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Sample records for angiography fusion images

  1. Fusion of magnetic resonance angiography and magnetic resonance imaging for surgical planning for meningioma. Technical note

    International Nuclear Information System (INIS)

    Kashimura, Hiroshi; Ogasawara, Kuniaki; Arai, Hiroshi

    2008-01-01

    A fusion technique for magnetic resonance (MR) angiography and MR imaging was developed to help assess the peritumoral angioarchitecture during surgical planning for meningioma. Three-dimensional time-of-flight (3D-TOF) and 3D-spoiled gradient recalled (SPGR) datasets were obtained from 10 patients with intracranial meningioma, and fused using newly developed volume registration and visualization software. Maximum intensity projection (MIP) images from 3D-TOF MR angiography and axial SPGR MR imaging were displayed at the same time on the monitor. Selecting a vessel on the real-time MIP image indicated the corresponding points on the axial image automatically. Fusion images showed displacement of the anterior cerebral or middle cerebral artery in 7 patients and encasement of the anterior cerebral arteries in I patient, with no relationship between the main arterial trunk and tumor in 2 patients. Fusion of MR angiography and MR imaging can clarify relationships between the intracranial vasculature and meningioma, and may be helpful for surgical planning for meningioma. (author)

  2. An automatic fuzzy-based multi-temporal brain digital subtraction angiography image fusion algorithm using curvelet transform and content selection strategy.

    Science.gov (United States)

    Momeni, Saba; Pourghassem, Hossein

    2014-08-01

    Recently image fusion has prominent role in medical image processing and is useful to diagnose and treat many diseases. Digital subtraction angiography is one of the most applicable imaging to diagnose brain vascular diseases and radiosurgery of brain. This paper proposes an automatic fuzzy-based multi-temporal fusion algorithm for 2-D digital subtraction angiography images. In this algorithm, for blood vessel map extraction, the valuable frames of brain angiography video are automatically determined to form the digital subtraction angiography images based on a novel definition of vessel dispersion generated by injected contrast material. Our proposed fusion scheme contains different fusion methods for high and low frequency contents based on the coefficient characteristic of wrapping second generation of curvelet transform and a novel content selection strategy. Our proposed content selection strategy is defined based on sample correlation of the curvelet transform coefficients. In our proposed fuzzy-based fusion scheme, the selection of curvelet coefficients are optimized by applying weighted averaging and maximum selection rules for the high frequency coefficients. For low frequency coefficients, the maximum selection rule based on local energy criterion is applied to better visual perception. Our proposed fusion algorithm is evaluated on a perfect brain angiography image dataset consisting of one hundred 2-D internal carotid rotational angiography videos. The obtained results demonstrate the effectiveness and efficiency of our proposed fusion algorithm in comparison with common and basic fusion algorithms.

  3. [Image fusion of gated-SPECT and CT angiography in coronary artery disease. Importance of anatomic-functional correlation].

    Science.gov (United States)

    Nazarena Pizzi, M; Aguadé Bruix, S; Cuéllar Calabria, H; Aliaga, V; Candell Riera, J

    2010-01-01

    A 77-year old patient was admitted for acute coronary syndrome without ST elevation. His risk was stratified using the myocardial perfusion gated SPECT, mild inferior ischemia being observed. Thus, medical therapy was optimized and the patient was discharged. He continued with exertional dyspnea so a coronary CT angiography was performed. It revealed severe lesions in the proximal RCA. SPECT-CT fusion images correlated the myocardial perfusion defect with a posterior descending artery from the RCA, in a co-dominant coronary area. Subsequently, cardiac catheterism was indicated for his treatment. The current use of image fusion studies is limited to patients in whom it is difficult to attribute a perfusion defect to a specific coronary artery. In our patient, the fusion images helped to distinguish between the RCA and the circumflex artery as the culprit artery of ischemia. Copyright © 2010 Elsevier España, S.L. y SEMNIM. All rights reserved.

  4. Fusion imaging of computed tomographic pulmonary angiography and SPECT ventilation/perfusion scintigraphy: initial experience and potential benefit

    International Nuclear Information System (INIS)

    Harris, Benjamin; Bailey, Dale; Roach, Paul; Bailey, Elizabeth; King, Gregory

    2007-01-01

    The objective of this study was to examine the feasibility of fusing ventilation and perfusion data from single-photon emission computed tomography (SPECT) ventilation perfusion (V/Q) scintigraphy together with computed tomographic pulmonary angiography (CTPA) data. We sought to determine the accuracy of this fusion process. In addition, we correlated the findings of this technique with the final clinical diagnosis. Thirty consecutive patients (17 female, 13 male) who had undergone both CTPA and SPECT V/Q scintigraphy during their admission for investigation of potential pulmonary embolism were identified retrospectively. Image datasets from these two modalities were co-registered and fused using commercial software. Accuracy of the fusion process was determined subjectively by correlation between modalities of the anatomical boundaries and co-existent pleuro-parenchymal abnormalities. In all 30 cases, SPECT V/Q images were accurately fused with CTPA images. An automated registration algorithm was sufficient alone in 23 cases (77%). Additional linear z-axis scaling was applied in seven cases. There was accurate topographical co-localisation of vascular, parenchymal and pleural disease on the fused images. Nine patients who had positive CTPA performed as an initial investigation had co-localised perfusion defects on the subsequent fused CTPA/SPECT images. Three of the 11 V/Q scans initially reported as intermediate could be reinterpreted as low probability owing to co-localisation of defects with parenchymal or pleural pathology. Accurate fusion of SPECT V/Q scintigraphy to CTPA images is possible. This technique may be clinically useful in patients who have non-diagnostic initial investigations or in whom corroborative imaging is sought. (orig.)

  5. Relation between lung perfusion defects and intravascular clots in acute pulmonary thromboembolism: assessment with breath-hold SPECT-CT pulmonary angiography fusion images.

    Science.gov (United States)

    Suga, Kazuyoshi; Yasuhiko, Kawakami; Iwanaga, Hideyuki; Tokuda, Osamu; Matsunaga, Naofumi

    2008-09-01

    The relation between lung perfusion defects and intravascular clots in acute pulmonary thromboembolism (PTE) was comprehensively assessed on deep-inspiratory breath-hold (DIBrH) perfusion SPECT-computed tomographic pulmonary angiography (CTPA) fusion images. Subjects were 34 acute PTE patients, who had successfully performed DIBrH perfusion SPECT using a dual-headed SPECT and a respiratory tracking system. Automated DIBrH SPECT-CTPA fusion images were used to assess the relation between lung perfusion defects and intravascular clots detected by CTPA. DIBrH SPECT visualized 175 lobar/segmental or subsegmental defects in 34 patients, and CTPA visualized 61 intravascular clots at variable locations in 30 (88%) patients, but no clots in four (12%) patients. In 30 patients with clots, the fusion images confirmed that 69 (41%) perfusion defects (20 segmental, 45 subsegmental and 4 lobar defects) of total 166 defects were located in lung territories without clots, although the remaining 97 (58%) defects were located in lung territories with clots. Perfusion defect was absent in lung territories with clots (one lobar branch and three segmental branches) in four (12%) of these patients. In four patients without clots, nine perfusion defects including four segmental ones were present. Because of unexpected dissociation between intravascular clots and lung perfusion defects, the present fusion images will be a useful adjunct to CTPA in the diagnosis of acute PTE.

  6. Fusion of CT coronary angiography and whole-heart dynamic 3D cardiac MR perfusion: building a framework for comprehensive cardiac imaging.

    Science.gov (United States)

    von Spiczak, Jochen; Manka, Robert; Gotschy, Alexander; Oebel, Sabrina; Kozerke, Sebastian; Hamada, Sandra; Alkadhi, Hatem

    2018-04-01

    The purpose of this work was to develop a framework for 3D fusion of CT coronary angiography (CTCA) and whole-heart dynamic 3D cardiac magnetic resonance perfusion (3D-CMR-Perf) image data-correlating coronary artery stenoses to stress-induced myocardial perfusion deficits for the assessment of coronary artery disease (CAD). Twenty-three patients who underwent CTCA and 3D-CMR-Perf for various indications were included retrospectively. For CTCA, image quality and coronary diameter stenoses > 50% were documented. For 3D-CMR-Perf, image quality and stress-induced perfusion deficits were noted. A software framework was developed to allow for 3D image fusion of both datasets. Computation steps included: (1) fully automated segmentation of coronary arteries and heart contours from CT; (2) manual segmentation of the left ventricle in 3D-CMR-Perf images; (3) semi-automatic co-registration of CT/CMR datasets; (4) projection of the 3D-CMR-Perf values on the CT left ventricle. 3D fusion analysis was compared to separate inspection of CTCA and 3D-CMR-Perf data. CT and CMR scans resulted in an image quality being rated as good to excellent (mean scores 3.5 ± 0.5 and 3.7 ± 0.4, respectively, scale 1-4). 3D-fusion was feasible in all 23 patients, and perfusion deficits could be correlated to culprit coronary lesions in all but one case (22/23 = 96%). Compared to separate analysis of CT and CMR data, coronary supply territories of 3D-CMR-Perf perfusion deficits were refined in two cases (2/23 = 9%), and the relevance of stenoses in CTCA was re-judged in four cases (4/23 = 17%). In conclusion, 3D fusion of CTCA/3D-CMR-Perf facilitates anatomic correlation of coronary lesions and stress-induced myocardial perfusion deficits thereby helping to refine diagnostic assessment of CAD.

  7. Remote sensing image fusion

    CERN Document Server

    Alparone, Luciano; Baronti, Stefano; Garzelli, Andrea

    2015-01-01

    A synthesis of more than ten years of experience, Remote Sensing Image Fusion covers methods specifically designed for remote sensing imagery. The authors supply a comprehensive classification system and rigorous mathematical description of advanced and state-of-the-art methods for pansharpening of multispectral images, fusion of hyperspectral and panchromatic images, and fusion of data from heterogeneous sensors such as optical and synthetic aperture radar (SAR) images and integration of thermal and visible/near-infrared images. They also explore new trends of signal/image processing, such as

  8. Investigations of image fusion

    Science.gov (United States)

    Zhang, Zhong

    1999-12-01

    The objective of image fusion is to combine information from multiple images of the same scene. The result of image fusion is a single image which is more suitable for the purpose of human visual perception or further image processing tasks. In this thesis, a region-based fusion algorithm using the wavelet transform is proposed. The identification of important features in each image, such as edges and regions of interest, are used to guide the fusion process. The idea of multiscale grouping is also introduced and a generic image fusion framework based on multiscale decomposition is studied. The framework includes all of the existing multiscale-decomposition- based fusion approaches we found in the literature which did not assume a statistical model for the source images. Comparisons indicate that our framework includes some new approaches which outperform the existing approaches for the cases we consider. Registration must precede our fusion algorithms. So we proposed a hybrid scheme which uses both feature-based and intensity-based methods. The idea of robust estimation of optical flow from time- varying images is employed with a coarse-to-fine multi- resolution approach and feature-based registration to overcome some of the limitations of the intensity-based schemes. Experiments show that this approach is robust and efficient. Assessing image fusion performance in a real application is a complicated issue. In this dissertation, a mixture probability density function model is used in conjunction with the Expectation- Maximization algorithm to model histograms of edge intensity. Some new techniques are proposed for estimating the quality of a noisy image of a natural scene. Such quality measures can be used to guide the fusion. Finally, we study fusion of images obtained from several copies of a new type of camera developed for video surveillance. Our techniques increase the capability and reliability of the surveillance system and provide an easy way to obtain 3-D

  9. Imaging of the digital arteries: Digital subtraction angiography versus conventional angiography

    International Nuclear Information System (INIS)

    Menanteau, B.P.; Treutenaere, J.M.; Marcus, C.; Ladam, V.; Gausserand, F.

    1986-01-01

    The authors report their experience with the use of digital subtraction angiography (DSA) and conventional angiography of the hand. Of the 95 patients in the study group, 80 underwent conventional angiography and 15 underwent DSA. They analyzed the studies with regard to the type and amount of contrast agent used, the number of radiographs needed, and the diagnostic quality of the images. Conventional angiography often requires general anesthesia, magnification, and pharmaco-angiographic techniques to improve the image-based diagnosis. In comparison with conventional angiography, intraarterial DSA is characterized by improved contrast sensitivity and inferior spatial resolution. However, DSA provides images as acceptable as those of conventional angiography. Smaller catheters can be used, and the examination is performed under local anesthesia. The authors conclude that intraarterial DSA is now the technique of choice for examining patients with chronic ischemia of the hand

  10. [Image fusion in medical radiology].

    Science.gov (United States)

    Burger, C

    1996-07-20

    Image fusion supports the correlation between images of two or more studies of the same organ. First, the effect of differing geometries during image acquisitions, such as a head tilt, is compensated for. As a consequence, congruent images can easily be obtained. Instead of merely putting them side by side in a static manner and burdening the radiologist with the whole correlation task, image fusion supports him with interactive visualization techniques. This is especially worthwhile for small lesions as they can be more precisely located. Image fusion is feasible today. Easy and robust techniques are readily available, and furthermore DICOM, a rapidly evolving data exchange standard, diminishes the once severe compatibility problems for image data originating from systems of different manufacturers. However, the current solutions for image fusion are not yet established enough for a high throughput of fusion studies. Thus, for the time being image fusion is most appropriately confined to clinical research studies.

  11. Multispectral analytical image fusion

    International Nuclear Information System (INIS)

    Stubbings, T.C.

    2000-04-01

    With new and advanced analytical imaging methods emerging, the limits of physical analysis capabilities and furthermore of data acquisition quantities are constantly pushed, claiming high demands to the field of scientific data processing and visualisation. Physical analysis methods like Secondary Ion Mass Spectrometry (SIMS) or Auger Electron Spectroscopy (AES) and others are capable of delivering high-resolution multispectral two-dimensional and three-dimensional image data; usually this multispectral data is available in form of n separate image files with each showing one element or other singular aspect of the sample. There is high need for digital image processing methods enabling the analytical scientist, confronted with such amounts of data routinely, to get rapid insight into the composition of the sample examined, to filter the relevant data and to integrate the information of numerous separate multispectral images to get the complete picture. Sophisticated image processing methods like classification and fusion provide possible solution approaches to this challenge. Classification is a treatment by multivariate statistical means in order to extract analytical information. Image fusion on the other hand denotes a process where images obtained from various sensors or at different moments of time are combined together to provide a more complete picture of a scene or object under investigation. Both techniques are important for the task of information extraction and integration and often one technique depends on the other. Therefore overall aim of this thesis is to evaluate the possibilities of both techniques regarding the task of analytical image processing and to find solutions for the integration and condensation of multispectral analytical image data in order to facilitate the interpretation of the enormous amounts of data routinely acquired by modern physical analysis instruments. (author)

  12. Myocardial perfusion imaging by digital subtraction angiography

    International Nuclear Information System (INIS)

    Kadowaki, Hiroyuki; Ishikawa, Kinji; Ogai, Toshihiro; Katori, Ryo

    1986-01-01

    Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; 1) at the R wave of the electrocardiogram, 2) 100 msec before the R wave, and 3) 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery. In all patients with anterior myocardial infarction, low perfusion was observed at the infarcted portion compared to the non-infarcted myocardium. In patients with inferior myocardial infarction, this low perfusion area was not observed because right coronary angiography was not subjected to DSA in this study. (J.P.N.)

  13. Correlation of angiography and MR imaging in cerebral vasculitis

    International Nuclear Information System (INIS)

    Cloft, H.J.; Phillips, C.D.; Dix, J.E.; McNulty, B.C.; Kallmes, D.F.; Zagardo, M.T.

    1999-01-01

    Purpose: MR imaging and cerebral angiography were correlated in patients with primary angiitis of the central nervous system (PACNS) to assess the relative roles of these imaging modalities in the diagnosis. Material and Methods: In 9 patients, MR imaging and angiography were compared with regard to the relative involvement of each major vascular territory. Vascular territories assessed were the anterior, middle, and posterior cerebral arteries, and the posterior fossa. Results: All patients had angiographic findings consistent with vasculitis in multiple vascular territories. MR findings ranged from normal to diffusely abnormal. One patient had a completely normal MR investigation. Of 50 territories affected by vasculitis on angiography, 17 (34%) were normal on MR. Conclusion: Relative to cerebral angiography, MR imaging is a poor indicator of the presence or absence of PACNS. Angiography is indicated when clinical suspicion of PACNS is strong, regardless of the findings on MR. (orig.)

  14. [Myocardial perfusion imaging by digital subtraction angiography].

    Science.gov (United States)

    Kadowaki, H; Ishikawa, K; Ogai, T; Katori, R

    1986-03-01

    Several methods of digital subtraction angiography (DSA) were compared to determine which could better visualize regional myocardial perfusion using coronary angiography in seven patients with myocardial infarction, two with angina pectoris and five with normal coronary arteries. Satisfactory DSA was judged to be achieved if the shape of the heart on the mask film was identical to that on the live film and if both films were exactly superimposed. To obtain an identical mask film in the shape of each live film, both films were selected from the following three phases of the cardiac cycle; at the R wave of the electrocardiogram, 100 msec before the R wave, and 200 msec before the R wave. The last two were superior for obtaining mask and live films which were similar in shape, because the cardiac motion in these phases was relatively small. Using these mask and live films, DSA was performed either with the continuous image mode (CI mode) or the time interval difference mode (TID mode). The overall perfusion of contrast medium through the artery to the vein was adequately visualized using the CI mode. Passage of contrast medium through the artery, capillary and vein was visualized at each phase using TID mode. Subtracted images were displayed and photographed, and the density of the contrast medium was adequate to display contour lines as in a relief map. Using this DSA, it was found that regional perfusion of the contrast medium was not always uniform in normal subjects, depending on the typography of the coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Fusion of CT Angiography or MR Angiography with Unenhanced CBCT and Fluoroscopy Guidance in Endovascular Treatments of Aorto-Iliac Steno-Occlusion: Technical Note on a Preliminary Experience

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    Ierardi, Anna Maria; Duka, Ejona [University of Insubria, Interventional Radiology, Department of Radiology (Italy); Radaelli, Alessandro [Philips Healthcare (Netherlands); Rivolta, Nicola; Piffaretti, Gabriele [University of Insubria, Vascular Surgery Department (Italy); Carrafiello, Gianpaolo, E-mail: gcarraf@gmail.com [University of Insubria, Interventional Radiology, Department of Radiology (Italy)

    2016-01-15

    AimTo evaluate the feasibility of image fusion (IF) of pre-procedural arterial-phase CT angiography or MR angiography with intra-procedural fluoroscopy for road-mapping in endovascular treatment of aorto-iliac steno-occlusive disease.Materials and MethodsBetween September and November, 2014, we prospectively evaluated 5 patients with chronic aorto-iliac steno-occlusive disease, who underwent endovascular treatment in the angiography suite. Fusion image road-mapping was performed using angiographic phase CT images or MR images acquired before and intra-procedural unenhanced cone-beam CT. Radiation dose of the procedure, volume of intra-procedural iodinated contrast medium, fluoroscopy time, and overall procedural time were recorded. Reasons for potential fusion imaging inaccuracies were also evaluated.ResultsImage co-registration and fusion guidance were feasible in all procedures. Mean radiation dose of the procedure was 60.21 Gycm2 (range 55.02–63.75 Gycm2). The mean total procedure time was 32.2 min (range 27–38 min). The mean fluoroscopy time was 12 min and 3 s. The mean procedural iodinated contrast material dose was 24 mL (range 20–40 mL).ConclusionsIF gives Interventional Radiologists the opportunity to use new technologies in order to improve outcomes with a significant reduction of contrast media administration.

  16. Fusion of CT Angiography or MR Angiography with Unenhanced CBCT and Fluoroscopy Guidance in Endovascular Treatments of Aorto-Iliac Steno-Occlusion: Technical Note on a Preliminary Experience

    International Nuclear Information System (INIS)

    Ierardi, Anna Maria; Duka, Ejona; Radaelli, Alessandro; Rivolta, Nicola; Piffaretti, Gabriele; Carrafiello, Gianpaolo

    2016-01-01

    AimTo evaluate the feasibility of image fusion (IF) of pre-procedural arterial-phase CT angiography or MR angiography with intra-procedural fluoroscopy for road-mapping in endovascular treatment of aorto-iliac steno-occlusive disease.Materials and MethodsBetween September and November, 2014, we prospectively evaluated 5 patients with chronic aorto-iliac steno-occlusive disease, who underwent endovascular treatment in the angiography suite. Fusion image road-mapping was performed using angiographic phase CT images or MR images acquired before and intra-procedural unenhanced cone-beam CT. Radiation dose of the procedure, volume of intra-procedural iodinated contrast medium, fluoroscopy time, and overall procedural time were recorded. Reasons for potential fusion imaging inaccuracies were also evaluated.ResultsImage co-registration and fusion guidance were feasible in all procedures. Mean radiation dose of the procedure was 60.21 Gycm2 (range 55.02–63.75 Gycm2). The mean total procedure time was 32.2 min (range 27–38 min). The mean fluoroscopy time was 12 min and 3 s. The mean procedural iodinated contrast material dose was 24 mL (range 20–40 mL).ConclusionsIF gives Interventional Radiologists the opportunity to use new technologies in order to improve outcomes with a significant reduction of contrast media administration

  17. Fusion Imaging for Procedural Guidance.

    Science.gov (United States)

    Wiley, Brandon M; Eleid, Mackram F; Thaden, Jeremy J

    2018-05-01

    The field of percutaneous structural heart interventions has grown tremendously in recent years. This growth has fueled the development of new imaging protocols and technologies in parallel to help facilitate these minimally-invasive procedures. Fusion imaging is an exciting new technology that combines the strength of 2 imaging modalities and has the potential to improve procedural planning and the safety of many commonly performed transcatheter procedures. In this review we discuss the basic concepts of fusion imaging along with the relative strengths and weaknesses of static vs dynamic fusion imaging modalities. This review will focus primarily on echocardiographic-fluoroscopic fusion imaging and its application in commonly performed transcatheter structural heart procedures. Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  18. Quantitative myocardial perfusion PET combined with coronary anatomy derived from CT angiography. Validation of a new fusion and visualisation software

    International Nuclear Information System (INIS)

    Fricke, Harald; Weise, Reiner; Burchert, Wolfgang; Fricke, Eva; Elsner, Andreas; Bolte, Matthias; Domik, Gitta; Hoff, Joerg van den

    2009-01-01

    Aim: Dynamic perfusion PET offers a clinical relevant advantage over myocardial perfusion scintigraphy due to its ability to measure myocardial blood flow quantitatively. This leads to an improved detection of multivessel disease and the possibility to assess not only the culprit lesion but lower grade stenoses as well. For appropriate revascularization, perfusion defects must be matched to coronary lesions. It has been shown that image fusion of morphological and functional images is superior to side-by-side analysis. Still, software for quantitative perfusion PET combined with CT angiography is rare. In this paper we present a new software tool for image fusion and visualization of quantitative perfusion PET and coronary morphology derived from CT angiography. Methods: In our software, a PET uptake image is used for manual co-registration. Co-registration results are then applied to the functional data derived from compartment modelling. To evaluate the reproducibility of the manual co-registration, we calculated the deviation between a series of manual co-registrations performed on nine pairs of unregistered PET and CT datasets by five trained participants. Two dimensional transfer functions were used to highlight the coronary arteries from the CT study in the combined data sets. Results: The average Euclidian distances for three references points were between 3.7 and 4.1 mm. The maximum distance was 10.6 mm. By the use of the two dimensional transfer functions, coronary anatomy could be easily visualised either by user-interaction or automatically by use of neuronal networks. Conclusions: With this approach it is possible to combine quantitative perfusion PET with coronary anatomy derived from CT angiography. Our first experiences indicate that manual image fusion with our tool is reproducible and that visualisation of the combined datasets is achieved within short time. (orig.)

  19. Real-time fusion of coronary CT angiography with x-ray fluoroscopy during chronic total occlusion PCI.

    Science.gov (United States)

    Ghoshhajra, Brian B; Takx, Richard A P; Stone, Luke L; Girard, Erin E; Brilakis, Emmanouil S; Lombardi, William L; Yeh, Robert W; Jaffer, Farouc A

    2017-06-01

    The purpose of this study was to demonstrate the feasibility of real-time fusion of coronary computed tomography angiography (CTA) centreline and arterial wall calcification with x-ray fluoroscopy during chronic total occlusion (CTO) percutaneous coronary intervention (PCI). Patients undergoing CTO PCI were prospectively enrolled. Pre-procedural CT scans were integrated with conventional coronary fluoroscopy using prototype software. We enrolled 24 patients who underwent CTO PCI using the prototype CT fusion software, and 24 consecutive CTO PCI patients without CT guidance served as a control group. Mean age was 66 ± 11 years, and 43/48 patients were men. Real-time CTA fusion during CTO PCI provided additional information regarding coronary arterial calcification and tortuosity that generated new insights into antegrade wiring, antegrade dissection/reentry, and retrograde wiring during CTO PCI. Overall CTO success rates and procedural outcomes remained similar between the two groups, despite a trend toward higher complexity in the fusion CTA group. This study demonstrates that real-time automated co-registration of coronary CTA centreline and calcification onto live fluoroscopic images is feasible and provides new insights into CTO PCI, and in particular, antegrade dissection reentry-based CTO PCI. • Real-time semi-automated fusion of CTA/fluoroscopy is feasible during CTO PCI. • CTA fusion data can be toggled on/off as desired during CTO PCI • Real-time CT calcium and centreline overlay could benefit antegrade dissection/reentry-based CTO PCI.

  20. 3D Image Fusion to Localise Intercostal Arteries During TEVAR

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    G. Koutouzi

    Full Text Available Purpose: Preservation of intercostal arteries during thoracic aortic procedures reduces the risk of post-operative paraparesis. The origins of the intercostal arteries are visible on pre-operative computed tomography angiography (CTA, but rarely on intra-operative angiography. The purpose of this report is to suggest an image fusion technique for intra-operative localisation of the intercostal arteries during thoracic endovascular repair (TEVAR. Technique: The ostia of the intercostal arteries are identified and manually marked with rings on the pre-operative CTA. The optimal distal landing site in the descending aorta is determined and marked, allowing enough length for an adequate seal and attachment without covering more intercostal arteries than necessary. After 3D/3D fusion of the pre-operative CTA with an intra-operative cone-beam CT (CBCT, the markings are overlaid on the live fluoroscopy screen for guidance. The accuracy of the overlay is confirmed with digital subtraction angiography (DSA and the overlay is adjusted when needed. Stent graft deployment is guided by the markings. The initial experience of this technique in seven patients is presented. Results: 3D image fusion was feasible in all cases. Follow-up CTA after 1 month revealed that all intercostal arteries planned for preservation, were patent. None of the patients developed signs of spinal cord ischaemia. Conclusion: 3D image fusion can be used to localise the intercostal arteries during TEVAR. This may preserve some intercostal arteries and reduce the risk of post-operative spinal cord ischaemia. Keywords: TEVAR, Intercostal artery, Spinal cord ischaemia, 3D image fusion, Image guidance, Cone-beam CT

  1. Angiography

    International Nuclear Information System (INIS)

    Grinnell, V.S.; Mehringer, C.M.; Hieshima, G.B.

    1987-01-01

    The history of angiography is short, with its centennial approaching. A very brief review of milestones begins with the discovery of x-rays in 1895. Only a few months later contrast agents too toxic for human use were being injected into cadavers, severed limbs, and animals. The next major developments came in the late 1970s when percutaneous translumbar aortography and cerebral angiography were described. Contrast agents were now less toxic, and clinically useful angiography was a reality. In 1953 a technique for percutaneous vascular catheterization which formed the basis of many catheterization techniques to follow was described. In the 1970s the development of less invasive diagnostic methods such as computed tomography and diagnostic ultrasound decreased the indications for angiography, but newer interventional techniques such as embolization therapy and angioplasty have taken up the slack. Angiography remains the most important way to demonstrate vascular diseases graphically. Specific techniques such as angioplasty and digital subtraction angiography will be dealt with in other chapters. The authors hope to provide an overview of major areas of angiographic utilization. The basic techniques of arterial puncture and catheterization have been well described elsewhere

  2. MR imaging and MR angiography in popliteal artery entrapment syndrome

    International Nuclear Information System (INIS)

    Atilla, S.; Akpek, S.; Yuecel, C.; Tali, E.T.; Isik, S.; Ilgit, E.T.

    1998-01-01

    Popliteal artery entrapment (PAE) syndrome is an uncommon congenital anomaly seen in young adults causing ischemic symptoms in the lower extremities. It is the result of various types of anomalous relationships between the popliteal artery and the neighboring muscular structures. The purpose of this study was to define the role of MR imaging combined with MR angiography in the diagnosis of PAE cases. Four cases with segmental occlusion and medial displacement of popliteal artery in digital subtraction angiography (DSA) examinations were diagnosed as PAE syndrome by MR imaging and MR angiography. The DSA and MRA images are compared. All of the cases showed various degrees of abnormal intercondylar insertion of the medial head of the gastrocnemius muscle. The MR images showed detailed anatomy of the region revealing the cause of the arterial entrapment. Subclassification of the cases were done and fat tissue filling the normal localization of the muscle was evaluated. The DSA and MRA images demonstrated the length and localization of the occluded segment and collateral vascular developments equally. It is concluded that angiographic evaluation alone in PAE syndrome might result in overlooking the underlying cause of the arterial occlusion, which in turn leads to unsuccessful therapy procedures such as balloon angioplasty. Magnetic resonance imaging combined with MR angiography demonstrates both the vascular anatomy and the variations in the muscular structures in the popliteal fossa successfully, and this combination seems to be the most effective way of evaluating young adults with ischemic symptoms suggesting PAE syndrome. (orig.)

  3. Vascular imaging with spiral CT. The way to CY angiography

    International Nuclear Information System (INIS)

    Prokop, M.; Schaefer, C.; Kalender, W.A.; Polacin, A.; Galanski, M.

    1993-01-01

    Spiral CT is a technique that allows for high-quality two-dimensional angiographic projections and 3D imaging of vascular structures. The authors present the technical and methodological principles of the technique, including scan parameters and parameters of contrast application for various clinical imaging tasks. They present their experience with over 150 clinical cases using spiral CT angiography. Suitable applications of this technique include cogenital anomalies, aneurysms, dissections, stenoses, thrombi and vascular tumor involvement. Given a problem-adapted examination technique, pathologic changes in vessels of as little as 2 mm can be visualized. In some cases with complex vascular anatomy, spiral CT angiography can be superior to arterial angiography. (orig.) [de

  4. A study of transverse image reconstruction with digital subtraction angiography

    International Nuclear Information System (INIS)

    Sakamoto, Kiyoshi; Kotoura, Noriko; Terasawa, Yuuji; Oda, Masahiko; Gotou, Hiroshi; Nasada, Toshiya; Tanooka, Masao

    1995-01-01

    For digital subtraction angiography (DSA) with C-type equipment, it is possible to radiate an X-ray during rotation and to collect data at different angular settings. We tried to reconstruct transverse image from data obtained by scanning DSA images at different angular settings. 88 projection data were obtained by rotating the object at 180deg during radiation. Reconstruction was made using the convolution method with pixel value distribution for each projection. Similarly, the image quality of the reconstructed images were compared with the unsubtracted and subtracted ones. In case a part object was outside the calculating region, artifacts were generally produced. However, the artifacts were reduced by subtracting the background from the image. In addition, the cupping phenomenon caused by beam hardening was relaxed and high-quality imaging could be achieved. This method will become even more effective, if we will use it with selective angiography in which the limited area is enhanced. (author)

  5. Acoustic Angiography: A New Imaging Modality for Assessing Microvasculature Architecture

    Directory of Open Access Journals (Sweden)

    Ryan C. Gessner

    2013-01-01

    Full Text Available The purpose of this paper is to provide the biomedical imaging community with details of a new high resolution contrast imaging approach referred to as “acoustic angiography.” Through the use of dual-frequency ultrasound transducer technology, images acquired with this approach possess both high resolution and a high contrast-to-tissue ratio, which enables the visualization of microvascular architecture without significant contribution from background tissues. Additionally, volumetric vessel-tissue integration can be visualized by using b-mode overlays acquired with the same probe. We present a brief technical overview of how the images are acquired, followed by several examples of images of both healthy and diseased tissue volumes. 3D images from alternate modalities often used in preclinical imaging, contrast-enhanced micro-CT and photoacoustics, are also included to provide a perspective on how acoustic angiography has qualitatively similar capabilities to these other techniques. These preliminary images provide visually compelling evidence to suggest that acoustic angiography may serve as a powerful new tool in preclinical and future clinical imaging.

  6. Quantification of image persistence in a digital angiography system

    International Nuclear Information System (INIS)

    Okkalides, D.P.; Raptou, P.D.

    1993-01-01

    Image persistence, as a characteristic of video imaging systems affecting the quality of fast moving fluoroscopic images, is shown to vary considerably. A simple quantitative method for measuring image persistence in a digital angiography system is presented, together with a series of image intensifier exposure-response curves. For the Saticon tube, used with the Siemens 3VA Digitron, it was found that persistence increased for low exposure rates and may increase to 31% at a 120 ms interval. In addition, a sharp increase in image persistence, from 8.3% to 33%, was observed within 18 months from installation of the system. (author)

  7. Real-time fusion of coronary CT angiography with X-ray fluoroscopy during chronic total occlusion PCI

    Energy Technology Data Exchange (ETDEWEB)

    Ghoshhajra, Brian B.; Takx, Richard A.P. [Harvard Medical School, Cardiac MR PET CT Program, Massachusetts General Hospital, Department of Radiology and Division of Cardiology, Boston, MA (United States); Stone, Luke L.; Yeh, Robert W.; Jaffer, Farouc A. [Harvard Medical School, Cardiac Cathetrization Laboratory, Cardiology Division, Massachusetts General Hospital, Boston, MA (United States); Girard, Erin E. [Siemens Healthcare, Princeton, NJ (United States); Brilakis, Emmanouil S. [Cardiology Division, Dallas VA Medical Center and UT Southwestern Medical Center, Dallas, TX (United States); Lombardi, William L. [University of Washington, Cardiology Division, Seattle, WA (United States)

    2017-06-15

    The purpose of this study was to demonstrate the feasibility of real-time fusion of coronary computed tomography angiography (CTA) centreline and arterial wall calcification with X-ray fluoroscopy during chronic total occlusion (CTO) percutaneous coronary intervention (PCI). Patients undergoing CTO PCI were prospectively enrolled. Pre-procedural CT scans were integrated with conventional coronary fluoroscopy using prototype software. We enrolled 24 patients who underwent CTO PCI using the prototype CT fusion software, and 24 consecutive CTO PCI patients without CT guidance served as a control group. Mean age was 66 ± 11 years, and 43/48 patients were men. Real-time CTA fusion during CTO PCI provided additional information regarding coronary arterial calcification and tortuosity that generated new insights into antegrade wiring, antegrade dissection/reentry, and retrograde wiring during CTO PCI. Overall CTO success rates and procedural outcomes remained similar between the two groups, despite a trend toward higher complexity in the fusion CTA group. This study demonstrates that real-time automated co-registration of coronary CTA centreline and calcification onto live fluoroscopic images is feasible and provides new insights into CTO PCI, and in particular, antegrade dissection reentry-based CTO PCI. (orig.)

  8. Catheter Angiography

    Medline Plus

    Full Text Available ... is performed using: x-rays with catheters computed tomography (CT) magnetic resonance imaging (MRI) In catheter angiography, ... tumor; this is called superselective angiography. Unlike computed tomography (CT) or magnetic resonance (MR) angiography , use of ...

  9. Catheter Angiography

    Medline Plus

    Full Text Available ... is performed using: x-rays with catheters computed tomography (CT) magnetic resonance imaging (MRI) In catheter angiography, a ... tumor; this is called superselective angiography. Unlike computed tomography (CT) or magnetic resonance (MR) angiography , use of a ...

  10. Catheter Angiography

    Medline Plus

    Full Text Available ... using: x-rays with catheters computed tomography (CT) magnetic resonance imaging (MRI) In catheter angiography, a thin plastic ... called superselective angiography. Unlike computed tomography (CT) or magnetic resonance (MR) angiography , use of a catheter makes it ...

  11. Imaging of the bronchial blood flow using RI-angiography

    International Nuclear Information System (INIS)

    Fujii, Tadashige; Hirayama, Jiro; Kanai, Hisakata; Kobayashi, Toshio; Handa, Kenjiro

    1979-01-01

    RI-angiography with sup(99m)TcO 4 - was carried out using a scintillation camera with a digital minicomputer for the purpose of imaging of bronchial blood flow in various lung diseases, and as application of dual radioisotope techniques, other imagings such as tumor imaging with 197 HgCl 2 or 67 Ga-citrate and/or perfusion imaging with sup(99m)Tc-MAA, were performed simultaneously in patients remaining the same position, too. The image as a iso-count map extracted out of the image of 197 HgCl 2 , 67 Ga-citrate or sup(99m)Tc-MAA, was superimposed to the brightness image of RI-angiogram (aortic phase). By these procedures, the image of bronchial blood flow were obtained in some patients with lung cancer, pulmonary tuberculosis, lung abscess, and chronic bronchitis. The dual radioisotope techniques using RI-angiography and the other imaging were useful to make isotope diagnosis of lung diseases more reliable, and the image superimposition methods using RI-angiogram and the image of tumor of perfusion, were useful to improve anatomic orientation of the former. (author)

  12. Identification of arteries and veins in cerebral angiography fluoroscopic images

    Science.gov (United States)

    Andra Tache, Irina

    2017-11-01

    In the present study a new method for pixels tagging into arteries and veins classes from temporal cerebral angiography is presented. This need comes from the neurosurgeon who is evaluating the fluoroscopic angiography and the magnetic resonance images from the brain in order to locate the fistula of the patients who suffer from arterio-venous malformation. The method includes the elimination of the background pixels from a previous segmentation and the generation of the time intensity curves for each remaining pixel. The later undergo signal processing in order to extract the characteristic parameters needed for applying the k-means clustering algorithm. Some of the parameters are: the phase and the maximum amplitude extracted from the Fourier transform, the standard deviation and the mean value. The tagged classes are represented into images which then are re-classified by an expert into artery and vein pixels.

  13. Image quality in coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Precht, Helle; Gerke, Oke; Thygesen, Jesper

    2018-01-01

    Background Computed tomography (CT) technology is rapidly evolving and software solution developed to optimize image quality and/or lower radiation dose. Purpose To investigate the influence of adaptive statistical iterative reconstruction (ASIR) at different radiation doses in coronary CT...

  14. Catheter Angiography

    Medline Plus

    Full Text Available ... story about radiology? Share your patient story here Images × Image Gallery Interventional radiologist performing an angiography exam View ... ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Catheter Angiography Sponsored by Please note ...

  15. Visualization of intracranial vessel anatomy using high resolution MRI and a simple image fusion technique

    International Nuclear Information System (INIS)

    Nasel, C.

    2005-01-01

    A new technique for fusion and 3D viewing of high resolution magnetic resonance (MR) angiography and morphological MR sequences is reported. Scanning and image fusion was possible within 20 min on a standard 1.5 T MR-scanner. The procedure was successfully performed in 10 consecutive cases with excellent visualization of wall and luminal aspects of the intracranial segments of the internal carotid artery, the vertebrobasilar system and the anterior, middle and posterior cerebral artery

  16. Visualization of intracranial vessel anatomy using high resolution MRI and a simple image fusion technique

    Energy Technology Data Exchange (ETDEWEB)

    Nasel, C. [Division of Neuroradiology, Department of Radiology, Medical University of Vienna, Waehringerguertel 18-20, A-1090 Vienna (Austria)]. E-mail: christian.nasel@perfusion.at

    2005-04-01

    A new technique for fusion and 3D viewing of high resolution magnetic resonance (MR) angiography and morphological MR sequences is reported. Scanning and image fusion was possible within 20 min on a standard 1.5 T MR-scanner. The procedure was successfully performed in 10 consecutive cases with excellent visualization of wall and luminal aspects of the intracranial segments of the internal carotid artery, the vertebrobasilar system and the anterior, middle and posterior cerebral artery.

  17. Simultaneous maximal exercise radionuclide angiography and thallium stress perfusion imaging

    International Nuclear Information System (INIS)

    Narahara, K.A.; Mena, I.; Maublant, J.C.; Brizendine, M.; Criley, J.M.

    1984-01-01

    Gold-195m is a new ultra-short-lived radionuclide that can be used for cardiac studies. Accurate, reproducible ejection fraction and ventricular wall motion studies can be obtained from first-transit angiography using commercially available imaging and image-processing equipment. The short half-life of gold-195m (30.5 seconds) makes simultaneous dual isotope imaging possible and substantially reduces the radiation exposure from the isotope angiography. The feasibility and possible benefits of performing dual radionuclide studies were evaluated during a single exercise stress test in 24 subjects with known coronary artery disease (CAD) and in 20 normal volunteers. High-quality first-transit angiograms were obtained in all subjects. An 83% sensitivity and 95% specificity for detecting CAD with thallium-201 imaging was noted in this investigation, suggesting that its diagnostic accuracy was not altered by simultaneous dual isotone imaging. When segmental left ventricular (LV) wall motion was compared with thallium-201 perfusion imaging, divergent results were noted in 15 of 44 subjects. An analysis of the ejection fraction (EF) results at rest and stress provided additional information that could be useful in assessing the clinical significance of such differences in segmental wall motion and perfusion. Simultaneous dual isotope imaging appears to be appropriate for situations in which both LV perfusion and function require evaluation. The use of gold-195m allows such information to be obtained from a single exercise test and can thereby reduce the cost and time required for noninvasive evaluations of patients for CAD

  18. CT reconstruction and MRI fusion of 3D rotational angiography in the evaluation of pediatric cerebrovascular lesions

    Energy Technology Data Exchange (ETDEWEB)

    Muthusami, Prakash; Rea, Vanessa; Shroff, Manohar [The Hospital for Sick Children, Pediatric Neuroradiology and Image Guided Therapy, Department of Diagnostic Imaging, Toronto, ON (Canada); Shkumat, Nicholas [The Hospital for Sick Children, Medical Physics, Department of Diagnostic Imaging, Toronto, ON (Canada); Chiu, Albert H. [Institute of Neurological Sciences, Prince of Wales Hospital, Department of Interventional Neuroradiology, Randwick, NSW (Australia)

    2017-06-15

    Complex neurovascular lesions in children require precise anatomic understanding for treatment planning. Although 3DRA is commonly employed for volumetric reformation in neurointerventional procedures, the ability to reconstruct this data into CT-like images (3DRA-CT) is not widely utilized. This study demonstrates the feasibility and usefulness of 3DRA-CT and subsequent MRI fusion for problem solving in pediatric neuroangiography. This retrospective study includes 18 3DRA-CT studies in 16 children (age 9.6 ± 3.8 years, range 2-16 years) over 1 year. After biplane 2D-digital subtraction angiography (DSA), 5-second 3DRA was performed with selective vessel injection either with or without subtraction. Images were reconstructed into CT sections which were post-processed to generate multiplanar reformation (MPR) and maximum intensity projection (MIP) images. Fusion was performed with 3D T1 MRI images to precisely demonstrate neurovascular relationships. Quantitative radiation metrics were extracted and compared against those for the entire examination and for corresponding biplane 2D-DSA acquisitions. In all 18 cases, the 3DRA procedure and MRI fusion were technically successful and provided clinically useful information relevant to management. The unsubtracted and subtracted 3DRA acquisitions were measured to deliver 5.9 and 132.2%, respectively, of the mean radiation dose of corresponding biplane 2D-DSA acquisitions and contributed 1.2 and 12.5%, respectively, to the total procedure dose. Lower radiation doses, high spatial resolution, and multiplanar reformatting capability make 3DRA-CT a useful adjunct to evaluate neurovascular lesions in children. Fusing 3DRA-CT data with MRI is an additional capability that can further enhance diagnostic information. (orig.)

  19. Incidence of ischemic lesions in diffusion-weighted imaging after transbrachial digital subtraction angiography

    International Nuclear Information System (INIS)

    Aschenbach, R.; Majeed, A.; Eger, C.; Basche, S.; Kerl, J.M.; Vogl, T.J.

    2008-01-01

    Purpose: to evaluate the frequency of ischemia after transbrachial digital subtraction angiography under ambulant conditions using diffusion-weighted imaging. Materials and methods: 200 patients were included in a prospective study design and received transbrachial digital subtraction angiography under ambulant conditions. Before and after digital subtraction angiography, diffusion-weighted imaging of the brain was performed. Results: in our study population no new lesions were found in diffusion-weighted imaging after digital subtraction angiography during the 3-hour window after angiography. One new lesion was found 3 days after angiography as a late onset complication. Therefore, the frequency of neurological complications is at the level of the confidence interval of 0 - 1.5%. Conclusion: the transbrachial approach under ambulant conditions is a safe method for digital subtraction angiography resulting in a low rate of ischemic lesions in diffusion-weighted imaging. (orig.)

  20. Prognostic value of combined CT angiography and myocardial perfusion imaging versus invasive coronary angiography and nuclear stress perfusion imaging in the prediction of major adverse cardiovascular events

    DEFF Research Database (Denmark)

    Chen, Marcus Y.; Rochitte, Carlos E.; Arbab-Zadeh, Armin

    2017-01-01

    Purpose: To compare the prognostic importance (time to major adverse cardiovascular event [MACE]) of combined computed tomography (CT) angiography and CT myocardial stress perfusion imaging with that of combined invasive coronary angiography (ICA) and stress single photon emission CT myocardial p...

  1. Combined Sparsifying Transforms for Compressive Image Fusion

    Directory of Open Access Journals (Sweden)

    ZHAO, L.

    2013-11-01

    Full Text Available In this paper, we present a new compressive image fusion method based on combined sparsifying transforms. First, the framework of compressive image fusion is introduced briefly. Then, combined sparsifying transforms are presented to enhance the sparsity of images. Finally, a reconstruction algorithm based on the nonlinear conjugate gradient is presented to get the fused image. The simulations demonstrate that by using the combined sparsifying transforms better results can be achieved in terms of both the subjective visual effect and the objective evaluation indexes than using only a single sparsifying transform for compressive image fusion.

  2. Iodine filter imaging system for subtraction angiography using synchrotron radiation

    Science.gov (United States)

    Umetani, K.; Ueda, K.; Takeda, T.; Itai, Y.; Akisada, M.; Nakajima, T.

    1993-11-01

    A new type of real-time imaging system was developed for transvenous coronary angiography. A combination of an iodine filter and a single energy broad-bandwidth X-ray produces two-energy images for the iodine K-edge subtraction technique. X-ray images are sequentially converted to visible images by an X-ray image intensifier. By synchronizing the timing of the movement of the iodine filter into and out of the X-ray beam, two output images of the image intensifier are focused side by side on the photoconductive layer of a camera tube by an oscillating mirror. Both images are read out by electron beam scanning of a 1050-scanning-line video camera within a camera frame time of 66.7 ms. One hundred ninety two pairs of iodine-filtered and non-iodine-filtered images are stored in the frame memory at a rate of 15 pairs/s. In vivo subtracted images of coronary arteries in dogs were obtained in the form of motion pictures.

  3. CBCT-based 3D MRA and angiographic image fusion and MRA image navigation for neuro interventions.

    Science.gov (United States)

    Zhang, Qiang; Zhang, Zhiqiang; Yang, Jiakang; Sun, Qi; Luo, Yongchun; Shan, Tonghui; Zhang, Hao; Han, Jingfeng; Liang, Chunyang; Pan, Wenlong; Gu, Chuanqi; Mao, Gengsheng; Xu, Ruxiang

    2016-08-01

    Digital subtracted angiography (DSA) remains the gold standard for diagnosis of cerebral vascular diseases and provides intraprocedural guidance. This practice involves extensive usage of x-ray and iodinated contrast medium, which can induce side effects. In this study, we examined the accuracy of 3-dimensional (3D) registration of magnetic resonance angiography (MRA) and DSA imaging for cerebral vessels, and tested the feasibility of using preprocedural MRA for real-time guidance during endovascular procedures.Twenty-three patients with suspected intracranial arterial lesions were enrolled. The contrast medium-enhanced 3D DSA of target vessels were acquired in 19 patients during endovascular procedures, and the images were registered with preprocedural MRA for fusion accuracy evaluation. Low-dose noncontrasted 3D angiography of the skull was performed in the other 4 patients, and registered with the MRA. The MRA was overlaid afterwards with 2D live fluoroscopy to guide endovascular procedures.The 3D registration of the MRA and angiography demonstrated a high accuracy for vessel lesion visualization in all 19 patients examined. Moreover, MRA of the intracranial vessels, registered to the noncontrasted 3D angiography in the 4 patients, provided real-time 3D roadmap to successfully guide the endovascular procedures. Radiation dose to patients and contrast medium usage were shown to be significantly reduced.Three-dimensional MRA and angiography fusion can accurately generate cerebral vasculature images to guide endovascular procedures. The use of the fusion technology could enhance clinical workflow while minimizing contrast medium usage and radiation dose, and hence lowering procedure risks and increasing treatment safety.

