; 徐敏; 邵倩; 范廷勇; 刘同海

    2012-01-01

    Objective To study the differences of the clinical target volume ( CTV) based on three-dimensional CT (3D-CT) and four-dimensional CT (4D-CT) of the whole breast after breast-conserving surgery. Methods Thirteen patients after breast-conserving surgery underwent 3D-CT simulation scans followed by 4D-CT simulation scans of the thorax during free breathing. During 4D-CT scanning, real-time position management ( RPM ) system simultaneously recorded the respiratory signals. The CT images with respiratory signal data were reconstructed and sorted into 10 phase groups in a respiratory cycle. Data sets for 3D-CT and 4D-CT scans were then transferred to Eclipse treatment planning software. The 4D-CT image of the end-inhalation phase (TO) served as a background and the other nine phases ( T10 , T20 , T30··· T90 ) , maximum intensity projection ( MIP ) image and 3D-CT image were registered. The CTV were manually delineated on the registered images of the 3D-CT, TO, middle-exhalation (T20) , end-exhalation (T50) , MIP images based on the TO of 4D-CT by a radiation oncologist at two different times. Then the CTV3D , CTV0 , CTV10··· CTVMIP were delineated and defined on the 3D-CT, TO, T10···MIP images based on the TO images of 4D-CT by the same radiation oncologist. All the CTVs ( CTV0 , CTV10 , CTV10··· CTV90) delineated on the 10 phases of the 4D-CT images were fused into an internal clinical target volume (ICTV). The TO , T20 , T50 , MIP images were selected from the CTVs of the 4D-CT to compare with the 3D-CT image. The differences of the targets delineated on the same images by the same radiation oncologist at different times were compared. The volumes of the CTVS, the matching index ( MI) and the degree of inclusion ( DI) were compared respectively. Results There was no difference in the CTV delineated by the same oncologist no matter based on 3D-CT or 4D-CT( P>0. 050). The CTVs volumes of ten phases in 4D-CT were not impacted by respiratory movement( P>0. 05

  17. Automated curved planar reformation of 3D spine images

    Energy Technology Data Exchange (ETDEWEB)

    Vrtovec, Tomaz; Likar, Bostjan; Pernus, Franjo [University of Ljubljana, Faculty of Electrical Engineering, Trzaska 25, SI-1000 Ljubljana (Slovenia)

    2005-10-07

    Traditional techniques for visualizing anatomical structures are based on planar cross-sections from volume images, such as images obtained by computed tomography (CT) or magnetic resonance imaging (MRI). However, planar cross-sections taken in the coordinate system of the 3D image often do not provide sufficient or qualitative enough diagnostic information, because planar cross-sections cannot follow curved anatomical structures (e.g. arteries, colon, spine, etc). Therefore, not all of the important details can be shown simultaneously in any planar cross-section. To overcome this problem, reformatted images in the coordinate system of the inspected structure must be created. This operation is usually referred to as curved planar reformation (CPR). In this paper we propose an automated method for CPR of 3D spine images, which is based on the image transformation from the standard image-based to a novel spine-based coordinate system. The axes of the proposed spine-based coordinate system are determined on the curve that represents the vertebral column, and the rotation of the vertebrae around the spine curve, both of which are described by polynomial models. The optimal polynomial parameters are obtained in an image analysis based optimization framework. The proposed method was qualitatively and quantitatively evaluated on five CT spine images. The method performed well on both normal and pathological cases and was consistent with manually obtained ground truth data. The proposed spine-based CPR benefits from reduced structural complexity in favour of improved feature perception of the spine. The reformatted images are diagnostically valuable and enable easier navigation, manipulation and orientation in 3D space. Moreover, reformatted images may prove useful for segmentation and other image analysis tasks.

  18. High resolution 3-D wavelength diversity imaging

    Science.gov (United States)

    Farhat, N. H.

    1981-09-01

    A physical optics, vector formulation of microwave imaging of perfectly conducting objects by wavelength and polarization diversity is presented. The results provide the theoretical basis for optimal data acquisition and three-dimensional tomographic image retrieval procedures. These include: (a) the selection of highly thinned (sparse) receiving array arrangements capable of collecting large amounts of information about remote scattering objects in a cost effective manner and (b) techniques for 3-D tomographic image reconstruction and display in which polarization diversity data is fully accounted for. Data acquisition employing a highly attractive AMTDR (Amplitude Modulated Target Derived Reference) technique is discussed and demonstrated by computer simulation. Equipment configuration for the implementation of the AMTDR technique is also given together with a measurement configuration for the implementation of wavelength diversity imaging in a roof experiment aimed at imaging a passing aircraft. Extension of the theory presented to 3-D tomographic imaging of passive noise emitting objects by spectrally selective far field cross-correlation measurements is also given. Finally several refinements made in our anechoic-chamber measurement system are shown to yield drastic improvement in performance and retrieved image quality.

  19. 3-D Reconstruction From 2-D Radiographic Images and Its Application to Clinical Veterinary Medicine

    Science.gov (United States)

    Hamamoto, Kazuhiko; Sato, Motoyoshi

    3D imaging technique is very important and indispensable in diagnosis. The main stream of the technique is one in which 3D image is reconstructed from a set of slice images, such as X-ray CT and MRI. However, these systems require large space and high costs. On the other hand, a low cost and small size 3D imaging system is needed in clinical veterinary medicine, for example, in the case of diagnosis in X-ray car or pasture area. We propose a novel 3D imaging technique using 2-D X-ray radiographic images. This system can be realized by cheaper system than X-ray CT and enables to get 3D image in X-ray car or portable X-ray equipment. In this paper, a 3D visualization technique from 2-D radiographic images is proposed and several reconstructions are shown. These reconstructions are evaluated by veterinarians.

  20. The European Society of Therapeutic Radiology and Oncology-European Institute of Radiotherapy (ESTRO-EIR) report on 3D CT-based in-room image guidance systems: a practical and technical review and guide.

    Science.gov (United States)

    Korreman, Stine; Rasch, Coen; McNair, Helen; Verellen, Dirk; Oelfke, Uwe; Maingon, Philippe; Mijnheer, Ben; Khoo, Vincent

    2010-02-01

    The past decade has provided many technological advances in radiotherapy. The European Institute of Radiotherapy (EIR) was established by the European Society of Therapeutic Radiology and Oncology (ESTRO) to provide current consensus statement with evidence-based and pragmatic guidelines on topics of practical relevance for radiation oncology. This report focuses primarily on 3D CT-based in-room image guidance (3DCT-IGRT) systems. It will provide an overview and current standing of 3DCT-IGRT systems addressing the rationale, objectives, principles, applications, and process pathways, both clinical and technical for treatment delivery and quality assurance. These are reviewed for four categories of solutions; kV CT and kV CBCT (cone-beam CT) as well as MV CT and MV CBCT. It will also provide a framework and checklist to consider the capability and functionality of these systems as well as the resources needed for implementation. Two different but typical clinical cases (tonsillar and prostate cancer) using 3DCT-IGRT are illustrated with workflow processes via feedback questionnaires from several large clinical centres currently utilizing these systems. The feedback from these clinical centres demonstrates a wide variability based on local practices. This report whilst comprehensive is not exhaustive as this area of development remains a very active field for research and development. However, it should serve as a practical guide and framework for all professional groups within the field, focussed on clinicians, physicists and radiation therapy technologists interested in IGRT.

  1. Usefulness of 3D-CT angiography using multislice CT for diagnosing cardiovascular anomalies in infants

    Energy Technology Data Exchange (ETDEWEB)

    Kani, Hiroyuki; Matsuki, Mitsuru; Masuda, Kiyohiro; Narabayashi, Isamu; Katayama, Hiroshi; Mori, Yasuhiko; Tamai, Hiroshi [Osaka Medical Coll., Takatsuki (Japan)

    2003-05-01

    We compared three-dimensional computed tomographic angiography using multislice CT (3D-CTA) with echocardiography and angiography in terms of usefulness in the diagnosis of 13 infants with cardiovascular anomalies. 3D-CTA clearly depicted stenoses of the pulmonary artery and vein, and coarctation of the aorta in some cases, which could not be revealed by echocardiography and angiography. Moreover, it provided objectively more information on vascular morphologic characteristics and 3D anatomic relations than echocardiography and angiography. 3D-CTA is a noninvasive and convenient diagnostic technique for cardiovascular anomalies in infants. (author)

  2. 3D strain measurement in soft tissue: demonstration of a novel inverse finite element model algorithm on MicroCT images of a tissue phantom exposed to negative pressure wound therapy.

    Science.gov (United States)

    Wilkes, R; Zhao, Y; Cunningham, K; Kieswetter, K; Haridas, B

    2009-07-01

    This study describes a novel system for acquiring the 3D strain field in soft tissue at sub-millimeter spatial resolution during negative pressure wound therapy (NPWT). Recent research in advanced wound treatment modalities theorizes that microdeformations induced by the application of sub-atmospheric (negative) pressure through V.A.C. GranuFoam Dressing, a reticulated open-cell polyurethane foam (ROCF), is instrumental in regulating the mechanobiology of granulation tissue formation [Saxena, V., Hwang, C.W., Huang, S., Eichbaum, Q., Ingber, D., Orgill, D.P., 2004. Vacuum-assisted closure: Microdeformations of wounds and cell proliferation. Plast. Reconstr. Surg. 114, 1086-1096]. While the clinical response is unequivocal, measurement of deformations at the wound-dressing interface has not been possible due to the inaccessibility of the wound tissue beneath the sealed dressing. Here we describe the development of a bench-test wound model for microcomputed tomography (microCT) imaging of deformation induced by NPWT and an algorithm set for quantifying the 3D strain field at sub-millimeter resolution. Microdeformations induced in the tissue phantom revealed average tensile strains of 18%-23% at sub-atmospheric pressures of -50 to -200 mmHg (-6.7 to -26.7 kPa). The compressive strains (22%-24%) and shear strains (20%-23%) correlate with 2D FEM studies of microdeformational wound therapy in the reference cited above. We anticipate that strain signals quantified using this system can then be used in future research aimed at correlating the effects of mechanical loading on the phenotypic expression of dermal fibroblasts in acute and chronic ulcer models. Furthermore, the method developed here can be applied to continuum deformation analysis in other contexts, such as 3D cell culture via confocal microscopy, full scale CT and MRI imaging, and in machine vision.

  3. 基于3D-CT、4D-CT和锥形束CT定义的非小细胞肺癌内靶区比较%Comparison of internal target volumes defined on three-dimensional CT, four-dimensional CT and cone-beam CT images of non-small-cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    李奉祥; 李建彬; 马志芳; 张英杰; 邢军; 戚焕鹏; 尚东平; 余宁莎

    2014-01-01

    Objective To compare positional and volumetric differences between internal target volumes defined on three-dimensional CT (3D-CT),four-dimensional CT (4D-CT) and cone-beam CT (CBCT) images of non-small-cell lung cancer.Methods Thirty-one patients with NSCLC sequentially underwent 3D-CT and 4D-CT simulation scans of the thorax during free breathing.A 3D conformal treatment plan was created based on 3D-CT.The CBCT images were obtained in the first fraction and registered to the planning CT using the bony anatomy registration.All target volumes were contoured with the same protocol by a radiation oncologist.GTVs were contoured based on 3D-CT,maximum intensity projection (MIP) of 4D-CT and CBCT.CTV3D,ITVMIPand ITVCBCTWere defined with a margin of 7 mm accounting for microscopic disease.ITV10mm and ITV5 mm were defined based on CTV3D.ITV10 mm with a margin of 5 mm in LR,AP directions and 10 mm in CC direction,while ITV5 mm with an isotropic internal margin (IM) of 5 mm.The differences in the position,size,Dice's similarity coefficient (DSC) and inclusion relation of different volumes were compared.Results The median size ratio of ITV10 mm,ITV5mm,ITVMIPto ITVCBCTwere 2.33,1.88,1.03 respectively for tumors in the upper lobe and 2.13,1.76,1.10 respectively for tumors in the middle-lower lobe.The median DSC of ITVMIP and ITVCBCT(0.83) was greater than that of ITV10 mm and ITVcBcT (0.6) and ITV5 mm and ITVCBCT (0.66) for all patients (Z =-4.86,-4.86,P < 0.05).The median percentages of ITVCBCT not included in ITV10 mm,ITV5 mm,ITVMIPwere 0.10%,1.63% and 15.21% respectively,while the median percentage of ITV10mm,ITV5mm,ITVMIP,not included in ITVCBCT were 57.08%,48.89% and 20.04%,respectively.The median percentage of ITVCBCT not included in ITV5 mm was 1.24% for tumors in the upper lobe and 5.8% for tumors in the middle-lower lobe.Conclusions The individual ITV based on 4D-CT can't encompass the ITV based on CBCT effectively.The use of the ITV derived from 4

  4. Thoracic cavity definition for 3D PET/CT analysis and visualization.

    Science.gov (United States)

    Cheirsilp, Ronnarit; Bascom, Rebecca; Allen, Thomas W; Higgins, William E

    2015-07-01

    X-ray computed tomography (CT) and positron emission tomography (PET) serve as the standard imaging modalities for lung-cancer management. CT gives anatomical details on diagnostic regions of interest (ROIs), while PET gives highly specific functional information. During the lung-cancer management process, a patient receives a co-registered whole-body PET/CT scan pair and a dedicated high-resolution chest CT scan. With these data, multimodal PET/CT ROI information can be gleaned to facilitate disease management. Effective image segmentation of the thoracic cavity, however, is needed to focus attention on the central chest. We present an automatic method for thoracic cavity segmentation from 3D CT scans. We then demonstrate how the method facilitates 3D ROI localization and visualization in patient multimodal imaging studies. Our segmentation method draws upon digital topological and morphological operations, active-contour analysis, and key organ landmarks. Using a large patient database, the method showed high agreement to ground-truth regions, with a mean coverage=99.2% and leakage=0.52%. Furthermore, it enabled extremely fast computation. For PET/CT lesion analysis, the segmentation method reduced ROI search space by 97.7% for a whole-body scan, or nearly 3 times greater than that achieved by a lung mask. Despite this reduction, we achieved 100% true-positive ROI detection, while also reducing the false-positive (FP) detection rate by >5 times over that achieved with a lung mask. Finally, the method greatly improved PET/CT visualization by eliminating false PET-avid obscurations arising from the heart, bones, and liver. In particular, PET MIP views and fused PET/CT renderings depicted unprecedented clarity of the lesions and neighboring anatomical structures truly relevant to lung-cancer assessment.

  5. 3-D Reconstruction From Satellite Images

    DEFF Research Database (Denmark)

    Denver, Troelz

    1999-01-01

    The aim of this project has been to implement a software system, that is able to create a 3-D reconstruction from two or more 2-D photographic images made from different positions. The height is determined from the disparity difference of the images. The general purpose of the system is mapping...... of planetary surfaces, but other purposes is considered as well. The system performance is measured with respect to the precision and the time consumption.The reconstruction process is divided into four major areas: Acquisition, calibration, matching/reconstruction and presentation. Each of these areas...... are treated individually. A detailed treatment of various lens distortions is required, in order to correct for these problems. This subject is included in the acquisition part. In the calibration part, the perspective distortion is removed from the images. Most attention has been paid to the matching problem...

  6. Microstructure analysis of the secondary pulmonary lobules by 3D synchrotron radiation CT

    Science.gov (United States)

    Fukuoka, Y.; Kawata, Y.; Niki, N.; Umetani, K.; Nakano, Y.; Ohmatsu, H.; Moriyama, N.; Itoh, H.

    2014-03-01

    Recognition of abnormalities related to the lobular anatomy has become increasingly important in the diagnosis and differential diagnosis of lung abnormalities at clinical routines of CT examinations. This paper aims a 3-D microstructural analysis of the pulmonary acinus with isotropic spatial resolution in the range of several micrometers by using micro CT. Previously, we demonstrated the ability of synchrotron radiation micro CT (SRμCT) using offset scan mode in microstructural analysis of the whole part of the secondary pulmonary lobule. In this paper, we present a semiautomatic method to segment the acinar and subacinar airspaces from the secondary pulmonary lobule and to track small vessels running inside alveolar walls in human acinus imaged by the SRμCT. The method beains with and segmentation of the tissues such as pleural surface, interlobular septa, alveola wall, or vessel using a threshold technique and 3-D connected component analysis. 3-D air space are then conustructed separated by tissues and represented branching patterns of airways and airspaces distal to the terminal bronchiole. A graph-partitioning approach isolated acini whose stems are interactively defined as the terminal bronchiole in the secondary pulmonary lobule. Finally, we performed vessel tracking using a non-linear sate space which captures both smoothness of the trajectories and intensity coherence along vessel orientations. Results demonstrate that the proposed method can extract several acinar airspaces from the 3-D SRμCT image of secondary pulmonary lobule and that the extracted acinar airspace enable an accurate quantitative description of the anatomy of the human acinus for interpretation of the basic unit of pulmonary structure and function.

  7. Visualization of postoperative anterior cruciate ligament reconstruction bone tunnels: Reliability of standard radiographs, CT scans, and 3D virtual reality images

    NARCIS (Netherlands)

    D.E. Meuffels (Duncan); J.W. Potters (Jan Willem); A.H.J. Koning (Anton); C.H. Brown Jr Jr. (Charles); J.A.N. Verhaar (Jan); M. Reijman (Max)

    2011-01-01

    textabstractBackground and purpose: Non-anatomic bone tunnel placement is the most common cause of a failed ACL reconstruction. Accurate and reproducible methods to visualize and document bone tunnel placement are therefore important. We evaluated the reliability of standard radiographs, CT scans, a

  8. Dynamic 3D computed tomography scanner for vascular imaging

    Science.gov (United States)

    Lee, Mark K.; Holdsworth, David W.; Fenster, Aaron

    2000-04-01

    A 3D dynamic computed-tomography (CT) scanner was developed for imaging objects undergoing periodic motion. The scanner system has high spatial and sufficient temporal resolution to produce quantitative tomographic/volume images of objects such as excised arterial samples perfused under physiological pressure conditions and enables the measurements of the local dynamic elastic modulus (Edyn) of the arteries in the axial and longitudinal directions. The system was comprised of a high resolution modified x-ray image intensifier (XRII) based computed tomographic system and a computer-controlled cardiac flow simulator. A standard NTSC CCD camera with a macro lens was coupled to the electro-optically zoomed XRII to acquire dynamic volumetric images. Through prospective cardiac gating and computer synchronized control, a time-resolved sequence of 20 mm thick high resolution volume images of porcine aortic specimens during one simulated cardiac cycle were obtained. Performance evaluation of the scanners illustrated that tomographic images can be obtained with resolution as high as 3.2 mm-1 with only a 9% decrease in the resolution for objects moving at velocities of 1 cm/s in 2D mode and static spatial resolution of 3.55 mm-1 with only a 14% decrease in the resolution in 3D mode for objects moving at a velocity of 10 cm/s. Application of the system for imaging of intact excised arterial specimens under simulated physiological flow/pressure conditions enabled measurements of the Edyn of the arteries with a precision of +/- kPa for the 3D scanner. Evaluation of the Edyn in the axial and longitudinal direction produced values of 428 +/- 35 kPa and 728 +/- 71 kPa, demonstrating the isotropic and homogeneous viscoelastic nature of the vascular specimens. These values obtained from the Dynamic CT systems were not statistically different (p less than 0.05) from the values obtained by standard uniaxial tensile testing and volumetric measurements.

  9. The quantification of glenoid bone loss in anterior shoulder instability; MR-arthro compared to 3D-CT

    Energy Technology Data Exchange (ETDEWEB)

    Markenstein, Jeroen E. [Onze Lieve Vrouwe Gasthuis, Department of Orthopedic Surgery, Postbox 95500, Amsterdam (Netherlands); Jaspars, Kjell C.C.J. [Van Weel-Bethesda Ziekenhuis, Department of Orthopedic Surgery, Dirksland (Netherlands); Hulst, Victor P.M. van der [Onze Lieve Vrouwe Gasthuis, Department of Radiology, Postbox 95500, Amsterdam (Netherlands); Willems, W.J. [Delairesse Kliniek, Department of Orthopedic Surgery, Amsterdam (Netherlands)

    2014-04-15

    The purpose of this study is to investigate if magnetic resonance imaging with intra-articular contrast (MR-arthro) is as reliable as three-dimensionally reconstructed computed tomography imaging (3D-CT) in quantifying the glenoid bone loss in patients with anterior shoulder instability. Thirty-five patients were included. Sagittal MR-arthro and 3D-CT images of the glenoid surface were obtained pre-operatively. Two observers measured these images twice with OsiriX software in a randomized and blinded way. The intraclass correlations (ICC) of the intra- and inter-observer reliability within one method and an additional Bland-Altman plot for calculating agreement between the two methods were obtained. The joint estimates of the intra-observer reliability, taking into account the data from both observer A and B, for 3D-CT and MR-arthro were good to excellent. The intra-observer reliability was 0.938 (95 % CI: 0.879, 0.968) for 3D-CT and 0.799 (95 % CI: 0.639, 0.837) for MR-arthro. The inter-observer reliability between the two observers within one method (3D-CT or MR-arthro) was moderate to good. 3D-CT: 0.724 (95 % CI: 0.236, 0.886) and MR-arthro: 0.534 (95 % CI: 0.128, 0.762). Comparing both the 3D-CT and MR-arthro method, a Bland-Altman plot showed satisfying differences with the majority of outcomes (89 %) within 1 SD. Good to excellent intra- and moderate to good inter-observer correlations and a satisfying Bland-Altman plot when compared to 3D-CT show tendencies that MR-arthro is reliable and valid for measuring bony defects of the glenoid. (orig.)

  10. High-Resolution Imaged-Based 3D Reconstruction Combined with X-Ray CT Data Enables Comprehensive Non-Destructive Documentation and Targeted Research of Astromaterials

    Science.gov (United States)

    Blumenfeld, E. H.; Evans, C. A.; Oshel, E. R.; Liddle, D. A.; Beaulieu, K.; Zeigler, R. A.; Righter, K.; Hanna, R. D.; Ketcham, R. A.

    2014-01-01

    Providing web-based data of complex and sensitive astromaterials (including meteorites and lunar samples) in novel formats enhances existing preliminary examination data on these samples and supports targeted sample requests and analyses. We have developed and tested a rigorous protocol for collecting highly detailed imagery of meteorites and complex lunar samples in non-contaminating environments. These data are reduced to create interactive 3D models of the samples. We intend to provide these data as they are acquired on NASA's Astromaterials Acquisition and Curation website at http://curator.jsc.nasa.gov/.

  11. 3D documentation and visualization of external injury findings by integration of simple photography in CT/MRI data sets (IprojeCT).

    Science.gov (United States)

    Campana, Lorenzo; Breitbeck, Robert; Bauer-Kreuz, Regula; Buck, Ursula

    2016-05-01

    This study evaluated the feasibility of documenting patterned injury using three dimensions and true colour photography without complex 3D surface documentation methods. This method is based on a generated 3D surface model using radiologic slice images (CT) while the colour information is derived from photographs taken with commercially available cameras. The external patterned injuries were documented in 16 cases using digital photography as well as highly precise photogrammetry-supported 3D structured light scanning. The internal findings of these deceased were recorded using CT and MRI. For registration of the internal with the external data, two different types of radiographic markers were used and compared. The 3D surface model generated from CT slice images was linked with the photographs, and thereby digital true-colour 3D models of the patterned injuries could be created (Image projection onto CT/IprojeCT). In addition, these external models were merged with the models of the somatic interior. We demonstrated that 3D documentation and visualization of external injury findings by integration of digital photography in CT/MRI data sets is suitable for the 3D documentation of individual patterned injuries to a body. Nevertheless, this documentation method is not a substitution for photogrammetry and surface scanning, especially when the entire bodily surface is to be recorded in three dimensions including all external findings, and when precise data is required for comparing highly detailed injury features with the injury-inflicting tool.

  12. Photogrammetric 3D reconstruction using mobile imaging

    Science.gov (United States)

    Fritsch, Dieter; Syll, Miguel

    2015-03-01

    In our paper we demonstrate the development of an Android Application (AndroidSfM) for photogrammetric 3D reconstruction that works on smartphones and tablets likewise. The photos are taken with mobile devices, and can thereafter directly be calibrated using standard calibration algorithms of photogrammetry and computer vision, on that device. Due to still limited computing resources on mobile devices, a client-server handshake using Dropbox transfers the photos to the sever to run AndroidSfM for the pose estimation of all photos by Structure-from-Motion and, thereafter, uses the oriented bunch of photos for dense point cloud estimation by dense image matching algorithms. The result is transferred back to the mobile device for visualization and ad-hoc on-screen measurements.

  13. 3D-guided CT reconstruction using time-of-flight camera

    Science.gov (United States)

    Ismail, Mahmoud; Taguchi, Katsuyuki; Xu, Jingyan; Tsui, Benjamin M. W.; Boctor, Emad M.

    2011-03-01

    We propose the use of a time-of-flight (TOF) camera to obtain the patient's body contour in 3D guided imaging reconstruction scheme in CT and C-arm imaging systems with truncated projection. In addition to pixel intensity, a TOF camera provides the 3D coordinates of each point in the captured scene with respect to the camera coordinates. Information from the TOF camera was used to obtain a digitized surface of the patient's body. The digitization points are transformed to X-Ray detector coordinates by registering the two coordinate systems. A set of points corresponding to the slice of interest are segmented to form a 2D contour of the body surface. Radon transform is applied to the contour to generate the 'trust region' for the projection data. The generated 'trust region' is integrated as an input to augment the projection data. It is used to estimate the truncated, unmeasured projections using linear interpolation. Finally the image is reconstructed using the combination of the estimated and the measured projection data. The proposed method is evaluated using a physical phantom. Projection data for the phantom were obtained using a C-arm system. Significant improvement in the reconstructed image quality near the truncation edges was observed using the proposed method as compared to that without truncation correction. This work shows that the proposed 3D guided CT image reconstruction using a TOF camera represents a feasible solution to the projection data truncation problem.

  14. Computer-assisted design of individualized femoral prosthesis according to 3D reconstruction of CT images%基于CT三维重建个体化股骨假体的计算机辅助设计

    Institute of Scientific and Technical Information of China (English)

    朱建炜; 刘璠; 董启榕; 许炜玮; 白恩忠; 黄希

    2010-01-01

    BACKGROUND: Due to individual characteristics of human body, it is difficult to well match between standard prosthesis and patient skeleton. Computer-assisted design and manufacture of individualized prosthesis can effectively prolong artificial joint lifespan and quality and reduce revision rate. However, related studies are few in China.OBJECTIVE: To explore computer-assisted design for individualized femoral head prosthesis according to three-dimensional (3D)reconstruction of CT images for improving prosthesis and affected skeleton matching.METHODS: The CT scanning image of one healthy male volunteer, with no hip joint disease, was used. His femur was scanned with GE Speed Light CT with 3.0 mm thick cross-section slices. CT 2D images were transmitted to a computer. The medical image format was translated from DICOM into bmp. Inner and external bone contours were drawn automatically or by hand and processed digitally, and then these data were downloaded into 3D Mimics8.1, and Rapidform2004 software. The 3D femoral canal model was rendered. Femur canal contours curve was downloaded into the Solidworks2004 software in the form of dxf. Femoral prosthesis was designed on the base of femoral canal contours curve.RESULTS AND CONCLUSION: The CT image was transmitted in the form of vector by a set of self-made medical image processing software. The accurate 3D femoral internal/external outline model was obtained by CT 2D image and reverse technique. Suitable femoral prosthesis was designed by means of image reverse engineering and norientation CAD. Reverse engineering and CAD provide an effective way to develop individualized prosthesis, improve the matching of prosthesis and affected skeleton, prevent prosthesis loosening and improve long-term stability.%背景:由于人体的绝对个性化特点,标准人工假体与患者骨骼之间的误差使二者难以很好匹配.计算机辅助设计和制造个体化假体克服了其他假体的缺点,可有效地延

  15. Automatic Calibration Method of Voxel Size for Cone-beam 3D-CT Scanning System

    CERN Document Server

    Yang, Min; Liu, Yipeng; Men, Fanyong; Li, Xingdong; Liu, Wenli; Wei, Dongbo

    2013-01-01

    For cone-beam three-dimensional computed tomography (3D-CT) scanning system, voxel size is an important indicator to guarantee the accuracy of data analysis and feature measurement based on 3D-CT images. Meanwhile, the voxel size changes with the movement of the rotary table along X-ray direction. In order to realize the automatic calibration of the voxel size, a new easily-implemented method is proposed. According to this method, several projections of a spherical phantom are captured at different imaging positions and the corresponding voxel size values are calculated by non-linear least square fitting. Through these interpolation values, a linear equation is obtained, which reflects the relationship between the rotary table displacement distance from its nominal zero position and the voxel size. Finally, the linear equation is imported into the calibration module of the 3D-CT scanning system, and when the rotary table is moving along X-ray direction, the accurate value of the voxel size is dynamically expo...

  16. 3D object-oriented image analysis in 3D geophysical modelling

    DEFF Research Database (Denmark)

    Fadel, I.; van der Meijde, M.; Kerle, N.

    2015-01-01

    Non-uniqueness of satellite gravity interpretation has traditionally been reduced by using a priori information from seismic tomography models. This reduction in the non-uniqueness has been based on velocity-density conversion formulas or user interpretation of the 3D subsurface structures (objects......) based on the seismic tomography models and then forward modelling these objects. However, this form of object-based approach has been done without a standardized methodology on how to extract the subsurface structures from the 3D models. In this research, a 3D object-oriented image analysis (3D OOA......) approach was implemented to extract the 3D subsurface structures from geophysical data. The approach was applied on a 3D shear wave seismic tomography model of the central part of the East African Rift System. Subsequently, the extracted 3D objects from the tomography model were reconstructed in the 3D...

  17. Needle placement for piriformis injection using 3-D imaging.

    Science.gov (United States)

    Clendenen, Steven R; Candler, Shawn A; Osborne, Michael D; Palmer, Scott C; Duench, Stephanie; Glynn, Laura; Ghazi, Salim M

    2013-01-01

    Piriformis syndrome is a pain syndrome originating in the buttock and is attributed to 6% - 8% of patients referred for the treatment of back and leg pain. The treatment for piriformis syndrome using fluoroscopy, computed tomography (CT), electromyography (EMG), and ultrasound (US) has become standard practice. The treatment of Piriformis Syndrome has evolved to include fluoroscopy and EMG with CT guidance. We present a case study of 5 successful piriformis injections using 3-D computer-assisted electromagnet needle tracking coupled with ultrasound. A 6-degree of freedom electromagnetic position tracker was attached to the ultrasound probe that allowed the system to detect the position and orientation of the probe in the magnetic field. The tracked ultrasound probe was used to find the posterior superior iliac spine. Subsequently, 3 points were captured to register the ultrasound image with the CT or magnetic resonance image scan. Moreover, after the registration was obtained, the navigation system visualized the tracked needle relative to the CT scan in real-time using 2 orthogonal multi-planar reconstructions centered at the tracked needle tip. Conversely, a recent study revealed that fluoroscopically guided injections had 30% accuracy compared to ultrasound guided injections, which tripled the accuracy percentage. This novel technique exhibited an accurate needle guidance injection precision of 98% while advancing to the piriformis muscle and avoiding the sciatic nerve. The mean (± SD) procedure time was 19.08 (± 4.9) minutes. This technique allows for electromagnetic instrument tip tracking with real-time 3-D guidance to the selected target. As with any new technique, a learning curve is expected; however, this technique could offer an alternative, minimizing radiation exposure.

  18. 基于MC算法的高质量脊柱CT图像三维重建%HIGH-QUALITY 3D RECONSTRUCTION OF SPINE CT IMAGES BASED ON MC ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    许婉露; 李彬; 田联房

    2013-01-01

    Reconstructing 3D model of spine from its CT images for providing intuitive preoperative lesion information can effectively assist the high-difficulty spine deformity corrective surgery.As traditional marching cubes (MC) algorithm has the limitations in roughness on reconstruction surface and topological ambiguity,as well as too many fragments in human spine reconstruction,in this paper we propose an improved MC algorithm which is based on edge-preserving local Gaussian filtering and 3D region growing.The algorithm adopts the edge-preserving filtering to eliminate the noises and enhance the edges,and uses the local Gaussian filtering to smooth the pending reconstruction areas for changing original cube types and reducing the number of ambiguous voxels,these effectively solve the problems of roughness on reconstruction surface and topological ambiguity.The dual-threshold segmentation algorithm based on 3D region growing is applied,which can significantly reduce the number of bone fragments reconstruction.Experimental results demonstrate that the 3D spine model reconstructed on this high-quality reconstruction algorithm can serve well the purpose of medical 3D visualisation.%从脊柱CT图像中重建出脊柱的三维模型以提供直观的术前病灶信息,能够有效辅助高难度的脊柱畸形矫正手术.针对传统MC(Marching Cubes)算法存在的重建表面不平滑、结构拓扑歧义的局限以及人体脊柱重构碎片过多的特点,提出一种基于保边局部高斯滤波与三维区域增长的改进型MC算法.该算法采用保边滤波去噪并增强边缘,局部高斯滤波平滑待重建区域以改变原有体素类型,减少二义性体素对数,有效地解决了重建表面不平滑与结构拓扑歧义问题;采用基于三维区域增长的双阈值分割算法,大大减少碎骨重建的数量.实验证明,采用高质量重建算法重建的脊柱三维模型能够满足医学三维可视化的要求.

  19. Bronchial morphometry in smokers: comparison with healthy subjects by using 3D CT

    Energy Technology Data Exchange (ETDEWEB)

    Montaudon, Michel [Unite d' Imagerie Thoracique, CHU de Bordeaux, Pessac (France); Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); INSERM, Bordeaux (France); Hopital Cardiologique, Unite d' Imagerie Thoracique, Pessac (France); Berger, Patrick; Marthan, Roger [Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); INSERM, Bordeaux (France); Service d' Exploration Fonctionnelle Respiratoire, CHU de Bordeaux, Pessac (France); Lederlin, Mathieu [Unite d' Imagerie Thoracique, CHU de Bordeaux, Pessac (France); Tunon-de-Lara, Jose Manuel [Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); INSERM, Bordeaux (France); Service des Maladies Respiratoires, CHU de Bordeaux, Pessac (France); Laurent, Francois [Unite d' Imagerie Thoracique, CHU de Bordeaux, Pessac (France); Universite Bordeaux 2, Laboratoire de Physiologie Cellulaire Respiratoire, Bordeaux (France); INSERM, Bordeaux (France)

    2009-06-15

    The assessment of airway dimensions in patients with airway disease by using computed tomography (CT) has been limited by the obliquity of bronchi, the ability to identify the bronchial generation, and the limited number of bronchial measurements. The aims of the present study were (i) to analyze cross-sectional bronchial dimensions after automatic orthogonal reconstruction of all visible bronchi on CT images, and (ii) to compare bronchial morphometry between smokers and nonsmokers. CT and pulmonary function tests were performed in 18 males separated into two groups: 9 nonsmokers and 9 smokers. Bronchial wall area (WA) and lumen area (LA) were assessed using dedicated 3D software able to provide accurate cross-sectional measurements of all visible bronchi on CT. WA/LA and WA/(WA+LA) ratios were computed and all parameters were compared between both groups. Smokers demonstrated greater WA, smaller LA, and consequently greater LA/WA and LA/(WA+LA) ratios than nonsmokers. These differences occurred downward starting at the fourth bronchial generation. 3D quantitative CT method is able to demonstrate significant changes in bronchial morphometry related to tobacco consumption. (orig.)

  20. Handbook of 3D machine vision optical metrology and imaging

    CERN Document Server

    Zhang, Song

    2013-01-01

    With the ongoing release of 3D movies and the emergence of 3D TVs, 3D imaging technologies have penetrated our daily lives. Yet choosing from the numerous 3D vision methods available can be frustrating for scientists and engineers, especially without a comprehensive resource to consult. Filling this gap, Handbook of 3D Machine Vision: Optical Metrology and Imaging gives an extensive, in-depth look at the most popular 3D imaging techniques. It focuses on noninvasive, noncontact optical methods (optical metrology and imaging). The handbook begins with the well-studied method of stereo vision and

  1. Progress in 3D imaging and display by integral imaging

    Science.gov (United States)

    Martinez-Cuenca, R.; Saavedra, G.; Martinez-Corral, M.; Pons, A.; Javidi, B.

    2009-05-01

    Three-dimensionality is currently considered an important added value in imaging devices, and therefore the search for an optimum 3D imaging and display technique is a hot topic that is attracting important research efforts. As main value, 3D monitors should provide the observers with different perspectives of a 3D scene by simply varying the head position. Three-dimensional imaging techniques have the potential to establish a future mass-market in the fields of entertainment and communications. Integral imaging (InI), which can capture true 3D color images, has been seen as the right technology to 3D viewing to audiences of more than one person. Due to the advanced degree of development, InI technology could be ready for commercialization in the coming years. This development is the result of a strong research effort performed along the past few years by many groups. Since Integral Imaging is still an emerging technology, the first aim of the "3D Imaging and Display Laboratory" at the University of Valencia, has been the realization of a thorough study of the principles that govern its operation. Is remarkable that some of these principles have been recognized and characterized by our group. Other contributions of our research have been addressed to overcome some of the classical limitations of InI systems, like the limited depth of field (in pickup and in display), the poor axial and lateral resolution, the pseudoscopic-to-orthoscopic conversion, the production of 3D images with continuous relief, or the limited range of viewing angles of InI monitors.

  2. Description of patellar movement by 3D parameters obtained from dynamic CT acquisition

    Science.gov (United States)

    de Sá Rebelo, Marina; Moreno, Ramon Alfredo; Gobbi, Riccardo Gomes; Camanho, Gilberto Luis; de Ávila, Luiz Francisco Rodrigues; Demange, Marco Kawamura; Pecora, Jose Ricardo; Gutierrez, Marco Antonio

    2014-03-01

    The patellofemoral joint is critical in the biomechanics of the knee. The patellofemoral instability is one condition that generates pain, functional impairment and often requires surgery as part of orthopedic treatment. The analysis of the patellofemoral dynamics has been performed by several medical image modalities. The clinical parameters assessed are mainly based on 2D measurements, such as the patellar tilt angle and the lateral shift among others. Besides, the acquisition protocols are mostly performed with the leg laid static at fixed angles. The use of helical multi slice CT scanner can allow the capture and display of the joint's movement performed actively by the patient. However, the orthopedic applications of this scanner have not yet been standardized or widespread. In this work we present a method to evaluate the biomechanics of the patellofemoral joint during active contraction using multi slice CT images. This approach can greatly improve the analysis of patellar instability by displaying the physiology during muscle contraction. The movement was evaluated by computing its 3D displacements and rotations from different knee angles. The first processing step registered the images in both angles based on the femuŕs position. The transformation matrix of the patella from the images was then calculated, which provided the rotations and translations performed by the patella from its position in the first image to its position in the second image. Analysis of these parameters for all frames provided real 3D information about the patellar displacement.

  3. Role of 3D-CT for orthodontic and ENT evaluation in Goldenhar syndrome.

    Science.gov (United States)

    Saccomanno, S; Greco, F; D'Alatri, L; De Corso, E; Pandolfini, M; Sergi, B; Pirronti, T; Deli, R

    2014-08-01

    Goldenhar syndrome is a congenital condition that includes anomalies of the derivatives of the first and second brachial arches, vertebral defects and ocular abnormalities. It is also known as oculo-auriculo-vertebrale syndrome (OAVS), hemifacial microsomia, or first or second brachial arch syndrome. It was first described by Van Duyse in 1882 and better studied by M. Goldenhar in 1952. Its treatment requires a multidisciplinary approach. Herein, we describe the value of 3D-CT evaluation in a patient with Goldenhar syndrome, with particular regard to planning diagnostic and therapeutic approach. A 7-year-old boy with Goldenhar syndrome with definite post-natal genetic diagnosis was referred to our Department of Radiology for neuroimaging of the temporal bone. By 3D-CT evaluation of this young patient we observed the asymmetry of the condyles with the right one dysmorphic, short and wide; the auricle of the right ear was replaced by a dysmorphic rough; the right middle ear had a hypoplastic tympanic cavity and the internal auditory canal of right ear was atresic. In our experience, 3D-CT is a powerful diagnostic instrument and offers many advantages: volumetric reproduction of cranium and soft tissues, no overlap of anatomic parts that limits the visibility of various structures, high precision and assurance of images, and a constant and easily reproducible reference system. In our case, 3D-CT offered a very complete evaluation of all malformations of mandibular and temporal bone that characterize this syndrome and representing an important step for ENT and orthodontic therapeutic approaches.