  4. Image noise reduction algorithm for digital subtraction angiography: clinical results.

    Science.gov (United States)

    Söderman, Michael; Holmin, Staffan; Andersson, Tommy; Palmgren, Charlotta; Babic, Draženko; Hoornaert, Bart

    2013-11-01

    To test the hypothesis that an image noise reduction algorithm designed for digital subtraction angiography (DSA) in interventional neuroradiology enables a reduction in the patient entrance dose by a factor of 4 while maintaining image quality. This clinical prospective study was approved by the local ethics committee, and all 20 adult patients provided informed consent. DSA was performed with the default reference DSA program, a quarter-dose DSA program with modified acquisition parameters (to reduce patient radiation dose exposure), and a real-time noise-reduction algorithm. Two consecutive biplane DSA data sets were acquired in each patient. The dose-area product (DAP) was calculated for each image and compared. A randomized, blinded, offline reading study was conducted to show noninferiority of the quarter-dose image sets. Overall, 40 samples per treatment group were necessary to acquire 80% power, which was calculated by using a one-sided α level of 2.5%. The mean DAP with the quarter-dose program was 25.3% ± 0.8 of that with the reference program. The median overall image quality scores with the reference program were 9, 13, and 12 for readers 1, 2, and 3, respectively. These scores increased slightly to 12, 15, and 12, respectively, with the quarter-dose program imaging chain. In DSA, a change in technique factors combined with a real-time noise-reduction algorithm will reduce the patient entrance dose by 75%, without a loss of image quality. RSNA, 2013

  5. Spatial relationship between intrahepatic artery and portal vein based on the fusion image of CT-arterial portography (CTAP) and CT-angiography (CTA): New classification for hepatic artery at hepatic hilum and the segmentation of right anterior section of the liver

    International Nuclear Information System (INIS)

    Ibukuro, Kenji; Takeguchi, Takaya; Fukuda, Hozumi; Abe, Shoko; Tobe, Kimiko; Tanaka, Rei; Tagawa, Kazumi

    2012-01-01

    Purpose: To clarify the variations of the intrahepatic artery and portal vein and to verify the proper segmentation for the right anterior section of the liver. Materials and methods: CT during arterial portography and CT angiography were performed on 64-slice multi detector row CT in 147 patients. All images were transferred to a workstation for analysis using multi-image-fusion mode. We investigated the spatial relationship between hepatic artery and portal vein in the right hemiliver and the segmentation of the right anterior hepatic artery and portal vein. Results: The spatial anatomy of right hepatic arteries and portal vein was (1) anterior and posterior hepatic artery run superior and inferior to anterior portal vein, respectively (47.6%), (2) one anterior hepatic artery runs superior to and another one runs inferior to anterior portal vein (15%), (3) anterior and posterior hepatic arteries run superior to anterior portal vein (11.6%), (4) anterior and posterior hepatic arteries run inferior to anterior portal vein (7.5%), and (5) one posterior hepatic artery runs superior to and another one runs inferior to anterior portal vein (6.8%). The combined anatomy of right anterior artery and portal vein with regard to segmentation was classified as (1) dorso-ventral (26.5%), (2) dorso-ventral and inferior (10.9%), (3) multiple (18.4%), and (4) superior and inferior segments (1.4%). Conclusion: There are various types of spatial anatomy of intrahepatic artery and portal vein. The hepatic arteries as well as portal veins of right anterior section of the liver could be divided into dorsal and ventral, not superior and inferior.

  6. Catheter Angiography

    Medline Plus

    Full Text Available ... Z Catheter Angiography Catheter angiography uses a catheter, x-ray imaging guidance and an injection of contrast material ... vessels in the body. Angiography is performed using: x-rays with catheters computed tomography (CT) magnetic resonance imaging ( ...

  7. Catheter Angiography

    Medline Plus

    Full Text Available ... far outweighs the risk. If you have a history of allergy to x-ray contrast material, your ... Angiography (CTA) X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to Catheter Angiography Sponsored ...

  8. Catheter Angiography

    Medline Plus

    Full Text Available ... resonance imaging (MRI) In catheter angiography, a thin plastic tube, called a catheter , is inserted into an ... The catheter used in angiography is a long plastic tube about as thick as a strand of ...

  9. Image fusion tool: Validation by phantom measurements

    International Nuclear Information System (INIS)

    Zander, A.; Geworski, L.; Richter, M.; Ivancevic, V.; Munz, D.L.; Muehler, M.; Ditt, H.

    2002-01-01

    Aim: Validation of a new image fusion tool with regard to handling, application in a clinical environment and fusion precision under different acquisition and registration settings. Methods: The image fusion tool investigated allows fusion of imaging modalities such as PET, CT, MRI. In order to investigate fusion precision, PET and MRI measurements were performed using a cylinder and a body contour-shaped phantom. The cylinder phantom (diameter and length 20 cm each) contained spheres (10 to 40 mm in diameter) which represented 'cold' or 'hot' lesions in PET measurements. The body contour-shaped phantom was equipped with a heart model containing two 'cold' lesions. Measurements were done with and without four external markers placed on the phantoms. The markers were made of plexiglass (2 cm diameter and 1 cm thickness) and contained a Ga-Ge-68 core for PET and Vitamin E for MRI measurements. Comparison of fusion results with and without markers was done visually and by computer assistance. This algorithm was applied to the different fusion parameters and phantoms. Results: Image fusion of PET and MRI data without external markers yielded a measured error of 0 resulting in a shift at the matrix border of 1.5 mm. Conclusion: The image fusion tool investigated allows a precise fusion of PET and MRI data with a translation error acceptable for clinical use. The error is further minimized by using external markers, especially in the case of missing anatomical orientation. Using PET the registration error depends almost only on the low resolution of the data

  10. Image fusion for enhanced forest structural assessment

    CSIR Research Space (South Africa)

    Roberts, JW

    2011-01-01

    Full Text Available This research explores the potential benefits of fusing active and passive medium resolution satellite-borne sensor data for forest structural assessment. Image fusion was applied as a means of retaining disparate data features relevant to modeling...

  11. Fusion of Images from Dissimilar Sensor Systems

    National Research Council Canada - National Science Library

    Chow, Khin

    2004-01-01

    Different sensors exploit different regions of the electromagnetic spectrum; therefore a multi-sensor image fusion system can take full advantage of the complementary capabilities of individual sensors in the suit...

  12. Quantitative image fusion in infrared radiometry

    Science.gov (United States)

    Romm, Iliya; Cukurel, Beni

    2018-05-01

    Towards high-accuracy infrared radiance estimates, measurement practices and processing techniques aimed to achieve quantitative image fusion using a set of multi-exposure images of a static scene are reviewed. The conventional non-uniformity correction technique is extended, as the original is incompatible with quantitative fusion. Recognizing the inherent limitations of even the extended non-uniformity correction, an alternative measurement methodology, which relies on estimates of the detector bias using self-calibration, is developed. Combining data from multi-exposure images, two novel image fusion techniques that ultimately provide high tonal fidelity of a photoquantity are considered: ‘subtract-then-fuse’, which conducts image subtraction in the camera output domain and partially negates the bias frame contribution common to both the dark and scene frames; and ‘fuse-then-subtract’, which reconstructs the bias frame explicitly and conducts image fusion independently for the dark and the scene frames, followed by subtraction in the photoquantity domain. The performances of the different techniques are evaluated for various synthetic and experimental data, identifying the factors contributing to potential degradation of the image quality. The findings reflect the superiority of the ‘fuse-then-subtract’ approach, conducting image fusion via per-pixel nonlinear weighted least squares optimization.

  13. Effects of electrocardiogram gating on CT pulmonary angiography image quality

    International Nuclear Information System (INIS)

    Ardley, Nicholas D.; Lau, Ken K.; Troupis, John M.; Buchan, Kevin; Paul, Eldho

    2014-01-01

    Pulmonary embolism (PE) is the third most common cause of death from cardiovascular disease. Computed-tomographic pulmonary angiography (CTPA) is an accurate and safe test for diagnosing PE. The aim of this retrospective analysis was to evaluate the effects on image quality (IQ) of electrocardiogram (ECG) gating during CTPA. Fifty consecutive patients presenting for CTPA were included in the study. A single acquisition was performed, resulting in two reconstructions: one at 75% of the R–R interval and the other without ECG influence. IQ evaluation was undertaken by two radiologists, focusing on respiratory and cardiac motion, image noise, low-contrast resolution, vessel and lung clarity, contrast media opacification and artefacts. Various regions of the lungs and vasculature were evaluated, and IQ scores were statistically compared. For the ECG-tagged reconstructions, IQ was noted to be better overall with regard to vessel clarity (P<0.05) and cardiac motion (P<0.05), while lung clarity was better only in the left lower zone (P<0.05). IQ was better with regard to image noise (P<0.05) and low-contrast resolution (P<0.05) in the non-ECG-tagged reconstructions. No statistical IQ difference between the two types of reconstruction was noted with regard to respiratory motion, contrast media opacification or presence of artefacts. The two types of reconstruction provide complementary information for evaluating CTPA results.

  14. Fusion of three-dimensional X-ray angiography and three-dimensional echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Rasche, Volker [University of Ulm, Department of Internal Medicine II, Ulm (Germany); Philips Medical Systems, Bothell, WA (United States); Mansour, Moussa; Reddy, Vivek; Singh, Jagmeet P.; Ruskin, Jeremy [Massachusetts General Hospital, Harvard Medical School, Cardiac Arrhythmia Service, Boston, MA (United States); Qureshi, Answer [Massachusetts General Hospital, Harvard Medical School, Echocardiography, Boston, MA (United States); Manzke, Robert; Sokka, Sham [Philips Research North America, Clinical Sites Research, Briacliff Manor, NY (United States)

    2008-03-15

    Cardiovascular intervention guidance requires knowledge of heart function relative to its blood supply or venous drainage. Functional and vascular anatomic data are usually generated on different imaging systems, so fusion of the data is necessary to simultaneously visualize the results for intervention planning and guidance. The objective of this work is to establish the feasibility of fusing volumetric ultrasound (U/S) data with three-dimensional (3D) X-ray imaging data for visualization of cardiac morphology, function and coronary venous drainage. Temporally resolved U/S volume data was registered with the 3D reconstruction of vascular structures derived from X-ray modeling and reconstruction. U/S image registration was obtained by optical tracking fiducial markers with simultaneous X-ray imaging. The proposed technique was applied to phantom data for accuracy assessment of the registration process and to biventricular pacemaker implantation as clinical example. Fusion of U/S data with 3D X-ray reconstruction data produced an RMS registration error below 2 mm. Preliminary clinical feasibility of U/S-derived data synchronously with X-ray derived 3D coronary venography was established. This technique can be applied for fusion of functional U/S data with 3D anatomic X-ray data of the coronary veins during a biventricular pacemaker implantation procedures. (orig.)

  15. Fusion of three-dimensional X-ray angiography and three-dimensional echocardiography

    International Nuclear Information System (INIS)

    Rasche, Volker; Mansour, Moussa; Reddy, Vivek; Singh, Jagmeet P.; Ruskin, Jeremy; Qureshi, Answer; Manzke, Robert; Sokka, Sham

    2008-01-01

    Cardiovascular intervention guidance requires knowledge of heart function relative to its blood supply or venous drainage. Functional and vascular anatomic data are usually generated on different imaging systems, so fusion of the data is necessary to simultaneously visualize the results for intervention planning and guidance. The objective of this work is to establish the feasibility of fusing volumetric ultrasound (U/S) data with three-dimensional (3D) X-ray imaging data for visualization of cardiac morphology, function and coronary venous drainage. Temporally resolved U/S volume data was registered with the 3D reconstruction of vascular structures derived from X-ray modeling and reconstruction. U/S image registration was obtained by optical tracking fiducial markers with simultaneous X-ray imaging. The proposed technique was applied to phantom data for accuracy assessment of the registration process and to biventricular pacemaker implantation as clinical example. Fusion of U/S data with 3D X-ray reconstruction data produced an RMS registration error below 2 mm. Preliminary clinical feasibility of U/S-derived data synchronously with X-ray derived 3D coronary venography was established. This technique can be applied for fusion of functional U/S data with 3D anatomic X-ray data of the coronary veins during a biventricular pacemaker implantation procedures. (orig.)

  16. Image fusion techniques in permanent seed implantation

    Directory of Open Access Journals (Sweden)

    Alfredo Polo

    2010-10-01

    Full Text Available Over the last twenty years major software and hardware developments in brachytherapy treatment planning, intraoperative navigation and dose delivery have been made. Image-guided brachytherapy has emerged as the ultimate conformal radiation therapy, allowing precise dose deposition on small volumes under direct image visualization. In thisprocess imaging plays a central role and novel imaging techniques are being developed (PET, MRI-MRS and power Doppler US imaging are among them, creating a new paradigm (dose-guided brachytherapy, where imaging is used to map the exact coordinates of the tumour cells, and to guide applicator insertion to the correct position. Each of these modalities has limitations providing all of the physical and geometric information required for the brachytherapy workflow.Therefore, image fusion can be used as a solution in order to take full advantage of the information from each modality in treatment planning, intraoperative navigation, dose delivery, verification and follow-up of interstitial irradiation.Image fusion, understood as the visualization of any morphological volume (i.e. US, CT, MRI together with an additional second morpholo gical volume (i.e. CT, MRI or functional dataset (functional MRI, SPECT, PET, is a well known method for treatment planning, verification and follow-up of interstitial irradiation. The term image fusion is used when multiple patient image datasets are registered and overlaid or merged to provide additional information. Fused images may be created from multiple images from the same imaging modality taken at different moments (multi-temporalapproach, or by combining information from multiple modalities. Quality means that the fused images should provide additional information to the brachythe rapy process (diagnosis and staging, treatment planning, intraoperative imaging, treatment delivery and follow-up that cannot be obtained in other ways. In this review I will focus on the role of

  17. Maximum intensity projection MR angiography using shifted image data

    International Nuclear Information System (INIS)

    Machida, Yoshio; Ichinose, Nobuyasu; Hatanaka, Masahiko; Goro, Takehiko; Kitake, Shinichi; Hatta, Junicchi.

    1992-01-01

    The quality of MR angiograms has been significantly improved in past several years. Spatial resolution, however, is not sufficient for clinical use. On the other hand, MR image data can be filled at anywhere using Fourier shift theorem, and the quality of multi-planar reformed image has been reported to be improved remarkably using 'shifted data'. In this paper, we have clarified the efficiency of 'shifted data' for maximum intensity projection MR angiography. Our experimental studies and theoretical consideration showd that the quality of MR angiograms has been significantly improved using 'shifted data' as follows; 1) remarkable reduction of mosaic artifact, 2) improvement of spatial continuity for the blood vessels, and 3) reduction of variance for the signal intensity along the blood vessels. In other words, the angiograms looks much 'finer' than conventional ones, although the spatial resolution is not improved theoretically. Furthermore, we found the quality of MR angiograms dose not improve significantly with the 'shifted data' more than twice as dense as ordinal ones. (author)

  18. Pulmonary function-morphologic relationships assessed by SPECT-CT fusion images

    International Nuclear Information System (INIS)

    Suga, Kazuyoshi

    2012-01-01

    Pulmonary single photon emission computed tomography-computed tomography (SPECT-CT) fusion images provide objective and comprehensive assessment of pulmonary function and morphology relationships at cross-sectional lungs. This article reviewed the noteworthy findings of lung pathophysiology in wide-spectral lung disorders, which have been revealed on SPECT-CT fusion images in 8 years of experience. The fusion images confirmed the fundamental pathophysiologic appearance of lung low CT attenuation caused by airway obstruction-induced hypoxic vasoconstriction and that caused by direct pulmonary arterial obstruction as in acute pulmonary thromboembolism (PTE). The fusion images showed better correlation of lung perfusion distribution with lung CT attenuation changes at lung mosaic CT attenuation (MCA) compared with regional ventilation in the wide-spectral lung disorders, indicating that lung heterogeneous perfusion distribution may be a dominant mechanism of MCA on CT. SPECT-CT angiography fusion images revealed occasional dissociation between lung perfusion defects and intravascular clots in acute PTE, indicating the importance of assessment of actual effect of intravascular colts on peripheral lung perfusion. Perfusion SPECT-CT fusion images revealed the characteristic and preferential location of pulmonary infarction in acute PTE. The fusion images showed occasional unexpected perfusion defects in normal lung areas on CT in chronic obstructive pulmonary diseases and interstitial lung diseases, indicating the ability of perfusion SPECT superior to CT for detection of mild lesions in these disorders. The fusion images showed frequent ''steal phenomenon''-induced perfusion defects extending to the surrounding normal lung of arteriovenous fistulas and those at normal lungs on CT in hepatopulmonary syndrome. Comprehensive assessment of lung function-CT morphology on fusion images will lead to more profound understanding of lung pathophysiology in wide-spectral lung

  19. Multilevel segmentation of intracranial aneurysms in CT angiography images

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yan [Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California 94122 and University of Lyon, CREATIS, CNRS UMR 5220, INSERM U1206, UCB Lyon1, INSA Lyon, Lyon 69100 (France); Zhang, Yue, E-mail: y.zhang525@gmail.com [Veterans Affairs Medical Center, San Francisco, California 94121 and University of Lyon, CREATIS, CNRS UMR 5220, INSERM U1206, UCB Lyon1, INSA Lyon, Lyon 69100 (France); Navarro, Laurent [Ecole Nationale Superieure des Mines de Saint-Etienne, Saint-Etienne 42015 (France); Eker, Omer Faruk [CHU Montpellier, Neuroradiologie, Montpellier 34000 (France); Corredor Jerez, Ricardo A. [Ecole Polytechnique Federale de Lausanne, Lausanne 1015 (Switzerland); Chen, Yu; Zhu, Yuemin; Courbebaisse, Guy [University of Lyon, CREATIS, CNRS UMR 5220, INSERM U1206, UCB Lyon1, INSA Lyon, Lyon 69100 (France)

    2016-04-15

    Purpose: Segmentation of aneurysms plays an important role in interventional planning. Yet, the segmentation of both the lumen and the thrombus of an intracranial aneurysm in computed tomography angiography (CTA) remains a challenge. This paper proposes a multilevel segmentation methodology for efficiently segmenting intracranial aneurysms in CTA images. Methods: The proposed methodology first uses the lattice Boltzmann method (LBM) to extract the lumen part directly from the original image. Then, the LBM is applied again on an intermediate image whose lumen part is filled by the mean gray-level value outside the lumen, to yield an image region containing part of the aneurysm boundary. After that, an expanding disk is introduced to estimate the complete contour of the aneurysm. Finally, the contour detected is used as the initial contour of the level set with ellipse to refine the aneurysm. Results: The results obtained on 11 patients from different hospitals showed that the proposed segmentation was comparable with manual segmentation, and that quantitatively, the average segmentation matching factor (SMF) reached 86.99%, demonstrating good segmentation accuracy. Chan–Vese method, Sen’s model, and Luca’s model were used to compare the proposed method and their average SMF values were 39.98%, 40.76%, and 77.11%, respectively. Conclusions: The authors have presented a multilevel segmentation method based on the LBM and level set with ellipse for accurate segmentation of intracranial aneurysms. Compared to three existing methods, for all eleven patients, the proposed method can successfully segment the lumen with the highest SMF values for nine patients and second highest SMF values for the two. It also segments the entire aneurysm with the highest SMF values for ten patients and second highest SMF value for the one. This makes it potential for clinical assessment of the volume and aspect ratio of the intracranial aneurysms.

  20. Procedures for imaging of hemodialysis fistulas with particular reference to digital subtraction angiography (DSA)

    International Nuclear Information System (INIS)

    Neufang, K.F.R.; Erasmi-Koerber, H.; Wimmer, G.; Koeln Univ.

    1983-01-01

    All angiographic procedures established for imaging of hemodialysis fistulas, such as direct venous angiography, intravenous subtraction angiography and arteriography by direct puncture of the brachial artery of by Seldinger's transfemoral technique, can also be effected with digital image processing. Depending on the angiographic technique, the use of digital subtraction angiography has several advantages: lower doses and concentrations of the contrast agent, lower risk of complications (thrombosis of the fistula, vasospasm) and freedom from pain. In addition, there is a marked reduction of examination time and film cost. (orig.)

  1. Catheter Angiography

    Medline Plus

    Full Text Available ... medical test that helps physicians diagnose and treat medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection ...

  2. Three dimensional image alignment, registration and fusion

    International Nuclear Information System (INIS)

    Treves, S.T.; Mitchell, K.D.; Habboush, I.H.

    1998-01-01

    Combined assessment of three dimensional anatomical and functional images (SPECT, PET, MRI, CT) is useful to determine the nature and extent of lesions in many parts of the body. Physicians principally rely on their spatial sense of mentally re-orient and overlap images obtained with different imaging modalities. Objective methods that enable easy and intuitive image registration can help the physician arrive at more optimal diagnoses and better treatment decisions. This review describes a simple, intuitive and robust image registration approach developed in our laboratory. It differs from most other registration techniques in that it allows the user to incorporate all of the available information within the images in the registration process. This method takes full advantage of the ability of knowledgeable operators to achieve image registration and fusion using an intuitive interactive visual approach. It can register images accurately and quickly without the use of elaborate mathematical modeling or optimization techniques. The method provides the operator with tools to manipulate images in three dimensions, including visual feedback techniques to assess the accuracy of registration (grids, overlays, masks, and fusion of images in different colors). Its application is not limited to brain imaging and can be applied to images from any region in the body. The overall effect is a registration algorithm that is easy to implement and can achieve accuracy on the order of one pixel

  3. Alternate method for to realize image fusion

    International Nuclear Information System (INIS)

    Vargas, L.; Hernandez, F.; Fernandez, R.

    2005-01-01

    At the present time the image departments have the necessity of carrying out image fusion obtained of diverse apparatuses. Conventionally its fuse resonance or tomography images by X-rays with functional images as the gammagrams and PET images. The fusion technology is for sale with the modern image equipment and not all the cabinets of nuclear medicine have access to it. By this reason we analyze, study and we find a solution so that all the cabinets of nuclear medicine can benefit of the image fusion. The first indispensable requirement is to have a personal computer with capacity to put up image digitizer cards. It is also possible, if one has a gamma camera that can export images in JPG, GIF, TIFF or BMP formats, to do without of the digitizer card and to record the images in a disk to be able to use them in the personal computer. It is required of one of the following commercially available graph design programs: Corel Draw, Photo Shop, FreeHand, Illustrator or Macromedia Flash that are those that we evaluate and that its allow to make the images fusion. Anyone of them works well and a short training is required to be able to manage them. It is necessary a photographic digital camera with a resolution of at least 3.0 mega pixel. The procedure consists on taking photographic images of the radiological studies that the patient already has, selecting those demonstrative images of the pathology in study and that its can also be concordant with the images that we have created in the gammagraphic studies, whether for planar or tomographic. We transfer the images to the personal computer and we read them with the graph design program. To continuation also reads the gammagraphic images. We use those digital tools to make transparent the images, to clip them, to adjust the sizes and to create the fused images. The process is manual and it is requires of ability and experience to choose the images, the cuts, those sizes and the transparency grade. (Author)

  4. Spectrally Consistent Satellite Image Fusion with Improved Image Priors

    DEFF Research Database (Denmark)

    Nielsen, Allan Aasbjerg; Aanæs, Henrik; Jensen, Thomas B.S.

    2006-01-01

    Here an improvement to our previous framework for satellite image fusion is presented. A framework purely based on the sensor physics and on prior assumptions on the fused image. The contributions of this paper are two fold. Firstly, a method for ensuring 100% spectrally consistency is proposed......, even when more sophisticated image priors are applied. Secondly, a better image prior is introduced, via data-dependent image smoothing....

  5. Catheter Angiography

    Medline Plus

    Full Text Available ... you! Do you have a personal story about radiology? Share your patient story here Images × Image Gallery ... Contrast Materials CT Angiography (CTA) X-ray, Interventional Radiology and Nuclear Medicine Radiation Safety Images related to ...

  6. Contrast-enhanced MR angiography vs intra-arterial digital subtraction angiography for carotid imaging: activity-based cost analysis

    International Nuclear Information System (INIS)

    U-King-Im, Jean Marie; Cross, Justin J.; Higgins, Nicholas J.; Graves, Martin J.; Antoun, Nagui M.; Gillard, Jonathan H.; Hollingworth, William; Trivedi, Rikin A.; Kirkpatrick, Peter J.

    2004-01-01

    The aim of this study was to compare the costs of performing contrast-enhanced MR angiography (CE MRA) with intra-arterial digital subtraction angiography (DSA) for the evaluation of carotid atherosclerotic disease. Activity-based cost analysis was used to identify the costs of performing each procedure. The variable direct costs of performing CE MRA and DSA were determined in 20 patients by using detailed time and motion studies. All personnel directly involved in the cases were tracked to the nearest minute and all consumable items used were recorded. Moreover, procedure times were prospectively recorded for an additional 80 patients who underwent both DSA and CE MRA. The variable direct costs of bed usage in the angiography day-case unit, all direct fixed costs as well as indirect costs were assessed from hospital and departmental accounting records. Total costs for each procedure were calculated and compared using Wilcoxon signed-rank sum test. Mean aggregate costs were and euro;721 for DSA and and euro;306 for CE MRA, resulting in potential savings of and euro;415 per patient (p<0.0001). On average, a DSA procedure thus cost approximately 2.4 (95% confidence intervals: 2.2-2.6) times more than CE MRA to our medical institution. Sensitivity analyses confirmed the robustness of our conclusions across wide ranges of plausible values for various parameters. Assuming equal diagnostic performance, institutions may have substantial cost savings if CE MRA is used instead of DSA for carotid imaging. (orig.)

  7. Contrast-enhanced MR angiography vs intra-arterial digital subtraction angiography for carotid imaging: activity-based cost analysis

    Energy Technology Data Exchange (ETDEWEB)

    U-King-Im, Jean Marie; Cross, Justin J.; Higgins, Nicholas J.; Graves, Martin J.; Antoun, Nagui M.; Gillard, Jonathan H. [University Department of Radiology, Addenbrooke' s Hospital, CB2 2QQ, Cambridge (United Kingdom); Hollingworth, William [Department of Radiology, University of Washington, WA 98103, Seattle (United States); Trivedi, Rikin A. [University Department of Radiology, Addenbrooke' s Hospital, CB2 2QQ, Cambridge (United Kingdom); Academic Department of Neurosurgery, Addenbrooke' s Hospital, CB2 2QQ, Cambridge (United Kingdom); Kirkpatrick, Peter J. [Academic Department of Neurosurgery, Addenbrooke' s Hospital, CB2 2QQ, Cambridge (United Kingdom)

    2004-04-01

    The aim of this study was to compare the costs of performing contrast-enhanced MR angiography (CE MRA) with intra-arterial digital subtraction angiography (DSA) for the evaluation of carotid atherosclerotic disease. Activity-based cost analysis was used to identify the costs of performing each procedure. The variable direct costs of performing CE MRA and DSA were determined in 20 patients by using detailed time and motion studies. All personnel directly involved in the cases were tracked to the nearest minute and all consumable items used were recorded. Moreover, procedure times were prospectively recorded for an additional 80 patients who underwent both DSA and CE MRA. The variable direct costs of bed usage in the angiography day-case unit, all direct fixed costs as well as indirect costs were assessed from hospital and departmental accounting records. Total costs for each procedure were calculated and compared using Wilcoxon signed-rank sum test. Mean aggregate costs were and euro;721 for DSA and and euro;306 for CE MRA, resulting in potential savings of and euro;415 per patient (p<0.0001). On average, a DSA procedure thus cost approximately 2.4 (95% confidence intervals: 2.2-2.6) times more than CE MRA to our medical institution. Sensitivity analyses confirmed the robustness of our conclusions across wide ranges of plausible values for various parameters. Assuming equal diagnostic performance, institutions may have substantial cost savings if CE MRA is used instead of DSA for carotid imaging. (orig.)

  8. Live Imaging of Mouse Secondary Palate Fusion

    Czech Academy of Sciences Publication Activity Database

    Kim, S.; Procházka, Jan; Bush, J.O.

    jaro, č. 125 (2017), č. článku e56041. ISSN 1940-087X Institutional support: RVO:68378050 Keywords : Developmental Biology * Issue 125 * live imaging * secondary palate * tissue fusion * cleft * craniofacial Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Developmental biology Impact factor: 1.232, year: 2016

  9. Model-based satellite image fusion

    DEFF Research Database (Denmark)

    Aanæs, Henrik; Sveinsson, J. R.; Nielsen, Allan Aasbjerg

    2008-01-01

    A method is proposed for pixel-level satellite image fusion derived directly from a model of the imaging sensor. By design, the proposed method is spectrally consistent. It is argued that the proposed method needs regularization, as is the case for any method for this problem. A framework for pixel...... neighborhood regularization is presented. This framework enables the formulation of the regularization in a way that corresponds well with our prior assumptions of the image data. The proposed method is validated and compared with other approaches on several data sets. Lastly, the intensity......-hue-saturation method is revisited in order to gain additional insight of what implications the spectral consistency has for an image fusion method....

  10. Biometric image enhancement using decision rule based image fusion techniques

    Science.gov (United States)

    Sagayee, G. Mary Amirtha; Arumugam, S.

    2010-02-01

    Introducing biometrics into information systems may result in considerable benefits. Most of the researchers confirmed that the finger print is widely used than the iris or face and more over it is the primary choice for most privacy concerned applications. For finger prints applications, choosing proper sensor is at risk. The proposed work deals about, how the image quality can be improved by introducing image fusion technique at sensor levels. The results of the images after introducing the decision rule based image fusion technique are evaluated and analyzed with its entropy levels and root mean square error.

  11. Magnetic resonance angiography of the pediatric abdomen and pelvis: techniques and imaging findings.

    Science.gov (United States)

    Sada, David M; Vellody, Ranjith; Liu, Peter S

    2013-11-01

    Although traditional catheter-based angiography has been the gold standard for pediatric abdominal and pelvic vascular imaging for the past several decades, advances in magnetic resonance angiography (MRA) have made it a viable alternative. MRA offers several advantages in that it is noninvasive, can be performed without ionizing radiation, and does not necessarily rely on contrast administration. The ability of modern MRA techniques to define variant vascular anatomy and detect vascular disease may obviate traditional angiography in some patients. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Patient satisfaction with coronary CT angiography, myocardial CT perfusion, myocardial perfusion MRI, SPECT myocardial perfusion imaging and conventional coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Feger, S.; Rief, M.; Zimmermann, E.; Richter, F.; Roehle, R. [Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Humboldt-Universitaet zu Berlin, Berlin (Germany); Dewey, M. [Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Humboldt-Universitaet zu Berlin, Berlin (Germany); Institut fuer Radiologie, Berlin (Germany); Schoenenberger, E. [Medizinische Hochschule Hannover, Department of Medicine, Hannover (Germany)

    2015-07-15

    To evaluate patient acceptance of noninvasive imaging tests for detection of coronary artery disease (CAD), including single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI), stress perfusion magnetic resonance imaging (MRI), coronary CT angiography (CTA) in combination with CT myocardial stress perfusion (CTP), and conventional coronary angiography (CCA). Intraindividual comparison of perception of 48 patients from the CORE320 multicentre multinational study who underwent rest and stress SPECT-MPI with a technetium-based tracer, combined CTA and CTP (both with contrast agent, CTP with adenosine), MRI, and CCA. The analysis was performed by using a validated questionnaire. Patients had significantly more concern prior to CCA than before CTA/CTP (p < 0.001). CTA/CTP was also rated as more comfortable than SPECT-MPI (p = 0.001). Overall satisfaction with CT was superior to that of MRI (p = 0.007). More patients preferred CT (46 %; p < 0.001) as a future diagnostic test. Regarding combined CTA/CTP, CTP was characterised by higher pain levels and an increased frequency of angina pectoris during the examination (p < 0.001). Subgroup analysis showed a higher degree of pain during SPECT-MPI with adenosine stress compared to physical exercise (p = 0.016). All noninvasive cardiac imaging tests are well accepted by patients, with CT being the preferred examination. (orig.)

  13. Image fusion for dynamic contrast enhanced magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Leach Martin O

    2004-10-01

    Full Text Available Abstract Background Multivariate imaging techniques such as dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI have been shown to provide valuable information for medical diagnosis. Even though these techniques provide new information, integrating and evaluating the much wider range of information is a challenging task for the human observer. This task may be assisted with the use of image fusion algorithms. Methods In this paper, image fusion based on Kernel Principal Component Analysis (KPCA is proposed for the first time. It is demonstrated that a priori knowledge about the data domain can be easily incorporated into the parametrisation of the KPCA, leading to task-oriented visualisations of the multivariate data. The results of the fusion process are compared with those of the well-known and established standard linear Principal Component Analysis (PCA by means of temporal sequences of 3D MRI volumes from six patients who took part in a breast cancer screening study. Results The PCA and KPCA algorithms are able to integrate information from a sequence of MRI volumes into informative gray value or colour images. By incorporating a priori knowledge, the fusion process can be automated and optimised in order to visualise suspicious lesions with high contrast to normal tissue. Conclusion Our machine learning based image fusion approach maps the full signal space of a temporal DCE-MRI sequence to a single meaningful visualisation with good tissue/lesion contrast and thus supports the radiologist during manual image evaluation.

  14. The impact of exercise myocardial perfusion SPECT imaging on the selection of patients for coronary angiography

    International Nuclear Information System (INIS)

    Song Liping; He Zuoxiang; Liu Xiujie; Shi Rongfang; Liu Yunzhong; Tian Yueqin; Zhang Xiaoli; Qin Xuewen; Chen Jilin; Gao Runlin

    2001-01-01

    Objective: Exercise 99 Tc m -MIBI myocardial perfusion SPECT is accurate for the diagnosis of coronary artery disease (CAD). This study assessed the impact of exercise myocardial perfusion imaging on the selection of patients for coronary angiography. Methods: 2188 consecutive patients who underwent exercise myocardial perfusion SPECT in authors' department in 1999 were retrospectively analyzed. Among them, 1807 were men, 381 women (average age: 53.5 +- 7.2 years). Overall, exercise myocardial SPECT was normal in 1731 patients, abnormal in 359 cases, and equivocal in 98 patients. There were 141 patients who underwent CAG within 60 days after myocardial SPECT. Results: Overall, 12% of the patients with abnormal SPECT imaging underwent coronary angiography, but only 5% of the patients with a normal SPECT imaging did (P < 0.001). Among these 141 patients who underwent coronary angiography, significant coronary stenosis was present in 91% of the patients who had had an abnormal SPECT imaging, but only 8% of those who had had a normal SPECT imaging (P < 0.001). In those patients who underwent coronary angiography, revascularization rate was 25% for the patients with abnormal SPECT imaging, but only 1% for the patients with a normal SPECT imaging. Conclusion: The results of exercise myocardial perfusion SPECT have a significant impact on the selection of patients for coronary angiography and revascularization

  15. A hybrid image fusion system for endovascular interventions of peripheral artery disease.

    Science.gov (United States)

    Lalys, Florent; Favre, Ketty; Villena, Alexandre; Durrmann, Vincent; Colleaux, Mathieu; Lucas, Antoine; Kaladji, Adrien

    2018-03-16

    Interventional endovascular treatment has become the first line of management in the treatment of peripheral artery disease (PAD). However, contrast and radiation exposure continue to limit the feasibility of these procedures. This paper presents a novel hybrid image fusion system for endovascular intervention of PAD. We present two different roadmapping methods from intra- and pre-interventional imaging that can be used either simultaneously or independently, constituting the navigation system. The navigation system is decomposed into several steps that can be entirely integrated within the procedure workflow without modifying it to benefit from the roadmapping. First, a 2D panorama of the entire peripheral artery system is automatically created based on a sequence of stepping fluoroscopic images acquired during the intra-interventional diagnosis phase. During the interventional phase, the live image can be synchronized on the panorama to form the basis of the image fusion system. Two types of augmented information are then integrated. First, an angiography panorama is proposed to avoid contrast media re-injection. Information exploiting the pre-interventional computed tomography angiography (CTA) is also brought to the surgeon by means of semiautomatic 3D/2D registration on the 2D panorama. Each step of the workflow was independently validated. Experiments for both the 2D panorama creation and the synchronization processes showed very accurate results (errors of 1.24 and [Formula: see text] mm, respectively), similarly to the registration on the 3D CTA (errors of [Formula: see text] mm), with minimal user interaction and very low computation time. First results of an on-going clinical study highlighted its major clinical added value on intraoperative parameters. No image fusion system has been proposed yet for endovascular procedures of PAD in lower extremities. More globally, such a navigation system, combining image fusion from different 2D and 3D image

  16. Catheter Angiography

    Medline Plus

    Full Text Available ... imaging (MRI) In catheter angiography, a thin plastic tube, called a catheter , is inserted into an artery ... examined, a contrast material is injected through the tube and images are captured using a small dose ...

  17. Color image guided depth image super resolution using fusion filter

    Science.gov (United States)

    He, Jin; Liang, Bin; He, Ying; Yang, Jun

    2018-04-01

    Depth cameras are currently playing an important role in many areas. However, most of them can only obtain lowresolution (LR) depth images. Color cameras can easily provide high-resolution (HR) color images. Using color image as a guide image is an efficient way to get a HR depth image. In this paper, we propose a depth image super resolution (SR) algorithm, which uses a HR color image as a guide image and a LR depth image as input. We use the fusion filter of guided filter and edge based joint bilateral filter to get HR depth image. Our experimental results on Middlebury 2005 datasets show that our method can provide better quality in HR depth images both numerically and visually.

  18. Development of technology for medical image fusion

    International Nuclear Information System (INIS)

    Yamaguchi, Takashi; Amano, Daizou

    2012-01-01

    With entry into a field of medical diagnosis in mind, we have developed positron emission tomography (PET) ''MIP-100'' system, of which spatial resolution is far higher than the conventional one, using semiconductor detectors for preclinical imaging for small animals. In response to the recently increasing market demand to fuse functional images by PET and anatomical ones by CT or MRI, we have been developing software to implement image fusion function that enhances marketability of the PET Camera. This paper describes the method of fusing with high accuracy the PET images and anatomical ones by CT system. It also explains that a computer simulation proved the image overlay accuracy to be ±0.3 mm as a result of the development, and that effectiveness of the developed software is confirmed in case of experiment to obtain measured data. Achieving such high accuracy as ±0.3 mm by the software allows us to present fusion images with high resolution (<0.6 mm) without degrading the spatial resolution (<0.5 mm) of the PET system using semiconductor detectors. (author)

  19. Videodensitometric quantitative angiography after coronary balloon angioplasty, compared to edge-detection quantitative angiography and intracoronary ultrasound imaging

    NARCIS (Netherlands)

    Peters, R. J.; Kok, W. E.; Pasterkamp, G.; von Birgelen, C.; Prins, M. [=Martin H.; Serruys, P. W.

    2000-01-01

    AIMS: To assess the value of videodensitometric quantification of the coronary lumen after angioplasty by comparison to two other techniques of coronary artery lumen quantification. METHODS AND RESULTS: Videodensitometric quantitative angiography, edge detection quantitative angiography and 30 MHz

  20. Assessment of fusion operators for medical imaging: application to MR images fusion

    International Nuclear Information System (INIS)

    Barra, V.; Boire, J.Y.

    2000-01-01

    We propose in the article to assess the results provided by several fusion operators in the case of T 1 - and T 2 -weighted magnetic resonance images fusion of the brain. This assessment deals with an expert visual inspection of the results and with a numerical analysis of some comparison measures found in the literature. The aim of this assessment is to find the 'best' operator according to the clinical study. This method is here applied to the quantification of brain tissue volumes on a brain phantom, and allows to select a fusion operator in any clinical study where several information is available. (authors)

  1. Added Value of 3D Cardiac SPECT/CTA Fusion Imaging in Patients with Reversible Perfusion Defect on Myocardial Perfusion SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Eun Jung; Cho, Ihn Ho [Yeungnam University Hospital, Daegu (Korea, Republic of); Kang, Won Jun [Yonsei University Hospital, Seoul (Korea, Republic of); Kim, Seong Min [Chungnam National University Medical School and Hospital, Daejeon (Korea, Republic of); Won, Kyoung Sook [Keomyung University Dongsan Hospital, Daegu (Korea, Republic of); Lim, Seok Tae [Chonbuk National University Medical School and Hospital, Jeonju (Korea, Republic of); Hwang, Kyung Hoon [Gachon University Gil Hospital, Incheon (Korea, Republic of); Lee, Byeong Il; Bom, Hee Seung [Chonnam National University Medical School and Hospital, Gwangju (Korea, Republic of)

    2009-12-15

    Integration of the functional information of myocardial perfusion SPECT (MPS) and the morphoanatomical information of coronary CT angiography (CTA) may provide useful additional diagnostic information of the spatial relationship between perfusion defects and coronary stenosis. We studied to know the added value of three dimensional cardiac SPECT/CTA fusion imaging (fusion image) by comparing between fusion image and MPS. Forty-eight patients (M:F=26:22, Age: 63.3{+-}10.4 years) with a reversible perfusion defect on MPS (adenosine stress/rest SPECT with Tc-99m sestamibi or tetrofosmin) and CTA were included. Fusion images were molded and compared with the findings from the MPS. Invasive coronary angiography served as a reference standard for fusion image and MPS. Total 144 coronary arteries in 48 patients were analyzed; Fusion image yielded the sensitivity, specificity, negative and positive predictive value for the detection of hemodynamically significant stenosis per coronary artery 82.5%, 79.3%, 76.7% and 84.6%, respectively. Respective values for the MPS were 68.8%, 70.7%, 62.1% and 76.4%. And fusion image also could detect more multi-vessel disease. Fused three dimensional volume-rendered SPECT/CTA imaging provides intuitive convincing information about hemodynamic relevant lesion and could improved diagnostic accuracy.

  2. Magnetic Resonance Imaging and Angiography for the Prerupture Diagnosis of Rudimentary Uterine Horn Pregnancy

    Energy Technology Data Exchange (ETDEWEB)

    Ozeren, S.; Caliskan, E.; Corakci, A.; Ozkan, S.; Demirci, A. [Kocaeli Univ., Faculty of Medicine, Kocaeli (Turkey). Dept. of Obstetrics and Gynecology

    2004-12-01

    Magnetic resonance (MR) imaging and MR angiography were used for the differential diagnosis and preoperative planning of a 17 weeks of age rudimentary horn pregnancy. A 26-year-old primigravida was referred to our hospital with a preliminary diagnosis of abdominal pregnancy. After an inconclusive ultrasound evaluation we were able to identify a rudimentary horn pregnancy, extent of the placental invasion, and the vascular supply via MR imaging and time of flight sequence MR angiography. The obtained data were also used for preoperative planning, which resulted in an uncomplicated, prerupture laparotomy for pregnancy termination and a healthy female.

  3. Early Detection of Diabetic Retinopathy in Fluorescent Angiography Retinal Images Using Image Processing Methods

    Directory of Open Access Journals (Sweden)

    Meysam Tavakoli

    2010-12-01

    Full Text Available Introduction: Diabetic retinopathy (DR is the single largest cause of sight loss and blindness in the working age population of Western countries; it is the most common cause of blindness in adults between 20 and 60 years of age. Early diagnosis of DR is critical for preventing vision loss so early detection of microaneurysms (MAs as the first signs of DR is important. This paper addresses the automatic detection of MAs in fluorescein angiography fundus images, which plays a key role in computer assisted diagnosis of DR, a serious and frequent eye disease. Material and Methods: The algorithm can be divided into three main steps. The first step or pre-processing was for background normalization and contrast enhancement of the image. The second step aimed at detecting landmarks, i.e., all patterns possibly corresponding to vessels and the optic nerve head, which was achieved using a local radon transform. Then, MAs were extracted, which were used in the final step to automatically classify candidates into real MA and other objects. A database of 120 fluorescein angiography fundus images was used to train and test the algorithm. The algorithm was compared to manually obtained gradings of those images. Results: Sensitivity of diagnosis for DR was 94%, with specificity of 75%, and sensitivity of precise microaneurysm localization was 92%, at an average number of 8 false positives per image. Discussion and Conclusion: Sensitivity and specificity of this algorithm make it one of the best methods in this field. Using local radon transform in this algorithm eliminates the noise sensitivity for microaneurysm detection in retinal image analysis.

  4. Catheter Angiography

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Catheter Angiography Catheter angiography ...

  5. Catheter Angiography

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician ... Catheter Angiography? Angiography is a minimally invasive medical test that helps physicians diagnose and treat medical conditions. ...

  6. Cardiovascular CT angiography in neonates and children : Image quality and potential for radiation dose reduction with iterative image reconstruction techniques

    NARCIS (Netherlands)

    Tricarico, Francesco; Hlavacek, Anthony M.; Schoepf, U. Joseph; Ebersberger, Ullrich; Nance, John W.; Vliegenthart, Rozemarijn; Cho, Young Jun; Spears, J. Reid; Secchi, Francesco; Savino, Giancarlo; Marano, Riccardo; Schoenberg, Stefan O.; Bonomo, Lorenzo; Apfaltrer, Paul

    To evaluate image quality (IQ) of low-radiation-dose paediatric cardiovascular CT angiography (CTA), comparing iterative reconstruction in image space (IRIS) and sinogram-affirmed iterative reconstruction (SAFIRE) with filtered back-projection (FBP) and estimate the potential for further dose

  7. Color Multifocus Image Fusion Using Empirical Mode Decomposition

    Directory of Open Access Journals (Sweden)

    S. Savić

    2013-11-01

    Full Text Available In this paper, a recently proposed grayscale multifocus image fusion method based on the first level of Empirical Mode Decomposition (EMD has been extended to color images. In addition, this paper deals with low contrast multifocus image fusion. The major advantages of the proposed methods are simplicity, absence of artifacts and control of contrast, while this isn’t the case with other pyramidal multifocus fusion methods. The efficiency of the proposed method is tested subjectively and with a vector gradient based objective measure, that is proposed in this paper for multifocus color image fusion. Subjective analysis performed on a multifocus image dataset has shown its superiority to the existing EMD and DWT based methods. The objective measures of grayscale and color image fusion show significantly better scores for this method than for the classic complex EMD fusion method.

  8. Contrast-enhanced magnetic resonance angiography in carotid artery disease: does automated image registration improve image quality?

    International Nuclear Information System (INIS)

    Menke, Jan; Larsen, Joerg

    2009-01-01

    Contrast-enhanced magnetic resonance angiography (MRA) is a noninvasive imaging alternative to digital subtraction angiography (DSA) for patients with carotid artery disease. In DSA, image quality can be improved by shifting the mask image if the patient has moved during angiography. This study investigated whether such image registration may also help to improve the image quality of carotid MRA. Data from 370 carotid MRA examinations of patients likely to have carotid artery disease were prospectively collected. The standard nonregistered MRAs were compared to automatically linear, affine and warp registered MRA by using three image quality parameters: the vessel detection probability (VDP) in maximum intensity projection (MIP) images, contrast-to-noise ratio (CNR) in MIP images, and contrast-to-noise ratio in three-dimensional image volumes. A body shift of less than 1 mm occurred in 96.2% of cases. Analysis of variance revealed no significant influence of image registration and body shift on image quality (p > 0.05). In conclusion, standard contrast-enhanced carotid MRA usually requires no image registration to improve image quality and is generally robust against any naturally occurring body shift. (orig.)

  9. Computed tomography angiography in acute stroke (revisiting the 4Ps of imaging).

    Science.gov (United States)

    Varadharajan, Shriram; Saini, Jitender; Acharya, Ullas V; Gupta, Arun Kumar

    2016-02-01

    Imaging in acute stroke has traditionally focussed on the 4Ps-parenchyma, pipes, perfusion, and penumbra-and has increasingly relied upon advanced techniques including magnetic resonance imaging to evaluate such patients. However, as per European Magnetic Resonance Forum estimates, the availability of magnetic resonance imaging scanners for the general population in India (0.5 per million inhabitants) is quite low as compared to Europe (11 per million) and United States (35 per million), with most of them only present in urban cities. On the other hand, computed tomography (CT) is more widely available and has reduced scanning duration. Computed tomography angiography of cervical and intracranial vessels is relatively simpler to perform with extended coverage and can provide all pertinent information required in such patients. This imaging review will discuss relevant imaging findings on CT angiography in patients with acute ischemic stroke through illustrated cases. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Improved Imaging in Cardiac Patients: echocardiography and CT-coronary angiography

    NARCIS (Netherlands)

    T.W. Galema (Tjebbe)

    2010-01-01

    textabstractDiff erent non-invasive imaging modalities are used for to assess cardiac anatomy and function. Echocardiography and MRI allow assessment of cardiac structures and function of the cardiac chambers and valves as well as perfusion of the left ventricular wall while CT-angiography in

  11. Normal diffusion-weighted imaging in cerebral air embolism complicating angiography

    Energy Technology Data Exchange (ETDEWEB)

    Sayama, T.; Inamura, T.; Fukui, M. [Dept. of Neurosurgery, Kyushu University Hospital, Fukuoka (Japan); Mitani, M.; Yagi, H. [Dept. of Neurosurgery, Yagi Hospital, Fukuoka (Japan)

    2000-03-01

    We report a case of cerebral air embolism resulting from accidental air infection during cerebral angiography. A 60-year-old man was accidentally injected with air via the left subclavian artery. Angiography demonstrated air within the basilar artery. The patient showed signs of posterior circulation ischaemia (confusion, blindness, gaze palsy and hemiparesis). However, MRI, including diffusion-weighted imaging, showed no abnormality 4 h later. The patient was treated with hyperbaric oxygen within 5 h of the embolism. All symptoms and signs resolved completely within a week. (orig.)

  12. Anatomic and functional imaging of congenital heart disease with digital subtraction angiography

    International Nuclear Information System (INIS)

    Buonocore, E.; Pavlicek, W.; Modic, M.T.; Meaney, T.F.; O'Donovan, P.B.; Grossman, L.B.; Moodie, D.S.; Yiannikas, J.

    1983-01-01

    Digital subtraction angiography (DSA) of the heart was performed in 54 patients for the evaluation of congenital heart diagnostic images and accurate physiologic shunt data that compared favorably with catheter angiography and nuclear medicine studies. Retrospective analysis of this series of patients indicated that DSA studies contributed sufficient informantion to shorten significantly or modify cardiac catheterization in 85% (79/93) of the defects that were identified. Interatrial septal defects were particularly well diagnosed, with identification occurring in 10 of 10 cases, wheseas intraventricular septal defects were identified in only 6 of 9 patients. Evaluation of postsurgical patients was accurate in 19 of 20 cases

  13. Anato-metabolic fusion of PET, CT and MRI images

    International Nuclear Information System (INIS)

    Przetak, C.; Baum, R.P.; Niesen, A.; Slomka, P.; Proeschild, A.; Leonhardi, J.

    2000-01-01

    The fusion of cross-sectional images - especially in oncology - appears to be a very helpful tool to improve the diagnostic and therapeutic accuracy. Though many advantages exist, image fusion is applied routinely only in a few hospitals. To introduce image fusion as a common procedure, technical and logistical conditions have to be fulfilled which are related to long term archiving of digital data, data transfer and improvement of the available software in terms of usefulness and documentation. The accuracy of coregistration and the quality of image fusion has to be validated by further controlled studies. (orig.) [de

  14. Ischemic lesions related to cerebral angiography: Evaluation by diffusion weighted MR imaging

    International Nuclear Information System (INIS)

    Kato, Koki; Tomura, Noriaki; Takahashi, Satoshi; Sakuma, Ikuo; Watarai, Jiro

    2003-01-01

    We examined the incidence of ischemic lesions occurring after cerebral angiography by means of diffusion weighted MR imaging (DWI). Fifty patients were included in this study. Balloon occlusion tests of the internal carotid artery were performed in 9 of the 50 patients. DWI was performed on the same day as the cerebral angiography or on the following day. No new neurological deficits were found after cerebral angiography. However, 13 of the 50 cases revealed new ischemic lesions after cerebral angiography. The incidence of ischemic lesions was significantly different between patients who underwent balloon occlusion tests and patients who did not. The incidence of ischemic lesions was not influenced by the duration of the procedure, use of additional catheters, total amount of contrast material or the type of contrast material. The incidence of clinically silent ischemic lesions related to cerebral angiography is greater than the incidence of neurological complications. In patients who underwent occlusion tests of the internal carotid artery, the incidence of silent lesions was significantly higher than in patients who did not. (orig.)

  15. Catheter Angiography

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    Full Text Available ... medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection ... a tendency to bleed. top of page Additional Information and Resources Society of Interventional Radiology (SIR) - Patient ...

  16. Catheter Angiography

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    Full Text Available ... medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection ... at these links. About Us | Contact Us | FAQ | Privacy | Terms of Use | Links | Site Map Copyright © 2018 ...

  17. Catheter Angiography

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    Full Text Available ... medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection ... possible charges you will incur. Web page review process: This Web page is reviewed regularly by a ...

  18. Catheter Angiography

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    Full Text Available ... medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection ... congenital abnormalities in blood vessels, especially arteries in children (e.g., malformations in the heart or other ...

  19. Catheter Angiography

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    Full Text Available ... medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection ... far outweighs the risk. If you have a history of allergy to x-ray contrast material, your ...

  20. Catheter Angiography

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    Full Text Available ... Catheter angiography uses a catheter, x-ray imaging guidance and an injection of contrast material to examine ... removable dental appliances, eye glasses and any metal objects or clothing that might interfere with the x- ...

  1. Catheter Angiography

    Medline Plus

    Full Text Available ... medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection ... American College of Radiology (ACR) and the European Society of Urogenital Radiology note that the available data ...

  2. Catheter Angiography

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    Full Text Available ... medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection ... in key areas of the body, including the: brain neck heart chest abdomen (such as the kidneys ...

  3. Catheter Angiography

    Medline Plus

    Full Text Available ... medical conditions. Angiography uses one of three imaging technologies and, in most cases, a contrast material injection ... The video is produced by the x-ray machine and a detector that is suspended over a ...

  4. Catheter Angiography

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    Full Text Available Toggle navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us News Physician Resources Professions Site Index A-Z Catheter Angiography ...

  5. An FPGA-based heterogeneous image fusion system design method

    Science.gov (United States)

    Song, Le; Lin, Yu-chi; Chen, Yan-hua; Zhao, Mei-rong

    2011-08-01

    Taking the advantages of FPGA's low cost and compact structure, an FPGA-based heterogeneous image fusion platform is established in this study. Altera's Cyclone IV series FPGA is adopted as the core processor of the platform, and the visible light CCD camera and infrared thermal imager are used as the image-capturing device in order to obtain dualchannel heterogeneous video images. Tailor-made image fusion algorithms such as gray-scale weighted averaging, maximum selection and minimum selection methods are analyzed and compared. VHDL language and the synchronous design method are utilized to perform a reliable RTL-level description. Altera's Quartus II 9.0 software is applied to simulate and implement the algorithm modules. The contrast experiments of various fusion algorithms show that, preferably image quality of the heterogeneous image fusion can be obtained on top of the proposed system. The applied range of the different fusion algorithms is also discussed.

  6. Joint Multi-Focus Fusion and Bayer ImageRestoration

    Institute of Scientific and Technical Information of China (English)

    Ling Guo; Bin Yang; Chao Yang

    2015-01-01

    In this paper, a joint multifocus image fusion and Bayer pattern image restoration algorithm for raw images of single-sensor colorimaging devices is proposed. Different from traditional fusion schemes, the raw Bayer pattern images are fused before colorrestoration. Therefore, the Bayer image restoration operation is only performed one time. Thus, the proposed algorithm is moreefficient than traditional fusion schemes. In detail, a clarity measurement of Bayer pattern image is defined for raw Bayer patternimages, and the fusion operator is performed on superpixels which provide powerful grouping cues of local image feature. Theraw images are merged with refined weight map to get the fused Bayer pattern image, which is restored by the demosaicingalgorithm to get the full resolution color image. Experimental results demonstrate that the proposed algorithm can obtain betterfused results with more natural appearance and fewer artifacts than the traditional algorithms.

  7. Subtracted versus non-subtracted digital imaging in peripheral angiography

    International Nuclear Information System (INIS)

    Fink, U.; Heywang, S.; Mayr, B.; Berger, H.

    1989-01-01

    Digital subtraction angiography (DSA) plays an important role in the management of vascular diseases of the lower extremities. A disadvantage is the lack of an automatically moving table top. We used a 1,024x1,024 matrix with a large-screen intensifier system and an automated 'stepping' facility. In 161 examinations of the arteries of the lower extremity digital peripheral arteriography was performed with and without the subtraction technique. We compared the influence of different iodine concentrations in DA and DSA. Peripheral DA proved to be equal to peripheral DSA in the region of the pelvis, thigh and knee, with no adequate contrasting being obtained merely in the region of the lower leg arteries in about 45%. It is necessary to use contrast medium at a concentration of 300 mg I/ml. The installation of an automated 'stepping' facility reduces the amount of contrast' medium needed and the exposure time. (orig.)

  8. INTEGRATED FUSION METHOD FOR MULTIPLE TEMPORAL-SPATIAL-SPECTRAL IMAGES

    Directory of Open Access Journals (Sweden)

    H. Shen

    2012-08-01

    Full Text Available Data fusion techniques have been widely researched and applied in remote sensing field. In this paper, an integrated fusion method for remotely sensed images is presented. Differently from the existed methods, the proposed method has the performance to integrate the complementary information in multiple temporal-spatial-spectral images. In order to represent and process the images in one unified framework, two general image observation models are firstly presented, and then the maximum a posteriori (MAP framework is used to set up the fusion model. The gradient descent method is employed to solve the fused image. The efficacy of the proposed method is validated using simulated images.

  9. Image fusion via nonlocal sparse K-SVD dictionary learning.

    Science.gov (United States)

    Li, Ying; Li, Fangyi; Bai, Bendu; Shen, Qiang

    2016-03-01

    Image fusion aims to merge two or more images captured via various sensors of the same scene to construct a more informative image by integrating their details. Generally, such integration is achieved through the manipulation of the representations of the images concerned. Sparse representation plays an important role in the effective description of images, offering a great potential in a variety of image processing tasks, including image fusion. Supported by sparse representation, in this paper, an approach for image fusion by the use of a novel dictionary learning scheme is proposed. The nonlocal self-similarity property of the images is exploited, not only at the stage of learning the underlying description dictionary but during the process of image fusion. In particular, the property of nonlocal self-similarity is combined with the traditional sparse dictionary. This results in an improved learned dictionary, hereafter referred to as the nonlocal sparse K-SVD dictionary (where K-SVD stands for the K times singular value decomposition that is commonly used in the literature), and abbreviated to NL_SK_SVD. The performance of the NL_SK_SVD dictionary is applied for image fusion using simultaneous orthogonal matching pursuit. The proposed approach is evaluated with different types of images, and compared with a number of alternative image fusion techniques. The resultant superior fused images using the present approach demonstrates the efficacy of the NL_SK_SVD dictionary in sparse image representation.

  10. The influence factors in image quality of multi-slice spiral CT coronary angiography (MSCTA)

    International Nuclear Information System (INIS)

    Zeng Huiliang; Zhu Xinjin; Liang Jianhao; Zhong Yingze; Chen Xueguang; Ou Weiqian; Wen Haomao; Li Peiwen

    2007-01-01

    Objective: To evaluate the influence of heart rate on image quality of multi-slice spiral CT coronary angiography(MSCTA) and the optimization of image reconstruction windows. Methods: Retrospectively ECG-gated MSCT coronary angiography were performed in 67 cases. The cases were divided into four groups by heart rate, groupl with heart rate less than 60 beats per minute(bpm), group 2 with heart rate 61-70 bpm, group 3 with heart rate 71-80 bpm and group 4 with heart rate over 81 bpm. The impact of heart rate on image quality of MSCTA and the optimization of image reconstruction windows were evaluated. Results: 4 coronary (RCA,LM,LAD,LCX) segments were analyzed in each patients with regard to image quality. 86.7%(112/128) of the coronary segments were sufficient for analysis in patients with heart rate less than 60 bpm,62.5%(55/88) with 61-70 bpm,40%(8/20) with 71-80 bpm and 12.5%(2/16) with heart rate over 81 bpm, respectively. There were statistically significances between every coronary segments of group 1 and 2, group 3 and 4 (P<0.05). All coronary segments of group 1 were optimally visualized on the image reconstructed at 75% image reconstruction window of' cardiac cycle; 89.5% cases at 75% in group 2; for group 3.55% of coronary artery were best presented at 75% image reconstruction window, 45% of coronary artery at 45%; All coronary segments of group 4 were optimally visualized on the image reconstructed at 45% image reconstruction window. Conclusion: Image quality of MSCT coronary angiography is highly dependent on heart rate. Coronary artery is usually best shown at 75% image reconstruction window of cardiac cycle for those with heart rate less than 70 bpm. 30%-90% image reconstruction should be performed when heart rate is over 71 bpm. (authors)

  11. Aqueous Angiography: Real-Time and Physiologic Aqueous Humor Outflow Imaging.

    Directory of Open Access Journals (Sweden)

    Sindhu Saraswathy

    Full Text Available Trabecular meshwork (TM bypass surgeries attempt to enhance aqueous humor outflow (AHO to lower intraocular pressure (IOP. While TM bypass results are promising, inconsistent success is seen. One hypothesis for this variability rests upon segmental (non-360 degrees uniform AHO. We describe aqueous angiography as a real-time and physiologic AHO imaging technique in model eyes as a way to simulate live AHO imaging.Pig (n = 46 and human (n = 6 enucleated eyes were obtained, orientated based upon inferior oblique insertion, and pre-perfused with balanced salt solution via a Lewicky AC maintainer through a 1mm side-port. Fluorescein (2.5% was introduced intracamerally at 10 or 30 mm Hg. With an angiographer, infrared and fluorescent (486 nm images were acquired. Image processing allowed for collection of pixel information based on intensity or location for statistical analyses. Concurrent OCT was performed, and fixable fluorescent dextrans were introduced into the eye for histological analysis of angiographically active areas.Aqueous angiography yielded high quality images with segmental patterns (p<0.0001; Kruskal-Wallis test. No single quadrant was consistently identified as the primary quadrant of angiographic signal (p = 0.06-0.86; Kruskal-Wallis test. Regions of high proximal signal did not necessarily correlate with regions of high distal signal. Angiographically positive but not negative areas demonstrated intrascleral lumens on OCT images. Aqueous angiography with fluorescent dextrans led to their trapping in AHO pathways.Aqueous angiography is a real-time and physiologic AHO imaging technique in model eyes.

  12. Characteristics of myocardial perfusion imaging and coronary artery angiography in patients of NIDDM complicated with AMI

    International Nuclear Information System (INIS)

    Zhao Peiqin; Zhao Jinhua; Qin Mingzhao; Dai HaoJie; Zhang Runwu; Xiao Fen

    2001-01-01

    Objective: To investigate the characteristic changes of myocardial perfusion imaging and coronary artery angiography in patients of acute myocardial infarction (AMI) with underlined type 2 diabetes mellitus. Methods: 25 type 2 diabetes mellitus patients were enrolled for having clinical manifestation of AMI. Ten inpatients with AMI of simple coronary heart disease origin were served as controls. All subjects underwent both myocardial perfusion imagings (resting and nitroglycerine invention) and coronary artery angiography. Results: Compared to controls (40%), type 2 diabetes mellitus + AMI group had higher rate of multivessel disease (60%). For type 2 diabetes mellitus + AMI patients, 129/400 segments (32.25%) showed fixed defect, 25/160 segments (15.62%) in controls. Conclusions: For type 2 diabetes mellitus + AMI group, myocardial perfusion defects are widely distributed and multivessel or severe stenosis is more often presented. Good correlation exists between abnormal segments and angiographic lesions in both the number of segments involved and the severity of the lesions. Radionuclide myocardial perfusion is therefore considered a useful screening test not inferior to angiography, especially for those who are not tolerant enough to undergoing angiography

  13. A framework of region-based dynamic image fusion

    Institute of Scientific and Technical Information of China (English)

    WANG Zhong-hua; QIN Zheng; LIU Yu

    2007-01-01

    A new framework of region-based dynamic image fusion is proposed. First, the technique of target detection is applied to dynamic images (image sequences) to segment images into different targets and background regions. Then different fusion rules are employed in different regions so that the target information is preserved as much as possible. In addition, steerable non-separable wavelet frame transform is used in the process of multi-resolution analysis, so the system achieves favorable characters of orientation and invariant shift. Compared with other image fusion methods, experimental results showed that the proposed method has better capabilities of target recognition and preserves clear background information.

  14. Multi-sensor image fusion and its applications

    CERN Document Server

    Blum, Rick S

    2005-01-01

    Taking another lesson from nature, the latest advances in image processing technology seek to combine image data from several diverse types of sensors in order to obtain a more accurate view of the scene: very much the same as we rely on our five senses. Multi-Sensor Image Fusion and Its Applications is the first text dedicated to the theory and practice of the registration and fusion of image data, covering such approaches as statistical methods, color-related techniques, model-based methods, and visual information display strategies.After a review of state-of-the-art image fusion techniques,

  15. Geophysical data fusion for subsurface imaging

    International Nuclear Information System (INIS)

    Hoekstra, P.; Vandergraft, J.; Blohm, M.; Porter, D.

    1993-08-01

    A geophysical data fusion methodology is under development to combine data from complementary geophysical sensors and incorporate geophysical understanding to obtain three dimensional images of the subsurface. The research reported here is the first phase of a three phase project. The project focuses on the characterization of thin clay lenses (aquitards) in a highly stratified sand and clay coastal geology to depths of up to 300 feet. The sensor suite used in this work includes time-domain electromagnetic induction (TDEM) and near surface seismic techniques. During this first phase of the project, enhancements to the acquisition and processing of TDEM data were studied, by use of simulated data, to assess improvements for the detection of thin clay layers. Secondly, studies were made of the use of compressional wave and shear wave seismic reflection data by using state-of-the-art high frequency vibrator technology. Finally, a newly developed processing technique, called ''data fusion,'' was implemented to process the geophysical data, and to incorporate a mathematical model of the subsurface strata. Examples are given of the results when applied to real seismic data collected at Hanford, WA, and for simulated data based on the geology of the Savannah River Site

  16. Clinical advances in cardiovascular magnetic resonace imaging and angiography

    NARCIS (Netherlands)

    Bosch, van den H.C.M.

    2018-01-01

    Cardiovascular magnetic resonance imaging is an important noninvasive imaging modality for the diagnosis, clinical work‐up and treatment planning in patients suspected for a wide range of cardiovascular pathology. CMR imaging is accurate and reliable, and provides invaluable information to evaluate

  17. Fast single image dehazing based on image fusion

    Science.gov (United States)

    Liu, Haibo; Yang, Jie; Wu, Zhengping; Zhang, Qingnian

    2015-01-01

    Images captured in foggy weather conditions often fade the colors and reduce the contrast of the observed objects. An efficient image fusion method is proposed to remove haze from a single input image. First, the initial medium transmission is estimated based on the dark channel prior. Second, the method adopts an assumption that the degradation level affected by haze of each region is the same, which is similar to the Retinex theory, and uses a simple Gaussian filter to get the coarse medium transmission. Then, pixel-level fusion is achieved between the initial medium transmission and coarse medium transmission. The proposed method can recover a high-quality haze-free image based on the physical model, and the complexity of the proposed method is only a linear function of the number of input image pixels. Experimental results demonstrate that the proposed method can allow a very fast implementation and achieve better restoration for visibility and color fidelity compared to some state-of-the-art methods.

  18. Imaging choroidal neovascular membrane using en face swept-source optical coherence tomography angiography

    Directory of Open Access Journals (Sweden)

    Moussa M

    2017-10-01

    Full Text Available Magdy Moussa,1,2 Mahmoud Leila,3 Hagar Khalid1,2 1Ophthalmology Department, Faculty of Medicine, Tanta University, Tanta, Egypt; 2MEDIC Eye Center, Tanta, Egypt; 3Retina Department, Research Institute of Ophthalmology, Giza, Egypt Purpose: The aim of this study was to assess the efficacy of swept-source optical coherence tomography angiography (SS-OCTA in delineating the morphology of choroidal neovascular membrane (CNV. Patients and methods: This was a retrospective observational case series reviewing clinical data and fundus fluorescein angiography (FFA, swept-source optical coherence tomography (SS-OCT, and SS-OCTA images of patients with CNV and comparing the findings. The swept-source technology enables deeper penetration and superior axial resolution. The incorporated blood flow detection algorithm, optical coherence tomography angiography ratio analysis (OCTARA, enables visualization of CNV in vivo without the need for dye injection. Results: The study included 136 eyes of 105 patients. Active lesions on SS-OCTA images showed increased capillary density, extensive arborization, vascular anastomosis and looping, and peri-lesional hollow. Inactive lesions showed decreased capillary density, presence of large linear vessels, and presence of feeder vessels supplying the CNV. We detected positive correlation between SS-OCTA, FFA, and SS-OCT images in 97% of eyes. In the remaining 3%, SS-OCTA confirmed the absence of CNV, whereas FFA and SS-OCT either were inconclusive in the diagnosis of CNV or yielded false-positive results. Conclusion: SS-OCT and SS-OCTA represent a reproducible risk-free analog for FFA in imaging CNV. SS-OCTA is particularly versatile in cases where FFA and SS-OCT are inconclusive. Keywords: swept-source OCT, OCT angiography, imaging of CNV, OCTARA algorithm

  19. Remote sensing image fusion in the context of Digital Earth

    International Nuclear Information System (INIS)

    Pohl, C

    2014-01-01

    The increase in the number of operational Earth observation satellites gives remote sensing image fusion a new boost. As a powerful tool to integrate images from different sensors it enables multi-scale, multi-temporal and multi-source information extraction. Image fusion aims at providing results that cannot be obtained from a single data source alone. Instead it enables feature and information mining of higher reliability and availability. The process required to prepare remote sensing images for image fusion comprises most of the necessary steps to feed the database of Digital Earth. The virtual representation of the planet uses data and information that is referenced and corrected to suit interpretation and decision-making. The same pre-requisite is valid for image fusion, the outcome of which can directly flow into a geographical information system. The assessment and description of the quality of the results remains critical. Depending on the application and information to be extracted from multi-source images different approaches are necessary. This paper describes the process of image fusion based on a fusion and classification experiment, explains the necessary quality measures involved and shows with this example which criteria have to be considered if the results of image fusion are going to be used in Digital Earth

  20. MR angiography of eddy-current-free MR imaging system with a 3T permanent magnet

    International Nuclear Information System (INIS)

    Nishimura, H.; Watanabe, S.; Takeuchi, H.

    1991-01-01

    This paper reports that, the authors main purpose was to evaluate two-dimensional time flight MR angiography in the visualization of vascular structure by using an eddy-current-free 0.3-T permanent magnet MR imaging system. The authors have developed multisection acquisition technique for two-dimensional time-of-flight MR angiography with the use of velocity-compensated gradient echoes. MR angiograms were obtained with a ray-tracing algorithm of the new modified maximum intensity projection at various viewing angles. These angiograms are displayed on cathode-ray tubes in a high-speed cyclic mode to depict the front-rear relation of vessels for better recognition. With an eddy-current-free permanent magnet system, two-dimensional time-of-flight angiography could clearly depict intracranial vascular structure, cervical vessels, and vessels of the extremities with thin-section (2 or 3 mm) acquisition. A high flip angle (90 degrees) with a short TR enabled better differentiation between blood flow and stationary tissues. Stenosis of the carotids could be detected in accordance with digital subtraction angiography

  1. Advances in fusion of PET, SPET, CT und MRT images

    International Nuclear Information System (INIS)

    Pietrzyk, U.

    2003-01-01

    Image fusion as part of the correlative analysis for medical images has gained ever more interest and the fact that combined systems for PET and CT are commercially available demonstrates the importance for medical diagnostics, therapy and research oriented applications. In this work the basics of image registration, its different strategies and the mathematical and physical background are described. A successful image registration is an essential prerequisite for the next steps, namely correlative medical image analysis. Means to verify image registration and the different modes for integrated display are presented and its usefulness is discussed. Possible limitations in applying image fusion in order to avoid misinterpretation will be pointed out. (orig.) [de

  2. Craniofacial duplication (diprosopus): CT, MR imaging, and MR angiography findings case report.

    Science.gov (United States)

    Hähnel, Stefan; Schramm, Peter; Hassfeld, Stefan; Steiner, Hans H; Seitz, Angelika

    2003-01-01

    Diprosopus is one of the rarest malformations in humans. In addition to the facial structures, the cerebral frontal lobes were duplicated in this case. Three pairs of anterior cerebral arteries were detected, and the rostral parts of the superior sagittal sinus were duplicated. Computed tomography, magnetic resonance (MR) imaging, and MR angiography allowed study of the degree of duplicative changes in diprosopus, especially for planning cosmetic correction. Copyright RSNA, 2002

  3. Imaging of the ventricular septal wall and the portal vein by digital subtraction angiography

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Kyoichi; Harashima, Haruhiko; Yamada, Hiromi; Hiraishi, Takahisa; Mikami, Fumio [National Medical Center of Hospital, Tokyo (Japan)

    1983-06-01

    Digital subtraction angiography (DSA) was performed in 2 cases of hypertrophic cardiomyopathy and 2 cases of portal vein disorder. In hypertrophic cardiomyopathy, DSA with the infusion of isopaque 370 at the speed of 5 to 7 ml/sec produced the image of the ventricular septal wall, showing a small ejection fraction. Of portal vein disorders, DSA revealed the portal vein and was helpful in diagnosing tumoral thrombosis of the portal vein in a case of liver carcinoma and portal hypertension.

  4. Imaging of Acute Mesenteric Ischemia Using Multidetector CT and CT Angiography in a Porcine Model

    OpenAIRE

    Rosow, David E.; Sahani, Dushyant; Strobel, Oliver; Kalva, Sanjeeva; Mino-Kenudson, Mari; Holalkere, Nagaraj S.; Alsfasser, Guido; Saini, Sanjay; Lee, Susanna I.; Mueller, Peter R.; Castillo, Carlos Fernández-del; Warshaw, Andrew L.; Thayer, Sarah P.

    2005-01-01

    Acute mesenteric ischemia, a frequently lethal disease, requires prompt diagnosis and intervention for favorable clinical outcomes. This goal remains elusive due, in part, to lack of a noninvasive and accurate imaging study. Traditional angiography is the diagnostic gold standard but is invasive and costly. Computed tomography (CT) is readily available and noninvasive but has shown variable success in diagnosing this disease. The faster scanning time of multidetector row CT (M.D.CT) greatly f...

  5. Coronary artery bypass graft imaging using ECG-gated multislice computed tomography: Comparison with catheter angiography

    International Nuclear Information System (INIS)

    Moore, R.K.G.; Sampson, C.; MacDonald, S.; Moynahan, C.; Groves, D.; Chester, M.R.

    2005-01-01

    AIM: To compare the value of multislice computerized tomography (MSCT) in imaging coronary artery bypass grafts (CABGs) by direct quantitative comparison with standard invasive angiography. METHODS: Using MSCT, 50 consecutive patients who had previously undergone CABG surgery and had recently undergone invasive angiography for recurrent angina pectoris, were studied further using MSCT after intravenous injection of non-ionic contrast agent; cardiac imaging was performed during a single breath-hold. Graft anatomy was quantified, using both quantitative coronary angiography (QCA) and MSCT, by different investigators blinded to each other. Reproducibility was quantified using the standard error of the measurement expressed as a percentage in log-transformed values (CV%) and intraclass correlation (ICC). RESULTS: All 150 grafts were imaged using MSCT; only 4 patent grafts were not imaged using selective angiography. Good agreement was achieved between MSCT and QCA on assessment of proximal anastomoses (CV% 25.2, ICC 0.84), mid-vessel luminal diameter (CV% 15.5, ICC 0.91) and aneurysmal dilations (CV% 14.3). Reasonable agreement was reached on assessment of distal anastomoses (CV% 26.7, ICC 0.66) and categorization of distal run-off (ICC 0.73). Good agreement was observed for stenoses of over 50% luminal loss (CV% 8.7, ICC 0.97) but agreement on assessment of less severe lesions was poor (CV% 208.7, ICC 0.51). CONCLUSION: This study demonstrates that CABGs can be quantitatively evaluated using MSCT, and that significant lesions present in all CABG segments can be reliably identified. Agreement between MSCT and QCA for lesions of less than 50% luminal loss was poor

  6. Coronary artery bypass graft imaging using ECG-gated multislice computed tomography: Comparison with catheter angiography

    Energy Technology Data Exchange (ETDEWEB)

    Moore, R.K.G. [Cardiothoracic Centre, Liverpool (United Kingdom)]. E-mail: moore@roger.go-legend.net; Sampson, C. [Cardiothoracic Centre, Liverpool (United Kingdom); MacDonald, S. [Cardiothoracic Centre, Liverpool (United Kingdom); Moynahan, C. [Cardiothoracic Centre, Liverpool (United Kingdom); Groves, D. [National Refractory Angina Centre, Liverpool (United Kingdom); Chester, M.R. [National Refractory Angina Centre, Liverpool (United Kingdom)

    2005-09-01

    AIM: To compare the value of multislice computerized tomography (MSCT) in imaging coronary artery bypass grafts (CABGs) by direct quantitative comparison with standard invasive angiography. METHODS: Using MSCT, 50 consecutive patients who had previously undergone CABG surgery and had recently undergone invasive angiography for recurrent angina pectoris, were studied further using MSCT after intravenous injection of non-ionic contrast agent; cardiac imaging was performed during a single breath-hold. Graft anatomy was quantified, using both quantitative coronary angiography (QCA) and MSCT, by different investigators blinded to each other. Reproducibility was quantified using the standard error of the measurement expressed as a percentage in log-transformed values (CV%) and intraclass correlation (ICC). RESULTS: All 150 grafts were imaged using MSCT; only 4 patent grafts were not imaged using selective angiography. Good agreement was achieved between MSCT and QCA on assessment of proximal anastomoses (CV% 25.2, ICC 0.84), mid-vessel luminal diameter (CV% 15.5, ICC 0.91) and aneurysmal dilations (CV% 14.3). Reasonable agreement was reached on assessment of distal anastomoses (CV% 26.7, ICC 0.66) and categorization of distal run-off (ICC 0.73). Good agreement was observed for stenoses of over 50% luminal loss (CV% 8.7, ICC 0.97) but agreement on assessment of less severe lesions was poor (CV% 208.7, ICC 0.51). CONCLUSION: This study demonstrates that CABGs can be quantitatively evaluated using MSCT, and that significant lesions present in all CABG segments can be reliably identified. Agreement between MSCT and QCA for lesions of less than 50% luminal loss was poor.

  7. Testicular radionuclide angiography and sttatic imaging: anatomy, scintigraphic interpretation, and clinical indications

    International Nuclear Information System (INIS)

    Holder, L.E.; Martire, J.R.; Holmes, E.R. III.; Wagner, H.N. Jr.

    1977-01-01

    Radionuclide testicular angiography and static imaging is an easy, rapidly performed study. Its usefulness in separating acute testicular torsion from acute epididymitis has been confirmed. Increased angiographic perfusion with definition of the testicular and deferential arteries in the spermatic cord and the pudendal artery posteriorly is equated with inflammation. Intense increased vascularity on the blood pool image is seen in abscess and acute inflammation, while cases of tumor and trauma have mild increases. Acute or missed testicular torsion, uncomplicated hydroceles, and spermatoceles show absent vascularity. On the static images, decreased activity is characteristic of the shape and location of the avascular structure. Technical factors are stressed

  8. Angiography in angiology

    International Nuclear Information System (INIS)

    Zeitler, E.; Grosse-Vorholt, R.

    1980-01-01

    A review is given of recent developments in angiography including advances in the equipment, in the technique and in image processing. Indications for and interpretation of angiography are discussed and angiographic-therapeutic procedures are considered. (C.F.)

  9. Angle-independent measure of motion for image-based gating in 3D coronary angiography

    International Nuclear Information System (INIS)

    Lehmann, Glen C.; Holdsworth, David W.; Drangova, Maria

    2006-01-01

    The role of three-dimensional (3D) image guidance for interventional procedures and minimally invasive surgeries is increasing for the treatment of vascular disease. Currently, most interventional procedures are guided by two-dimensional x-ray angiography, but computed rotational angiography has the potential to provide 3D geometric information about the coronary arteries. The creation of 3D angiographic images of the coronary arteries requires synchronization of data acquisition with respect to the cardiac cycle, in order to minimize motion artifacts. This can be achieved by inferring the extent of motion from a patient's electrocardiogram (ECG) signal. However, a direct measurement of motion (from the 2D angiograms) has the potential to improve the 3D angiographic images by ensuring that only projections acquired during periods of minimal motion are included in the reconstruction. This paper presents an image-based metric for measuring the extent of motion in 2D x-ray angiographic images. Adaptive histogram equalization was applied to projection images to increase the sharpness of coronary arteries and the superior-inferior component of the weighted centroid (SIC) was measured. The SIC constitutes an image-based metric that can be used to track vessel motion, independent of apparent motion induced by the rotational acquisition. To evaluate the technique, six consecutive patients scheduled for routine coronary angiography procedures were studied. We compared the end of the SIC rest period (ρ) to R-waves (R) detected in the patient's ECG and found a mean difference of 14±80 ms. Two simultaneous angular positions were acquired and ρ was detected for each position. There was no statistically significant difference (P=0.79) between ρ in the two simultaneously acquired angular positions. Thus we have shown the SIC to be independent of view angle, which is critical for rotational angiography. A preliminary image-based gating strategy that employed the SIC was

  10. Algorithms for the Analysis of 3D Magnetic Resonance Angiography Images

    International Nuclear Information System (INIS)

    Tizon, Xavier

    2004-01-01

    Atherosclerosis is a disease of the arterial wall, progressively impairing blood flow as it spreads throughout the body. The heart attacks and strokes that result of this condition cause more deaths than cancer in industrial countries. Angiography refers to the group of imaging techniques used through the diagnosis, treatment planning and follow-up of atherosclerosis. In recent years, Magnetic Resonance Angiography (MRA) has shown promising abilities to supplant conventional, invasive, X-ray-based angiography. In order to fully benefit from this modality, there is a need for more objective and reproducible methods. This thesis shows, in two applications, how computerized image analysis can help define and implement these methods. First, by using segmentation to improve visualization of blood-pool contrast enhanced (CE)-MRA, with an additional application in coronary Computerized Tomographic Angiography. We show that, using a limited amount of user interaction and an algorithmic framework borrowed from graph theory and fuzzy logic theory, we can simplify the display of complex 3D structures like vessels. Second, by proposing a methodology to analyze the geometry of arteries in whole-body CE-MRA. The vessel centreline is extracted, and geometrical properties of this 3D curve are measured, to improve interpretation of the angiograms. It represents a more global approach than the conventional evaluation of atherosclerosis, as a first step towards screening for vascular diseases. We have developed the methods presented in this thesis with clinical practice in mind. However, they have the potential to be useful to other applications of computerized image analysis

  11. Free and open-source software application for the evaluation of coronary computed tomography angiography images.

    Science.gov (United States)

    Hadlich, Marcelo Souza; Oliveira, Gláucia Maria Moraes; Feijóo, Raúl A; Azevedo, Clerio F; Tura, Bernardo Rangel; Ziemer, Paulo Gustavo Portela; Blanco, Pablo Javier; Pina, Gustavo; Meira, Márcio; Souza e Silva, Nelson Albuquerque de

    2012-10-01

    The standardization of images used in Medicine in 1993 was performed using the DICOM (Digital Imaging and Communications in Medicine) standard. Several tests use this standard and it is increasingly necessary to design software applications capable of handling this type of image; however, these software applications are not usually free and open-source, and this fact hinders their adjustment to most diverse interests. To develop and validate a free and open-source software application capable of handling DICOM coronary computed tomography angiography images. We developed and tested the ImageLab software in the evaluation of 100 tests randomly selected from a database. We carried out 600 tests divided between two observers using ImageLab and another software sold with Philips Brilliance computed tomography appliances in the evaluation of coronary lesions and plaques around the left main coronary artery (LMCA) and the anterior descending artery (ADA). To evaluate intraobserver, interobserver and intersoftware agreements, we used simple and kappa statistics agreements. The agreements observed between software applications were generally classified as substantial or almost perfect in most comparisons. The ImageLab software agreed with the Philips software in the evaluation of coronary computed tomography angiography tests, especially in patients without lesions, with lesions 70% in the ADA was lower, but this is also observed when the anatomical reference standard is used.

  12. The increased use of computed tomography angiography and magnetic resonance angiography as the sole imaging modalities prior to infrainguinal bypass has had no effect on outcomes.

    Science.gov (United States)

    Shue, Bing; Damle, Rachelle N; Flahive, Julie; Kalish, Jeffrey A; Stone, David H; Patel, Virendra I; Schanzer, Andres; Baril, Donald T

    2015-08-01

    Angiography remains the gold standard imaging modality before infrainguinal bypass. Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) have emerged as noninvasive alternatives for preoperative imaging. We sought to examine contemporary trends in the utilization of CTA and MRA as isolated imaging modalities before infrainguinal bypass and to compare outcomes following infrainguinal bypass in patients who underwent CTA or MRA versus those who underwent conventional arteriography. Patients undergoing infrainguinal bypass within the Vascular Study Group of New England were identified (2003-2012). Patients were stratified by preoperative imaging modality: CTA/MRA alone or conventional angiography. Trends in utilization of these modalities were examined and demographics of these groups were compared. Primary end points included primary patency, secondary patency, and major adverse limb events (MALE) at 1 year as determined by Kaplan-Meier analysis. Multivariable Cox proportional hazards models were constructed to evaluate the effect of imaging modality on primary patency, secondary patency, and MALE after adjusting for confounders. In 3123 infrainguinal bypasses, CTA/MRA alone was used in 462 cases (15%) and angiography was used in 2661 cases (85%). Use of CTA/MRA alone increased over time, with 52 (11%) bypasses performed between 2003 and 2005, 189 (41%) bypasses performed between 2006 and 2009, and 221 (48%) bypasses performed between 2010 and 2012 (P < 0.001). Patients with CTA/MRA alone, compared with patients with angiography, more frequently underwent bypass for claudication (33% vs. 26%, P = 0.001) or acute limb ischemia (13% vs. 5%, P < 0.0001), more frequently had prosthetic conduits (39% vs. 30%, P = 0.001), and less frequently had tibial/pedal targets (32% vs. 40%, P = 0.002). After adjusting for these and other confounders, multivariable analysis demonstrated that the use of CTA/MRA alone was not associated with a significant

  13. Fusion of multispectral and panchromatic images using multirate filter banks

    Institute of Scientific and Technical Information of China (English)

    Wang Hong; Jing Zhongliang; Li Jianxun

    2005-01-01

    In this paper, an image fusion method based on the filter banks is proposed for merging a high-resolution panchromatic image and a low-resolution multispectral image. Firstly, the filter banks are designed to merge different signals with minimum distortion by using cosine modulation. Then, the filter banks-based image fusion is adopted to obtain a high-resolution multispectral image that combines the spectral characteristic of low-resolution data with the spatial resolution of the panchromatic image. Finally, two different experiments and corresponding performance analysis are presented. Experimental results indicate that the proposed approach outperforms the HIS transform, discrete wavelet transform and discrete wavelet frame.

  14. Neutron imaging for inertial confinement fusion and molecular optic imaging

    International Nuclear Information System (INIS)

    Delage, O.

    2010-01-01

    Scientific domains that require imaging of micrometric/nano-metric objects are dramatically increasing (Plasma Physics, Astrophysics, Biotechnology, Earth Sciences...). Difficulties encountered in imaging smaller and smaller objects make this research area more and more challenging and in constant evolution. The two scientific domains, through which this study has been led, are the neutron imaging in the context of the inertial confinement fusion and the fluorescence molecular imaging. Work presented in this thesis has two main objectives. The first one is to describe the instrumentation characteristics that require such imagery and, relatively to the scientific domains considered, identify parameters likely to optimize the imaging system accuracy. The second one is to present the developed data analysis and reconstruction methods able to provide spatial resolution adapted to the size of the observed object. Similarities of numerical algorithms used in these two scientific domains, which goals are quiet different, show how micrometric/nano-metric object imaging is a research area at the border of a large number of scientific disciplines. (author)

  15. Fusion of colour and monochromatic images with edge emphasis

    Directory of Open Access Journals (Sweden)

    Rade M. Pavlović

    2014-02-01

    Full Text Available We propose a novel method to fuse true colour images with monochromatic non-visible range images that seeks to encode important structural information from monochromatic images efficiently but also preserve the natural appearance of the available true chromacity information. We utilise the β colour opponency channel of the lαβ colour as the domain to fuse information from the monochromatic input into the colour input by the way of robust grayscale fusion. This is followed by an effective gradient structure visualisation step that enhances the visibility of monochromatic information in the final colour fused image. Images fused using this method preserve their natural appearance and chromacity better than conventional methods while at the same time clearly encode structural information from the monochormatic input. This is demonstrated on a number of well-known true colour fusion examples and confirmed by the results of subjective trials on the data from several colour fusion scenarios. Introduction The goal of image fusion can be broadly defined as: the representation of visual information contained in a number of input images into a single fused image without distortion or loss of information. In practice, however, a representation of all available information from multiple inputs in a single image is almost impossible and fusion is generally a data reduction task.  One of the sensors usually provides a true colour image that by definition has all of its data dimensions already populated by the spatial and chromatic information. Fusing such images with information from monochromatic inputs in a conventional manner can severely affect natural appearance of the fused image. This is a difficult problem and partly the reason why colour fusion received only a fraction of the attention than better behaved grayscale fusion even long after colour sensors became widespread. Fusion method Humans tend to see colours as contrasts between opponent

  16. A new hyperspectral image compression paradigm based on fusion

    Science.gov (United States)

    Guerra, Raúl; Melián, José; López, Sebastián.; Sarmiento, Roberto

    2016-10-01

    The on-board compression of remote sensed hyperspectral images is an important task nowadays. One of the main difficulties is that the compression of these images must be performed in the satellite which carries the hyperspectral sensor. Hence, this process must be performed by space qualified hardware, having area, power and speed limitations. Moreover, it is important to achieve high compression ratios without compromising the quality of the decompress image. In this manuscript we proposed a new methodology for compressing hyperspectral images based on hyperspectral image fusion concepts. The proposed compression process has two independent steps. The first one is to spatially degrade the remote sensed hyperspectral image to obtain a low resolution hyperspectral image. The second step is to spectrally degrade the remote sensed hyperspectral image to obtain a high resolution multispectral image. These two degraded images are then send to the earth surface, where they must be fused using a fusion algorithm for hyperspectral and multispectral image, in order to recover the remote sensed hyperspectral image. The main advantage of the proposed methodology for compressing remote sensed hyperspectral images is that the compression process, which must be performed on-board, becomes very simple, being the fusion process used to reconstruct image the more complex one. An extra advantage is that the compression ratio can be fixed in advanced. Many simulations have been performed using different fusion algorithms and different methodologies for degrading the hyperspectral image. The results obtained in the simulations performed corroborate the benefits of the proposed methodology.

  17. The optimal algorithm for Multi-source RS image fusion.

    Science.gov (United States)

    Fu, Wei; Huang, Shui-Guang; Li, Zeng-Shun; Shen, Hao; Li, Jun-Shuai; Wang, Peng-Yuan

    2016-01-01

    In order to solve the issue which the fusion rules cannot be self-adaptively adjusted by using available fusion methods according to the subsequent processing requirements of Remote Sensing (RS) image, this paper puts forward GSDA (genetic-iterative self-organizing data analysis algorithm) by integrating the merit of genetic arithmetic together with the advantage of iterative self-organizing data analysis algorithm for multi-source RS image fusion. The proposed algorithm considers the wavelet transform of the translation invariance as the model operator, also regards the contrast pyramid conversion as the observed operator. The algorithm then designs the objective function by taking use of the weighted sum of evaluation indices, and optimizes the objective function by employing GSDA so as to get a higher resolution of RS image. As discussed above, the bullet points of the text are summarized as follows.•The contribution proposes the iterative self-organizing data analysis algorithm for multi-source RS image fusion.•This article presents GSDA algorithm for the self-adaptively adjustment of the fusion rules.•This text comes up with the model operator and the observed operator as the fusion scheme of RS image based on GSDA. The proposed algorithm opens up a novel algorithmic pathway for multi-source RS image fusion by means of GSDA.

  18. Multifocus Image Fusion in Q-Shift DTCWT Domain Using Various Fusion Rules

    Directory of Open Access Journals (Sweden)

    Yingzhong Tian

    2016-01-01

    Full Text Available Multifocus image fusion is a process that integrates partially focused image sequence into a fused image which is focused everywhere, with multiple methods proposed in the past decades. The Dual Tree Complex Wavelet Transform (DTCWT is one of the most precise ones eliminating two main defects caused by the Discrete Wavelet Transform (DWT. Q-shift DTCWT was proposed afterwards to simplify the construction of filters in DTCWT, producing better fusion effects. A different image fusion strategy based on Q-shift DTCWT is presented in this work. According to the strategy, firstly, each image is decomposed into low and high frequency coefficients, which are, respectively, fused by using different rules, and then various fusion rules are innovatively combined in Q-shift DTCWT, such as the Neighborhood Variant Maximum Selectivity (NVMS and the Sum Modified Laplacian (SML. Finally, the fused coefficients could be well extracted from the source images and reconstructed to produce one fully focused image. This strategy is verified visually and quantitatively with several existing fusion methods based on a plenty of experiments and yields good results both on standard images and on microscopic images. Hence, we can draw the conclusion that the rule of NVMS is better than others after Q-shift DTCWT.

  19. Imaging of peripheral arteries by 16-slice computed tomography angiography: a valuable tool

    International Nuclear Information System (INIS)

    Mishra, A.; Ehtuish, Ehtuish F.

    2007-01-01

    To evaluate the efficacy of multidetector (16-row) computed tomography (MDCT) in imaging the upper and lower limb arterial tree in trauma and peripheral vascular disease. Thirty three patients underwent multislice computed tomography angiography (MSCTA) of the upper or the lower limb on multislice (16-slice) CT scanner between November 2004 and July 2005 in the Department of Radiology, National Organ Transplant Center, Tripoli, Libya. The findings were retrospectively compared with the surgical outcome in cases of trauma with suspected arterial injuries; or color Doppler correlation was obtained, for patients of peripheral vascular disease. Multislice computed tomography angiography allows a comprehensive diagnostic work-up in all trauma cases with suspected arterial injuries. In 23 cases of peripheral vascular diseases, MSCTA adequately demonstrated the presence of any stenosis or occlusion, its degree and extent, the presence of collaterals and distal reformation if any; the presence of plaques. Our experience of computed tomography angiography with 16-row MDCT scanner has clearly demonstrated its efficacy as a promising, new, fast, accurate, safe and non-invasive imaging modality of choice in cases of trauma with suspected arterial injuries; and as a useful screening modality in cases of peripheral vascular disease for diagnosis and for grading. (author)

  20. Imaging of acute mesenteric ischemia using multidetector CT and CT angiography in a porcine model.

    Science.gov (United States)

    Rosow, David E; Sahani, Dushyant; Strobel, Oliver; Kalva, Sanjeeva; Mino-Kenudson, Mari; Holalkere, Nagaraj S; Alsfasser, Guido; Saini, Sanjay; Lee, Susanna I; Mueller, Peter R; Fernández-del Castillo, Carlos; Warshaw, Andrew L; Thayer, Sarah P

    2005-12-01

    Acute mesenteric ischemia, a frequently lethal disease, requires prompt diagnosis and intervention for favorable clinical outcomes. This goal remains elusive due, in part, to lack of a noninvasive and accurate imaging study. Traditional angiography is the diagnostic gold standard but is invasive and costly. Computed tomography (CT) is readily available and noninvasive but has shown variable success in diagnosing this disease. The faster scanning time of multidetector row CT (M.D.CT) greatly facilitates the use of CT angiography (CTA) in the clinical setting. We sought to determine whether M.D.CT-CTA could accurately demonstrate vascular anatomy and capture the earliest stages of mesenteric ischemia in a porcine model. Pigs underwent embolization of branches of the superior mesenteric artery, then imaging by M.D.CT-CTA with three-dimensional reconstruction protocols. After scanning, diseased bowel segments were surgically resected and pathologically examined. Multidetector row CT and CT angiography reliably defined normal and occluded mesenteric vessels in the pig. It detected early changes of ischemia including poor arterial enhancement and venous dilatation, which were seen in all ischemic animals. The radiographic findings--compared with pathologic diagnoses-- predicted ischemia, with a positive predictive value of 92%. These results indicate that M.D.CT-CTA holds great promise for the early detection necessary for successful treatment of acute mesenteric ischemia.

  1. CT coronary angiography: Influence of different cardiac reconstruction intervals on image quality and diagnostic accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Dewey, Marc [Department of Radiology, Charite Medical School, Humboldt-Universitaet zu Berlin (Germany)], E-mail: marc.dewey@charite.de; Teige, Florian [Department of Radiology, Charite Medical School, Humboldt-Universitaet zu Berlin (Germany); Rutsch, Wolfgang [Department of Cardiology, Charite Medical School, Humboldt-Universitaet zu Berlin (Germany)], E-mail: wolfgang.rutsch@charite.de; Schink, Tania [Department of Medical Biometry, Charite Medical School, Humboldt-Universitaet zu Berlin (Germany)], E-mail: peter.martus@charite.de; Hamm, Bernd [Department of Radiology, Charite Medical School, Humboldt-Universitaet zu Berlin (Germany)

    2008-07-15

    Purpose: To prospectively analyze image quality and diagnostic accuracy of different reconstruction intervals of coronary angiography using multislice computed tomography (MSCT). Materials and methods: For each of 47 patients, 10 ECG-gated MSCT reconstructions were generated throughout the RR interval from 0 to 90%, resulting in altogether 470 datasets. These datasets were randomly analyzed for image quality and accuracy and compared with conventional angiography. Statistical comparison of intervals was performed using nonparametric analysis for repeated measurements to account for clustering of arteries within patients. Results: Image reconstruction intervals centered at 80, 70, and 40% of the RR interval resulted (in that order) in the best overall image quality for all four main coronary vessels. Eighty percent reconstructions also yielded the highest diagnostic accuracy of all intervals. The combination of the three best intervals (80, 70, and 40%) significantly reduced the nondiagnostic rate as compared with 80% alone (p = 0.005). However, the optimal reconstruction interval combination achieved significantly improved specificities and nondiagnostic rates (p < 0.05). The optimal combination consisted of 1.7 {+-} 0.9 reconstruction intervals on average. In approximately half of the patients (49%, 23/47) a single reconstruction was optimal. In 18 (38%), 3 (6%), and 3 (6%) patients one, two, and three additional reconstruction intervals were required, respectively, to achieve optimal quality. In 28% of the patients the optimal combination consisted of reconstructions other than the three best intervals (80, 70, and 40%). Conclusion: Multiple image reconstruction intervals are essential to ensure high image quality and accuracy of CT coronary angiography.