  4. Acute Bochdalek hernia in an adult:A case report of a 3D image

    Institute of Scientific and Technical Information of China (English)

    Rejeb Imen; Chakroun-Walha Olfa; Ksibi Hichem; Nasri Abdennour; Chtara Kamilia; Chaari Adel; Rekik Noureddine

    2016-01-01

    A 61-year-old male was found to have a bilateral Bochdalek hernia on routine CT during admission for acute respiratory failure. The chest X-ray showed a left paracardiac mass having a diameter of 6 cm. This mass was initially considered as a mediastinal tumor. However, CT scan showed a bilateral large defect of the posteromedial portion of the diaphragm and mesenteric fat. 3D imaging was also useful for the stereographic perception of Bochdalek hernia. Although Bochdalek hernia is not rare, to our knowl-edge, this is the first case of Bochdalek hernia continued transverse colon observed by spiral CT 3D imaging.

  5. Single minimum incision endoscopic radical nephrectomy for renal tumors with preoperative virtual navigation using 3D-CT volume-rendering

    Directory of Open Access Journals (Sweden)

    Shioyama Yasukazu

    2010-04-01

    Full Text Available Abstract Background Single minimum incision endoscopic surgery (MIES involves the use of a flexible high-definition laparoscope to facilitate open surgery. We reviewed our method of radical nephrectomy for renal tumors, which is single MIES combined with preoperative virtual surgery employing three-dimensional CT images reconstructed by the volume rendering method (3D-CT images in order to safely and appropriately approach the renal hilar vessels. We also assessed the usefulness of 3D-CT images. Methods Radical nephrectomy was done by single MIES via the translumbar approach in 80 consecutive patients. We performed the initial 20 MIES nephrectomies without preoperative 3D-CT images and the subsequent 60 MIES nephrectomies with preoperative 3D-CT images for evaluation of the renal hilar vessels and the relation of each tumor to the surrounding structures. On the basis of the 3D information, preoperative virtual surgery was performed with a computer. Results Single MIES nephrectomy was successful in all patients. In the 60 patients who underwent 3D-CT, the number of renal arteries and veins corresponded exactly with the preoperative 3D-CT data (100% sensitivity and 100% specificity. These 60 nephrectomies were completed with a shorter operating time and smaller blood loss than the initial 20 nephrectomies. Conclusions Single MIES radical nephrectomy combined with 3D-CT and virtual surgery achieved a shorter operating time and less blood loss, possibly due to safer and easier handling of the renal hilar vessels.

  6. Super deep 3D images from a 3D omnifocus video camera.

    Science.gov (United States)

    Iizuka, Keigo

    2012-02-20

    When using stereographic image pairs to create three-dimensional (3D) images, a deep depth of field in the original scene enhances the depth perception in the 3D image. The omnifocus video camera has no depth of field limitations and produces images that are in focus throughout. By installing an attachment on the omnifocus video camera, real-time super deep stereoscopic pairs of video images were obtained. The deeper depth of field creates a larger perspective image shift, which makes greater demands on the binocular fusion of human vision. A means of reducing the perspective shift without harming the depth of field was found.

  7. Creative 3D-image fusion across 3-module [PET+CT+MR] based on characteristic registration in unification%基于特征配准的[PET+CT+MR]“三机三维”影像一体化融合尝试

    Institute of Scientific and Technical Information of China (English)

    彭鳒侨; 鞠向阳; 李新春; 韩佩; 朱巧洪; 白波

    2012-01-01

    目的 尝试以基于图像特征的二维图像配准方法,实现PET、MR和CT异机图像之间的精确三维融合.方法 输入PET/CT/MR原始数据后,采用数字化格式转换,设计“9点3面”立体定位法进行配准,在Mimics实时工作站按照信息交互自动融合模式并通过信号叠加技术施行图像融合.结果 以头、胸、腹为实例交叉试验[CT+ MR]、[PET+MR]、[PET+CT]和[PET+ CT+ MR]立体图像的异机融合,生成了同时分辨软硬组织病灶性质和位置的互补影像.结论 在现阶段,此种异机融合方法是对同机成像功用的必要补充.%Objective To attempt a registration approach of 2-dimension (2D) image based on image characteristic, in order to accomplish accurate fusion of 3-dimension (3D) from PET, CT and MR images one by one. Methods Digital format was converted after original data of PET/CT/MR input, cubic oriented scheme of "9-point and 3-plane" for co-registration was designed, and image fusion was implemented at real-time workstation Mimics based on auto-fusing style of information exchanged by signal overlaid technique. Results Cross-modality fusion from cubic images of [CT+MR], [PET+MR], [PET+CT] and [PET+CT+MR] of patients' cranium, chest and abdominal were mutually practiced, complementary images of distinguishing nature and location of lesions between soft and hard tissue were simultaneously created. Conclusion Currently, this sort of multiple modality fusion is an essential complement for the existing function of single modality imaging.

  8. 3D Image Synthesis for B—Reps Objects

    Institute of Scientific and Technical Information of China (English)

    黄正东; 彭群生; 等

    1991-01-01

    This paper presents a new algorithm for generating 3D images of B-reps objects with trimmed surface boundaries.The 3D image is a discrete voxel-map representation within a Cubic Frame Buffer (CFB).The definition of 3D images for curve,surface and solid object are introduced which imply the connectivity and fidelity requirements.Adaptive Forward Differencing matrix (AFD-matrix) for 1D-3D manifolds in 3D space is developed.By setting rules to update the AFD-matrix,the forward difference direction and stepwise can be adjusted.Finally,an efficient algorithm is presented based on the AFD-matrix concept for converting the object in 3D space to 3D image in 3D discrete space.

  9. IMAGE SELECTION FOR 3D MEASUREMENT BASED ON NETWORK DESIGN

    Directory of Open Access Journals (Sweden)

    T. Fuse

    2015-05-01

    Full Text Available 3D models have been widely used by spread of many available free-software. On the other hand, enormous images can be easily acquired, and images are utilized for creating the 3D models recently. However, the creation of 3D models by using huge amount of images takes a lot of time and effort, and then efficiency for 3D measurement are required. In the efficiency strategy, the accuracy of the measurement is also required. This paper develops an image selection method based on network design that means surveying network construction. The proposed method uses image connectivity graph. By this, the image selection problem is regarded as combinatorial optimization problem and the graph cuts technique can be applied. Additionally, in the process of 3D reconstruction, low quality images and similarity images are extracted and removed. Through the experiments, the significance of the proposed method is confirmed. Potential to efficient and accurate 3D measurement is implied.

  10. Assessing 3D tunnel position in ACL reconstruction using a novel single image 3D-2D registration

    Science.gov (United States)

    Kang, X.; Yau, W. P.; Otake, Y.; Cheung, P. Y. S.; Hu, Y.; Taylor, R. H.

    2012-02-01

    The routinely used procedure for evaluating tunnel positions following anterior cruciate ligament (ACL) reconstructions based on standard X-ray images is known to pose difficulties in terms of obtaining accurate measures, especially in providing three-dimensional tunnel positions. This is largely due to the variability in individual knee joint pose relative to X-ray plates. Accurate results were reported using postoperative CT. However, its extensive usage in clinical routine is hampered by its major requirement of having CT scans of individual patients, which is not available for most ACL reconstructions. These difficulties are addressed through the proposed method, which aligns a knee model to X-ray images using our novel single-image 3D-2D registration method and then estimates the 3D tunnel position. In the proposed method, the alignment is achieved by using a novel contour-based 3D-2D registration method wherein image contours are treated as a set of oriented points. However, instead of using some form of orientation weighting function and multiplying it with a distance function, we formulate the 3D-2D registration as a probability density estimation using a mixture of von Mises-Fisher-Gaussian (vMFG) distributions and solve it through an expectation maximization (EM) algorithm. Compared with the ground-truth established from postoperative CT, our registration method in an experiment using a plastic phantom showed accurate results with errors of (-0.43°+/-1.19°, 0.45°+/-2.17°, 0.23°+/-1.05°) and (0.03+/-0.55, -0.03+/-0.54, -2.73+/-1.64) mm. As for the entry point of the ACL tunnel, one of the key measurements, it was obtained with high accuracy of 0.53+/-0.30 mm distance errors.

  11. The clinical value of PET-CT 3D mode brain image on the localizing the epileptic foci%PET-CT脑3D显像在癫痫定位的临床应用价值

    Institute of Scientific and Technical Information of China (English)

    陈伟华

    2009-01-01

    Objective To assess the value of 18F-FDG PET cerebral 3D mode on the localizing the epileptic foci.Methods 13 patients with epilepsy,The brain scans with 3D mode were performed in all the patients.The images were analyzed by eyes and semi-quantitative method by two experienced nuclear medicine physicians.The scalp electroencephalogram(EEG)was performed in all the patients.Among them,Electrocorticogram (EcoG) or depth electroencephalogram were performed in 2 cases to verify the results of PET. MRI and/or CT were obtained in 12 cases.Results In 13 patients,92.3% was abnormal displaying hypometabolic foci on PET imaging(12/13cases).PET was more sensitive than EEG and MRI/CT to detect the lesions (92.3%、69.2% and 33.3%℅ respectively,χ2 were 14.3 and 35.0,all P<0.01).PET detected solitary lesion in 61.5% of patients, more higher than EEG(61.5% vs 38.4%,χ2 was 23.1, P<0.01). Comparing with golden standard of EcoG or depth electroencephalogram,the sensitivity and specificity of PET to localize the epileptic foci were 95% and 89%.Conclusion 18F-FDG PET is a sensitive and accurate image modality on the localizing the epileptic foci. It is useful to direct surgical treatment and orientating radiation therapy.%目的 研究18F-FDG PET-CT脑3D显像对致痫灶定位的应用价值.方法 癫痫患者13例,皆行18F-FDG脑三维PET显像,通过目测和半定量方法分析图像.所有患者均行EEG检查,其中2例行皮层脑电图(EcoG)或深部脑电图(DEEG);12例行脑MRI或CT检查.结果 (1)13例中,PET阳性表现为低代谢灶者检出率为92.3%(12/13例),明显高于EEG和脑MRI/CT(分别为92.3%、69.2%、33.3%,χ2分别为14.3、35.0,P均<0.01).单病灶检出率PET明显高于EEG(分别为61.5%和38.4%,χ2=23.1,P<0.01).与皮层脑电图(EcoG)或深部脑电图(DEEG)相比较,PET对致痫灶的检出灵敏度为95%,定位准确性为89%.结论 18F-FDG PET在致痫灶的检出及定位方面有较高的灵敏度和准确性;在引导癫痫外科手术

  12. Automatic 2D-to-3D image conversion using 3D examples from the internet

    Science.gov (United States)

    Konrad, J.; Brown, G.; Wang, M.; Ishwar, P.; Wu, C.; Mukherjee, D.

    2012-03-01

    The availability of 3D hardware has so far outpaced the production of 3D content. Although to date many methods have been proposed to convert 2D images to 3D stereopairs, the most successful ones involve human operators and, therefore, are time-consuming and costly, while the fully-automatic ones have not yet achieved the same level of quality. This subpar performance is due to the fact that automatic methods usually rely on assumptions about the captured 3D scene that are often violated in practice. In this paper, we explore a radically different approach inspired by our work on saliency detection in images. Instead of relying on a deterministic scene model for the input 2D image, we propose to "learn" the model from a large dictionary of stereopairs, such as YouTube 3D. Our new approach is built upon a key observation and an assumption. The key observation is that among millions of stereopairs available on-line, there likely exist many stereopairs whose 3D content matches that of the 2D input (query). We assume that two stereopairs whose left images are photometrically similar are likely to have similar disparity fields. Our approach first finds a number of on-line stereopairs whose left image is a close photometric match to the 2D query and then extracts depth information from these stereopairs. Since disparities for the selected stereopairs differ due to differences in underlying image content, level of noise, distortions, etc., we combine them by using the median. We apply the resulting median disparity field to the 2D query to obtain the corresponding right image, while handling occlusions and newly-exposed areas in the usual way. We have applied our method in two scenarios. First, we used YouTube 3D videos in search of the most similar frames. Then, we repeated the experiments on a small, but carefully-selected, dictionary of stereopairs closely matching the query. This, to a degree, emulates the results one would expect from the use of an extremely large 3D

  13. Deformable 3D-2D registration for CT and its application to low dose tomographic fluoroscopy

    Science.gov (United States)

    Flach, Barbara; Brehm, Marcus; Sawall, Stefan; Kachelrieß, Marc

    2014-12-01

    Many applications in medical imaging include image registration for matching of images from the same or different modalities. In the case of full data sampling, the respective reconstructed images are usually of such a good image quality that standard deformable volume-to-volume (3D-3D) registration approaches can be applied. But research in temporal-correlated image reconstruction and dose reductions increases the number of cases where rawdata are available from only few projection angles. Here, deteriorated image quality leads to non-acceptable deformable volume-to-volume registration results. Therefore a registration approach is required that is robust against a decreasing number of projections defining the target position. We propose a deformable volume-to-rawdata (3D-2D) registration method that aims at finding a displacement vector field maximizing the alignment of a CT volume and the acquired rawdata based on the sum of squared differences in rawdata domain. The registration is constrained by a regularization term in accordance with a fluid-based diffusion. Both cost function components, the rawdata fidelity and the regularization term, are optimized in an alternating manner. The matching criterion is optimized by a conjugate gradient descent for nonlinear functions, while the regularization is realized by convolution of the vector fields with Gaussian kernels. We validate the proposed method and compare it to the demons algorithm, a well-known 3D-3D registration method. The comparison is done for a range of 4-60 target projections using datasets from low dose tomographic fluoroscopy as an application example. The results show a high correlation to the ground truth target position without introducing artifacts even in the case of very few projections. In particular the matching in the rawdata domain is improved compared to the 3D-3D registration for the investigated range. The proposed volume-to-rawdata registration increases the robustness regarding sparse

  14. Value of 3-D CT in classifying acetabular fractures during orthopedic residency training.

    Science.gov (United States)

    Garrett, Jeffrey; Halvorson, Jason; Carroll, Eben; Webb, Lawrence X

    2012-05-01

    The complex anatomy of the pelvis and acetabulum have historically made classification and interpretation of acetabular fractures difficult for orthopedic trainees. The addition of 3-dimensional (3-D) computed tomography (CT) scan has gained popularity in preoperative planning, identification, and education of acetabular fractures given their complexity. Therefore, the authors examined the value of 3-D CT compared with conventional radiography in classifying acetabular fractures at different levels of orthopedic training. Their hypothesis was that 3-D CT would improve correct identification of acetabular fractures compared with conventional radiography.The classic Letournel fracture pattern classification system was presented in quiz format to 57 orthopedic residents and 20 fellowship-trained orthopedic traumatologists. A case consisted of (1) plain radiographs and 2-dimensional axial CT scans or (2) 3-D CT scans. All levels of training showed significant improvement in classifying acetabular fractures with 3-D vs 2-D CT, with the greatest benefit from 3-D CT found in junior residents (postgraduate years 1-3).Three-dimensional CT scans can be an effective educational tool for understanding the complex spatial anatomy of the pelvis, learning acetabular fracture patterns, and correctly applying a widely accepted fracture classification system.

  15. CT virtual endoscopy and 3D stereoscopic visualisation in the evaluation of coronary stenting.

    Science.gov (United States)

    Sun, Z; Lawrence-Brown

    2009-10-01

    The aim of this case report is to present the additional value provided by CT virtual endoscopy and 3D stereoscopic visualisation when compared with 2D visualisations in the assessment of coronary stenting. A 64-year old patient was treated with left coronary stenting 8 years ago and recently followed up with multidetector row CT angiography. An in-stent restenosis of the left coronary artery was suspected based on 2D axial and multiplanar reformatted images. 3D virtual endoscopy was generated to demonstrate the smooth intraluminal surface of coronary artery wall, and there was no evidence of restenosis or intraluminal irregularity. Virtual fly-through of the coronary artery was produced to examine the entire length of the coronary artery with the aim of demonstrating the intraluminal changes following placement of the coronary stent. In addition, stereoscopic views were generated to show the relationship between coronary artery branches and the coronary stent. In comparison with traditional 2D visualisations, virtual endoscopy was useful for assessment of the intraluminal appearance of the coronary artery wall following coronary stent implantation, while stereoscopic visualisation improved observers' understanding of the complex cardiac structures. Thus, both methods could be used as a complementary tool in cardiac imaging.

  16. Augmented Reality Imaging System: 3D Viewing of a Breast Cancer

    Science.gov (United States)

    Douglas, David B.; Boone, John M.; Petricoin, Emanuel; Liotta, Lance; Wilson, Eugene

    2016-01-01

    Objective To display images of breast cancer from a dedicated breast CT using Depth 3-Dimensional (D3D) augmented reality. Methods A case of breast cancer imaged using contrast-enhanced breast CT (Computed Tomography) was viewed with the augmented reality imaging, which uses a head display unit (HDU) and joystick control interface. Results The augmented reality system demonstrated 3D viewing of the breast mass with head position tracking, stereoscopic depth perception, focal point convergence and the use of a 3D cursor and joy-stick enabled fly through with visualization of the spiculations extending from the breast cancer. Conclusion The augmented reality system provided 3D visualization of the breast cancer with depth perception and visualization of the mass's spiculations. The augmented reality system should be further researched to determine the utility in clinical practice. PMID:27774517

  17. Dynamic contrast-enhanced 3D photoacoustic imaging

    Science.gov (United States)

    Wong, Philip; Kosik, Ivan; Carson, Jeffrey J. L.

    2013-03-01

    Photoacoustic imaging (PAI) is a hybrid imaging modality that integrates the strengths from both optical imaging and acoustic imaging while simultaneously overcoming many of their respective weaknesses. In previous work, we reported on a real-time 3D PAI system comprised of a 32-element hemispherical array of transducers. Using the system, we demonstrated the ability to capture photoacoustic data, reconstruct a 3D photoacoustic image, and display select slices of the 3D image every 1.4 s, where each 3D image resulted from a single laser pulse. The present study aimed to exploit the rapid imaging speed of an upgraded 3D PAI system by evaluating its ability to perform dynamic contrast-enhanced imaging. The contrast dynamics can provide rich datasets that contain insight into perfusion, pharmacokinetics and physiology. We captured a series of 3D PA images of a flow phantom before and during injection of piglet and rabbit blood. Principal component analysis was utilized to classify the data according to its spatiotemporal information. The results suggested that this technique can be used to separate a sequence of 3D PA images into a series of images representative of main features according to spatiotemporal flow dynamics.

  18. Light field display and 3D image reconstruction

    Science.gov (United States)

    Iwane, Toru

    2016-06-01

    Light field optics and its applications become rather popular in these days. With light field optics or light field thesis, real 3D space can be described in 2D plane as 4D data, which we call as light field data. This process can be divided in two procedures. First, real3D scene is optically reduced with imaging lens. Second, this optically reduced 3D image is encoded into light field data. In later procedure we can say that 3D information is encoded onto a plane as 2D data by lens array plate. This transformation is reversible and acquired light field data can be decoded again into 3D image with the arrayed lens plate. "Refocusing" (focusing image on your favorite point after taking a picture), light-field camera's most popular function, is some kind of sectioning process from encoded 3D data (light field data) to 2D image. In this paper at first I show our actual light field camera and our 3D display using acquired and computer-simulated light field data, on which real 3D image is reconstructed. In second I explain our data processing method whose arithmetic operation is performed not in Fourier domain but in real domain. Then our 3D display system is characterized by a few features; reconstructed image is of finer resolutions than density of arrayed lenses and it is not necessary to adjust lens array plate to flat display on which light field data is displayed.

  19. Full Parallax Integral 3D Display and Image Processing Techniques

    Directory of Open Access Journals (Sweden)

    Byung-Gook Lee

    2015-02-01

    Full Text Available Purpose – Full parallax integral 3D display is one of the promising future displays that provide different perspectives according to viewing direction. In this paper, the authors review the recent integral 3D display and image processing techniques for improving the performance, such as viewing resolution, viewing angle, etc.Design/methodology/approach – Firstly, to improve the viewing resolution of 3D images in the integral imaging display with lenslet array, the authors present 3D integral imaging display with focused mode using the time-multiplexed display. Compared with the original integral imaging with focused mode, the authors use the electrical masks and the corresponding elemental image set. In this system, the authors can generate the resolution-improved 3D images with the n×n pixels from each lenslet by using n×n time-multiplexed display. Secondly, a new image processing technique related to the elemental image generation for 3D scenes is presented. With the information provided by the Kinect device, the array of elemental images for an integral imaging display is generated.Findings – From their first work, the authors improved the resolution of 3D images by using the time-multiplexing technique through the demonstration of the 24 inch integral imaging system. Authors’ method can be applied to a practical application. Next, the proposed method with the Kinect device can gain a competitive advantage over other methods for the capture of integral images of big 3D scenes. The main advantage of fusing the Kinect and the integral imaging concepts is the acquisition speed, and the small amount of handled data.Originality / Value – In this paper, the authors review their recent methods related to integral 3D display and image processing technique.Research type – general review.

  20. 3D Imaging with Structured Illumination for Advanced Security Applications

    Energy Technology Data Exchange (ETDEWEB)

    Birch, Gabriel Carisle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Dagel, Amber Lynn [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kast, Brian A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Smith, Collin S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Three-dimensional (3D) information in a physical security system is a highly useful dis- criminator. The two-dimensional data from an imaging systems fails to provide target dis- tance and three-dimensional motion vector, which can be used to reduce nuisance alarm rates and increase system effectiveness. However, 3D imaging devices designed primarily for use in physical security systems are uncommon. This report discusses an architecture favorable to physical security systems; an inexpensive snapshot 3D imaging system utilizing a simple illumination system. The method of acquiring 3D data, tests to understand illumination de- sign, and software modifications possible to maximize information gathering capability are discussed.

  1. 3D passive integral imaging using compressive sensing.

    Science.gov (United States)

    Cho, Myungjin; Mahalanobis, Abhijit; Javidi, Bahram

    2012-11-19

    Passive 3D sensing using integral imaging techniques has been well studied in the literature. It has been shown that a scene can be reconstructed at various depths using several 2D elemental images. This provides the ability to reconstruct objects in the presence of occlusions, and passively estimate their 3D profile. However, high resolution 2D elemental images are required for high quality 3D reconstruction. Compressive Sensing (CS) provides a way to dramatically reduce the amount of data that needs to be collected to form the elemental images, which in turn can reduce the storage and bandwidth requirements. In this paper, we explore the effects of CS in acquisition of the elemental images, and ultimately on passive 3D scene reconstruction and object recognition. Our experiments show that the performance of passive 3D sensing systems remains robust even when elemental images are recovered from very few compressive measurements.

  2. 3D Objects Reconstruction from Image Data

    OpenAIRE

    Cír, Filip

    2008-01-01

    Tato práce se zabývá 3D rekonstrukcí z obrazových dat. Jsou popsány možnosti a přístupy k optickému skenování. Ruční optický 3D skener se skládá z kamery a zdroje čárového laseru, který je vzhledem ke kameře upevněn pod určitým úhlem. Je navržena vhodná podložka se značkami a je popsán algoritmus pro jejich real-time detekci. Po detekci značek lze vypočítat pozici a orientaci kamery. Na závěr je popsána detekce laseru a postup při výpočtu bodů na povrchu objektu pomocí triangulace. This pa...

  3. Semi-automatic 3D segmentation of costal cartilage in CT data from Pectus Excavatum patients

    Science.gov (United States)

    Barbosa, Daniel; Queirós, Sandro; Rodrigues, Nuno; Correia-Pinto, Jorge; Vilaça, J.

    2015-03-01

    One of the current frontiers in the clinical management of Pectus Excavatum (PE) patients is the prediction of the surgical outcome prior to the intervention. This can be done through computerized simulation of the Nuss procedure, which requires an anatomically correct representation of the costal cartilage. To this end, we take advantage of the costal cartilage tubular structure to detect it through multi-scale vesselness filtering. This information is then used in an interactive 2D initialization procedure which uses anatomical maximum intensity projections of 3D vesselness feature images to efficiently initialize the 3D segmentation process. We identify the cartilage tissue centerlines in these projected 2D images using a livewire approach. We finally refine the 3D cartilage surface through region-based sparse field level-sets. We have tested the proposed algorithm in 6 noncontrast CT datasets from PE patients. A good segmentation performance was found against reference manual contouring, with an average Dice coefficient of 0.75±0.04 and an average mean surface distance of 1.69+/-0.30mm. The proposed method requires roughly 1 minute for the interactive initialization step, which can positively contribute to an extended use of this tool in clinical practice, since current manual delineation of the costal cartilage can take up to an hour.

  4. 3D augmented reality with integral imaging display

    Science.gov (United States)

    Shen, Xin; Hua, Hong; Javidi, Bahram

    2016-06-01

    In this paper, a three-dimensional (3D) integral imaging display for augmented reality is presented. By implementing the pseudoscopic-to-orthoscopic conversion method, elemental image arrays with different capturing parameters can be transferred into the identical format for 3D display. With the proposed merging algorithm, a new set of elemental images for augmented reality display is generated. The newly generated elemental images contain both the virtual objects and real world scene with desired depth information and transparency parameters. The experimental results indicate the feasibility of the proposed 3D augmented reality with integral imaging.

  5. De la manipulation des images 3D

    Directory of Open Access Journals (Sweden)

    Geneviève Pinçon

    2012-04-01

    Full Text Available Si les technologies 3D livrent un enregistrement précis et pertinent des graphismes pariétaux, elles offrent également des applications particulièrement intéressantes pour leur analyse. À travers des traitements sur nuage de points et des simulations, elles autorisent un large éventail de manipulations touchant autant à l’observation qu’à l’étude des œuvres pariétales. Elles permettent notamment une perception affinée de leur volumétrie, et deviennent des outils de comparaison de formes très utiles dans la reconstruction des chronologies pariétales et dans l’appréhension des analogies entre différents sites. Ces outils analytiques sont ici illustrés par les travaux originaux menés sur les sculptures pariétales des abris du Roc-aux-Sorciers (Angles-sur-l’Anglin, Vienne et de la Chaire-à-Calvin (Mouthiers-sur-Boëme, Charente.If 3D technologies allow an accurate and relevant recording of rock art, they also offer several interesting applications for its analysis. Through spots clouds treatments and simulations, they permit a wide range of manipulations concerning figurations observation and study. Especially, they allow a fine perception of their volumetry. They become efficient tools for forms comparisons, very useful in the reconstruction of graphic ensemble chronologies and for inter-sites analogies. These analytical tools are illustrated by the original works done on the sculptures of Roc-aux-Sorciers (Angles-sur-l’Anglin, Vienne and Chaire-à-Calvin (Mouthiers-sur-Boëme, Charente rock-shelters.

  6. Mediastinal fibrosis with pulmonary artery obstruction; diagnosis and investigation with helical CT imaging including 3-dimensional reconstructions; Pulomonalarterienstenose bei aggresiver Mediastinalfibrose; Diagnostik und 3D-Darstellung mittels helikaler CT-Untersuchung

    Energy Technology Data Exchange (ETDEWEB)

    Kolbe, M. [Inst. fuer Diagnostische Radiologie, Kantonsspital Basel (Switzerland); Helwig, A. [Inst. fuer Diagnostische Radiologie, Kantonsspital Basel (Switzerland); Habicht, J.M. [Klinik fuer Herz-Torax-Chirurgie, Universitaetskliniken Basel (Switzerland); Steinbruch, W. [Inst. fuer Diagnostische Radiologie, Kantonsspital Basel (Switzerland)

    1997-07-01

    An aggressive mediastinal fibrosis was found in a 42-year-old female, suffering from dysphagia, stabbing pain in the chest, and an unclear weight loss. In this case, the rare combination of esophageal involvement, bronchial narrowing, and pulmonary artery obstruction could easily be demonstrated with a barium study and a helical CT examination including three-dimensional reconstructions. (orig.) [Deutsch] Wir stellen den Fall einer 42jaehrigen Patientin vor, welche zur Abklaerung einer zunehmenden Dysphagie, stechender Thoraxschmerzen und eines Gewichtsverlustes hospitalisiert wurde. Mittels klinischer und radiologischer Abklaerung konnte eine aggressive Mediastinalfibrose diagnostiziert werden. Die seltene Kombination einer Oesophaguseinengung mit Pulmonalarterienstenosen sowie einer Bronchuskompression konnte nichtinvasiv mittels Oesophagogramm und helikaler CT-Untersuchung zuverlaessig und schnell dargestellt werden. (orig.)

  7. Calibration of Images with 3D range scanner data

    OpenAIRE

    Adalid López, Víctor Javier

    2009-01-01

    Projecte fet en col.laboració amb EPFL 3D laser range scanners are used in extraction of the 3D data in a scene. Main application areas are architecture, archeology and city planning. Thought the raw scanner data has a gray scale values, the 3D data can be merged with colour camera image values to get textured 3D model of the scene. Also these devices are able to take a reliable copy in 3D form objects, with a high level of accuracy. Therefore, they scanned scenes can be use...

  8. 3D Ground Penetrating Imaging Radar

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    GPiR (ground-penetrating imaging radar) is a new technology for mapping the shallow subsurface, including society’s underground infrastructure. Applications for this technology include efficient and precise mapping of buried utilities on a large scale.

  9. Optical-CT 3D Dosimetry Using Fresnel Lenses with Minimal Refractive-Index Matching Fluid.

    Directory of Open Access Journals (Sweden)

    Steven Bache

    Full Text Available Telecentric optical computed tomography (optical-CT is a state-of-the-art method for visualizing and quantifying 3-dimensional dose distributions in radiochromic dosimeters. In this work a prototype telecentric system (DFOS-Duke Fresnel Optical-CT Scanner is evaluated which incorporates two substantial design changes: the use of Fresnel lenses (reducing lens costs from $10-30K t0 $1-3K and the use of a 'solid tank' (which reduces noise, and the volume of refractively matched fluid from 1 ltr to 10 cc. The efficacy of DFOS was evaluated by direct comparison against commissioned scanners in our lab. Measured dose distributions from all systems were compared against the predicted dose distributions from a commissioned treatment planning system (TPS. Three treatment plans were investigated including a simple four-field box treatment, a multiple small field delivery, and a complex IMRT treatment. Dosimeters were imaged within 2 h post irradiation, using consistent scanning techniques (360 projections acquired at 1 degree intervals, reconstruction at 2mm. DFOS efficacy was evaluated through inspection of dose line-profiles, and 2D and 3D dose and gamma maps. DFOS/TPS gamma pass rates with 3%/3mm dose difference/distance-to-agreement criteria ranged from 89.3% to 92.2%, compared to from 95.6% to 99.0% obtained with the commissioned system. The 3D gamma pass rate between the commissioned system and DFOS was 98.2%. The typical noise rates in DFOS reconstructions were up to 3%, compared to under 2% for the commissioned system. In conclusion, while the introduction of a solid tank proved advantageous with regards to cost and convenience, further work is required to improve the image quality and dose reconstruction accuracy of the new DFOS optical-CT system.

  10. Computer-assisted solid lung nodule 3D volumetry on CT : influence of scan mode and iterative reconstruction: a CT phantom study

    NARCIS (Netherlands)

    Coenen, Adriaan; Honda, Osamu; van der Jagt, Eric J.; Tomiyama, Noriyuki

    2013-01-01

    To evaluate the effect of high-resolution scan mode and iterative reconstruction on lung nodule 3D volumetry. Solid nodules with various sizes (5, 8, 10 and 12 mm) were placed inside a chest phantom. CT images were obtained with various tube currents, scan modes (conventional mode, high-resolution m

  11. 3D nonrigid medical image registration using a new information theoretic measure

    Science.gov (United States)

    Li, Bicao; Yang, Guanyu; Coatrieux, Jean Louis; Li, Baosheng; Shu, Huazhong

    2015-11-01

    This work presents a novel method for the nonrigid registration of medical images based on the Arimoto entropy, a generalization of the Shannon entropy. The proposed method employed the Jensen-Arimoto divergence measure as a similarity metric to measure the statistical dependence between medical images. Free-form deformations were adopted as the transformation model and the Parzen window estimation was applied to compute the probability distributions. A penalty term is incorporated into the objective function to smooth the nonrigid transformation. The goal of registration is to optimize an objective function consisting of a dissimilarity term and a penalty term, which would be minimal when two deformed images are perfectly aligned using the limited memory BFGS optimization method, and thus to get the optimal geometric transformation. To validate the performance of the proposed method, experiments on both simulated 3D brain MR images and real 3D thoracic CT data sets were designed and performed on the open source elastix package. For the simulated experiments, the registration errors of 3D brain MR images with various magnitudes of known deformations and different levels of noise were measured. For the real data tests, four data sets of 4D thoracic CT from four patients were selected to assess the registration performance of the method, including ten 3D CT images for each 4D CT data covering an entire respiration cycle. These results were compared with the normalized cross correlation and the mutual information methods and show a slight but true improvement in registration accuracy.

  12. Visualizing Vertebrate Embryos with Episcopic 3D Imaging Techniques

    Directory of Open Access Journals (Sweden)

    Stefan H. Geyer

    2009-01-01

    Full Text Available The creation of highly detailed, three-dimensional (3D computer models is essential in order to understand the evolution and development of vertebrate embryos, and the pathogenesis of hereditary diseases. A still-increasing number of methods allow for generating digital volume data sets as the basis of virtual 3D computer models. This work aims to provide a brief overview about modern volume data–generation techniques, focusing on episcopic 3D imaging methods. The technical principles, advantages, and problems of episcopic 3D imaging are described. The strengths and weaknesses in its ability to visualize embryo anatomy and labeled gene product patterns, specifically, are discussed.

  13. Compression of 3D integral images using wavelet decomposition

    Science.gov (United States)

    Mazri, Meriem; Aggoun, Amar

    2003-06-01

    This paper presents a wavelet-based lossy compression technique for unidirectional 3D integral images (UII). The method requires the extraction of different viewpoint images from the integral image. A single viewpoint image is constructed by extracting one pixel from each microlens, then each viewpoint image is decomposed using a Two Dimensional Discrete Wavelet Transform (2D-DWT). The resulting array of coefficients contains several frequency bands. The lower frequency bands of the viewpoint images are assembled and compressed using a 3 Dimensional Discrete Cosine Transform (3D-DCT) followed by Huffman coding. This will achieve decorrelation within and between 2D low frequency bands from the different viewpoint images. The remaining higher frequency bands are Arithmetic coded. After decoding and decompression of the viewpoint images using an inverse 3D-DCT and an inverse 2D-DWT, each pixel from every reconstructed viewpoint image is put back into its original position within the microlens to reconstruct the whole 3D integral image. Simulations were performed on a set of four different grey level 3D UII using a uniform scalar quantizer with deadzone. The results for the average of the four UII intensity distributions are presented and compared with previous use of 3D-DCT scheme. It was found that the algorithm achieves better rate-distortion performance, with respect to compression ratio and image quality at very low bit rates.

  14. Highway 3D model from image and lidar data

    Science.gov (United States)

    Chen, Jinfeng; Chu, Henry; Sun, Xiaoduan

    2014-05-01

    We present a new method of highway 3-D model construction developed based on feature extraction in highway images and LIDAR data. We describe the processing road coordinate data that connect the image frames to the coordinates of the elevation data. Image processing methods are used to extract sky, road, and ground regions as well as significant objects (such as signs and building fronts) in the roadside for the 3D model. LIDAR data are interpolated and processed to extract the road lanes as well as other features such as trees, ditches, and elevated objects to form the 3D model. 3D geometry reasoning is used to match the image features to the 3D model. Results from successive frames are integrated to improve the final model.

  15. Phase Sensitive Cueing for 3D Objects in Overhead Images

    Energy Technology Data Exchange (ETDEWEB)

    Paglieroni, D

    2005-02-04

    Locating specific 3D objects in overhead images is an important problem in many remote sensing applications. 3D objects may contain either one connected component or multiple disconnected components. Solutions must accommodate images acquired with diverse sensors at various times of the day, in various seasons of the year, or under various weather conditions. Moreover, the physical manifestation of a 3D object with fixed physical dimensions in an overhead image is highly dependent on object physical dimensions, object position/orientation, image spatial resolution, and imaging geometry (e.g., obliqueness). This paper describes a two-stage computer-assisted approach for locating 3D objects in overhead images. In the matching stage, the computer matches models of 3D objects to overhead images. The strongest degree of match over all object orientations is computed at each pixel. Unambiguous local maxima in the degree of match as a function of pixel location are then found. In the cueing stage, the computer sorts image thumbnails in descending order of figure-of-merit and presents them to human analysts for visual inspection and interpretation. The figure-of-merit associated with an image thumbnail is computed from the degrees of match to a 3D object model associated with unambiguous local maxima that lie within the thumbnail. This form of computer assistance is invaluable when most of the relevant thumbnails are highly ranked, and the amount of inspection time needed is much less for the highly ranked thumbnails than for images as a whole.

  16. 3D laser imaging for concealed object identification

    Science.gov (United States)

    Berechet, Ion; Berginc, Gérard; Berechet, Stefan

    2014-09-01

    This paper deals with new optical non-conventional 3D laser imaging. Optical non-conventional imaging explores the advantages of laser imaging to form a three-dimensional image of the scene. 3D laser imaging can be used for threedimensional medical imaging, topography, surveillance, robotic vision because of ability to detect and recognize objects. In this paper, we present a 3D laser imaging for concealed object identification. The objective of this new 3D laser imaging is to provide the user a complete 3D reconstruction of the concealed object from available 2D data limited in number and with low representativeness. The 2D laser data used in this paper come from simulations that are based on the calculation of the laser interactions with the different interfaces of the scene of interest and from experimental results. We show the global 3D reconstruction procedures capable to separate objects from foliage and reconstruct a threedimensional image of the considered object. In this paper, we present examples of reconstruction and completion of three-dimensional images and we analyse the different parameters of the identification process such as resolution, the scenario of camouflage, noise impact and lacunarity degree.

  17. Automated 3D renal segmentation based on image partitioning

    Science.gov (United States)

    Yeghiazaryan, Varduhi; Voiculescu, Irina D.

    2016-03-01

    Despite several decades of research into segmentation techniques, automated medical image segmentation is barely usable in a clinical context, and still at vast user time expense. This paper illustrates unsupervised organ segmentation through the use of a novel automated labelling approximation algorithm followed by a hypersurface front propagation method. The approximation stage relies on a pre-computed image partition forest obtained directly from CT scan data. We have implemented all procedures to operate directly on 3D volumes, rather than slice-by-slice, because our algorithms are dimensionality-independent. The results picture segmentations which identify kidneys, but can easily be extrapolated to other body parts. Quantitative analysis of our automated segmentation compared against hand-segmented gold standards indicates an average Dice similarity coefficient of 90%. Results were obtained over volumes of CT data with 9 kidneys, computing both volume-based similarity measures (such as the Dice and Jaccard coefficients, true positive volume fraction) and size-based measures (such as the relative volume difference). The analysis considered both healthy and diseased kidneys, although extreme pathological cases were excluded from the overall count. Such cases are difficult to segment both manually and automatically due to the large amplitude of Hounsfield unit distribution in the scan, and the wide spread of the tumorous tissue inside the abdomen. In the case of kidneys that have maintained their shape, the similarity range lies around the values obtained for inter-operator variability. Whilst the procedure is fully automated, our tools also provide a light level of manual editing.

  18. Fast, high-resolution 3D dosimetry utilizing a novel optical-CT scanner incorporating tertiary telecentric collimation

    OpenAIRE

    Sakhalkar, H. S.; Oldham, M

    2008-01-01

    This study introduces a charge coupled device (CCD) area detector based optical-computed tomography (optical-CT) scanner for comprehensive verification of radiation dose distributions recorded in nonscattering radiochromic dosimeters. Defining characteristics include: (i) a very fast scanning time of ~5 min to acquire a complete three-dimensional (3D) dataset, (ii) improved image formation through the use of custom telecentric optics, which ensures accurate projection images and minimizes art...

  19. Acoustic 3D imaging of dental structures

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, D.K. [Lawrence Livermore National Lab., CA (United States); Hume, W.R. [California Univ., Los Angeles, CA (United States); Douglass, G.D. [California Univ., San Francisco, CA (United States)

    1997-02-01

    Our goals for the first year of this three dimensional electodynamic imaging project was to determine how to combine flexible, individual addressable; preprocessing of array source signals; spectral extrapolation or received signals; acoustic tomography codes; and acoustic propagation modeling code. We investigated flexible, individually addressable acoustic array material to find the best match in power, sensitivity and cost and settled on PVDF sheet arrays and 3-1 composite material.