  2. MR imaging and MR angiography in preoperative evaluation of intracranial meningiomas

    International Nuclear Information System (INIS)

    Goldmann, A.; Kunz, U.; Bader, C.; Leibing, U.; Friedrich, J.M.; Oldenkott, P.

    1994-01-01

    A group of 41 patients with intracranial meningiomas were examined by MR imaging (MRI) and MR angiography (MRA) to assess the clinical value of MRA in the preoperative evaluation of these patients. The results of MRA were compared with the results of intraarterial cerebral catheter X-ray angiography (XRA; n 19) and with the operative findings (n = 41). Our results showed a good correlation between MRA and XRA/surgery in demonstrating the relationship between the tumor and adjacent venous and arterial structures. Use of MRA was also helpful in demonstrating the degree of intrinsic tumor vascularity. It also supplied important information for operative planning. Adjunct XRA was mandatory if detailed information about tumor-feeding vessels was requested by the neurosurgeon, especially in highly vascularized angiomatous meningiomas and in meningiomas suspected of tumor feeding by vessels of the internal carotid artery. (orig.)

  3. MR imaging and MR angiography in preoperative evaluation of intracranial meningiomas

    Energy Technology Data Exchange (ETDEWEB)

    Goldmann, A. [Dept. of Diagnostic Radiology, Univ. of Ulm (Germany); Kunz, U. [Dept. of Neurosurgery, Military Hospital, Academic Hospital of the University, Ulm (Germany); Bader, C. [Dept. of Diagnostic Radiology, Univ. of Ulm (Germany); Leibing, U. [Dept. of Diagnostic Radiology, Univ. of Ulm (Germany); Friedrich, J.M. [Dept. of Diagnostic Radiology, Univ. of Ulm (Germany); Oldenkott, P. [Dept. of Neurosurgery, Military Hospital, Academic Hospital of the University, Ulm (Germany)

    1994-12-01

    A group of 41 patients with intracranial meningiomas were examined by MR imaging (MRI) and MR angiography (MRA) to assess the clinical value of MRA in the preoperative evaluation of these patients. The results of MRA were compared with the results of intraarterial cerebral catheter X-ray angiography (XRA; n = 19) and with the operative findings (n = 41). Our results showed a good correlation between MRA and XRA/surgery in demonstrating the relationship between the tumor and adjacent venous and arterial structures. Use of MRA was also helpful in demonstrating the degree of intrinsic tumor vascularity. It also supplied important information for operative planning. Adjunct XRA was mandatory if detailed information about tumor-feeding vessels was requested by the neurosurgeon, especially in highly vascularized angiomatous meningiomas and in meningiomas suspected of tumor feeding by vessels of the internal carotid artery. (orig.)

  4. Whole-brain dynamic CT angiography and perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Orrison, W.W. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Department of Medical Education, University of Nevada School of Medicine, Reno, NV (United States); Snyder, K.V.; Hopkins, L.N. [Department of Neurosurgery, Millard Fillmore Gates Circle Hospital, Buffalo, NY (United States); Roach, C.J. [School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Ringdahl, E.N. [Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV (United States); Nazir, R. [Shifa International Hospital, Islamabad (Pakistan); Hanson, E.H., E-mail: eric.hanson@amigenics.co [College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States)

    2011-06-15

    The availability of whole brain computed tomography (CT) perfusion has expanded the opportunities for analysing the haemodynamic parameters associated with varied neurological conditions. Examples demonstrating the clinical utility of whole-brain CT perfusion imaging in selected acute and chronic ischaemic arterial neurovascular conditions are presented. Whole-brain CT perfusion enables the detection and focused haemodynamic analyses of acute and chronic arterial conditions in the central nervous system without the limitation of partial anatomical coverage of the brain.

  5. Catheter Angiography

    Medline Plus

    Full Text Available ... small burst of radiation that passes through the body, recording an image on photographic film or a special detector. Different ... about radiology? Share your patient story here Images × ... Related Articles and Media Angioplasty and Vascular Stenting MR Angiography (MRA) Contrast ...

  6. Catheter Angiography

    Medline Plus

    Full Text Available ... navigation Test/Treatment Patient Type Screening/Wellness Disease/Condition Safety En Español More Info Images/Videos About Us ... the equipment look like? How does the procedure work? How is the ... and treat medical conditions. Angiography uses one of three imaging technologies and, ...

  7. Research on fusion algorithm of polarization image in tetrolet domain

    Science.gov (United States)

    Zhang, Dexiang; Yuan, BaoHong; Zhang, Jingjing

    2015-12-01

    Tetrolets are Haar-type wavelets whose supports are tetrominoes which are shapes made by connecting four equal-sized squares. A fusion method for polarization images based on tetrolet transform is proposed. Firstly, the magnitude of polarization image and angle of polarization image can be decomposed into low-frequency coefficients and high-frequency coefficients with multi-scales and multi-directions using tetrolet transform. For the low-frequency coefficients, the average fusion method is used. According to edge distribution differences in high frequency sub-band images, for the directional high-frequency coefficients are used to select the better coefficients by region spectrum entropy algorithm for fusion. At last the fused image can be obtained by utilizing inverse transform for fused tetrolet coefficients. Experimental results show that the proposed method can detect image features more effectively and the fused image has better subjective visual effect

  8. Catheter Angiography

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Catheter Angiography Catheter angiography uses a catheter, x-ray ... are the limitations of Catheter Angiography? What is Catheter Angiography? Angiography is a minimally invasive medical test ...

  9. Medium resolution image fusion, does it enhance forest structure assessment

    CSIR Research Space (South Africa)

    Roberts, JW

    2008-07-01

    Full Text Available This research explored the potential benefits of fusing optical and Synthetic Aperture Radar (SAR) medium resolution satellite-borne sensor data for forest structural assessment. Image fusion was applied as a means of retaining disparate data...

  10. Dose performance and image quality: Dual source CT versus single source CT in cardiac CT angiography

    International Nuclear Information System (INIS)

    Wang Min; Qi Hengtao; Wang Ximing; Wang Tao; Chen, Jiu-Hong; Liu Cheng

    2009-01-01

    Objective: To evaluate dose performance and image quality of 64-slice dual source CT (DSCT) in comparison to 64-slice single source CT (SSCT) in cardiac CT angiography (CTA). Methods: 100 patients examined by DSCT and 60 patients scanned by SSCT were included in this study. Objective indices such as image noise, contrast-to-noise ratio and signal-to-noise ratio were analyzed. Subjective image quality was assessed by two cardiovascular radiologists in consensus using a four-point scale (1 = excellent to 4 = not acceptable). Estimation of effective dose was performed on the basis of dose length product (DLP). Results: At low heart rates ( 0.05), but, at high heart rates (>70 bpm), DSCT provided robust image quality (P 70 bpm), DSCT is able to provide robust diagnostic image quality at doses far below that of SSCT.

  11. Radar image and data fusion for natural hazards characterisation

    Science.gov (United States)

    Lu, Zhong; Dzurisin, Daniel; Jung, Hyung-Sup; Zhang, Jixian; Zhang, Yonghong

    2010-01-01

    Fusion of synthetic aperture radar (SAR) images through interferometric, polarimetric and tomographic processing provides an all - weather imaging capability to characterise and monitor various natural hazards. This article outlines interferometric synthetic aperture radar (InSAR) processing and products and their utility for natural hazards characterisation, provides an overview of the techniques and applications related to fusion of SAR/InSAR images with optical and other images and highlights the emerging SAR fusion technologies. In addition to providing precise land - surface digital elevation maps, SAR - derived imaging products can map millimetre - scale elevation changes driven by volcanic, seismic and hydrogeologic processes, by landslides and wildfires and other natural hazards. With products derived from the fusion of SAR and other images, scientists can monitor the progress of flooding, estimate water storage changes in wetlands for improved hydrological modelling predictions and assessments of future flood impacts and map vegetation structure on a global scale and monitor its changes due to such processes as fire, volcanic eruption and deforestation. With the availability of SAR images in near real - time from multiple satellites in the near future, the fusion of SAR images with other images and data is playing an increasingly important role in understanding and forecasting natural hazards.

  12. Microembolism after cerebral angiography

    International Nuclear Information System (INIS)

    Manaka, Hiroshi; Sakai, Hideki; Nagata, Izumi

    2000-01-01

    Acute microemboli are detected more precisely with the recently developed diffusion-weighted MR imaging (DWI). We happened to obtain 24 DWIs after 350 diagnostic cerebral angiographies in 1999. DWIs after cerebral angiographies showed bright lesions in 7 patients (28%), of whom 6 had no neurological symptoms after cerebral angiography. Seven of the 24 patients had risk factors for arteriosclerosis. Only one patient had embolic events due to angiography. Microemboli related to cerebral angiographies are inevitable in some patients. Most are silent, however, we should investigate the cause of microemboli and should make cerebral angiography safer. (author)

  13. Neutron penumbral imaging of laser-fusion targets

    International Nuclear Information System (INIS)

    Lerche, R.A.; Ress, D.B.

    1988-01-01

    Using a new technique, penumbral coded-aperture imaging, the first neutron images of laser-driven, inertial-confinement fusion targets were obtained. With these images the deuterium-tritium burn region within a compressed target can be measured directly. 4 references, 11 figures

  14. [A preliminary research on multi-source medical image fusion].

    Science.gov (United States)

    Kang, Yuanyuan; Li, Bin; Tian, Lianfang; Mao, Zongyuan

    2009-04-01

    Multi-modal medical image fusion has important value in clinical diagnosis and treatment. In this paper, the multi-resolution analysis of Daubechies 9/7 Biorthogonal Wavelet Transform is introduced for anatomical and functional image fusion, then a new fusion algorithm with the combination of local standard deviation and energy as texture measurement is presented. At last, a set of quantitative evaluation criteria is given. Experiments show that both anatomical and metabolism information can be obtained effectively, and both the edge and texture features can be reserved successfully. The presented algorithm is more effective than the traditional algorithms.

  15. Reducing Radiation Dose in Coronary Angiography and Angioplasty Using Image Noise Reduction Technology.

    Science.gov (United States)

    Kastrati, Mirlind; Langenbrink, Lukas; Piatkowski, Michal; Michaelsen, Jochen; Reimann, Doris; Hoffmann, Rainer

    2016-08-01

    This study sought to quantitatively evaluate the reduction of radiation dose in coronary angiography and angioplasty with the use of image noise reduction technology in a routine clinical setting. Radiation dose data from consecutive 605 coronary procedures (397 consecutive coronary angiograms and 208 consecutive coronary interventions) performed from October 2014 to April 2015 on a coronary angiography system with noise reduction technology (Allura Clarity IQ) were collected. For comparison, radiation dose data from consecutive 695 coronary procedures (435 coronary angiograms and 260 coronary interventions) performed on a conventional coronary angiography system from October 2013 to April 2014 were evaluated. Patient radiation dosage was evaluated based on the cumulative dose area product. Operators and operator practice did not change between the 2 evaluated periods. Patient characteristics were collected to evaluate similarity of patient groups. Image quality was evaluated on a 5-grade scale in 30 patients of each group. There were no significant differences between the 2 evaluated groups in gender, age, weight, and fluoroscopy time (6.8 ± 6.1 vs 6.9 ± 6.3 minutes, not significant). The dose area product was reduced from 3195 ± 2359 to 983 ± 972 cGycm(2) (65%, p technology. Image quality was graded as similar between the evaluated systems (4.0 ± 0.7 vs 4.2 ± 0.6, not significant). In conclusion, a new x-ray technology with image noise reduction algorithm provides a substantial reduction in radiation exposure without the need to prolong the procedure or fluoroscopy time. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Image enhancement using thermal-visible fusion for human detection

    Science.gov (United States)

    Zaihidee, Ezrinda Mohd; Hawari Ghazali, Kamarul; Zuki Saleh, Mohd

    2017-09-01

    An increased interest in detecting human beings in video surveillance system has emerged in recent years. Multisensory image fusion deserves more research attention due to the capability to improve the visual interpretability of an image. This study proposed fusion techniques for human detection based on multiscale transform using grayscale visual light and infrared images. The samples for this study were taken from online dataset. Both images captured by the two sensors were decomposed into high and low frequency coefficients using Stationary Wavelet Transform (SWT). Hence, the appropriate fusion rule was used to merge the coefficients and finally, the final fused image was obtained by using inverse SWT. From the qualitative and quantitative results, the proposed method is more superior than the two other methods in terms of enhancement of the target region and preservation of details information of the image.

  17. Acute chest pain: The role of MR imaging and MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Hunold, Peter, E-mail: peter.hunold@uk-sh.de [Clinic for Radiology and Nuclear Medicine, University Hospital Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck (Germany); Bischoff, Peter, E-mail: peter.bischoff@uk-sh.de [Clinic for Radiology and Nuclear Medicine, University Hospital Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck (Germany); Barkhausen, Jörg, E-mail: joerg.barkhausen@uk-sh.de [Clinic for Radiology and Nuclear Medicine, University Hospital Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck (Germany); Vogt, Florian M., E-mail: florian.vogt@uk-sh.de [Clinic for Radiology and Nuclear Medicine, University Hospital Schleswig-Holstein, Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck (Germany)

    2012-12-15

    MR imaging (MRI) and MR angiography (MRA) have gained a high level of diagnostic accuracy in cardiovascular disease. MRI in cardiac disease has been established as the non-invasive standard of reference in many pathologies. However, in acute chest pain the situation is somewhat special since many of the patients presenting in the emergency department suffer from potentially life-threatening disease including acute coronary syndrome, pulmonary embolism, and acute aortic syndrome. Those patients need a fast and definitive evaluation under continuous monitoring of vital parameters. Due to those requirements MRI seems to be less suitable compared to X-ray coronary angiography and multislice computed tomography angiography (CTA). However, MRI allows for a comprehensive assessment of all clinically stable patients providing unique information on the cardiovascular system including ischemia, inflammation and function. Furthermore, MRI and MRA are considered the method of choice in patients with contraindications to CTA and for regular follow-up in known aortic disease. This review addresses specific features of MRI and MRA for different cardiovascular conditions presenting with acute chest pain.

  18. CAPILLARY NETWORK ALTERATIONS IN X-LINKED RETINOSCHISIS IMAGED ON OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

    Science.gov (United States)

    Romano, Francesco; Arrigo, Alessandro; Chʼng, Soon Wai; Battaglia Parodi, Maurizio; Manitto, Maria Pia; Martina, Elisabetta; Bandello, Francesco; Stanga, Paulo E

    2018-06-05

    To assess foveal and parafoveal vasculature at the superficial capillary plexus, deep capillary plexus, and choriocapillaris of patients with X-linked retinoschisis by means of optical coherence tomography angiography. Six patients with X-linked retinoschisis (12 eyes) and seven healthy controls (14 eyes) were recruited and underwent complete ophthalmologic examination, including best-corrected visual acuity, dilated fundoscopy, and 3 × 3-mm optical coherence tomography angiography macular scans (DRI OCT Triton; Topcon Corp). After segmentation and quality review, optical coherence tomography angiography slabs were imported into ImageJ 1.50 (NIH; Bethesda) and digitally binarized. Quantification of vessel density was performed after foveal avascular zone area measurement and exclusion. Patients were additionally divided into "responders" and "nonresponders" to dorzolamide therapy. Foveal avascular zone area resulted markedly enlarged at the deep capillary plexus (P < 0.001), particularly in nonresponders. Moreover, patients disclosed a significant deep capillary plexus rarefaction, when compared with controls (P: 0.04); however, a subanalysis revealed that this damage was limited to the fovea (P: 0.006). Finally, the enlargement of foveal avascular zone area positively correlated with a decline in best-corrected visual acuity (P: 0.01). Prominent foveal vascular impairment is detectable in the deep capillary plexus of patients with X-linked retinoschisis. Our results correlate with functional outcomes, suggesting a possible vascular role in X-linked retinoschisis clinical manifestations.

  19. Hybrid Image Fusion for Sharpness Enhancement of Multi-Spectral Lunar Images

    Science.gov (United States)

    Awumah, Anna; Mahanti, Prasun; Robinson, Mark

    2016-10-01

    Image fusion enhances the sharpness of a multi-spectral (MS) image by incorporating spatial details from a higher-resolution panchromatic (Pan) image [1,2]. Known applications of image fusion for planetary images are rare, although image fusion is well-known for its applications to Earth-based remote sensing. In a recent work [3], six different image fusion algorithms were implemented and their performances were verified with images from the Lunar Reconnaissance Orbiter (LRO) Camera. The image fusion procedure obtained a high-resolution multi-spectral (HRMS) product from the LRO Narrow Angle Camera (used as Pan) and LRO Wide Angle Camera (used as MS) images. The results showed that the Intensity-Hue-Saturation (IHS) algorithm results in a high-spatial quality product while the Wavelet-based image fusion algorithm best preserves spectral quality among all the algorithms. In this work we show the results of a hybrid IHS-Wavelet image fusion algorithm when applied to LROC MS images. The hybrid method provides the best HRMS product - both in terms of spatial resolution and preservation of spectral details. Results from hybrid image fusion can enable new science and increase the science return from existing LROC images.[1] Pohl, Cle, and John L. Van Genderen. "Review article multisensor image fusion in remote sensing: concepts, methods and applications." International journal of remote sensing 19.5 (1998): 823-854.[2] Zhang, Yun. "Understanding image fusion." Photogramm. Eng. Remote Sens 70.6 (2004): 657-661.[3] Mahanti, Prasun et al. "Enhancement of spatial resolution of the LROC Wide Angle Camera images." Archives, XXIII ISPRS Congress Archives (2016).

  20. Fusion of Geophysical Images in the Study of Archaeological Sites

    Science.gov (United States)

    Karamitrou, A. A.; Petrou, M.; Tsokas, G. N.

    2011-12-01

    This paper presents results from different fusion techniques between geophysical images from different modalities in order to combine them into one image with higher information content than the two original images independently. The resultant image will be useful for the detection and mapping of buried archaeological relics. The examined archaeological area is situated in Kampana site (NE Greece) near the ancient theater of Maronia city. Archaeological excavations revealed an ancient theater, an aristocratic house and the temple of the ancient Greek God Dionysus. Numerous ceramic objects found in the broader area indicated the probability of the existence of buried urban structure. In order to accurately locate and map the latter, geophysical measurements performed with the use of the magnetic method (vertical gradient of the magnetic field) and of the electrical method (apparent resistivity). We performed a semi-stochastic pixel based registration method between the geophysical images in order to fine register them by correcting their local spatial offsets produced by the use of hand held devices. After this procedure we applied to the registered images three different fusion approaches. Image fusion is a relatively new technique that not only allows integration of different information sources, but also takes advantage of the spatial and spectral resolution as well as the orientation characteristics of each image. We have used three different fusion techniques, fusion with mean values, with wavelets by enhancing selected frequency bands and curvelets giving emphasis at specific bands and angles (according the expecting orientation of the relics). In all three cases the fused images gave significantly better results than each of the original geophysical images separately. The comparison of the results of the three different approaches showed that the fusion with the use of curvelets, giving emphasis at the features' orientation, seems to give the best fused image

  1. Subjective and objective image differences in pediatric computed tomography cardiac angiography using lower iodine concentration

    International Nuclear Information System (INIS)

    Hwang, Jae-Yeon; Choo, Ki Seok; Choi, Yoon Young; Kim, Jin Hyeok; Ryu, Hwaseong; Kim, Yong-Woo; Jeon, Ung Bae; Nam, Kyung Jin; Han, Junhee

    2017-01-01

    Several recent studies showed the optimal contrast enhancement with a low-concentration and iso-osmolar contrast media in both adult and pediatric patients. However, low contrast media concentrations are not routinely used due to concerns of suboptimal enhancement of cardiac structures and small vessels. To evaluate the feasibility of using iso-osmolar contrast media containing a low iodine dose for CT cardiac angiography at 80 kilovolts (kVp) in neonates and infants. The iodixanol 270 group consisted of 79 CT scans and the iopromide 370 group of 62 CT scans in patients ≤1 year old. Objective measurement of the contrast enhancement was analyzed and contrast-to-noise ratios of the ascending aorta and left ventricle were calculated. Regarding subjective measurement, a four-point scale system was devised to evaluate degrees of contrast enhancement, image noise, motion artifact and overall image quality of each image set. Reader performance for correctly differentiating iodixanol 270 and iopromide 370 by visual assessment was evaluated. Group objective and subjective measurements were nonsignificantly different. Overall sensitivity, specificity and diagnostic accuracy for correctly differentiating iodixanol 270 and iopromide 370 by visual assessment were 42.8%, 59%, and 50%, respectively. The application of iodixanol 270 achieved optimal enhancement for performing pediatric cardiac CT angiography at 80 kVp in neonates and infants. Objective measurements of contrast enhancement and subjective image quality assessments were not statistically different in the iodixanol 270 and iopromide 370 groups. (orig.)

  2. Subjective and objective image differences in pediatric computed tomography cardiac angiography using lower iodine concentration

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jae-Yeon [Pusan National University Yangsan Hospital, Department of Radiology, Yangsan-si, Gyeongsangnam-do (Korea, Republic of); Pusan National University Yangsan Hospital, Research Institute for Convergence of Biomedical Science and Technology, Yangsan-si, Gyeongsangnam-do (Korea, Republic of); Choo, Ki Seok; Choi, Yoon Young; Kim, Jin Hyeok; Ryu, Hwaseong; Kim, Yong-Woo; Jeon, Ung Bae; Nam, Kyung Jin [Pusan National University Yangsan Hospital, Department of Radiology, Yangsan-si, Gyeongsangnam-do (Korea, Republic of); Han, Junhee [Pusan National University Yangsan Hospital, Division of Biostatistics, Research Institute for Convergence of Biomedical Science and Technology, Yangsan-si, Gyeongsangnam-do (Korea, Republic of)

    2017-05-15

    Several recent studies showed the optimal contrast enhancement with a low-concentration and iso-osmolar contrast media in both adult and pediatric patients. However, low contrast media concentrations are not routinely used due to concerns of suboptimal enhancement of cardiac structures and small vessels. To evaluate the feasibility of using iso-osmolar contrast media containing a low iodine dose for CT cardiac angiography at 80 kilovolts (kVp) in neonates and infants. The iodixanol 270 group consisted of 79 CT scans and the iopromide 370 group of 62 CT scans in patients ≤1 year old. Objective measurement of the contrast enhancement was analyzed and contrast-to-noise ratios of the ascending aorta and left ventricle were calculated. Regarding subjective measurement, a four-point scale system was devised to evaluate degrees of contrast enhancement, image noise, motion artifact and overall image quality of each image set. Reader performance for correctly differentiating iodixanol 270 and iopromide 370 by visual assessment was evaluated. Group objective and subjective measurements were nonsignificantly different. Overall sensitivity, specificity and diagnostic accuracy for correctly differentiating iodixanol 270 and iopromide 370 by visual assessment were 42.8%, 59%, and 50%, respectively. The application of iodixanol 270 achieved optimal enhancement for performing pediatric cardiac CT angiography at 80 kVp in neonates and infants. Objective measurements of contrast enhancement and subjective image quality assessments were not statistically different in the iodixanol 270 and iopromide 370 groups. (orig.)

  3. APPLICATION OF SENSOR FUSION TO IMPROVE UAV IMAGE CLASSIFICATION

    Directory of Open Access Journals (Sweden)

    S. Jabari

    2017-08-01

    Full Text Available Image classification is one of the most important tasks of remote sensing projects including the ones that are based on using UAV images. Improving the quality of UAV images directly affects the classification results and can save a huge amount of time and effort in this area. In this study, we show that sensor fusion can improve image quality which results in increasing the accuracy of image classification. Here, we tested two sensor fusion configurations by using a Panchromatic (Pan camera along with either a colour camera or a four-band multi-spectral (MS camera. We use the Pan camera to benefit from its higher sensitivity and the colour or MS camera to benefit from its spectral properties. The resulting images are then compared to the ones acquired by a high resolution single Bayer-pattern colour camera (here referred to as HRC. We assessed the quality of the output images by performing image classification tests. The outputs prove that the proposed sensor fusion configurations can achieve higher accuracies compared to the images of the single Bayer-pattern colour camera. Therefore, incorporating a Pan camera on-board in the UAV missions and performing image fusion can help achieving higher quality images and accordingly higher accuracy classification results.

  4. Application of Sensor Fusion to Improve Uav Image Classification

    Science.gov (United States)

    Jabari, S.; Fathollahi, F.; Zhang, Y.

    2017-08-01

    Image classification is one of the most important tasks of remote sensing projects including the ones that are based on using UAV images. Improving the quality of UAV images directly affects the classification results and can save a huge amount of time and effort in this area. In this study, we show that sensor fusion can improve image quality which results in increasing the accuracy of image classification. Here, we tested two sensor fusion configurations by using a Panchromatic (Pan) camera along with either a colour camera or a four-band multi-spectral (MS) camera. We use the Pan camera to benefit from its higher sensitivity and the colour or MS camera to benefit from its spectral properties. The resulting images are then compared to the ones acquired by a high resolution single Bayer-pattern colour camera (here referred to as HRC). We assessed the quality of the output images by performing image classification tests. The outputs prove that the proposed sensor fusion configurations can achieve higher accuracies compared to the images of the single Bayer-pattern colour camera. Therefore, incorporating a Pan camera on-board in the UAV missions and performing image fusion can help achieving higher quality images and accordingly higher accuracy classification results.

  5. Radiation Dose and Image Quality from Coronary Angiography in 320-Detecor Row CT

    International Nuclear Information System (INIS)

    Thanomphudsa, J.; Krisanachinda, A.; Tumkosit, M.

    2012-01-01

    Introduction: Coronary Computed Tomography Angiography examinations are increasing rapidly. New Computed Tomography has been developed to improve image quality with the patient dose reduction. The purpose of this study is to evaluate radiation dose and image quality of Coronary Computed Tomography Angiography in patients using 320-detector row CT. Methods: Forty-one patients referred for cardiac CT examinations at King Chulalongkorn Memorial Hospital were included in this study. All coronary computed tomographic angiography (CCTA) examinations were performed on the 320-detector row CT, Toshiba Aquilion One. Scanning protocol was investigated on dose estimates and image quality. Patients were scanned base on heart rate (HR) by HR 75 bpm use retrospective with dose modulation. Scanning parameters, kVp, mAs, HR, BMI, CTDIvol(mGy) and DLP(mGy.cm), were recorded to study the factors affecting the image quality and patient dose. And mA and kVp setting depend on BMI of the patient. Effective dose is calculated from DLP using specific conversion factor. The image quality was evaluated in 4 vessels by two radiologists. Noise assessment was also studied quantitatively. Results: The patient effective dose in prospective gating 70-80% was 3.6 ± 0.9 mSv, prospective gating 30-80% (1R-R) was 6.3 ± 1.9 mSv, and 30-80% (2R-R) was 10.8 ± 1.8 mSv and in retrospective with tube current modulation was 12.1± 7.7 mSv. Image noise was highest in PGT 70-80% 1R-R and decreased in RGT with tube current modulation, PGT 30-80% 1R-R and lowest in PGT 30-80% 2 R-R. And overall qualitative image quality was mostly good to excellent score. Discussion: The heart rate, heart rate variability and disease of the patient are affecting in the radiation dose and image quality so the suitable acquisition protocol used could be necessary. the effective dose and the image noise for the image quality. (author)

  6. MR-angiography

    International Nuclear Information System (INIS)

    Seiderer, M.

    1989-01-01

    Three categories of MRI techniques for vascular imaging are discussed: 2d-angiography using rephasing and dephasing pulse sequences and slice selective imaging; 3d-angiography using rehpasing and dephasing pulse sequences and fas 3d-imaging techniques; 3d-angiography using signal intensity modulation caused by pre- and post-contrast data acquisition (e.g. Gadolinium-DTPA) in combination with fast 3d-imaging (only one type of pulse sequence). (H.W.). 6 figs

  7. Combined anatomical and functional imaging using coronary CT angiography and myocardial perfusion SPECT in symptomatic adults with abnormal origin of a coronary artery.

    Science.gov (United States)

    Uebleis, C; Groebner, M; von Ziegler, F; Becker, A; Rischpler, C; Tegtmeyer, R; Becker, C; Lehner, S; Haug, A R; Cumming, P; Bartenstein, P; Franz, W M; Hacker, M

    2012-10-01

    There has been a lack of standardized workup guidelines for patients with congenital abnormal origin of a coronary artery from the opposite sinus (ACAOS). We aimed to evaluate the use of cardiac hybrid imaging using multi-detector row CT (MDCT) for coronary CT angiography (Coronary CTA) and stress-rest myocardial perfusion SPECT (MPS) for comprehensive diagnosis of symptomatic adult patients with ACAOS. Seventeen symptomatic patients (12 men; 54 ± 13 years) presenting with ACAOS underwent coronary CTA and MPS. Imaging data were analyzed by conventional means, and with additional use of 3D image fusion to allocate stress induced perfusion defects (PD) to their supplying coronary arteries. An anomalous RCA arose from the left anterior sinus in eight patients, an abnormal origin from the right sinus was detected in nine patients (5 left coronary arteries, LCA and 4 LCx). Five of the 17 patients (29%) demonstrated a reversible PD in MPS. There was no correlation between the anatomical variants of ACAOS and the presence of myocardial ischemia. Image fusion enabled the allocation of reversible PD to the anomalous vessel in three patients (two cases in the RCA and the other in the LCA territory); PD in two patients were allocated to the territory of artery giving rise to the anomalies, rather than the anomalies themselves. In a small cohort of adult symptomatic patients with ACAOS anomaly there was no relation found between the specific anatomical variant and the appearance of stress induced myocardial ischemia using cardiac hybrid imaging.

  8. Advanced virtual monoenergetic images: improving the contrast of dual-energy CT pulmonary angiography

    International Nuclear Information System (INIS)

    Meier, A.; Wurnig, M.; Desbiolles, L.; Leschka, S.; Frauenfelder, T.; Alkadhi, H.

    2015-01-01

    Aim: To investigate the value of advanced virtual monoenergetic image reconstruction (mono-plus) from dual-energy computed tomography (CT) for improving the contrast of CT pulmonary angiography (CTPA). Materials and methods: Forty consecutive patients (25 women, mean 62.5 years, range 28–87 years) underwent 192-section dual-source CTPA with dual-energy CT (90/150 SnkVp) after the administration of 60 ml contrast media (300 mg iodine/ml). Conventional virtual monochromatic images at 60 keV and 17 mono-plus image datasets from 40–190 keV (in 10 keV steps) were reconstructed. Subjective image quality (artefacts, subjective noise) was rated. Attenuation was measured in the pulmonary trunk and in the right lower lobe pulmonary artery; noise was measured in the periscapular musculature. The signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were calculated for each patient and dataset. Comparisons between monochromatic images and mono-plus images were performed by repeated measures analysis of variance (ANOVA) with post-hoc Bonferroni correction. Results: Interreader agreement was good to excellent for subjective image quality (ICC: 0.616–0.889). As compared to conventional 60 keV images, artefacts occurred less (p=0.001) and subjective noise was rated lower (p<0.001) in mono-plus 40 keV images. Noise was lower (p<0.001), and the SNR and CNR in the pulmonary trunk and right lower lobe pulmonary artery were higher (both, p<0.001) in mono-plus 40 keV images compared to conventional monoenergetic 60 keV images. Transient interruption of contrast (TIC) was found in 14/40 (35%) of patients, with subjective contrast being similar 8/40 (20%) or higher 32/40 (80%) in mono-plus 40 keV as compared to conventional monoenergetic 60 keV images. Conclusions: Compared to conventional virtual monoenergetic imaging, mono-plus images at 40 keV improve the contrast of dual-energy CTPA. - Highlights: • Advanced monoenergetic image reconstruction from dual-energy CT

  9. Pocket book on setting techniques for medical imaging. X-ray diagnostics, angiography, CT, MRT. 4. rev. and enl. ed.; Taschenatlas Einstelltechnik. Roentgendiagnostik, Angiografie, CT, MRT

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, Torsten B.; Reif, Emil [Caritas-Krankenhaus, Dillingen/Saar (Germany)

    2009-07-01

    The pocketbook on setting techniques for medical imaging is concerned with the problem to prepare appropriate images for diagnostic purposes using modern high-technology instruments like x-ray diagnostics, angiography, computerized tomography and magnetic resonance tomography. The following issues are covered: Head, spinal column, upper extremities, lower extremities, thorax, gastrointestinal tract, intravenous organ examination, angiography, computerized tomography, NMR imaging.

  10. Diagnostic accuracy of contrast-enhanced MR angiography and unenhanced proton MR imaging compared with CT pulmonary angiography in chronic thromboembolic pulmonary hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Rajaram, Smitha [Unit of Academic Radiology, University of Sheffield, Sheffield (United Kingdom); Academic Unit of Radiology, C Floor, Royal Hallamshire Hospital, Sheffield (United Kingdom); Swift, Andrew J.; Wild, Jim M. [Unit of Academic Radiology, University of Sheffield, Sheffield (United Kingdom); Sheffield Cardiovascular Biomedical Research Unit, Sheffield (United Kingdom); Capener, David; Telfer, Adam [Unit of Academic Radiology, University of Sheffield, Sheffield (United Kingdom); Davies, Christine; Hill, Catherine [Sheffield Teaching Hospitals Trust, Department of Radiology, Sheffield (United Kingdom); Condliffe, Robin; Elliot, Charles; Kiely, David G. [Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield (United Kingdom); Sheffield Cardiovascular Biomedical Research Unit, Sheffield (United Kingdom); Hurdman, Judith [Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield (United Kingdom)

    2012-02-15

    To evaluate the diagnostic accuracy of contrast-enhanced MR angiography (CE-MRA) and the added benefit of unenhanced proton MR angiography compared with CT pulmonary angiography (CTPA) in patients with chronic thromboembolic disease (CTE). A 2 year retrospective study of 53 patients with chronic thromboembolic pulmonary hypertension who underwent CTPA and MRI for suspected pulmonary hypertension and a control group of 36 patients with no CT evidence of pulmonary embolism. The MRI was evaluated for CTE and the combined diagnostic accuracy of ce-MRA and unenhanced proton MRA was determined. CE-MRA generated lung perfusion maps were also assessed. The overall sensitivity and specificity of CE-MRA in diagnosing proximal and distal CTE were 98% and 94%, respectively. The sensitivity improved from 50% to 88% for central vessel disease when CE-MRA images were analysed with unenhanced proton MRA. The CE-MRA identified more stenoses (29/18), post-stenosis dilatation (23/7) and occlusions (37/29) compared with CTPA. The CE-MRA perfusion images showed a sensitivity of 92% for diagnosing CTE. CE-MRA has high sensitivity and specificity for diagnosing CTE. The sensitivity of CE-MRA for visualisation of adherent central and lobar thrombus significantly improves with the addition of unenhanced proton MRA which delineates the vessel wall. (orig.)

  11. Diagnostic accuracy of contrast-enhanced MR angiography and unenhanced proton MR imaging compared with CT pulmonary angiography in chronic thromboembolic pulmonary hypertension

    International Nuclear Information System (INIS)

    Rajaram, Smitha; Swift, Andrew J.; Wild, Jim M.; Capener, David; Telfer, Adam; Davies, Christine; Hill, Catherine; Condliffe, Robin; Elliot, Charles; Kiely, David G.; Hurdman, Judith

    2012-01-01

    To evaluate the diagnostic accuracy of contrast-enhanced MR angiography (CE-MRA) and the added benefit of unenhanced proton MR angiography compared with CT pulmonary angiography (CTPA) in patients with chronic thromboembolic disease (CTE). A 2 year retrospective study of 53 patients with chronic thromboembolic pulmonary hypertension who underwent CTPA and MRI for suspected pulmonary hypertension and a control group of 36 patients with no CT evidence of pulmonary embolism. The MRI was evaluated for CTE and the combined diagnostic accuracy of ce-MRA and unenhanced proton MRA was determined. CE-MRA generated lung perfusion maps were also assessed. The overall sensitivity and specificity of CE-MRA in diagnosing proximal and distal CTE were 98% and 94%, respectively. The sensitivity improved from 50% to 88% for central vessel disease when CE-MRA images were analysed with unenhanced proton MRA. The CE-MRA identified more stenoses (29/18), post-stenosis dilatation (23/7) and occlusions (37/29) compared with CTPA. The CE-MRA perfusion images showed a sensitivity of 92% for diagnosing CTE. CE-MRA has high sensitivity and specificity for diagnosing CTE. The sensitivity of CE-MRA for visualisation of adherent central and lobar thrombus significantly improves with the addition of unenhanced proton MRA which delineates the vessel wall. (orig.)

  12. Magnetic resonance imaging and angiography of the brain in embolic left atrial myxoma

    International Nuclear Information System (INIS)

    Marazuela, M.; Yebra, M.; Diego, J.; Durantez, A.; Garcia-Merino, A.; Brasa, J.M.

    1989-01-01

    A case of left atrial myxoma presenting exclusively with neurological symptoms, studies with magnetic resonance imaging (MRI) combined with cerebral angiography and computed tomography (CT) is reported. Typical angiographic findings suggested the diagnosis of myxoma. MRI showed multiple ischemic lesions disseminated throughout the entire brain, some of which had been clinically asymptomatic. Because of its sensitivity in identifying small cerebral infarcts, MRI should prove in the future to be a first-choice technique in the evaluation of the presence of an extent of cerebral involvement in embolic left atrial myxoma. (orig.)

  13. The role of angiography in the congruence of cardiovascular measurements between autopsy and postmortem imaging.

    Science.gov (United States)

    Troxler, Renaud; Minoiu, Costin; Vaucher, Paul; Michaud, Katarzyna; Doenz, Francesco; Ducrot, Kewin; Grabherr, Silke

    2018-01-01

    Postmortem CT angiography is the method of choice for the postmortem imaging investigations of the cardiovascular (CV) system. However, autopsy still remains the gold standard for CV measurement. Nevertheless, there are not any studies on CV measurements on the multi-phase postmortem angiography (MPMCTA) which includes comparisons with autopsy. Therefore, the aim of this study is to compare CV measurements between the native CT scan and the three phases of the MPMCTA to find out which of these modalities correlate the best with autopsy measurements. For this study, we selected retrospectively 50 postmortem cases that underwent both MPMCTA and autopsy. A comparison was carried out between the CV measurements obtained with imaging (aorta; heart cavities and cardiac wall thicknesses; maximum cardiac diameter and cardiothoracic ratio) and at the autopsy (aorta; cardiac valves, ventricular thicknesses, and weight). Our results show that the dynamic phase displays an advantage for the measurement of the aortas. However, the MPMCTA is not accurate to measure the cardiac wall thicknesses. The measurements of the heart cavities show no correlation with the heart valves. The cardiothoracic ratio measured by the MPMCTA shows no correlation with the heart weight. Nevertheless, the maximum cardiac diameter exhibits a correlation with the latter on the venous and dynamic phase. These results show that only few CV parameters measured with imaging correlate with measurement obtained at the autopsy. These results indicate that in order to better estimate values obtained at the autopsy, we need to define new reference values for the CV measurement on MPMCTA.

  14. The use of routine imaging data in diagnosis of cerebral pseudoaneurysm prior to angiography

    International Nuclear Information System (INIS)

    Brzozowski, Krzysztof; Frankowska, Emilia; Piasecki, Piotr; Zięcina, Piotr; Żukowski, Paweł; Bogusławska-Walecka, Romana

    2011-01-01

    Purpose: A false aneurysm is rare and underdiagnosed complication of intracranial hemorrhage. Objective of the study was to point out diagnostic imaging signs of false aneurysm and to determine frequency and diagnostic significance of these signs. Materials and methods: Cerebral arteriography performed in our center from November 2007 to September 2010 revealed the false aneurysm in 8 patients (4 male, 4 female, mean age was 38 years). During the same angiographic procedure 6 patients were treated by endovascular embolization using coils, mixture of Histoacryl and Lipiodol or Onyx (liquid embolic material). Authors retrospectively analyzed preprocedural studies (computed tomography, magnetic resonance imaging) and angiographic findings to identify signs specific to false aneurysm. Results: Computed tomographic findings that are not specific but should raise suspicion of the false aneurysm include: enlargement of parenchymal hematoma dimensions, unusual or delayed evolution of hematoma and spot sign associated with acute hematoma expansion. More specific signs can be revealed in digital subtraction angiography that shows a globular shaped neckless aneurysmal sac, delayed filling and emptying of contrast agent and stagnation of contrast with regard to the head position. Conclusion: Although preangiographic imaging studies findings in patients with false aneurysms are not specific, they should lead to angiographic validation, especially enlarging parenchymal hematoma and atypical hematoma evolution. Digital subtraction angiography makes it possible to diagnose the lesion and to use endovascular embolization techniques, which are currently the method of choice for treatment of pseudoaneurysms.

  15. Micro-angiography for neuro-vascular imaging. I. Experimental evaluation and feasibility

    International Nuclear Information System (INIS)

    Ganguly, Arundhuti; Rudin, Stephen; Bednarek, Daniel R.; Hoffmann, Kenneth R.; Kyprianou, Iacovos S.

    2003-01-01

    Minimally invasive image-guided neuro-vascular interventions require very high image-resolution and quality, specifically over regions-of-interest (ROI) crucial to the procedure. ROI imaging or micro-angiography, allows limited patient integral radiation dose while permitting rapid frame transfer of high-resolution images. The design and performance of a charge coupled device (CCD) based x-ray detector or micro-angiographic camera was assessed for neuro-vascular procedures. The detector consists of a 250-μm-thick CsI(Tl) phosphor fiber-optically coupled through a 1.8:1 taper to a CCD chip, with an effective image pixel size of 50 μm and a frame rate of 5 fps in the 2:1 pixel-binned mode. The characteristics of the camera including the modulation transfer function (MTF), the noise equivalent quanta, the detective quantum efficiency, observer studies, and the effect of geometric magnification were evaluated. The MTF was found to have nonzero (1.7%) value at the Nyquist frequency of 10 cycles/mm, while the DQE(0) had a value of ∼55%. All values were measured using head equivalent attenuating material in the beam at 80 kVp. Human observer studies performed using the 2 Alternative Forced Choice method revealed that iodinated vessels with inner diameter of 100 μm and 2 cm in length can be seen with a confidence level greater than 75%. The observer studies included a comparison with ideal observer performance calculations based on the integral signal to noise ratio in the image. Probabilities of visualization of various objects of interest in a neuro-intervention, such as stents, were assessed. A geometric magnification of 1 was found to be best for imaging under neuro-angiographic conditions. The detector appeared to satisfy all the demands of neuro-angiography and showed promise as an improvement over existing angiographic detectors

  16. Distributed MIMO-ISAR Sub-image Fusion Method

    Directory of Open Access Journals (Sweden)

    Gu Wenkun

    2017-02-01

    Full Text Available The fast fluctuation associated with maneuvering a target’s radar cross-section often affects the imaging performance stability of traditional monostatic Inverse Synthetic Aperture Radar (ISAR. To address this problem, in this study, we propose an imaging method based on the fusion of sub-images of frequencydiversity-distributed multiple Input-Multiple Output-Inverse Synthetic Aperture Radar (MIMO-ISAR. First, we establish the analytic expression of a two-dimensional ISAR sub-image acquired by different channels of distributed MIMO-ISAR. Then, we derive the distance and azimuth distortion factors of the image acquired by the different channels. By compensating for the distortion of the ISAR image, we ultimately realize distributed MIMO-ISAR fusion imaging. Simulations verify the validity of this imaging method using distributed MIMO-ISAR.

  17. FUSION SEGMENTATION METHOD BASED ON FUZZY THEORY FOR COLOR IMAGES

    Directory of Open Access Journals (Sweden)

    J. Zhao

    2017-09-01

    Full Text Available The image segmentation method based on two-dimensional histogram segments the image according to the thresholds of the intensity of the target pixel and the average intensity of its neighborhood. This method is essentially a hard-decision method. Due to the uncertainties when labeling the pixels around the threshold, the hard-decision method can easily get the wrong segmentation result. Therefore, a fusion segmentation method based on fuzzy theory is proposed in this paper. We use membership function to model the uncertainties on each color channel of the color image. Then, we segment the color image according to the fuzzy reasoning. The experiment results show that our proposed method can get better segmentation results both on the natural scene images and optical remote sensing images compared with the traditional thresholding method. The fusion method in this paper can provide new ideas for the information extraction of optical remote sensing images and polarization SAR images.

  18. Preliminary study of lateral cerebral angiography with reverse rotation in the digital image registration and subtraction

    International Nuclear Information System (INIS)

    Shen Zhenglin; Liu Dongyang; Shen Zhenghai; Li Shuping; Zhang Ziyan; Wu Yongjuan; Liu Peijun

    2012-01-01

    Objective: Investigate the value and feasibility of image registration with reverse rotation in lateral cerebral DSA. Methods: (1) Experimental study: the target images were subtracted directly, and subtracted again after reverse rotation. Software of registration and subtraction with reverse rotation edited by the author utilizing Visual Basic. The function of the automatic angle detection by the software were evaluated to see whether it detected the angle of line. The subtraction function of DSA by the software was evaluated. (2) Clinical retrospective study: the untreated mask and target images of 15 patients with motion along vertical axis during lateral cerebral DSA were uploaded to the software. The target images were processed with and without the software to get two sets of images. (3) Evaluation: four experienced radiologists read and compared the two sets of the images,and graded their findings. Results: (1) The automatic detection by the software suggested that the target images should be rotated counterclockwise 1.3°. The subtraction result of the software was satisfactory. (2) In the 15 sets of images, there were only three sets of images deemed optimal after traditional subtraction. After reverse rotation, artifacts were significantly reduced and the image sharper. There were ten cases with significant artifacts after traditional subtraction, and those images were sharper and showed more peripheral vessels after reverse rotation. The traditional subtraction images of two sets could not be interpreted,the reverse rotation registration images reached the diagnostic quality. (3) Subjective evaluation: there were more information and less noise and distortion in the registration images with reverse rotation than in the traditional subtraction. But the image resolution decreased slightly after reverse rotation registration. Conclusion: The registration of digital angiography with reverse rotation can improve the image quality in lateral cerebral DSA

  19. Evaluation of various image reconstruction parameters in lower extremity stents using multidetector-row CT angiography: initial findings

    International Nuclear Information System (INIS)

    Heuschmid, Martin; Wiesinger, Benjamin; Tepe, Gunnar; Luz, Oliver; Kopp, Andreas F.; Claussen, Claus D.; Duda, Stephan H.

    2007-01-01

    Image quality, visible lumen and patency of lower limb stents was assessed by multidetector-row computed tomography (MDCT) angiography using various reconstruction parameters and the results compared with conventional angiography. Fourteen patients (25 stents) were evaluated. From MDCT datasets, axial and coronal oblique reformations were reconstructed using differing reconstruction parameters (slice thickness, kernel, views). Artifacts and image quality were assessed using a five-degree scale (1=excellent, 5=poor). Visible stent diameter was measured. Stenosis severity was compared with calibrated catheter angiography. The image quality of medium and sharp image kernels were good/fair (1.9-2.4), while smooth kernel provided only acceptable/poor image quality (3.9-4.4). Coronal oblique images were rated superior to assess in-stent lumen rather than axial. Using medium and sharp kernels, the visible stent lumen was significantly greater than using smooth kernel (P<0.001). thirteen out of fourteen patients (24/25 stents) were correctly classified as patent. In one patient, in-stent stenosis (≥50%) was falsely diagnosed using CT angiography (CTA) with smooth kernel and was, therefore, rated as false positive. Coronal oblique views, as well as medium and sharp kernels, have shown the best results regarding image quality to assess stent patency in the lower limb. Therefore, MDCT could be a valuable non-invasive modality for stent imaging in the peripheral vasculature. (orig.)

  20. Imaging fusion (SPECT/CT) in degenerative disease of spine

    International Nuclear Information System (INIS)

    Bernal, P.; Ucros, G.; Bermudez, S.; Ocampo, M.

    2007-01-01

    Full text: Objective: To determine the utility of Fusion Imaging SPECT/CT in degenerative pathology of the spine and to establish the impact of the use of fusion imaging in spinal pain due to degenerative changes of the spine. Materials and methods: 44 Patients (M=21, F=23) average age of 63 years and with degenerative pathology of spine were sent to Diagnosis Imaging department in FSFB. Bone scintigraphy (SPECT), CT of spine (cervical: 30%, Lumbar 70%) and fusion imaging were performed in all of them. Bone scintigraphy was carried out in a gamma camera Siemens Diacam double head attached to ESOFT computer. The images were acquired in matrix 128 x 128, 20 seg/imag, 64 images. CT of spine was performed same day or two days after in Helycoidal Siemens somatom emotion CT. The fusion was done in a Dicom workstation in sagital, axial and coronal reconstruction. The findings were evaluated by 2 Nuclear Medicine physicians and 2 radiologists of the staff of FSFB in an independent way. Results: Bone scan (SPECT) and CT of 44 patients were evaluated. CT showed facet joint osteoarthrities in 27 (61.3%) patients, uncovertebral joint arthrosis in 7 (15.9%), bulging disc in 9(20.4%), spinal nucleus lesion in 7(15.9%), osteophytes in 9 (20.4%), spinal foraminal stenosis in 7 (15.9%), spondylolysis/spondylolisthesis in 4 (9%). Bone scan showed facet joint osteoarthrities in 29 (65.9%), uncovertebral joint arthrosis in 4 (9%), osteophytes in 9 (20.4%) and normal 3 (6.8%). The imaging fusion showed coincidence findings (main lesion in CT with high uptake in scintigraphy) in 34 patients (77.2%) and no coincidence in 10 (22.8%). In 15 (34.09%) patients the fusion provided additional information. The analysis of the findings of CT and SPECT showed similar results in most of the cases and the fusion didn't provide additional information but it allowed to confirm the findings but when the findings didn't match where the CT showed several findings and SPECT only one area with high uptake

  1. Parenchymal abnormalities in cerebral venous thrombosis: findings of magnetic resonance imaging and magnetic resonance angiography

    International Nuclear Information System (INIS)

    Ferreira, Clecia Santos; Pellini, Marcos; Boasquevisque, Edson; Souza, Luis Alberto M. de

    2006-01-01

    Objective: to determine the frequency and localization of parenchymal abnormalities in cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography as well as their correlation with the territory and affected venous drainage. Materials and methods: retrospective analysis (1996 to 2004) of 21 patients (3 male and 18 female) age range between 3 and 82 years (mean 40 years, median 36 years) with clinical and radiological diagnosis of cerebral venous thrombosis on magnetic resonance imaging and magnetic resonance angiography in 2D PC, 3D PC and contrast-enhanced 3D TOF sequences. The statistical analysis was performed with the qui-square test. Four patients had follow-up exams and three patients underwent digital subtraction angiography. Results: main predisposing factors were: infection, use of oral contraceptives, hormone replacement therapy and collagenosis. Predominant symptoms included: focal deficit, headache, alteration of consciousness level and seizures. Most frequent parenchymal manifestations were: cortical/subcortical edema or infarct, venous congestion and collateral circulation, meningeal enhancement and thalamic and basal ganglia edema or infarct. Occlusion occurred mainly in superior sagittal, left transverse, left sigmoid and straight sinuses. Cavernous sinus and cortical veins thrombosis are uncommon events. Conclusion: cerebral venous thrombosis is an uncommon cause of stroke, with favorable prognosis because of its reversibility. Diagnosis is highly dependent on the radiologist capacity to recognize the presentations of this disease, principally in cases where the diagnosis is suggested by parenchymal abnormalities rather than necessarily by visualization of the thrombus itself. An accurate and rapid diagnosis allows an immediate treatment, reducing the morbidity and mortality rates. (author)

  2. The reduction of motion artifacts in digital subtraction angiography by geometrical image transformation

    International Nuclear Information System (INIS)

    Fitzpatrick, J.M.; Pickens, D.R.; Mandava, V.R.; Grefenstette, J.J.

    1988-01-01

    In the diagnosis of arteriosclerosis, radio-opaque dye is injected into the interior of the arteries to make them visible. Because of its increased contrast sensitivity, digital subtraction angiography has the potential for providing diagnostic images of arteries with reduced dye volumes. In the conventional technique, a mask image, acquired before the introduction of the dye, is subtracted from the contrast image, acquired after the dye is introduced, to produce a difference image in which only the dye in the arteries is visible. The usefulness of this technique has been severely limited by the image degradation caused by patient motion during image acquisition. This motion produces artifacts in the difference image that obscure the arteries. One technique for dealing with the problem is to reduce the degradation by means of image registration. The registration is carried out by means of a geometrical transformation of the mask image before subtraction so that it is in registration with the contrast image. This paper describes a technique for determining an optimal transformation. The authors employ a one-to-one elastic mapping and the Jacobian of that mapping to produce a geometrical image transformation. They choose a parameterized class of such mappings and use a heuristic search algorithm to optimize the parameters to minimize the severity of the motion artifacts. To increase the speed of the optimization process they use a statistical image comparison technique that provides a quick approximate evaluation of each image transformation. They present the experimental results of the application of their registration system to mask-contrast pairs, for images acquired from a specially designed phantom, and for clinical images

  3. Multi-slice spiral CT coronary angiography: influence of heart rate and reconstruction window on image quality

    International Nuclear Information System (INIS)

    Mao Dingbiao; Hua Yanqing; Wang Mingpeng; Zhang Guozhen; Wu Weilan; Hu Fei; Ge Xiaojun; Ding Qiyong

    2004-01-01

    Objective: To evaluate the influence of heart rate and reconstruction window on image quality of multi-slice spiral CT coronary angiography. Methods: Retrospectively ECG-gated MSCT coronary angiography were performed in 80 healthy cases. Results: Four coronary (RCA, LM, LAD, LCX) segments were analyzed in each patient with regard to image quality. 82.1% (46/56) of the coronary segments were sufficient for analysis in patients with heart rate ≤60 bpm, 63.4% (104/164) with 61-70 bpm, 41.2%(28/68) with 71-80 bpm, and 31.2%(10/32) with>80 bpm, respectively. The left anterior descending artery, left circumflex artery, and the right coronary artery were best visualized when the reconstruction window was 60%-70%, 50%-60%, and 50%-70%, respectively. Conclusion: Image quality of MSCT coronary angiography is highly dependent on heart rate and reconstruction window

  4. X-ray imaging in the laser-fusion program

    International Nuclear Information System (INIS)

    McCall, G.H.

    1977-01-01

    Imaging devices which are used or planned for x-ray imaging in the laser-fusion program are discussed. Resolution criteria are explained, and a suggestion is made for using the modulation transfer function as a uniform definition of resolution for these devices

  5. Three-dimensional imaging of lumbar spinal fusions

    International Nuclear Information System (INIS)

    Chafetz, N.; Hunter, J.C.; Cann, C.E.; Morris, J.M.; Ax, L.; Catterling, K.F.

    1986-01-01

    Using a Cemax 1000 three-dimensional (3D) imaging computer/workstation, the author evaluated 15 patients with lumbar spinal fusions (four with pseudarthrosis). Both axial images with sagittal and coronal reformations and 3D images were obtained. The diagnoses (spinal stenosis and psuedarthrosis) were changed in four patients, confirmed in six patients, and unchanged in five patients with the addition of the 3D images. The ''cut-away'' 3D images proved particularly helpful for evaluation of central and lateral spinal stenosis, whereas the ''external'' 3D images were most useful for evaluation of the integrity of the fusion. Additionally, orthopedic surgeons found 3D images superior for both surgical planning and explaining pathology to patients

  6. A comparative analysis of pulmonary ventilation-perfusion imaging with pulmonary angiography in the diagnosis of pulmonary embolism

    International Nuclear Information System (INIS)

    Wang Jincheng; Mi Hongzhi; Wang Qian; Zhang Weijun; Lu Biao; Yang Hao; Ding Jian; Lu Yao

    2001-01-01

    Objective: To assess the value of ventilation-perfusion imaging in the diagnosis of pulmonary embolism (PE). Methods: Thirty consecutive patients with clinically suspected pulmonary embolism were studied, male: female 15:15, mean age was (36.2 +- 13.9) years. The chest radiograms were obtained in all 30 patients. All patients underwent radionuclide ventilation-perfusion imaging and pulmonary angiography. Results: Of the 30 patients, 22 with lobe, multiple segment or multi-subsegment perfusion defects and normal or nearly normal ventilation images were reported as PE. 20 of them were confirmed to be with PE by pulmonary angiography, 2 patients were not confirmed. Eight of 30 patients with multiple perfusion defects, ventilative abnormalities were reported as non-PE and the diagnoses were confirmed by pulmonary angiography. The sensitivity, specificity and accuracy of diagnosis of PE by ventilation-perfusion imaging was 100%, 80.0% and 93.3% respectively. Conclusions: (1) Ventilation-perfusion imaging is one of the most valuable methods in the diagnosis of PE. (2) The results suggest that pulmonary embolism can be diagnosed non-invasively in most patients on the basis of clinical manifestation, chest radiograms and ventilation-perfusion imaging findings. (3) Pulmonary angiography is required while clinical manifestation and ventilation-perfusion imaging findings are discordant with each other

  7. Visible and NIR image fusion using weight-map-guided Laplacian ...

    Indian Academy of Sciences (India)

    Ashish V Vanmali

    fusion perspective, instead of the conventional haze imaging model. The proposed ... Image dehazing; Laplacian–Gaussian pyramid; multi-resolution fusion; visible–NIR image fusion; weight map. 1. .... Tan's [8] work is based on two assumptions: first, images ... responding colour image, since NIR can penetrate through.

  8. A LabVIEW Platform for Preclinical Imaging Using Digital Subtraction Angiography and Micro-CT.

    Science.gov (United States)

    Badea, Cristian T; Hedlund, Laurence W; Johnson, G Allan

    2013-01-01

    CT and digital subtraction angiography (DSA) are ubiquitous in the clinic. Their preclinical equivalents are valuable imaging methods for studying disease models and treatment. We have developed a dual source/detector X-ray imaging system that we have used for both micro-CT and DSA studies in rodents. The control of such a complex imaging system requires substantial software development for which we use the graphical language LabVIEW (National Instruments, Austin, TX, USA). This paper focuses on a LabVIEW platform that we have developed to enable anatomical and functional imaging with micro-CT and DSA. Our LabVIEW applications integrate and control all the elements of our system including a dual source/detector X-ray system, a mechanical ventilator, a physiological monitor, and a power microinjector for the vascular delivery of X-ray contrast agents. Various applications allow cardiac- and respiratory-gated acquisitions for both DSA and micro-CT studies. Our results illustrate the application of DSA for cardiopulmonary studies and vascular imaging of the liver and coronary arteries. We also show how DSA can be used for functional imaging of the kidney. Finally, the power of 4D micro-CT imaging using both prospective and retrospective gating is shown for cardiac imaging.

  9. Circumferential optical coherence tomography angiography imaging of the swine esophagus using a micromotor balloon catheter.

    Science.gov (United States)

    Lee, Hsiang-Chieh; Ahsen, Osman Oguz; Liang, Kaicheng; Wang, Zhao; Cleveland, Cody; Booth, Lucas; Potsaid, Benjamin; Jayaraman, Vijaysekhar; Cable, Alex E; Mashimo, Hiroshi; Langer, Robert; Traverso, Giovanni; Fujimoto, James G

    2016-08-01

    We demonstrate a micromotor balloon imaging catheter for ultrahigh speed endoscopic optical coherence tomography (OCT) which provides wide area, circumferential structural and angiographic imaging of the esophagus without contrast agents. Using a 1310 nm MEMS tunable wavelength swept VCSEL light source, the system has a 1.2 MHz A-scan rate and ~8.5 µm axial resolution in tissue. The micromotor balloon catheter enables circumferential imaging of the esophagus at 240 frames per second (fps) with a ~30 µm (FWHM) spot size. Volumetric imaging is achieved by proximal pullback of the micromotor assembly within the balloon at 1.5 mm/sec. Volumetric data consisting of 4200 circumferential images of 5,000 A-scans each over a 2.6 cm length, covering a ~13 cm(2) area is acquired in <18 seconds. A non-rigid image registration algorithm is used to suppress motion artifacts from non-uniform rotational distortion (NURD), cardiac motion or respiration. En face OCT images at various depths can be generated. OCT angiography (OCTA) is computed using intensity decorrelation between sequential pairs of circumferential scans and enables three-dimensional visualization of vasculature. Wide area volumetric OCT and OCTA imaging of the swine esophagus in vivo is demonstrated.

  10. Efficacy of 'fine' focal spot imaging in CT abdominal angiography

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Lawrence Chia Wei; Devapalasundaram, Ashwini; Ardley, Nicholas [Monash Health, Department of Diagnostic Imaging, Clayton, Victoria (Australia); Lau, Kenneth K. [Monash Health, Department of Diagnostic Imaging, Clayton, Victoria (Australia); Monash University, Department of Medicine, Faculty of Medicine, Nursing, and Health Sciences, Victoria (Australia); Buchan, Kevin [Phillips Healthcare, Clinical Science, PO Box 312, Mont Albert, Victoria (Australia); Huynh, Minh [RMIT University, School of Mathematical and Geospatial Sciences, Victoria (Australia)

    2014-12-15

    To assess the efficacy of fine focal spot imaging in calcification beam-hardening artefact reduction and vessel clarity on CT abdominal angiography (CTAA). Adult patients of any age and gender who presented for CTAA were included. Thirty-nine patients were examined with a standard focal spot size (SFSS) of 1 x 1 mm in the first 3 months while 31 consecutive patients were examined with a fine focal spot size (FFSS) of 1 x 0.5 mm in the following 3 months. Vessel clarity and calcification beam-hardening artefacts of the abdominal aorta, celiac axis, superior mesenteric artery, inferior mesenteric artery, renal arteries, and iliac arteries were assessed using a 5-point grading scale by two blinded radiologists randomly. Cohen's Kappa test indicated that on average, there was substantial agreement among reviewers for vessel wall clarity and calcification artefact grading. Mann-Whitney test showed that there was a significant difference between the two groups, with FFSS performing significantly better for vessel clarity (U, 6481.50; p < 0.001; r, 0.73) and calcification artefact reduction (U, 1916; p < 0.001; r, 0.77). Fine focus CT angiography produces images with better vessel wall clarity and less vessel calcification beam-hardening artefact. (orig.)

  11. Imaging of peripheral arteries by 16-row multidetector computed tomography angiography: A feasible tool?

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Anuj [Department of Radiology, National Organ Transplant Program, Tripoli (Libyan Arab Jamahiriya)]. E-mail: dranujmish@yahoo.com; Bhaktarahalli, Jahnavi Narayanaswamy [Department of Clinical Pathology, Tripoli Medical Centre, Tripoli (Libyan Arab Jamahiriya); Ehtuish, Ehtuish F. [Department of Surgery, National Organ Transplant Program, Tripoli (Libyan Arab Jamahiriya)

    2007-03-15

    Objective: To evaluate the efficacy of multidetector (16-row) computed tomography (MDCT) in imaging the upper and lower limb arterial tree in trauma and peripheral arterial occlusive disease (PAOD). Methods: Thirty-three patients underwent MDCT angiography (MDCTA) of the upper or the lower limb on 16-row MDCT scanner between November, 2004 and July, 2005. The findings were compared with the surgical outcome in cases with trauma and suspected arterial injuries or color Doppler correlation was obtained for patients of PAOD. Results: MDCTA allowed a comprehensive diagnostic work-up in all trauma cases with suspected arterial injuries. In the 23 cases of PAOD, MDCT adequately demonstrated the presence of stenosis or occlusion, its degree and extent, the presence of collaterals and plaques. Conclusion: Our experience of CT angiography (CTA) with 16-row MDCT scanner has clearly demonstrated its efficacy as a promising, new, fast, accurate, safe and non-invasive imaging modality of choice in cases of trauma with suspected arterial injuries and as a useful screening modality in cases of PAOD for diagnosis and for grading.

  12. Imaging of peripheral arteries by 16-row multidetector computed tomography angiography: A feasible tool?

    International Nuclear Information System (INIS)

    Mishra, Anuj; Bhaktarahalli, Jahnavi Narayanaswamy; Ehtuish, Ehtuish F.

    2007-01-01

    Objective: To evaluate the efficacy of multidetector (16-row) computed tomography (MDCT) in imaging the upper and lower limb arterial tree in trauma and peripheral arterial occlusive disease (PAOD). Methods: Thirty-three patients underwent MDCT angiography (MDCTA) of the upper or the lower limb on 16-row MDCT scanner between November, 2004 and July, 2005. The findings were compared with the surgical outcome in cases with trauma and suspected arterial injuries or color Doppler correlation was obtained for patients of PAOD. Results: MDCTA allowed a comprehensive diagnostic work-up in all trauma cases with suspected arterial injuries. In the 23 cases of PAOD, MDCT adequately demonstrated the presence of stenosis or occlusion, its degree and extent, the presence of collaterals and plaques. Conclusion: Our experience of CT angiography (CTA) with 16-row MDCT scanner has clearly demonstrated its efficacy as a promising, new, fast, accurate, safe and non-invasive imaging modality of choice in cases of trauma with suspected arterial injuries and as a useful screening modality in cases of PAOD for diagnosis and for grading

  13. Quantitative parameters of image quality in 64-slice computed tomography angiography of the coronary arteries

    International Nuclear Information System (INIS)

    Ferencik, Maros; Nomura, Cesar H.; Maurovich-Horvat, Pal; Hoffmann, Udo; Pena, Antonio J.; Cury, Ricardo C.; Abbara, Suhny; Nieman, Koen; Fatima, Umaima; Achenbach, Stephan; Brady, Thomas J.

    2006-01-01

    We explored quantitative parameters of image quality in consecutive patients undergoing 64-slice multi-detector computed tomography (MDCT) coronary angiography for clinical reasons. Forty-two patients (36 men, mean age 61 ± 11 years, mean heart rate 63 ± 10 bpm) underwent contrast-enhanced MDCT coronary angiography with a 64-slice scanner (Siemens Sensation 64, 64 mmx 0.6 mm collimation, 330 ms tube rotation, 850 mAs, 120 kV). Two independent observers measured the overall visualized vessel length and the length of the coronary arteries visualized without motion artifacts in curved multiplanar reformatted images. Contrast-to-noise ratio was measured in the proximal and distal segments of the coronary arteries. The mean length of visualized coronary arteries was: left main 12 ± 6 mm, left anterior descending 149 ± 25 mm, left circumflex 89 ± 30 mm, and right coronary artery 161 ± 38 mm. On average, 97 ± 5% of the total visualized vessel length was depicted without motion artifacts (left main 100 ± 0%, left anterior descending 97 ± 6%, left circumflex 98 ± 5%, and right coronary artery 95 ± 6%). In 27 patients with a heart rate ≤65 bpm, 98 ± 4% of the overall visualized vessel length was imaged without motion artifacts, whereas 96 ± 6% of the overall visualized vessel length was imaged without motion artifacts in 15 patients with a heart rate >65 bpm (p < 0.001). The mean contrast-to-noise ratio in all measured coronary arteries was 14.6 ± 4.7 (proximal coronary segments: range 15.1 ± 4.4 to 16.1 ± 5.0, distal coronary segments: range 11.4 ± 4.2 to 15.9 ± 4.9). In conclusion, 64-slice MDCT permits reliable visualization of the coronary arteries with minimal motion artifacts and high CNR in consecutive patients referred for non-invasive MDCT coronary angiography. Low heart rate is an important prerequisite for excellent image quality

  14. External marker-based fusion of functional and morphological images

    International Nuclear Information System (INIS)

    Kremp, S.; Schaefer, A.; Alexander, C.; Kirsch, C.M.

    1999-01-01

    The fusion of image data resulting from methods oriented toward morphology like CT, MRI with functional information coming from nuclear medicine (SPECT, PET) is frequently applied to allow for a better association between functional findings and anatomical structures. A new software was developed to provide image fusion using PET, SPECT, MRI and CT data within a short processing periode for brain as well as whole body examinations in particular thorax and abdomen. The software utilizes external markers (brain) or anatomical landmarks (thorax) for correlation. The fusion requires a periode of approx. 15 min. The examples shown emphasize the high gain in diagnostic information by fusing image data of anatomical and functional methods. (orig.) [de

  15. Alternate method for to realize image fusion; Metodo alterno para realizar fusion de imagenes

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, L; Hernandez, F; Fernandez, R [Departamento de Medicina Nuclear, Imagenologia Diagnostica. Centro Medico de Xalapa, Veracruz (Mexico)

    2005-07-01

    At the present time the image departments have the necessity of carrying out image fusion obtained of diverse apparatuses. Conventionally its fuse resonance or tomography images by X-rays with functional images as the gammagrams and PET images. The fusion technology is for sale with the modern image equipment and not all the cabinets of nuclear medicine have access to it. By this reason we analyze, study and we find a solution so that all the cabinets of nuclear medicine can benefit of the image fusion. The first indispensable requirement is to have a personal computer with capacity to put up image digitizer cards. It is also possible, if one has a gamma camera that can export images in JPG, GIF, TIFF or BMP formats, to do without of the digitizer card and to record the images in a disk to be able to use them in the personal computer. It is required of one of the following commercially available graph design programs: Corel Draw, Photo Shop, FreeHand, Illustrator or Macromedia Flash that are those that we evaluate and that its allow to make the images fusion. Anyone of them works well and a short training is required to be able to manage them. It is necessary a photographic digital camera with a resolution of at least 3.0 mega pixel. The procedure consists on taking photographic images of the radiological studies that the patient already has, selecting those demonstrative images of the pathology in study and that its can also be concordant with the images that we have created in the gammagraphic studies, whether for planar or tomographic. We transfer the images to the personal computer and we read them with the graph design program. To continuation also reads the gammagraphic images. We use those digital tools to make transparent the images, to clip them, to adjust the sizes and to create the fused images. The process is manual and it is requires of ability and experience to choose the images, the cuts, those sizes and the transparency grade. (Author)

  16. Image fusion and denoising using fractional-order gradient information

    DEFF Research Database (Denmark)

    Mei, Jin-Jin; Dong, Yiqiu; Huang, Ting-Zhu

    Image fusion and denoising are significant in image processing because of the availability of multi-sensor and the presence of the noise. The first-order and second-order gradient information have been effectively applied to deal with fusing the noiseless source images. In this paper, due to the adv...... show that the proposed method outperforms the conventional total variation in methods for simultaneously fusing and denoising....

  17. Quantitative depth resolved microcirculation imaging with optical coherence tomography angiography (Part ΙΙ): Microvascular network imaging.

    Science.gov (United States)

    Gao, Wanrong

    2017-04-17

    In this work, we review the main phenomena that have been explored in OCT angiography to image the vessels of the microcirculation within living tissues with the emphasis on how the different processing algorithms were derived to circumvent specific limitations. Parameters are then discussed that can quantitatively describe the depth-resolved microvascular network for possible clinic diagnosis applications. Finally,future directions in continuing OCT development are discussed. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  18. Assessment of Spatiotemporal Fusion Algorithms for Planet and Worldview Images.

    Science.gov (United States)

    Kwan, Chiman; Zhu, Xiaolin; Gao, Feng; Chou, Bryan; Perez, Daniel; Li, Jiang; Shen, Yuzhong; Koperski, Krzysztof; Marchisio, Giovanni

    2018-03-31

    Although Worldview-2 (WV) images (non-pansharpened) have 2-m resolution, the re-visit times for the same areas may be seven days or more. In contrast, Planet images are collected using small satellites that can cover the whole Earth almost daily. However, the resolution of Planet images is 3.125 m. It would be ideal to fuse these two satellites images to generate high spatial resolution (2 m) and high temporal resolution (1 or 2 days) images for applications such as damage assessment, border monitoring, etc. that require quick decisions. In this paper, we evaluate three approaches to fusing Worldview (WV) and Planet images. These approaches are known as Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM), Flexible Spatiotemporal Data Fusion (FSDAF), and Hybrid Color Mapping (HCM), which have been applied to the fusion of MODIS and Landsat images in recent years. Experimental results using actual Planet and Worldview images demonstrated that the three aforementioned approaches have comparable performance and can all generate high quality prediction images.

  19. Fusion of imaging and nonimaging data for surveillance aircraft

    Science.gov (United States)

    Shahbazian, Elisa; Gagnon, Langis; Duquet, Jean Remi; Macieszczak, Maciej; Valin, Pierre

    1997-06-01

    This paper describes a phased incremental integration approach for application of image analysis and data fusion technologies to provide automated intelligent target tracking and identification for airborne surveillance on board an Aurora Maritime Patrol Aircraft. The sensor suite of the Aurora consists of a radar, an identification friend or foe (IFF) system, an electronic support measures (ESM) system, a spotlight synthetic aperture radar (SSAR), a forward looking infra-red (FLIR) sensor and a link-11 tactical datalink system. Lockheed Martin Canada (LMCan) is developing a testbed, which will be used to analyze and evaluate approaches for combining the data provided by the existing sensors, which were initially not designed to feed a fusion system. Three concurrent research proof-of-concept activities provide techniques, algorithms and methodology into three sequential phases of integration of this testbed. These activities are: (1) analysis of the fusion architecture (track/contact/hybrid) most appropriate for the type of data available, (2) extraction and fusion of simple features from the imaging data into the fusion system performing automatic target identification, and (3) development of a unique software architecture which will permit integration and independent evolution, enhancement and optimization of various decision aid capabilities, such as multi-sensor data fusion (MSDF), situation and threat assessment (STA) and resource management (RM).

  20. Spatial resolution enhancement of satellite image data using fusion approach

    Science.gov (United States)

    Lestiana, H.; Sukristiyanti

    2018-02-01

    Object identification using remote sensing data has a problem when the spatial resolution is not in accordance with the object. The fusion approach is one of methods to solve the problem, to improve the object recognition and to increase the objects information by combining data from multiple sensors. The application of fusion image can be used to estimate the environmental component that is needed to monitor in multiple views, such as evapotranspiration estimation, 3D ground-based characterisation, smart city application, urban environments, terrestrial mapping, and water vegetation. Based on fusion application method, the visible object in land area has been easily recognized using the method. The variety of object information in land area has increased the variation of environmental component estimation. The difficulties in recognizing the invisible object like Submarine Groundwater Discharge (SGD), especially in tropical area, might be decreased by the fusion method. The less variation of the object in the sea surface temperature is a challenge to be solved.

  1. Feature-Fusion Guidelines for Image-Based Multi-Modal Biometric Fusion

    Directory of Open Access Journals (Sweden)

    Dane Brown

    2017-07-01

    Full Text Available The feature level, unlike the match score level, lacks multi-modal fusion guidelines. This work demonstrates a new approach for improved image-based biometric feature-fusion. The approach extracts and combines the face, fingerprint and palmprint at the feature level for improved human identification accuracy. Feature-fusion guidelines, proposed in our recent work, are extended by adding a new face segmentation method and the support vector machine classifier. The new face segmentation method improves the face identification equal error rate (EER by 10%. The support vector machine classifier combined with the new feature selection approach, proposed in our recent work, outperforms other classifiers when using a single training sample. Feature-fusion guidelines take the form of strengths and weaknesses as observed in the applied feature processing modules during preliminary experiments. The guidelines are used to implement an effective biometric fusion system at the feature level, using a novel feature-fusion methodology, reducing the EER of two groups of three datasets namely: SDUMLA face, SDUMLA fingerprint and IITD palmprint; MUCT Face, MCYT Fingerprint and CASIA Palmprint.

  2. Taxonomy of multi-focal nematode image stacks by a CNN based image fusion approach.

    Science.gov (United States)

    Liu, Min; Wang, Xueping; Zhang, Hongzhong

    2018-03-01

    In the biomedical field, digital multi-focal images are very important for documentation and communication of specimen data, because the morphological information for a transparent specimen can be captured in form of a stack of high-quality images. Given biomedical image stacks containing multi-focal images, how to efficiently extract effective features from all layers to classify the image stacks is still an open question. We present to use a deep convolutional neural network (CNN) image fusion based multilinear approach for the taxonomy of multi-focal image stacks. A deep CNN based image fusion technique is used to combine relevant information of multi-focal images within a given image stack into a single image, which is more informative and complete than any single image in the given stack. Besides, multi-focal images within a stack are fused along 3 orthogonal directions, and multiple features extracted from the fused images along different directions are combined by canonical correlation analysis (CCA). Because multi-focal image stacks represent the effect of different factors - texture, shape, different instances within the same class and different classes of objects, we embed the deep CNN based image fusion method within a multilinear framework to propose an image fusion based multilinear classifier. The experimental results on nematode multi-focal image stacks demonstrated that the deep CNN image fusion based multilinear classifier can reach a higher classification rate (95.7%) than that by the previous multilinear based approach (88.7%), even we only use the texture feature instead of the combination of texture and shape features as in the previous work. The proposed deep CNN image fusion based multilinear approach shows great potential in building an automated nematode taxonomy system for nematologists. It is effective to classify multi-focal image stacks. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. New false color mapping for image fusion

    NARCIS (Netherlands)

    Toet, A.; Walraven, J.

    1996-01-01

    A pixel based colour mapping algorithm is presented that produces a fused false colour rendering of two gray level images representing different sensor modalities. The result-ing fused false colour images have a higher information content than each of the original images and retain sensor-specific

  4. SAR Data Fusion Imaging Method Oriented to Target Feature Extraction

    Directory of Open Access Journals (Sweden)

    Yang Wei

    2015-02-01

    Full Text Available To deal with the difficulty for target outlines extracting precisely due to neglect of target scattering characteristic variation during the processing of high-resolution space-borne SAR data, a novel fusion imaging method is proposed oriented to target feature extraction. Firstly, several important aspects that affect target feature extraction and SAR image quality are analyzed, including curved orbit, stop-and-go approximation, atmospheric delay, and high-order residual phase error. Furthermore, the corresponding compensation methods are addressed as well. Based on the analysis, the mathematical model of SAR echo combined with target space-time spectrum is established for explaining the space-time-frequency change rule of target scattering characteristic. Moreover, a fusion imaging strategy and method under high-resolution and ultra-large observation angle range conditions are put forward to improve SAR quality by fusion processing in range-doppler and image domain. Finally, simulations based on typical military targets are used to verify the effectiveness of the fusion imaging method.

  5. Interleaving cerebral CT perfusion with neck CT angiography. Pt. II. Clinical implementation and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Oei, Marcel T.H.; Meijer, Frederick J.A.; Woude, Willem-Jan van der; Smit, Ewoud J.; Ginneken, Bram van; Manniesing, Rashindra; Prokop, Mathias [Radboud University Medical Centre, Department of Radiology and Nuclear Medicine, P.O. Box 9101, Nijmegen (Netherlands)

    2017-06-15

    Feasibility evaluation of the One-Step Stroke Protocol, which is an interleaved cerebral computed tomography perfusion (CTP) and neck volumetric computed tomography angiography (vCTA) scanning technique using wide-detector computed tomography, and to assess the image quality of vCTA. Twenty patients with suspicion of acute ischaemic stroke were prospectively scanned and evaluated with a head and neck CTA and with the One-Step Stroke Protocol. Arterial enhancement and contrast-to-noise ratio (CNR) in the carotid arteries was assessed. Three observers scored artefacts and image quality of the cervical arteries. The total z-coverage was evaluated. Mean enhancement in the carotid bifurcation was rated higher in the vCTA (595 ± 164 HU) than CTA (441 ± 117 HU). CNR was rated higher in vCTA. Image quality scores showed no significant difference in the region of the carotid bifurcation between vCTA and CTA. Lower neck image quality scores were slightly lower for vCTA due to artefacts, although not rated as diagnostically relevant. In ten patients, the origin of the left common carotid artery was missed by 1.6 ± 0.8 cm. Mean patient height was 1.8 ± 0.09 m. Carotid bifurcation and origin of vertebral arteries were covered in all patients. The One-Step Stroke Protocol is feasible with good diagnostic image quality of vCTA, although full z-coverage is limited in tall patients. (orig.)

  6. Influence of adaptive statistical iterative reconstruction algorithm on image quality in coronary computed tomography angiography.

    Science.gov (United States)

    Precht, Helle; Thygesen, Jesper; Gerke, Oke; Egstrup, Kenneth; Waaler, Dag; Lambrechtsen, Jess

    2016-12-01

    Coronary computed tomography angiography (CCTA) requires high spatial and temporal resolution, increased low contrast resolution for the assessment of coronary artery stenosis, plaque detection, and/or non-coronary pathology. Therefore, new reconstruction algorithms, particularly iterative reconstruction (IR) techniques, have been developed in an attempt to improve image quality with no cost in radiation exposure. To evaluate whether adaptive statistical iterative reconstruction (ASIR) enhances perceived image quality in CCTA compared to filtered back projection (FBP). Thirty patients underwent CCTA due to suspected coronary artery disease. Images were reconstructed using FBP, 30% ASIR, and 60% ASIR. Ninety image sets were evaluated by five observers using the subjective visual grading analysis (VGA) and assessed by proportional odds modeling. Objective quality assessment (contrast, noise, and the contrast-to-noise ratio [CNR]) was analyzed with linear mixed effects modeling on log-transformed data. The need for ethical approval was waived by the local ethics committee as the study only involved anonymously collected clinical data. VGA showed significant improvements in sharpness by comparing FBP with ASIR, resulting in odds ratios of 1.54 for 30% ASIR and 1.89 for 60% ASIR ( P  = 0.004). The objective measures showed significant differences between FBP and 60% ASIR ( P  < 0.0001) for noise, with an estimated ratio of 0.82, and for CNR, with an estimated ratio of 1.26. ASIR improved the subjective image quality of parameter sharpness and, objectively, reduced noise and increased CNR.

  7. Image fusion using sparse overcomplete feature dictionaries

    Science.gov (United States)

    Brumby, Steven P.; Bettencourt, Luis; Kenyon, Garrett T.; Chartrand, Rick; Wohlberg, Brendt

    2015-10-06

    Approaches for deciding what individuals in a population of visual system "neurons" are looking for using sparse overcomplete feature dictionaries are provided. A sparse overcomplete feature dictionary may be learned for an image dataset and a local sparse representation of the image dataset may be built using the learned feature dictionary. A local maximum pooling operation may be applied on the local sparse representation to produce a translation-tolerant representation of the image dataset. An object may then be classified and/or clustered within the translation-tolerant representation of the image dataset using a supervised classification algorithm and/or an unsupervised clustering algorithm.

  8. Real-time image fusion involving diagnostic ultrasound

    DEFF Research Database (Denmark)

    Ewertsen, Caroline; Săftoiu, Adrian; Gruionu, Lucian G

    2013-01-01

    The aim of our article is to give an overview of the current and future possibilities of real-time image fusion involving ultrasound. We present a review of the existing English-language peer-reviewed literature assessing this technique, which covers technical solutions (for ultrasound...

  9. Performance comparison of different graylevel image fusion schemes through a universal image quality index

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2003-01-01

    We applied a recently introduced universal image quality index Q that quantifies the distortion of a processed image relative to its original version, to assess the performance of different graylevel image fusion schemes. The method is as follows. First, we adopt an original test image as the

  10. Multimodality imaging of reporter gene expression using a novel fusion vector in living cells and animals

    Science.gov (United States)

    Gambhir, Sanjiv [Portola Valley, CA; Pritha, Ray [Mountain View, CA

    2011-06-07

    Novel double and triple fusion reporter gene constructs harboring distinct imagable reporter genes are provided, as well as applications for the use of such double and triple fusion constructs in living cells and in living animals using distinct imaging technologies.

  11. Perceptual evaluation of different image fusion schemes

    NARCIS (Netherlands)

    Toet, A.; IJspeert, J.K.

    2001-01-01

    Human perceptual performance was tested with images of nighttime outdoor scenes. The scenes were registered both with a dual band (visual and near infrared) image intensified low-light CCD camera (DII) and with a thermal middle wavelength band (3-5 μm) infrared (IR) camera. Fused imagery was

  12. Perceptual evaluation of different image fusion schemes

    NARCIS (Netherlands)

    Toet, A.; Franken, E.M.

    2003-01-01

    Human scene recognition performance was tested with images of night-time outdoor scenes. The scenes were registered both with a dual band (visual and near infrared) image intensified low-light CCD camera (DII) and with a thermal middle wavelength band (3–5 mm) infrared (IR) camera. Fused imagery was

  13. Coherence imaging spectro-polarimetry for magnetic fusion diagnostics

    International Nuclear Information System (INIS)

    Howard, J

    2010-01-01

    This paper presents an overview of developments in imaging spectro-polarimetry for magnetic fusion diagnostics. Using various multiplexing strategies, it is possible to construct optical polarization interferometers that deliver images of underlying physical parameters such as flow speed, temperature (Doppler effect) or magnetic pitch angle (motional Stark and Zeeman effects). This paper also describes and presents first results for a new spatial heterodyne interferometric system used for both Doppler and polarization spectroscopy.

  14. Image Fusion Technologies In Commercial Remote Sensing Packages

    OpenAIRE

    Al-Wassai, Firouz Abdullah; Kalyankar, N. V.

    2013-01-01

    Several remote sensing software packages are used to the explicit purpose of analyzing and visualizing remotely sensed data, with the developing of remote sensing sensor technologies from last ten years. Accord-ing to literature, the remote sensing is still the lack of software tools for effective information extraction from remote sensing data. So, this paper provides a state-of-art of multi-sensor image fusion technologies as well as review on the quality evaluation of the single image or f...

  15. Creating vascular models by postprocessing computed tomography angiography images: a guide for anatomical education.

    Science.gov (United States)

    Govsa, Figen; Ozer, Mehmet Asim; Sirinturk, Suzan; Eraslan, Cenk; Alagoz, Ahmet Kemal

    2017-08-01

    A new application of teaching anatomy includes the use of computed tomography angiography (CTA) images to create clinically relevant three-dimensional (3D) printed models. The purpose of this article is to review recent innovations on the process and the application of 3D printed models as a tool for using under and post-graduate medical education. Images of aortic arch pattern received by CTA were converted into 3D images using the Google SketchUp free software and were saved in stereolithography format. Using a 3D printer (Makerbot), a model mode polylactic acid material was printed. A two-vessel left aortic arch was identified consisting of the brachiocephalic trunk and left subclavian artery. The life-like 3D models were rotated 360° in all axes in hand. The early adopters in education and clinical practices have embraced the medical imaging-guided 3D printed anatomical models for their ability to provide tactile feedback and a superior appreciation of visuospatial relationship between the anatomical structures. Printed vascular models are used to assist in preoperative planning, develop intraoperative guidance tools, and to teach patients surgical trainees in surgical practice.

  16. Echo-planar MR imaging of dissolved hyperpolarized 129Xe. Potential for M angiography

    International Nuclear Information System (INIS)

    Maansson, S.

    2002-01-01

    Purpose: The feasibility of hyperpolarized 129 Xe for fast MR angiography (MRA) was evaluated using the echo-planar imaging (EPI) technique. Material and Methods: Hyperpolarized Xe gas was dissolved in ethanol; a carrier agent with high solubility for Xe (Ostwald solubility coefficient 2.5) and long relaxation times. The dissolved Xe was injected as a bolus into a flow phantom where the mean flow velocity was 15 cm/s. Ultrafast EPI images with 44 ms scan time were acquired of the flowing bolus and the signal-to-noise ratios (SNR) were measured. Results: The relaxation times of hyperpolarized Xe in ethanol were measured to T1=160±11 s and T2 ≅ 20 s. The resulting images of the flowing liquid were of reasonable quality and had an SNR of about 70. Conclusion: Based on the SNR of the obtained Xe EPI images; it was estimated that rapid in vivo MRA with 129 Xe may be feasible; provided that an efficient; biologically acceptable carrier for Xe can be found and polarization levels of more than 25% can be achieved in isotopically enriched 129 Xe

  17. Visualization of Radial Peripapillary Capillaries Using Optical Coherence Tomography Angiography: The Effect of Image Averaging.

    Directory of Open Access Journals (Sweden)

    Shelley Mo

    Full Text Available To assess the effect of image registration and averaging on the visualization and quantification of the radial peripapillary capillary (RPC network on optical coherence tomography angiography (OCTA.Twenty-two healthy controls were imaged with a commercial OCTA system (AngioVue, Optovue, Inc.. Ten 10x10° scans of the optic disc were obtained, and the most superficial layer (50-μm slab extending from the inner limiting membrane was extracted for analysis. Rigid registration was achieved using ImageJ, and averaging of each 2 to 10 frames was performed in five ~2x2° regions of interest (ROI located 1° from the optic disc margin. The ROI were automatically skeletonized. Signal-to-noise ratio (SNR, number of endpoints and mean capillary length from the skeleton, capillary density, and mean intercapillary distance (ICD were measured for the reference and each averaged ROI. Repeated measures analysis of variance was used to assess statistical significance. Three patients with primary open angle glaucoma were also imaged to compare RPC density to controls.Qualitatively, vessels appeared smoother and closer to histologic descriptions with increasing number of averaged frames. Quantitatively, number of endpoints decreased by 51%, and SNR, mean capillary length, capillary density, and ICD increased by 44%, 91%, 11%, and 4.5% from single frame to 10-frame averaged, respectively. The 10-frame averaged images from the glaucomatous eyes revealed decreased density correlating to visual field defects and retinal nerve fiber layer thinning.OCTA image registration and averaging is a viable and accessible method to enhance the visualization of RPCs, with significant improvements in image quality and RPC quantitative parameters. With this technique, we will be able to non-invasively and reliably study RPC involvement in diseases such as glaucoma.

  18. Reconstruction-of-difference (RoD) imaging for cone-beam CT neuro-angiography

    Science.gov (United States)

    Wu, P.; Stayman, J. W.; Mow, M.; Zbijewski, W.; Sisniega, A.; Aygun, N.; Stevens, R.; Foos, D.; Wang, X.; Siewerdsen, J. H.

    2018-06-01

    Timely evaluation of neurovasculature via CT angiography (CTA) is critical to the detection of pathology such as ischemic stroke. Cone-beam CTA (CBCT-A) systems provide potential advantages in the timely use at the point-of-care, although challenges of a relatively slow gantry rotation speed introduce tradeoffs among image quality, data consistency and data sparsity. This work describes and evaluates a new reconstruction-of-difference (RoD) approach that is robust to such challenges. A fast digital simulation framework was developed to test the performance of the RoD over standard reference reconstruction methods such as filtered back-projection (FBP) and penalized likelihood (PL) over a broad range of imaging conditions, grouped into three scenarios to test the trade-off between data consistency, data sparsity and peak contrast. Two experiments were also conducted using a CBCT prototype and an anthropomorphic neurovascular phantom to test the simulation findings in real data. Performance was evaluated primarily in terms of normalized root mean square error (NRMSE) in comparison to truth, with reconstruction parameters chosen to optimize performance in each case to ensure fair comparison. The RoD approach reduced NRMSE in reconstructed images by up to 50%–53% compared to FBP and up to 29%–31% compared to PL for each scenario. Scan protocols well suited to the RoD approach were identified that balance tradeoffs among data consistency, sparsity and peak contrast—for example, a CBCT-A scan with 128 projections acquired in 8.5 s over a 180°  +  fan angle half-scan for a time attenuation curve with ~8.5 s time-to-peak and 600 HU peak contrast. With imaging conditions such as the simulation scenarios of fixed data sparsity (i.e. varying levels of data consistency and peak contrast), the experiments confirmed the reduction of NRMSE by 34% and 17% compared to FBP and PL, respectively. The RoD approach demonstrated superior performance in 3D angiography

  19. Cardiovascular CT angiography in neonates and children: Image quality and potential for radiation dose reduction with iterative image reconstruction techniques

    International Nuclear Information System (INIS)

    Tricarico, Francesco; Hlavacek, Anthony M.; Schoepf, U.J.; Ebersberger, Ullrich; Nance, John W.; Vliegenthart, Rozemarijn; Cho, Young Jun; Spears, J.R.; Secchi, Francesco; Savino, Giancarlo; Marano, Riccardo; Bonomo, Lorenzo; Schoenberg, Stefan O.; Apfaltrer, Paul

    2013-01-01

    To evaluate image quality (IQ) of low-radiation-dose paediatric cardiovascular CT angiography (CTA), comparing iterative reconstruction in image space (IRIS) and sinogram-affirmed iterative reconstruction (SAFIRE) with filtered back-projection (FBP) and estimate the potential for further dose reductions. Forty neonates and children underwent low radiation CTA with or without ECG synchronisation. Data were reconstructed with FBP, IRIS and SAFIRE. For ECG-synchronised studies, half-dose image acquisitions were simulated. Signal noise was measured and IQ graded. Effective dose (ED) was estimated. Mean absolute and relative image noise with IRIS and full-dose SAFIRE was lower than with FBP (P < 0.001), while SNR and CNR were higher (P < 0.001). Image noise was also lower and SNR and CNR higher in half-dose SAFIRE studies compared with full-and half-dose FBP studies (P < 0.001). IQ scores were higher for IRIS, full-dose SAFIRE and half-dose SAFIRE than for full-dose FBP and higher for half-dose SAFIRE than for half-dose FBP (P < 0.05). Median weight-specific ED was 0.3 mSv without and 1.36 mSv with ECG synchronisation. The estimated ED of half-dose SAFIRE studies was 0.68 mSv. IR improves image noise, SNR, CNR and subjective IQ compared with FBP in low-radiation-dose paediatric CTA and allows further dose reductions without compromising diagnostic IQ. (orig.)

  20. Cardiovascular CT angiography in neonates and children: Image quality and potential for radiation dose reduction with iterative image reconstruction techniques

    Energy Technology Data Exchange (ETDEWEB)

    Tricarico, Francesco [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); Catholic University of the Sacred Heart, ' ' A. Gemelli' ' Hospital, Department of Bioimaging and Radiological Sciences, Rome (Italy); Hlavacek, Anthony M. [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); Children' s Hospital, Medical University of South Carolina, Division of Pediatric Cardiology, Charleston, SC (United States); Schoepf, U.J. [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); Children' s Hospital, Medical University of South Carolina, Division of Pediatric Cardiology, Charleston, SC (United States); Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Ebersberger, Ullrich [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); Heart Centre Munich-Bogenhausen, Department of Cardiology and Intensive Care Medicine, Munich (Germany); Nance, John W. [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); Johns Hopkins Hospital, The Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, MD (United States); Vliegenthart, Rozemarijn [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); University Medical Centre Groningen/University of Groningen, Centre for Medical Imaging - North East Netherlands, Department of Radiology, Groningen (Netherlands); Cho, Young Jun [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); Konyang University School of Medicine, Department of Radiology, Daejeon (Korea, Republic of); Spears, J.R. [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); Secchi, Francesco [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Milan School of Medicine IRCCS Policlinico San Donato, Department of Medical and Surgical Sciences, Radiology Unit, Milan (Italy); Savino, Giancarlo; Marano, Riccardo; Bonomo, Lorenzo [Catholic University of the Sacred Heart, ' ' A. Gemelli' ' Hospital, Department of Bioimaging and Radiological Sciences, Rome (Italy); Schoenberg, Stefan O. [University Medical Centre Mannheim, Medical Faculty Mannheim - Heidelberg University, Institute of Clinical Radiology and Nuclear Medicine, Mannheim (Germany); Apfaltrer, Paul [Medical University of South Carolina, Ashley River Tower, Department of Radiology and Radiological Science, Charleston, SC (United States); University Medical Centre Mannheim, Medical Faculty Mannheim - Heidelberg University, Institute of Clinical Radiology and Nuclear Medicine, Mannheim (Germany)

    2013-05-15

    To evaluate image quality (IQ) of low-radiation-dose paediatric cardiovascular CT angiography (CTA), comparing iterative reconstruction in image space (IRIS) and sinogram-affirmed iterative reconstruction (SAFIRE) with filtered back-projection (FBP) and estimate the potential for further dose reductions. Forty neonates and children underwent low radiation CTA with or without ECG synchronisation. Data were reconstructed with FBP, IRIS and SAFIRE. For ECG-synchronised studies, half-dose image acquisitions were simulated. Signal noise was measured and IQ graded. Effective dose (ED) was estimated. Mean absolute and relative image noise with IRIS and full-dose SAFIRE was lower than with FBP (P < 0.001), while SNR and CNR were higher (P < 0.001). Image noise was also lower and SNR and CNR higher in half-dose SAFIRE studies compared with full-and half-dose FBP studies (P < 0.001). IQ scores were higher for IRIS, full-dose SAFIRE and half-dose SAFIRE than for full-dose FBP and higher for half-dose SAFIRE than for half-dose FBP (P < 0.05). Median weight-specific ED was 0.3 mSv without and 1.36 mSv with ECG synchronisation. The estimated ED of half-dose SAFIRE studies was 0.68 mSv. IR improves image noise, SNR, CNR and subjective IQ compared with FBP in low-radiation-dose paediatric CTA and allows further dose reductions without compromising diagnostic IQ. (orig.)

  1. On the technique of digital X-ray image processing, especially of digital substraction angiography

    International Nuclear Information System (INIS)

    Pfeiler, M.; Marhoff, P.