  20. 3D/3D registration of coronary CTA and biplane XA reconstructions for improved image guidance

    Energy Technology Data Exchange (ETDEWEB)

    Dibildox, Gerardo, E-mail: g.dibildox@erasmusmc.nl; Baka, Nora; Walsum, Theo van [Biomedical Imaging Group Rotterdam, Departments of Radiology and Medical Informatics, Erasmus Medical Center, 3015 GE Rotterdam (Netherlands); Punt, Mark; Aben, Jean-Paul [Pie Medical Imaging, 6227 AJ Maastricht (Netherlands); Schultz, Carl [Department of Cardiology, Erasmus Medical Center, 3015 GE Rotterdam (Netherlands); Niessen, Wiro [Quantitative Imaging Group, Faculty of Applied Sciences, Delft University of Technology, 2628 CJ Delft, The Netherlands and Biomedical Imaging Group Rotterdam, Departments of Radiology and Medical Informatics, Erasmus Medical Center, 3015 GE Rotterdam (Netherlands)

    2014-09-15

    Purpose: The authors aim to improve image guidance during percutaneous coronary interventions of chronic total occlusions (CTO) by providing information obtained from computed tomography angiography (CTA) to the cardiac interventionist. To this end, the authors investigate a method to register a 3D CTA model to biplane reconstructions. Methods: The authors developed a method for registering preoperative coronary CTA with intraoperative biplane x-ray angiography (XA) images via 3D models of the coronary arteries. The models are extracted from the CTA and biplane XA images, and are temporally aligned based on CTA reconstruction phase and XA ECG signals. Rigid spatial alignment is achieved with a robust probabilistic point set registration approach using Gaussian mixture models (GMMs). This approach is extended by including orientation in the Gaussian mixtures and by weighting bifurcation points. The method is evaluated on retrospectively acquired coronary CTA datasets of 23 CTO patients for which biplane XA images are available. Results: The Gaussian mixture model approach achieved a median registration accuracy of 1.7 mm. The extended GMM approach including orientation was not significantly different (P > 0.1) but did improve robustness with regards to the initialization of the 3D models. Conclusions: The authors demonstrated that the GMM approach can effectively be applied to register CTA to biplane XA images for the purpose of improving image guidance in percutaneous coronary interventions.

  1. 3D soft tissue imaging with a mobile C-arm.

    Science.gov (United States)

    Ritter, Dieter; Orman, Jasmina; Schmidgunst, Christian; Graumann, Rainer

    2007-03-01

    We introduce a clinical prototype for 3D soft tissue imaging to support surgical or interventional procedures based on a mobile C-arm. An overview of required methods and materials is followed by first clinical images of animals and human patients including dosimetry. The mobility and flexibility of 3D C-arms gives free access to the patient and therefore avoids relocation of the patient between imaging and surgical intervention. Image fusion with diagnostic data (MRI, CT, PET) is demonstrated and promising applications for brachytherapy, RFTT and others are discussed.

  2. 3D X-ray imaging methods in support catheter ablations of cardiac arrhythmias.

    Science.gov (United States)

    Stárek, Zdeněk; Lehar, František; Jež, Jiří; Wolf, Jiří; Novák, Miroslav

    2014-10-01

    Cardiac arrhythmias are a very frequent illness. Pharmacotherapy is not very effective in persistent arrhythmias and brings along a number of risks. Catheter ablation has became an effective and curative treatment method over the past 20 years. To support complex arrhythmia ablations, the 3D X-ray cardiac cavities imaging is used, most frequently the 3D reconstruction of CT images. The 3D cardiac rotational angiography (3DRA) represents a modern method enabling to create CT like 3D images on a standard X-ray machine equipped with special software. Its advantage lies in the possibility to obtain images during the procedure, decreased radiation dose and reduction of amount of the contrast agent. The left atrium model is the one most frequently used for complex atrial arrhythmia ablations, particularly for atrial fibrillation. CT data allow for creation and segmentation of 3D models of all cardiac cavities. Recently, a research has been made proving the use of 3DRA to create 3D models of other cardiac (right ventricle, left ventricle, aorta) and non-cardiac structures (oesophagus). They can be used during catheter ablation of complex arrhythmias to improve orientation during the construction of 3D electroanatomic maps, directly fused with 3D electroanatomic systems and/or fused with fluoroscopy. An intensive development in the 3D model creation and use has taken place over the past years and they became routinely used during catheter ablations of arrhythmias, mainly atrial fibrillation ablation procedures. Further development may be anticipated in the future in both the creation and use of these models.

  3. Reconstruction of High Resolution 3D Objects from Incomplete Images and 3D Information

    Directory of Open Access Journals (Sweden)

    Alexander Pacheco

    2014-05-01

    Full Text Available To this day, digital object reconstruction is a quite complex area that requires many techniques and novel approaches, in which high-resolution 3D objects present one of the biggest challenges. There are mainly two different methods that can be used to reconstruct high resolution objects and images: passive methods and active methods. This methods depend on the type of information available as input for modeling 3D objects. The passive methods use information contained in the images and the active methods make use of controlled light sources, such as lasers. The reconstruction of 3D objects is quite complex and there is no unique solution- The use of specific methodologies for the reconstruction of certain objects it’s also very common, such as human faces, molecular structures, etc. This paper proposes a novel hybrid methodology, composed by 10 phases that combine active and passive methods, using images and a laser in order to supplement the missing information and obtain better results in the 3D object reconstruction. Finally, the proposed methodology proved its efficiency in two complex topological complex objects.

  4. Micro-CT studies on 3-D bioactive glass-ceramic scaffolds for bone regeneration.

    Science.gov (United States)

    Renghini, Chiara; Komlev, Vladimir; Fiori, Fabrizio; Verné, Enrica; Baino, Francesco; Vitale-Brovarone, Chiara

    2009-05-01

    The aim of this study was the preparation and characterization of bioactive glass-ceramic scaffolds for bone tissue engineering. For this purpose, a glass belonging to the system SiO2-P2O5-CaO-MgO-Na2O-K2O (CEL2) was used. The sponge-replication method was adopted to prepare the scaffolds; specifically, a polymeric skeleton was impregnated with a slurry containing CEL2 powder, polyvinyl alcohol (PVA) as a binding agent and distilled water. The impregnated sponge was then thermally treated to remove the polymeric phase and to sinter the inorganic one. The obtained scaffolds possessed an open and interconnected porosity, analogous to cancellous bone texture, and with a mechanical strength above 2 MPa. Moreover, the scaffolds underwent partial bioresorption due to ion-leaching phenomena. This feature was investigated by X-ray computed microcomputed tomography (micro-CT). Micro-CT is a three-dimensional (3-D) radiographic imaging technique, able to achieve a spatial resolution close to 1 microm(3). The use of synchrotron radiation allows the selected photon energy to be tuned to optimize the contrast among the different phases in the investigated samples. The 3-D scaffolds were soaked in a simulated body fluid (SBF) to study the formation of hydroxyapatite microcrystals on the scaffold struts and on the internal pore walls. The 3-D scaffolds were also soaked in a buffer solution (Tris-HCl) for different times to assess the scaffold bioresorption according to the ISO standard. A gradual resorption of the pores walls was observed during the soakings both in SBF and in Tris-HCl.

  5. 3D Motion Parameters Determination Based on Binocular Sequence Images

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Exactly capturing three dimensional (3D) motion information of an object is an essential and important task in computer vision, and is also one of the most difficult problems. In this paper, a binocular vision system and a method for determining 3D motion parameters of an object from binocular sequence images are introduced. The main steps include camera calibration, the matching of motion and stereo images, 3D feature point correspondences and resolving the motion parameters. Finally, the experimental results of acquiring the motion parameters of the objects with uniform velocity and acceleration in the straight line based on the real binocular sequence images by the mentioned method are presented.

  6. 3D Shape Indexing and Retrieval Using Characteristics level images

    Directory of Open Access Journals (Sweden)

    Abdelghni Lakehal

    2012-05-01

    Full Text Available In this paper, we propose an improved version of the descriptor that we proposed before. The descriptor is based on a set of binary images extracted from the 3D model called level images noted LI. The set LI is often bulky, why we introduced the X-means technique to reduce its size instead of K-means used in the old version. A 2D binary image descriptor was introduced to extract the vectors descriptors of the 3D model. For a comparative study of two versions of the descriptor, we used the National Taiwan University (NTU database of 3D object.

  7. Peripheral pulmonary arteries: identification at multi-slice spiral CT with 3D reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Coche, Emmanuel; Pawlak, Sebastien; Dechambre, Stephane; Maldague, Baudouin [Department of Radiology, St. Luc Hospital, UCL, Avenue Hippocrate, 10, 1200 Brussels (Belgium)

    2003-04-01

    Our objective was to analyze the peripheral pulmonary arteries using thin-collimation multi-slice spiral CT. Twenty consecutive patients underwent enhanced-spiral multi-slice CT using 1-mm collimation. Two observers analyzed the pulmonary arteries by consensus on a workstation. Each artery was identified on axial and 3D shaded-surface display reconstruction images. Each subsegmental artery was measured at a mediastinal window setting and compared with anatomical classifications. The location and branching of every subsegmental artery was recorded. The number of well-visualized sub-subsegmental arteries at a mediastinal window setting was compared with those visualized at a lung window setting. Of 800 subsegmental arteries, 769 (96%) were correctly visualized and 123 accessory subsegmental arteries were identified using the mediastinal window setting. One thousand ninety-two of 2019 sub-subsegmental arteries (54%) identified using the lung window setting were correctly visualized using the mediastinal window setting. Enhanced multi-slice spiral CT with thin collimation can be used to analyze precisely the subsegmental pulmonary arteries and may identify even more distal pulmonary arteries. (orig.)

  8. Peripheral pulmonary arteries: identification at multi-slice spiral CT with 3D reconstruction.

    Science.gov (United States)

    Coche, Emmanuel; Pawlak, Sebastien; Dechambre, Stéphane; Maldague, Baudouin

    2003-04-01

    Our objective was to analyze the peripheral pulmonary arteries using thin-collimation multi-slice spiral CT. Twenty consecutive patients underwent enhanced-spiral multi-slice CT using 1-mm collimation. Two observers analyzed the pulmonary arteries by consensus on a workstation. Each artery was identified on axial and 3D shaded-surface display reconstruction images. Each subsegmental artery was measured at a mediastinal window setting and compared with anatomical classifications. The location and branching of every subsegmental artery was recorded. The number of well-visualized sub-subsegmental arteries at a mediastinal window setting was compared with those visualized at a lung window setting. Of 800 subsegmental arteries, 769 (96%) were correctly visualized and 123 accessory subsegmental arteries were identified using the mediastinal window setting. One thousand ninety-two of 2019 sub-subsegmental arteries (54%) identified using the lung window setting were correctly visualized using the mediastinal window setting. Enhanced multi-slice spiral CT with thin collimation can be used to analyze precisely the subsegmental pulmonary arteries and may identify even more distal pulmonary arteries.

  9. Potential Cost Savings with 3D Printing Combined With 3D Imaging and CPLM for Fleet Maintenance and Revitalization

    Science.gov (United States)

    2014-05-01

    1 Potential Cost Savings with 3D Printing Combined With 3D Imaging and CPLM for Fleet Maintenance and Revitalization David N. Ford...2014 4. TITLE AND SUBTITLE Potential Cost Savings with 3D Printing Combined With 3D Imaging and CPLM for Fleet Maintenance and Revitalization 5a...Manufacturing ( 3D printing ) 2 Research Context Problem: Learning curve savings forecasted in SHIPMAIN maintenance initiative have not materialized

  10. Preliminary examples of 3D vector flow imaging

    DEFF Research Database (Denmark)

    Pihl, Michael Johannes; Stuart, Matthias Bo; Tomov, Borislav Gueorguiev

    2013-01-01

    This paper presents 3D vector flow images obtained using the 3D Transverse Oscillation (TO) method. The method employs a 2D transducer and estimates the three velocity components simultaneously, which is important for visualizing complex flow patterns. Data are acquired using the experimental ult...

  11. Technical Note: Characterization of custom 3D printed multimodality imaging phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Bieniosek, Matthew F. [Department of Electrical Engineering, Stanford University, 350 Serra Mall, Stanford, California 94305 (United States); Lee, Brian J. [Department of Mechanical Engineering, Stanford University, 440 Escondido Mall, Stanford, California 94305 (United States); Levin, Craig S., E-mail: cslevin@stanford.edu [Departments of Radiology, Physics, Bioengineering and Electrical Engineering, Stanford University, 300 Pasteur Dr., Stanford, California 94305-5128 (United States)

    2015-10-15

    Purpose: Imaging phantoms are important tools for researchers and technicians, but they can be costly and difficult to customize. Three dimensional (3D) printing is a widely available rapid prototyping technique that enables the fabrication of objects with 3D computer generated geometries. It is ideal for quickly producing customized, low cost, multimodal, reusable imaging phantoms. This work validates the use of 3D printed phantoms by comparing CT and PET scans of a 3D printed phantom and a commercial “Micro Deluxe” phantom. This report also presents results from a customized 3D printed PET/MRI phantom, and a customized high resolution imaging phantom with sub-mm features. Methods: CT and PET scans of a 3D printed phantom and a commercial Micro Deluxe (Data Spectrum Corporation, USA) phantom with 1.2, 1.6, 2.4, 3.2, 4.0, and 4.8 mm diameter hot rods were acquired. The measured PET and CT rod sizes, activities, and attenuation coefficients were compared. A PET/MRI scan of a custom 3D printed phantom with hot and cold rods was performed, with photon attenuation and normalization measurements performed with a separate 3D printed normalization phantom. X-ray transmission scans of a customized two level high resolution 3D printed phantom with sub-mm features were also performed. Results: Results show very good agreement between commercial and 3D printed micro deluxe phantoms with less than 3% difference in CT measured rod diameter, less than 5% difference in PET measured rod diameter, and a maximum of 6.2% difference in average rod activity from a 10 min, 333 kBq/ml (9 μCi/ml) Siemens Inveon (Siemens Healthcare, Germany) PET scan. In all cases, these differences were within the measurement uncertainties of our setups. PET/MRI scans successfully identified 3D printed hot and cold rods on PET and MRI modalities. X-ray projection images of a 3D printed high resolution phantom identified features as small as 350 μm wide. Conclusions: This work shows that 3D printed

  12. 3D quantitative phase imaging of neural networks using WDT

    Science.gov (United States)

    Kim, Taewoo; Liu, S. C.; Iyer, Raj; Gillette, Martha U.; Popescu, Gabriel

    2015-03-01

    White-light diffraction tomography (WDT) is a recently developed 3D imaging technique based on a quantitative phase imaging system called spatial light interference microscopy (SLIM). The technique has achieved a sub-micron resolution in all three directions with high sensitivity granted by the low-coherence of a white-light source. Demonstrations of the technique on single cell imaging have been presented previously; however, imaging on any larger sample, including a cluster of cells, has not been demonstrated using the technique. Neurons in an animal body form a highly complex and spatially organized 3D structure, which can be characterized by neuronal networks or circuits. Currently, the most common method of studying the 3D structure of neuron networks is by using a confocal fluorescence microscope, which requires fluorescence tagging with either transient membrane dyes or after fixation of the cells. Therefore, studies on neurons are often limited to samples that are chemically treated and/or dead. WDT presents a solution for imaging live neuron networks with a high spatial and temporal resolution, because it is a 3D imaging method that is label-free and non-invasive. Using this method, a mouse or rat hippocampal neuron culture and a mouse dorsal root ganglion (DRG) neuron culture have been imaged in order to see the extension of processes between the cells in 3D. Furthermore, the tomogram is compared with a confocal fluorescence image in order to investigate the 3D structure at synapses.

  13. Image based 3D city modeling : Comparative study

    Science.gov (United States)

    Singh, S. P.; Jain, K.; Mandla, V. R.

    2014-06-01

    3D city model is a digital representation of the Earth's surface and it's related objects such as building, tree, vegetation, and some manmade feature belonging to urban area. The demand of 3D city modeling is increasing rapidly for various engineering and non-engineering applications. Generally four main image based approaches were used for virtual 3D city models generation. In first approach, researchers were used Sketch based modeling, second method is Procedural grammar based modeling, third approach is Close range photogrammetry based modeling and fourth approach is mainly based on Computer Vision techniques. SketchUp, CityEngine, Photomodeler and Agisoft Photoscan are the main softwares to represent these approaches respectively. These softwares have different approaches & methods suitable for image based 3D city modeling. Literature study shows that till date, there is no complete such type of comparative study available to create complete 3D city model by using images. This paper gives a comparative assessment of these four image based 3D modeling approaches. This comparative study is mainly based on data acquisition methods, data processing techniques and output 3D model products. For this research work, study area is the campus of civil engineering department, Indian Institute of Technology, Roorkee (India). This 3D campus acts as a prototype for city. This study also explains various governing parameters, factors and work experiences. This research work also gives a brief introduction, strengths and weakness of these four image based techniques. Some personal comment is also given as what can do or what can't do from these softwares. At the last, this study shows; it concluded that, each and every software has some advantages and limitations. Choice of software depends on user requirements of 3D project. For normal visualization project, SketchUp software is a good option. For 3D documentation record, Photomodeler gives good result. For Large city

  14. A colour image reproduction framework for 3D colour printing

    Science.gov (United States)

    Xiao, Kaida; Sohiab, Ali; Sun, Pei-li; Yates, Julian M.; Li, Changjun; Wuerger, Sophie

    2016-10-01

    In this paper, the current technologies in full colour 3D printing technology were introduced. A framework of colour image reproduction process for 3D colour printing is proposed. A special focus was put on colour management for 3D printed objects. Two approaches, colorimetric colour reproduction and spectral based colour reproduction are proposed in order to faithfully reproduce colours in 3D objects. Two key studies, colour reproduction for soft tissue prostheses and colour uniformity correction across different orientations are described subsequently. Results are clear shown that applying proposed colour image reproduction framework, performance of colour reproduction can be significantly enhanced. With post colour corrections, a further improvement in colour process are achieved for 3D printed objects.

  15. ImageJ软件在三维立体CT图像处理中的应用%Application of 3D CT Image Processing Based on ImageJ

    Institute of Scientific and Technical Information of China (English)

    张培; 李梦洁; 孙水发; 黄志勇

    2012-01-01

    通过使用ImageJ这款开放源代码的图像处理软件对一组人头部颅内的CT切片进行处理,着重介绍了ImageJ在三维CT图像处理中的应用.给出了ImageJ进行三维CT图像处理主要的操作方法和处理后的效果图,为更好地使用ImageJ对CT图像进行三维处理提供参考.通过先计算各个感兴趣区域的面积,再累加实现了三维模型体积的计算.如果进一步知道图像的物理分辨率及CT切片的物理间距,则可以计算出感兴趣目标真实体积.

  16. 3D Image Modelling and Specific Treatments in Orthodontics Domain

    Directory of Open Access Journals (Sweden)

    Dionysis Goularas

    2007-01-01

    Full Text Available In this article, we present a 3D specific dental plaster treatment system for orthodontics. From computer tomography scanner images, we propose first a 3D image modelling and reconstruction method of the Mandible and Maxillary based on an adaptive triangulation allowing management of contours meant for the complex topologies. Secondly, we present two specific treatment methods directly achieved on obtained 3D model allowing the automatic correction for the setting in occlusion of the Mandible and the Maxillary, and the teeth segmentation allowing more specific dental examinations. Finally, these specific treatments are presented via a client/server application with the aim of allowing a telediagnosis and treatment.

  17. Imaging fault zones using 3D seismic image processing techniques

    Science.gov (United States)

    Iacopini, David; Butler, Rob; Purves, Steve

    2013-04-01

    Significant advances in structural analysis of deep water structure, salt tectonic and extensional rift basin come from the descriptions of fault system geometries imaged in 3D seismic data. However, even where seismic data are excellent, in most cases the trajectory of thrust faults is highly conjectural and still significant uncertainty exists as to the patterns of deformation that develop between the main faults segments, and even of the fault architectures themselves. Moreover structural interpretations that conventionally define faults by breaks and apparent offsets of seismic reflectors are commonly conditioned by a narrow range of theoretical models of fault behavior. For example, almost all interpretations of thrust geometries on seismic data rely on theoretical "end-member" behaviors where concepts as strain localization or multilayer mechanics are simply avoided. Yet analogue outcrop studies confirm that such descriptions are commonly unsatisfactory and incomplete. In order to fill these gaps and improve the 3D visualization of deformation in the subsurface, seismic attribute methods are developed here in conjunction with conventional mapping of reflector amplitudes (Marfurt & Chopra, 2007)). These signal processing techniques recently developed and applied especially by the oil industry use variations in the amplitude and phase of the seismic wavelet. These seismic attributes improve the signal interpretation and are calculated and applied to the entire 3D seismic dataset. In this contribution we will show 3D seismic examples of fault structures from gravity-driven deep-water thrust structures and extensional basin systems to indicate how 3D seismic image processing methods can not only build better the geometrical interpretations of the faults but also begin to map both strain and damage through amplitude/phase properties of the seismic signal. This is done by quantifying and delineating the short-range anomalies on the intensity of reflector amplitudes

  18. 3D weighting in cone beam image reconstruction algorithms: ray-driven vs. pixel-driven.

    Science.gov (United States)

    Tang, Xiangyang; Nilsen, Roy A; Smolin, Alex; Lifland, Ilya; Samsonov, Dmitry; Taha, Basel

    2008-01-01

    A 3D weighting scheme have been proposed previously to reconstruct images at both helical and axial scans in stat-of-the-art volumetric CT scanners for diagnostic imaging. Such a 3D weighting can be implemented in the manner of either ray-driven or pixel-drive, depending on the available computation resources. An experimental study is conducted in this paper to evaluate the difference between the ray-driven and pixel-driven implementations of the 3D weighting from the perspective of image quality, while their computational complexity is analyzed theoretically. Computer simulated data and several phantoms, such as the helical body phantom and humanoid chest phantom, are employed in the experimental study, showing that both the ray-driven and pixel-driven 3D weighting provides superior image quality for diagnostic imaging in clinical applications. With the availability of image reconstruction engine at increasing computational power, it is believed that the pixel-driven 3D weighting will be dominantly employed in state-of-the-art volumetric CT scanners over clinical applications.

  19. Mixed reality orthognathic surgical simulation by entity model manipulation and 3D-image display

    Science.gov (United States)

    Shimonagayoshi, Tatsunari; Aoki, Yoshimitsu; Fushima, Kenji; Kobayashi, Masaru

    2005-12-01

    In orthognathic surgery, the framing of 3D-surgical planning that considers the balance between the front and back positions and the symmetry of the jawbone, as well as the dental occlusion of teeth, is essential. In this study, a support system for orthodontic surgery to visualize the changes in the mandible and the occlusal condition and to determine the optimum position in mandibular osteotomy has been developed. By integrating the operating portion of a tooth model that is to determine the optimum occlusal position by manipulating the entity tooth model and the 3D-CT skeletal images (3D image display portion) that are simultaneously displayed in real-time, the determination of the mandibular position and posture in which the improvement of skeletal morphology and occlusal condition is considered, is possible. The realistic operation of the entity model and the virtual 3D image display enabled the construction of a surgical simulation system that involves augmented reality.

  20. Fully Automatic 3D Reconstruction of Histological Images

    CERN Document Server

    Bagci, Ulas

    2009-01-01

    In this paper, we propose a computational framework for 3D volume reconstruction from 2D histological slices using registration algorithms in feature space. To improve the quality of reconstructed 3D volume, first, intensity variations in images are corrected by an intensity standardization process which maps image intensity scale to a standard scale where similar intensities correspond to similar tissues. Second, a subvolume approach is proposed for 3D reconstruction by dividing standardized slices into groups. Third, in order to improve the quality of the reconstruction process, an automatic best reference slice selection algorithm is developed based on an iterative assessment of image entropy and mean square error of the registration process. Finally, we demonstrate that the choice of the reference slice has a significant impact on registration quality and subsequent 3D reconstruction.

  1. Progresses in 3D integral imaging with optical processing

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Corral, Manuel; Martinez-Cuenca, Raul; Saavedra, Genaro; Navarro, Hector; Pons, Amparo [Department of Optics. University of Valencia. Calle Doctor Moliner 50, E46 100, Burjassot (Spain); Javidi, Bahram [Electrical and Computer Engineering Department, University of Connecticut, Storrs, CT 06269-1157 (United States)], E-mail: manuel.martinez@uv.es

    2008-11-01

    Integral imaging is a promising technique for the acquisition and auto-stereoscopic display of 3D scenes with full parallax and without the need of any additional devices like special glasses. First suggested by Lippmann in the beginning of the 20th century, integral imaging is based in the intersection of ray cones emitted by a collection of 2D elemental images which store the 3D information of the scene. This paper is devoted to the study, from the ray optics point of view, of the optical effects and interaction with the observer of integral imaging systems.

  2. DCT and DST Based Image Compression for 3D Reconstruction

    Science.gov (United States)

    Siddeq, Mohammed M.; Rodrigues, Marcos A.

    2017-03-01

    This paper introduces a new method for 2D image compression whose quality is demonstrated through accurate 3D reconstruction using structured light techniques and 3D reconstruction from multiple viewpoints. The method is based on two discrete transforms: (1) A one-dimensional Discrete Cosine Transform (DCT) is applied to each row of the image. (2) The output from the previous step is transformed again by a one-dimensional Discrete Sine Transform (DST), which is applied to each column of data generating new sets of high-frequency components followed by quantization of the higher frequencies. The output is then divided into two parts where the low-frequency components are compressed by arithmetic coding and the high frequency ones by an efficient minimization encoding algorithm. At decompression stage, a binary search algorithm is used to recover the original high frequency components. The technique is demonstrated by compressing 2D images up to 99% compression ratio. The decompressed images, which include images with structured light patterns for 3D reconstruction and from multiple viewpoints, are of high perceptual quality yielding accurate 3D reconstruction. Perceptual assessment and objective quality of compression are compared with JPEG and JPEG2000 through 2D and 3D RMSE. Results show that the proposed compression method is superior to both JPEG and JPEG2000 concerning 3D reconstruction, and with equivalent perceptual quality to JPEG2000.

  3. 3D Printing of CT Dataset: Validation of an Open Source and Consumer-Available Workflow.

    Science.gov (United States)

    Bortolotto, Chandra; Eshja, Esmeralda; Peroni, Caterina; Orlandi, Matteo A; Bizzotto, Nicola; Poggi, Paolo

    2016-02-01

    The broad availability of cheap three-dimensional (3D) printing equipment has raised the need for a thorough analysis on its effects on clinical accuracy. Our aim is to determine whether the accuracy of 3D printing process is affected by the use of a low-budget workflow based on open source software and consumer's commercially available 3D printers. A group of test objects was scanned with a 64-slice computed tomography (CT) in order to build their 3D copies. CT datasets were elaborated using a software chain based on three free and open source software. Objects were printed out with a commercially available 3D printer. Both the 3D copies and the test objects were measured using a digital professional caliper. Overall, the objects' mean absolute difference between test objects and 3D copies is 0.23 mm and the mean relative difference amounts to 0.55 %. Our results demonstrate that the accuracy of 3D printing process remains high despite the use of a low-budget workflow.

  4. Intraosseous rotation of the scaphoid: assessment by using a 3D CT model - an anatomic study

    Energy Technology Data Exchange (ETDEWEB)

    Schmidle, Gernot; Gabl, Markus [Medical University Innsbruck, Department of Trauma Surgery, Innsbruck (Austria); Rieger, Michael [Regional Hospital Hall, Department of Radiology, Hall in Tirol (Austria); Klauser, Andrea Sabine; Thauerer, Michael [Medical University Innsbruck, Department of Radiology, Innsbruck (Austria); Hoermann, Romed [Medical University Innsbruck, Department of Anatomy, Histology and Embryology-Division of Clinical and Functional Anatomy, Innsbruck (Austria)

    2014-06-15

    The purpose of this study was to assess intraosseous rotation as the third dimension of scaphoid anatomy on a 3D CT model using common volume rendering software to impact anatomical reconstruction of scaphoid fractures. CT images of 13 cadaver wrist pairs were acquired. Reference axes for the alignment of distal and proximal scaphoid poles were defined three-dimensionally. Two methods for rotation measurement - the reference axis method (RAM) and the scapho-trapezio-trapezoidal joint method (STTM) - were developed and compared by three independent observers. Rotation measured by the RAM averaged 66.9 ± 7 for the right and 67.2 ± 5.8 for the left wrists. Using the STTM there was a mean rotation of 68.6 ± 6.6 for the right and 68.6 ± 6.8 for the left wrists. The overall results showed a significant variability of the measured values between different specimens (P < 0.05). There was no significant difference between left and right wrists of the same specimen, neither for the RAM (P = 0.268) nor for the STTM (P = 0.774). Repeatability coefficients between the observers were low, indicating good repeatability. The presented methods are practical tools to quantify intraosseous rotation between distal and proximal scaphoid poles using common volume rendering software. For clinical application the opposite side provides the best reference values to assess malrotation in scaphoid fracture cases. (orig.)

  5. 3D Kidney Segmentation from Abdominal Images Using Spatial-Appearance Models

    Science.gov (United States)

    Khalifa, Fahmi; Soliman, Ahmed; Gimel'farb, Georgy

    2017-01-01

    Kidney segmentation is an essential step in developing any noninvasive computer-assisted diagnostic system for renal function assessment. This paper introduces an automated framework for 3D kidney segmentation from dynamic computed tomography (CT) images that integrates discriminative features from the current and prior CT appearances into a random forest classification approach. To account for CT images' inhomogeneities, we employ discriminate features that are extracted from a higher-order spatial model and an adaptive shape model in addition to the first-order CT appearance. To model the interactions between CT data voxels, we employed a higher-order spatial model, which adds the triple and quad clique families to the traditional pairwise clique family. The kidney shape prior model is built using a set of training CT data and is updated during segmentation using not only region labels but also voxels' appearances in neighboring spatial voxel locations. Our framework performance has been evaluated on in vivo dynamic CT data collected from 20 subjects and comprises multiple 3D scans acquired before and after contrast medium administration. Quantitative evaluation between manually and automatically segmented kidney contours using Dice similarity, percentage volume differences, and 95th-percentile bidirectional Hausdorff distances confirms the high accuracy of our approach.

  6. A 3D surface imaging system for assessing human obesity

    Science.gov (United States)

    Xu, B.; Yu, W.; Yao, M.; Yao, X.; Li, Q.; Pepper, M. R.; Freeland-Graves, J. H.

    2009-08-01

    The increasing prevalence of obesity suggests a need to develop a convenient, reliable and economical tool for assessment of this condition. Three-dimensional (3D) body surface imaging has emerged as an exciting technology for estimation of body composition. This paper presents a new 3D body imaging system, which was designed for enhanced portability, affordability, and functionality. In this system, stereo vision technology was used to satisfy the requirements for a simple hardware setup and fast image acquisitions. The portability of the system was created via a two-stand configuration, and the accuracy of body volume measurements was improved by customizing stereo matching and surface reconstruction algorithms that target specific problems in 3D body imaging. Body measurement functions dedicated to body composition assessment also were developed. The overall performance of the system was evaluated in human subjects by comparison to other conventional anthropometric methods, as well as air displacement plethysmography, for body fat assessment.

  7. 3D Medical Image Segmentation Based on Rough Set Theory

    Institute of Scientific and Technical Information of China (English)

    CHEN Shi-hao; TIAN Yun; WANG Yi; HAO Chong-yang

    2007-01-01

    This paper presents a method which uses multiple types of expert knowledge together in 3D medical image segmentation based on rough set theory. The focus of this paper is how to approximate a ROI (region of interest) when there are multiple types of expert knowledge. Based on rough set theory, the image can be split into three regions:positive regions; negative regions; boundary regions. With multiple knowledge we refine ROI as an intersection of all of the expected shapes with single knowledge. At last we show the results of implementing a rough 3D image segmentation and visualization system.

  8. 3D Images of Materials Structures Processing and Analysis

    CERN Document Server

    Ohser, Joachim

    2009-01-01

    Taking and analyzing images of materials' microstructures is essential for quality control, choice and design of all kind of products. Today, the standard method still is to analyze 2D microscopy images. But, insight into the 3D geometry of the microstructure of materials and measuring its characteristics become more and more prerequisites in order to choose and design advanced materials according to desired product properties. This first book on processing and analysis of 3D images of materials structures describes how to develop and apply efficient and versatile tools for geometric analysis

  9. A Texture Analysis of 3D Radar Images

    NARCIS (Netherlands)

    Deiana, D.; Yarovoy, A.

    2009-01-01

    In this paper a texture feature coding method to be applied to high-resolution 3D radar images in order to improve target detection is developed. An automatic method for image segmentation based on texture features is proposed. The method has been able to automatically detect weak targets which fail

  10. A prototype fan-beam optical CT scanner for 3D dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Warren G.; Rudko, D. A.; Braam, Nicolas A.; Jirasek, Andrew [University of Victoria, Victoria, British Columbia V8P 5C2 (Canada); Wells, Derek M. [British Columbia Cancer Agency, Vancouver Island Centre, Victoria, British Columbia V8R 6V5 (Canada)

    2013-06-15

    flask registration technique was shown to achieve submillimetre and subdegree placement accuracy. Dosimetry protocol investigations emphasize the need to allow gel dosimeters to cool gradually and to be scanned while at room temperature. Preliminary tests show that considerable noise reduction can be achieved with sinogram filtering and by binning image pixels into more clinically relevant grid sizes. Conclusions: This paper describes a new optical CT scanner for 3D radiation dosimetry. Tests demonstrate that it is capable of imaging both absorption-based and scatter-based samples of high opacities. Imaging protocol and gel dosimeter manufacture techniques have been adapted to produce optimal reconstruction results. These optimal results will require suitable filtering and binning techniques for noise reduction purposes.

  11. Visualising, segmenting and analysing heterogenous glacigenic sediments using 3D x-ray CT.

    Science.gov (United States)

    Carr, Simon; Diggens, Lucy; Groves, John; O'Sullivan, Catherine; Marsland, Rhona

    2015-04-01

    , especially with regard to using such data to improve understanding of mechanisms of particle motion and fabric development during subglacial strain. In this study, we present detailed investigation of subglacial tills from the UK, Iceland and Poland, to explore the challenges in segmenting these highly variable sediment bodies for 3D microfabric analysis. A calibration study is reported to compare various approaches to CT data segmentation to manually segmented datasets, from which an optimal workflow is developed, using a combination of the WEKA Trainable Segmentation tool within ImageJ to segment the data, followed by object-based analysis using Blob3D. We then demonstrate the value of this analysis through the analysis of true 3D microfabric data from a Last Glacial Maximum till deposit located at Morston, North Norfolk. Seven undisturbed sediment samples were scanned and analysed using high-resolution 3D X-ray computed tomography. Large (~5,000 to ~16,000) populations of individual particles are objectively and systematically segmented and identified. These large datasets are then subject to detailed interrogation using bespoke code for analysing particle fabric within Matlab, including the application of fabric-tensor analysis, by which fabrics can be weighted and scaled by key variables such as size and shape. We will present initial findings from these datasets, focusing particularly on overcoming the methodological challenges of obtaining robust datasets of sediments with highly complex, mixed compositional sediments.

  12. Automatic masking for robust 3D-2D image registration in image-guided spine surgery

    Science.gov (United States)

    Ketcha, M. D.; De Silva, T.; Uneri, A.; Kleinszig, G.; Vogt, S.; Wolinsky, J.-P.; Siewerdsen, J. H.

    2016-03-01

    During spinal neurosurgery, patient-specific information, planning, and annotation such as vertebral labels can be mapped from preoperative 3D CT to intraoperative 2D radiographs via image-based 3D-2D registration. Such registration has been shown to provide a potentially valuable means of decision support in target localization as well as quality assurance of the surgical product. However, robust registration can be challenged by mismatch in image content between the preoperative CT and intraoperative radiographs, arising, for example, from anatomical deformation or the presence of surgical tools within the radiograph. In this work, we develop and evaluate methods for automatically mitigating the effect of content mismatch by leveraging the surgical planning data to assign greater weight to anatomical regions known to be reliable for registration and vital to the surgical task while removing problematic regions that are highly deformable or often occluded by surgical tools. We investigated two approaches to assigning variable weight (i.e., "masking") to image content and/or the similarity metric: (1) masking the preoperative 3D CT ("volumetric masking"); and (2) masking within the 2D similarity metric calculation ("projection masking"). The accuracy of registration was evaluated in terms of projection distance error (PDE) in 61 cases selected from an IRB-approved clinical study. The best performing of the masking techniques was found to reduce the rate of gross failure (PDE > 20 mm) from 11.48% to 5.57% in this challenging retrospective data set. These approaches provided robustness to content mismatch and eliminated distinct failure modes of registration. Such improvement was gained without additional workflow and has motivated incorporation of the masking methods within a system under development for prospective clinical studies.

  13. DATA PROCESSING TECHNOLOGY OF AIRBORNE 3D IMAGE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Airborne 3D image which integrates GPS,attitude measurement unit (AMU),sca nning laser rangefinder (SLR) and spectral scanner has been developed successful ly.The spectral scanner and SLR use the same optical system which ensures laser point to match pixel seamlessly.The distinctive advantage of 3D image is that it can produce geo_referenced images and DSM (digital surface models) images wi thout any ground control points (GCPs).It is no longer necessary to sur vey GCPs and with some softwares the data can be processed and produce digital s urface models (DSM) and geo_referenced images in quasi_real_time,therefore,the efficiency of 3 D image is 10~100 times higher than that of traditional approaches.The process ing procedure involves decomposing and checking the raw data,processing GPS dat a,calculating the positions of laser sample points,producing geo_referenced im age,producing DSM and mosaicing strips.  The principle of 3D image is first introduced in this paper,and then we focus on the fast processing technique and algorithm.The flight tests and processed r esults show that the processing technique is feasible and can meet the requireme nt of quasi_real_time applications.

  14. Interactive visualization of multiresolution image stacks in 3D.

    Science.gov (United States)

    Trotts, Issac; Mikula, Shawn; Jones, Edward G

    2007-04-15

    Conventional microscopy, electron microscopy, and imaging techniques such as MRI and PET commonly generate large stacks of images of the sectioned brain. In other domains, such as neurophysiology, variables such as space or time are also varied along a stack axis. Digital image sizes have been progressively increasing and in virtual microscopy, it is now common to work with individual image sizes that are several hundred megapixels and several gigabytes in size. The interactive visualization of these high-resolution, multiresolution images in 2D has been addressed previously [Sullivan, G., and Baker, R., 1994. Efficient quad-tree coding of images and video. IEEE Trans. Image Process. 3 (3), 327-331]. Here, we describe a method for interactive visualization of multiresolution image stacks in 3D. The method, characterized as quad-tree based multiresolution image stack interactive visualization using a texel projection based criterion, relies on accessing and projecting image tiles from multiresolution image stacks in such a way that, from the observer's perspective, image tiles all appear approximately the same size even though they are accessed from different tiers within the images comprising the stack. This method enables efficient navigation of high-resolution image stacks. We implement this method in a program called StackVis, which is a Windows-based, interactive 3D multiresolution image stack visualization system written in C++ and using OpenGL. It is freely available at http://brainmaps.org.

  15. High Frame Rate Synthetic Aperture 3D Vector Flow Imaging

    DEFF Research Database (Denmark)

    Villagómez Hoyos, Carlos Armando; Holbek, Simon; Stuart, Matthias Bo

    2016-01-01

    3-D blood flow quantification with high spatial and temporal resolution would strongly benefit clinical research on cardiovascular pathologies. Ultrasonic velocity techniques are known for their ability to measure blood flow with high precision at high spatial and temporal resolution. However......, current volumetric ultrasonic flow methods are limited to one velocity component or restricted to a reduced field of view (FOV), e.g. fixed imaging planes, in exchange for higher temporal resolutions. To solve these problems, a previously proposed accurate 2-D high frame rate vector flow imaging (VFI......) technique is extended to estimate the 3-D velocity components inside a volume at high temporal resolutions (

  16. Image quality of a cone beam O-arm 3D imaging system

    Science.gov (United States)

    Zhang, Jie; Weir, Victor; Lin, Jingying; Hsiung, Hsiang; Ritenour, E. Russell

    2009-02-01

    The O-arm is a cone beam imaging system designed primarily to support orthopedic surgery and is also used for image-guided and vascular surgery. Using a gantry that can be opened or closed, the O-arm can function as a 2-dimensional (2D) fluoroscopy device or collect 3-dimensional (3D) volumetric imaging data like a CT system. Clinical applications of the O-arm in spine surgical procedures, assessment of pedicle screw position, and kyphoplasty procedures show that the O-arm 3D mode provides enhanced imaging information compared to radiographs or fluoroscopy alone. In this study, the image quality of an O-arm system was quantitatively evaluated. A 20 cm diameter CATPHAN 424 phantom was scanned using the pre-programmed head protocols: small/medium (120 kVp, 100 mAs), large (120 kVp, 128 mAs), and extra-large (120 kVp, 160 mAs) in 3D mode. High resolution reconstruction mode (512×512×0.83 mm) was used to reconstruct images for the analysis of low and high contrast resolution, and noise power spectrum. MTF was measured using the point spread function. The results show that the O-arm image is uniform but with a noise pattern which cannot be removed by simply increasing the mAs. The high contrast resolution of the O-arm system was approximately 9 lp/cm. The system has a 10% MTF at 0.45 mm. The low-contrast resolution cannot be decided due to the noise pattern. For surgery where locations of a structure are emphasized over a survey of all image details, the image quality of the O-arm is well accepted clinically.