    1983-01-01

    Digital radiography, especially in the form of subtraction angiography, has found special consideration during the last two years as could be noted at many radiological conventions. Also a series of symposia was especially devoted to this subject. The extensive picture material shown at these conventions does not only document an important extension of the fields of application, but also an important increment in clinical and technical experience. Two pictures may represent many other examples: with a time lag of less than one year the improvement of objective and subjective image quality is easy to recognize. The principle and the technology of digital radiography were demonstrated at these conventions as well as in this magazine, and they also were discussed in detail; therefore a comprehensive review with only a few concepts necessary for defining the topic is sufficient here. Of the different imaging techniques, the fluorographic and the pulsed operation techniques are discussed, especially with regard to the storage method used. The definition of these concepts follows later. Special emphasis is put on some considerations of the signal-to-noise ratio that represents an essential criterion of the image quality. (orig.) [de

  2. Enhanced EDX images by fusion of multimodal SEM images using pansharpening techniques.

    Science.gov (United States)

    Franchi, G; Angulo, J; Moreaud, M; Sorbier, L

    2018-01-01

    The goal of this paper is to explore the potential interest of image fusion in the context of multimodal scanning electron microscope (SEM) imaging. In particular, we aim at merging the backscattered electron images that usually have a high spatial resolution but do not provide enough discriminative information to physically classify the nature of the sample, with energy-dispersive X-ray spectroscopy (EDX) images that have discriminative information but a lower spatial resolution. The produced images are named enhanced EDX. To achieve this goal, we have compared the results obtained with classical pansharpening techniques for image fusion with an original approach tailored for multimodal SEM fusion of information. Quantitative assessment is obtained by means of two SEM images and a simulated dataset produced by a software based on PENELOPE. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  3. Phantom-based standardization of CT angiography images for spot sign detection.

    Science.gov (United States)

    Morotti, Andrea; Romero, Javier M; Jessel, Michael J; Hernandez, Andrew M; Vashkevich, Anastasia; Schwab, Kristin; Burns, Joseph D; Shah, Qaisar A; Bergman, Thomas A; Suri, M Fareed K; Ezzeddine, Mustapha; Kirmani, Jawad F; Agarwal, Sachin; Shapshak, Angela Hays; Messe, Steven R; Venkatasubramanian, Chitra; Palmieri, Katherine; Lewandowski, Christopher; Chang, Tiffany R; Chang, Ira; Rose, David Z; Smith, Wade; Hsu, Chung Y; Liu, Chun-Lin; Lien, Li-Ming; Hsiao, Chen-Yu; Iwama, Toru; Afzal, Mohammad Rauf; Cassarly, Christy; Greenberg, Steven M; Martin, Renee' Hebert; Qureshi, Adnan I; Rosand, Jonathan; Boone, John M; Goldstein, Joshua N

    2017-09-01

    The CT angiography (CTA) spot sign is a strong predictor of hematoma expansion in intracerebral hemorrhage (ICH). However, CTA parameters vary widely across centers and may negatively impact spot sign accuracy in predicting ICH expansion. We developed a CT iodine calibration phantom that was scanned at different institutions in a large multicenter ICH clinical trial to determine the effect of image standardization on spot sign detection and performance. A custom phantom containing known concentrations of iodine was designed and scanned using the stroke CT protocol at each institution. Custom software was developed to read the CT volume datasets and calculate the Hounsfield unit as a function of iodine concentration for each phantom scan. CTA images obtained within 8 h from symptom onset were analyzed by two trained readers comparing the calibrated vs. uncalibrated density cutoffs for spot sign identification. ICH expansion was defined as hematoma volume growth >33%. A total of 90 subjects qualified for the study, of whom 17/83 (20.5%) experienced ICH expansion. The number of spot sign positive scans was higher in the calibrated analysis (67.8 vs 38.9% p spot signs identified in the non-calibrated analysis remained positive after calibration. Calibrated CTA images had higher sensitivity for ICH expansion (76 vs 52%) but inferior specificity (35 vs 63%) compared with uncalibrated images. Normalization of CTA images using phantom data is a feasible strategy to obtain consistent image quantification for spot sign analysis across different sites and may improve sensitivity for identification of ICH expansion.

  4. Phantom-based standardization of CT angiography images for spot sign detection

    International Nuclear Information System (INIS)

    Morotti, Andrea; Rosand, Jonathan; Romero, Javier M.; Jessel, Michael J.; Vashkevich, Anastasia; Schwab, Kristin; Greenberg, Steven M.; Hernandez, Andrew M.; Boone, John M.; Burns, Joseph D.; Shah, Qaisar A.; Bergman, Thomas A.; Suri, M.F.K.; Ezzeddine, Mustapha; Kirmani, Jawad F.; Agarwal, Sachin; Hays Shapshak, Angela; Messe, Steven R.; Venkatasubramanian, Chitra; Palmieri, Katherine; Lewandowski, Christopher; Chang, Tiffany R.; Chang, Ira; Rose, David Z.; Smith, Wade; Hsu, Chung Y.; Liu, Chun-Lin; Lien, Li-Ming; Hsiao, Chen-Yu; Iwama, Toru; Afzal, Mohammad Rauf; Qureshi, Adnan I.; Cassarly, Christy; Hebert Martin, Renee; Goldstein, Joshua N.

    2017-01-01

    The CT angiography (CTA) spot sign is a strong predictor of hematoma expansion in intracerebral hemorrhage (ICH). However, CTA parameters vary widely across centers and may negatively impact spot sign accuracy in predicting ICH expansion. We developed a CT iodine calibration phantom that was scanned at different institutions in a large multicenter ICH clinical trial to determine the effect of image standardization on spot sign detection and performance. A custom phantom containing known concentrations of iodine was designed and scanned using the stroke CT protocol at each institution. Custom software was developed to read the CT volume datasets and calculate the Hounsfield unit as a function of iodine concentration for each phantom scan. CTA images obtained within 8 h from symptom onset were analyzed by two trained readers comparing the calibrated vs. uncalibrated density cutoffs for spot sign identification. ICH expansion was defined as hematoma volume growth >33%. A total of 90 subjects qualified for the study, of whom 17/83 (20.5%) experienced ICH expansion. The number of spot sign positive scans was higher in the calibrated analysis (67.8 vs 38.9% p < 0.001). All spot signs identified in the non-calibrated analysis remained positive after calibration. Calibrated CTA images had higher sensitivity for ICH expansion (76 vs 52%) but inferior specificity (35 vs 63%) compared with uncalibrated images. Normalization of CTA images using phantom data is a feasible strategy to obtain consistent image quantification for spot sign analysis across different sites and may improve sensitivity for identification of ICH expansion. (orig.)

  5. Phantom-based standardization of CT angiography images for spot sign detection

    Energy Technology Data Exchange (ETDEWEB)

    Morotti, Andrea; Rosand, Jonathan [Harvard Medical School, Division of Neurocritical Care and Emergency Neurology, Department of Neurology, Massachusetts General Hospital, Boston, MA (United States); Harvard Medical School, J. P. Kistler Stroke Research Center, Massachusetts General Hospital, Boston, MA (United States); Romero, Javier M. [Harvard Medical School, Division of Neurocritical Care and Emergency Neurology, Department of Neurology, Massachusetts General Hospital, Boston, MA (United States); Harvard Medical School, J. P. Kistler Stroke Research Center, Massachusetts General Hospital, Boston, MA (United States); Harvard Medical School, Neuroradiology Service, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Jessel, Michael J.; Vashkevich, Anastasia; Schwab, Kristin; Greenberg, Steven M. [Harvard Medical School, J. P. Kistler Stroke Research Center, Massachusetts General Hospital, Boston, MA (United States); Hernandez, Andrew M.; Boone, John M. [University of California Davis, Department of Radiology, Sacramento, CA (United States); Burns, Joseph D. [Lahey Hospital and Medical Center, Department of Neurology, Burlington, MA (United States); Shah, Qaisar A. [Abington Memorial Hospital, Abington, PA (United States); Bergman, Thomas A. [Hennepin County Medical Center, Minneapolis, MN (United States); Suri, M.F.K. [St. Cloud Hospital, St. Cloud, MN (United States); Ezzeddine, Mustapha [University of Minnesota, Minneapolis, MN (United States); Kirmani, Jawad F. [JFK Medical Center, Stroke and Neurovascular Center, Edison, NJ (United States); Agarwal, Sachin [Columbia University Medical Center, New York, NY (United States); Hays Shapshak, Angela [University of Alabama at Birmingham, Birmingham, AL (United States); Messe, Steven R. [University of Pennsylvania, Philadelphia, PA (United States); Venkatasubramanian, Chitra [Stanford University, Stanford, CA (United States); Palmieri, Katherine [The University of Kansas Health System, Kansas City, KS (United States); Lewandowski, Christopher [Henry Ford Hospital, Detroit, MI (United States); Chang, Tiffany R. [University of Texas Medical School, Houston, TX (United States); Chang, Ira [Colorado Neurological Institute, Swedish Medical Center, Englewood, CO (United States); Rose, David Z. [Tampa General Hospital, University of South Florida College of Medicine, Tampa, FL (United States); Smith, Wade [UCSF Medical Center, San Francisco, CA (United States); Hsu, Chung Y.; Liu, Chun-Lin [China Medical University Hospital, Taichung (China); Lien, Li-Ming; Hsiao, Chen-Yu [Shin Kong Wu Ho-Su Memorial Hospital, Taipei (China); Iwama, Toru [Gifu University Hospital, Gifu (Japan); Afzal, Mohammad Rauf; Qureshi, Adnan I. [University of Minnesota, Zeenat Qureshi Stroke Research Center, Minneapolis, MN (United States); Cassarly, Christy; Hebert Martin, Renee [Medical University of South Carolina, Department of Public Health Sciences, Charleston, SC (United States); Goldstein, Joshua N. [Harvard Medical School, Division of Neurocritical Care and Emergency Neurology, Department of Neurology, Massachusetts General Hospital, Boston, MA (United States); Harvard Medical School, J. P. Kistler Stroke Research Center, Massachusetts General Hospital, Boston, MA (United States); Harvard Medical School, Department of Emergency Medicine, Massachusetts General Hospital, Boston, MA (United States); Collaboration: ATACH-II and NETT Investigators

    2017-09-15

    The CT angiography (CTA) spot sign is a strong predictor of hematoma expansion in intracerebral hemorrhage (ICH). However, CTA parameters vary widely across centers and may negatively impact spot sign accuracy in predicting ICH expansion. We developed a CT iodine calibration phantom that was scanned at different institutions in a large multicenter ICH clinical trial to determine the effect of image standardization on spot sign detection and performance. A custom phantom containing known concentrations of iodine was designed and scanned using the stroke CT protocol at each institution. Custom software was developed to read the CT volume datasets and calculate the Hounsfield unit as a function of iodine concentration for each phantom scan. CTA images obtained within 8 h from symptom onset were analyzed by two trained readers comparing the calibrated vs. uncalibrated density cutoffs for spot sign identification. ICH expansion was defined as hematoma volume growth >33%. A total of 90 subjects qualified for the study, of whom 17/83 (20.5%) experienced ICH expansion. The number of spot sign positive scans was higher in the calibrated analysis (67.8 vs 38.9% p < 0.001). All spot signs identified in the non-calibrated analysis remained positive after calibration. Calibrated CTA images had higher sensitivity for ICH expansion (76 vs 52%) but inferior specificity (35 vs 63%) compared with uncalibrated images. Normalization of CTA images using phantom data is a feasible strategy to obtain consistent image quantification for spot sign analysis across different sites and may improve sensitivity for identification of ICH expansion. (orig.)

  6. Radiation exposure in X-ray angiography and comparisons between digital and conventional methods of imaging

    International Nuclear Information System (INIS)

    Schaberg, J.

    1987-01-01

    The more recent developments and techniques in the field of angiography are examined for associated radiation exposure risks for patients and investigators and then compared to the conventional methods of angiography. It could be shown that digital subtraction angiography is generally associated with a lesser risk of somatic exposure of the patient, provided that the equipment used offers an adjustable useful-beam range and focus. The fact that above-table X-ray tubes are now generally replaced with X-ray systems installed under the examination table permits the relatively high doses, to which investigators are exposed during angiography, to be reduced by a factor of 3. (DG) [de

  7. A Geometric Dictionary Learning Based Approach for Fluorescence Spectroscopy Image Fusion

    OpenAIRE

    Zhiqin Zhu; Guanqiu Qi; Yi Chai; Penghua Li

    2017-01-01

    In recent years, sparse representation approaches have been integrated into multi-focus image fusion methods. The fused images of sparse-representation-based image fusion methods show great performance. Constructing an informative dictionary is a key step for sparsity-based image fusion method. In order to ensure sufficient number of useful bases for sparse representation in the process of informative dictionary construction, image patches from all source images are classified into different ...

  8. Multimodality Image Fusion and Planning and Dose Delivery for Radiation Therapy

    International Nuclear Information System (INIS)

    Saw, Cheng B.; Chen Hungcheng; Beatty, Ron E.; Wagner, Henry

    2008-01-01

    Image-guided radiation therapy (IGRT) relies on the quality of fused images to yield accurate and reproducible patient setup prior to dose delivery. The registration of 2 image datasets can be characterized as hardware-based or software-based image fusion. Hardware-based image fusion is performed by hybrid scanners that combine 2 distinct medical imaging modalities such as positron emission tomography (PET) and computed tomography (CT) into a single device. In hybrid scanners, the patient maintains the same position during both studies making the fusion of image data sets simple. However, it cannot perform temporal image registration where image datasets are acquired at different times. On the other hand, software-based image fusion technique can merge image datasets taken at different times or with different medical imaging modalities. Software-based image fusion can be performed either manually, using landmarks, or automatically. In the automatic image fusion method, the best fit is evaluated using mutual information coefficient. Manual image fusion is typically performed at dose planning and for patient setup prior to dose delivery for IGRT. The fusion of orthogonal live radiographic images taken prior to dose delivery to digitally reconstructed radiographs will be presented. Although manual image fusion has been routinely used, the use of fiducial markers has shortened the fusion time. Automated image fusion should be possible for IGRT because the image datasets are derived basically from the same imaging modality, resulting in further shortening the fusion time. The advantages and limitations of both hardware-based and software-based image fusion methodologies are discussed

  9. 16-slice multi-detector row CT coronary angiography: image quality and optimization of the image reconstruction window

    International Nuclear Information System (INIS)

    Kim, Yoo Kyung; Shim, Sung Shine; Lim, Soo Mee; Hwang, Ji Young; Kim, Yoon Kyung

    2005-01-01

    The purpose of this experiment is to investigate the image quality of CT coronary angiography using a 16-slice multi-detector row CT and to determine the optimal image reconstruction window. CT coronary angiography was obtained in 36 nonsymptomatic volunteers using a 16-slice multi-detector row CT (SOMATOM Sensation, Siemens Medical System). The mean heart rates were 70 beats per minute (bpm) or less in 18 persons and more than 70 bpm in 18 persons. Eleven data sets were obtained for each patient (reconstructed at 30%-80% of the cardiac cycle with an increment of 5%). Image quality of the eight coronary segments [left main coronary artery (LM), proximal and middle segments of left anterior descending artery (p-LAD, m-LAN) and left circumflex coronary artery (p-LCx, m-LCx) and proximal, middle and distal segments of right coronary artery (p-RCA, m-RCA, d-RCA)] was assessed. The optimal reconstruction windows in the cardiac cycle for the best image quality were 60-70% for the segments of the LM, LAD, and LC arteries in two groups (bpm 70) and 55-65% (bpm 70) for the segments of the RCA. On the best dataset for each coronary segment, the following diagnostic image quality was achieved in the two groups: LM: 100%, 83%; p-LAD: 100%, 88% m-LAD: 100%, 72%; p-LCx: 100%, 72%; m-LCx: 100%, 72%; p-RCA: 94%, 72%; m-RCA: 61%, 50%; d-RCA: 100%, 80%. The 16 slice multi-detector row CT scan provided visualization of the coronary arteries with high resolution. Especially in the group with a mean heart rate of 70 bpm or less, all the coronary segments except the RCA showed diagnostic image quality. Optimal image quality was achieved with a 60-70% trigger delay for all coronary arterial segments, but the best images of RCA were achieved in the earlier cardiac phase in the patients with a mean heart rate of more than 70 bpm

  10. Effects of ionic and nonionic contrast media on cardiohemodynamics and quality of radiographic image during canine angiography

    International Nuclear Information System (INIS)

    Nakamura, H.; Kurata, M.; Haruta, K.; Takeda, K.

    1994-01-01

    Cardiovascular responses and radiographic image quality during cerebral angiography, aortofemoral angiography and left ventriculography with nonionic ioxilan, iohexol or iopamidol were compared with those of ionic sodium meglumine diatrizoate in pentobarbital anesthetized dogs. Injection of all contrast media caused cardiovascular changes to a greater or lesser degree, e.g., hypotension, bradycardia, tachycardia, a decrease in left ventricular pressure (LVP) and its first derivative (dP/dt), and prolongation of the P-Q and Q-T intervals. Ionic diatrizoate had a greater effect on cardiovascular parameters than nonionic contrast media during angiography in all areas. Moreover, diatrizoate produced cardiac arrhythmias and prominent changes in blood rheology concerned with blood viscosity and deformability of the erythrocyte. The cause of various effects of contrast media seemed to lie mainly in osmolality, viscosity and partially ionic additives. The radiographic image quality of all of the contrast media used was similar, but nonionic ioxilan and iohexol with lower iodine content and low osmolality gave better radio opacity than ionic diatrizoate in cerebral angiography. These results suggested that nonionic contrast media should be recommended as a diagnostic tool for both animals and human patients in poor health

  11. Color image fusion for concealed weapon detection

    NARCIS (Netherlands)

    Toet, A.

    2003-01-01

    Recent advances in passive and active imaging sensor technology offer the potential to detect weapons that are concealed underneath a person's clothing or carried along in bags. Although the concealed weapons can sometimes easily be detected, it can be difficult to perceive their context, due to the

  12. Implementation of a channelized Hotelling observer model to assess image quality of x-ray angiography systems.

    Science.gov (United States)

    Favazza, Christopher P; Fetterly, Kenneth A; Hangiandreou, Nicholas J; Leng, Shuai; Schueler, Beth A

    2015-01-01

    Evaluation of flat-panel angiography equipment through conventional image quality metrics is limited by the scope of standard spatial-domain image quality metric(s), such as contrast-to-noise ratio and spatial resolution, or by restricted access to appropriate data to calculate Fourier domain measurements, such as modulation transfer function, noise power spectrum, and detective quantum efficiency. Observer models have been shown capable of overcoming these limitations and are able to comprehensively evaluate medical-imaging systems. We present a spatial domain-based channelized Hotelling observer model to calculate the detectability index (DI) of our different sized disks and compare the performance of different imaging conditions and angiography systems. When appropriate, changes in DIs were compared to expectations based on the classical Rose model of signal detection to assess linearity of the model with quantum signal-to-noise ratio (SNR) theory. For these experiments, the estimated uncertainty of the DIs was less than 3%, allowing for precise comparison of imaging systems or conditions. For most experimental variables, DI changes were linear with expectations based on quantum SNR theory. DIs calculated for the smallest objects demonstrated nonlinearity with quantum SNR theory due to system blur. Two angiography systems with different detector element sizes were shown to perform similarly across the majority of the detection tasks.

  13. Evaluation of carotid vessel wall enhancement with image subtraction after gadobenate dimeglumine-enhanced MR angiography

    International Nuclear Information System (INIS)

    Sardanelli, Francesco; Di Leo, Giovanni; Aliprandi, Alberto; Flor, Nicola; Papini, Giacomo D.E.; Roccatagliata, Luca; Cotticelli, Biagio; Nano, Giovanni; Cornalba, Gianpaolo

    2009-01-01

    Objectives: This study was aimed at testing the value of image subtraction for evaluating carotid vessel wall enhancement in contrast-enhanced MR angiography (MRA). Materials and methods: IRB approval was obtained. The scans of 81 consecutive patients who underwent carotid MRA with 0.1 mmol/kg of gadobenate dimeglumine were reviewed. Axial carotid 3D T1-weighted fast low-angle shot sequence before and 3 min after contrast injection were acquired and subtracted (enhanced minus unenhanced). Vessel wall enhancement was assigned a four-point score using native or subtracted images from 0 (no enhancement) to 3 (strong enhancement). Stenosis degree was graded according to NASCET. Results: With native images, vessel wall enhancement was detected in 20/81 patients (25%) and in 20/161 carotids (12%), and scored 2.0 ± 0.6 (mean ± standard deviation); with subtracted images, in 21/81 (26%) and 22/161 (14%), and scored 2.5 ± 0.6, respectively (P < 0.001, Sign test). The overall stenosis degree distribution was: mild, 41/161 (25%); moderate, 77/161 (48%); severe, 43/161 (27%). Carotids with moderate stenosis showed vessel wall enhancement with a frequency (17/77, 22%) significantly higher than that observed in carotids with mild stenosis (1/41, 2%) (P = 0.005, Fisher exact test) and higher, even though with borderline significance (P = 0.078, Fisher exact test), than that observed in carotids with severe stenosis (4/43, 9%). Conclusion: Roughly a quarter of patients undergoing carotid MRA showed vessel wall enhancement. Image subtraction improved vessel wall enhancement conspicuity. Vessel wall enhancement seems to be an event relatively independent from the degree of stenosis. Further studies are warranted to define the relation between vessel wall enhancement and histopathology, inflammatory status, and instability.

  14. Influence of adaptive statistical iterative reconstruction algorithm on image quality in coronary computed tomography angiography

    Directory of Open Access Journals (Sweden)

    Helle Precht

    2016-12-01

    Full Text Available Background Coronary computed tomography angiography (CCTA requires high spatial and temporal resolution, increased low contrast resolution for the assessment of coronary artery stenosis, plaque detection, and/or non-coronary pathology. Therefore, new reconstruction algorithms, particularly iterative reconstruction (IR techniques, have been developed in an attempt to improve image quality with no cost in radiation exposure. Purpose To evaluate whether adaptive statistical iterative reconstruction (ASIR enhances perceived image quality in CCTA compared to filtered back projection (FBP. Material and Methods Thirty patients underwent CCTA due to suspected coronary artery disease. Images were reconstructed using FBP, 30% ASIR, and 60% ASIR. Ninety image sets were evaluated by five observers using the subjective visual grading analysis (VGA and assessed by proportional odds modeling. Objective quality assessment (contrast, noise, and the contrast-to-noise ratio [CNR] was analyzed with linear mixed effects modeling on log-transformed data. The need for ethical approval was waived by the local ethics committee as the study only involved anonymously collected clinical data. Results VGA showed significant improvements in sharpness by comparing FBP with ASIR, resulting in odds ratios of 1.54 for 30% ASIR and 1.89 for 60% ASIR (P = 0.004. The objective measures showed significant differences between FBP and 60% ASIR (P < 0.0001 for noise, with an estimated ratio of 0.82, and for CNR, with an estimated ratio of 1.26. Conclusion ASIR improved the subjective image quality of parameter sharpness and, objectively, reduced noise and increased CNR.

  15. Image quality and patient exposure in mammography, tomography, angiography, and bone radiography

    International Nuclear Information System (INIS)

    Haus, A.G.; Rossmann, K.; Doi, K.; Chiles, J.T.

    1975-01-01

    In diagnostic radiology, the physical factors affecting image quality and patient exposure are complex and must be studied for each individual procedure. They are a function of recording system unsharpness, geometric unsharpness, image noise, and of the shape, size, and absorption properties of the anatomic part radiographed and the lesion to be detected. The choice of recording system has a significant effect on image quality, and the speed of the recording system is directly related to patient exposure for each procedure. In this presentation, the complexities involved in the selection of recording systems for four radiologic procedures are discussed. We describe in detail our most recent work on mammography with the Lo-Dose system, whereby a significant reduction in exposure may not reduce, but may even increase the diagnostic accuracy by reducing geometric unsharpness. We also describe several examples: (a) in tomography, image resolution is not decreased and diagnostic certainty is affected by a change from a medium-speed screen to a high-speed screen recording system (patient exposure is reduced by a factor of 2); (b) in fine-detail skeletal radiography, the diagnostic information is increased significantly by a change from a conventional screen-film technique to a non-screen technique with fine-grain film and optical magnification, but at the cost of increased patient exposure; and (c) in cerebral angiography, diagnostic information can be increased by use of a screen-film recording system of higher resolution, but lower speed for imaging of small blood vessels. Modulation Transfer Functions and clinical examples are used to illustrate each procedure. (U.S.)

  16. Image quality and patient exposure in mammography, tomography, angiography and bone radiography

    International Nuclear Information System (INIS)

    Haus, A.G.; Rossmann, K.; Doi, K.; Chiles, J.T.

    1975-01-01

    In diagnostic radiology, the physical factors affecting image quality and patient exposure are complex and must be studied for each individual procedure. They are a function of recording system unsharpness, geometric unsharpness, image noise, and of the shape, size, and absorption properties of the anatomic part radiographed and the lesion to be detected. The choice of recording system has a significant effect on image quality, and the speed of the recording system is directly related to patient exposure for each procedure. This paper discusses the complexities involved in the selection of recording systems for four radiologic procedures. The authors describe in detail their most recent work on mammography with the Lo-Dose system, whereby a significant reduction in exposure may not reduce, but may even increase, the diagnostic accuracy by reducing geometric unsharpness. We also describe several examples: (a) in tomography, image resolution is not decreased and diagnostic certainty is affected by a change from a medium-speed screen to a high-speed screen recording system (patient exposure is reduced by a factor of 2); (b) in fine-detail skeletal radiography, the diagnostic information is increased significantly by a change from a conventional screen-film technique to a non-screen technique with fine-grain film and optical magnification, but at the cost of increased patient exposure; and (c) in cerebral angiography, diagnostic information can be increased by use of a screen-film recording system of higher resolution, but lower speed for imaging of small blood vessels. Modulation transfer functions and clinical examples are used to illustrate each procedure. (author)

  17. Spinal fusion-hardware construct: Basic concepts and imaging review

    Science.gov (United States)

    Nouh, Mohamed Ragab

    2012-01-01

    The interpretation of spinal images fixed with metallic hardware forms an increasing bulk of daily practice in a busy imaging department. Radiologists are required to be familiar with the instrumentation and operative options used in spinal fixation and fusion procedures, especially in his or her institute. This is critical in evaluating the position of implants and potential complications associated with the operative approaches and spinal fixation devices used. Thus, the radiologist can play an important role in patient care and outcome. This review outlines the advantages and disadvantages of commonly used imaging methods and reports on the best yield for each modality and how to overcome the problematic issues associated with the presence of metallic hardware during imaging. Baseline radiographs are essential as they are the baseline point for evaluation of future studies should patients develop symptoms suggesting possible complications. They may justify further imaging workup with computed tomography, magnetic resonance and/or nuclear medicine studies as the evaluation of a patient with a spinal implant involves a multi-modality approach. This review describes imaging features of potential complications associated with spinal fusion surgery as well as the instrumentation used. This basic knowledge aims to help radiologists approach everyday practice in clinical imaging. PMID:22761979

  18. Spectral edge: gradient-preserving spectral mapping for image fusion.

    Science.gov (United States)

    Connah, David; Drew, Mark S; Finlayson, Graham D

    2015-12-01

    This paper describes a novel approach to image fusion for color display. Our goal is to generate an output image whose gradient matches that of the input as closely as possible. We achieve this using a constrained contrast mapping paradigm in the gradient domain, where the structure tensor of a high-dimensional gradient representation is mapped exactly to that of a low-dimensional gradient field which is then reintegrated to form an output. Constraints on output colors are provided by an initial RGB rendering. Initially, we motivate our solution with a simple "ansatz" (educated guess) for projecting higher-D contrast onto color gradients, which we expand to a more rigorous theorem to incorporate color constraints. The solution to these constrained optimizations is closed-form, allowing for simple and hence fast and efficient algorithms. The approach can map any N-D image data to any M-D output and can be used in a variety of applications using the same basic algorithm. In this paper, we focus on the problem of mapping N-D inputs to 3D color outputs. We present results in five applications: hyperspectral remote sensing, fusion of color and near-infrared or clear-filter images, multilighting imaging, dark flash, and color visualization of magnetic resonance imaging diffusion-tensor imaging.

  19. Clinical evaluation of bone-subtraction CT angiography (BSCTA) in head and neck imaging

    International Nuclear Information System (INIS)

    Lell, M.; Anders, K.; Bautz, W.; Klotz, E.; Ditt, H.; Tomandl, B.F.

    2006-01-01

    Fifty-one patients were examined with bone subtraction CT angiography (BSCTA). Data were acquired on 4-and 64-slice spiral CT systems. The post-processing method is based on fully automatic registration of non-enhanced and contrast-enhanced CT data and subsequent selective bone removal. Vascular structures and brain tissue are retained with the original CTA noise level. Image quality and delineation of the pathologic process were assessed and artifacts introduced by the bone removal process recorded. The bone subtraction algorithm worked successfully in all examinations. The processing time was 6 min on average. Image quality was rated excellent in 20 (39%), good in 26 (51%) and acceptable in 5 (10%) patients. Ophthalmic arteries were visible in 12 (24%) patients bilaterally, in 13 (25%) patients unilaterally and in 26 (51%) patients at least at the origin. BSCTA improved visualization of the infraclinoid ICA and the vertebral arteries. The depiction of stenosis of the extracranial ICA and supraclinoid aneurysms was not significantly improved. In patients with suspicion of sinus thrombosis, BSCTA and conventional CTA yielded similar results. To conclude, BSCTA improves the visualization of vessels with close contact to bone and can improve the diagnostic accuracy and therapy planning of infraclinoid aneurysms. (orig.)

  20. En Face Optical Coherence Tomography Angiography Imaging Versus Fundus Photography in the Measurement of Choroidal Nevi.

    Science.gov (United States)

    Lee, Michele D; Kaidonis, Georgia; Kim, Alice Y; Shields, Ryan A; Leng, Theodore

    2017-09-01

    Choroidal nevi are common benign intraocular tumors with a small risk of malignant transformation. This retrospective study investigates the use of en face spectral-domain optical coherence tomography angiography (SD-OCTA) in determining the clinical features and measurement of choroidal nevi. Patients with choroidal nevi were imaged with both OCTA and a fundus photography device. Greatest longitudinal dimension (GLD), perpendicular dimension (PD), and the GLD/PD ratio were assessed on each device. Inter-device variation and intra- and inter-rater reliability analyses were performed. Fourteen patients with choroidal nevi were included. No significant difference between the GLD/PD ratio as measured by all three devices was found (Chi-square = 2.8, 2 df, P = .247). Intraclass correlation coefficients were greater than 0.7 for repeated measures on all devices, suggesting good repeatability and reproducibility. This study demonstrated inter-device consistency and high intra- and inter-rater reliability when measuring choroidal nevi. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:741-747.]. Copyright 2017, SLACK Incorporated.

  1. Technical feasibility and validation of a coronary artery calcium scoring system using CT coronary angiography images

    Energy Technology Data Exchange (ETDEWEB)

    Pavitt, Christopher W. [Royal Brompton Hospital, Department of Cardiology, London (United Kingdom); Royal Brompton Hospital, Department of Radiology, London (United Kingdom); Harron, Katie [Institute of Child Health, UCL, Centre for Paediatric Epidemiology and Biostatistics, London (United Kingdom); Lindsay, Alistair C.; Ray, Robin [Royal Brompton Hospital, Department of Cardiology, London (United Kingdom); Zielke, Sayeh; Rubens, Michael B. [Royal Brompton Hospital, Department of Radiology, London (United Kingdom); Gordon, Daniel [Royal Marsden Hospital, Department of Physics, London (United Kingdom); Padley, Simon P. [Royal Brompton Hospital, Department of Radiology, London (United Kingdom); Imperial College, Faculty of Medicine, London (United Kingdom); Nicol, Edward D. [Royal Brompton Hospital, Department of Cardiology, London (United Kingdom); Royal Brompton Hospital, Department of Radiology, London (United Kingdom); Imperial College, Faculty of Medicine, London (United Kingdom)

    2016-05-15

    We validate a novel CT coronary angiography (CCTA) coronary calcium scoring system. Calcium was quantified on CCTA images using a new patient-specific attenuation threshold: mean + 2SD of intra-coronary contrast density (HU). Using 335 patient data sets a conversion factor (CF) for predicting CACS from CCTA scores (CCTAS) was derived and validated in a separate cohort (n = 168). Bland-Altman analysis and weighted kappa for MESA centiles and Agatston risk groupings were calculated. Multivariable linear regression yielded a CF: CACS = (1.185 x CCTAS) + (0.002 x CCTAS x attenuation threshold). When applied to CCTA data sets there was excellent correlation (r = 0.95; p < 0.0001) and agreement (mean difference -10.4 [95 % limits of agreement -258.9 to 238.1]) with traditional calcium scores. Agreement was better for calcium scores below 500; however, MESA percentile agreement was better for high risk patients. Risk stratification was excellent (Agatston groups k = 0.88 and MESA centiles k = 0.91). Eliminating the dedicated CACS scan decreased patient radiation exposure by approximately one-third. CCTA calcium scores can accurately predict CACS using a simple, individualized, semiautomated approach reducing acquisition time and radiation exposure when evaluating patients for CAD. This method is not affected by the ROI location, imaging protocol, or tube voltage strengthening its clinical applicability. (orig.)

  2. Benign familial fleck retina: multimodal imaging including optical coherence tomography angiography.

    Science.gov (United States)

    Garcia, Jose Mauricio Botto de Barros; Isaac, David Leonardo Cruvinel; Sardeiro, Tainara; Aquino, Érika; Avila, Marcos

    2017-01-01

    This report presents multimodal imaging of a 27-year-old woman diagnosed with benign familial fleck retina (OMIM 228980), an uncommon disorder. Fundus photographs revealed retinal flecks that affected her post-equatorial retina but spared the macular area. Fundus autofluorescence and infrared imaging demonstrated a symmetrical pattern of yellow-white fleck lesions that affected both eyes. Her full-field electroretinogram and electrooculogram were normal. An optical coherence tomography B-scan was performed for both eyes, revealing increased thickness of the retinal pigmented epithelium leading to multiple small pigmented epithelium detachments. The outer retina remained intact in both eyes. Spectral-domain optical coherence tomography angiography with split-spectrum amplitude decorrelation algorithm and 3 × 3 mm structural en face optical coherence tomography did not show macular lesions. Benign familial fleck retina belongs to a heterogenous group of so-called flecked retina syndromes, and should be considered in patients with yellowish-white retinal lesions without involvement of the macula.

  3. Benign familial fleck retina: multimodal imaging including optical coherence tomography angiography

    Directory of Open Access Journals (Sweden)

    Jose Mauricio Botto de Barros Garcia

    Full Text Available ABSTRACT This report presents multimodal imaging of a 27-year-old woman diagnosed with benign familial fleck retina (OMIM 228980, an uncommon disorder. Fundus photographs revealed retinal flecks that affected her post-equatorial retina but spared the macular area. Fundus autofluorescence and infrared imaging demonstrated a symmetrical pattern of yellow-white fleck lesions that affected both eyes. Her full-field electroretinogram and electrooculogram were normal. An optical coherence tomography B-scan was performed for both eyes, revealing increased thickness of the retinal pigmented epithelium leading to multiple small pigmented epithelium detachments. The outer retina remained intact in both eyes. Spectral-domain optical coherence tomography angiography with split-spectrum amplitude decorrelation algorithm and 3 × 3 mm structural en face optical coherence tomography did not show macular lesions. Benign familial fleck retina belongs to a heterogenous group of so-called flecked retina syndromes, and should be considered in patients with yellowish-white retinal lesions without involvement of the macula.

  4. Self-assessed performance improves statistical fusion of image labels

    International Nuclear Information System (INIS)

    Bryan, Frederick W.; Xu, Zhoubing; Asman, Andrew J.; Allen, Wade M.; Reich, Daniel S.; Landman, Bennett A.

    2014-01-01

    Purpose: Expert manual labeling is the gold standard for image segmentation, but this process is difficult, time-consuming, and prone to inter-individual differences. While fully automated methods have successfully targeted many anatomies, automated methods have not yet been developed for numerous essential structures (e.g., the internal structure of the spinal cord as seen on magnetic resonance imaging). Collaborative labeling is a new paradigm that offers a robust alternative that may realize both the throughput of automation and the guidance of experts. Yet, distributing manual labeling expertise across individuals and sites introduces potential human factors concerns (e.g., training, software usability) and statistical considerations (e.g., fusion of information, assessment of confidence, bias) that must be further explored. During the labeling process, it is simple to ask raters to self-assess the confidence of their labels, but this is rarely done and has not been previously quantitatively studied. Herein, the authors explore the utility of self-assessment in relation to automated assessment of rater performance in the context of statistical fusion. Methods: The authors conducted a study of 66 volumes manually labeled by 75 minimally trained human raters recruited from the university undergraduate population. Raters were given 15 min of training during which they were shown examples of correct segmentation, and the online segmentation tool was demonstrated. The volumes were labeled 2D slice-wise, and the slices were unordered. A self-assessed quality metric was produced by raters for each slice by marking a confidence bar superimposed on the slice. Volumes produced by both voting and statistical fusion algorithms were compared against a set of expert segmentations of the same volumes. Results: Labels for 8825 distinct slices were obtained. Simple majority voting resulted in statistically poorer performance than voting weighted by self-assessed performance

  5. Self-assessed performance improves statistical fusion of image labels

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Frederick W., E-mail: frederick.w.bryan@vanderbilt.edu; Xu, Zhoubing; Asman, Andrew J.; Allen, Wade M. [Electrical Engineering, Vanderbilt University, Nashville, Tennessee 37235 (United States); Reich, Daniel S. [Translational Neuroradiology Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892 (United States); Landman, Bennett A. [Electrical Engineering, Vanderbilt University, Nashville, Tennessee 37235 (United States); Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37235 (United States); and Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee 37235 (United States)

    2014-03-15

    Purpose: Expert manual labeling is the gold standard for image segmentation, but this process is difficult, time-consuming, and prone to inter-individual differences. While fully automated methods have successfully targeted many anatomies, automated methods have not yet been developed for numerous essential structures (e.g., the internal structure of the spinal cord as seen on magnetic resonance imaging). Collaborative labeling is a new paradigm that offers a robust alternative that may realize both the throughput of automation and the guidance of experts. Yet, distributing manual labeling expertise across individuals and sites introduces potential human factors concerns (e.g., training, software usability) and statistical considerations (e.g., fusion of information, assessment of confidence, bias) that must be further explored. During the labeling process, it is simple to ask raters to self-assess the confidence of their labels, but this is rarely done and has not been previously quantitatively studied. Herein, the authors explore the utility of self-assessment in relation to automated assessment of rater performance in the context of statistical fusion. Methods: The authors conducted a study of 66 volumes manually labeled by 75 minimally trained human raters recruited from the university undergraduate population. Raters were given 15 min of training during which they were shown examples of correct segmentation, and the online segmentation tool was demonstrated. The volumes were labeled 2D slice-wise, and the slices were unordered. A self-assessed quality metric was produced by raters for each slice by marking a confidence bar superimposed on the slice. Volumes produced by both voting and statistical fusion algorithms were compared against a set of expert segmentations of the same volumes. Results: Labels for 8825 distinct slices were obtained. Simple majority voting resulted in statistically poorer performance than voting weighted by self-assessed performance

  6. Intra-Arterial MR Perfusion Imaging of Meningiomas: Comparison to Digital Subtraction Angiography and Intravenous MR Perfusion Imaging.

    Directory of Open Access Journals (Sweden)

    Mark A Lum

    Full Text Available To evaluate the ability of IA MR perfusion to characterize meningioma blood supply.Studies were performed in a suite comprised of an x-ray angiography unit and 1.5T MR scanner that permitted intraprocedural patient movement between the imaging modalities. Patients underwent intra-arterial (IA and intravenous (IV T2* dynamic susceptibility MR perfusion immediately prior to meningioma embolization. Regional tumor arterial supply was characterized by digital subtraction angiography and classified as external carotid artery (ECA dural, internal carotid artery (ICA dural, or pial. MR perfusion data regions of interest (ROIs were analyzed in regions with different vascular supply to extract peak height, full-width at half-maximum (FWHM, relative cerebral blood flow (rCBF, relative cerebral blood volume (rCBV, and mean transit time (MTT. Linear mixed modeling was used to identify perfusion curve parameter differences for each ROI for IA and IV MR imaging techniques. IA vs. IV perfusion parameters were also directly compared for each ROI using linear mixed modeling.18 ROIs were analyzed in 12 patients. Arterial supply was identified as ECA dural (n = 11, ICA dural (n = 4, or pial (n = 3. FWHM, rCBV, and rCBF showed statistically significant differences between ROIs for IA MR perfusion. Peak Height and FWHM showed statistically significant differences between ROIs for IV MR perfusion. RCBV and MTT were significantly lower for IA perfusion in the Dural ECA compared to IV perfusion. Relative CBF in IA MR was found to be significantly higher in the Dural ICA region and MTT significantly lower compared to IV perfusion.

  7. Compact imaging Bragg spectrometer for fusion devices

    International Nuclear Information System (INIS)

    Bertschinger, G.; Biel, W.; Jaegers, H.; Marchuk, O.

    2004-01-01

    A compact imaging x-ray spectrometer has been designed for tokamaks and stellarators to measure the plasma parameters at different spatial chords. It has been optimized for high spectral resolution and high sensitivity. High spectral resolution is obtained by using solid state detectors and minimizing the imaging errors of the spherical crystals. It is shown, that using spherical crystals the solid angle and hence the throughput can be increased significantly, without compromising the spectral resolution. The design is useful for the measurement of the spectra of He- and H-like ions from Si to Kr. The spectral resolution is sufficient for the measurement of plasma parameters. The temporal resolution is high enough for transport studies by gas puff and laser ablation experiments. The design is based on a modified Johann spectrometer mount, utilizing a spherically bent crystal instead of the cylindrically bent crystal in the traditional Johann mount. The astigmatism of the wavelength selective reflection on the spherical crystal is applied to obtain imaging of an extended plasma source on a two-dimensional detector. For each element, a separate crystal is required, only in few cases, a crystal can be used for the spectra of two elements. For the spectra of most of the He-like ions from Si up to Kr, suitable crystal cuts have been found on quartz, silicon and germanium crystals with Bragg angles in a small interval around the design value of 53.5 deg. All of the crystals have the same radius. They are fixed on a rotational table. The distance to the detector is adjusted by an x-y table to fit to the Rowland circle

  8. An efficient multiple exposure image fusion in JPEG domain

    Science.gov (United States)

    Hebbalaguppe, Ramya; Kakarala, Ramakrishna

    2012-01-01

    In this paper, we describe a method to fuse multiple images taken with varying exposure times in the JPEG domain. The proposed algorithm finds its application in HDR image acquisition and image stabilization for hand-held devices like mobile phones, music players with cameras, digital cameras etc. Image acquisition at low light typically results in blurry and noisy images for hand-held camera's. Altering camera settings like ISO sensitivity, exposure times and aperture for low light image capture results in noise amplification, motion blur and reduction of depth-of-field respectively. The purpose of fusing multiple exposures is to combine the sharp details of the shorter exposure images with high signal-to-noise-ratio (SNR) of the longer exposure images. The algorithm requires only a single pass over all images, making it efficient. It comprises of - sigmoidal boosting of shorter exposed images, image fusion, artifact removal and saturation detection. Algorithm does not need more memory than a single JPEG macro block to be kept in memory making it feasible to be implemented as the part of a digital cameras hardware image processing engine. The Artifact removal step reuses the JPEGs built-in frequency analysis and hence benefits from the considerable optimization and design experience that is available for JPEG.

  9. Development and application of PET-MRI image fusion technology

    International Nuclear Information System (INIS)

    Song Jianhua; Zhao Jinhua; Qiao Wenli

    2011-01-01

    The emerging and growing in popularity of PET-CT scanner brings us the convenience and cognizes the advantages such as diagnosis, staging, curative effect evaluation and prognosis for malignant tumor. And the PET-MRI installing maybe a new upsurge when the machine gradually mature, because of the MRI examination without the radiation exposure and with the higher soft tissue resolution. This paper summarized the developing course of image fusion technology and some researches of clinical application about PET-MRI at present, in order to help people to understand the functions and know its wide application of the upcoming new instrument, mainly focuses the application on the central nervous system and some soft tissue lesions. And before PET-MRI popularization, people can still carry out some researches of various image fusion and clinical application on the current equipment. (authors)

  10. Study on Efficiency of Fusion Techniques for IKONOS Images

    International Nuclear Information System (INIS)

    Liu, Yanmei; Yu, Haiyang; Guijun, Yang; Nie, Chenwei; Yang, Xiaodong; Ren, Dong

    2014-01-01

    Many image fusion techniques have been proposed to achieve optimal resolution in the spatial and spectral domains. Six different merging methods were listed in this paper and the efficiency of fusion techniques was assessed in qualitative and quantitative aspect. Both local and global evaluation parameters were used in the spectral quality and a Laplace filter method was used in spatial quality assessment. By simulation, the spectral quality of the images merged by Brovery was demonstrated to be the worst. In contrast, GS and PCA algorithms, especially the Pansharpening provided higher spectral quality than the standard Brovery, wavelet and CN methods. In spatial quality assessment, the CN method represented best compared with that of others, while the Brovery algorithm was worst. The wavelet parameters that performed best achieved acceptable spectral and spatial quality compared to the others

  11. Fourier domain image fusion for differential X-ray phase-contrast breast imaging

    International Nuclear Information System (INIS)

    Coello, Eduardo; Sperl, Jonathan I.; Bequé, Dirk; Benz, Tobias; Scherer, Kai; Herzen, Julia; Sztrókay-Gaul, Anikó; Hellerhoff, Karin; Pfeiffer, Franz; Cozzini, Cristina; Grandl, Susanne

    2017-01-01

    X-Ray Phase-Contrast (XPC) imaging is a novel technology with a great potential for applications in clinical practice, with breast imaging being of special interest. This work introduces an intuitive methodology to combine and visualize relevant diagnostic features, present in the X-ray attenuation, phase shift and scattering information retrieved in XPC imaging, using a Fourier domain fusion algorithm. The method allows to present complementary information from the three acquired signals in one single image, minimizing the noise component and maintaining visual similarity to a conventional X-ray image, but with noticeable enhancement in diagnostic features, details and resolution. Radiologists experienced in mammography applied the image fusion method to XPC measurements of mastectomy samples and evaluated the feature content of each input and the fused image. This assessment validated that the combination of all the relevant diagnostic features, contained in the XPC images, was present in the fused image as well.

  12. Fourier domain image fusion for differential X-ray phase-contrast breast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Coello, Eduardo, E-mail: eduardo.coello@tum.de [GE Global Research, Garching (Germany); Lehrstuhl für Informatikanwendungen in der Medizin & Augmented Reality, Institut für Informatik, Technische Universität München, Garching (Germany); Sperl, Jonathan I.; Bequé, Dirk [GE Global Research, Garching (Germany); Benz, Tobias [Lehrstuhl für Informatikanwendungen in der Medizin & Augmented Reality, Institut für Informatik, Technische Universität München, Garching (Germany); Scherer, Kai; Herzen, Julia [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching (Germany); Sztrókay-Gaul, Anikó; Hellerhoff, Karin [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich (Germany); Pfeiffer, Franz [Lehrstuhl für Biomedizinische Physik, Physik-Department & Institut für Medizintechnik, Technische Universität München, Garching (Germany); Cozzini, Cristina [GE Global Research, Garching (Germany); Grandl, Susanne [Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich (Germany)

    2017-04-15

    X-Ray Phase-Contrast (XPC) imaging is a novel technology with a great potential for applications in clinical practice, with breast imaging being of special interest. This work introduces an intuitive methodology to combine and visualize relevant diagnostic features, present in the X-ray attenuation, phase shift and scattering information retrieved in XPC imaging, using a Fourier domain fusion algorithm. The method allows to present complementary information from the three acquired signals in one single image, minimizing the noise component and maintaining visual similarity to a conventional X-ray image, but with noticeable enhancement in diagnostic features, details and resolution. Radiologists experienced in mammography applied the image fusion method to XPC measurements of mastectomy samples and evaluated the feature content of each input and the fused image. This assessment validated that the combination of all the relevant diagnostic features, contained in the XPC images, was present in the fused image as well.

  13. Multi-Modality Registration And Fusion Of Medical Image Data

    International Nuclear Information System (INIS)

    Kassak, P.; Vencko, D.; Cerovsky, I.

    2008-01-01

    Digitalisation of health care providing facilities allows US to maximize the usage of digital data from one patient obtained by various modalities. Complex view on to the problem can be achieved from the site of morphology as well as functionality. Multi-modal registration and fusion of medical image data is one of the examples that provides improved insight and allows more precise approach and treatment. (author)

  14. Abdominal MR angiography

    International Nuclear Information System (INIS)

    Wegmueller, H.; Vock, P.