  17. AUTOMATIC 3D MAPPING USING MULTIPLE UNCALIBRATED CLOSE RANGE IMAGES

    Directory of Open Access Journals (Sweden)

    M. Rafiei

    2013-09-01

    Full Text Available Automatic three-dimensions modeling of the real world is an important research topic in the geomatics and computer vision fields for many years. By development of commercial digital cameras and modern image processing techniques, close range photogrammetry is vastly utilized in many fields such as structure measurements, topographic surveying, architectural and archeological surveying, etc. A non-contact photogrammetry provides methods to determine 3D locations of objects from two-dimensional (2D images. Problem of estimating the locations of 3D points from multiple images, often involves simultaneously estimating both 3D geometry (structure and camera pose (motion, it is commonly known as structure from motion (SfM. In this research a step by step approach to generate the 3D point cloud of a scene is considered. After taking images with a camera, we should detect corresponding points in each two views. Here an efficient SIFT method is used for image matching for large baselines. After that, we must retrieve the camera motion and 3D position of the matched feature points up to a projective transformation (projective reconstruction. Lacking additional information on the camera or the scene makes the parallel lines to be unparalleled. The results of SfM computation are much more useful if a metric reconstruction is obtained. Therefor multiple views Euclidean reconstruction applied and discussed. To refine and achieve the precise 3D points we use more general and useful approach, namely bundle adjustment. At the end two real cases have been considered to reconstruct (an excavation and a tower.

  18. 3D CT modeling of hepatic vessel architecture and volume calculation in living donated liver transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Frericks, Bernd B. [Medizinische Hochschule Hannover, Diagnostische Radiologie, Hannover (Germany); Klinik und Poliklinik fuer Radiologie und Nuklearmedizin, Universitaetsklinikum Benjamin Franklin, Freie Universitaet Berlin, Hindenburgdamm 30, 12200, Berlin (Germany); Caldarone, Franco C.; Savellano, Dagmar Hoegemann; Stamm, Georg; Kirchhoff, Timm D.; Shin, Hoen-Oh; Galanski, Michael [Medizinische Hochschule Hannover, Diagnostische Radiologie, Hannover (Germany); Nashan, Bjoern; Klempnauer, Juergen [Medizinische Hochschule Hannover, Viszeral und Transplantationschirurgie, Hannover (Germany); Schenk, Andrea; Selle, Dirk; Spindler, Wolf; Peitgen, Heinz-Otto [Centrum fuer Medizinische Diagnosesysteme und Visualisierung, Bremen (Germany)

    2004-02-01

    The aim of this study was to evaluate a software tool for non-invasive preoperative volumetric assessment of potential donors in living donated liver transplantation (LDLT). Biphasic helical CT was performed in 56 potential donors. Data sets were post-processed using a non-commercial software tool for segmentation, volumetric analysis and visualisation of liver segments. Semi-automatic definition of liver margins allowed the segmentation of parenchyma. Hepatic vessels were delineated using a region-growing algorithm with automatically determined thresholds. Volumes and shapes of liver segments were calculated automatically based on individual portal-venous branches. Results were visualised three-dimensionally and statistically compared with conventional volumetry and the intraoperative findings in 27 transplanted cases. Image processing was easy to perform within 23 min. Of the 56 potential donors, 27 were excluded from LDLT because of inappropriate liver parenchyma or vascular architecture. Two recipients were not transplanted due to poor clinical conditions. In the 27 transplanted cases, preoperatively visualised vessels were confirmed, and only one undetected accessory hepatic vein was revealed. Calculated graft volumes were 1110{+-}180 ml for right lobes, 820 ml for the left lobe and 270{+-}30 ml for segments II+III. The calculated volumes and intraoperatively measured graft volumes correlated significantly. No significant differences between the presented automatic volumetry and the conventional volumetry were observed. A novel image processing technique was evaluated which allows a semi-automatic volume calculation and 3D visualisation of the different liver segments. (orig.)

  19. Applicability of 3D-CT facial reconstruction for forensic individual identification Aplicabilidade da reconstrução facial em 3D-TC para identificação individual forense

    Directory of Open Access Journals (Sweden)

    Sara dos Santos Rocha

    2003-03-01

    Full Text Available Computed tomography (CT is used in several clinical dentistry applications even by axial slices and two and three-dimensional reconstructed images (2D-CT and 3D-CT. The purpose of the current study is to assess the precision of linear measurements made in 3D-CT using craniometric patterns for individual identification in Forensic Dentistry. Five cadaver heads were submitted to a spiral computed tomography using axial slices, and 3D-CT reconstructions were obtained by volume rendering technique with computer graphics tools. Ten (10 craniometric measurements were determined in 3D-CT images by two examiners independently, twice each, and the standard error of intra- and inter-examiner measurements was assessed. The results demonstrated a low standard error of those measurements, from 0.85% to 3.09%. In conclusion, the linear measurements obtained in osseous and soft tissue structures were considered to be precise in 3D-CT with high imaging quality and resolution.A tomografia computadorizada (TC tem sido utilizada em diversas áreas clínicas da Odontologia; utilizam-se tanto seus cortes originais quanto as reconstruções em duas e três dimensões (2D-TC e 3D-TC. O presente estudo propõe avaliar a precisão das medidas lineares realizadas na 3D-TC, utilizando a craniometria, para fins de identificação individual na Odontologia Forense. Cinco cabeças de cadáveres foram submetidas a tomografia computadorizada em espiral por meio de cortes axiais e reconstruções em 3D-TC foram obtidas por meio da técnica de volume, utilizando recursos da computação gráfica. Medidas craniométricas (n = 10 foram determinadas nas imagens em 3D-TC por dois examinadores independentemente, duas vezes cada um, e uma análise de erro padrão percentual das medidas intra- e inter-examinadores foi realizada. Os resultados demonstraram um erro padrão percentual baixo apresentado por essas medidas, variando entre 0,85% e 3,09%. Em conclusão, as medidas lineares

  20. Robust extraction of the aorta and pulmonary artery from 3D MDCT image data

    Science.gov (United States)

    Taeprasartsit, Pinyo; Higgins, William E.

    2010-03-01

    Accurate definition of the aorta and pulmonary artery from three-dimensional (3D) multi-detector CT (MDCT) images is important for pulmonary applications. This work presents robust methods for defining the aorta and pulmonary artery in the central chest. The methods work on both contrast enhanced and no-contrast 3D MDCT image data. The automatic methods use a common approach employing model fitting and selection and adaptive refinement. During the occasional event that more precise vascular extraction is desired or the method fails, we also have an alternate semi-automatic fail-safe method. The semi-automatic method extracts the vasculature by extending the medial axes into a user-guided direction. A ground-truth study over a series of 40 human 3D MDCT images demonstrates the efficacy, accuracy, robustness, and efficiency of the methods.

  1. 2D-3D Registration of CT Vertebra Volume to Fluoroscopy Projection: A Calibration Model Assessment

    Directory of Open Access Journals (Sweden)

    Allen R

    2010-01-01

    Full Text Available This study extends a previous research concerning intervertebral motion registration by means of 2D dynamic fluoroscopy to obtain a more comprehensive 3D description of vertebral kinematics. The problem of estimating the 3D rigid pose of a CT volume of a vertebra from its 2D X-ray fluoroscopy projection is addressed. 2D-3D registration is obtained maximising a measure of similarity between Digitally Reconstructed Radiographs (obtained from the CT volume and real fluoroscopic projection. X-ray energy correction was performed. To assess the method a calibration model was realised a sheep dry vertebra was rigidly fixed to a frame of reference including metallic markers. Accurate measurement of 3D orientation was obtained via single-camera calibration of the markers and held as true 3D vertebra position; then, vertebra 3D pose was estimated and results compared. Error analysis revealed accuracy of the order of 0.1 degree for the rotation angles of about 1 mm for displacements parallel to the fluoroscopic plane, and of order of 10 mm for the orthogonal displacement.

  2. CT image of thymoma

    Energy Technology Data Exchange (ETDEWEB)

    Morioka, Nobuo; Shudo, Yuji; Jahana, Masanobu; Matsuki, Tsutomu; Kotani, Kazuhiko (Tottori Univ., Yonago (Japan). School of Medicine)

    1983-10-01

    Computor tomographic images of 11 patients who had had thymectomy for myasthenia gravis or thymoma were studied retrospectively. Of those 11 patients, malignant thymoma and benign condition including normal thymus were 6 and 5 respectively. On CT, calcification and lobulation with irregular margin seem to be reliable findings of malignancy. Defect or abscence of fatty plane and non-homogenous density are ancillary.

  3. 3D- VISUALIZATION BY RAYTRACING IMAGE SYNTHESIS ON GPU

    Directory of Open Access Journals (Sweden)

    Al-Oraiqat Anas M.

    2016-06-01

    Full Text Available This paper presents a realization of the approach to spatial 3D stereo of visualization of 3D images with use parallel Graphics processing unit (GPU. The experiments of realization of synthesis of images of a 3D stage by a method of trace of beams on GPU with Compute Unified Device Architecture (CUDA have shown that 60 % of the time is spent for the decision of a computing problem approximately, the major part of time (40 % is spent for transfer of data between the central processing unit and GPU for calculations and the organization process of visualization. The study of the influence of increase in the size of the GPU network at the speed of calculations showed importance of the correct task of structure of formation of the parallel computer network and general mechanism of parallelization.

  4. Statistical skull models from 3D X-ray images

    CERN Document Server

    Berar, M; Bailly, G; Payan, Y; Berar, Maxime; Desvignes, Michel; Payan, Yohan

    2006-01-01

    We present 2 statistical models of the skull and mandible built upon an elastic registration method of 3D meshes. The aim of this work is to relate degrees of freedom of skull anatomy, as static relations are of main interest for anthropology and legal medicine. Statistical models can effectively provide reconstructions together with statistical precision. In our applications, patient-specific meshes of the skull and the mandible are high-density meshes, extracted from 3D CT scans. All our patient-specific meshes are registrated in a subject-shared reference system using our 3D-to-3D elastic matching algorithm. Registration is based upon the minimization of a distance between the high density mesh and a shared low density mesh, defined on the vertexes, in a multi resolution approach. A Principal Component analysis is performed on the normalised registrated data to build a statistical linear model of the skull and mandible shape variation. The accuracy of the reconstruction is under the millimetre in the shape...

  5. Accurate positioning for head and neck cancer patients using 2D and 3D image guidance

    Science.gov (United States)

    Kang, Hyejoo; Lovelock, Dale M.; Yorke, Ellen D.; Kriminiski, Sergey; Lee, Nancy; Amols, Howard I.

    2011-01-01

    Our goal is to determine an optimized image-guided setup by comparing setup errors determined by two-dimensional (2D) and three-dimensional (3D) image guidance for head and neck cancer (HNC) patients immobilized by customized thermoplastic masks. Nine patients received weekly imaging sessions, for a total of 54, throughout treatment. Patients were first set up by matching lasers to surface marks (initial) and then translationally corrected using manual registration of orthogonal kilovoltage (kV) radiographs with DRRs (2D-2D) on bony anatomy. A kV cone beam CT (kVCBCT) was acquired and manually registered to the simulation CT using only translations (3D-3D) on the same bony anatomy to determine further translational corrections. After treatment, a second set of kVCBCT was acquired to assess intrafractional motion. Averaged over all sessions, 2D-2D registration led to translational corrections from initial setup of 3.5 ± 2.2 (range 0–8) mm. The addition of 3D-3D registration resulted in only small incremental adjustment (0.8 ± 1.5 mm). We retrospectively calculated patient setup rotation errors using an automatic rigid-body algorithm with 6 degrees of freedom (DoF) on regions of interest (ROI) of in-field bony anatomy (mainly the C2 vertebral body). Small rotations were determined for most of the imaging sessions; however, occasionally rotations > 3° were observed. The calculated intrafractional motion with automatic registration was < 3.5 mm for eight patients, and < 2° for all patients. We conclude that daily manual 2D-2D registration on radiographs reduces positioning errors for mask-immobilized HNC patients in most cases, and is easily implemented. 3D-3D registration adds little improvement over 2D-2D registration without correcting rotational errors. We also conclude that thermoplastic masks are effective for patient immobilization. PMID:21330971

  6. Low kV rotational 3D X-ray imaging for improved CNR of iodine contrast agent

    NARCIS (Netherlands)

    Schaefer, D.; Ahrens, M.; Grass, M.

    2011-01-01

    The contrast of iodine to soft tissue (water) decreases with higher tube voltage in reconstructed 3D X-ray images. Improved acquisition protocols with a tube voltage of about 80 kV for imaging iodine have been proposed earlier for diagnostic CT imaging. We investigate the contrast-to-noise ratio (CN

  7. Clinical Study of 3D Imaging and 3D Printing Technique for Patient-Specific Instrumentation in Total Knee Arthroplasty.

    Science.gov (United States)

    Qiu, Bing; Liu, Fei; Tang, Bensen; Deng, Biyong; Liu, Fang; Zhu, Weimin; Zhen, Dong; Xue, Mingyuan; Zhang, Mingjiao

    2017-01-25

    Patient-specific instrumentation (PSI) was designed to improve the accuracy of preoperative planning and postoperative prosthesis positioning in total knee arthroplasty (TKA). However, better understanding needs to be achieved due to the subtle nature of the PSI systems. In this study, 3D printing technique based on the image data of computed tomography (CT) has been utilized for optimal controlling of the surgical parameters. Two groups of TKA cases have been randomly selected as PSI group and control group with no significant difference of age and sex (p > 0.05). The PSI group is treated with 3D printed cutting guides whereas the control group is treated with conventional instrumentation (CI). By evaluating the proximal osteotomy amount, distal osteotomy amount, valgus angle, external rotation angle, and tibial posterior slope angle of patients, it can be found that the preoperative quantitative assessment and intraoperative changes can be controlled with PSI whereas CI is relied on experience. In terms of postoperative parameters, such as hip-knee-ankle (HKA), frontal femoral component (FFC), frontal tibial component (FTC), and lateral tibial component (LTC) angles, there is a significant improvement in achieving the desired implant position (p implantation compared against control method, which indicates potential for optimal HKA, FFC, and FTC angles.

  8. Autonomous Planetary 3-D Reconstruction From Satellite Images

    DEFF Research Database (Denmark)

    Denver, Troelz

    1999-01-01

    is discussed.Based on such features, 3-D representations may be compiled from two or more 2-D satellite images. The main purposes of such a mapping system are extraction of landing sites, objects of scientific interest and general planetary surveying. All data processing is performed autonomously onboard...

  9. Integration of real-time 3D image acquisition and multiview 3D display

    Science.gov (United States)

    Zhang, Zhaoxing; Geng, Zheng; Li, Tuotuo; Li, Wei; Wang, Jingyi; Liu, Yongchun

    2014-03-01

    Seamless integration of 3D acquisition and 3D display systems offers enhanced experience in 3D visualization of the real world objects or scenes. The vivid representation of captured 3D objects displayed on a glasses-free 3D display screen could bring the realistic viewing experience to viewers as if they are viewing real-world scene. Although the technologies in 3D acquisition and 3D display have advanced rapidly in recent years, effort is lacking in studying the seamless integration of these two different aspects of 3D technologies. In this paper, we describe our recent progress on integrating a light-field 3D acquisition system and an autostereoscopic multiview 3D display for real-time light field capture and display. This paper focuses on both the architecture design and the implementation of the hardware and the software of this integrated 3D system. A prototype of the integrated 3D system is built to demonstrate the real-time 3D acquisition and 3D display capability of our proposed system.

  10. Analysis of 3D Prints by X-ray Computed Microtomography and Terahertz Pulsed Imaging

    DEFF Research Database (Denmark)

    Markl, Daniel; Zeitler, J Axel; Rasch, Cecilie

    2016-01-01

    PURPOSE: A 3D printer was used to realise compartmental dosage forms containing multiple active pharmaceutical ingredient (API) formulations. This work demonstrates the microstructural characterisation of 3D printed solid dosage forms using X-ray computed microtomography (XμCT) and terahertz pulsed...... imaging (TPI). METHODS: Printing was performed with either polyvinyl alcohol (PVA) or polylactic acid (PLA). The structures were examined by XμCT and TPI. Liquid self-nanoemulsifying drug delivery system (SNEDDS) formulations containing saquinavir and halofantrine were incorporated into the 3D printed...... was characterised by XμCT and TPI on the basis of the computer-aided design (CAD) models of the dosage form (compartmentalised PVA structures were 7.5 ± 0.75% larger than designed; n = 3). CONCLUSIONS: The 3D printer can reproduce specific structures very accurately, whereas the 3D prints can deviate from...

  11. Extracting 3D Layout From a Single Image Using Global Image Structures

    NARCIS (Netherlands)

    Lou, Z.; Gevers, T.; Hu, N.

    2015-01-01

    Extracting the pixel-level 3D layout from a single image is important for different applications, such as object localization, image, and video categorization. Traditionally, the 3D layout is derived by solving a pixel-level classification problem. However, the image-level 3D structure can be very b

  12. Projective 3D-reconstruction of Uncalibrated Endoscopic Images

    Directory of Open Access Journals (Sweden)

    P. Faltin

    2010-01-01

    Full Text Available The most common medical diagnostic method for urinary bladder cancer is cystoscopy. This inspection of the bladder is performed by a rigid endoscope, which is usually guided close to the bladder wall. This causes a very limited field of view; difficulty of navigation is aggravated by the usage of angled endoscopes. These factors cause difficulties in orientation and visual control. To overcome this problem, the paper presents a method for extracting 3D information from uncalibrated endoscopic image sequences and for reconstructing the scene content. The method uses the SURF-algorithm to extract features from the images and relates the images by advanced matching. To stabilize the matching, the epipolar geometry is extracted for each image pair using a modified RANSAC-algorithm. Afterwards these matched point pairs are used to generate point triplets over three images and to describe the trifocal geometry. The 3D scene points are determined by applying triangulation to the matched image points. Thus, these points are used to generate a projective 3D reconstruction of the scene, and provide the first step for further metric reconstructions.

  13. Factors Affecting Dimensional Accuracy of 3-D Printed Anatomical Structures Derived from CT Data.

    Science.gov (United States)

    Ogden, Kent M; Aslan, Can; Ordway, Nathaniel; Diallo, Dalanda; Tillapaugh-Fay, Gwen; Soman, Pranav

    2015-12-01

    Additive manufacturing and bio-printing, with the potential for direct fabrication of complex patient-specific anatomies derived from medical scan data, are having an ever-increasing impact on the practice of medicine. Anatomic structures are typically derived from CT or MRI scans, and there are multiple steps in the model derivation process that influence the geometric accuracy of the printed constructs. In this work, we compare the dimensional accuracy of 3-D printed constructs of an L1 vertebra derived from CT data for an ex vivo cadaver T-L spine with the original vertebra. Processing of segmented structures using binary median filters and various surface extraction algorithms is evaluated for the effect on model dimensions. We investigate the effects of changing CT reconstruction kernels by scanning simple geometric objects and measuring the impact on the derived model dimensions. We also investigate if there are significant differences between physical and virtual model measurements. The 3-D models were printed using a commercial 3-D printer, the Replicator 2 (MakerBot, Brooklyn, NY) using polylactic acid (PLA) filament. We found that changing parameters during the scan reconstruction, segmentation, filtering, and surface extraction steps will have an effect on the dimensions of the final model. These effects need to be quantified for specific situations that rely on the accuracy of 3-D printed models used in medicine or tissue engineering applications.

  14. Deformable Surface 3D Reconstruction from Monocular Images

    CERN Document Server

    Salzmann, Matthieu

    2010-01-01

    Being able to recover the shape of 3D deformable surfaces from a single video stream would make it possible to field reconstruction systems that run on widely available hardware without requiring specialized devices. However, because many different 3D shapes can have virtually the same projection, such monocular shape recovery is inherently ambiguous. In this survey, we will review the two main classes of techniques that have proved most effective so far: The template-based methods that rely on establishing correspondences with a reference image in which the shape is already known, and non-rig

  15. Combining 2D wavelet edge highlighting and 3D thresholding for lung segmentation in thin-slice CT.

    Science.gov (United States)

    Korfiatis, P; Skiadopoulos, S; Sakellaropoulos, P; Kalogeropoulou, C; Costaridou, L

    2007-12-01

    The first step in lung analysis by CT is the identification of the lung border. To deal with the increased number of sections per scan in thin-slice multidetector CT, it has been crucial to develop accurate and automated lung segmentation algorithms. In this study, an automated method for lung segmentation of thin-slice CT data is presented. The method exploits the advantages of a two-dimensional wavelet edge-highlighting step in lung border delineation. Lung volume segmentation is achieved with three-dimensional (3D) grey level thresholding, using a minimum error technique. 3D thresholding, combined with the wavelet pre-processing step, successfully deals with lung border segmentation challenges, such as anterior or posterior junction lines and juxtapleural nodules. Finally, to deal with mediastinum border under-segmentation, 3D morphological closing with a spherical structural element is applied. The performance of the proposed method is quantitatively assessed on a dataset originating from the Lung Imaging Database Consortium (LIDC) by comparing automatically derived borders with the manually traced ones. Segmentation performance, averaged over left and right lung volumes, for lung volume overlap is 0.983+/-0.008, whereas for shape differentiation in terms of mean distance it is 0.770+/-0.251 mm (root mean square distance is 0.520+/-0.008 mm; maximum distance is 3.327+/-1.637 mm). The effect of the wavelet pre-processing step was assessed by comparing the proposed method with the 3D thresholding technique (applied on original volume data). This yielded statistically significant differences for all segmentation metrics (p<0.01). Results demonstrate an accurate method that could be used as a first step in computer lung analysis by CT.

  16. Renal Tumor Cryoablation Planning. The Efficiency of Simulation on Reconstructed 3D CT Scan

    Directory of Open Access Journals (Sweden)

    Ciprian Valerian LUCAN

    2010-12-01

    Full Text Available Introduction & Objective: Nephron-sparing surgical techniques risks are related to tumor relationships with adjacent anatomic structures. Complexity of the renal anatomy drives the interest to develop tools for 3D reconstruction and surgery simulation. The aim of the article was to assess the simulation on reconstructed 3D CT scan used for planning the cryoablation. Material & Method: A prospective randomized study was performed between Jan. 2007 and July 2009 on 27 patients who underwent retroperitoneoscopic T1a renal tumors cryoablation (RC. All patients were assessed preoperatively by CT scan, also used for 3D volume rendering. In the Gr.A, the patients underwent surgery planning by simulation on 3D CT scan. In the Gr.B., patients underwent standard RC. The two groups were compared in terms of surgical time, bleeding, postoperative drainage, analgesics requirement, hospital stay, time to socio-professional reintegration. Results: Fourteen patients underwent preoperative cryoablation planning (Gr.A and 13 patients underwent standard CR (Gr.B. All parameters analyzed were shorter in the Gr.A. On multivariate logistic regression, only shortens of the surgical time (138.79±5.51 min. in Gr.A. vs. 140.92±5.54 min in Gr.B. and bleeding (164.29±60.22 mL in Gr.A. vs. 215.38±100.80 mL in Gr.B. achieved statistical significance (p<0.05. The number of cryoneedles assessed by simulation had a 92.52% accuracy when compared with those effectively used. Conclusions: Simulation of the cryoablation using reconstructed 3D CT scan improves the surgical results. The application used for simulation was able to accurately assess the number of cryoneedles required for tumor ablation, their direction and approach.

  17. TU-CD-BRA-01: A Novel 3D Registration Method for Multiparametric Radiological Images

    Energy Technology Data Exchange (ETDEWEB)

    Akhbardeh, A [The Russell H. Morgan Department of Radiology and Radiological Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD (United States); Parekth, VS [Department of Computer Science, The Johns Hopkins University, Baltimore, MD (United States); Jacobs, MA [The Russell H. Morgan Department of Radiology and Radiological Sciences and Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Sparks, MD (United States)

    2015-06-15

    Purpose: Multiparametric and multimodality radiological imaging methods, such as, magnetic resonance imaging(MRI), computed tomography(CT), and positron emission tomography(PET), provide multiple types of tissue contrast and anatomical information for clinical diagnosis. However, these radiological modalities are acquired using very different technical parameters, e.g.,field of view(FOV), matrix size, and scan planes, which, can lead to challenges in registering the different data sets. Therefore, we developed a hybrid registration method based on 3D wavelet transformation and 3D interpolations that performs 3D resampling and rotation of the target radiological images without loss of information Methods: T1-weighted, T2-weighted, diffusion-weighted-imaging(DWI), dynamic-contrast-enhanced(DCE) MRI and PET/CT were used in the registration algorithm from breast and prostate data at 3T MRI and multimodality(PET/CT) cases. The hybrid registration scheme consists of several steps to reslice and match each modality using a combination of 3D wavelets, interpolations, and affine registration steps. First, orthogonal reslicing is performed to equalize FOV, matrix sizes and the number of slices using wavelet transformation. Second, angular resampling of the target data is performed to match the reference data. Finally, using optimized angles from resampling, 3D registration is performed using similarity transformation(scaling and translation) between the reference and resliced target volume is performed. After registration, the mean-square-error(MSE) and Dice Similarity(DS) between the reference and registered target volumes were calculated. Results: The 3D registration method registered synthetic and clinical data with significant improvement(p<0.05) of overlap between anatomical structures. After transforming and deforming the synthetic data, the MSE and Dice similarity were 0.12 and 0.99. The average improvement of the MSE in breast was 62%(0.27 to 0.10) and prostate was

  18. 3D Medical Image Interpolation Based on Parametric Cubic Convolution

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In the process of display, manipulation and analysis of biomedical image data, they usually need to be converted to data of isotropic discretization through the process of interpolation, while the cubic convolution interpolation is widely used due to its good tradeoff between computational cost and accuracy. In this paper, we present a whole concept for the 3D medical image interpolation based on cubic convolution, and the six methods, with the different sharp control parameter, which are formulated in details. Furthermore, we also give an objective comparison for these methods using data sets with the different slice spacing. Each slice in these data sets is estimated by each interpolation method and compared with the original slice using three measures: mean-squared difference, number of sites of disagreement, and largest difference. According to the experimental results, we present a recommendation for 3D medical images under the different situations in the end.

  19. A review of automated image understanding within 3D baggage computed tomography security screening.

    Science.gov (United States)

    Mouton, Andre; Breckon, Toby P

    2015-01-01

    Baggage inspection is the principal safeguard against the transportation of prohibited and potentially dangerous materials at airport security checkpoints. Although traditionally performed by 2D X-ray based scanning, increasingly stringent security regulations have led to a growing demand for more advanced imaging technologies. The role of X-ray Computed Tomography is thus rapidly expanding beyond the traditional materials-based detection of explosives. The development of computer vision and image processing techniques for the automated understanding of 3D baggage-CT imagery is however, complicated by poor image resolutions, image clutter and high levels of noise and artefacts. We discuss the recent and most pertinent advancements and identify topics for future research within the challenging domain of automated image understanding for baggage security screening CT.

  20. Vhrs Stereo Images for 3d Modelling of Buildings

    Science.gov (United States)

    Bujakiewicz, A.; Holc, M.

    2012-07-01

    The paper presents the project which was carried out in the Photogrammetric Laboratory of Warsaw University of Technology. The experiment is concerned with the extraction of 3D vector data for buildings creation from 3D photogrammetric model based on the Ikonos stereo images. The model was reconstructed with photogrammetric workstation - Summit Evolution combined with ArcGIS 3D platform. Accuracy of 3D model was significantly improved by use for orientation of pair of satellite images the stereo measured tie points distributed uniformly around the model area in addition to 5 control points. The RMS for model reconstructed on base of the RPC coefficients only were 16,6 m, 2,7 m and 47,4 m, for X, Y and Z coordinates, respectively. By addition of 5 control points the RMS were improved to 0,7 m, 0,7 m 1,0 m, where the best results were achieved when RMS were estimated from deviations in 17 check points (with 5 control points)and amounted to 0,4 m, 0,5 m and 0,6 m, for X, Y, and Z respectively. The extracted 3D vector data for buildings were integrated with 2D data of the ground footprints and afterwards they were used for 3D modelling of buildings in Google SketchUp software. The final results were compared with the reference data obtained from other sources. It was found that the shape of buildings (in concern to the number of details) had been reconstructed on level of LoD1, when the accuracy of these models corresponded to the level of LoD2.

  1. VHRS STEREO IMAGES FOR 3D MODELLING OF BUILDINGS

    Directory of Open Access Journals (Sweden)

    A. Bujakiewicz

    2012-07-01

    Full Text Available The paper presents the project which was carried out in the Photogrammetric Laboratory of Warsaw University of Technology. The experiment is concerned with the extraction of 3D vector data for buildings creation from 3D photogrammetric model based on the Ikonos stereo images. The model was reconstructed with photogrammetric workstation – Summit Evolution combined with ArcGIS 3D platform. Accuracy of 3D model was significantly improved by use for orientation of pair of satellite images the stereo measured tie points distributed uniformly around the model area in addition to 5 control points. The RMS for model reconstructed on base of the RPC coefficients only were 16,6 m, 2,7 m and 47,4 m, for X, Y and Z coordinates, respectively. By addition of 5 control points the RMS were improved to 0,7 m, 0,7 m 1,0 m, where the best results were achieved when RMS were estimated from deviations in 17 check points (with 5 control pointsand amounted to 0,4 m, 0,5 m and 0,6 m, for X, Y, and Z respectively. The extracted 3D vector data for buildings were integrated with 2D data of the ground footprints and afterwards they were used for 3D modelling of buildings in Google SketchUp software. The final results were compared with the reference data obtained from other sources. It was found that the shape of buildings (in concern to the number of details had been reconstructed on level of LoD1, when the accuracy of these models corresponded to the level of LoD2.

  2. 3D Reconstruction of Human Motion from Monocular Image Sequences.

    Science.gov (United States)

    Wandt, Bastian; Ackermann, Hanno; Rosenhahn, Bodo

    2016-08-01

    This article tackles the problem of estimating non-rigid human 3D shape and motion from image sequences taken by uncalibrated cameras. Similar to other state-of-the-art solutions we factorize 2D observations in camera parameters, base poses and mixing coefficients. Existing methods require sufficient camera motion during the sequence to achieve a correct 3D reconstruction. To obtain convincing 3D reconstructions from arbitrary camera motion, our method is based on a-priorly trained base poses. We show that strong periodic assumptions on the coefficients can be used to define an efficient and accurate algorithm for estimating periodic motion such as walking patterns. For the extension to non-periodic motion we propose a novel regularization term based on temporal bone length constancy. In contrast to other works, the proposed method does not use a predefined skeleton or anthropometric constraints and can handle arbitrary camera motion. We achieve convincing 3D reconstructions, even under the influence of noise and occlusions. Multiple experiments based on a 3D error metric demonstrate the stability of the proposed method. Compared to other state-of-the-art methods our algorithm shows a significant improvement.

  3. Interactive 2D to 3D stereoscopic image synthesis

    Science.gov (United States)

    Feldman, Mark H.; Lipton, Lenny

    2005-03-01

    Advances in stereoscopic display technologies, graphic card devices, and digital imaging algorithms have opened up new possibilities in synthesizing stereoscopic images. The power of today"s DirectX/OpenGL optimized graphics cards together with adapting new and creative imaging tools found in software products such as Adobe Photoshop, provide a powerful environment for converting planar drawings and photographs into stereoscopic images. The basis for such a creative process is the focus of this paper. This article presents a novel technique, which uses advanced imaging features and custom Windows-based software that utilizes the Direct X 9 API to provide the user with an interactive stereo image synthesizer. By creating an accurate and interactive world scene with moveable and flexible depth map altered textured surfaces, perspective stereoscopic cameras with both visible frustums and zero parallax planes, a user can precisely model a virtual three-dimensional representation of a real-world scene. Current versions of Adobe Photoshop provide a creative user with a rich assortment of tools needed to highlight elements of a 2D image, simulate hidden areas, and creatively shape them for a 3D scene representation. The technique described has been implemented as a Photoshop plug-in and thus allows for a seamless transition of these 2D image elements into 3D surfaces, which are subsequently rendered to create stereoscopic views.

  4. Large distance 3D imaging of hidden objects

    Science.gov (United States)

    Rozban, Daniel; Aharon Akram, Avihai; Kopeika, N. S.; Abramovich, A.; Levanon, Assaf

    2014-06-01

    Imaging systems in millimeter waves are required for applications in medicine, communications, homeland security, and space technology. This is because there is no known ionization hazard for biological tissue, and atmospheric attenuation in this range of the spectrum is low compared to that of infrared and optical rays. The lack of an inexpensive room temperature detector makes it difficult to give a suitable real time implement for the above applications. A 3D MMW imaging system based on chirp radar was studied previously using a scanning imaging system of a single detector. The system presented here proposes to employ a chirp radar method with Glow Discharge Detector (GDD) Focal Plane Array (FPA of plasma based detectors) using heterodyne detection. The intensity at each pixel in the GDD FPA yields the usual 2D image. The value of the I-F frequency yields the range information at each pixel. This will enable 3D MMW imaging. In this work we experimentally demonstrate the feasibility of implementing an imaging system based on radar principles and FPA of inexpensive detectors. This imaging system is shown to be capable of imaging objects from distances of at least 10 meters.

  5. Evaluation of Kinect 3D Sensor for Healthcare Imaging.

    Science.gov (United States)

    Pöhlmann, Stefanie T L; Harkness, Elaine F; Taylor, Christopher J; Astley, Susan M

    2016-01-01

    Microsoft Kinect is a three-dimensional (3D) sensor originally designed for gaming that has received growing interest as a cost-effective and safe device for healthcare imaging. Recent applications of Kinect in health monitoring, screening, rehabilitation, assistance systems, and intervention support are reviewed here. The suitability of available technologies for healthcare imaging applications is assessed. The performance of Kinect I, based on structured light technology, is compared with that of the more recent Kinect II, which uses time-of-flight measurement, under conditions relevant to healthcare applications. The accuracy, precision, and resolution of 3D images generated with Kinect I and Kinect II are evaluated using flat cardboard models representing different skin colors (pale, medium, and dark) at distances ranging from 0.5 to 1.2 m and measurement angles of up to 75°. Both sensors demonstrated high accuracy (majority of measurements Kinect I is capable of imaging at shorter measurement distances, but Kinect II enables structures angled at over 60° to be evaluated. Kinect II showed significantly higher precision and Kinect I showed significantly higher resolution (both p Kinect is not a medical imaging device, both sensor generations show performance adequate for a range of healthcare imaging applications. Kinect I is more appropriate for short-range imaging and Kinect II is more appropriate for imaging highly curved surfaces such as the face or breast.

  6. 3D Image Reconstruction from Compton camera data

    CERN Document Server

    Kuchment, Peter

    2016-01-01

    In this paper, we address analytically and numerically the inversion of the integral transform (\\emph{cone} or \\emph{Compton} transform) that maps a function on $\\mathbb{R}^3$ to its integrals over conical surfaces. It arises in a variety of imaging techniques, e.g. in astronomy, optical imaging, and homeland security imaging, especially when the so called Compton cameras are involved. Several inversion formulas are developed and implemented numerically in $3D$ (the much simpler $2D$ case was considered in a previous publication).

  7. Combined registration of 3D tibia and femur implant models in 3D magnetic resonance images

    Science.gov (United States)

    Englmeier, Karl-Hans; Siebert, Markus; von Eisenhart-Rothe, Ruediger; Graichen, Heiko

    2008-03-01

    The most frequent reasons for revision of total knee arthroplasty are loosening and abnormal axial alignment leading to an unphysiological kinematic of the knee implant. To get an idea about the postoperative kinematic of the implant, it is essential to determine the position and orientation of the tibial and femoral prosthesis. Therefore we developed a registration method for fitting 3D CAD-models of knee joint prostheses into an 3D MR image. This rigid registration is the basis for a quantitative analysis of the kinematics of knee implants. Firstly the surface data of the prostheses models are converted into a voxel representation; a recursive algorithm determines all boundary voxels of the original triangular surface data. Secondly an initial preconfiguration of the implants by the user is still necessary for the following step: The user has to perform a rough preconfiguration of both remaining prostheses models, so that the fine matching process gets a reasonable starting point. After that an automated gradient-based fine matching process determines the best absolute position and orientation: This iterative process changes all 6 parameters (3 rotational- and 3 translational parameters) of a model by a minimal amount until a maximum value of the matching function is reached. To examine the spread of the final solutions of the registration, the interobserver variability was measured in a group of testers. This variability, calculated by the relative standard deviation, improved from about 50% (pure manual registration) to 0.5% (rough manual preconfiguration and subsequent fine registration with the automatic fine matching process).

  8. Traversing and labeling interconnected vascular tree structures from 3D medical images

    Science.gov (United States)

    O'Dell, Walter G.; Govindarajan, Sindhuja Tirumalai; Salgia, Ankit; Hegde, Satyanarayan; Prabhakaran, Sreekala; Finol, Ender A.; White, R. James

    2014-03-01

    Purpose: Detailed characterization of pulmonary vascular anatomy has important applications for the diagnosis and management of a variety of vascular diseases. Prior efforts have emphasized using vessel segmentation to gather information on the number or branches, number of bifurcations, and branch length and volume, but accurate traversal of the vessel tree to identify and repair erroneous interconnections between adjacent branches and neighboring tree structures has not been carefully considered. In this study, we endeavor to develop and implement a successful approach to distinguishing and characterizing individual vascular trees from among a complex intermingling of trees. Methods: We developed strategies and parameters in which the algorithm identifies and repairs false branch inter-tree and intra-tree connections to traverse complicated vessel trees. A series of two-dimensional (2D) virtual datasets with a variety of interconnections were constructed for development, testing, and validation. To demonstrate the approach, a series of real 3D computed tomography (CT) lung datasets were obtained, including that of an anthropomorphic chest phantom; an adult human chest CT; a pediatric patient chest CT; and a micro-CT of an excised rat lung preparation. Results: Our method was correct in all 2D virtual test datasets. For each real 3D CT dataset, the resulting simulated vessel tree structures faithfully depicted the vessel tree structures that were originally extracted from the corresponding lung CT scans. Conclusion: We have developed a comprehensive strategy for traversing and labeling interconnected vascular trees and successfully implemented its application to pulmonary vessels observed using 3D CT images of the chest.

  9. Combining Different Modalities for 3D Imaging of Biological Objects

    CERN Document Server

    Tsyganov, E; Kulkarni, P; Mason, R; Parkey, R; Seliuonine, S; Shay, J; Soesbe, T; Zhezher, V; Zinchenko, A I

    2005-01-01

    A resolution enhanced NaI(Tl)-scintillator micro-SPECT device using pinhole collimator geometry has been built and tested with small animals. This device was constructed based on a depth-of-interaction measurement using a thick scintillator crystal and a position sensitive PMT to measure depth-dependent scintillator light profiles. Such a measurement eliminates the parallax error that degrades the high spatial resolution required for small animal imaging. This novel technique for 3D gamma-ray detection was incorporated into the micro-SPECT device and tested with a $^{57}$Co source and $^{98m}$Tc-MDP injected in mice body. To further enhance the investigating power of the tomographic imaging different imaging modalities can be combined. In particular, as proposed and shown in this paper, the optical imaging permits a 3D reconstruction of the animal's skin surface thus improving visualization and making possible depth-dependent corrections, necessary for bioluminescence 3D reconstruction in biological objects. ...

  10. Image Appraisal for 2D and 3D Electromagnetic Inversion

    Energy Technology Data Exchange (ETDEWEB)

    Alumbaugh, D.L.; Newman, G.A.

    1999-01-28

    Linearized methods are presented for appraising image resolution and parameter accuracy in images generated with two and three dimensional non-linear electromagnetic inversion schemes. When direct matrix inversion is employed, the model resolution and posterior model covariance matrices can be directly calculated. A method to examine how the horizontal and vertical resolution varies spatially within the electromagnetic property image is developed by examining the columns of the model resolution matrix. Plotting the square root of the diagonal of the model covariance matrix yields an estimate of how errors in the inversion process such as data noise and incorrect a priori assumptions about the imaged model map into parameter error. This type of image is shown to be useful in analyzing spatial variations in the image sensitivity to the data. A method is analyzed for statistically estimating the model covariance matrix when the conjugate gradient method is employed rather than a direct inversion technique (for example in 3D inversion). A method for calculating individual columns of the model resolution matrix using the conjugate gradient method is also developed. Examples of the image analysis techniques are provided on 2D and 3D synthetic cross well EM data sets, as well as a field data set collected at the Lost Hills Oil Field in Central California.

  11. Measurement of facial soft tissues thickness using 3D computed tomographic images

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ho Gul; Kim, Kee Deog; Shin, Dong Won; Hu, Kyung Seok; Lee, Jae Bum; Park, Hyok; Park, Chang Seo [Yonsei Univ. Hospital, Seoul (Korea, Republic of); Han, Seung Ho [Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2006-03-15

    To evaluate accuracy and reliability of program to measure facial soft tissue thickness using 3D computed tomographic images by comparing with direct measurement. One cadaver was scanned with a Helical CT with 3 mm slice thickness and 3 mm/sec table speed. The acquired data was reconstructed with 1.5 mm reconstruction interval and the images were transferred to a personal computer. The facial soft tissue thickness were measured using a program developed newly in 3D image. For direct measurement, the cadaver was cut with a bone cutter and then a ruler was placed above the cut side. The procedure was followed by taking pictures of the facial soft tissues with a high-resolution digital camera. Then the measurements were done in the photographic images and repeated for ten times. A repeated measure analysis of variance was adopted to compare and analyze the measurements resulting from the two different methods. Comparison according to the areas was analyzed by Mann-Whitney test. There were no statistically significant differences between the direct measurements and those using the 3D images(p>0.05). There were statistical differences in the measurements on 17 points but all the points except 2 points showed a mean difference of 0.5 mm or less. The developed software program to measure the facial soft tissue thickness using 3D images was so accurate that it allows to measure facial soft tissue thickness more easily in forensic science and anthropology.

  12. Optimal Point Spread Function Design for 3D Imaging

    Science.gov (United States)

    Shechtman, Yoav; Sahl, Steffen J.; Backer, Adam S.; Moerner, W. E.

    2015-01-01

    To extract from an image of a single nanoscale object maximum physical information about its position, we propose and demonstrate a framework for pupil-plane modulation for 3D imaging applications requiring precise localization, including single-particle tracking and super-resolution microscopy. The method is based on maximizing the information content of the system, by formulating and solving the appropriate optimization problem – finding the pupil-plane phase pattern that would yield a PSF with optimal Fisher information properties. We use our method to generate and experimentally demonstrate two example PSFs: one optimized for 3D localization precision over a 3 μm depth of field, and another with an unprecedented 5 μm depth of field, both designed to perform under physically common conditions of high background signals. PMID:25302889

  13. 3D reconstruction of concave surfaces using polarisation imaging

    Science.gov (United States)

    Sohaib, A.; Farooq, A. R.; Ahmed, J.; Smith, L. N.; Smith, M. L.

    2015-06-01

    This paper presents a novel algorithm for improved shape recovery using polarisation-based photometric stereo. The majority of previous research using photometric stereo involves 3D reconstruction using both the diffuse and specular components of light; however, this paper suggests the use of the specular component only as it is the only form of light that comes directly off the surface without subsurface scattering or interreflections. Experiments were carried out on both real and synthetic surfaces. Real images were obtained using a polarisation-based photometric stereo device while synthetic images were generated using PovRay® software. The results clearly demonstrate that the proposed method can extract three-dimensional (3D) surface information effectively even for concave surfaces with complex texture and surface reflectance.

  14. 3D RECONSTRUCTION FROM MULTI-VIEW MEDICAL X-RAY IMAGES – REVIEW AND EVALUATION OF EXISTING METHODS

    Directory of Open Access Journals (Sweden)

    S. Hosseinian

    2015-12-01

    Full Text Available The 3D concept is extremely important in clinical studies of human body. Accurate 3D models of bony structures are currently required in clinical routine for diagnosis, patient follow-up, surgical planning, computer assisted surgery and biomechanical applications. However, 3D conventional medical imaging techniques such as computed tomography (CT scan and magnetic resonance imaging (MRI have serious limitations such as using in non-weight-bearing positions, costs and high radiation dose(for CT. Therefore, 3D reconstruction methods from biplanar X-ray images have been taken into consideration as reliable alternative methods in order to achieve accurate 3D models with low dose radiation in weight-bearing positions. Different methods have been offered for 3D reconstruction from X-ray images using photogrammetry which should be assessed. In this paper, after demonstrating the principles of 3D reconstruction from X-ray images, different existing methods of 3D reconstruction of bony structures from radiographs are classified and evaluated with various metrics and their advantages and disadvantages are mentioned. Finally, a comparison has been done on the presented methods with respect to several metrics such as accuracy, reconstruction time and their applications. With regards to the research, each method has several advantages and disadvantages which should be considered for a specific application.

  15. 3D scene reconstruction based on 3D laser point cloud combining UAV images

    Science.gov (United States)

    Liu, Huiyun; Yan, Yangyang; Zhang, Xitong; Wu, Zhenzhen

    2016-03-01

    It is a big challenge capturing and modeling 3D information of the built environment. A number of techniques and technologies are now in use. These include GPS, and photogrammetric application and also remote sensing applications. The experiment uses multi-source data fusion technology for 3D scene reconstruction based on the principle of 3D laser scanning technology, which uses the laser point cloud data as the basis and Digital Ortho-photo Map as an auxiliary, uses 3DsMAX software as a basic tool for building three-dimensional scene reconstruction. The article includes data acquisition, data preprocessing, 3D scene construction. The results show that the 3D scene has better truthfulness, and the accuracy of the scene meet the need of 3D scene construction.

  16. Utilization of multiple frequencies in 3D nonlinear microwave imaging

    DEFF Research Database (Denmark)

    Jensen, Peter Damsgaard; Rubæk, Tonny; Mohr, Johan Jacob

    2012-01-01

    The use of multiple frequencies in a nonlinear microwave algorithm is considered. Using multiple frequencies allows for obtaining the improved resolution available at the higher frequencies while retaining the regularizing effects of the lower frequencies. However, a number of different challenges...... at lower frequencies are used as starting guesses for reconstructions at higher frequencies. The performance is illustrated using simulated 2-D data and data obtained with the 3-D DTU microwave imaging system....

  17. Applying microCT and 3D Visualization to Jurassic Silicified Conifer Seed Cones: A Virtual Advantage Over Thin-Sectioning

    Directory of Open Access Journals (Sweden)

    Carole T. Gee

    2013-11-01

    Full Text Available Premise of the study: As an alternative to conventional thin-sectioning, which destroys fossil material, high-resolution X-ray computed tomography (also called microtomography or microCT integrated with scientific visualization, three-dimensional (3D image segmentation, size analysis, and computer animation is explored as a nondestructive method of imaging the internal anatomy of 150-million-year-old conifer seed cones from the Late Jurassic Morrison Formation, USA, and of recent and other fossil cones. Methods: MicroCT was carried out on cones using a General Electric phoenix v|tome|x s 240D, and resulting projections were processed with visualization software to produce image stacks of serial single sections for two-dimensional (2D visualization, 3D segmented reconstructions with targeted structures in color, and computer animations. Results: If preserved in differing densities, microCT produced images of internal fossil tissues that showed important characters such as seed phyllotaxy or number of seeds per cone scale. Color segmentation of deeply embedded seeds highlighted the arrangement of seeds in spirals. MicroCT of recent cones was even more effective. Conclusions: This is the first paper on microCT integrated with 3D segmentation and computer animation applied to silicified seed cones, which resulted in excellent 2D serial sections and segmented 3D reconstructions, revealing features requisite to cone identification and understanding of strobilus construction.

  18. Joint calibration of 3D resist image and CDSEM

    Science.gov (United States)

    Chou, C. S.; He, Y. Y.; Tang, Y. P.; Chang, Y. T.; Huang, W. C.; Liu, R. G.; Gau, T. S.

    2013-04-01

    Traditionally, an optical proximity correction model is to evaluate the resist image at a specific depth within the photoresist and then extract the resist contours from the image. Calibration is generally implemented by comparing resist contours with the critical dimensions (CD). The wafer CD is usually collected by a scanning electron microscope (SEM), which evaluates the CD based on some criterion that is a function of gray level, differential signal, threshold or other parameters set by the SEM. However, the criterion does not reveal which depth the CD is obtained at. This depth inconsistency between modeling and SEM makes the model calibration difficult for low k1 images. In this paper, the vertical resist profile is obtained by modifying the model from planar (2D) to quasi-3D approach and comparing the CD from this new model with SEM CD. For this quasi-3D model, the photoresist diffusion along the depth of the resist is considered and the 3D photoresist contours are evaluated. The performance of this new model is studied and is better than the 2D model.

  19. Discrete Method of Images for 3D Radio Propagation Modeling

    Science.gov (United States)

    Novak, Roman

    2016-09-01

    Discretization by rasterization is introduced into the method of images (MI) in the context of 3D deterministic radio propagation modeling as a way to exploit spatial coherence of electromagnetic propagation for fine-grained parallelism. Traditional algebraic treatment of bounding regions and surfaces is replaced by computer graphics rendering of 3D reflections and double refractions while building the image tree. The visibility of reception points and surfaces is also resolved by shader programs. The proposed rasterization is shown to be of comparable run time to that of the fundamentally parallel shooting and bouncing rays. The rasterization does not affect the signal evaluation backtracking step, thus preserving its advantage over the brute force ray-tracing methods in terms of accuracy. Moreover, the rendering resolution may be scaled back for a given level of scenario detail with only marginal impact on the image tree size. This allows selection of scene optimized execution parameters for faster execution, giving the method a competitive edge. The proposed variant of MI can be run on any GPU that supports real-time 3D graphics.

  20. 3D reconstruction of multiple stained histology images

    Directory of Open Access Journals (Sweden)

    Yi Song

    2013-01-01

    Full Text Available Context: Three dimensional (3D tissue reconstructions from the histology images with different stains allows the spatial alignment of structural and functional elements highlighted by different stains for quantitative study of many physiological and pathological phenomena. This has significant potential to improve the understanding of the growth patterns and the spatial arrangement of diseased cells, and enhance the study of biomechanical behavior of the tissue structures towards better treatments (e.g. tissue-engineering applications. Methods: This paper evaluates three strategies for 3D reconstruction from sets of two dimensional (2D histological sections with different stains, by combining methods of 2D multi-stain registration and 3D volumetric reconstruction from same stain sections. Setting and Design: The different strategies have been evaluated on two liver specimens (80 sections in total stained with Hematoxylin and Eosin (H and E, Sirius Red, and Cytokeratin (CK 7. Results and Conclusion: A strategy of using multi-stain registration to align images of a second stain to a volume reconstructed by same-stain registration results in the lowest overall error, although an interlaced image registration approach may be more robust to poor section quality.

  1. WE-D-18A-05: Construction of Realistic Liver Phantoms From Patient Images and a Commercial 3D Printer

    Energy Technology Data Exchange (ETDEWEB)

    Leng, S; Vrieze, T; Kuhlmann, J; Yu, L; Matsumoto, J; Morris, J; McCollough, C [Mayo Clinic, Rochester, MN (United States)

    2014-06-15

    Purpose: To assess image quality and radiation dose reduction in abdominal CT imaging, physical phantoms having realistic background textures and lesions are highly desirable. The purpose of this work was to construct a liver phantom with realistic background and lesions using patient CT images and a 3D printer. Methods: Patient CT images containing liver lesions were segmented into liver tissue, contrast-enhanced vessels, and liver lesions using commercial software (Mimics, Materialise, Belgium). Stereolithography (STL) files of each segmented object were created and imported to a 3D printer (Object350 Connex, Stratasys, MN). After test scans were performed to map the eight available printing materials into CT numbers, printing materials were assigned to each object and a physical liver phantom printed. The printed phantom was scanned on a clinical CT scanner and resulting images were compared with the original patient CT images. Results: The eight available materials used to print the liver phantom had CT number ranging from 62 to 117 HU. In scans of the liver phantom, the liver lesions and veins represented in the STL files were all visible. Although the absolute value of the CT number in the background liver material (approx. 85 HU) was higher than in patients (approx. 40 HU), the difference in CT numbers between lesions and background were representative of the low contrast values needed for optimization tasks. Future work will investigate materials with contrast sufficient to emulate contrast-enhanced arteries. Conclusion: Realistic liver phantoms can be constructed from patient CT images using a commercial 3D printer. This technique may provide phantoms able to determine the effect of radiation dose reduction and noise reduction techniques on the ability to detect subtle liver lesions in the context of realistic background textures.

  2. Volume estimation of tonsil phantoms using an oral camera with 3D imaging.

    Science.gov (United States)

    Das, Anshuman J; Valdez, Tulio A; Vargas, Jose Arbouin; Saksupapchon, Punyapat; Rachapudi, Pushyami; Ge, Zhifei; Estrada, Julio C; Raskar, Ramesh

    2016-04-01

    Three-dimensional (3D) visualization of oral cavity and oropharyngeal anatomy may play an important role in the evaluation for obstructive sleep apnea (OSA). Although computed tomography (CT) and magnetic resonance (MRI) imaging are capable of providing 3D anatomical descriptions, this type of technology is not readily available in a clinic setting. Current imaging of the oropharynx is performed using a light source and tongue depressors. For better assessment of the inferior pole of the tonsils and tongue base flexible laryngoscopes are required which only provide a two dimensional (2D) rendering. As a result, clinical diagnosis is generally subjective in tonsillar hypertrophy where current physical examination has limitations. In this report, we designed a hand held portable oral camera with 3D imaging capability to reconstruct the anatomy of the oropharynx in tonsillar hypertrophy where the tonsils get enlarged and can lead to increased airway resistance. We were able to precisely reconstruct the 3D shape of the tonsils and from that estimate airway obstruction percentage and volume of the tonsils in 3D printed realistic models. Our results correlate well with Brodsky's classification of tonsillar hypertrophy as well as intraoperative volume estimations.

  3. Volume estimation of tonsil phantoms using an oral camera with 3D imaging

    Science.gov (United States)

    Das, Anshuman J.; Valdez, Tulio A.; Vargas, Jose Arbouin; Saksupapchon, Punyapat; Rachapudi, Pushyami; Ge, Zhifei; Estrada, Julio C.; Raskar, Ramesh

    2016-01-01

    Three-dimensional (3D) visualization of oral cavity and oropharyngeal anatomy may play an important role in the evaluation for obstructive sleep apnea (OSA). Although computed tomography (CT) and magnetic resonance (MRI) imaging are capable of providing 3D anatomical descriptions, this type of technology is not readily available in a clinic setting. Current imaging of the oropharynx is performed using a light source and tongue depressors. For better assessment of the inferior pole of the tonsils and tongue base flexible laryngoscopes are required which only provide a two dimensional (2D) rendering. As a result, clinical diagnosis is generally subjective in tonsillar hypertrophy where current physical examination has limitations. In this report, we designed a hand held portable oral camera with 3D imaging capability to reconstruct the anatomy of the oropharynx in tonsillar hypertrophy where the tonsils get enlarged and can lead to increased airway resistance. We were able to precisely reconstruct the 3D shape of the tonsils and from that estimate airway obstruction percentage and volume of the tonsils in 3D printed realistic models. Our results correlate well with Brodsky’s classification of tonsillar hypertrophy as well as intraoperative volume estimations. PMID:27446667

  4. The CT-PPS tracking system with 3D pixel detectors

    Science.gov (United States)

    Ravera, F.

    2016-11-01

    The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) detector will be installed in Roman pots (RP) positioned on either side of CMS, at about 210 m from the interaction point. This detector will measure leading protons, allowing detailed studies of diffractive physics and central exclusive production in standard LHC running conditions. An essential component of the CT-PPS apparatus is the tracking system, which consists of two detector stations per arm equipped with six 3D silicon pixel-sensor modules, each read out by six PSI46dig chips. The front-end electronics has been designed to fulfill the mechanical constraints of the RP and to be compatible as much as possible with the readout chain of the CMS pixel detector. The tracking system is currently under construction and will be installed by the end of 2016. In this contribution the final design and the expected performance of the CT-PPS tracking system is presented. A summary of the studies performed, before and after irradiation, on the 3D detectors produced for CT-PPS is given.

  5. The stylohyoid chain: CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uysal Ramadan, Selma, E-mail: uysalselma@yahoo.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Goekharman, Dilek, E-mail: gokharman@ttnet.net.t [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Kosar, Pinar, E-mail: pkosar@hotmail.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Kacar, Mahmut, E-mail: mkacar1961@gamil.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey); Kosar, Ugur, E-mail: ugurkosar@hotmail.co [Department of Radiology, Ankara Training and Research Hospital, Ankara 06590 (Turkey)

    2010-09-15

    We aimed in this report to discuss the embryology, anatomy, theories of ossification and symptoms, clinical presentation, and diagnosis of the stylohyoid chain (SHC) variations, together with the role of radiographs, computed tomography (CT) and three-dimensional (3D)-CT in showing these variations. Because CT/3D-CT additionally facilitates visualization of the entire SHC with different axes, it is the most valuable method for establishing the relationship between the SHC and the surrounding tissue. SHC variation can be discovered during CT performed for indications other than ossified SHC. It is important to diagnose whether or not the SHC is ossified, since one of the treatment procedures in ossified SHC is total excision. If the clinician and radiologist are aware of these variations observed in the SHC, patients with vague symptoms may be spared unnecessary investigations and may be properly diagnosed earlier.

  6. Three-dimensional multislice CT imaging of otitis media

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Miyako [Yanagibasi Hospital, Tokyo (Japan); Yoshikawa, Hiroshi; Hosokawa, Akira; Furukawa, Tomoyasu; Ichikawa, Ginichiro [Juntendo Univ., Tokyo (Japan). School of Medicine; Wada, Akihiro; Ando, Ichiro [Juntendo Univ., Chiba (Japan). Urayasu Hospital

    2002-07-01

    In recent years, the multislice CT system has come into practical use that enables table movement of half mm, resulting in a significant improvement in resolution. The use of this CT system enables to depict the entire auditory ossicles, including the stapes. 3D reconstruction was performed using helical CT data in 5 patients with chronic otitis media and 5 patients with cholesteatoma. An Aquilion Multi (Toshiba) multislice helical CT scanner and a Xtension (Toshiba) image workstation were used in this study. We demonstrated the 3D display with axial, coronal and sagittal images. Compared with the normal ears, it was necessary to set a higher threshold for the affected ears. It is important to select suitable threshold for demonstration of 3D images optimally. Bone destruction of the stapes was confirmed at surgery in 2 ears. The stapes was observed at 3D-CT imaging in other 18 ears. It was found that the 3D images of the ossicular destruction in ears with cholesteatoma were consistent with surgical findings. It is therefore concluded that 3D imaging of the middle ear using a multislice CT scanner is clinically useful. (author)

  7. Underwater 3d Modeling: Image Enhancement and Point Cloud Filtering

    Science.gov (United States)

    Sarakinou, I.; Papadimitriou, K.; Georgoula, O.; Patias, P.

    2016-06-01

    This paper examines the results of image enhancement and point cloud filtering on the visual and geometric quality of 3D models for the representation of underwater features. Specifically it evaluates the combination of effects from the manual editing of images' radiometry (captured at shallow depths) and the selection of parameters for point cloud definition and mesh building (processed in 3D modeling software). Such datasets, are usually collected by divers, handled by scientists and used for geovisualization purposes. In the presented study, have been created 3D models from three sets of images (seafloor, part of a wreck and a small boat's wreck) captured at three different depths (3.5m, 10m and 14m respectively). Four models have been created from the first dataset (seafloor) in order to evaluate the results from the application of image enhancement techniques and point cloud filtering. The main process for this preliminary study included a) the definition of parameters for the point cloud filtering and the creation of a reference model, b) the radiometric editing of images, followed by the creation of three improved models and c) the assessment of results by comparing the visual and the geometric quality of improved models versus the reference one. Finally, the selected technique is tested on two other data sets in order to examine its appropriateness for different depths (at 10m and 14m) and different objects (part of a wreck and a small boat's wreck) in the context of an ongoing research in the Laboratory of Photogrammetry and Remote Sensing.

  8. Feature detection on 3D images of dental imprints

    Science.gov (United States)

    Mokhtari, Marielle; Laurendeau, Denis

    1994-09-01

    A computer vision approach for the extraction of feature points on 3D images of dental imprints is presented. The position of feature points are needed for the measurement of a set of parameters for automatic diagnosis of malocclusion problems in orthodontics. The system for the acquisition of the 3D profile of the imprint, the procedure for the detection of the interstices between teeth, and the approach for the identification of the type of tooth are described, as well as the algorithm for the reconstruction of the surface of each type of tooth. A new approach for the detection of feature points, called the watershed algorithm, is described in detail. The algorithm is a two-stage procedure which tracks the position of local minima at four different scales and produces a final map of the position of the minima. Experimental results of the application of the watershed algorithm on actual 3D images of dental imprints are presented for molars, premolars and canines. The segmentation approach for the analysis of the shape of incisors is also described in detail.

  9. Phase Sensitive Cueing for 3D Objects in Overhead Images

    Energy Technology Data Exchange (ETDEWEB)

    Paglieroni, D W; Eppler, W G; Poland, D N

    2005-02-18

    A 3D solid model-aided object cueing method that matches phase angles of directional derivative vectors at image pixels to phase angles of vectors normal to projected model edges is described. It is intended for finding specific types of objects at arbitrary position and orientation in overhead images, independent of spatial resolution, obliqueness, acquisition conditions, and type of imaging sensor. It is shown that the phase similarity measure can be efficiently evaluated over all combinations of model position and orientation using the FFT. The highest degree of similarity over all model orientations is captured in a match surface of similarity values vs. model position. Unambiguous peaks in this surface are sorted in descending order of similarity value, and the small image thumbnails that contain them are presented to human analysts for inspection in sorted order.

  10. 3D Lunar Terrain Reconstruction from Apollo Images

    Science.gov (United States)

    Broxton, Michael J.; Nefian, Ara V.; Moratto, Zachary; Kim, Taemin; Lundy, Michael; Segal, Alkeksandr V.

    2009-01-01

    Generating accurate three dimensional planetary models is becoming increasingly important as NASA plans manned missions to return to the Moon in the next decade. This paper describes a 3D surface reconstruction system called the Ames Stereo Pipeline that is designed to produce such models automatically by processing orbital stereo imagery. We discuss two important core aspects of this system: (1) refinement of satellite station positions and pose estimates through least squares bundle adjustment; and (2) a stochastic plane fitting algorithm that generalizes the Lucas-Kanade method for optimal matching between stereo pair images.. These techniques allow us to automatically produce seamless, highly accurate digital elevation models from multiple stereo image pairs while significantly reducing the influence of image noise. Our technique is demonstrated on a set of 71 high resolution scanned images from the Apollo 15 mission

  11. Analysis of the Geometry of the Distal Femur and Proximal Tibia in the Osteoarthritic Knee: A 3D Reconstruction CT Scan Based Study of 449 Cases

    OpenAIRE

    Dimitrios Lyras; Craig Loucks; Robert Greenhow

    2016-01-01

    Background: The aim of this study is to evaluate the geometry of the distal femur and the proximal tibia in the osteoarthritic knee using 3D reconstructive CT scan imaging. Methods: 449 patients with knee osteoarthritis were treated surgically in our center with patient-specific technology total knee arthroplasty. Preoperatively, all the patients underwent a CT scan according to a standard protocol. Using this database, the Hip-Knee-Angle (HKA), the Femur Valgus Angle (FVA), the Tibia Varus A...

  12. Computed Tomography Image Origin Identification based on Original Sensor Pattern Noise and 3D Image Reconstruction Algorithm Footprints.

    Science.gov (United States)

    Duan, Yuping; Bouslimi, Dalel; Yang, Guanyu; Shu, Huazhong; Coatrieux, Gouenou

    2016-06-08

    In this paper, we focus on the "blind" identification of the Computed Tomography (CT) scanner that has produced a CT image. To do so, we propose a set of noise features derived from the image chain acquisition and which can be used as CT-Scanner footprint. Basically, we propose two approaches. The first one aims at identifying a CT-Scanner based on an Original Sensor Pattern Noise (OSPN) that is intrinsic to the X-ray detectors. The second one identifies an acquisition system based on the way this noise is modified by its 3D image reconstruction algorithm. As these reconstruction algorithms are manufacturer dependent and kept secret, our features are used as input to train an SVM based classifier so as to discriminate acquisition systems. Experiments conducted on images issued from 15 different CT-Scanner models of 4 distinct manufacturers demonstrate that our system identifies the origin of one CT image with a detection rate of at least 94% and that it achieves better performance than Sensor Pattern Noise (SPN) based strategy proposed for general public camera devices.

  13. FELIX 3D display: an interactive tool for volumetric imaging

    Science.gov (United States)

    Langhans, Knut; Bahr, Detlef; Bezecny, Daniel; Homann, Dennis; Oltmann, Klaas; Oltmann, Krischan; Guill, Christian; Rieper, Elisabeth; Ardey, Goetz

    2002-05-01

    The FELIX 3D display belongs to the class of volumetric displays using the swept volume technique. It is designed to display images created by standard CAD applications, which can be easily imported and interactively transformed in real-time by the FELIX control software. The images are drawn on a spinning screen by acousto-optic, galvanometric or polygon mirror deflection units with integrated lasers and a color mixer. The modular design of the display enables the user to operate with several equal or different projection units in parallel and to use appropriate screens for the specific purpose. The FELIX 3D display is a compact, light, extensible and easy to transport system. It mainly consists of inexpensive standard, off-the-shelf components for an easy implementation. This setup makes it a powerful and flexible tool to keep track with the rapid technological progress of today. Potential applications include imaging in the fields of entertainment, air traffic control, medical imaging, computer aided design as well as scientific data visualization.

  14. Development and comparison of projection and image space 3D nodule insertion techniques

    Science.gov (United States)

    Robins, Marthony; Solomon, Justin; Sahbaee, Pooyan; Samei, Ehsan

    2016-04-01

    This study aimed to develop and compare two methods of inserting computerized virtual lesions into CT datasets. 24 physical (synthetic) nodules of three sizes and four morphologies were inserted into an anthropomorphic chest phantom (LUNGMAN, KYOTO KAGAKU). The phantom was scanned (Somatom Definition Flash, Siemens Healthcare) with and without nodules present, and images were reconstructed with filtered back projection and iterative reconstruction (SAFIRE) at 0.6 mm slice thickness using a standard thoracic CT protocol at multiple dose settings. Virtual 3D CAD models based on the physical nodules were virtually inserted (accounting for the system MTF) into the nodule-free CT data using two techniques. These techniques include projection-based and image-based insertion. Nodule volumes were estimated using a commercial segmentation tool (iNtuition, TeraRecon, Inc.). Differences were tested using paired t-tests and R2 goodness of fit between the virtually and physically inserted nodules. Both insertion techniques resulted in nodule volumes very similar to the real nodules (<3% difference) and in most cases the differences were not statistically significant. Also, R2 values were all <0.97 for both insertion techniques. These data imply that these techniques can confidently be used as a means of inserting virtual nodules in CT datasets. These techniques can be instrumental in building hybrid CT datasets composed of patient images with virtually inserted nodules.

  15. Usefulness of 3D-image of ossicles with helical scanning

    Energy Technology Data Exchange (ETDEWEB)

    Makihata, Hiroshi; Kimura, Hideaki; Hanaguri, Katsurou; Fukushima, Noriyuki; Oda, Yukari [Chugoku Rousai Hospital, Kure, Hiroshima (Japan)

    1995-09-01

    It is important to understand the abnormalities of ossicles (continuity, destruction and malformation) in clinical practice of middle ear diseases. Multidirection exposures were needed to visualize ossicles with the conventional CT scanning, because they are visualized in 2D images. It was difficult to make patients hold the posture and to settle the problems such as an increase in X-ray dose. We created 3D images of ossicles with a helical scanning, and examined the visualization of the normal and abnormal ear (otitis media cholesteatoma) especially in terms of continuity in each of 20 patients. We would here like to report the favorable results together with some literature review. (author).

  16. UNDERWATER 3D MODELING: IMAGE ENHANCEMENT AND POINT CLOUD FILTERING

    Directory of Open Access Journals (Sweden)

    I. Sarakinou

    2016-06-01

    Full Text Available This paper examines the results of image enhancement and point cloud filtering on the visual and geometric quality of 3D models for the representation of underwater features. Specifically it evaluates the combination of effects from the manual editing of images’ radiometry (captured at shallow depths and the selection of parameters for point cloud definition and mesh building (processed in 3D modeling software. Such datasets, are usually collected by divers, handled by scientists and used for geovisualization purposes. In the presented study, have been created 3D models from three sets of images (seafloor, part of a wreck and a small boat's wreck captured at three different depths (3.5m, 10m and 14m respectively. Four models have been created from the first dataset (seafloor in order to evaluate the results from the application of image enhancement techniques and point cloud filtering. The main process for this preliminary study included a the definition of parameters for the point cloud filtering and the creation of a reference model, b the radiometric editing of images, followed by the creation of three improved models and c the assessment of results by comparing the visual and the geometric quality of improved models versus the reference one. Finally, the selected technique is tested on two other data sets in order to examine its appropriateness for different depths (at 10m and 14m and different objects (part of a wreck and a small boat's wreck in the context of an ongoing research in the Laboratory of Photogrammetry and Remote Sensing.

  17. Post-processing methods of rendering and visualizing 3-D reconstructed tomographic images

    Energy Technology Data Exchange (ETDEWEB)

    Wong, S.T.C. [Univ. of California, San Francisco, CA (United States)

    1997-02-01

    The purpose of this presentation is to discuss the computer processing techniques of tomographic images, after they have been generated by imaging scanners, for volume visualization. Volume visualization is concerned with the representation, manipulation, and rendering of volumetric data. Since the first digital images were produced from computed tomography (CT) scanners in the mid 1970s, applications of visualization in medicine have expanded dramatically. Today, three-dimensional (3D) medical visualization has expanded from using CT data, the first inherently digital source of 3D medical data, to using data from various medical imaging modalities, including magnetic resonance scanners, positron emission scanners, digital ultrasound, electronic and confocal microscopy, and other medical imaging modalities. We have advanced from rendering anatomy to aid diagnosis and visualize complex anatomic structures to planning and assisting surgery and radiation treatment. New, more accurate and cost-effective procedures for clinical services and biomedical research have become possible by integrating computer graphics technology with medical images. This trend is particularly noticeable in current market-driven health care environment. For example, interventional imaging, image-guided surgery, and stereotactic and visualization techniques are now stemming into surgical practice. In this presentation, we discuss only computer-display-based approaches of volumetric medical visualization. That is, we assume that the display device available is two-dimensional (2D) in nature and all analysis of multidimensional image data is to be carried out via the 2D screen of the device. There are technologies such as holography and virtual reality that do provide a {open_quotes}true 3D screen{close_quotes}. To confine the scope, this presentation will not discuss such approaches.

  18. 3D imaging by serial block face scanning electron microscopy for materials science using ultramicrotomy.

    Science.gov (United States)

    Hashimoto, Teruo; Thompson, George E; Zhou, Xiaorong; Withers, Philip J

    2016-04-01

    Mechanical serial block face scanning electron microscopy (SBFSEM) has emerged as a means of obtaining three dimensional (3D) electron images over volumes much larger than possible by focused ion beam (FIB) serial sectioning and at higher spatial resolution than achievable with conventional X-ray computed tomography (CT). Such high resolution 3D electron images can be employed for precisely determining the shape, volume fraction, distribution and connectivity of important microstructural features. While soft (fixed or frozen) biological samples are particularly well suited for nanoscale sectioning using an ultramicrotome, the technique can also produce excellent 3D images at electron microscope resolution in a time and resource-efficient manner for engineering materials. Currently, a lack of appreciation of the capabilities of ultramicrotomy and the operational challenges associated with minimising artefacts for different materials is limiting its wider application to engineering materials. Consequently, this paper outlines the current state of the art for SBFSEM examining in detail how damage is introduced during slicing and highlighting strategies for minimising such damage. A particular focus of the study is the acquisition of 3D images for a variety of metallic and coated systems.

  19. Towards real-time 3D US-CT registration on the beating heart for guidance of minimally invasive cardiac interventions

    Science.gov (United States)

    Li, Feng; Lang, Pencilla; Rajchl, Martin; Chen, Elvis C. S.; Guiraudon, Gerard; Peters, Terry M.

    2012-02-01

    Compared to conventional open-heart surgeries, minimally invasive cardiac interventions cause less trauma and sideeffects to patients. However, the direct view of surgical targets and tools is usually not available in minimally invasive procedures, which makes image-guided navigation systems essential. The choice of imaging modalities used in the navigation systems must consider the capability of imaging soft tissues, spatial and temporal resolution, compatibility and flexibility in the OR, and financial cost. In this paper, we propose a new means of guidance for minimally invasive cardiac interventions using 3D real-time ultrasound images to show the intra-operative heart motion together with preoperative CT image(s) employed to demonstrate high-quality 3D anatomical context. We also develop a method to register intra-operative ultrasound and pre-operative CT images in close to real-time. The registration method has two stages. In the first, anatomical features are segmented from the first frame of ultrasound images and the CT image(s). A feature based registration is used to align those features. The result of this is used as an initialization in the second stage, in which a mutual information based registration is used to register every ultrasound frame to the CT image(s). A GPU based implementation is used to accelerate the registration.

  20. Efficient and robust model-to-image alignment using 3D scale-invariant features.

    Science.gov (United States)

    Toews, Matthew; Wells, William M

    2013-04-01

    This paper presents feature-based alignment (FBA), a general method for efficient and robust model-to-image alignment. Volumetric images, e.g. CT scans of the human body, are modeled probabilistically as a collage of 3D scale-invariant image features within a normalized reference space. Features are incorporated as a latent random variable and marginalized out in computing a maximum a posteriori alignment solution. The model is learned from features extracted in pre-aligned training images, then fit to features extracted from a new image to identify a globally optimal locally linear alignment solution. Novel techniques are presented for determining local feature orientation and efficiently encoding feature intensity in 3D. Experiments involving difficult magnetic resonance (MR) images of the human brain demonstrate FBA achieves alignment accuracy similar to widely-used registration methods, while requiring a fraction of the memory and computation resources and offering a more robust, globally optimal solution. Experiments on CT human body scans demonstrate FBA as an effective system for automatic human body alignment where other alignment methods break down.

  1. X-Ray Nanofocus CT: Visualising Of Internal 3D-Structures With Submicrometer Resolution

    Science.gov (United States)

    Weinekoetter, Christian

    2008-09-01

    High-resolution X-ray Computed Tomography (CT) allows the visualization and failure analysis of the internal micro structure of objects—even if they have complicated 3D-structures where 2D X-ray microscopy would give unclear information. During the past several years, computed tomography has progressed to higher resolution and quicker reconstruction of the 3D-volume. Most recently it even allows a three-dimensional look into the inside of materials with submicron resolution. With the use of nanofocus® tube technology, nanoCT®-systems are pushing forward into application fields that were exclusive to high cost and rare available synchrotron techniques. The study was performed with the new nanotom, a very compact laboratory system which allows the analysis of samples up to 120 mm in diameter and weighing up to 1 kg with exceptional voxel-resolution down to click, this technique will substitute destructive mechanical slicing and cutting in many applications. The initial CT results obtained with the nanotom® demonstrate that it is now possible to analyze the three-dimensional micro structure of materials and small objects with submicrometer resolution. Any internal difference in material, density or porosity within a sample can be visualized and data like distances can be measured. NanoCT® widely expands the spectrum of detectable micro-structures. The nanotom® opens a new dimension of 3D-microanalysis and will replace more destructive methods—saving costs and time per sample inspected.

  2. The CT-PPS tracking system with 3D pixel detectors

    CERN Document Server

    Ravera, Fabio

    2016-01-01

    The CMS-TOTEM Precision Proton Spectrometer (CT-PPS) detector will be installed in Roman pots (RP) positioned on either side of CMS, at about 200 m from the interaction point. This detector will measure forward leading protons, allowing detailed studies of diffractive physics and central exclusive production in standard LHC running conditions. An essential component of the CT-PPS apparatus is the tracking system, which consists of two detector stations per arm equipped with six 3D silicon pixel-sensor modules, each read out by six PSI46dig chips. The front-end electronics has been designed to fulfill the mechanical constrains of the RP and to be compatible as much as possible with the readout chain of the CMS pixel detector. The tracking system is currently under construction and will be installed by the end of 2016. In this contribution the final design and the expected performance of the CT-PPS tracking system will be presented. A summary of the studies performed, before and after irradiation, on the 3D det...

  3. High-resolution 3D X-ray imaging of intracranial nitinol stents

    Energy Technology Data Exchange (ETDEWEB)

    Snoeren, Rudolph M.; With, Peter H.N. de [Eindhoven University of Technology (TU/e), Faculty Electrical Engineering, Signal Processing Systems group (SPS), Eindhoven (Netherlands); Soederman, Michael [Karolinska University Hospital, Department of Neuroradiology, Stockholm (Sweden); Kroon, Johannes N.; Roijers, Ruben B.; Babic, Drazenko [Philips Healthcare, Best (Netherlands)

    2012-02-15

    To assess an optimized 3D imaging protocol for intracranial nitinol stents in 3D C-arm flat detector imaging. For this purpose, an image quality simulation and an in vitro study was carried out. Nitinol stents of various brands were placed inside an anthropomorphic head phantom, using iodine contrast. Experiments with objects were preceded by image quality and dose simulations. We varied X-ray imaging parameters in a commercially interventional X-ray system to set 3D image quality in the contrast-noise-sharpness space. Beam quality was varied to evaluate contrast of the stents while keeping absorbed dose below recommended values. Two detector formats were used, paired with an appropriate pixel size and X-ray focus size. Zoomed reconstructions were carried out and snapshot images acquired. High contrast spatial resolution was assessed with a CT phantom. We found an optimal protocol for imaging intracranial nitinol stents. Contrast resolution was optimized for nickel-titanium-containing stents. A high spatial resolution larger than 2.1 lp/mm allows struts to be visualized. We obtained images of stents of various brands and a representative set of images is shown. Independent of the make, struts can be imaged with virtually continuous strokes. Measured absorbed doses are shown to be lower than 50 mGy Computed Tomography Dose Index (CTDI). By balancing the modulation transfer of the imaging components and tuning the high-contrast imaging capabilities, we have shown that thin nitinol stent wires can be reconstructed with high contrast-to-noise ratio and good detail, while keeping radiation doses within recommended values. Experimental results compare well with imaging simulations. (orig.)

  4. 3D-Image Fusion Experiment of Cross [PT+CT] Modality Based on Localization Registration Approach of "9-Point & 3-Plane"%基于"9点3面"配准方案的[PT+CT]异机三维图像融合实验

    Institute of Scientific and Technical Information of China (English)

    彭鳒侨; 丘红英; 董伟强; 刘襄平; 晏颖; 刘琦

    2011-01-01

    目的:尝试一种基于体表定位的二维图像配准方法,实现 PT和CT异机三维(3D)图像的精确融合.方法:输入PT/CT原始数据后采用数字化格式转换,设计"9点3面"立体定位法进行配准,在实时工作站Mimics按照信息交互自动融合模式,通过讯号叠加技术完成图像融合.结果:以肺癌患者的躯干冠状面为实例试验[PT+CT]立体图像的异机融合,生成了同时呈现躯干结构和代谢状况的互补3D影像.结论:在[PT+CT]联机设备尚未普及尤其是[PT+CT]3D融合仍未实现的情况下,[PT+CT]异机3D融合是[PT+CT]同机2D融合技术功用的必要补充.

  5. 3D IMAGING OF INDIVIDUAL PARTICLES: A REVIEW

    Directory of Open Access Journals (Sweden)

    Eric Pirard

    2012-06-01

    Full Text Available In recent years, impressive progress has been made in digital imaging and in particular in three dimensional visualisation and analysis of objects. This paper reviews the most recent literature on three dimensional imaging with a special attention to particulate systems analysis. After an introduction recalling some important concepts in spatial sampling and digital imaging, the paper reviews a series of techniques with a clear distinction between the surfometric and volumetric principles. The literature review is as broad as possible covering materials science as well as biology while keeping an eye on emerging technologies in optics and physics. The paper should be of interest to any scientist trying to picture particles in 3D with the best possible resolution for accurate size and shape estimation. Though techniques are adequate for nanoscopic and microscopic particles, no special size limit has been considered while compiling the review.

  6. Development of 3D microwave imaging reflectometry in LHD (invited).

    Science.gov (United States)

    Nagayama, Y; Kuwahara, D; Yoshinaga, T; Hamada, Y; Kogi, Y; Mase, A; Tsuchiya, H; Tsuji-Iio, S; Yamaguchi, S

    2012-10-01

    Three-dimensional (3D) microwave imaging reflectometry has been developed in the large helical device to visualize fluctuating reflection surface which is caused by the density fluctuations. The plasma is illuminated by the probe wave with four frequencies, which correspond to four radial positions. The imaging optics makes the image of cut-off surface onto the 2D (7 × 7 channels) horn antenna mixer arrays. Multi-channel receivers have been also developed using micro-strip-line technology to handle many channels at reasonable cost. This system is first applied to observe the edge harmonic oscillation (EHO), which is an MHD mode with many harmonics that appears in the edge plasma. A narrow structure along field lines is observed during EHO.