    1993-01-01

    The two techniques currently most often used for MR angiography, those based on time-of-flight effects and on phase-contrast, are introduced, and our results with three-dimensional phase contrast angiography of the abdomen are presented. Several basic differences from other imaging procedures render MR angiography clinically useful for screening for renal artery stenosis in critical situations, such as renal failure or intolerance to contrast agents. In the future, the spectrum of applications of MR angiography will broaden and include other indications, such as portal venous hypertension and follow-up studies after surgical portal systemic shunting. (orig.) [de

  15. Magnetic resonance angiography (MRA)

    International Nuclear Information System (INIS)

    Arlart, I.P.; Guhl, L.

    1992-01-01

    An account is given in this paper of the physical and technical principles underlying the 'time-of-flight' technique for imaging of vessels by magnetic resonance tomography. Major indications for the new procedure of magnetic resonance angiography at present are intracerebral and extracerebral vessels, with digital subtraction angiography quite often being required to cope with minor alterations (small aneurysms, small occlusions). Magnetic resonance angiography and digital subtraction angiography are compared to each other for advantages and disadvantages. Basically, replacement of radiological angiography by magnetic resonance angiography appears to be possible only within limits, since X-ray diagnostics primarily provides morphological information about vessels, whereas flow dynamics is visualized by the 'time-of-flight' technique. (orig.) [de

  16. Image averaging for angiography by registration and combination of serial images

    International Nuclear Information System (INIS)

    Brooks, S.H.; Selzer, R.H.; Crawford, D.W.; Blankenhorn, D.H.

    1982-01-01

    In order to increase the contrast of x-ray images of artery edges, a method is disclosed whereby a contrast medium opaque to x-rays in injected into a blood vessel distant from an artery section of interest. Mulitple x-ray images are obtained as the contrast medium and blood mixture flows through the artery section. These images are registered with a landmark within the patient. Density measurements are made with respect to each corresponding image segment and are combined to synthesize a composite image of the edge of the artery section

  17. Diagnostic performance of combined noninvasive coronary angiography and myocardial perfusion imaging using 320 row detector computed tomography

    DEFF Research Database (Denmark)

    Vavere, Andrea L; Simon, Gregory G; George, Richard T

    2013-01-01

    Multidetector coronary computed tomography angiography (CTA) is a promising modality for widespread clinical application because of its noninvasive nature and high diagnostic accuracy as found in previous studies using 64 to 320 simultaneous detector rows. It is, however, limited in its ability...... to detect myocardial ischemia. In this article, we describe the design of the CORE320 study ("Combined coronary atherosclerosis and myocardial perfusion evaluation using 320 detector row computed tomography"). This prospective, multicenter, multinational study is unique in that it is designed to assess...... the diagnostic performance of combined 320-row CTA and myocardial CT perfusion imaging (CTP) in comparison with the combination of invasive coronary angiography and single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). The trial is being performed at 16 medical centers located in 8...

  18. Enabling image fusion for a CT guided needle placement robot

    Science.gov (United States)

    Seifabadi, Reza; Xu, Sheng; Aalamifar, Fereshteh; Velusamy, Gnanasekar; Puhazhendi, Kaliyappan; Wood, Bradford J.

    2017-03-01

    Purpose: This study presents development and integration of hardware and software that enables ultrasound (US) and computer tomography (CT) fusion for a FDA-approved CT-guided needle placement robot. Having real-time US image registered to a priori-taken intraoperative CT image provides more anatomic information during needle insertion, in order to target hard-to-see lesions or avoid critical structures invisible to CT, track target motion, and to better monitor ablation treatment zone in relation to the tumor location. Method: A passive encoded mechanical arm is developed for the robot in order to hold and track an abdominal US transducer. This 4 degrees of freedom (DOF) arm is designed to attach to the robot end-effector. The arm is locked by default and is released by a press of button. The arm is designed such that the needle is always in plane with US image. The articulated arm is calibrated to improve its accuracy. Custom designed software (OncoNav, NIH) was developed to fuse real-time US image to a priori-taken CT. Results: The accuracy of the end effector before and after passive arm calibration was 7.07mm +/- 4.14mm and 1.74mm +/-1.60mm, respectively. The accuracy of the US image to the arm calibration was 5mm. The feasibility of US-CT fusion using the proposed hardware and software was demonstrated in an abdominal commercial phantom. Conclusions: Calibration significantly improved the accuracy of the arm in US image tracking. Fusion of US to CT using the proposed hardware and software was feasible.

  19. Spatial, Temporal and Spectral Satellite Image Fusion via Sparse Representation

    Science.gov (United States)

    Song, Huihui

    Remote sensing provides good measurements for monitoring and further analyzing the climate change, dynamics of ecosystem, and human activities in global or regional scales. Over the past two decades, the number of launched satellite sensors has been increasing with the development of aerospace technologies and the growing requirements on remote sensing data in a vast amount of application fields. However, a key technological challenge confronting these sensors is that they tradeoff between spatial resolution and other properties, including temporal resolution, spectral resolution, swath width, etc., due to the limitations of hardware technology and budget constraints. To increase the spatial resolution of data with other good properties, one possible cost-effective solution is to explore data integration methods that can fuse multi-resolution data from multiple sensors, thereby enhancing the application capabilities of available remote sensing data. In this thesis, we propose to fuse the spatial resolution with temporal resolution and spectral resolution, respectively, based on sparse representation theory. Taking the study case of Landsat ETM+ (with spatial resolution of 30m and temporal resolution of 16 days) and MODIS (with spatial resolution of 250m ~ 1km and daily temporal resolution) reflectance, we propose two spatial-temporal fusion methods to combine the fine spatial information of Landsat image and the daily temporal resolution of MODIS image. Motivated by that the images from these two sensors are comparable on corresponding bands, we propose to link their spatial information on available Landsat- MODIS image pair (captured on prior date) and then predict the Landsat image from the MODIS counterpart on prediction date. To well-learn the spatial details from the prior images, we use a redundant dictionary to extract the basic representation atoms for both Landsat and MODIS images based on sparse representation. Under the scenario of two prior Landsat

  20. Dual energy CT intracranial angiography: image quality, radiation dose and initial application results

    International Nuclear Information System (INIS)

    Chai Xue; Zhang Longjiang; Lu Guangming; Zhou Changsheng

    2009-01-01

    Objective: To assess the clinical value of dual-energy intracranial CT angiography (CTA). Methods: Forty-one patients suspected of intracranial vascular diseases underwent dual-energy intracranial CT angiography, and 41 patients who underwent conventional subtraction CT were enrolled as the control group. Image quality of intracranial and skull base vessels and radiation dose between dual-energy CTA and conventional subtraction CTA were compared using two independent sample nonparametric test and independent-samples t test, respectively. Prevalence and size of lesions detected by dual-energy CTA and digital subtraction CTA were compared using paired-samples t test and Spearman correlative analysis. Results: The percentage of image quality scored 5 was 70.7% (29/41) for dual-energy CTA and 75.6% (31/41) for conventional subtraction CTA. There was no significant difference between the two groups (Z= -0.455, P=0.650). Image quality of vessels at the skull base in conventional subtraction CTA was superior to that in dual-energy CTA, especially for the petrosal and syphon segment (Z=-4.087, P=0.000). Radiation exposure of dual energy CTA and conventional CTA were (396.54±17.43) and (1090.95±114.29) mGy·cm respectively. Radiation exposure was decreased by 64% (t=-38.52, P=0.000) by dual energy CTA compared with conventional subtraction CTA. Out of the 41 patients, 19 patients were diagnosed as intracranial aneurysm, 2 patients as arteriovenous malformation (AVM), 3 patients with Moya-moya's disease, and the remaining 17 patients with negative results. Nine patients with intracranial aneurysm, 2 patients with AVM, 3 patients with Moya-moya's disease, and 2 patients with negative findings underwent DSA or operation, with concordant findings from both techniques. Diameter of aneurysm neck, long axis and minor axis by dual-energy CTA was (2.90±1.61), (5.23±1.68) and (3.83±1.69) mm, respectively; Diameter of aneurysm neck, long axis and minor axis by DSA was (2.95±1

  1. Chronic hepatosplenic schistosomiasis mansoni: magnetic resonance imaging and magnetic resonance angiography findings

    International Nuclear Information System (INIS)

    Bezerra, A.S.; D'Ippolito, G.; Caldana, R.P.; Cecin, A.O.; Ahmed, M.; Szejnfeld, J.

    2007-01-01

    Purpose: To evaluate the hepatosplenic manifestations and the portal venous system in patients with chronic infection by Schistosoma mansoni. Material and Methods: A cross-sectional observational study was performed in 28 patients with chronic hepatosplenic schistosomiasis submitted to magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the abdomen. Images were interpreted independently by two radiologists to determine the reproducibility of image interpretation and who evaluated the presence of morphological alterations in the liver and spleen, such as hepatosplenomegaly, hepatic fissure widening, periportal fibrosis, and the presence of siderotic nodules. Interobserver and intra-observer agreement were measured with the kappa and intraclass correlation tests. Evaluation of venous collateral pathways and portal and splenic veins was done in consensus by both examiners. Results: Observers identified enlargement of the left lobe (78.5-92.8%) and caudate-to-right-lobe ratio (78.5-92.8%), irregularity of hepatic contours (89.2-96.4%), fissure widening (89.2-100%), and splenic siderotic nodules (84.2%). Splenomegaly, heterogeneity of hepatic parenchyma, peripheral hepatic vessels, and periportal fibrosis were observed in 100% of patients. MRI findings presented almost perfect interobserver (kappa 0.65-1) and intra-observer (kappa = 0.73-1 for observer 1, and kappa = 0.65-1 for observer 2) agreement for the variables analyzed. MRA showed the presence of collateral pathways in the majority of patients (71.4%) along with widening of portal and splenic veins. Conclusion: Using MRI, hepatosplenic alterations in schistosomiasis are characterized by heterogeneity of hepatic parenchyma, presence of peripheral perihepatic vessels, periportal fibrosis, splenomegaly, siderotic nodules, and the presence of venous collateral pathways

  2. Image quality on dual-source computed-tomographic coronary angiography

    International Nuclear Information System (INIS)

    Rixe, Johannes; Rolf, Andreas; Conradi, Guido; Elsaesser, Albrecht; Moellmann, Helge; Nef, Holger M.; Hamm, Christian W.; Dill, Thorsten; Bachmann, Georg

    2008-01-01

    Multi-detector CT reliably permits visualization of coronary arteries, but due to the occurrence of motion artefacts at heart rates >65 bpm caused by a temporal resolution of 165 ms, its utilisation has so far been limited to patients with a preferably low heart rate. We investigated the assessment of image quality on computed tomography of coronary arteries in a large series of patients without additional heart rate control using dual-source computed tomography (DSCT). DSCT (Siemens Somatom Definition, 83-ms temporal resolution) was performed in 165 consecutive patients (mean age 64±11.4 years) after injection of 60-80 ml of contrast. Data sets were reconstructed in 5% intervals of the cardiac cycle and evaluated by two readers in consensus concerning evaluability of the coronary arteries and presence of motion and beam-hardening artefacts using the AHA 16-segment coronary model. Mean heart rate during CT was 65±10.5 bpm; visualisation without artefacts was possible in 98.7% of 2,541 coronary segments. Only two segments were considered unevaluable due to cardiac motion; 30 segments were unassessable due to poor signal-to-noise ratio or coronary calcifications (both n=15). Data reconstruction at 65-70% of the cardiac cycle provided for the best image quality. For heart rates >85 bpm, a systolic reconstruction at 45% revealed satisfactory results. Compared with earlier CT generations, DSCT provides for non-invasive coronary angiography with diagnostic image quality even at heart rates >65 bpm and thus may broaden the spectrum of patients that can be investigated non-invasively. (orig.)

  3. T2*-weighted image/T2-weighted image fusion in postimplant dosimetry of prostate brachytherapy

    International Nuclear Information System (INIS)

    Katayama, Norihisa; Takemoto, Mitsuhiro; Yoshio, Kotaro

    2011-01-01

    Computed tomography (CT)/magnetic resonance imaging (MRI) fusion is considered to be the best method for postimplant dosimetry of permanent prostate brachytherapy; however, it is inconvenient and costly. In T2 * -weighted image (T2 * -WI), seeds can be easily detected without the use of an intravenous contrast material. We present a novel method for postimplant dosimetry using T2 * -WI/T2-weighted image (T2-WI) fusion. We compared the outcomes of T2 * -WI/T2-WI fusion-based and CT/T2-WI fusion-based postimplant dosimetry. Between April 2008 and July 2009, 50 consecutive prostate cancer patients underwent brachytherapy. All the patients were treated with 144 Gy of brachytherapy alone. Dose-volume histogram (DVH) parameters (prostate D90, prostate V100, prostate V150, urethral D10, and rectal D2cc) were prospectively compared between T2 * -WI/T2-WI fusion-based and CT/T2-WI fusion-based dosimetry. All the DVH parameters estimated by T2 * -WI/T2-WI fusion-based dosimetry strongly correlated to those estimated by CT/T2-WI fusion-based dosimetry (0.77≤ R ≤0.91). No significant difference was observed in these parameters between the two methods, except for prostate V150 (p=0.04). These results show that T2 * -WI/T2-WI fusion-based dosimetry is comparable or superior to MRI-based dosimetry as previously reported, because no intravenous contrast material is required. For some patients, rather large differences were observed in the value between the 2 methods. We thought these large differences were a result of seed miscounts in T2 * -WI and shifts in fusion. Improving the image quality of T2 * -WI and the image acquisition speed of T2 * -WI and T2-WI may decrease seed miscounts and fusion shifts. Therefore, in the future, T2 * -WI/T2-WI fusion may be more useful for postimplant dosimetry of prostate brachytherapy. (author)

  4. Improving Accuracy for Image Fusion in Abdominal Ultrasonography

    Directory of Open Access Journals (Sweden)

    Caroline Ewertsen

    2012-08-01

    Full Text Available Image fusion involving real-time ultrasound (US is a technique where previously recorded computed tomography (CT or magnetic resonance images (MRI are reformatted in a projection to fit the real-time US images after an initial co-registration. The co-registration aligns the images by means of common planes or points. We evaluated the accuracy of the alignment when varying parameters as patient position, respiratory phase and distance from the co-registration points/planes. We performed a total of 80 co-registrations and obtained the highest accuracy when the respiratory phase for the co-registration procedure was the same as when the CT or MRI was obtained. Furthermore, choosing co-registration points/planes close to the area of interest also improved the accuracy. With all settings optimized a mean error of 3.2 mm was obtained. We conclude that image fusion involving real-time US is an accurate method for abdominal examinations and that the accuracy is influenced by various adjustable factors that should be kept in mind.

  5. Comparison of 3D magnetic resonance imaging and digital subtraction angiography for intracranial artery stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Eun; Jung, Seung Chai; Kim, Ho Sung; Choi, Choong-Gon; Kim, Sang Joon; Lee, Deok Hee [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of); Lee, Sang Hun; Kwon, Sun U.; Kang, Dong-Wha; Kim, Jong S. [University of Ulsan College of Medicine, Department of Neurology, Ulsan (Korea, Republic of); Jeon, Ji Young [Gachon University, Department of Radiology, Gil Medical Center, Incheon (Korea, Republic of); Lee, Ji Ye [Soonchunhyang University Bucheon Hospital, Department of Radiology, Bucheon (Korea, Republic of); Kim, Seon-Ok [University of Ulsan College of Medicine, Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, Seoul (Korea, Republic of)

    2017-11-15

    To compare three-dimensional high-resolution magnetic resonance imaging (3D HR-MRI) and digital subtraction angiography (DSA) for diagnosing and evaluating stenosis in the entire circle of Willis. The study included 516 intracranial arteries from 43 patients with intracranial artery stenosis (ICAS) who underwent both 3D HR-MRI and DSA within 1 month. Two readers independently diagnosed atherosclerosis, dissection, moyamoya disease and vasculitis, rated their diagnostic confidence for each vessel and measured the luminal diameters. Reference standard was made from clinico-radiologic diagnosis. Diagnostic accuracy, diagnostic confidence, the degree of stenosis and luminal diameter were assessed and compared between both modalities. For atherosclerosis, 3D HR-MRI showed better diagnostic accuracy (P =.03-.003), sensitivity (P =.006-.01) and positive predictive value (P ≤.001-.006) compared to DSA. Overall, the readers were more confident of their diagnosis of ICAS when using 3D HR-MRI (reader 1, P ≤.001-.007; reader 2, P ≤.001-.015). 3D HR-MRI showed similar degree of stenosis (P >.05) and higher luminal diameter (P <.05) compared to DSA. 3D HR-MRI might be useful to evaluate atherosclerosis, with better diagnostic confidence and comparable stenosis measurement compared to DSA in the entire circle of Willis. (orig.)

  6. Image fusion in x-ray differential phase-contrast imaging

    Science.gov (United States)

    Haas, W.; Polyanskaya, M.; Bayer, F.; Gödel, K.; Hofmann, H.; Rieger, J.; Ritter, A.; Weber, T.; Wucherer, L.; Durst, J.; Michel, T.; Anton, G.; Hornegger, J.

    2012-02-01

    Phase-contrast imaging is a novel modality in the field of medical X-ray imaging. The pioneer method is the grating-based interferometry which has no special requirements to the X-ray source and object size. Furthermore, it provides three different types of information of an investigated object simultaneously - absorption, differential phase-contrast and dark-field images. Differential phase-contrast and dark-field images represent a completely new information which has not yet been investigated and studied in context of medical imaging. In order to introduce phase-contrast imaging as a new modality into medical environment the resulting information about the object has to be correctly interpreted. The three output images reflect different properties of the same object the main challenge is to combine and visualize these data in such a way that it diminish the information explosion and reduce the complexity of its interpretation. This paper presents an intuitive image fusion approach which allows to operate with grating-based phase-contrast images. It combines information of the three different images and provides a single image. The approach is implemented in a fusion framework which is aimed to support physicians in study and analysis. The framework provides the user with an intuitive graphical user interface allowing to control the fusion process. The example given in this work shows the functionality of the proposed method and the great potential of phase-contrast imaging in medical practice.

  7. Research on Methods of Infrared and Color Image Fusion Based on Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Zhao Rentao

    2014-06-01

    Full Text Available There is significant difference in the imaging features of infrared image and color image, but their fusion images also have very good complementary information. In this paper, based on the characteristics of infrared image and color image, first of all, wavelet transform is applied to the luminance component of the infrared image and color image. In multi resolution the relevant regional variance is regarded as the activity measure, relevant regional variance ratio as the matching measure, and the fusion image is enhanced in the process of integration, thus getting the fused images by final synthesis module and multi-resolution inverse transform. The experimental results show that the fusion image obtained by the method proposed in this paper is better than the other methods in keeping the useful information of the original infrared image and the color information of the original color image. In addition, the fusion image has stronger adaptability and better visual effect.

  8. Evaluation of full time and half time acquired cardiac perfusion images and its correlation with coronary angiography

    International Nuclear Information System (INIS)

    Madhusudhanan, P.; Kapoor, A.; Arya, A.; Ora, M.; Kheruka, S.; Dube, V.; Uttam Kumar; Verma, R.S.; Singh, R.D.; Gambhir, S.

    2010-01-01

    Full text: The myocardial perfusion study takes a longer time to complete. A reduction in acquisition time would mean reduced patient motion related artifacts, improvement in camera efficiency and reduction in cost. Iterative reconstruction algorithms produce more accurate images with fewer artifacts. Materials and Methods: Seventy three patients undergoing myocardial perfusion imaging were selected for additional half time acquisition. Patients with suspected or known coronary artery disease who have undergone coronary angiography recently were preferably included. Images were analysed in 4 groups - full time FBP, half time FBP, half time OSEM and half time OSEM. Three independent observers blinded to the clinical data and the acquisition protocol analysed images for change in image quality between these groups. Semiquantitative parameters of summed stress score, summed rest score, summed difference score and left ventricular ejection fraction were also compared using appropriate statistical methods. Results: No difference was noted in SSS, SRS, SDS and LVEF calculated for full time and half time. However, significant difference was found between SSS, SRS and SDS calculated for FBP and OSEM processed half time studies and no significant difference for LVEF calculated for these two groups. Significant change in image quality was noted by 2 observers only in 1.4% and 2.7% of cases. A true positivity rate of 88% was seen in comparison with coronary angiography. Conclusion: Gated myocardial perfusion SPECT images acquired in half the routine scan time provides equal diagnostic information compared to a conventional full time study, regardless of the processing protocol

  9. Multiscale infrared and visible image fusion using gradient domain guided image filtering

    Science.gov (United States)

    Zhu, Jin; Jin, Weiqi; Li, Li; Han, Zhenghao; Wang, Xia

    2018-03-01

    For better surveillance with infrared and visible imaging, a novel hybrid multiscale decomposition fusion method using gradient domain guided image filtering (HMSD-GDGF) is proposed in this study. In this method, hybrid multiscale decomposition with guided image filtering and gradient domain guided image filtering of source images are first applied before the weight maps of each scale are obtained using a saliency detection technology and filtering means with three different fusion rules at different scales. The three types of fusion rules are for small-scale detail level, large-scale detail level, and base level. Finally, the target becomes more salient and can be more easily detected in the fusion result, with the detail information of the scene being fully displayed. After analyzing the experimental comparisons with state-of-the-art fusion methods, the HMSD-GDGF method has obvious advantages in fidelity of salient information (including structural similarity, brightness, and contrast), preservation of edge features, and human visual perception. Therefore, visual effects can be improved by using the proposed HMSD-GDGF method.

  10. Value of CT angiography in anterior circulation large vessel occlusive stroke: Imaging findings, pearls, and pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Power, Sarah, E-mail: drsarahpower@gmail.com [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); McEvoy, Sinead H., E-mail: sineadmcevoy@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Cunningham, Jane, E-mail: janecunningham0708@gmail.com [Department of Radiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Ti, Joanna P., E-mail: joannapearlyti@gmail.com [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Looby, Seamus, E-mail: seamuslooby@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); O' Hare, Alan, E-mail: alanohare@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Williams, David, E-mail: davidwilliams@rcsi.ie [Department of Geriatrics and Stroke Medicine, Royal College of Surgeons in Ireland (RCSI) and Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Brennan, Paul, E-mail: paulbrennan@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland); Thornton, John, E-mail: johnthornton@beaumont.ie [Department of Neuroradiology, Beaumont Hospital, P.O. Box 1297, Beaumont Rd, Dublin 9 (Ireland)

    2015-07-15

    Highlights: • Site of occlusion determines potential collateralization routes and impacts outcome. • Multifocality of arterial occlusion is common, seen in approximately 20% of cases. • ICA false occlusion sign can be seen in setting of ICA stenosis or carotid T occlusion. • False patency sign: hyperdense thrombus/calcified occlusive plaque misinterpreted as patent vessel. • Additional abnormalities on CTA may infer stroke mechanism or alter decision making. - Abstract: Hyperacute stroke imaging is playing an increasingly important role in determining management decisions in acute stroke patients, particularly patients with large vessel occlusive stroke who may benefit from endovascular intervention. CT angiography (CTA) is an important tool in the work-up of the acute stroke patient. It reliably detects large occlusive thrombi in proximal cerebral arteries and is a quick and highly accurate method in identifying candidates for endovascular stroke treatment. In this article we review the imaging findings on CTA in acute large vessel occlusive stroke using a pictorial case based approach. We retrospectively reviewed CTA studies in 48 patients presenting with acute anterior circulation large vessel occlusive stroke who were brought for intra-arterial acute stroke intervention. We discuss and illustrate patterns of proximal intracranial arterial occlusion, collateralization to the occluded territory, as well as reviewing some important pearls, pitfalls and teaching points in CTA assessment of the acute stroke patient. Performed from the level of the aortic arch CTA also gives valuable information regarding the state of other vessels in the acute stroke patient, identifying additional significant vascular stenoses or occlusions, and as we illustrate, can demonstrate other clinically significant findings which may impact on patient management and outcome.

  11. Value of CT angiography in anterior circulation large vessel occlusive stroke: Imaging findings, pearls, and pitfalls

    International Nuclear Information System (INIS)

    Power, Sarah; McEvoy, Sinead H.; Cunningham, Jane; Ti, Joanna P.; Looby, Seamus; O'Hare, Alan; Williams, David; Brennan, Paul; Thornton, John

    2015-01-01

    Highlights: • Site of occlusion determines potential collateralization routes and impacts outcome. • Multifocality of arterial occlusion is common, seen in approximately 20% of cases. • ICA false occlusion sign can be seen in setting of ICA stenosis or carotid T occlusion. • False patency sign: hyperdense thrombus/calcified occlusive plaque misinterpreted as patent vessel. • Additional abnormalities on CTA may infer stroke mechanism or alter decision making. - Abstract: Hyperacute stroke imaging is playing an increasingly important role in determining management decisions in acute stroke patients, particularly patients with large vessel occlusive stroke who may benefit from endovascular intervention. CT angiography (CTA) is an important tool in the work-up of the acute stroke patient. It reliably detects large occlusive thrombi in proximal cerebral arteries and is a quick and highly accurate method in identifying candidates for endovascular stroke treatment. In this article we review the imaging findings on CTA in acute large vessel occlusive stroke using a pictorial case based approach. We retrospectively reviewed CTA studies in 48 patients presenting with acute anterior circulation large vessel occlusive stroke who were brought for intra-arterial acute stroke intervention. We discuss and illustrate patterns of proximal intracranial arterial occlusion, collateralization to the occluded territory, as well as reviewing some important pearls, pitfalls and teaching points in CTA assessment of the acute stroke patient. Performed from the level of the aortic arch CTA also gives valuable information regarding the state of other vessels in the acute stroke patient, identifying additional significant vascular stenoses or occlusions, and as we illustrate, can demonstrate other clinically significant findings which may impact on patient management and outcome

  12. Ventilation-perfusion imaging and pulmonary angiography: changing pattern of use

    International Nuclear Information System (INIS)

    Teates, C.D.; Bezirdjian, D.R.; Bray, S.T.; Tegtmeyer, C.J.

    1981-01-01

    The hospital and departmental records of the University of Virginia Medical Center from 1976 to 1980 show an increasing frequency of ventilation studies relative to perfusion studies and a decrease in frequency of ventilation-perfusion diagnosis of pulmonary embolus. Pulmonary angiograms have increased from one per 68 nuclear studies to one per 14. A review of 70 patients with correlating angiography or autopsy shows that 89% of nuclear studies were accurate. We have revised our interpretation criteria and indications for pulmonary angiography

  13. HALO: a reconfigurable image enhancement and multisensor fusion system

    Science.gov (United States)

    Wu, F.; Hickman, D. L.; Parker, Steve J.

    2014-06-01

    Contemporary high definition (HD) cameras and affordable infrared (IR) imagers are set to dramatically improve the effectiveness of security, surveillance and military vision systems. However, the quality of imagery is often compromised by camera shake, or poor scene visibility due to inadequate illumination or bad atmospheric conditions. A versatile vision processing system called HALO™ is presented that can address these issues, by providing flexible image processing functionality on a low size, weight and power (SWaP) platform. Example processing functions include video distortion correction, stabilisation, multi-sensor fusion and image contrast enhancement (ICE). The system is based around an all-programmable system-on-a-chip (SoC), which combines the computational power of a field-programmable gate array (FPGA) with the flexibility of a CPU. The FPGA accelerates computationally intensive real-time processes, whereas the CPU provides management and decision making functions that can automatically reconfigure the platform based on user input and scene content. These capabilities enable a HALO™ equipped reconnaissance or surveillance system to operate in poor visibility, providing potentially critical operational advantages in visually complex and challenging usage scenarios. The choice of an FPGA based SoC is discussed, and the HALO™ architecture and its implementation are described. The capabilities of image distortion correction, stabilisation, fusion and ICE are illustrated using laboratory and trials data.

  14. Hybrid Histogram Descriptor: A Fusion Feature Representation for Image Retrieval.

    Science.gov (United States)

    Feng, Qinghe; Hao, Qiaohong; Chen, Yuqi; Yi, Yugen; Wei, Ying; Dai, Jiangyan

    2018-06-15

    Currently, visual sensors are becoming increasingly affordable and fashionable, acceleratingly the increasing number of image data. Image retrieval has attracted increasing interest due to space exploration, industrial, and biomedical applications. Nevertheless, designing effective feature representation is acknowledged as a hard yet fundamental issue. This paper presents a fusion feature representation called a hybrid histogram descriptor (HHD) for image retrieval. The proposed descriptor comprises two histograms jointly: a perceptually uniform histogram which is extracted by exploiting the color and edge orientation information in perceptually uniform regions; and a motif co-occurrence histogram which is acquired by calculating the probability of a pair of motif patterns. To evaluate the performance, we benchmarked the proposed descriptor on RSSCN7, AID, Outex-00013, Outex-00014 and ETHZ-53 datasets. Experimental results suggest that the proposed descriptor is more effective and robust than ten recent fusion-based descriptors under the content-based image retrieval framework. The computational complexity was also analyzed to give an in-depth evaluation. Furthermore, compared with the state-of-the-art convolutional neural network (CNN)-based descriptors, the proposed descriptor also achieves comparable performance, but does not require any training process.

  15. Multimodality imaging: transfer and fusion of SPECT and MRI data

    International Nuclear Information System (INIS)

    Knesaurek, K.

    1994-01-01

    Image fusion is a technique which offers the best of both worlds. It unites the two basic types of medical images: functional body images(PET or SPECT scans), which provide physiological information, and structural images (CT or MRI), which provide an anatomic map of the body. Control-point based registration technique was developed and used. Tc-99m point sources were used as external markers in SPECT studies while, for MRI and CT imaging only anatomic landmarks were used as a control points. The MRI images were acquired on GE Signa 1.2 system and CT data on a GE 9800 scanner. SPECT studies were performed 1h after intravenous injection of the 740 MBq of the Tc-99m-HMPAO on the triple-headed TRIONIX gamma camera. B-spline and bilinear interpolation were used for the rotation, scaling and translation of the images. In the process of creation of a single composite image, in order to retain information from the individual images, MRI (or CT) image was scaled to one color range and a SPECT image to another. In some situations the MRI image was kept black-and-white while the SPECT image was pasted on top of it in 'opaque' mode. Most errors which propagate through the matching process are due to sample size, imperfection of the acquisition system, noise and interpolations used. Accuracy of the registration was investigated by SPECT-CT study performed on a phantom study. The results has shown that accuracy of the matching process is better, or at worse, equal to 2 mm. (author)

  16. An enhanced approach for biomedical image restoration using image fusion techniques

    Science.gov (United States)

    Karam, Ghada Sabah; Abbas, Fatma Ismail; Abood, Ziad M.; Kadhim, Kadhim K.; Karam, Nada S.

    2018-05-01

    Biomedical image is generally noisy and little blur due to the physical mechanisms of the acquisition process, so one of the common degradations in biomedical image is their noise and poor contrast. The idea of biomedical image enhancement is to improve the quality of the image for early diagnosis. In this paper we are using Wavelet Transformation to remove the Gaussian noise from biomedical images: Positron Emission Tomography (PET) image and Radiography (Radio) image, in different color spaces (RGB, HSV, YCbCr), and we perform the fusion of the denoised images resulting from the above denoising techniques using add image method. Then some quantive performance metrics such as signal -to -noise ratio (SNR), peak signal-to-noise ratio (PSNR), and Mean Square Error (MSE), etc. are computed. Since this statistical measurement helps in the assessment of fidelity and image quality. The results showed that our approach can be applied of Image types of color spaces for biomedical images.

  17. Thought–shape fusion and body image in eating disorders

    Directory of Open Access Journals (Sweden)

    Jáuregui-Lobera I

    2012-10-01

    Full Text Available Ignacio Jáuregui-Lobera,1 Patricia Bolaños-Ríos,2 Inmaculada Ruiz-Prieto21Department of Nutrition and Bromatology, Pablo de Olavide University, Seville, Spain; 2Behavioral Sciences Institute, Seville, SpainPurpose: The aim of this study was to analyze the relationships among thought–shape fusion (TSF, specific instruments to assess body image disturbances, and body image quality of life in eating disorder patients in order to improve the understanding of the links between body image concerns and a specific bias consisting of beliefs about the consequences of thinking about forbidden foods.Patients and methods: The final sample included 76 eating disorder patients (mean age 20.13 ± 2.28 years; 59 women and seven men. After having obtained informed consent, the following questionnaires were administered: Body Appreciation Scale (BAS, Body Image Quality of Life Inventory (BIQLI-SP, Body Shape Questionnaire (BSQ, Eating Disorders Inventory-2 (EDI-2, State-Trait Anxiety Inventory (STAI, Symptom Checklist-90-Revised (SCL-90-R and Thought-Shape Fusion Questionnaire (TSF-Q.Results: Significant correlations were found between TSF-Q and body image-related variables. Those with higher scores in TSF showed higher scores in the BSQ (P < 0.0001, Eating Disorder Inventory – Drive for Thinness (EDI-DT (P < 0.0001, and Eating Disorder Inventory – Body Dissatisfaction (EDI-BD (P < 0.0001. The same patients showed lower scores in the BAS (P < 0.0001. With respect to the psychopathological variables, patients with high TSF obtained higher scores in all SCL-90-R subscales as well as in the STAI.Conclusion: The current study shows the interrelations among different body image-related variables, TSF, and body image quality of life.Keywords: cognitive distortions, quality of life, body appreciation, psychopathology, anorexia nervosa, bulimia nervosa

  18. [Research progress of multi-model medical image fusion and recognition].

    Science.gov (United States)

    Zhou, Tao; Lu, Huiling; Chen, Zhiqiang; Ma, Jingxian

    2013-10-01

    Medical image fusion and recognition has a wide range of applications, such as focal location, cancer staging and treatment effect assessment. Multi-model medical image fusion and recognition are analyzed and summarized in this paper. Firstly, the question of multi-model medical image fusion and recognition is discussed, and its advantage and key steps are discussed. Secondly, three fusion strategies are reviewed from the point of algorithm, and four fusion recognition structures are discussed. Thirdly, difficulties, challenges and possible future research direction are discussed.

  19. Robust Tomato Recognition for Robotic Harvesting Using Feature Images Fusion

    Directory of Open Access Journals (Sweden)

    Yuanshen Zhao

    2016-01-01

    Full Text Available Automatic recognition of mature fruits in a complex agricultural environment is still a challenge for an autonomous harvesting robot due to various disturbances existing in the background of the image. The bottleneck to robust fruit recognition is reducing influence from two main disturbances: illumination and overlapping. In order to recognize the tomato in the tree canopy using a low-cost camera, a robust tomato recognition algorithm based on multiple feature images and image fusion was studied in this paper. Firstly, two novel feature images, the  a*-component image and the I-component image, were extracted from the L*a*b* color space and luminance, in-phase, quadrature-phase (YIQ color space, respectively. Secondly, wavelet transformation was adopted to fuse the two feature images at the pixel level, which combined the feature information of the two source images. Thirdly, in order to segment the target tomato from the background, an adaptive threshold algorithm was used to get the optimal threshold. The final segmentation result was processed by morphology operation to reduce a small amount of noise. In the detection tests, 93% target tomatoes were recognized out of 200 overall samples. It indicates that the proposed tomato recognition method is available for robotic tomato harvesting in the uncontrolled environment with low cost.

  20. Robust Tomato Recognition for Robotic Harvesting Using Feature Images Fusion.

    Science.gov (United States)

    Zhao, Yuanshen; Gong, Liang; Huang, Yixiang; Liu, Chengliang

    2016-01-29

    Automatic recognition of mature fruits in a complex agricultural environment is still a challenge for an autonomous harvesting robot due to various disturbances existing in the background of the image. The bottleneck to robust fruit recognition is reducing influence from two main disturbances: illumination and overlapping. In order to recognize the tomato in the tree canopy using a low-cost camera, a robust tomato recognition algorithm based on multiple feature images and image fusion was studied in this paper. Firstly, two novel feature images, the  a*-component image and the I-component image, were extracted from the L*a*b* color space and luminance, in-phase, quadrature-phase (YIQ) color space, respectively. Secondly, wavelet transformation was adopted to fuse the two feature images at the pixel level, which combined the feature information of the two source images. Thirdly, in order to segment the target tomato from the background, an adaptive threshold algorithm was used to get the optimal threshold. The final segmentation result was processed by morphology operation to reduce a small amount of noise. In the detection tests, 93% target tomatoes were recognized out of 200 overall samples. It indicates that the proposed tomato recognition method is available for robotic tomato harvesting in the uncontrolled environment with low cost.

  1. Image quality and diagnostic accuracy of unenhanced SSFP MR angiography compared with conventional contrast-enhanced MR angiography for the assessment of thoracic aortic diseases

    Energy Technology Data Exchange (ETDEWEB)

    Krishnam, Mayil S. [University of California, Cardiovascular and Thoracic Imaging, UCI Medical Center, Irvine, CA (United States); Tomasian, Anderanik; Malik, Sachin; Ruehm, Stefan G. [University of California at Los Angeles, Department of Radiological Sciences, Ronald Reagan Medical Center, Los Angeles, CA (United States); Desphande, Vibhas; Laub, Gerhard [Siemens Medical Solutions, Los Angeles, CA (United States)

    2010-06-15

    The purpose of this study was to determine the image quality and diagnostic accuracy of three-dimensional (3D) unenhanced steady state free precession (SSFP) magnetic resonance angiography (MRA) for the evaluation of thoracic aortic diseases. Fifty consecutive patients with known or suspected thoracic aortic disease underwent free-breathing ECG-gated unenhanced SSFP MRA with non-selective radiofrequency excitation and contrast-enhanced (CE) MRA of the thorax at 1.5 T. Two readers independently evaluated the two datasets for image quality in the aortic root, ascending aorta, aortic arch, descending aorta, and origins of supra-aortic arteries, and for abnormal findings. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were determined for both datasets. Sensitivity, specificity, and diagnostic accuracy of unenhanced SSFP MRA for the diagnosis of aortic abnormalities were determined. Abnormal aortic findings, including aneurysm (n = 47), coarctation (n = 14), dissection (n = 12), aortic graft (n = 6), intramural hematoma (n = 11), mural thrombus in the aortic arch (n = 1), and penetrating aortic ulcer (n = 9), were confidently detected on both datasets. Sensitivity, specificity, and diagnostic accuracy of SSFP MRA for the detection of aortic disease were 100% with CE-MRA serving as a reference standard. Image quality of the aortic root was significantly higher on SSFP MRA (P < 0.001) with no significant difference for other aortic segments (P > 0.05). SNR and CNR values were higher for all segments on SSFP MRA (P < 0.01). Our results suggest that free-breathing navigator-gated 3D SSFP MRA with non-selective radiofrequency excitation is a promising technique that provides high image quality and diagnostic accuracy for the assessment of thoracic aortic disease without the need for intravenous contrast material. (orig.)

  2. Image quality and diagnostic accuracy of unenhanced SSFP MR angiography compared with conventional contrast-enhanced MR angiography for the assessment of thoracic aortic diseases

    International Nuclear Information System (INIS)

    Krishnam, Mayil S.; Tomasian, Anderanik; Malik, Sachin; Ruehm, Stefan G.; Desphande, Vibhas; Laub, Gerhard

    2010-01-01

    The purpose of this study was to determine the image quality and diagnostic accuracy of three-dimensional (3D) unenhanced steady state free precession (SSFP) magnetic resonance angiography (MRA) for the evaluation of thoracic aortic diseases. Fifty consecutive patients with known or suspected thoracic aortic disease underwent free-breathing ECG-gated unenhanced SSFP MRA with non-selective radiofrequency excitation and contrast-enhanced (CE) MRA of the thorax at 1.5 T. Two readers independently evaluated the two datasets for image quality in the aortic root, ascending aorta, aortic arch, descending aorta, and origins of supra-aortic arteries, and for abnormal findings. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were determined for both datasets. Sensitivity, specificity, and diagnostic accuracy of unenhanced SSFP MRA for the diagnosis of aortic abnormalities were determined. Abnormal aortic findings, including aneurysm (n = 47), coarctation (n = 14), dissection (n = 12), aortic graft (n = 6), intramural hematoma (n = 11), mural thrombus in the aortic arch (n = 1), and penetrating aortic ulcer (n = 9), were confidently detected on both datasets. Sensitivity, specificity, and diagnostic accuracy of SSFP MRA for the detection of aortic disease were 100% with CE-MRA serving as a reference standard. Image quality of the aortic root was significantly higher on SSFP MRA (P 0.05). SNR and CNR values were higher for all segments on SSFP MRA (P < 0.01). Our results suggest that free-breathing navigator-gated 3D SSFP MRA with non-selective radiofrequency excitation is a promising technique that provides high image quality and diagnostic accuracy for the assessment of thoracic aortic disease without the need for intravenous contrast material. (orig.)

  3. Comparison of virtual monoenergetic and polyenergetic images reconstructed from dual-layer detector CT angiography of the head and neck.

    Science.gov (United States)

    Neuhaus, Victor; Große Hokamp, Nils; Abdullayev, Nuran; Maus, Volker; Kabbasch, Christoph; Mpotsaris, Anastasios; Maintz, David; Borggrefe, Jan

    2018-03-01

    To compare the image quality of virtual monoenergetic images and polyenergetic images reconstructed from dual-layer detector CT angiography (DLCTA). Thirty patients who underwent DLCTA of the head and neck were retrospectively identified and polyenergetic as well as virtual monoenergetic images (40 to 120 keV) were reconstructed. Signals (± SD) of the cervical and cerebral vessels as well as lateral pterygoid muscle and the air surrounding the head were measured to calculate the CNR and SNR. In addition, subjective image quality was assessed using a 5-point Likert scale. Student's t-test and Wilcoxon test were used to determine statistical significance. Compared to polyenergetic images, although noise increased with lower keV, CNR (p 0.05) of the cervical, petrous and intracranial vessels were improved in virtual monoenergetic images at 40 keV and virtual monoenergetic images at 45 keV were also rated superior regarding vascular contrast, assessment of arteries close to the skull base and small arterial branches (p virtual monoenergetic images reconstructed from DLCTA at low keV ranging from 40 to 45 keV improve the objective and subjective image quality of extra- and intracranial vessels and facilitate assessment of vessels close to the skull base and of small arterial branches. • Virtual monoenergetic images greatly improve attenuation, while noise only slightly increases. • Virtual monoenergetic images show superior contrast-to-noise ratios compared to polyenergetic images. • Virtual monoenergetic images significantly improve image quality at low keV.

  4. System upgrade on Philips Allura FD20 angiography systems: effects on patient skin dose and static image quality

    International Nuclear Information System (INIS)

    Ryckx, Nick; Sans-Merce, Marta; Meuli, Reto; Zerlauth, Jean-Baptiste; Verdun, Francis R.

    2016-01-01

    Fluoroscopically guided procedures might be highly irradiating for patients, possibly leading to skin injuries. In such a context, every effort should be done to lower patient exposure as much as possible. Moreover, patient dose reduction does not only benefit to the patient but also allows reducing staff exposure. In this framework, Philips Healthcare recently introduced a system upgrade for their angiography units, called 'AlluraClarity'. The authors performed air kerma rate measurements for all available fluoroscopy modes and air kerma per frame measurements for the digital subtraction angiography protocols, along with subjective spatial resolution and low-contrast detectability assessments using a standard QA phantom. Air kerma reductions ranging from 25.5 to 84.4 % were found, with no significant change in image quality when switching from a standard operating mode to an upgraded version. These results are confirmed by the comparison of actual patient exposures for similar procedures. (authors)

  5. Coronary angiography using synchrotron radiation

    International Nuclear Information System (INIS)

    Akatsuka, Takao; Hiranaka, Yukio; Takeda, Tohru; Hyodo, Kazuyuki.

    1990-01-01

    Invasive coronary angiography is the imaging technique of choice for diagnosis of ischemic heart disease. Recently, the application of synchrotron radiation in coronary angiography has been investigated in the world, with the aim of developing the noninvasive technique for visualizing the heart. In this article, backgrounds and present situation of coronary angiography using synchrotron radiation are reviewed. Firstly, visual imaging techniques of the cardiovascular system are discussed in terms of angiography and digital subtraction angiography (DSA). Conventional temporal, energy, and hybrid subtraction modes used in DSA are referred to. Secondly, the application of synchrotron radiation is presented, focusing on the property of synchrotron radiation and K-edge subtraction angiography. Two kinds of synchrotron radiation beam methods are outlined. Interpretation of image data and various subtraction procedures remain unestablished. There is much to be done before coronary angiography using synchrotron radiation comes into a clinical practice. (N.K.)

  6. MRI angiography

    International Nuclear Information System (INIS)

    Poncelet, B.; Baleriiaux, D.; struyven, J.; Segebarth, C.

    1989-01-01

    In MRI angiography two basis images are measured which only differ by the signal intensity of the flowing blood in the vessels. Subtraction of these two images produces a high contrast-to-noise representation of the vessels. Contrast between stationary tissues and flowing blood is changed, for one image compared to the second one, using a selective modification of the phase of the signal from the flowing blood, and/or using a selective modification of its longitudinal magnetization: The macroscopic spin motions along the selection and the measurement gradient directions affect the phase of the nuclear signal; assuming constant velocity, the phase is proportional to the velocity and to the first moment of the gradient waveforms applied. This work concentrates on the generarion of MRI angiograms, following a phase-based approach, of the carotid bifurcation and of different intracranical regions including the carotid syphon and the circle of Willis. (author). 21 refs.; 3 figs

  7. Optical asymmetric watermarking using modified wavelet fusion and diffractive imaging

    Science.gov (United States)

    Mehra, Isha; Nishchal, Naveen K.

    2015-05-01

    In most of the existing image encryption algorithms the generated keys are in the form of a noise like distribution with a uniform distributed histogram. However, the noise like distribution is an apparent sign indicating the presence of the keys. If the keys are to be transferred through some communication channels, then this may lead to a security problem. This is because; the noise like features may easily catch people's attention and bring more attacks. To address this problem it is required to transfer the keys to some other meaningful images to disguise the attackers. The watermarking schemes are complementary to image encryption schemes. In most of the iterative encryption schemes, support constraints play an important role of the keys in order to decrypt the meaningful data. In this article, we have transferred the support constraints which are generated by axial translation of CCD camera using amplitude-, and phase- truncation approach, into different meaningful images. This has been done by developing modified fusion technique in wavelet transform domain. The second issue is, in case, the meaningful images are caught by the attacker then how to solve the copyright protection. To resolve this issue, watermark detection plays a crucial role. For this purpose, it is necessary to recover the original image using the retrieved watermarks/support constraints. To address this issue, four asymmetric keys have been generated corresponding to each watermarked image to retrieve the watermarks. For decryption, an iterative phase retrieval algorithm is applied to extract the plain-texts from corresponding retrieved watermarks.

  8. Fusion of PET and MRI for Hybrid Imaging

    Science.gov (United States)

    Cho, Zang-Hee; Son, Young-Don; Kim, Young-Bo; Yoo, Seung-Schik

    Recently, the development of the fusion PET-MRI system has been actively studied to meet the increasing demand for integrated molecular and anatomical imaging. MRI can provide detailed anatomical information on the brain, such as the locations of gray and white matter, blood vessels, axonal tracts with high resolution, while PET can measure molecular and genetic information, such as glucose metabolism, neurotransmitter-neuroreceptor binding and affinity, protein-protein interactions, and gene trafficking among biological tissues. State-of-the-art MRI systems, such as the 7.0 T whole-body MRI, now can visualize super-fine structures including neuronal bundles in the pons, fine blood vessels (such as lenticulostriate arteries) without invasive contrast agents, in vivo hippocampal substructures, and substantia nigra with excellent image contrast. High-resolution PET, known as High-Resolution Research Tomograph (HRRT), is a brain-dedicated system capable of imaging minute changes of chemicals, such as neurotransmitters and -receptors, with high spatial resolution and sensitivity. The synergistic power of the two, i.e., ultra high-resolution anatomical information offered by a 7.0 T MRI system combined with the high-sensitivity molecular information offered by HRRT-PET, will significantly elevate the level of our current understanding of the human brain, one of the most delicate, complex, and mysterious biological organs. This chapter introduces MRI, PET, and PET-MRI fusion system, and its algorithms are discussed in detail.