  7. Low cost 3D scanning process using digital image processing

    Science.gov (United States)

    Aguilar, David; Romero, Carlos; Martínez, Fernando

    2017-02-01

    This paper shows the design and building of a low cost 3D scanner, able to digitize solid objects through contactless data acquisition, using active object reflection. 3D scanners are used in different applications such as: science, engineering, entertainment, etc; these are classified in: contact scanners and contactless ones, where the last ones are often the most used but they are expensive. This low-cost prototype is done through a vertical scanning of the object using a fixed camera and a mobile horizontal laser light, which is deformed depending on the 3-dimensional surface of the solid. Using digital image processing an analysis of the deformation detected by the camera was done; it allows determining the 3D coordinates using triangulation. The obtained information is processed by a Matlab script, which gives to the user a point cloud corresponding to each horizontal scanning done. The obtained results show an acceptable quality and significant details of digitalized objects, making this prototype (built on LEGO Mindstorms NXT kit) a versatile and cheap tool, which can be used for many applications, mainly by engineering students.

  8. Effective classification of 3D image data using partitioning methods

    Science.gov (United States)

    Megalooikonomou, Vasileios; Pokrajac, Dragoljub; Lazarevic, Aleksandar; Obradovic, Zoran

    2002-03-01

    We propose partitioning-based methods to facilitate the classification of 3-D binary image data sets of regions of interest (ROIs) with highly non-uniform distributions. The first method is based on recursive dynamic partitioning of a 3-D volume into a number of 3-D hyper-rectangles. For each hyper-rectangle, we consider, as a potential attribute, the number of voxels (volume elements) that belong to ROIs. A hyper-rectangle is partitioned only if the corresponding attribute does not have high discriminative power, determined by statistical tests, but it is still sufficiently large for further splitting. The final discriminative hyper-rectangles form new attributes that are further employed in neural network classification models. The second method is based on maximum likelihood employing non-spatial (k-means) and spatial DBSCAN clustering algorithms to estimate the parameters of the underlying distributions. The proposed methods were experimentally evaluated on mixtures of Gaussian distributions, on realistic lesion-deficit data generated by a simulator conforming to a clinical study, and on synthetic fractal data. Both proposed methods have provided good classification on Gaussian mixtures and on realistic data. However, the experimental results on fractal data indicated that the clustering-based methods were only slightly better than random guess, while the recursive partitioning provided significantly better classification accuracy.

  9. Physically based analysis of deformations in 3D images

    Science.gov (United States)

    Nastar, Chahab; Ayache, Nicholas

    1993-06-01

    We present a physically based deformable model which can be used to track and to analyze the non-rigid motion of dynamic structures in time sequences of 2-D or 3-D medical images. The model considers an object undergoing an elastic deformation as a set of masses linked by springs, where the natural lengths of the springs is set equal to zero, and is replaced by a set of constant equilibrium forces, which characterize the shape of the elastic structure in the absence of external forces. This model has the extremely nice property of yielding dynamic equations which are linear and decoupled for each coordinate, whatever the amplitude of the deformation. It provides a reduced algorithmic complexity, and a sound framework for modal analysis, which allows a compact representation of a general deformation by a reduced number of parameters. The power of the approach to segment, track, and analyze 2-D and 3-D images is demonstrated by a set of experimental results on various complex medical images.

  10. Image-Based 3D Face Modeling System

    Directory of Open Access Journals (Sweden)

    Vladimir Vezhnevets

    2005-08-01

    Full Text Available This paper describes an automatic system for 3D face modeling using frontal and profile images taken by an ordinary digital camera. The system consists of four subsystems including frontal feature detection, profile feature detection, shape deformation, and texture generation modules. The frontal and profile feature detection modules automatically extract the facial parts such as the eye, nose, mouth, and ear. The shape deformation module utilizes the detected features to deform the generic head mesh model such that the deformed model coincides with the detected features. A texture is created by combining the facial textures augmented from the input images and the synthesized texture and mapped onto the deformed generic head model. This paper provides a practical system for 3D face modeling, which is highly automated by aggregating, customizing, and optimizing a bunch of individual computer vision algorithms. The experimental results show a highly automated process of modeling, which is sufficiently robust to various imaging conditions. The whole model creation including all the optional manual corrections takes only 2∼3 minutes.

  11. [Rapid 2D-3D medical image registration based on CUDA].

    Science.gov (United States)

    Li, Lingzhi; Zou, Beiji

    2014-08-01

    The medical image registration between preoperative three-dimensional (3D) scan data and intraoperative two-dimensional (2D) image is a key technology in the surgical navigation. Most previous methods need to generate 2D digitally reconstructed radiographs (DRR) images from the 3D scan volume data, then use conventional image similarity function for comparison. This procedure includes a large amount of calculation and is difficult to archive real-time processing. In this paper, with using geometric feature and image density mixed characteristics, we proposed a new similarity measure function for fast 2D-3D registration of preoperative CT and intraoperative X-ray images. This algorithm is easy to implement, and the calculation process is very short, while the resulting registration accuracy can meet the clinical use. In addition, the entire calculation process is very suitable for highly parallel numerical calculation by using the algorithm based on CUDA hardware acceleration to satisfy the requirement of real-time application in surgery.

  12. 3D imaging of neutron tracks using confocal microscopy

    Science.gov (United States)

    Gillmore, Gavin; Wertheim, David; Flowers, Alan

    2016-04-01

    Neutron detection and neutron flux assessment are important aspects in monitoring nuclear energy production. Neutron flux measurements can also provide information on potential biological damage from exposure. In addition to the applications for neutron measurement in nuclear energy, neutron detection has been proposed as a method of enhancing neutrino detectors and cosmic ray flux has also been assessed using ground-level neutron detectors. Solid State Nuclear Track Detectors (or SSNTDs) have been used extensively to examine cosmic rays, long-lived radioactive elements, radon concentrations in buildings and the age of geological samples. Passive SSNTDs consisting of a CR-39 plastic are commonly used to measure radon because they respond to incident charged particles such as alpha particles from radon gas in air. They have a large dynamic range and a linear flux response. We have previously applied confocal microscopy to obtain 3D images of alpha particle tracks in SSNTDs from radon track monitoring (1). As a charged particle traverses through the polymer it creates an ionisation trail along its path. The trail or track is normally enhanced by chemical etching to better expose radiation damage, as the damaged area is more sensitive to the etchant than the bulk material. Particle tracks in CR-39 are usually assessed using 2D optical microscopy. In this study 6 detectors were examined using an Olympus OLS4100 LEXT 3D laser scanning confocal microscope (Olympus Corporation, Japan). The detectors had been etched for 2 hours 50 minutes at 85 °C in 6.25M NaOH. Post etch the plastics had been treated with a 10 minute immersion in a 2% acetic acid stop bath, followed by rinsing in deionised water. The detectors examined had been irradiated with a 2mSv neutron dose from an Am(Be) neutron source (producing roughly 20 tracks per mm2). We were able to successfully acquire 3D images of neutron tracks in the detectors studied. The range of track diameter observed was between 4

  13. Extracting 3D layout from a single image using global image structures.

    Science.gov (United States)

    Lou, Zhongyu; Gevers, Theo; Hu, Ninghang

    2015-10-01

    Extracting the pixel-level 3D layout from a single image is important for different applications, such as object localization, image, and video categorization. Traditionally, the 3D layout is derived by solving a pixel-level classification problem. However, the image-level 3D structure can be very beneficial for extracting pixel-level 3D layout since it implies the way how pixels in the image are organized. In this paper, we propose an approach that first predicts the global image structure, and then we use the global structure for fine-grained pixel-level 3D layout extraction. In particular, image features are extracted based on multiple layout templates. We then learn a discriminative model for classifying the global layout at the image-level. Using latent variables, we implicitly model the sublevel semantics of the image, which enrich the expressiveness of our model. After the image-level structure is obtained, it is used as the prior knowledge to infer pixel-wise 3D layout. Experiments show that the results of our model outperform the state-of-the-art methods by 11.7% for 3D structure classification. Moreover, we show that employing the 3D structure prior information yields accurate 3D scene layout segmentation.

  14. Performance of an improved first generation optical CT scanner for 3D dosimetry.

    Science.gov (United States)

    Qian, Xin; Adamovics, John; Wuu, Cheng-Shie

    2013-12-21

    Performance analysis of a modified 3D dosimetry optical scanner based on the first generation optical CT scanner OCTOPUS is presented. The system consists of PRESAGE dosimeters, the modified 3D scanner, and a new developed in-house user control panel written in Labview program which provides more flexibility to optimize mechanical control and data acquisition technique. The total scanning time has been significantly reduced from initial 8 h to ∼2 h by using the modified scanner. The functional performance of the modified scanner has been evaluated in terms of the mechanical integrity uncertainty of the data acquisition process. Optical density distribution comparison between the modified scanner, OCTOPUS and the treatment plan system has been studied. It has been demonstrated that the agreement between the modified scanner and treatment plans is comparable with that between the OCTOPUS and treatment plans.

  15. Robust method for extracting the pulmonary vascular trees from 3D MDCT images

    Science.gov (United States)

    Taeprasartsit, Pinyo; Higgins, William E.

    2011-03-01

    Segmentation of pulmonary blood vessels from three-dimensional (3D) multi-detector CT (MDCT) images is important for pulmonary applications. This work presents a method for extracting the vascular trees of the pulmonary arteries and veins, applicable to both contrast-enhanced and unenhanced 3D MDCT image data. The method finds 2D elliptical cross-sections and evaluates agreement of these cross-sections in consecutive slices to find likely cross-sections. It next employs morphological multiscale analysis to separate vessels from adjoining airway walls. The method then tracks the center of the likely cross-sections to connect them to the pulmonary vessels in the mediastinum and forms connected vascular trees spanning both lungs. A ground-truth study indicates that the method was able to detect on the order of 98% of the vessel branches having diameter >= 3.0 mm. The extracted vascular trees can be utilized for the guidance of safe bronchoscopic biopsy.

  16. A new approach of building 3D visualization framework for multimodal medical images display and computed assisted diagnosis

    Science.gov (United States)

    Li, Zhenwei; Sun, Jianyong; Zhang, Jianguo

    2012-02-01

    As more and more CT/MR studies are scanning with larger volume of data sets, more and more radiologists and clinician would like using PACS WS to display and manipulate these larger data sets of images with 3D rendering features. In this paper, we proposed a design method and implantation strategy to develop 3D image display component not only with normal 3D display functions but also with multi-modal medical image fusion as well as compute-assisted diagnosis of coronary heart diseases. The 3D component has been integrated into the PACS display workstation of Shanghai Huadong Hospital, and the clinical practice showed that it is easy for radiologists and physicians to use these 3D functions such as multi-modalities' (e.g. CT, MRI, PET, SPECT) visualization, registration and fusion, and the lesion quantitative measurements. The users were satisfying with the rendering speeds and quality of 3D reconstruction. The advantages of the component include low requirements for computer hardware, easy integration, reliable performance and comfortable application experience. With this system, the radiologists and the clinicians can manipulate with 3D images easily, and use the advanced visualization tools to facilitate their work with a PACS display workstation at any time.

  17. Neural network and its application to CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Nikravesh, M.; Kovscek, A.R.; Patzek, T.W. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-02-01

    We present an integrated approach to imaging the progress of air displacement by spontaneous imbibition of oil into sandstone. We combine Computerized Tomography (CT) scanning and neural network image processing. The main aspects of our approach are (I) visualization of the distribution of oil and air saturation by CT, (II) interpretation of CT scans using neural networks, and (III) reconstruction of 3-D images of oil saturation from the CT scans with a neural network model. Excellent agreement between the actual images and the neural network predictions is found.

  18. 3D painting documentation: evaluation of conservation conditions with 3D imaging and ranging techniques

    Science.gov (United States)

    Abate, D.; Menna, F.; Remondino, F.; Gattari, M. G.

    2014-06-01

    The monitoring of paintings, both on canvas and wooden support, is a crucial issue for the preservation and conservation of this kind of artworks. Many environmental factors (e.g. humidity, temperature, illumination, etc.), as well as bad conservation practices (e.g. wrong restorations, inappropriate locations, etc.), can compromise the material conditions over time and deteriorate an artwork. The article presents an on-going project realized by a multidisciplinary team composed by the ENEA UTICT 3D GraphLab, the 3D Optical Metrology Unit of the Bruno Kessler Foundation and the Soprintendenza per i Beni Storico Artistici ed Etnoantropologici of Bologna (Italy). The goal of the project is the multi-temporal 3D documentation and monitoring of paintings - at the moment in bad conservation's situation - and the provision of some metrics to quantify the deformations and damages.

  19. Is 3D-CT reformation using free software applicable to diagnosis of bone changes in mandibular condyles?

    Directory of Open Access Journals (Sweden)

    Marília Gerhardt de Oliveira

    2009-06-01

    Full Text Available OBJECTIVES: This study evaluated the agreement of computed tomography (CT imaging using 3D reformations (3DR with shaded surface display (SSD and maximum intensity projection (MIP in the diagnosis of bone changes in mandibular condyles of patients with rheumatoid arthritis (RA, and compared findings with multiplanar reformation (MPR images, used as the criterion standard. MATERIAL AND METHODS: Axial CT images of 44 temporomandibular joints (TMJs of 22 patients with RA were used. Images were recorded in DICOM format and assessed using free software (ImageJ. Each sample had its 3DR-SSD and 3DR-MIP results compared in pairs with the MPR results. RESULTS: Slight agreement (k = 0.0374 was found in almost all comparisons. The level of agreement showed that 3DR-SSD and 3DR-MIP yielded a number of false-negative results that was statistically significant when compared with MPR. CONCLUSIONS: 3DR-SSD or 3DR-MIP should only be used as adjuvant techniques to MPR in the diagnosis of bone changes in mandibular condyles.

  20. 3D-2D Deformable Image Registration Using Feature-Based Nonuniform Meshes.

    Science.gov (United States)

    Zhong, Zichun; Guo, Xiaohu; Cai, Yiqi; Yang, Yin; Wang, Jing; Jia, Xun; Mao, Weihua

    2016-01-01

    By using prior information of planning CT images and feature-based nonuniform meshes, this paper demonstrates that volumetric images can be efficiently registered with a very small portion of 2D projection images of a Cone-Beam Computed Tomography (CBCT) scan. After a density field is computed based on the extracted feature edges from planning CT images, nonuniform tetrahedral meshes will be automatically generated to better characterize the image features according to the density field; that is, finer meshes are generated for features. The displacement vector fields (DVFs) are specified at the mesh vertices to drive the deformation of original CT images. Digitally reconstructed radiographs (DRRs) of the deformed anatomy are generated and compared with corresponding 2D projections. DVFs are optimized to minimize the objective function including differences between DRRs and projections and the regularity. To further accelerate the above 3D-2D registration, a procedure to obtain good initial deformations by deforming the volume surface to match 2D body boundary on projections has been developed. This complete method is evaluated quantitatively by using several digital phantoms and data from head and neck cancer patients. The feature-based nonuniform meshing method leads to better results than either uniform orthogonal grid or uniform tetrahedral meshes.

  1. 3D-2D Deformable Image Registration Using Feature-Based Nonuniform Meshes

    Directory of Open Access Journals (Sweden)

    Zichun Zhong

    2016-01-01

    Full Text Available By using prior information of planning CT images and feature-based nonuniform meshes, this paper demonstrates that volumetric images can be efficiently registered with a very small portion of 2D projection images of a Cone-Beam Computed Tomography (CBCT scan. After a density field is computed based on the extracted feature edges from planning CT images, nonuniform tetrahedral meshes will be automatically generated to better characterize the image features according to the density field; that is, finer meshes are generated for features. The displacement vector fields (DVFs are specified at the mesh vertices to drive the deformation of original CT images. Digitally reconstructed radiographs (DRRs of the deformed anatomy are generated and compared with corresponding 2D projections. DVFs are optimized to minimize the objective function including differences between DRRs and projections and the regularity. To further accelerate the above 3D-2D registration, a procedure to obtain good initial deformations by deforming the volume surface to match 2D body boundary on projections has been developed. This complete method is evaluated quantitatively by using several digital phantoms and data from head and neck cancer patients. The feature-based nonuniform meshing method leads to better results than either uniform orthogonal grid or uniform tetrahedral meshes.

  2. Experiments on terahertz 3D scanning microscopic imaging

    Science.gov (United States)

    Zhou, Yi; Li, Qi

    2016-10-01

    Compared with the visible light and infrared, terahertz (THz) radiation can penetrate nonpolar and nonmetallic materials. There are many studies on the THz coaxial transmission confocal microscopy currently. But few researches on the THz dual-axis reflective confocal microscopy were reported. In this paper, we utilized a dual-axis reflective confocal scanning microscope working at 2.52 THz. In contrast with the THz coaxial transmission confocal microscope, the microscope adopted in this paper can attain higher axial resolution at the expense of reduced lateral resolution, revealing more satisfying 3D imaging capability. Objects such as Chinese characters "Zhong-Hua" written in paper with a pencil and a combined sheet metal which has three layers were scanned. The experimental results indicate that the system can extract two Chinese characters "Zhong," "Hua" or three layers of the combined sheet metal. It can be predicted that the microscope can be applied to biology, medicine and other fields in the future due to its favorable 3D imaging capability.

  3. 3D analytic cone-beam reconstruction for multiaxial CT acquisitions.

    Science.gov (United States)

    Yin, Zhye; De Man, Bruno; Pack, Jed

    2009-01-01

    A conventional 3rd generation Computed Tomography (CT) system with a single circular source trajectory is limited in terms of longitudinal scan coverage since extending the scan coverage beyond 40 mm results in significant cone-beam artifacts. A multiaxial CT acquisition is achieved by combining multiple sequential 3rd generation axial scans or by performing a single axial multisource CT scan with multiple longitudinally offset sources. Data from multiple axial scans or multiple sources provide complementary information. For full-scan acquisitions, we present a window-based 3D analytic cone-beam reconstruction algorithm by tessellating data from neighboring axial datasets. We also show that multi-axial CT acquisition can extend the axial scan coverage while minimizing cone-beam artifacts. For half-scan acquisitions, one cannot take advantage of conjugate rays. We propose a cone-angle dependent weighting approach to combine multi-axial half-scan data. We compute the relative contribution from each axial dataset to each voxel based on the X-ray beam collimation, the respective cone-angles, and the spacing between the axial scans. We present numerical experiments to demonstrate that the proposed techniques successfully reduce cone-beam artifacts at very large volumetric coverage.

  4. 2D image classification for 3D anatomy localization: employing deep convolutional neural networks

    Science.gov (United States)

    de Vos, Bob D.; Wolterink, Jelmer M.; de Jong, Pim A.; Viergever, Max A.; Išgum, Ivana

    2016-03-01

    Localization of anatomical regions of interest (ROIs) is a preprocessing step in many medical image analysis tasks. While trivial for humans, it is complex for automatic methods. Classic machine learning approaches require the challenge of hand crafting features to describe differences between ROIs and background. Deep convolutional neural networks (CNNs) alleviate this by automatically finding hierarchical feature representations from raw images. We employ this trait to detect anatomical ROIs in 2D image slices in order to localize them in 3D. In 100 low-dose non-contrast enhanced non-ECG synchronized screening chest CT scans, a reference standard was defined by manually delineating rectangular bounding boxes around three anatomical ROIs -- heart, aortic arch, and descending aorta. Every anatomical ROI was automatically identified using a combination of three CNNs, each analyzing one orthogonal image plane. While single CNNs predicted presence or absence of a specific ROI in the given plane, the combination of their results provided a 3D bounding box around it. Classification performance of each CNN, expressed in area under the receiver operating characteristic curve, was >=0.988. Additionally, the performance of ROI localization was evaluated. Median Dice scores for automatically determined bounding boxes around the heart, aortic arch, and descending aorta were 0.89, 0.70, and 0.85 respectively. The results demonstrate that accurate automatic 3D localization of anatomical structures by CNN-based 2D image classification is feasible.

  5. A comprehensive evaluation of the PRESAGE/optical-CT 3D dosimetry system

    Energy Technology Data Exchange (ETDEWEB)

    Sakhalkar, H. S.; Adamovics, J.; Ibbott, G.; Oldham, M. [Department of Radiation Oncology Physics, Duke University Medical Center, Durham, North Carolina 27710 (United States); Department of Chemistry and Biology, Rider University, Lawrenceville, New Jersey 08648 (United States); Department of Radiation Physics, M. D. Anderson Cancer Center, Houston, Texas 77030 (United States); Department of Radiation Oncology Physics, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2009-01-15

    This work presents extensive investigations to evaluate the robustness (intradosimeter consistency and temporal stability of response), reproducibility, precision, and accuracy of a relatively new 3D dosimetry system comprising a leuco-dye doped plastic 3D dosimeter (PRESAGE) and a commercial optical-CT scanner (OCTOPUS 5x scanner from MGS Research, Inc). Four identical PRESAGE 3D dosimeters were created such that they were compatible with the Radiologic Physics Center (RPC) head-and-neck (H and N) IMRT credentialing phantom. Each dosimeter was irradiated with a rotationally symmetric arrangement of nine identical small fields (1x3 cm{sup 2}) impinging on the flat circular face of the dosimeter. A repetitious sequence of three dose levels (4, 2.88, and 1.28 Gy) was delivered. The rotationally symmetric treatment resulted in a dose distribution with high spatial variation in axial planes but only gradual variation with depth along the long axis of the dosimeter. The significance of this treatment was that it facilitated accurate film dosimetry in the axial plane, for independent verification. Also, it enabled rigorous evaluation of robustness, reproducibility and accuracy of response, at the three dose levels. The OCTOPUS 5x commercial scanner was used for dose readout from the dosimeters at daily time intervals. The use of improved optics and acquisition technique yielded substantially improved noise characteristics (reduced to {approx}2%) than has been achieved previously. Intradosimeter uniformity of radiochromic response was evaluated by calculating a 3D gamma comparison between each dosimeter and axially rotated copies of the same dosimeter. This convenient technique exploits the rotational symmetry of the distribution. All points in the gamma comparison passed a 2% difference, 1 mm distance-to-agreement criteria indicating excellent intradosimeter uniformity even at low dose levels. Postirradiation, the dosimeters were all found to exhibit a slight increase in

  6. High Resolution 3D Radar Imaging of Comet Interiors

    Science.gov (United States)

    Asphaug, E. I.; Gim, Y.; Belton, M.; Brophy, J.; Weissman, P. R.; Heggy, E.

    2012-12-01

    Knowing the interiors of comets and other primitive bodies is fundamental to our understanding of how planets formed. We have developed a Discovery-class mission formulation, Comet Radar Explorer (CORE), based on the use of previously flown planetary radar sounding techniques, with the goal of obtaining high resolution 3D images of the interior of a small primitive body. We focus on the Jupiter-Family Comets (JFCs) as these are among the most primitive bodies reachable by spacecraft. Scattered in from far beyond Neptune, they are ultimate targets of a cryogenic sample return mission according to the Decadal Survey. Other suitable targets include primitive NEOs, Main Belt Comets, and Jupiter Trojans. The approach is optimal for small icy bodies ~3-20 km diameter with spin periods faster than about 12 hours, since (a) navigation is relatively easy, (b) radar penetration is global for decameter wavelengths, and (c) repeated overlapping ground tracks are obtained. The science mission can be as short as ~1 month for a fast-rotating JFC. Bodies smaller than ~1 km can be globally imaged, but the navigation solutions are less accurate and the relative resolution is coarse. Larger comets are more interesting, but radar signal is unlikely to be reflected from depths greater than ~10 km. So, JFCs are excellent targets for a variety of reasons. We furthermore focus on the use of Solar Electric Propulsion (SEP) to rendezvous shortly after the comet's perihelion. This approach leaves us with ample power for science operations under dormant conditions beyond ~2-3 AU. This leads to a natural mission approach of distant observation, followed by closer inspection, terminated by a dedicated radar mapping orbit. Radar reflections are obtained from a polar orbit about the icy nucleus, which spins underneath. Echoes are obtained from a sounder operating at dual frequencies 5 and 15 MHz, with 1 and 10 MHz bandwidths respectively. The dense network of echoes is used to obtain global 3D

  7. 2D-3D shape reconstruction of the distal femur from stereo X-Ray imaging using statistical shape models

    DEFF Research Database (Denmark)

    Baka, N.; Kaptein, B. L.; de Bruijne, Marleen;

    2011-01-01

    as it lowers both the acquisition costs and the radiation dose compared to CT. We propose a method for pose estimation and shape reconstruction of 3D bone surfaces from two (or more) calibrated X-ray images using a statistical shape model (SSM). User interaction is limited to manual initialization of the mean...... shape. The proposed method combines a 3D distance based objective function with automatic edge selection on a Canny edge map. Landmark-edge correspondences are weighted based on the orientation difference of the projected silhouette and the corresponding image edge. The method was evaluated by rigid...... pose estimation of ground truth shapes as well as 3D shape estimation using a SSM of the whole femur, from stereo cadaver X-rays, in vivo biplane fluoroscopy image-pairs, and an in vivo biplane fluoroscopic sequence. Ground truth shapes for all experiments were available in the form of CT segmentations...

  8. Fast CT-CT fluoroscopy registration with respiratory motion compensation for image-guided lung intervention

    Science.gov (United States)

    Su, Po; Xue, Zhong; Lu, Kongkuo; Yang, Jianhua; Wong, Stephen T.

    2012-02-01

    CT-fluoroscopy (CTF) is an efficient imaging method for guiding percutaneous lung interventions such as biopsy. During CTF-guided biopsy procedure, four to ten axial sectional images are captured in a very short time period to provide nearly real-time feedback to physicians, so that they can adjust the needle as it is advanced toward the target lesion. Although popularly used in clinics, this traditional CTF-guided intervention procedure may require frequent scans and cause unnecessary radiation exposure to clinicians and patients. In addition, CTF only generates limited slices of images and provides limited anatomical information. It also has limited response to respiratory movements and has narrow local anatomical dynamics. To better utilize CTF guidance, we propose a fast CT-CTF registration algorithm with respiratory motion estimation for image-guided lung intervention using electromagnetic (EM) guidance. With the pre-procedural exhale and inhale CT scans, it would be possible to estimate a series of CT images of the same patient at different respiratory phases. Then, once a CTF image is captured during the intervention, our algorithm can pick the best respiratory phase-matched 3D CT image and performs a fast deformable registration to warp the 3D CT toward the CTF. The new 3D CT image can be used to guide the intervention by superimposing the EM-guided needle location on it. Compared to the traditional repetitive CTF guidance, the registered CT integrates both 3D volumetric patient data and nearly real-time local anatomy for more effective and efficient guidance. In this new system, CTF is used as a nearly real-time sensor to overcome the discrepancies between static pre-procedural CT and the patient's anatomy, so as to provide global guidance that may be supplemented with electromagnetic (EM) tracking and to reduce the number of CTF scans needed. In the experiments, the comparative results showed that our fast CT-CTF algorithm can achieve better registration

  9. Submucosal Hemangioma of the Trachea in an Infant: Diagnosis and Follow-Up with 3D-CT/Bronchoscopy

    Directory of Open Access Journals (Sweden)

    Jungwha Choi

    2016-01-01

    Full Text Available Introduction: Infantile hemangiomas of the airway are diagnosed at bronchoscopy as part of the investigation of stridor or other respiratory symptoms. Here, we present three-dimensional computed tomography (3D-CT/bronchoscopy findings of submucosal subglottic hemangioma missed at bronchoscopy. Case Presentation: We report on the clinical usefulness of 3D-CT/bronchoscopy as the primary diagnostic tool and follow-up method in the evaluation of suspected airway infantile hemangiomas, especially when the hemangioma is the submucosal type. Conclusions: 3D-CT/bronchoscopy will reduce the need for invasive laryngoscopic studies and help to diagnose submucosal hemangiomas undetected on laryngoscope. Additionally, 3D-CT/bronchoscopy will help evaluating the extent of the lesion, degree of airway narrowing, and treatment response.

  10. Acceleration of EM-Based 3D CT Reconstruction Using FPGA.

    Science.gov (United States)

    Choi, Young-Kyu; Cong, Jason

    2016-06-01

    Reducing radiation doses is one of the key concerns in computed tomography (CT) based 3D reconstruction. Although iterative methods such as the expectation maximization (EM) algorithm can be used to address this issue, applying this algorithm to practice is difficult due to the long execution time. Our goal is to decrease this long execution time to an order of a few minutes, so that low-dose 3D reconstruction can be performed even in time-critical events. In this paper we introduce a novel parallel scheme that takes advantage of numerous block RAMs on field-programmable gate arrays (FPGAs). Also, an external memory bandwidth reduction strategy is presented to reuse both the sinogram and the voxel intensity. Moreover, a customized processing engine based on the FPGA is presented to increase overall throughput while reducing the logic consumption. Finally, a hardware and software flow is proposed to quickly construct a design for various CT machines. The complete reconstruction system is implemented on an FPGA-based server-class node. Experiments on actual patient data show that a 26.9 × speedup can be achieved over a 16-thread multicore CPU implementation.

  11. Submucosal Hemangioma of the Trachea in an Infant: Diagnosis and Follow-Up with 3D-CT/Bronchoscopy

    OpenAIRE

    Jungwha Choi; Soo Ah Im; Jee Young Kim

    2016-01-01

    Introduction: Infantile hemangiomas of the airway are diagnosed at bronchoscopy as part of the investigation of stridor or other respiratory symptoms. Here, we present three-dimensional computed tomography (3D-CT)/bronchoscopy findings of submucosal subglottic hemangioma missed at bronchoscopy. Case Presentation: We report on the clinical usefulness of 3D-CT/bronchoscopy as the primary diagnostic tool and follow-up method in the e...

  12. Intensity-based image registration for 3D spatial compounding using a freehand 3D ultrasound system

    Science.gov (United States)

    Pagoulatos, Niko; Haynor, David R.; Kim, Yongmin

    2002-04-01

    3D spatial compounding involves the combination of two or more 3D ultrasound (US) data sets, acquired under different insonation angles and windows, to form a higher quality 3D US data set. An important requirement for this method to succeed is the accurate registration between the US images used to form the final compounded image. We have developed a new automatic method for rigid and deformable registration of 3D US data sets, acquired using a freehand 3D US system. Deformation is provided by using a 3D thin-plate spline (TPS). Our method is fundamentally different from the previous ones in that the acquired scattered US 2D slices are registered and compounded directly into the 3D US volume. Our approach has several benefits over the traditional registration and spatial compounding methods: (i) we only peform one 3D US reconstruction, for the first acquired data set, therefore we save the computation time required to reconstruct subsequent acquired scans, (ii) for our registration we use (except for the first scan) the acquired high-resolution 2D US images rather than the 3D US reconstruction data which are of lower quality due to the interpolation and potential subsampling associated with 3D reconstruction, and (iii) the scans performed after the first one are not required to follow the typical 3D US scanning protocol, where a large number of dense slices have to be acquired; slices can be acquired in any fashion in areas where compounding is desired. We show that by taking advantage of the similar information contained in adjacent acquired 2D US slices, we can reduce the computation time of linear and nonlinear registrations by a factor of more than 7:1, without compromising registration accuracy. Furthermore, we implemented an adaptive approximation to the 3D TPS with local bilinear transformations allowing additional reduction of the nonlinear registration computation time by a factor of approximately 3.5. Our results are based on a commercially available

  13. Research of Fast 3D Imaging Based on Multiple Mode

    Science.gov (United States)

    Chen, Shibing; Yan, Huimin; Ni, Xuxiang; Zhang, Xiuda; Wang, Yu

    2016-02-01

    Three-dimensional (3D) imaging has received increasingly extensive attention and has been widely used currently. Lots of efforts have been put on three-dimensional imaging method and system study, in order to meet fast and high accurate requirement. In this article, we realize a fast and high quality stereo matching algorithm on field programmable gate array (FPGA) using the combination of time-of-flight (TOF) camera and binocular camera. Images captured from the two cameras own a same spatial resolution, letting us use the depth maps taken by the TOF camera to figure initial disparity. Under the constraint of the depth map as the stereo pairs when comes to stereo matching, expected disparity of each pixel is limited within a narrow search range. In the meanwhile, using field programmable gate array (FPGA, altera cyclone IV series) concurrent computing we can configure multi core image matching system, thus doing stereo matching on embedded system. The simulation results demonstrate that it can speed up the process of stereo matching and increase matching reliability and stability, realize embedded calculation, expand application range.

  14. 3-D Image Analysis of Fluorescent Drug Binding

    Directory of Open Access Journals (Sweden)

    M. Raquel Miquel

    2005-01-01

    Full Text Available Fluorescent ligands provide the means of studying receptors in whole tissues using confocal laser scanning microscopy and have advantages over antibody- or non-fluorescence-based method. Confocal microscopy provides large volumes of images to be measured. Histogram analysis of 3-D image volumes is proposed as a method of graphically displaying large amounts of volumetric image data to be quickly analyzed and compared. The fluorescent ligand BODIPY FL-prazosin (QAPB was used in mouse aorta. Histogram analysis reports the amount of ligand-receptor binding under different conditions and the technique is sensitive enough to detect changes in receptor availability after antagonist incubation or genetic manipulations. QAPB binding was concentration dependent, causing concentration-related rightward shifts in the histogram. In the presence of 10 μM phenoxybenzamine (blocking agent, the QAPB (50 nM histogram overlaps the autofluorescence curve. The histogram obtained for the 1D knockout aorta lay to the left of that of control and 1B knockout aorta, indicating a reduction in 1D receptors. We have shown, for the first time, that it is possible to graphically display binding of a fluorescent drug to a biological tissue. Although our application is specific to adrenergic receptors, the general method could be applied to any volumetric, fluorescence-image-based assay.

  15. 3D imaging and wavefront sensing with a plenoptic objective

    Science.gov (United States)

    Rodríguez-Ramos, J. M.; Lüke, J. P.; López, R.; Marichal-Hernández, J. G.; Montilla, I.; Trujillo-Sevilla, J.; Femenía, B.; Puga, M.; López, M.; Fernández-Valdivia, J. J.; Rosa, F.; Dominguez-Conde, C.; Sanluis, J. C.; Rodríguez-Ramos, L. F.

    2011-06-01

    Plenoptic cameras have been developed over the last years as a passive method for 3d scanning. Several superresolution algorithms have been proposed in order to increase the resolution decrease associated with lightfield acquisition with a microlenses array. A number of multiview stereo algorithms have also been applied in order to extract depth information from plenoptic frames. Real time systems have been implemented using specialized hardware as Graphical Processing Units (GPUs) and Field Programmable Gates Arrays (FPGAs). In this paper, we will present our own implementations related with the aforementioned aspects but also two new developments consisting of a portable plenoptic objective to transform every conventional 2d camera in a 3D CAFADIS plenoptic camera, and the novel use of a plenoptic camera as a wavefront phase sensor for adaptive optics (OA). The terrestrial atmosphere degrades the telescope images due to the diffraction index changes associated with the turbulence. These changes require a high speed processing that justify the use of GPUs and FPGAs. Na artificial Laser Guide Stars (Na-LGS, 90km high) must be used to obtain the reference wavefront phase and the Optical Transfer Function of the system, but they are affected by defocus because of the finite distance to the telescope. Using the telescope as a plenoptic camera allows us to correct the defocus and to recover the wavefront phase tomographically. These advances significantly increase the versatility of the plenoptic camera, and provides a new contribution to relate the wave optics and computer vision fields, as many authors claim.

  16. Myocardial strains from 3D displacement encoded magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Kindberg Katarina

    2012-04-01

    Full Text Available Abstract Background The ability to measure and quantify myocardial motion and deformation provides a useful tool to assist in the diagnosis, prognosis and management of heart disease. The recent development of magnetic resonance imaging methods, such as harmonic phase analysis of tagging and displacement encoding with stimulated echoes (DENSE, make detailed non-invasive 3D kinematic analyses of human myocardium possible in the clinic and for research purposes. A robust analysis method is required, however. Methods We propose to estimate strain using a polynomial function which produces local models of the displacement field obtained with DENSE. Given a specific polynomial order, the model is obtained as the least squares fit of the acquired displacement field. These local models are subsequently used to produce estimates of the full strain tensor. Results The proposed method is evaluated on a numerical phantom as well as in vivo on a healthy human heart. The evaluation showed that the proposed method produced accurate results and showed low sensitivity to noise in the numerical phantom. The method was also demonstrated in vivo by assessment of the full strain tensor and to resolve transmural strain variations. Conclusions Strain estimation within a 3D myocardial volume based on polynomial functions yields accurate and robust results when validated on an analytical model. The polynomial field is capable of resolving the measured material positions from the in vivo data, and the obtained in vivo strains values agree with previously reported myocardial strains in normal human hearts.

  17. Dynamic CT myocardial perfusion imaging.

    Science.gov (United States)

    Caruso, Damiano; Eid, Marwen; Schoepf, U Joseph; Jin, Kwang Nam; Varga-Szemes, Akos; Tesche, Christian; Mangold, Stefanie; Spandorfer, Adam; Laghi, Andrea; De Cecco, Carlo N

    2016-10-01

    Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

  18. 3D imaging of semiconductor components by discrete laminography

    Energy Technology Data Exchange (ETDEWEB)

    Batenburg, K. J. [Centrum Wiskunde and Informatica, P.O. Box 94079, NL-1090 GB Amsterdam, The Netherlands and iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk (Belgium); Palenstijn, W. J.; Sijbers, J. [iMinds-Vision Lab, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk (Belgium)

    2014-06-19

    X-ray laminography is a powerful technique for quality control of semiconductor components. Despite the advantages of nondestructive 3D imaging over 2D techniques based on sectioning, the acquisition time is still a major obstacle for practical use of the technique. In this paper, we consider the application of Discrete Tomography to laminography data, which can potentially reduce the scanning time while still maintaining a high reconstruction quality. By incorporating prior knowledge in the reconstruction algorithm about the materials present in the scanned object, far more accurate reconstructions can be obtained from the same measured data compared to classical reconstruction methods. We present a series of simulation experiments that illustrate the potential of the approach.

  19. Unsupervised fuzzy segmentation of 3D magnetic resonance brain images

    Science.gov (United States)

    Velthuizen, Robert P.; Hall, Lawrence O.; Clarke, Laurence P.; Bensaid, Amine M.; Arrington, J. A.; Silbiger, Martin L.

    1993-07-01

    Unsupervised fuzzy methods are proposed for segmentation of 3D Magnetic Resonance images of the brain. Fuzzy c-means (FCM) has shown promising results for segmentation of single slices. FCM has been investigated for volume segmentations, both by combining results of single slices and by segmenting the full volume. Different strategies and initializations have been tried. In particular, two approaches have been used: (1) a method by which, iteratively, the furthest sample is split off to form a new cluster center, and (2) the traditional FCM in which the membership grade matrix is initialized in some way. Results have been compared with volume segmentations by k-means and with two supervised methods, k-nearest neighbors and region growing. Results of individual segmentations are presented as well as comparisons on the application of the different methods to a number of tumor patient data sets.

  20. Usefulness of three-dimensional CT pancreatography (3D-CTP) after the balloon-ERP for pancreatic diseases

    Energy Technology Data Exchange (ETDEWEB)

    Ueki, Toshiharu; Oishi, Yayoi; Sakaguchi, Seigo; Sakurai, Toshihiro; Yao, Tsuneyoshi [Fukuoka Univ., Chikushino (Japan). Chikushi Hospital; Ichimaru, Yoshihiko; Koga, Yuki; Ikeda, Seiyo

    1998-03-01

    The clinical usefulness of 3D-CTP combined with the balloon-ERP and helical-CT was discussed. Authors diagnosed 42 patients with pancreatic diseases, including 5 of pancreatic carcinoma, 3 of serous cystadenoma, 6 of muciparous pancreatic cyst, 28 of chronic pancreatitis (including 8 cases of complicated pseudocyst). The images could reconstruct three-dimensionally the tapering constriction in the main pancreatic duct for all 5 cases of pancreatic carcinoma, the exclusion in the main pancreatic duct for 3 cases of serous cystadenoma and 1 case of muciparous pancreatic cyst, the parietal irregularity for 14 cases and the smooth constriction for 9 cases in main pancreatic duct of chronic pancreatitis, the morphology of the cyst and the spatial relationship between the cyst and the pancreatic duct in 5 of 6 cases of muciparous pancreatic cyst and 7 of 8 cases of complicated pseudocyst. Furthermore, the 3D-CTP could demonstrate the branched pancreatic duct at the constriction site which was not detected by the balloon-ERP in 2 cases of chronic pancreatitis with the constriction at the main pancreatic duct, and the joining manner of cyst to the pancreatic duct which was indistinct by the balloon-ERP in 6 cases of pancreatic cyst. These results show that 3D-CTP is useful for the qualitative diagnosis and applicable for the understanding of pancreatic diseases and for the simulation of surgery. (K.H.)

  1. Extraction and classification of 3D objects from volumetric CT data

    Science.gov (United States)

    Song, Samuel M.; Kwon, Junghyun; Ely, Austin; Enyeart, John; Johnson, Chad; Lee, Jongkyu; Kim, Namho; Boyd, Douglas P.

    2016-05-01

    We propose an Automatic Threat Detection (ATD) algorithm for Explosive Detection System (EDS) using our multistage Segmentation Carving (SC) followed by Support Vector Machine (SVM) classifier. The multi-stage Segmentation and Carving (SC) step extracts all suspect 3-D objects. The feature vector is then constructed for all extracted objects and the feature vector is classified by the Support Vector Machine (SVM) previously learned using a set of ground truth threat and benign objects. The learned SVM classifier has shown to be effective in classification of different types of threat materials. The proposed ATD algorithm robustly deals with CT data that are prone to artifacts due to scatter, beam hardening as well as other systematic idiosyncrasies of the CT data. Furthermore, the proposed ATD algorithm is amenable for including newly emerging threat materials as well as for accommodating data from newly developing sensor technologies. Efficacy of the proposed ATD algorithm with the SVM classifier is demonstrated by the Receiver Operating Characteristics (ROC) curve that relates Probability of Detection (PD) as a function of Probability of False Alarm (PFA). The tests performed using CT data of passenger bags shows excellent performance characteristics.

  2. Spectral ladar: towards active 3D multispectral imaging

    Science.gov (United States)

    Powers, Michael A.; Davis, Christopher C.

    2010-04-01

    In this paper we present our Spectral LADAR concept, an augmented implementation of traditional LADAR. This sensor uses a polychromatic source to obtain range-resolved 3D spectral images which are used to identify objects based on combined spatial and spectral features, resolving positions in three dimensions and up to hundreds of meters in distance. We report on a proof-of-concept Spectral LADAR demonstrator that generates spectral point clouds from static scenes. The demonstrator transmits nanosecond supercontinuum pulses generated in a photonic crystal fiber. Currently we use a rapidly tuned receiver with a high-speed InGaAs APD for 25 spectral bands with the future expectation of implementing a linear APD array spectrograph. Each spectral band is independently range resolved with multiple return pulse recognition. This is a critical feature, enabling simultaneous spectral and spatial unmixing of partially obscured objects when not achievable using image fusion of monochromatic LADAR and passive spectral imagers. This enables higher identification confidence in highly cluttered environments such as forested or urban areas (e.g. vehicles behind camouflage or foliage). These environments present challenges for situational awareness and robotic perception which can benefit from the unique attributes of Spectral LADAR. Results from this demonstrator unit are presented for scenes typical of military operations and characterize the operation of the device. The results are discussed here in the context of autonomous vehicle navigation and target recognition.

  3. GPU-accelerated denoising of 3D magnetic resonance images

    Energy Technology Data Exchange (ETDEWEB)

    Howison, Mark; Wes Bethel, E.

    2014-05-29

    The raw computational power of GPU accelerators enables fast denoising of 3D MR images using bilateral filtering, anisotropic diffusion, and non-local means. In practice, applying these filtering operations requires setting multiple parameters. This study was designed to provide better guidance to practitioners for choosing the most appropriate parameters by answering two questions: what parameters yield the best denoising results in practice? And what tuning is necessary to achieve optimal performance on a modern GPU? To answer the first question, we use two different metrics, mean squared error (MSE) and mean structural similarity (MSSIM), to compare denoising quality against a reference image. Surprisingly, the best improvement in structural similarity with the bilateral filter is achieved with a small stencil size that lies within the range of real-time execution on an NVIDIA Tesla M2050 GPU. Moreover, inappropriate choices for parameters, especially scaling parameters, can yield very poor denoising performance. To answer the second question, we perform an autotuning study to empirically determine optimal memory tiling on the GPU. The variation in these results suggests that such tuning is an essential step in achieving real-time performance. These results have important implications for the real-time application of denoising to MR images in clinical settings that require fast turn-around times.

  4. High resolution 3D imaging of synchrotron generated microbeams

    Energy Technology Data Exchange (ETDEWEB)

    Gagliardi, Frank M., E-mail: frank.gagliardi@wbrc.org.au [Alfred Health Radiation Oncology, The Alfred, Melbourne, Victoria 3004, Australia and School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia); Cornelius, Iwan [Imaging and Medical Beamline, Australian Synchrotron, Clayton, Victoria 3168, Australia and Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales 2500 (Australia); Blencowe, Anton [Division of Health Sciences, School of Pharmacy and Medical Sciences, The University of South Australia, Adelaide, South Australia 5000, Australia and Division of Information Technology, Engineering and the Environment, Mawson Institute, University of South Australia, Mawson Lakes, South Australia 5095 (Australia); Franich, Rick D. [School of Applied Sciences and Health Innovations Research Institute, RMIT University, Melbourne, Victoria 3000 (Australia); Geso, Moshi [School of Medical Sciences, RMIT University, Bundoora, Victoria 3083 (Australia)

    2015-12-15

    Purpose: Microbeam radiation therapy (MRT) techniques are under investigation at synchrotrons worldwide. Favourable outcomes from animal and cell culture studies have proven the efficacy of MRT. The aim of MRT researchers currently is to progress to human clinical trials in the near future. The purpose of this study was to demonstrate the high resolution and 3D imaging of synchrotron generated microbeams in PRESAGE® dosimeters using laser fluorescence confocal microscopy. Methods: Water equivalent PRESAGE® dosimeters were fabricated and irradiated with microbeams on the Imaging and Medical Beamline at the Australian Synchrotron. Microbeam arrays comprised of microbeams 25–50 μm wide with 200 or 400 μm peak-to-peak spacing were delivered as single, cross-fire, multidirectional, and interspersed arrays. Imaging of the dosimeters was performed using a NIKON A1 laser fluorescence confocal microscope. Results: The spatial fractionation of the MRT beams was clearly visible in 2D and up to 9 mm in depth. Individual microbeams were easily resolved with the full width at half maximum of microbeams measured on images with resolutions of as low as 0.09 μm/pixel. Profiles obtained demonstrated the change of the peak-to-valley dose ratio for interspersed MRT microbeam arrays and subtle variations in the sample positioning by the sample stage goniometer were measured. Conclusions: Laser fluorescence confocal microscopy of MRT irradiated PRESAGE® dosimeters has been validated in this study as a high resolution imaging tool for the independent spatial and geometrical verification of MRT beam delivery.

  5. CT and MRI assessment and characterization using segmentation and 3D modeling techniques: applications to muscle, bone and brain

    Directory of Open Access Journals (Sweden)

    Paolo Gargiulo

    2014-03-01

    Full Text Available This paper reviews the novel use of CT and MRI data and image processing tools to segment and reconstruct tissue images in 3D to determine characteristics of muscle, bone and brain.This to study and simulate the structural changes occurring in healthy and pathological conditions as well as in response to clinical treatments. Here we report the application of this methodology to evaluate and quantify: 1. progression of atrophy in human muscle subsequent to permanent lower motor neuron (LMN denervation, 2. muscle recovery as induced by functional electrical stimulation (FES, 3. bone quality in patients undergoing total hip replacement and 4. to model the electrical activity of the brain. Study 1: CT data and segmentation techniques were used to quantify changes in muscle density and composition by associating the Hounsfield unit values of muscle, adipose and fibrous connective tissue with different colors. This method was employed to monitor patients who have permanent muscle LMN denervation in the lower extremities under two different conditions: permanent LMN denervated not electrically stimulated and stimulated. Study 2: CT data and segmentation techniques were employed, however, in this work we assessed bone and muscle conditions in the pre-operative CT scans of patients scheduled to undergo total hip replacement. In this work, the overall anatomical structure, the bone mineral density (BMD and compactness of quadriceps muscles and proximal femoral was computed to provide a more complete view for surgeons when deciding which implant technology to use. Further, a Finite element analysis provided a map of the strains around the proximal femur socket when solicited by typical stresses caused by an implant press fitting. Study 3 describes a method to model the electrical behavior of human brain using segmented MR images. The aim of the work is to use these models to predict the electrical activity of the human brain under normal and pathological

  6. 3D Seismic Imaging over a Potential Collapse Structure

    Science.gov (United States)

    Gritto, Roland; O'Connell, Daniel; Elobaid Elnaiem, Ali; Mohamed, Fathelrahman; Sadooni, Fadhil

    2016-04-01

    The Middle-East has seen a recent boom in construction including the planning and development of complete new sub-sections of metropolitan areas. Before planning and construction can commence, however, the development areas need to be investigated to determine their suitability for the planned project. Subsurface parameters such as the type of material (soil/rock), thickness of top soil or rock layers, depth and elastic parameters of basement, for example, comprise important information needed before a decision concerning the suitability of the site for construction can be made. A similar problem arises in environmental impact studies, when subsurface parameters are needed to assess the geological heterogeneity of the subsurface. Environmental impact studies are typically required for each construction project, particularly for the scale of the aforementioned building boom in the Middle East. The current study was conducted in Qatar at the location of a future highway interchange to evaluate a suite of 3D seismic techniques in their effectiveness to interrogate the subsurface for the presence of karst-like collapse structures. The survey comprised an area of approximately 10,000 m2 and consisted of 550 source- and 192 receiver locations. The seismic source was an accelerated weight drop while the geophones consisted of 3-component 10 Hz velocity sensors. At present, we analyzed over 100,000 P-wave phase arrivals and performed high-resolution 3-D tomographic imaging of the shallow subsurface. Furthermore, dispersion analysis of recorded surface waves will be performed to obtain S-wave velocity profiles of the subsurface. Both results, in conjunction with density estimates, will be utilized to determine the elastic moduli of the subsurface rock layers.

  7. 4D CT amplitude binning for the generation of a time-averaged 3D mid-position CT scan.

    Science.gov (United States)

    Kruis, Matthijs F; van de Kamer, Jeroen B; Belderbos, José S A; Sonke, Jan-Jakob; van Herk, Marcel

    2014-09-21

    The purpose of this study was to develop a method to use amplitude binned 4D-CT (A-4D-CT) data for the construction of mid-position CT data and to compare the results with data created from phase-binned 4D-CT (P-4D-CT) data. For the latter purpose we have developed two measures which describe the regularity of the 4D data and we have tried to correlate these measures with the regularity of the external respiration signal. 4D-CT data was acquired for 27 patients on a combined PET-CT scanner. The 4D data were reconstructed twice, using phase and amplitude binning. The 4D frames of each dataset were registered using a quadrature-based optical flow method. After registration the deformation vector field was repositioned to the mid-position. Since amplitude-binned 4D data does not provide temporal information, we corrected the mid-position for the occupancy of the bins. We quantified the differences between the two mid-position datasets in terms of tumour offset and amplitude differences. Furthermore, we measured the standard deviation of the image intensity over the respiration after registration (σregistration) and the regularity of the deformation vector field (Delta J) to quantify the quality of the 4D-CT data. These measures were correlated to the regularity of the external respiration signal (σsignal).The two irregularity measures, Delta J and σregistration, were dependent on each other (p<0.0001, R2=0.80 for P-4D-CT, R2=0.74 for A-4D-CT). For all datasets amplitude binning resulted in lower Delta J and σregistration and large decreases led to visible quality improvements in the mid-position data. The quantity of artefact decrease was correlated to the irregularity of the external respiratory signal.The average tumour offset between the phase and amplitude binned mid-position without occupancy correction was 0.42 mm in the caudal direction (10.6% of the amplitude). After correction this was reduced to 0.16 mm in caudal direction (4.1% of the amplitude

  8. Enhanced 3D fluorescence live cell imaging on nanoplasmonic substrate

    Energy Technology Data Exchange (ETDEWEB)

    Gartia, Manas Ranjan [Department of Nuclear, Plasma and Radiological Engineering, University of Illinois, Urbana, IL 61801 (United States); Hsiao, Austin; Logan Liu, G [Department of Bioengineering, University of Illinois, Urbana, IL 61801 (United States); Sivaguru, Mayandi [Institute for Genomic Biology, University of Illinois, Urbana, IL 61801 (United States); Chen Yi, E-mail: loganliu@illinois.edu [Department of Electrical and Computer Engineering, University of Illinois, Urbana, IL 61801 (United States)

    2011-09-07

    We have created a randomly distributed nanocone substrate on silicon coated with silver for surface-plasmon-enhanced fluorescence detection and 3D cell imaging. Optical characterization of the nanocone substrate showed it can support several plasmonic modes (in the 300-800 nm wavelength range) that can be coupled to a fluorophore on the surface of the substrate, which gives rise to the enhanced fluorescence. Spectral analysis suggests that a nanocone substrate can create more excitons and shorter lifetime in the model fluorophore Rhodamine 6G (R6G) due to plasmon resonance energy transfer from the nanocone substrate to the nearby fluorophore. We observed three-dimensional fluorescence enhancement on our substrate shown from the confocal fluorescence imaging of chinese hamster ovary (CHO) cells grown on the substrate. The fluorescence intensity from the fluorophores bound on the cell membrane was amplified more than 100-fold as compared to that on a glass substrate. We believe that strong scattering within the nanostructured area coupled with random scattering inside the cell resulted in the observed three-dimensional enhancement in fluorescence with higher photostability on the substrate surface.

  9. Autostereoscopic 3D visualization and image processing system for neurosurgery.

    Science.gov (United States)

    Meyer, Tobias; Kuß, Julia; Uhlemann, Falk; Wagner, Stefan; Kirsch, Matthias; Sobottka, Stephan B; Steinmeier, Ralf; Schackert, Gabriele; Morgenstern, Ute

    2013-06-01

    A demonstrator system for planning neurosurgical procedures was developed based on commercial hardware and software. The system combines an easy-to-use environment for surgical planning with high-end visualization and the opportunity to analyze data sets for research purposes. The demonstrator system is based on the software AMIRA. Specific algorithms for segmentation, elastic registration, and visualization have been implemented and adapted to the clinical workflow. Modules from AMIRA and the image processing library Insight Segmentation and Registration Toolkit (ITK) can be combined to solve various image processing tasks. Customized modules tailored to specific clinical problems can easily be implemented using the AMIRA application programming interface and a self-developed framework for ITK filters. Visualization is done via autostereoscopic displays, which provide a 3D impression without viewing aids. A Spaceball device allows a comfortable, intuitive way of navigation in the data sets. Via an interface to a neurosurgical navigation system, the demonstrator system can be used intraoperatively. The precision, applicability, and benefit of the demonstrator system for planning of neurosurgical interventions and for neurosurgical research were successfully evaluated by neurosurgeons using phantom and patient data sets.

  10. Multiframe image point matching and 3-d surface reconstruction.

    Science.gov (United States)

    Tsai, R Y

    1983-02-01

    This paper presents two new methods, the Joint Moment Method (JMM) and the Window Variance Method (WVM), for image matching and 3-D object surface reconstruction using multiple perspective views. The viewing positions and orientations for these perspective views are known a priori, as is usually the case for such applications as robotics and industrial vision as well as close range photogrammetry. Like the conventional two-frame correlation method, the JMM and WVM require finding the extrema of 1-D curves, which are proved to theoretically approach a delta function exponentially as the number of frames increases for the JMM and are much sharper than the two-frame correlation function for both the JMM and the WVM, even when the image point to be matched cannot be easily distinguished from some of the other points. The theoretical findings have been supported by simulations. It is also proved that JMM and WVM are not sensitive to certain radiometric effects. If the same window size is used, the computational complexity for the proposed methods is about n - 1 times that for the two-frame method where n is the number of frames. Simulation results show that the JMM and WVM require smaller windows than the two-frame correlation method with better accuracy, and therefore may even be more computationally feasible than the latter since the computational complexity increases quadratically as a function of the window size.

  11. Age estimation by 3D CT-scans of the Borremose Woman, a Danish bog body

    DEFF Research Database (Denmark)

    Villa, Chiara; Møller Rasmussen, Maria; Lynnerup, Niels

    2011-01-01

    been visualized from CT-scans using the Mimics software from Materialise. Extensive manual editing was necessary, as is common with bog bodies, since the bones were severely degraded and the ordinary range of Hounsfield Units (HU), used for clinical work, is not suitable. Only the cranium, the left...... ribs and the right auricular surface were 3D visualized. Based on these visualizations, the age was estimated by applying macroscopic methods routinely used for skeletal remains: the cranial sutures closure (Meindl & Lovejoy 1985), the sternal rib end (Iscan & Loth 1986) and the auricular surface...... was 16 to 24 years. Many problems had to be addressed. First of all, the degradation of the skeletal tissue does not allow a complete visualization: the bones are demineralized because of the acidic bog environment. Another problem is the subjectivity that can arise during manual editing, especially...

  12. Computed Tomography 3-D Imaging of the Metal Deformation Flow Path in Friction Stir Welding

    Science.gov (United States)

    Schneider, Judy; Beshears, Ronald; Nunes, Arthur C., Jr.

    2005-01-01

    In friction stir welding (FSW), a rotating threaded pin tool is inserted into a weld seam and literally stirs the edges of the seam together. To determine optimal processing parameters for producing a defect free weld, a better understanding of the resulting metal deformation flow path is required. Marker studies are the principal method of studying the metal deformation flow path around the FSW pin tool. In our study, we have used computed tomography (CT) scans to reveal the flow pattern of a lead wire embedded in a FSW weld seam. At the welding temperature of aluminum, the lead becomes molten and is carried with the macro-flow of the weld metal. By using CT images, a 3-dimensional (3D) image of the lead flow pattern can be reconstructed. CT imaging was found to be a convenient and comprehensive way of collecting and displaying tracer data. It marks an advance over previous more tedious and ambiguous radiographic/metallographic data collection methods.

  13. CT三维最小类内散度多分类支持向量机在肺结节识别中的应用%Application of CT images based 3D minimum within-class scatter multi-class support vector machine in the identification of lung nodules

    Institute of Scientific and Technical Information of China (English)

    范小波; 董莹; 王义云

    2015-01-01

    Objective To analyze the value of CT images based 3D minimum within‐class scatter multi‐class support vector machine (MC‐SVM ) in the identification of lung nodules .Methods During Jan .2012 and Jan .2014 ,a total of 50 cases with pulmonary sarcoidosis were enrolled .Lung CT based 3D matrix pattern volume of interest (VOI) structure were divided into nodules samples and non‐nodule samples .Region of interest (ROI) was extracted by using automatic extraction algorithm ,which was further divided into nodules and non‐nodular ROI .Then the rec‐ognition accuracy ,true positive rate and false positive rate of large‐scale massive training artificial neural network (M TANN) ,fuzzy ′one on one′ multi‐class SVM (matFLSSVM ) ,3D matrix model MC‐SVM and 3D minimum with‐in‐class scatter MC‐SVM were compared by using receiver operating curve (ROC) .Results 3D minimum within‐class scatter MC‐SVM was with the highest recognition accuracy and true positive rate ,and the lowest false positive rate ,compared with the other algorithms (P< 0 .05) .Conclusion 3D minimum within‐class scatter MC‐SVM might be accurate for the recognition if long nodules .%目的:分析 CT 三维最小类内散度多分类支持向量机(MC‐SVM )对肺结节的识别能力及优点。方法选择2012年1月至2014年1月确诊的肺结节病患者50例,根据基于三维矩阵模式的感兴趣体(VOI)的构成,分为结节样和非结节样;采用自动提取算法提取感兴趣区(ROI),分为结节 ROI 和非结节 ROI ;采用受试者工作特征(ROC)曲线比较大规模训练人工神经网络(M TANN)、基于矩阵模式的模糊最小二乘 SVM (matFLSSVM )、三维矩阵模式 MC‐SVM 和三维最小类内散度 MC‐SVM 的识别精度,同时比较各种方法在不同截断点时的真阳性率和假阳性率。结果三维最小类内散度 MC‐SVM 的识别精度、真阳性率均高于其他算法,而假阳

  14. In Situ Casting and Imaging of the Rat Airway Tree for Accurate 3D Reconstruction

    Science.gov (United States)

    Jacob, Richard E.; Colby, Sean M.; Kabilan, Senthil; Einstein, Daniel R.; Carson, James P.

    2014-01-01

    The use of anatomically accurate, animal-specific airway geometries is important for understanding and modeling the physiology of the respiratory system. One approach for acquiring detailed airway architecture is to create a bronchial cast of the conducting airways. However, typical casting procedures either do not faithfully preserve the in vivo branching angles or produce rigid casts that when removed for imaging are fragile and thus easily damaged. We address these problems by creating an in situ bronchial cast of the conducting airways in rats that can be subsequently imaged in situ using 3D micro-CT imaging. We also demonstrate that deformations in airway branch angles resulting from the casting procedure are small, and that these angle deformations can be reversed through an interactive adjustment of the segmented cast geometry. Animal work was approved by the Institutional Animal Care and Use Committee of Pacific Northwest National Laboratory. PMID:23786464

  15. Ultrasonography Fused with PET-CT Hybrid Imaging

    DEFF Research Database (Denmark)

    Udesen, Jesper; Ewertsen, Caroline; Gran, Fredrik

    2011-01-01

    We present a method with fusion of images of three modalities 18F-FDG PET, CT, and 3-D ultrasound (US) applied to imaging of the anal canal and the rectum. To obtain comparable geometries in the three imaging modalities, a plexiglas rod, with the same dimensions as the US transducer, is placed...... in the anal canal prior to the PET-CT examination. The method is based on manual co-registration of PET-CT images and 3-D US images. The three-modality imaging of the rectum-anal canal may become useful as a supplement to conventional imaging in the external radiation therapy in the treatment of anal cancer......, where the precise delineation of a tumor is crucial to avoid damage from radiation therapy to the healthy tissue surrounding it. The technique is still in a phase of development, and the demands for integration different company software systems are significant before commercial application. Three...

  16. Contributions in compression of 3D medical images and 2D images; Contributions en compression d'images medicales 3D et d'images naturelles 2D

    Energy Technology Data Exchange (ETDEWEB)

    Gaudeau, Y

    2006-12-15

    The huge amounts of volumetric data generated by current medical imaging techniques in the context of an increasing demand for long term archiving solutions, as well as the rapid development of distant radiology make the use of compression inevitable. Indeed, if the medical community has sided until now with compression without losses, most of applications suffer from compression ratios which are too low with this kind of compression. In this context, compression with acceptable losses could be the most appropriate answer. So, we propose a new loss coding scheme based on 3D (3 dimensional) Wavelet Transform and Dead Zone Lattice Vector Quantization 3D (DZLVQ) for medical images. Our algorithm has been evaluated on several computerized tomography (CT) and magnetic resonance image volumes. The main contribution of this work is the design of a multidimensional dead zone which enables to take into account correlations between neighbouring elementary volumes. At high compression ratios, we show that it can out-perform visually and numerically the best existing methods. These promising results are confirmed on head CT by two medical patricians. The second contribution of this document assesses the effect with-loss image compression on CAD (Computer-Aided Decision) detection performance of solid lung nodules. This work on 120 significant lungs images shows that detection did not suffer until 48:1 compression and still was robust at 96:1. The last contribution consists in the complexity reduction of our compression scheme. The first allocation dedicated to 2D DZLVQ uses an exponential of the rate-distortion (R-D) functions. The second allocation for 2D and 3D medical images is based on block statistical model to estimate the R-D curves. These R-D models are based on the joint distribution of wavelet vectors using a multidimensional mixture of generalized Gaussian (MMGG) densities. (author)

  17. 2D/3D registration system based on single X-ray image and CT data%基于单幅X线图像和CT数据的2D/3D配准系统

    Institute of Scientific and Technical Information of China (English)

    焦培峰; 秦安; 赵卫东; 欧阳钧; 张美超; 樊继宏; 钟世镇; 李鉴轶

    2010-01-01

    目的 建立基于统一计算架构(CUDA)下以单幅x线图像及CT扫描数据为数据源的2D/3D配准系统,并应用于膝关节在体运动及植入假体稳定性研究.方法首先应用张正友标定法对采集X线图像设备进行标定;其次基于CUDA构架利用光线跟踪算法生成数字影像重建图像,以相关性函数为相似性测度计算2D/3D配准参数;最后以三维激光扫描仪所获得的点云数据进行3D/3D配准,以验证2D/3D配准结果.结果 以标本整体位置变换进行配准实验,6自由度平均误差中,位移小于1 mm,旋转小于1°.结论 此2D/3D配准系统达到了运动检测精度的要求,可以作为研究膝关节运动情况和假体在体稳定性研究的计算平台.

  18. 3D mapping from high resolution satellite images

    Science.gov (United States)

    Goulas, D.; Georgopoulos, A.; Sarakenos, A.; Paraschou, Ch.

    2013-08-01

    In recent years 3D information has become more easily available. Users' needs are constantly increasing, adapting to this reality and 3D maps are in more demand. 3D models of the terrain in CAD or other environments have already been common practice; however one is bound by the computer screen. This is why contemporary digital methods have been developed in order to produce portable and, hence, handier 3D maps of various forms. This paper deals with the implementation of the necessary procedures to produce holographic 3D maps and three dimensionally printed maps. The main objective is the production of three dimensional maps from high resolution aerial and/or satellite imagery with the use of holography and but also 3D printing methods. As study area the island of Antiparos was chosen, as there were readily available suitable data. These data were two stereo pairs of Geoeye-1 and a high resolution DTM of the island. Firstly the theoretical bases of holography and 3D printing are described, and the two methods are analyzed and there implementation is explained. In practice a x-axis parallax holographic map of the Antiparos Island is created and a full parallax (x-axis and y-axis) holographic map is created and printed, using the holographic method. Moreover a three dimensional printed map of the study area has been created using 3dp (3d printing) method. The results are evaluated for their usefulness and efficiency.

  19. Fast, high-resolution 3D dosimetry utilizing a novel optical-CT scanner incorporating tertiary telecentric collimation.

    Science.gov (United States)

    Sakhalkar, H S; Oldham, M

    2008-01-01

    This study introduces a charge coupled device (CCD) area detector based optical-computed tomography (optical-CT) scanner for comprehensive verification of radiation dose distributions recorded in nonscattering radiochromic dosimeters. Defining characteristics include: (i) a very fast scanning time of approximately 5 min to acquire a complete three-dimensional (3D) dataset, (ii) improved image formation through the use of custom telecentric optics, which ensures accurate projection images and minimizes artifacts from scattered and stray-light sources, and (iii) high resolution (potentially 50 microm) isotropic 3D dose readout. The performance of the CCD scanner for 3D dose readout was evaluated by comparison with independent 3D readout from the single laser beam OCTOPUS-scanner for the same PRESAGE dosimeters. The OCTOPUS scanner was considered the "gold standard" technique in light of prior studies demonstrating its accuracy. Additional comparisons were made against calculated dose distributions from the ECLIPSE treatment-planning system. Dose readout for the following treatments were investigated: (i) a single rectangular beam irradiation to investigate small field and very steep dose gradient dosimetry away from edge effects, (ii) a 2-field open beam parallel-opposed irradiation to investigate dosimetry along steep dose gradients, and (iii) a 7-field intensity modulated radiation therapy (IMRT) irradiation to investigate dosimetry for complex treatment delivery involving modulation of fluence and for dosimetry along moderate dose gradients. Dose profiles, dose-difference plots, and gamma maps were employed to evaluate quantitative estimates of agreement between independently measured and calculated dose distributions. Results indicated that dose readout from the CCD scanner was in agreement with independent gold-standard readout from the OCTOPUS-scanner as well as the calculated ECLIPSE dose distribution for all treatments, except in regions within a few

  20. Edge detection of industrial CT 3D image based on wavelet locating and Facet model%基于小波定位及Facet模型的三维工业CT图像边缘检测

    Institute of Scientific and Technical Information of China (English)

    曾理; 郭海燕; 马睿

    2010-01-01

    进行三维图像边缘检测时,利用Facet模型能够获得较精确的边缘信息,但耗时较多;而利用小波变换可获得较快的检测速度,但得到的边缘依赖于阈值的大小.综合上述两种方法的特点,提出了一种基于小波定位及Facet模型的三维边缘检测方法.首先,对工业CT 三维图像进行三维小波变换,设定较小阈值,得到三维粗边缘,即对图像边缘进行粗定位;然后,针对粗边缘点逐个进行三维Facet拟合,得到实际边缘点,从而完成图像边缘的精确定位.该方法通过小波变换粗定位这一前处理过程减少了Facet拟合的体素点数,加快了Facet模型三维边缘检测的速度.实验结果显示,本文方法不仅能得到与直接Facet模型效果相当的边缘,还能使Facet模型三维边缘检测的速度提高3.51~7.39倍,而且图像边缘越简单加速比越高.实验结果表明,基于小波定位和Facet模型的边缘检测方法可满足工业CT三维图像边缘检测对精度和速度的要求.

  1. From 3D to 4D: Integration of temporal information into CT angiography studies.

    Science.gov (United States)

    Haubenreisser, Holger; Bigdeli, Amir; Meyer, Mathias; Kremer, Thomas; Riester, Thomas; Kneser, Ulrich; Schoenberg, Stefan O; Henzler, Thomas

    2015-12-01

    CT angiography is the current clinical standard for the imaging many vascular illnesses. This is traditionally done with a single arterial contrast phase. However, advances in CT technology allow for a dynamic acquisition of the contrast bolus, thus adding temporal information to the examination. The aim of this article is to highlight the clinical possibilities of dynamic CTA using 2 examples. The accuracy of the detection and quantification of stenosis in patients with peripheral arterial occlusive disease, especially in stadium III and IV, is significantly improved when performing dynamic CTA examinations. The post-interventional follow-up of examinations of EVAR benefit from dynamic information, allowing for a higher sensitivity and specificity, as well as allowing more accurate classification of potential endoleaks. The described radiation dose for these dynamic examinations is low, but this can be further optimized by using lower tube voltages. There are a multitude of applications for dynamic CTA that need to be further explored in future studies.

  2. Terahertz Quantum Cascade Laser Based 3D Imaging Project

    Data.gov (United States)

    National Aeronautics and Space Administration — LongWave Photonics proposes a terahertz quantum-cascade laser based swept-source optical coherence tomography (THz SS-OCT) system for single-sided, 3D,...

  3. Holographic Image Plane Projection Integral 3D Display

    Data.gov (United States)

    National Aeronautics and Space Administration — In response to NASA's need for a 3D virtual reality environment providing scientific data visualization without special user devices, Physical Optics Corporation...

  4. Semiautomatic registration of 3D transabdominal ultrasound images for patient repositioning during postprostatectomy radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Presles, Benoît, E-mail: benoit.presles@creatis.insa-lyon.fr; Rit, Simon; Sarrut, David [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, Lyon F-69621, France and Léon Bérard Cancer Center, Université de Lyon, Lyon F-69373 (France); Fargier-Voiron, Marie; Liebgott, Hervé [Université de Lyon, CREATIS, CNRS UMR5220, Inserm U1044, INSA-Lyon, Université Lyon 1, Lyon F-69621 (France); Biston, Marie-Claude; Munoz, Alexandre; Pommier, Pascal [Léon Bérard Cancer Center, Université de Lyon, Lyon F-69373 (France); Lynch, Rod [The Andrew Love Cancer Centre, University Hospital Geelong, Geelong 3220 (Australia)

    2014-12-15

    Purpose: The aim of the present work is to propose and evaluate registration algorithms of three-dimensional (3D) transabdominal (TA) ultrasound (US) images to setup postprostatectomy patients during radiation therapy. Methods: Three registration methods have been developed and evaluated to register a reference 3D-TA-US image acquired during the planning CT session and a 3D-TA-US image acquired before each treatment session. The first method (method A) uses only gray value information, whereas the second one (method B) uses only gradient information. The third one (method C) combines both sets of information. All methods restrict the comparison to a region of interest computed from the dilated reference positioning volume drawn on the reference image and use mutual information as a similarity measure. The considered geometric transformations are translations and have been optimized by using the adaptive stochastic gradient descent algorithm. Validation has been carried out using manual registration by three operators of the same set of image pairs as the algorithms. Sixty-two treatment US images of seven patients irradiated after a prostatectomy have been registered to their corresponding reference US image. The reference registration has been defined as the average of the manual registration values. Registration error has been calculated by subtracting the reference registration from the algorithm result. For each session, the method has been considered a failure if the registration error was above both the interoperator variability of the session and a global threshold of 3.0 mm. Results: All proposed registration algorithms have no systematic bias. Method B leads to the best results with mean errors of −0.6, 0.7, and −0.2 mm in left–right (LR), superior–inferior (SI), and anterior–posterior (AP) directions, respectively. With this method, the standard deviations of the mean error are of 1.7, 2.4, and 2.6 mm in LR, SI, and AP directions, respectively

  5. 3-D Imaging Systems for Agricultural Applications—A Review

    Directory of Open Access Journals (Sweden)

    Manuel Vázquez-Arellano

    2016-04-01

    Full Text Available Efficiency increase of resources through automation of agriculture requires more information about the production process, as well as process and machinery status. Sensors are necessary for monitoring the status and condition of production by recognizing the surrounding structures such as objects, field structures, natural or artificial markers, and obstacles. Currently, three dimensional (3-D sensors are economically affordable and technologically advanced to a great extent, so a breakthrough is already possible if enough research projects are commercialized. The aim of this review paper is to investigate the state-of-the-art of 3-D vision systems in agriculture, and the role and value that only 3-D data can have to provide information about environmental structures based on the recent progress in optical 3-D sensors. The structure of this research consists of an overview of the different optical 3-D vision techniques, based on the basic principles. Afterwards, their application in agriculture are reviewed. The main focus lays on vehicle navigation, and crop and animal husbandry. The depth dimension brought by 3-D sensors provides key information that greatly facilitates the implementation of automation and robotics in agriculture.

  6. 3-D Imaging Systems for Agricultural Applications—A Review

    Science.gov (United States)

    Vázquez-Arellano, Manuel; Griepentrog, Hans W.; Reiser, David; Paraforos, Dimitris S.

    2016-01-01

    Efficiency increase of resources through automation of agriculture requires more information about the production process, as well as process and machinery status. Sensors are necessary for monitoring the status and condition of production by recognizing the surrounding structures such as objects, field structures, natural or artificial markers, and obstacles. Currently, three dimensional (3-D) sensors are economically affordable and technologically advanced to a great extent, so a breakthrough is already possible if enough research projects are commercialized. The aim of this review paper is to investigate the state-of-the-art of 3-D vision systems in agriculture, and the role and value that only 3-D data can have to provide information about environmental structures based on the recent progress in optical 3-D sensors. The structure of this research consists of an overview of the different optical 3-D vision techniques, based on the basic principles. Afterwards, their application in agriculture are reviewed. The main focus lays on vehicle navigation, and crop and animal husbandry. The depth dimension brought by 3-D sensors provides key information that greatly facilitates the implementation of automation and robotics in agriculture. PMID:27136560

  7. 3-D Imaging Systems for Agricultural Applications-A Review.

    Science.gov (United States)

    Vázquez-Arellano, Manuel; Griepentrog, Hans W; Reiser, David; Paraforos, Dimitris S

    2016-04-29

    Efficiency increase of resources through automation of agriculture requires more information about the production process, as well as process and machinery status. Sensors are necessary for monitoring the status and condition of production by recognizing the surrounding structures such as objects, field structures, natural or artificial markers, and obstacles. Currently, three dimensional (3-D) sensors are economically affordable and technologically advanced to a great extent, so a breakthrough is already possible if enough research projects are commercialized. The aim of this review paper is to investigate the state-of-the-art of 3-D vision systems in agriculture, and the role and value that only 3-D data can have to provide information about environmental structures based on the recent progress in optical 3-D sensors. The structure of this research consists of an overview of the different optical 3-D vision techniques, based on the basic principles. Afterwards, their application in agriculture are reviewed. The main focus lays on vehicle navigation, and crop and animal husbandry. The depth dimension brought by 3-D sensors provides key information that greatly facilitates the implementation of automation and robotics in agriculture.

  8. Dense 3d Point Cloud Generation from Uav Images from Image Matching and Global Optimazation

    Science.gov (United States)

    Rhee, S.; Kim, T.

    2016-06-01

    3D spatial information from unmanned aerial vehicles (UAV) images is usually provided in the form of 3D point clouds. For various UAV applications, it is important to generate dense 3D point clouds automatically from over the entire extent of UAV images. In this paper, we aim to apply image matching for generation of local point clouds over a pair or group of images and global optimization to combine local point clouds over the whole region of interest. We tried to apply two types of image matching, an object space-based matching technique and an image space-based matching technique, and to compare the performance of the two techniques. The object space-based matching used here sets a list of candidate height values for a fixed horizontal position in the object space. For each height, its corresponding image point is calculated and similarity is measured by grey-level correlation. The image space-based matching used here is a modified relaxation matching. We devised a global optimization scheme for finding optimal pairs (or groups) to apply image matching, defining local match region in image- or object- space, and merging local point clouds into a global one. For optimal pair selection, tiepoints among images were extracted and stereo coverage network was defined by forming a maximum spanning tree using the tiepoints. From experiments, we confirmed that through image matching and global optimization, 3D point clouds were generated successfully. However, results also revealed some limitations. In case of image-based matching results, we observed some blanks in 3D point clouds. In case of object space-based matching results, we observed more blunders than image-based matching ones and noisy local height variations. We suspect these might be due to inaccurate orientation parameters. The work in this paper is still ongoing. We will further test our approach with more precise orientation parameters.

  9. Superimposing of virtual graphics and real image based on 3D CAD information

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Proposes methods of transforming 3D CAD models into 2D graphics and recognizing 3D objects by features and superimposing VE built in computer onto real image taken by a CCD camera, and presents computer simulation results.

  10. Clinical usefulness of facial soft tissues thickness measurement using 3D computed tomographic images

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ho Gul; Kim, Kee Deog; Hu, Kyung Seok; Lee, Jae Bum; Park, Hyok [Maxtron Inc., Seoul (Korea, Republic of); Han, Seung Ho [Catholic Univ. of Korea, Seoul (Korea, Republic of); Choi, Seong Ho; Kim, Chong Kwan; Park, Chang Seo [Yonsei Univ., Seoul (Korea, Republic of)

    2006-06-15

    To evaluate clinical usefulness of facial soft tissue thickness measurement using 3D computed tomographic images. One cadaver that had sound facial soft tissues was chosen for the study. The cadaver was scanned with a Helical CT under following scanning protocols about slice thickness and table speed: 3 mm and 3 mm/sec, 5 mm and 5 mm/sec, 7 mm and 7 mm/sec. The acquired data were reconstructed 1.5, 2.5, 3.5 mm reconstruction interval respectively and the images were transferred to a personal computer. Using a program developed to measure facial soft tissue thickness in 3D image, the facial soft tissue thickness was measured. After the ten-time repeation of the measurement for ten times, repeated measure analysis of variance (ANOVA) was adopted to compare and analyze the measurements using the three scanning protocols. Comparison according to the areas was analysed by Mann-Whitney test. There were no statistically significant intraobserver differences in the measurements of the facial soft tissue thickness using the three scanning protocols (p>0.05). There were no statistically significant differences between measurements in the 3 mm slice thickness and those in the 5 mm, 7 mm slice thickness (p>0.05). There were statistical differences in the 14 of the total 30 measured points in the 5 mm slice thickness and 22 in the 7 mm slice thickness. The facial soft tissue thickness measurement using 3D images of 7 mm slice thickness is acceptable clinically, but those of 5 mm slice thickness is recommended for the more accurate measurement.

  11. Soft computing approach to 3D lung nodule segmentation in CT.

    Science.gov (United States)

    Badura, P; Pietka, E

    2014-10-01

    This paper presents a novel, multilevel approach to the segmentation of various types of pulmonary nodules in computed tomography studies. It is based on two branches of computational intelligence: the fuzzy connectedness (FC) and the evolutionary computation. First, the image and auxiliary data are prepared for the 3D FC analysis during the first stage of an algorithm - the masks generation. Its main goal is to process some specific types of nodules connected to the pleura or vessels. It consists of some basic image processing operations as well as dedicated routines for the specific cases of nodules. The evolutionary computation is performed on the image and seed points in order to shorten the FC analysis and improve its accuracy. After the FC application, the remaining vessels are removed during the postprocessing stage. The method has been validated using the first dataset of studies acquired and described by the Lung Image Database Consortium (LIDC) and by its latest release - the LIDC-IDRI (Image Database Resource Initiative) database.

  12. Present and future in the use of micro-CT scanner 3D analysis for the study of dental and root canal morphology

    Directory of Open Access Journals (Sweden)

    Nicola M. Grande

    2012-01-01

    Full Text Available The goal of the present article is to illustrate and analyze the applications and the potential of microcomputed tomography (micro-CT in the analysis of tooth anatomy and root canal morphology. The authors performed a micro-CT analysis of the following different teeth: maxillary first molars with a second canal in the mesiobuccal (MB root, mandibular first molars with complex anatomy in the mesial root, premolars with single and double roots and with complicated apical anatomy. The hardware device used in this study was a desktop X-ray microfocus CT scanner (SkyScan 1072, SkyScan bvba, Aartselaar, Belgium. A specific software ResolveRT Amira (Visage Imaging was used for the 3D analysis and imaging. The authors obtained three-dimensional images from 15 teeth. It was possible to precisely visualize and analyze external and internal anatomy of teeth, showing the finest details. Among the 5 upper molars analyzed, in three cases, the MB canals joined into one canal, while in the other two molars the two mesial canals were separate. Among the lower molars two of the five samples exhibited a single canal in the mesial root, which had a broad, flat appearance in a mesiodistal dimension. In the five premolar teeth, the canals were independent; however, the apical delta and ramifications of the root canals were quite complex. Micro-CT offers a simple and reproducible technique for 3D noninvasive assessment of the anatomy of root canal systems.

  13. Present and future in the use of micro-CT scanner 3D analysis for the study of dental and root canal morphology.

    Science.gov (United States)

    Grande, Nicola M; Plotino, Gianluca; Gambarini, Gianluca; Testarelli, Luca; D'Ambrosio, Ferdinando; Pecci, Raffaella; Bedini, Rossella

    2012-01-01

    The goal of the present article is to illustrate and analyze the applications and the potential of microcomputed tomography (micro-CT) in the analysis of tooth anatomy and root canal morphology. The authors performed a micro-CT analysis of the following different teeth: maxillary first molars with a second canal in the mesiobuccal (MB) root, mandibular first molars with complex anatomy in the mesial root, premolars with single and double roots and with complicated apical anatomy. The hardware device used in this study was a desktop X-ray microfocus CT scanner (SkyScan 1072, SkyScan bvba, Aartselaar, Belgium). A specific software ResolveRT Amira (Visage Imaging) was used for the 3D analysis and imaging. The authors obtained three-dimensional images from 15 teeth. It was possible to precisely visualize and analyze external and internal anatomy of teeth, showing the finest details. Among the 5 upper molars analyzed, in three cases, the MB canals joined into one canal, while in the other two molars the two mesial canals were separate. Among the lower molars two of the five samples exhibited a single canal in the mesial root, which had a broad, flat appearance in a mesiodistal dimension. In the five premolar teeth, the canals were independent; however, the apical delta and ramifications of the root canals were quite complex. Micro-CT offers a simple and reproducible technique for 3D noninvasive assessment of the anatomy of root canal systems.

  14. Multimodal Registration and Fusion for 3D Thermal Imaging

    Directory of Open Access Journals (Sweden)

    Moulay A. Akhloufi

    2015-01-01

    Full Text Available 3D vision is an area of computer vision that has attracted a lot of research interest and has been widely studied. In recent years we witness an increasing interest from the industrial community. This interest is driven by the recent advances in 3D technologies, which enable high precision measurements at an affordable cost. With 3D vision techniques we can conduct advanced manufactured parts inspections and metrology analysis. However, we are not able to detect subsurface defects. This kind of detection is achieved by other techniques, like infrared thermography. In this work, we present a new registration framework for 3D and thermal infrared multimodal fusion. The resulting fused data can be used for advanced 3D inspection in Nondestructive Testing and Evaluation (NDT&E applications. The fusion permits the simultaneous visible surface and subsurface inspections to be conducted in the same process. Experimental tests were conducted with different materials. The obtained results are promising and show how these new techniques can be used efficiently in a combined NDT&E-Metrology analysis of manufactured parts, in areas such as aerospace and automotive.

  15. 3D-CT evaluation of secondary alveolar bone grafts in alveolar clefts

    Energy Technology Data Exchange (ETDEWEB)

    Naitoh, Hiroshi; Nishimura, Yoshihiko [Kyoto Univ. (Japan). Graduate School of Medicine; Yamawaki, Yoshiroh [Kyoto Katsura Hospital (Japan); Morimoto, Naoki [Kobe City General Hospital (Japan)

    2002-07-01

    From 1994 to 2000, we treated 116 patients with cleft alveolus by secondary alveolar bone grafts, and 48 of them were evaluated morphologically with 3D-CT. The frequency of successful bony bridging was significantly higher in the group whose grafts were completely enveloped (including the anterior alveolar ridge) with a mucoperiosteal flap. The frequency was also significantly higher in the group who underwent bone grafts at the age of 13 or less, and canine eruptions did not influence the ratio. Some cases showed such an improved growth pattern of grafted bone that the shape of the affected maxilla resembled that of the normal side, after long-term follow-up observations. The growth increment was remarkable in anterior maxillary height. Orthodontic management guides the canine or incisor into the reconstructed area of the previous cleft. We surmise that the new occlusal position puts pressure on the grafted bone and promotes further osteogenesis. These findings show that it is important to produce sufficient bony bridge to guide the canine or incisor, not the volume of grafted bone, in secondary alveolar bone grafts. Long-term follow-up observation, after more than 2-3 years, is also necessary to evaluate secondary alveolar bone grafts. (author)

  16. Comparison of Simultaneous and Sequential Two-View Registration for 3D/2D Registration of Vascular Images

    OpenAIRE

    Pathak, Chetna; Van Horn, Mark; Weeks, Susan; Bullitt, Elizabeth

    2005-01-01

    Accurate 3D/2D vessel registration is complicated by issues of image quality, occlusion, and other problems. This study performs a quantitative comparison of 3D/2D vessel registration in which vessels segmented from preoperative CT or MR are registered with biplane x-ray angiograms by either a) simultaneous two-view registration with advance calculation of the relative pose of the two views, or b) sequential registration with each view. We conclude on the basis of phantom studies that, even i...

  17. High-Performance 3D Image Processing Architectures for Image-Guided Interventions

    Science.gov (United States)

    2008-01-01

    Circuits and Systems, vol. 1 (2), 2007, pp. 116-127. iv • O. Dandekar, C. Castro- Pareja , and R. Shekhar, “FPGA-based real-time 3D image...How low can we go?,” presented at IEEE International Symposium on Biomedical Imaging, 2006, pp. 502-505. • C. R. Castro- Pareja , O. Dandekar, and R...Venugopal, C. R. Castro- Pareja , and O. Dandekar, “An FPGA-based 3D image processor with median and convolution filters for real-time applications,” in

  18. Robust Reconstruction and Generalized Dual Hahn Moments Invariants Extraction for 3D Images

    Science.gov (United States)

    Mesbah, Abderrahim; Zouhri, Amal; El Mallahi, Mostafa; Zenkouar, Khalid; Qjidaa, Hassan

    2017-03-01

    In this paper, we introduce a new set of 3D weighed dual Hahn moments which are orthogonal on a non-uniform lattice and their polynomials are numerically stable to scale, consequent, producing a set of weighted orthonormal polynomials. The dual Hahn is the general case of Tchebichef and Krawtchouk, and the orthogonality of dual Hahn moments eliminates the numerical approximations. The computational aspects and symmetry property of 3D weighed dual Hahn moments are discussed in details. To solve their inability to invariability of large 3D images, which cause to overflow issues, a generalized version of these moments noted 3D generalized weighed dual Hahn moment invariants are presented where whose as linear combination of regular geometric moments. For 3D pattern recognition, a generalized expression of 3D weighted dual Hahn moment invariants, under translation, scaling and rotation transformations, have been proposed where a new set of 3D-GWDHMIs have been provided. In experimental studies, the local and global capability of free and noisy 3D image reconstruction of the 3D-WDHMs has been compared with other orthogonal moments such as 3D Tchebichef and 3D Krawtchouk moments using Princeton Shape Benchmark database. On pattern recognition using the 3D-GWDHMIs like 3D object descriptors, the experimental results confirm that the proposed algorithm is more robust than other orthogonal moments for pattern classification of 3D images with and without noise.

  19. GPU accelerated generation of digitally reconstructed radiographs for 2-D/3-D image registration.

    Science.gov (United States)

    Dorgham, Osama M; Laycock, Stephen D; Fisher, Mark H

    2012-09-01

    Recent advances in programming languages for graphics processing units (GPUs) provide developers with a convenient way of implementing applications which can be executed on the CPU and GPU interchangeably. GPUs are becoming relatively cheap, powerful, and widely available hardware components, which can be used to perform intensive calculations. The last decade of hardware performance developments shows that GPU-based computation is progressing significantly faster than CPU-based computation, particularly if one considers the execution of highly parallelisable algorithms. Future predictions illustrate that this trend is likely to continue. In this paper, we introduce a way of accelerating 2-D/3-D image registration by developing a hybrid system which executes on the CPU and utilizes the GPU for parallelizing the generation of digitally reconstructed radiographs (DRRs). Based on the advancements of the GPU over the CPU, it is timely to exploit the benefits of many-core GPU technology by developing algorithms for DRR generation. Although some previous work has investigated the rendering of DRRs using the GPU, this paper investigates approximations which reduce the computational overhead while still maintaining a quality consistent with that needed for 2-D/3-D registration with sufficient accuracy to be clinically acceptable in certain applications of radiation oncology. Furthermore, by comparing implementations of 2-D/3-D registration on the CPU and GPU, we investigate current performance and propose an optimal framework for PC implementations addressing the rigid registration problem. Using this framework, we are able to render DRR images from a 256×256×133 CT volume in ~24 ms using an NVidia GeForce 8800 GTX and in ~2 ms using NVidia GeForce GTX 580. In addition to applications requiring fast automatic patient setup, these levels of performance suggest image-guided radiation therapy at video frame rates is technically feasible using relatively low cost PC

  20. Acetabular fractures: what radiologists should know and how 3D CT can aid classification.

    Science.gov (United States)

    Scheinfeld, Meir H; Dym, Akiva A; Spektor, Michael; Avery, Laura L; Dym, R Joshua; Amanatullah, Derek F

    2015-01-01

    Correct recognition, description, and classification of acetabular fractures is essential for efficient patient triage and treatment. Acetabular fractures may result from high-energy trauma or low-energy trauma in the elderly. The most widely used acetabular fracture classification system among radiologists and orthopedic surgeons is the system of Judet and Letournel, which includes five elementary (or elemental) and five associated fractures. The elementary fractures are anterior wall, posterior wall, anterior column, posterior column, and transverse. The associated fractures are all combinations or partial combinations of the elementary fractures and include transverse with posterior wall, T-shaped, associated both column, anterior column or wall with posterior hemitransverse, and posterior column with posterior wall. The most unique fracture is the associated both column fracture, which completely dissociates the acetabular articular surface from the sciatic buttress. Accurate categorization of acetabular fractures is challenging because of the complex three-dimensional (3D) anatomy of the pelvis, the rarity of certain acetabular fracture variants, and confusing nomenclature. Comparing a 3D image of the fractured acetabulum with a standard diagram containing the 10 Judet and Letournel categories of acetabular fracture and using a flowchart algorithm are effective ways of arriving at the correct fracture classification. Online supplemental material is available for this article.

  1. Display of travelling 3D scenes from single integral-imaging capture

    Science.gov (United States)

    Martinez-Corral, Manuel; Dorado, Adrian; Hong, Seok-Min; Sola-Pikabea, Jorge; Saavedra, Genaro

    2016-06-01

    Integral imaging (InI) is a 3D auto-stereoscopic technique that captures and displays 3D images. We present a method for easily projecting the information recorded with this technique by transforming the integral image into a plenoptic image, as well as choosing, at will, the field of view (FOV) and the focused plane of the displayed plenoptic image. Furthermore, with this method we can generate a sequence of images that simulates a camera travelling through the scene from a single integral image. The application of this method permits to improve the quality of 3D display images and videos.

  2. 3D fingerprint imaging system based on full-field fringe projection profilometry

    Science.gov (United States)

    Huang, Shujun; Zhang, Zonghua; Zhao, Yan; Dai, Jie; Chen, Chao; Xu, Yongjia; Zhang, E.; Xie, Lili

    2014-01-01

    As an unique, unchangeable and easily acquired biometrics, fingerprint has been widely studied in academics and applied in many fields over the years. The traditional fingerprint recognition methods are based on the obtained 2D feature of fingerprint. However, fingerprint is a 3D biological characteristic. The mapping from 3D to 2D loses 1D information and causes nonlinear distortion of the captured fingerprint. Therefore, it is becoming more and more important to obtain 3D fingerprint information for recognition. In this paper, a novel 3D fingerprint imaging system is presented based on fringe projection technique to obtain 3D features and the corresponding color texture information. A series of color sinusoidal fringe patterns with optimum three-fringe numbers are projected onto a finger surface. From another viewpoint, the fringe patterns are deformed by the finger surface and captured by a CCD camera. 3D shape data of the finger can be obtained from the captured fringe pattern images. This paper studies the prototype of the 3D fingerprint imaging system, including principle of 3D fingerprint acquisition, hardware design of the 3D imaging system, 3D calibration of the system, and software development. Some experiments are carried out by acquiring several 3D fingerprint data. The experimental results demonstrate the feasibility of the proposed 3D fingerprint imaging system.

  3. PSMA PET/CT with Glu-urea-Lys-(Ahx)-[{sup 68}Ga(HBED-CC)] versus 3D CT volumetric lymph node assessment in recurrent prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Giesel, Frederik L.; Haberkorn, U. [University of Heidelberg, Department of Nuclear Medicine, INF 400, University Hospital Heidelberg, Heidelberg (Germany); DKFZ, Cooperation Unit Nuclear Medicine, Heidelberg (Germany); Fiedler, H.; Stefanova, M.; Afshar-Oromieh, A.; Kratochwil, C. [University of Heidelberg, Department of Nuclear Medicine, INF 400, University Hospital Heidelberg, Heidelberg (Germany); Sterzing, F. [University of Heidelberg, Department of RadioOncology, Heidelberg (Germany); Rius, M. [European Commission, Institute for Transuranium Elements (ITU), Karlsruhe (Germany); DKFZ, Cooperation Unit Nuclear Medicine, Heidelberg (Germany); Kopka, K.; Moltz, J.H. [German Cancer Research Center (dkfz), Radiopharmaceutical Chemistry, Heidelberg (Germany); Choyke, P.L. [National Cancer Institute, Molecular Imaging Program, Bethesda (United States)

    2015-11-15

    PET/CT with the PSMA ligand is a powerful new method for the early detection of nodal metastases in patients with biochemical relapse. The purpose of this retrospective investigation was to evaluate the volume and dimensions of nodes identified by Glu-urea-Lys-(Ahx)-[{sup 68}Ga(HBED-CC)] ({sup 68}Ga-PSMA-11) in the setting of recurrent prostate cancer. All PET/CT images were acquired 60 ± 10 min after intravenous injection of {sup 68}Ga-PSMA-11 (mean dose 176 MBq). In 21 patients with recurrent prostate cancer and rising PSA, 49 PSMA-positive lymph nodes were identified. Using semiautomated lymph node segmentation software, node volume and short-axis and long-axis dimensions were measured and compared with the maximum standardized uptake values (SUVmax). Round nodes greater than or equal to 8 mm were considered positive by morphological criteria alone. The percentage of nodes identified by elevated SUVmax but not by conventional morphological criteria was determined. The mean volume of {sup 68}Ga-PSMA-11-positive nodes was 0.5 ml (range 0.2 - 2.3 ml), and the mean short-axis diameter was 5.8 mm (range 2.4 - 13.3 mm). In 7 patients (33.3 %) with 31 PSMA-positive nodes only 11 (36 %) were morphologically positive based on diameters >8 mm on CT. In the remaining 14 patients (66.7 %), 18 (37 %) of PSMA positive lymph nodes had short-axis diameters <8 mm with a mean short-axis diameter of 5.0 mm (range 2.4 - 7.9 mm). Thus, in this population, {sup 68}Ga-PSMA-11 PET/CT detected nodal recurrence in two-thirds of patients who would have been missed using conventional morphological criteria. {sup 68}Ga-PSMA-11 PET/CT is more sensitive than CT based 3D volumetric lymph node evaluation in determining the node status of patients with recurrent prostate cancer, and is a promising method of restaging prostate cancers in this setting. (orig.)

  4. Accuracy of 3D Imaging Software in Cephalometric Analysis

    Science.gov (United States)

    2013-06-21

    orthodontic software program ( Dolphin 3D, mfg, city, state) used for measurement and analysis of craniofacial dimensions. Three-dimensional reconstructions...143(8), 899-902. Baik H, Jeon J, Lee H. (2007). Facial soft tissue analysis of Korean adults with normal occlusion using a 3-dimensional laser

  5. 3D Imaging Technology’s Narrative Appropriation in Cinema

    NARCIS (Netherlands)

    Kiss, Miklós; van den Oever, Annie; Fossati, Giovanna

    2016-01-01

    This chapter traces the cinematic history of stereoscopy by focusing on the contemporary dispute about the values of 3D technology, which are seen as either mere visual attraction or as a technique that perfects the cinematic illusion through increasing perceptual immersion. By taking a neutral stan

  6. Emphysema quantification on low-dose CT using percentage of low-attenuation volume and size distribution of low-attenuation lung regions: Effects of adaptive iterative dose reduction using 3D processing

    Energy Technology Data Exchange (ETDEWEB)

    Nishio, Mizuho, E-mail: nmizuho@med.kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Matsumoto, Sumiaki, E-mail: sumatsu@med.kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Seki, Shinichiro, E-mail: sshin@med.kobe-u.ac.jp [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Koyama, Hisanobu, E-mail: hkoyama@med.kobe-u.ac.jp [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017 (Japan); Fujisawa, Yasuko, E-mail: yasuko1.fujisawa@toshiba.co.jp [Toshiba Medical Systems Corporation, 1385 Shimoishigami, Otawara, Tochigi 324-8550 (Japan); Sugihara, Naoki, E-mail: naoki.sugihara@toshiba.co.jp [Toshiba Medical Systems Corporation, 1385 Shimoishigami, Otawara, Tochigi 324-8550 (Japan); and others

    2014-12-15

    Highlights: • Emphysema quantification (LAV% and D) was affected by image noise on low-dose CT. • For LAV% and D, AIDR 3D improved agreement of quantification on low-dose CT. • AIDR 3D has the potential to quantify emphysema accurately on low-dose CT. - Abstract: Purpose: To evaluate the effects of adaptive iterative dose reduction using 3D processing (AIDR 3D) for quantification of two measures of emphysema: percentage of low-attenuation volume (LAV%) and size distribution of low-attenuation lung regions. Method and materials: : Fifty-two patients who underwent standard-dose (SDCT) and low-dose CT (LDCT) were included. SDCT without AIDR 3D, LDCT without AIDR 3D, and LDCT with AIDR 3D were used for emphysema quantification. First, LAV% was computed at 10 thresholds from −990 to −900 HU. Next, at the same thresholds, linear regression on a log–log plot was used to compute the power law exponent (D) for the cumulative frequency-size distribution of low-attenuation lung regions. Bland–Altman analysis was used to assess whether AIDR 3D improved agreement between LDCT and SDCT for emphysema quantification of LAV% and D. Results: The mean relative differences in LAV% between LDCT without AIDR 3D and SDCT were 3.73%–88.18% and between LDCT with AIDR 3D and SDCT were −6.61% to 0.406%. The mean relative differences in D between LDCT without AIDR 3D and SDCT were 8.22%–19.11% and between LDCT with AIDR 3D and SDCT were 1.82%–4.79%. AIDR 3D improved agreement between LDCT and SDCT at thresholds from −930 to −990 HU for LAV% and at all thresholds for D. Conclusion: AIDR 3D improved the consistency between LDCT and SDCT for emphysema quantification of LAV% and D.

  7. Evaluation of failing hemodialysis fistulas with multidetector CT angiography: Comparison of different 3D planes

    Energy Technology Data Exchange (ETDEWEB)

    Karadeli, E. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey); Tarhan, N.C. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey)], E-mail: caglat@baskent-ank.edu.tr; Ulu, E.M. Kayahan; Tutar, N.U. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey); Basaran, O. [Department of General Surgery, Baskent University, Faculty of Medicine, Ankara (Turkey); Coskun, M.; Niron, E.A. [Department of Radiology, Baskent University, Faculty of Medicine, Ankara (Turkey)

    2009-01-15

    Purpose: To evaluate failing hemodialysis fistula complications using 16-detector MDCTA, and to assess the accuracies of different 3D planes. Materials and methods: Thirty patients (16 men, 14 women, aged 27-79 years) were referred for hemodialysis access dysfunction. Thirty-one MDCTA exams were done prior to fistulography. For MDCTA, contrast was administered (2 mL/kg at 5 mL/s) via a peripheral vein in the contralateral arm. Axial MIP, coronal MIP, and VRT images were constructed. Venous complications were evaluated on axial source images, on each 3D plane, and on all-planes together. Results were analyzed using McNemar test. Results: Axial MIP, VRT and all-planes evaluations were most sensitive for fistula site detection (93%). Coronal MIP had the highest sensitivity, specificity and accuracy (35%, 96%, and 85%, respectively) for detecting venous stenosis. VRT and all-planes had the highest sensitivity and accuracy for detecting aneurysms (100%). All-planes and axial MIP were most sensitive for detecting venous occlusion (61% and 54%). Comparisons of detection frequencies for each venous pathology between the five categories of MDCTA revealed no significant differences (P > 0.05). MDCTA additionally showed 3 partially thrombosed aneurysms, 4 anastomosis site stenosis and 12 arterial complications. Conclusion: MDCTA overall gives low sensitivity for detection of central vein stenosis and moderate sensitivity for occlusion. For most pathology, all-planes evaluation of MDCTA gives highest sensitivity and accuracy rates when compared to other planes. For venous stenosis and occlusion, MDCTA should be considered when ultrasonography and fistulography are inconclusive. MDCTA is helpful in identifying aneurysms, collaterals, partial venous thromboses and additional arterial, anastomosis site pathologies.

  8. 360 degree realistic 3D image display and image processing from real objects

    Science.gov (United States)

    Luo, Xin; Chen, Yue; Huang, Yong; Tan, Xiaodi; Horimai, Hideyoshi

    2016-09-01

    A 360-degree realistic 3D image display system based on direct light scanning method, so-called Holo-Table has been introduced in this paper. High-density directional continuous 3D motion images can be displayed easily with only one spatial light modulator. Using the holographic screen as the beam deflector, 360-degree full horizontal viewing angle was achieved. As an accompany part of the system, CMOS camera based image acquisition platform was built to feed the display engine, which can take a full 360-degree continuous imaging of the sample at the center. Customized image processing techniques such as scaling, rotation, format transformation were also developed and embedded into the system control software platform. In the end several samples were imaged to demonstrate the capability of our system.

  9. 360 degree realistic 3D image display and image processing from real objects

    Science.gov (United States)

    Luo, Xin; Chen, Yue; Huang, Yong; Tan, Xiaodi; Horimai, Hideyoshi

    2016-12-01

    A 360-degree realistic 3D image display system based on direct light scanning method, so-called Holo-Table has been introduced in this paper. High-density directional continuous 3D motion images can be displayed easily with only one spatial light modulator. Using the holographic screen as the beam deflector, 360-degree full horizontal viewing angle was achieved. As an accompany part of the system, CMOS camera based image acquisition platform was built to feed the display engine, which can take a full 360-degree continuous imaging of the sample at the center. Customized image processing techniques such as scaling, rotation, format transformation were also developed and embedded into the system control software platform. In the end several samples were imaged to demonstrate the capability of our system.

  10. Mobile 3D rotational X-ray: comparison with CT in sinus surgery

    Energy Technology Data Exchange (ETDEWEB)

    Carelsen, B. [Dept. of Medical Physics, Academic Medical Center, Amsterdam (Netherlands); Bakker, N.H. [Dept. of Man-Machine Systems, Delft Univ. of Technology, Delft (Netherlands); Boon, S.N. [General X-ray Surgery, Philips Medical Systems, Best (Netherlands); Fokkens, W.J. [ENT Dept., Academic Medical Center, Amsterdam (Netherlands); Freling, N.J.M. [Radiology Dept., Academic Medical Center, Amsterdam (Netherlands); Noordhoek, N.J. [X-ray Pre-development, Philips Medical Systems, Best (Netherlands)

    2004-11-01

    Clinical evaluation of a 3D rotational X-ray (3D-RX) system, comprising a modified Philips BV Pulsera C-arm system and a Philips 3D-RA workstation, demonstrates good diagnostic accuracy in functional endoscopic sinus surgery.

  11. Automatic Segmentation of Lung Carcinoma Using 3D Texture Features in 18-FDG PET/CT

    Directory of Open Access Journals (Sweden)

    Daniel Markel

    2013-01-01

    Full Text Available Target definition is the largest source of geometric uncertainty in radiation therapy. This is partly due to a lack of contrast between tumor and healthy soft tissue for computed tomography (CT and due to blurriness, lower spatial resolution, and lack of a truly quantitative unit for positron emission tomography (PET. First-, second-, and higher-order statistics, Tamura, and structural features were characterized for PET and CT images of lung carcinoma and organs of the thorax. A combined decision tree (DT with K-nearest neighbours (KNN classifiers as nodes containing combinations of 3 features were trained and used for segmentation of the gross tumor volume. This approach was validated for 31 patients from two separate institutions and scanners. The results were compared with thresholding approaches, the fuzzy clustering method, the 3-level fuzzy locally adaptive Bayesian algorithm, the multivalued level set algorithm, and a single KNN using Hounsfield units and standard uptake value. The results showed the DTKNN classifier had the highest sensitivity of 73.9%, second highest average Dice coefficient of 0.607, and a specificity of 99.2% for classifying voxels when using a probabilistic ground truth provided by simultaneous truth and performance level estimation using contours drawn by 3 trained physicians.

  12. High density resolution synchrotron radiation based x-ray microtomography (SR μCT) for quantitative 3D-morphometrics in zoological sciences

    Science.gov (United States)

    Nickel, Michael; Hammel, Jörg U.; Herzen, Julia; Bullinger, Eric; Beckmann, Felix

    2008-08-01

    Zoological sciences widely rely on morphological data to reconstruct and understand body structures of animals. The best suitable methods like tomography allow for a direct representation of 3D-structures. In recent years, synchrotron radiation based x-ray microtomography (SR μCT) placed high resolutions to the disposal of morphologists. With the development of highly brilliant and collimated third generation synchrotron sources, phase contrast SR μCT became widely available. A number of scientific contributions stressed the superiority of phase contrast over absorption contrast. However, here we demonstrate the power of high density resolution methods based on absorption-contrast SRμCT for quantitative 3D-measurements of tissues and other delicate bio-structures in zoological sciences. We used beamline BW2 at DORIS III (DESY, Hamburg, Germany) to perform microtomography on tissue and mineral skeletons of marine sponges (Porifera) which were shock frozen and/or fixed in a glutamate osmium tetroxide solution, followed by critical point drying. High density resolution tomographic reconstructions allowed running quantitative 3D-image analyses in Matlab and ImageJ. By applying contrast and shape rule based algorithms we semi-automatically extracted and measured sponge body structures like mineral spicules, elements of the canal system or tissue structures. This lead to a better understanding of sponge biology: from skeleton functional morphology and internal water flow regimes to body contractility. Our high density resolution based quantitative approach can be applied to a wide variety of biological structures. However, two prerequisites apply: (1) maximum density resolution is necessary; (2) edge effects as seen for example in phase outline contrast SR μCT must not be present. As a consequence, to allow biological sciences to fully exploit the power of SR μCT further increase of density resolution in absorption contrast methods is desirable.

  13. Confocal Image 3D Surface Measurement with Optical Fiber Plate

    Institute of Scientific and Technical Information of China (English)

    WANG Zhao; ZHU Sheng-cheng; LI Bing; TAN Yu-shan

    2004-01-01

    A whole-field 3D surface measurement system for semiconductor wafer inspection is described.The system consists of an optical fiber plate,which can split the light beam into N2 subbeams to realize the whole-field inspection.A special prism is used to separate the illumination light and signal light.This setup is characterized by high precision,high speed and simple structure.

  14. CT angiography versus 3D rotational angiography in patients with subarachnoid hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Bechan, R.S.; Peluso, J.P.; Sluzewski, M.; Rooij, W.J. van [Sint Elisabeth Ziekenhuis Tilburg, Department of Radiology, Tilburg (Netherlands); Rooij, S.B. van [Medisch Centrum Alkmaar, Department of Radiology, Alkmaar (Netherlands); Sprengers, M.E.; Majoie, C.B. [Academisch Medisch Centrum, Department of Radiology, Amsterdam (Netherlands)

    2015-12-15

    CT angiography (CTA) is increasingly used as primary diagnostic tool to replace digital subtraction angiography (DSA) in patients with subarachnoid hemorrhage (SAH). However, 3D rotational angiography (3DRA) has substituted DSA as a reference standard. In this prospective observational study, we compare CTA with 3DRA of all cerebral vessels in a large cohort of patients with SAH. Of 179 consecutive patients with SAH admitted between March 2013 and July 2014, 139 underwent 64- to 256-detector row CTA followed by complete cerebral 3DRA within 24 h. In 86 patients (62 %), 3DRA was performed under general anesthesia. Two observers from outside hospitals reviewed CTA data. In 118 of 139 patients (85 %), 3DRA diagnosed the cause of hemorrhage: 113 ruptured aneurysms, three arterial dissections, one micro-arteriovenous malformation (AVM), and one reversible vasoconstriction syndrome. On CTA, both observers missed all five non-aneurysmal causes of SAH. Sensitivity of CTA in depicting ruptured aneurysms was 0.88-0.91, and accuracy was 0.88-0.92. Of 113 ruptured aneurysms, 28 were ≤3 mm (25 %) and of 95 additional aneurysms, 71 were ≤3 mm (75 %). Sensitivity of depicting aneurysms ≤3 mm was 0.28-0.43. Of 95 additional aneurysms, the two raters missed 65 (68 %) and 58 (61 %). Sensitivity in detection was lower in aneurysms of the internal carotid artery than in other locations. CTA had some limitations as primary diagnostic tool in patients with SAH. All non-aneurysmal causes for SAH and one in ten ruptured aneurysms were missed. Performance of CTA was poor in aneurysms ≤3 mm. The majority of additional aneurysms were not depicted on CTA. (orig.)

  15. Analysis of bite marks in foodstuffs by computer tomography (cone beam CT)--3D reconstruction.

    Science.gov (United States)

    Marques, Jeidson; Musse, Jamilly; Caetano, Catarina; Corte-Real, Francisco; Corte-Real, Ana Teresa

    2013-12-01

    The use of three-dimensional (3D) analysis of forensic evidence is highlighted in comparison with traditional methods. This three-dimensional analysis is based on the registration of the surface from a bitten object. The authors propose to use Cone Beam Computed Tomography (CBCT), which is used in dental practice, in order to study the surface and interior of bitten objects and dental casts of suspects. In this study, CBCT is applied to the analysis of bite marks in foodstuffs, which may be found in a forensic case scenario. 6 different types of foodstuffs were used: chocolate, cheese, apple, chewing gum, pizza and tart (flaky pastry and custard). The food was bitten into and dental casts of the possible suspects were made. The dental casts and bitten objects were registered using an x-ray source and the CBCT equipment iCAT® (Pennsylvania, EUA). The software InVivo5® (Anatomage Inc, EUA) was used to visualize and analyze the tomographic slices and 3D reconstructions of the objects. For each material an estimate of its density was assessed by two methods: HU values and specific gravity. All the used materials were successfully reconstructed as good quality 3D images. The relative densities of the materials in study were compared. Amongst the foodstuffs, the chocolate had the highest density (median value 100.5 HU and 1,36 g/cm(3)), while the pizza showed to have the lowest (median value -775 HU and 0,39 g/cm(3)), on both scales. Through tomographic slices and three-dimensional reconstructions it was possible to perform the metric analysis of the bite marks in all the foodstuffs, except for the pizza. These measurements could also be obtained from the dental casts. The depth of the bite mark was also successfully determined in all the foodstuffs except for the pizza. Cone Beam Computed Tomography has the potential to become an important tool for forensic sciences, namely for the registration and analysis of bite marks in foodstuffs that may be found in a crime

  16. Advanced 3-D Ultrasound Imaging: 3-D Synthetic Aperture Imaging using Fully Addressed and Row-Column Addressed 2-D Transducer Arrays

    DEFF Research Database (Denmark)

    Bouzari, Hamed

    companies have produced ultrasound scanners using 2-D transducer arrays with enough transducer elements to produce high quality 3-D images. Because of the large matrix transducers with integrated custom electronics, these systems are extremely expensive. The relatively low price of ultrasound scanners......Compared with conventional 2-D ultrasound imaging, real-time 3-D (or 4-D) ultrasound imaging has several advantages, resulting in a significant progress in the ultrasound imaging instrumentation over the past decade. Viewing the patient’s anatomy as a volume helps physicians to comprehend...... the important diagnostic information in a noninvasive manner. Diagnostic and therapeutic decisions often require accurate estimates of e.g., organ, cyst, or tumor volumes. 3-D ultrasound imaging can provide these measurements without relying on the geometrical assumptions and operator-dependent skills involved...

  17. Liver recognition based on statistical shape model in CT images

    Science.gov (United States)

    Xiang, Dehui; Jiang, Xueqing; Shi, Fei; Zhu, Weifang; Chen, Xinjian

    2016-03-01

    In this paper, an automatic method is proposed to recognize the liver on clinical 3D CT images. The proposed method effectively use statistical shape model of the liver. Our approach consist of three main parts: (1) model training, in which shape variability is detected using principal component analysis from the manual annotation; (2) model localization, in which a fast Euclidean distance transformation based method is able to localize the liver in CT images; (3) liver recognition, the initial mesh is locally and iteratively adapted to the liver boundary, which is constrained with the trained shape model. We validate our algorithm on a dataset which consists of 20 3D CT images obtained from different patients. The average ARVD was 8.99%, the average ASSD was 2.69mm, the average RMSD was 4.92mm, the average MSD was 28.841mm, and the average MSD was 13.31%.

  18. Geometrical Calibration of X-Ray Imaging With RGB Cameras for 3D Reconstruction.

    Science.gov (United States)

    Albiol, Francisco; Corbi, Alberto; Albiol, Alberto

    2016-08-01

    We present a methodology to recover the geometrical calibration of conventional X-ray settings with the help of an ordinary video camera and visible fiducials that are present in the scene. After calibration, equivalent points of interest can be easily identifiable with the help of the epipolar geometry. The same procedure also allows the measurement of real anatomic lengths and angles and obtains accurate 3D locations from image points. Our approach completely eliminates the need for X-ray-opaque reference marks (and necessary supporting frames) which can sometimes be invasive for the patient, occlude the radiographic picture, and end up projected outside the imaging sensor area in oblique protocols. Two possible frameworks are envisioned: a spatially shifting X-ray anode around the patient/object and a moving patient that moves/rotates while the imaging system remains fixed. As a proof of concept, experiences with a device under test (DUT), an anthropomorphic phantom and a real brachytherapy session have been carried out. The results show that it is possible to identify common points with a proper level of accuracy and retrieve three-dimensional locations, lengths and shapes with a millimetric level of precision. The presented approach is simple and compatible with both current and legacy widespread diagnostic X-ray imaging deployments and it can represent a good and inexpensive alternative to other radiological modalities like CT.

  19. Investigations into the feasibility of optical-CT 3D dosimetry with minimal use of refractively matched fluids

    Energy Technology Data Exchange (ETDEWEB)

    Chisholm, Kelsey; Miles, Devin [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710 (United States); Rankine, Leith [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Oldham, Mark, E-mail: mark.oldham@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2015-05-15

    Purpose: In optical-CT, the use of a refractively matched polyurethane solid-tank in place of a fluid bath has the potential to greatly increase practical convenience, reduce cost, and possibly improve the efficacy of flood corrections. This work investigates the feasibility of solid-tank optical-CT imaging for 3D dosimetry through computer simulation. Methods: A MATLAB ray-tracing simulation platform, ScanSim, was used to model a parallel-source telecentric optical-CT imaging system through a polyurethane solid-tank containing a central cylindrical hollow into which PRESAGE radiochromic dosimeters can be placed. A small amount of fluid fills the 1–5 mm gap between the dosimeter and the walls of the tank. The use of the solid-tank reduces the required amount of fluid by approximately 97%. To characterize the efficacy of solid-tank, optical-CT scanning simulations investigated sensitivity to refractive index (RI) mismatches between dosimeter, solid-tank, and fluid, for a variety of dosimeter (RI = 1.5–1.47) and fluid (RI = 1.55–1.0) combinations. Efficacy was evaluated through the usable radius (r{sub u}) metric, defined as the fraction of the radius of the dosimeter where measured dose is predicted to be within 2% of the ground truth entered into the simulation. Additional simulations examined the effect of increasing gap size (1–5 mm) between the dosimeter and solid-tank well. The effects of changing the lens tolerance (0.5°–5.0°) were also investigated. Results: As the RI mismatch between the dosimeter and solid-tank increased from 0 to 0.02, the usable radius decreased from 97.6% to 50.2%. The optimal fluid RI decreased nonlinearly from 1.5 to 1.34 as the mismatch increased and was up to 9% lower than the tank. Media mismatches between the dosimeter and solid-tank also exacerbate the effects of changing the gap size, with no easily quantifiable relationship with usable radius. Generally, the optimal fluid RI value increases as gap size increases and

  20. Quality Prediction of Asymmetrically Distorted Stereoscopic 3D Images.

    Science.gov (United States)

    Wang, Jiheng; Rehman, Abdul; Zeng, Kai; Wang, Shiqi; Wang, Zhou

    2015-11-01

    Objective quality assessment of distorted stereoscopic images is a challenging problem, especially when the distortions in the left and right views are asymmetric. Existing studies suggest that simply averaging the quality of the left and right views well predicts the quality of symmetrically distorted stereoscopic images, but generates substantial prediction bias when applied to asymmetrically distorted stereoscopic images. In this paper, we first build a database that contains both single-view and symmetrically and asymmetrically distorted stereoscopic images. We then carry out a subjective test, where we find that the quality prediction bias of the asymmetrically distorted images could lean toward opposite directions (overestimate or underestimate), depending on the distortion types and levels. Our subjective test also suggests that eye dominance effect does not have strong impact on the visual quality decisions of stereoscopic images. Furthermore, we develop an information content and divisive normalization-based pooling scheme that improves upon structural similarity in estimating the quality of single-view images. Finally, we propose a binocular rivalry-inspired multi-scale model to predict the quality of stereoscopic images from that of the single-view images. Our results show that the proposed model, without explicitly identifying image distortion types, successfully eliminates the prediction bias, leading to significantly improved quality prediction of the stereoscopic images.

  1. Reconstruction of 3d Digital Image of Weepingforsythia Pollen

    Science.gov (United States)

    Liu, Dongwu; Chen, Zhiwei; Xu, Hongzhi; Liu, Wenqi; Wang, Lina

    Confocal microscopy, which is a major advance upon normal light microscopy, has been used in a number of scientific fields. By confocal microscopy techniques, cells and tissues can be visualized deeply, and three-dimensional images created. Compared with conventional microscopes, confocal microscope improves the resolution of images by eliminating out-of-focus light. Moreover, confocal microscope has a higher level of sensitivity due to highly sensitive light detectors and the ability to accumulate images captured over time. In present studies, a series of Weeping Forsythia pollen digital images (35 images in total) were acquired with confocal microscope, and the three-dimensional digital image of the pollen reconstructed with confocal microscope. Our results indicate that it's a very easy job to analysis threedimensional digital image of the pollen with confocal microscope and the probe Acridine orange (AO).

  2. Infrared imaging of the polymer 3D-printing process

    Science.gov (United States)

    Dinwiddie, Ralph B.; Kunc, Vlastimil; Lindal, John M.; Post, Brian; Smith, Rachel J.; Love, Lonnie; Duty, Chad E.

    2014-05-01

    Both mid-wave and long-wave IR cameras are used to measure various temperature profiles in thermoplastic parts as they are printed. Two significantly different 3D-printers are used in this study. The first is a small scale commercially available Solidoodle 3 printer, which prints parts with layer thicknesses on the order of 125μm. The second printer used is a "Big Area Additive Manufacturing" (BAAM) 3D-printer developed at Oak Ridge National Laboratory. The BAAM prints parts with a layer thicknesses of 4.06 mm. Of particular interest is the temperature of the previously deposited layer as the new hot layer is about to be extruded onto it. The two layers are expected have a stronger bond if the temperature of the substrate layer is above the glass transition temperature. This paper describes the measurement technique and results for a study of temperature decay and substrate layer temperature for ABS thermoplastic with and without the addition of chopped carbon fibers.

  3. Automatic dental arch detection and panoramic image synthesis from CT images.

    Science.gov (United States)

    Sa-Ing, Vera; Wangkaoom, Kongyot; Thongvigitmanee, Saowapak S

    2013-01-01

    Due to accurate 3D information, computed tomography (CT), especially cone-beam CT or dental CT, has been widely used for diagnosis and treatment planning in dentistry. Axial images acquired from both medical and dental CT scanners can generate synthetic panoramic images sim