  9. Diagnostic accuracy of combined coronary angiography and adenosine stress myocardial perfusion imaging using 320-detector computed tomography: pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Nasis, Arthur; Ko, Brian S.; Leung, Michael C.; Antonis, Paul R.; Wong, Dennis T.; Kyi, Leo; Cameron, James D.; Meredith, Ian T.; Seneviratne, Sujith K. [Southern Health and Monash University, Monash Cardiovascular Research Centre, Monash Heart, Department of Medicine Monash Medical Centre (MMC), Melbourne (Australia); Nandurkar, Dee; Troupis, John M. [MMC, Southern Health, Department of Diagnostic Imaging, Melbourne (Australia)

    2013-07-15

    To determine the diagnostic accuracy of combined 320-detector row computed tomography coronary angiography (CTA) and adenosine stress CT myocardial perfusion imaging (CTP) in detecting perfusion abnormalities caused by obstructive coronary artery disease (CAD). Twenty patients with suspected CAD who underwent initial investigation with single-photon-emission computed tomography myocardial perfusion imaging (SPECT-MPI) were recruited and underwent prospectively-gated 320-detector CTA/CTP and invasive angiography. Two blinded cardiologists evaluated invasive angiography images quantitatively (QCA). A blinded nuclear physician analysed SPECT-MPI images for fixed and reversible perfusion defects. Two blinded cardiologists assessed CTA/CTP studies qualitatively. Vessels/territories with both >50 % stenosis on QCA and corresponding perfusion defect on SPECT-MPI were defined as ischaemic and formed the reference standard. All patients completed the CTA/CTP protocol with diagnostic image quality. Of 60 vessels/territories, 17 (28 %) were ischaemic according to QCA/SPECT-MPI criteria. Sensitivity, specificity, PPV, NPV and area under the ROC curve for CTA/CTP was 94 %, 98 %, 94 %, 98 % and 0.96 (P < 0.001) on a per-vessel/territory basis. Mean CTA/CTP radiation dose was 9.2 {+-} 7.4 mSv compared with 13.2 {+-} 2.2 mSv for SPECT-MPI (P < 0.001). Combined 320-detector CTA/CTP is accurate in identifying obstructive CAD causing perfusion abnormalities compared with combined QCA/SPECT-MPI, achieved with lower radiation dose than SPECT-MPI. (orig.)

  10. Diagnostic accuracy of combined coronary angiography and adenosine stress myocardial perfusion imaging using 320-detector computed tomography: pilot study

    International Nuclear Information System (INIS)

    Nasis, Arthur; Ko, Brian S.; Leung, Michael C.; Antonis, Paul R.; Wong, Dennis T.; Kyi, Leo; Cameron, James D.; Meredith, Ian T.; Seneviratne, Sujith K.; Nandurkar, Dee; Troupis, John M.

    2013-01-01

    To determine the diagnostic accuracy of combined 320-detector row computed tomography coronary angiography (CTA) and adenosine stress CT myocardial perfusion imaging (CTP) in detecting perfusion abnormalities caused by obstructive coronary artery disease (CAD). Twenty patients with suspected CAD who underwent initial investigation with single-photon-emission computed tomography myocardial perfusion imaging (SPECT-MPI) were recruited and underwent prospectively-gated 320-detector CTA/CTP and invasive angiography. Two blinded cardiologists evaluated invasive angiography images quantitatively (QCA). A blinded nuclear physician analysed SPECT-MPI images for fixed and reversible perfusion defects. Two blinded cardiologists assessed CTA/CTP studies qualitatively. Vessels/territories with both >50 % stenosis on QCA and corresponding perfusion defect on SPECT-MPI were defined as ischaemic and formed the reference standard. All patients completed the CTA/CTP protocol with diagnostic image quality. Of 60 vessels/territories, 17 (28 %) were ischaemic according to QCA/SPECT-MPI criteria. Sensitivity, specificity, PPV, NPV and area under the ROC curve for CTA/CTP was 94 %, 98 %, 94 %, 98 % and 0.96 (P < 0.001) on a per-vessel/territory basis. Mean CTA/CTP radiation dose was 9.2 ± 7.4 mSv compared with 13.2 ± 2.2 mSv for SPECT-MPI (P < 0.001). Combined 320-detector CTA/CTP is accurate in identifying obstructive CAD causing perfusion abnormalities compared with combined QCA/SPECT-MPI, achieved with lower radiation dose than SPECT-MPI. (orig.)

  11. Region-based multifocus image fusion for the precise acquisition of Pap smear images.

    Science.gov (United States)

    Tello-Mijares, Santiago; Bescós, Jesús

    2018-05-01

    A multifocus image fusion method to obtain a single focused image from a sequence of microscopic high-magnification Papanicolau source (Pap smear) images is presented. These images, captured each in a different position of the microscope lens, frequently show partially focused cells or parts of cells, which makes them unpractical for the direct application of image analysis techniques. The proposed method obtains a focused image with a high preservation of original pixels information while achieving a negligible visibility of the fusion artifacts. The method starts by identifying the best-focused image of the sequence; then, it performs a mean-shift segmentation over this image; the focus level of the segmented regions is evaluated in all the images of the sequence, and best-focused regions are merged in a single combined image; finally, this image is processed with an adaptive artifact removal process. The combination of a region-oriented approach, instead of block-based approaches, and a minimum modification of the value of focused pixels in the original images achieve a highly contrasted image with no visible artifacts, which makes this method especially convenient for the medical imaging domain. The proposed method is compared with several state-of-the-art alternatives over a representative dataset. The experimental results show that our proposal obtains the best and more stable quality indicators. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  12. A method based on IHS cylindrical transform model for quality assessment of image fusion

    Science.gov (United States)

    Zhu, Xiaokun; Jia, Yonghong

    2005-10-01

    Image fusion technique has been widely applied to remote sensing image analysis and processing, and methods for quality assessment of image fusion in remote sensing have also become the research issues at home and abroad. Traditional assessment methods combine calculation of quantitative indexes and visual interpretation to compare fused images quantificationally and qualitatively. However, in the existing assessment methods, there are two defects: on one hand, most imdexes lack the theoretic support to compare different fusion methods. On the hand, there is not a uniform preference for most of the quantitative assessment indexes when they are applied to estimate the fusion effects. That is, the spatial resolution and spectral feature could not be analyzed synchronously by these indexes and there is not a general method to unify the spatial and spectral feature assessment. So in this paper, on the basis of the approximate general model of four traditional fusion methods, including Intensity Hue Saturation(IHS) triangle transform fusion, High Pass Filter(HPF) fusion, Principal Component Analysis(PCA) fusion, Wavelet Transform(WT) fusion, a correlation coefficient assessment method based on IHS cylindrical transform is proposed. By experiments, this method can not only get the evaluation results of spatial and spectral features on the basis of uniform preference, but also can acquire the comparison between fusion image sources and fused images, and acquire differences among fusion methods. Compared with the traditional assessment methods, the new methods is more intuitionistic, and in accord with subjective estimation.

  13. A novel fusion imaging system for endoscopic ultrasound

    DEFF Research Database (Denmark)

    Gruionu, Lucian Gheorghe; Saftoiu, Adrian; Gruionu, Gabriel

    2016-01-01

    BACKGROUND AND OBJECTIVE: Navigation of a flexible endoscopic ultrasound (EUS) probe inside the gastrointestinal (GI) tract is problematic due to the small window size and complex anatomy. The goal of the present study was to test the feasibility of a novel fusion imaging (FI) system which uses...... time was 24.6 ± 6.6 min, while the time to reach the clinical target was 8.7 ± 4.2 min. CONCLUSIONS: The FI system is feasible for clinical use, and can reduce the learning curve for EUS procedures and improve navigation and targeting in difficult anatomic locations....

  14. Diagnostic imaging of acute aortic dissection; Evaluation of thrombosed type aortic dissection by CT and angiography

    Energy Technology Data Exchange (ETDEWEB)

    Ohya, Tohru; Kumazaki, Tatsuo (Nippon Medical School, Tokyo (Japan))

    1991-01-01

    One hundred and nineteen patients with aortic dissection who underwent diagnostic imaging were reviewed and angiographic findings as well as those of CT were analysed. Thirty eight cases (43.1%) had non-contrast opacified false lumen, the type of which we call 'thrombosed type aortic dissection'. A comparative study of the thrombosed type with the patent type of false lumens was made particularly from the stand point of the characteristic diagnostic imagings (CT and angiography). At the same time, the pitfalls of these imagings in thrombosed type aortic dissection were studied. At the onset the average age of thrombosed type was 62.3 years old, while that of the patent type was 57.3. A statistical significance between the two groups was p<0.05. Thrombosed type in all cases was caused by atherosclerosis, whereas patent type was caused by the Marfan's syndrome in 11 cases. Other clinical findings, such as initial symptoms and blood pressure revealed no significant differences between the two groups. Pre-contrast CT in acute thrombosed type aortic dissection showed 'hyperdense crescent sign' in 89.4%. However, in 3 cases with thrombosed type in which the pre-contrast CT showed 'hyperdense crescent sign' contrast-enhanced CT detected no clear evidence of aortic dissection in the same site. This was due to obscurity induced by contrast medium. Angiographic findings of thrombosed type were classified into 3 groups: normal type, stenosed true lumen type and ulcer-like projection type. The incidence of normal type was estimated to be 48.4%, whereas stenosed true lumen type was 24.2% and ulcer-like projection was 27.7%. The present study concluded that thrombosed type is not rare in acute aortic dissection and contrast-enhanced CT as well as pre-contrast CT, is of great value in diagnosing thrombosed type. 'Hyperdense crescent sign' in pre-contrast CT is characteristic of intramural hematoma. (author).

  15. Radiation dose reduction without compromise to image quality by alterations of filtration and focal spot size in cerebral angiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Joon; Park, Min Keun; Jung, Da Eun; Kang, Jung Han; Kim, Byung Moon [Dept. of Radiology, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2017-08-01

    Different angiographic protocols may influence the radiation dose and image quality. In this study, we aimed to investigate the effects of filtration and focal spot size on radiation dose and image quality for diagnostic cerebral angiography using an in-vitro model and in-vivo patient groups. Radiation dose and image quality were analyzed by varying the filtration and focal spot size on digital subtraction angiography exposure protocols (1, inherent filtration + large focus; 2, inherent + small; 3, copper + large; 4, copper + small). For the in-vitro analysis, a phantom was used for comparison of radiation dose. For the in-vivo analysis, bilateral paired injections, and patient cohort groups were compared for radiation dose and image quality. Image quality analysis was performed in terms of contrast, sharpness, noise, and overall quality. In the in-vitro analysis, the mean air kerma (AK) and dose area product (DAP)/frame were significantly lower with added copper filtration (protocols 3 and 4). In the in-vivo bilateral paired injections, AK and DAP/frame were significantly lower with filtration, without significant difference in image quality. The patient cohort groups with added filtration (protocols 3 and 4) showed significant reduction of total AK and DAP/patient without compromise to the image quality. Variations in focal spot size showed no significant differences in radiation dose and image quality. Addition of filtration for angiographic exposure studies can result in significant total radiation dose reduction without loss of image quality. Focal spot size does not influence radiation dose and image quality. The routine angiographic protocol should be judiciously investigated and implemented.

  16. Tissue identification with micro-magnetic resonance imaging in a caprine spinal fusion model

    NARCIS (Netherlands)

    Uffen, M.; Krijnen, M.; Hoogendoorn, R.; Strijkers, G.; Everts, V.; Wuisman, P.; Smit, T.

    2008-01-01

    Nonunion is a major complication of spinal interbody fusion. Currently X-ray and computed tomography (CT) are used for evaluating the spinal fusion process. However, both imaging modalities have limitations in judgment of the early stages of this fusion process, as they only visualize mineralized

  17. Prediction of the microsurgical window for skull-base tumors by advanced three-dimensional multi-fusion volumetric imaging

    International Nuclear Information System (INIS)

    Oishi, Makoto; Fukuda, Masafumi; Saito, Akihiko; Hiraishi, Tetsuya; Fujii, Yukihiko; Ishida, Go

    2011-01-01

    The surgery of skull base tumors (SBTs) is difficult due to the complex and narrow surgical window that is restricted by the cranium and important structures. The utility of three-dimensional multi-fusion volumetric imaging (3-D MFVI) for visualizing the predicted window for SBTs was evaluated. Presurgical simulation using 3-D MFVI was performed in 32 patients with SBTs. Imaging data were collected from computed tomography, magnetic resonance imaging, and digital subtraction angiography. Skull data was processed to imitate actual bone resection and integrated with various structures extracted from appropriate imaging modalities by image-analyzing software. The simulated views were compared with the views obtained during surgery. All craniotomies and bone resections except opening of the acoustic canal in 2 patients were performed as simulated. The simulated window allowed observation of the expected microsurgical anatomies including tumors, vasculatures, and cranial nerves, through the predicted operative window. We could not achieve the planned tumor removal in only 3 patients. 3-D MFVI afforded high quality images of the relevant microsurgical anatomies during the surgery of SBTs. The intraoperative deja-vu effect of the simulation increased the confidence of the surgeon in the planned surgical procedures. (author)

  18. IMPROVING THE QUALITY OF NEAR-INFRARED IMAGING OF IN VIVOBLOOD VESSELS USING IMAGE FUSION METHODS

    DEFF Research Database (Denmark)

    Jensen, Andreas Kryger; Savarimuthu, Thiusius Rajeeth; Sørensen, Anders Stengaard

    2009-01-01

    We investigate methods for improving the visual quality of in vivo images of blood vessels in the human forearm. Using a near-infrared light source and a dual CCD chip camera system capable of capturing images at visual and nearinfrared spectra, we evaluate three fusion methods in terms...... of their capability of enhancing the blood vessels while preserving the spectral signature of the original color image. Furthermore, we investigate a possibility of removing hair in the images using a fusion rule based on the "a trous" stationary wavelet decomposition. The method with the best overall performance...... with both speed and quality in mind is the Intensity Injection method. Using the developed system and the methods presented in this article, it is possible to create images of high visual quality with highly emphasized blood vessels....

  19. Analysis and Evaluation of IKONOS Image Fusion Algorithm Based on Land Cover Classification

    Institute of Scientific and Technical Information of China (English)

    Xia; JING; Yan; BAO

    2015-01-01

    Different fusion algorithm has its own advantages and limitations,so it is very difficult to simply evaluate the good points and bad points of the fusion algorithm. Whether an algorithm was selected to fuse object images was also depended upon the sensor types and special research purposes. Firstly,five fusion methods,i. e. IHS,Brovey,PCA,SFIM and Gram-Schmidt,were briefly described in the paper. And then visual judgment and quantitative statistical parameters were used to assess the five algorithms. Finally,in order to determine which one is the best suitable fusion method for land cover classification of IKONOS image,the maximum likelihood classification( MLC) was applied using the above five fusion images. The results showed that the fusion effect of SFIM transform and Gram-Schmidt transform were better than the other three image fusion methods in spatial details improvement and spectral information fidelity,and Gram-Schmidt technique was superior to SFIM transform in the aspect of expressing image details. The classification accuracy of the fused image using Gram-Schmidt and SFIM algorithms was higher than that of the other three image fusion methods,and the overall accuracy was greater than 98%. The IHS-fused image classification accuracy was the lowest,the overall accuracy and kappa coefficient were 83. 14% and 0. 76,respectively. Thus the IKONOS fusion images obtained by the Gram-Schmidt and SFIM were better for improving the land cover classification accuracy.

  20. Fusion of different modalities of imaging the fist

    International Nuclear Information System (INIS)

    Verdenet, J.; Garbuio, P.; Runge, M.; Cardot, J.C.

    1997-01-01

    The standard radiographical pictures are not able always to bring out the fracture of one of the fist bones. In an early study it was shown that 40% of patients presenting a suspicion of fracture and in which the radio- image was normal, have had a fracture confirmed with quantification by MRI and scintigraphy. The last one does not allow to specify the localization and consequently we developed a code to fusion entirely automatically the radiologic image and the scintigraphic image using no external marker. The code has been installed on a PC and uses the Matlab environment. Starting from the histogram processing the contours are individualized on the interpolated radio- and scinti-images. For matching there are 3 freedom degrees: one of rotation and 2 of translation (in x and y axes). The internal axes of the forearm was chosen to effect the rotation and translation. The forehand thickness, identical for each modality, allows to match properly the images. We have obtained an anatomic image on which the contour and the hyper-fixating zones of the scintigraphy are added. On a set of 100 examinations we observed 38 fractures while the difference between a fracture of the scaphoid and of another fist bone is confirmed in 93% of cases

  1. Myocardial perfusion imaging, coronary angiography and histological examination in experimental treatment of Ad-HGF for myocardial infarction

    International Nuclear Information System (INIS)

    Li Jianhua; Feng Jianlin; Cheng Xu; Li Dianfu; Zhang Youfu

    2007-01-01

    Objective: Gene therapy has drawn a great attention. A swine model of adenovirus hepatocyte growth factor(Ad-HGF) treated myocardial infarction(MI) was utilized, with the effect being assessed by rest myocardial perfusion imaging, coronary angiography and histological examination. Methods: Three groups of MI swine treated with Ad-HGF at low dose [n=5, Ad-HGF 10 8 plague forming unit (PFU)/ site], medium dose(n=5, 4 x 10 8 PFU/site), and high dose (n=5, 5 x 10 9 PFU/site), a control group treated with normal saline(NS, n=5) and a blank control group (n=5) underwent rest myocardial perfusion imaging and coronary angiography before and after treatment. The imaging results were analyzed along with histological findings in each group. Results: The state of myocardial perfusion and Rentrop scores remained unchanged in the blank control and NS groups after treatment. Whereas there was a significant improvement in the two variables in all three groups treated with Ad-HGF. The scores of left circumflex coronary artery (LCX) before and after treated were 7.8 ± 1.3 and 16.4 ± 1.1 (low-dose), 8.2 ± 1.6 and 17.6 ± 0.9 (medium-dose), 8.4 ± 1.5 and 19.0 ± 0.7 (high-dose), respectively. No significant differences were noted among the 3 groups. The number of vessels of NS group was markedly less than that of other groups. Conclusion: Myocardial perfusion imaging seems to be more accurate than coronary angiography and histological examination in evaluating the effects of Ad-HGF on myocardial infarction. (authors)

  2. Reconstructions with identical filling (RIF) of the heart: a physiological approach to image reconstruction in coronary CT angiography

    International Nuclear Information System (INIS)

    Reinartz, S.D.; Diefenbach, B.S.; Kuhl, C.K.; Mahnken, A.H.; Allmendinger, T.

    2012-01-01

    To compare image quality in coronary artery computed tomography angiography (cCTA) using reconstructions with automated phase detection and Reconstructions computed with Identical Filling of the heart (RIF). Seventy-four patients underwent ECG-gated dual source CT (DSCT) between November 2009 and July 2010 for suspected coronary heart disease (n = 35), planning of transcatheter aortic valve replacement (n = 34) or evaluation of ventricular function (n = 5). Image data sets by the RIF formula and automated phase detection were computed and evaluated with the AHA 15-segment model and a 5-grade Likert scale (1: poor, 5: excellent quality). Subgroups regarding rhythm (sinus rhythm = SR; arrhythmia = ARR) and potential premedication were evaluated by a per-segment, per-vessel and per-patient analysis. RIF significantly improved image quality in 10 of 15 coronary segments (P < 0.05). More diagnostic segments were provided by RIF regarding the entire cohort (n = 693 vs. 590, P < 0.001) and all of the subgroups (e.g. ARR: n = 143 vs. 72, P < 0.001). In arrhythmic patients (n = 19), more diagnostic vessels (e.g. LAD: n = 10 vs. 3; P < 0.014) and complete data sets (n = 7 vs. 1; P < 0.001) were produced. RIF reconstruction is superior to automatic diastolic non-edited reconstructions, especially in arrhythmic patients. RIF theory provides a physiological approach for determining the optimal image reconstruction point in ECG-gated CT angiography. (orig.)

  3. Catheter Angiography

    Medline Plus

    Full Text Available ... Angiography is a minimally invasive medical test that helps physicians diagnose and treat medical conditions. Angiography uses ... has narrowed the arteries to the legs and help prepare for endovascular intervention or surgery. detect disease ...

  4. Catheter Angiography

    Medline Plus

    Full Text Available ... you are pregnant and discuss any recent illnesses, medical conditions, medications you're taking and allergies, especially ... is Catheter Angiography? Angiography is a minimally invasive medical test that helps physicians diagnose and treat medical ...

  5. Catheter Angiography

    Medline Plus

    Full Text Available ... lies. The catheter used in angiography is a long plastic tube about as thick as a strand of spaghetti. top of page How does the procedure work? Catheter angiography works much the same as a ...

  6. New asymptomatic ischemic lesions on diffusion-weighted imaging after cerebral angiography

    International Nuclear Information System (INIS)

    Shibazaki, Kensaku

    2006-01-01

    Conventional cerebral angiography (CAG) is relatively low risk for neurological complications. However, diffusion-weighted imaging (DWI) after CAG occasionally reveal an asymptomatic ischemic lesion on the brain. The aim of this study was to investigate the frequency of new asymptomatic or symptomatic DWI lesions after CAG and to clarify the factors associated with them. Fifty-six patients with acute ischemic stroke and transient ischemic attack were prospectively enrolled. Magnetic resonance imaging (MRI) studies including DWI were studied twice, within 48 hours before and after CAG. The following factors were assessed; age, gender, history of stroke, history of ischemic heart disease, vascular risk factors, National Institutes of Health Stroke Scale (NIHSS) score on admission, stroke subtype, treatment before stroke or transient ischemic attack (TIA) (antiplatelets or warfarin), approach for catheters (transbrachial or femoral artery), amount of contrast medium used, length of the angiographic procedure, and fluoroscophy time. We divided the patients into two groups according to the presence of new DWI lesions after CAG; Positive group had new DWI lesions, whereas the Negative group had none. After CAG, no patients had new neurological deficits. New asymptomatic DWI lesions were observed in 24 patients (42.9%). The significant differences observed between two groups were as follows; age (69.8±11.3 for the Positive group versus 61.9±11.3 for the Negative group, p=0.043), female (54% versus 28%, p=0.048), non-small vessel occlusion (100% versus 66%, p=0.009), catheter approach for transfemoral artery (63% versus 13%, p<0.001), mean length of the angiographic procedure (63.1±21.6 min versus 43.7±14.2 min, p<0.001), mean fluoroscopy time (26.5±13.0 min versus 14.9±5.9 mm, p<0.001). Sensitivity and specificity analysis to discriminate the positive and negative groups revealed 17 minutes to be the critical threshold point (sensitivity 66.6% and specificity 68

  7. Feasibility of coronary calcium and stent image subtraction using 320-detector row CT angiography

    DEFF Research Database (Denmark)

    Fuchs, Andreas; Kühl, J Tobias; Chen, Marcus Y

    2015-01-01

    BACKGROUND: The reader confidence and diagnostic accuracy of coronary CT angiography (CCTA) can be compromised by the presence of calcified plaques and stents causing blooming artifacts. Compared to conventional invasive coronary angiography (ICA), this may cause an overestimation of stenosis....... We defined target segments on CCTAconv as motion-free coronary segments with calcification or stent and low reader confidence. The effect of CCTAsub was assessed. No approval from the ethics committee was required according to Danish law. RESULTS: A total of 76 target segments were identified...

  8. Improving the image quality of contrast-enhanced MR angiography by automated image registration: A prospective study in peripheral arterial disease of the lower extremities

    International Nuclear Information System (INIS)

    Menke, Jan

    2010-01-01

    Objective: If a patient has moved during digital subtraction angiography (DSA), manual pixel shift can improve the image quality. This study investigated whether such image registration can also improve the quality of contrast-enhanced magnetic resonance angiography (MRA) in patients with peripheral arterial disease of the lower extremities. Materials and methods: 404 leg MRAs of patients likely to have peripheral artery disease were included in this prospective study. The standard non-registered MRAs were compared to automatically linear, affine and warp registered MRAs by four image quality parameters, including the vessel detection probability (VDP) in maximum intensity projection (MIP) images and contrast-to-noise ratios (CNR). The different registration types were compared by analysis of variance. Results: All studied image quality parameters showed similar trends. Generally, registration improved the leg MRA quality significantly (P < 0.05). The 12% of lower legs with a body shift of 1 mm or more showed the highest gain in image quality when using linear registration instead of no registration, with an average VDP gain of 20-49%. Warp registration improved the image quality slightly further. Conclusion: Automated image registration can improve the MRA image quality especially in the lower legs, which is comparable to the effect of pixel shift in DSA.

  9. Research and Realization of Medical Image Fusion Based on Three-Dimensional Reconstruction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A new medical image fusion technique is presented. The method is based on three-dimensional reconstruction. After reconstruction, the three-dimensional volume data is normalized by three-dimensional coordinate conversion in the same way and intercepted through setting up cutting plane including anatomical structure, as a result two images in entire registration on space and geometry are obtained and the images are fused at last.Compared with traditional two-dimensional fusion technique, three-dimensional fusion technique can not only resolve the different problems existed in the two kinds of images, but also avoid the registration error of the two kinds of images when they have different scan and imaging parameter. The research proves this fusion technique is more exact and has no registration, so it is more adapt to arbitrary medical image fusion with different equipments.

  10. Evaluation of multimodality imaging using image fusion with ultrasound tissue elasticity imaging in an experimental animal model.

    Science.gov (United States)

    Paprottka, P M; Zengel, P; Cyran, C C; Ingrisch, M; Nikolaou, K; Reiser, M F; Clevert, D A

    2014-01-01

    To evaluate the ultrasound tissue elasticity imaging by comparison to multimodality imaging using image fusion with Magnetic Resonance Imaging (MRI) and conventional grey scale imaging with additional elasticity-ultrasound in an experimental small-animal-squamous-cell carcinoma-model for the assessment of tissue morphology. Human hypopharynx carcinoma cells were subcutaneously injected into the left flank of 12 female athymic nude rats. After 10 days (SD ± 2) of subcutaneous tumor growth, sonographic grey scale including elasticity imaging and MRI measurements were performed using a high-end ultrasound system and a 3T MR. For image fusion the contrast-enhanced MRI DICOM data set was uploaded in the ultrasonic device which has a magnetic field generator, a linear array transducer (6-15 MHz) and a dedicated software package (GE Logic E9), that can detect transducers by means of a positioning system. Conventional grey scale and elasticity imaging were integrated in the image fusion examination. After successful registration and image fusion the registered MR-images were simultaneously shown with the respective ultrasound sectional plane. Data evaluation was performed using the digitally stored video sequence data sets by two experienced radiologist using a modified Tsukuba Elasticity score. The colors "red and green" are assigned for an area of soft tissue, "blue" indicates hard tissue. In all cases a successful image fusion and plan registration with MRI and ultrasound imaging including grey scale and elasticity imaging was possible. The mean tumor volume based on caliper measurements in 3 dimensions was ~323 mm3. 4/12 rats were evaluated with Score I, 5/12 rates were evaluated with Score II, 3/12 rates were evaluated with Score III. There was a close correlation in the fused MRI with existing small necrosis in the tumor. None of the scored II or III lesions was visible by conventional grey scale. The comparison of ultrasound tissue elasticity imaging enables a

  11. Comparison of virtual monoenergetic and polyenergetic images reconstructed from dual-layer detector CT angiography of the head and neck

    Energy Technology Data Exchange (ETDEWEB)

    Neuhaus, Victor; Grosse Hokamp, Nils; Abdullayev, Nuran; Maus, Volker; Kabbasch, Christoph; Mpotsaris, Anastasios; Maintz, David; Borggrefe, Jan [University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Cologne (Germany)

    2018-03-15

    To compare the image quality of virtual monoenergetic images and polyenergetic images reconstructed from dual-layer detector CT angiography (DLCTA). Thirty patients who underwent DLCTA of the head and neck were retrospectively identified and polyenergetic as well as virtual monoenergetic images (40 to 120 keV) were reconstructed. Signals (± SD) of the cervical and cerebral vessels as well as lateral pterygoid muscle and the air surrounding the head were measured to calculate the CNR and SNR. In addition, subjective image quality was assessed using a 5-point Likert scale. Student's t-test and Wilcoxon test were used to determine statistical significance. Compared to polyenergetic images, although noise increased with lower keV, CNR (p < 0.02) and SNR (p > 0.05) of the cervical, petrous and intracranial vessels were improved in virtual monoenergetic images at 40 keV and virtual monoenergetic images at 45 keV were also rated superior regarding vascular contrast, assessment of arteries close to the skull base and small arterial branches (p < 0.0001 each). Compared to polyenergetic images, virtual monoenergetic images reconstructed from DLCTA at low keV ranging from 40 to 45 keV improve the objective and subjective image quality of extra- and intracranial vessels and facilitate assessment of vessels close to the skull base and of small arterial branches. (orig.)

  12. Multi-focus Image Fusion Using Epifluorescence Microscopy for Robust Vascular Segmentation

    OpenAIRE

    Pelapur, Rengarajan; Prasath, Surya; Palaniappan, Kannappan

    2014-01-01

    We are building a computerized image analysis system for Dura Mater vascular network from fluorescence microscopy images. We propose a system that couples a multi-focus image fusion module with a robust adaptive filtering based segmentation. The robust adaptive filtering scheme handles noise without destroying small structures, and the multi focal image fusion considerably improves the overall segmentation quality by integrating information from multiple images. Based on the segmenta...

  13. Fusion

    CERN Document Server

    Mahaffey, James A

    2012-01-01

    As energy problems of the world grow, work toward fusion power continues at a greater pace than ever before. The topic of fusion is one that is often met with the most recognition and interest in the nuclear power arena. Written in clear and jargon-free prose, Fusion explores the big bang of creation to the blackout death of worn-out stars. A brief history of fusion research, beginning with the first tentative theories in the early 20th century, is also discussed, as well as the race for fusion power. This brand-new, full-color resource examines the various programs currently being funded or p

  14. Impact of a New Adaptive Statistical Iterative Reconstruction (ASIR)-V Algorithm on Image Quality in Coronary Computed Tomography Angiography.

    Science.gov (United States)

    Pontone, Gianluca; Muscogiuri, Giuseppe; Andreini, Daniele; Guaricci, Andrea I; Guglielmo, Marco; Baggiano, Andrea; Fazzari, Fabio; Mushtaq, Saima; Conte, Edoardo; Annoni, Andrea; Formenti, Alberto; Mancini, Elisabetta; Verdecchia, Massimo; Campari, Alessandro; Martini, Chiara; Gatti, Marco; Fusini, Laura; Bonfanti, Lorenzo; Consiglio, Elisa; Rabbat, Mark G; Bartorelli, Antonio L; Pepi, Mauro

    2018-03-27

    A new postprocessing algorithm named adaptive statistical iterative reconstruction (ASIR)-V has been recently introduced. The aim of this article was to analyze the impact of ASIR-V algorithm on signal, noise, and image quality of coronary computed tomography angiography. Fifty consecutive patients underwent clinically indicated coronary computed tomography angiography (Revolution CT; GE Healthcare, Milwaukee, WI). Images were reconstructed using filtered back projection and ASIR-V 0%, and a combination of filtered back projection and ASIR-V 20%-80% and ASIR-V 100%. Image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated for left main coronary artery (LM), left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA) and were compared between the different postprocessing algorithms used. Similarly a four-point Likert image quality score of coronary segments was graded for each dataset and compared. A cutoff value of P ASIR-V 0%, ASIR-V 100% demonstrated a significant reduction of image noise in all coronaries (P ASIR-V 0%, SNR was significantly higher with ASIR-V 60% in LM (P ASIR-V 0%, CNR for ASIR-V ≥60% was significantly improved in LM (P ASIR-V ≥80%. ASIR-V 60% had significantly better Likert image quality scores compared to ASIR-V 0% in segment-, vessel-, and patient-based analyses (P ASIR-V 60% provides the optimal balance between image noise, SNR, CNR, and image quality. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  15. CT-angiography source images indicate less fatal outcome despite coma of patients in the Basilar Artery International Cooperation Study.

    Science.gov (United States)

    Pallesen, Lars P; Khomenko, Andrei; Dzialowski, Imanuel; Barlinn, Jessica; Barlinn, Kristian; Zerna, Charlotte; van der Hoeven, Erik Jrj; Algra, Ale; Kapelle, L Jaap; Michel, Patrik; Bodechtel, Ulf; Demchuk, Andrew M; Schonewille, Wouter; Puetz, Volker

    2017-02-01

    Background Coma is associated with poor outcome in patients with basilar artery occlusion. Aims We sought to assess whether the posterior circulation Acute Stroke Prognosis Early CT Score and the Pons-Midbrain Index applied to CT angiography source images predict the outcome of comatose patients in the Basilar Artery International Cooperation Study. Methods Basilar Artery International Cooperation Study was a prospective, observational registry of patients with acute basilar artery occlusion with 48 recruiting centers worldwide. We applied posterior circulation Acute Stroke Prognosis Early CT Score and Pons-Midbrain Index to CT angiography source images of Basilar Artery International Cooperation Study patients who presented with coma. We calculated adjusted risk ratios to assess the association of dichotomized posterior circulation Acute Stroke Prognosis Early CT Score (≥8 vs. International Cooperation Study registry, CT angiography source images were available for review in 158 patients. Among these, 78 patients (49%) presented with coma. Compared to non-comatose patients, comatose patients were more likely to die (risk ratios 2.34; CI 95% 1.56-3.52) and less likely to have a favourable outcome (risk ratios 0.44; CI 95% 0.24-0.80). Among comatose patients, a Pons-Midbrain Index < 3 was related to reduced mortality (adjusted RR 0.66; 95% CI 0.46-0.96), but not to favourable outcome (adjusted RR 1.19; 95% CI 0.39-3.62). Posterior circulation Acute Stroke Prognosis Early CT Score dichotomized at ≥ 8 vs. <8 was not significantly associated with death (adjusted RR 0.70; 95% CI 0.46-1.05). Conclusion In comatose patients with basilar artery occlusion, the extent of brainstem ischemia appears to be related to mortality but not to favourable outcome.

  16. Advantages of T2 reversed fast spin-echo image and enhanced three-dimensional surface MR angiography for the diagnosis of cerebral arteriovenous malformations

    International Nuclear Information System (INIS)

    Tanabe, Sumiyoshi; Honmou, Osamu; Minamida, Yoshihiro; Hashi, Kazuo

    2001-01-01

    Although the anatomical investigation of cerebral arteriovenous malformation (AVM) with conventional neuro-imagings considerably supports the preoperative evaluation, it is still hard to dissect the detailed anatomical conformations of AVMs such as location of nidus, identification of feeding arteries or draining veins, and the three-dimensional configuration of nidus in sulci or gyri. In this study, we investigated the efficacy of enhanced three-dimensional surface MR angiography (surface MRA) and T2 reversed image (T2R image) in the diagnosis and surgical planning for cerebral AVMs. The diagnostic accuracy was studied in twelve AVMs: four AVMs closed to motor area, one to Broca area, one to Wernicke area, four in temporal lobe, and two in occipital lobe. Images were obtained with a SIGNA HORIZON LX 1.5T VER 8.2. To construct T2R, the brain is scanned by fast SE method with long TR and was displayed with the reversed gray scale, which seemed similar to T1WI. Surface MRA is a fusion image of MRA and surface image in the workstation. The original data was obtained by enhanced 3D-SPGR method. MRA image was reconstructed with MIP method, and surface image was manipulated with a volume rendering method. T2R images demonstrated seven sulcal AVMs, three gyral AVMs, and two sulco-gyral AVMs; five AVMs located on cortex, four extended to subcortex, and three to paraventricular brain. The images clearly showed six AVMs had hypervascular network such as modja-modja vascular formation. Surface MRA represented nidus adjacent to eloquent area. They were present in central sulcus, precentral sulcus, intraparietal sulcus, inferior frontal sulcus, sylvian fissure, superior temporal sulcus, inferior temporal sulcus, superior temporal gyrus, inferior temporal gyrus, medial temporal gyrus, premotor area and superior frontal sulcus, precuneus and parieto-occipital sulcus. It was easy to identify the point of feeding arteries going down into the sulcus and the junction-point of nidus

  17. Advantages of T2 reversed fast spin-echo image and enhanced three-dimensional surface MR angiography for the diagnosis of cerebral arteriovenous malformations

    Energy Technology Data Exchange (ETDEWEB)

    Tanabe, Sumiyoshi; Honmou, Osamu; Minamida, Yoshihiro; Hashi, Kazuo [Sapporo Medical Univ. (Japan). School of Medicine

    2001-09-01

    Although the anatomical investigation of cerebral arteriovenous malformation (AVM) with conventional neuro-imagings considerably supports the preoperative evaluation, it is still hard to dissect the detailed anatomical conformations of AVMs such as location of nidus, identification of feeding arteries or draining veins, and the three-dimensional configuration of nidus in sulci or gyri. In this study, we investigated the efficacy of enhanced three-dimensional surface MR angiography (surface MRA) and T2 reversed image (T2R image) in the diagnosis and surgical planning for cerebral AVMs. The diagnostic accuracy was studied in twelve AVMs: four AVMs closed to motor area, one to Broca area, one to Wernicke area, four in temporal lobe, and two in occipital lobe. Images were obtained with a SIGNA HORIZON LX 1.5T VER 8.2. To construct T2R, the brain is scanned by fast SE method with long TR and was displayed with the reversed gray scale, which seemed similar to T1WI. Surface MRA is a fusion image of MRA and surface image in the workstation. The original data was obtained by enhanced 3D-SPGR method. MRA image was reconstructed with MIP method, and surface image was manipulated with a volume rendering method. T2R images demonstrated seven sulcal AVMs, three gyral AVMs, and two sulco-gyral AVMs; five AVMs located on cortex, four extended to subcortex, and three to paraventricular brain. The images clearly showed six AVMs had hypervascular network such as modja-modja vascular formation. Surface MRA represented nidus adjacent to eloquent area. They were present in central sulcus, precentral sulcus, intraparietal sulcus, inferior frontal sulcus, sylvian fissure, superior temporal sulcus, inferior temporal sulcus, superior temporal gyrus, inferior temporal gyrus, medial temporal gyrus, premotor area and superior frontal sulcus, precuneus and parieto-occipital sulcus. It was easy to identify the point of feeding arteries going down into the sulcus and the junction-point of nidus

  18. A Geometric Dictionary Learning Based Approach for Fluorescence Spectroscopy Image Fusion

    Directory of Open Access Journals (Sweden)

    Zhiqin Zhu

    2017-02-01

    Full Text Available In recent years, sparse representation approaches have been integrated into multi-focus image fusion methods. The fused images of sparse-representation-based image fusion methods show great performance. Constructing an informative dictionary is a key step for sparsity-based image fusion method. In order to ensure sufficient number of useful bases for sparse representation in the process of informative dictionary construction, image patches from all source images are classified into different groups based on geometric similarities. The key information of each image-patch group is extracted by principle component analysis (PCA to build dictionary. According to the constructed dictionary, image patches are converted to sparse coefficients by simultaneous orthogonal matching pursuit (SOMP algorithm for representing the source multi-focus images. At last the sparse coefficients are fused by Max-L1 fusion rule and inverted to fused image. Due to the limitation of microscope, the fluorescence image cannot be fully focused. The proposed multi-focus image fusion solution is applied to fluorescence imaging area for generating all-in-focus images. The comparison experimentation results confirm the feasibility and effectiveness of the proposed multi-focus image fusion solution.

  19. Diagnosis and screening of small hepatocellular carcinomas. Comparison of radionuclide imaging, ultrasound, computed tomography, hepatic angiography, and alpha 1-fetoprotein assay

    International Nuclear Information System (INIS)

    Takashima, T.; Matsui, O.; Suzuki, M.; Ida, M.

    1982-01-01

    Twenty-nine small (less than 5 cm) hepatocellular carcinomas in 18 patients were examined by radionuclide imaging (RN), ultrasound (US), computed tomography (CT), hepatic angiography, and serum alpha 1-fetoprotein (AFP) assay. Sensitivity was 39% with RN, 50% with US, 56% with CT, and 94% with angiography, including infusion hepatic angiography (IHA). Lesions larger than 3 cm could be detected by all of these methods; those between 2 and 3 cm were generally shown by US and CT but not RN. IHA was essential for diagnosis of lesions less than 2 cm, which were otherwise difficult or impossible to detect except with angiography. As a screening method, AFP was best, followed by US and CT. The authors recommend using AFP and US to minimize expense and radiation exposure. In questionable cases, IHA should be performed

  20. Nonlinear Geometric Warping of the Mask Image: A New Method for Reducing Misregistration Artifacts in Digital Subtraction Angiography

    International Nuclear Information System (INIS)

    Hayashi, Nobushige; Sakai, Toyohiko; Kitagawa, Manabu; Inagaki, Rika; Sadato, Norihiro; Ishii, Yasushi; Nishimoto, Yasuhiro; Tanaka, Masato; Fukushima, Tetsuya; Komuro, Hiroyuki; Ogura, Hisakazu; Kobayashi, Hidenori; Kubota, Toshihiko

    1998-01-01

    Purpose: Misregistration artifact is the major cause of image degradation in digital subtraction angiography (DSA). The purpose of this study was to evaluate the efficacy of a newly developed nonlinear geometric warping method to reduce misregistration artifact in DSA. Methods: The processing of the images was carried out on a workstation with a fully automatic computerized program. After making differential images with a lapracian filter, 49 regions of interest (ROIs) were set in the image to be processed. Each ROI of the live image scanned the corresponding ROI of the mask image searching for the best position to match itself. Each pixel of the mask image was shifted individually following the data calculated from the shifts of the ROIs. Five radiologists compared the images produced by the conventional parallel shift technique and those processed with this new method in 16 series of cerebral DSA. Results: In 14 of 16 series (88%), more radiologists judged the images processed with the new method to be better in quality. Small arteries near the skull base and veins of low density were clearly visualized in the images processed by the new method. Conclusion: This newly proposed method could be a simple and practical way to automatically reduce misregistration artifacts in DSA

  1. MR angiography of the cerebral vessels with inflow-increased visualization by overcontiguous imaging and advanced processing

    International Nuclear Information System (INIS)

    McLachian, S.; Simon, H.E.; de Graaf, R.; Ho, A.M.; Ruccio, W.J.; Steidley, J.W.; Pradhan, R.B.

    1989-01-01

    The purpose of this study was to increase the visualization of cerebral vessels with MR angiography by using an inflow technique from transverse sections. Difficulties with visualization include the tortuous nature of the vessels and slow blood flow. The MR method is a transverse two-dimensional multiple single-section sequence with a velocity-compensated gradient echo and presaturation. A S15 imager with 10-mTm gradients and a prototype angiographic package is used. Overcontiguous acquisition yields smaller effective center-to-center sections. Interpolation is used to generate interleaved plane projections. A combination of image parameter swill reduce the level of the stationary tissue relative to the flowing blood. For vessels that are not perpendicular to the section, overlapping the sections by 25%--33% is shown to reduce the staircase appearance without affecting the apparent size of the vessels. Interpolation of the MR images will further reduce this artifact, giving the vessels a smooth structure. MR angiography of the brain performed with an inflow technique allows the visualization of vessels in the brain even if the vessels follow tortuous paths. Presaturation and user-defined regions of interest can be used for ease of interpretation

  2. Digital image evaluation for the determination of morphometric sizes for periodontal X-ray diagnosis and selective coronary angiography

    International Nuclear Information System (INIS)

    Barth, K.

    1982-01-01

    In its uses in the areas of periodontology and coronary angiography it is shown, how the digital image evaluation expands the possibilities of x-ray diagnosis and how it improves the objectivity and exactness of the evaluation. For the accomplishment of this task a detailed analysis of the morphological data is undertaken. The results of the analysis lead to a mathematical structure model. Based on this model the recognition and measuring of the object in an adaptive heuristic process is undertaken. In this case it dealt with a desmodontal split, whose change is indicated by a periodontal bone atrophy. The contour recognition is embedded in a newly created image processing system, which allows itself to be used generally and is shown using the presentation of coronary vessels as an example. The exactness of the automatic image evaluation in comparison to the measuring done by the doctor is discussed. (orig./TRV) [de

  3. Multidetector-row computed tomography coronary angiography. Optimization of image reconstruction phase according to the heart rate

    International Nuclear Information System (INIS)

    Nagatani, Yukihiro; Takahashi, Masashi; Takazakura, Ryutaro; Nitta, Norihisa; Murata, Kiyoshi; Ushio, Noritoshi; Matsuo, Shinro; Yamamoto, Takashi; Horie, Minoru

    2007-01-01

    The purpose of this study was to optimize the image reconstruction phase of multidetector-row computed tomography (MDCT) coronary angiography according to the heart rate is crucial. Scan data were reconstructed for 10 different phases in 58 sequential patients who under went 8-row cardiac MDCT. The obtained images were scored and compared in terms of motion artifacts and visibility of the vessels, and moreover, electrocardiogram (ECG) record-based evaluations were added for clarification of the temporal relationships among these 10 phases. In the cases with lower heart rates ( 65 beats/mm), they were obtained in the late systolic period. As the heart rate increased, the optimal image reconstruction phase changed from mid diastole to late systole. However, it is recommended to try to decrease the heart rate of patients before data acquisition. (author)

  4. Extended depth of field integral imaging using multi-focus fusion

    Science.gov (United States)

    Piao, Yongri; Zhang, Miao; Wang, Xiaohui; Li, Peihua

    2018-03-01

    In this paper, we propose a new method for depth of field extension in integral imaging by realizing the image fusion method on the multi-focus elemental images. In the proposed method, a camera is translated on a 2D grid to take multi-focus elemental images by sweeping the focus plane across the scene. Simply applying an image fusion method on the elemental images holding rich parallax information does not work effectively because registration accuracy of images is the prerequisite for image fusion. To solve this problem an elemental image generalization method is proposed. The aim of this generalization process is to geometrically align the objects in all elemental images so that the correct regions of multi-focus elemental images can be exacted. The all-in focus elemental images are then generated by fusing the generalized elemental images using the block based fusion method. The experimental results demonstrate that the depth of field of synthetic aperture integral imaging system has been extended by realizing the generation method combined with the image fusion on multi-focus elemental images in synthetic aperture integral imaging system.

  5. Effective Multifocus Image Fusion Based on HVS and BP Neural Network

    Directory of Open Access Journals (Sweden)

    Yong Yang

    2014-01-01

    Full Text Available The aim of multifocus image fusion is to fuse the images taken from the same scene with different focuses to obtain a resultant image with all objects in focus. In this paper, a novel multifocus image fusion method based on human visual system (HVS and back propagation (BP neural network is presented. Three features which reflect the clarity of a pixel are firstly extracted and used to train a BP neural network to determine which pixel is clearer. The clearer pixels are then used to construct the initial fused image. Thirdly, the focused regions are detected by measuring the similarity between the source images and the initial fused image followed by morphological opening and closing operations. Finally, the final fused image is obtained by a fusion rule for those focused regions. Experimental results show that the proposed method can provide better performance and outperform several existing popular fusion methods in terms of both objective and subjective evaluations.

  6. CT angiography of intracranial arterial vessels: impact of tube voltage and contrast media concentration on image quality

    International Nuclear Information System (INIS)

    Ramgren, Birgitta; Holtaas, Stig; Siemund, Roger; Dept. of Radiology, Lund Univ., Lund

    2012-01-01

    Background Computed tomography angiography (CTA) of intracranial arteries has high demands on image quality. Important parameters influencing vessel enhancement are injection rate, concentration of contrast media and tube voltage. Purpose To evaluate the impact of an increase of contrast media concentration from 300 to 400 mg iodine/mL (mgI/mL) and the effect of a decrease of tube voltage from 120 to 90 kVp on vessel attenuation and image quality in CT angiography of intracranial arteries. Material and Methods Sixty-three patients were included into three protocol groups: Group I, 300 mgI/mL 120 kVp; Group II, 400 mgI/mL 120 kVp; Group III, 400 mgI/mL 90 kVp. Hounsfield units (HU) were measured in the internal carotid artery (ICA) and the M1 and M2 segments of the middle cerebral artery. Image quality grading was performed regarding M1 and M2 segments, volume rendering and general image impression. Results The difference in mean HU in ICA concerning the effect of contrast media concentration was statistically significant (P = 0.03) in favor of higher concentration. The difference in ICA enhancement due to the effect of tube voltage was statistically significant (P < 0.01) in favor of lower tube voltage. The increase of contrast medium concentration raised the mean enhancement in ICA with 18% and the decrease of tube voltage raised the mean enhancement with 37%. Image quality grading showed a trend towards improved grading for higher contrast concentration and lower tube voltage. Statistically significant better grading was found for the combined effect of both measures except for general impression (P 0.01-0.05). Conclusion The uses of highly concentrated contrast media and low tube voltage are easily performed measures to improve image quality in CTA of intracranial vessel

  7. Feasibility of magnetic resonance angiography (MRA) follow-up as the primary imaging modality after coiling of intracranial aneurysms

    International Nuclear Information System (INIS)

    Bakker, Nicolaas A.; Metzemaekers, Jan D. M.; Dijk, J. Marc C. van; Mooij, Jan Jakob A.; Groen, Rob J. M.; Westerlaan, Henriette E.; Eshghi, Omid S.

    2010-01-01

    Background: Digital subtraction angiography (DSA) is still regarded as the gold standard for detecting residual flow in treated aneurysms. Recent reports have also shown excellent results from magnetic resonance angiography (MRA) imaging. This is an important observation, since DSA is associated with a risk of medical complications, is time consuming, and is more expensive. Purpose: To determine whether MRA could replace conventional DSA and serve as the primary postinterventional imaging modality in patients with coiled intracranial aneurysms. Material and Methods: We studied a prospectively enrolled cohort of 190 patients treated endovascularly for a first-ruptured and/or unruptured intracranial aneurysm between January 2004 and December 2008. The imaging protocol included a 1.5T time-of-flight (TOF) MRA and a DSA at 3 months (on the same day) and, depending on comparability, a 1.5T TOF-MRA or DSA 1 year after treatment. All images were evaluated by a multidisciplinary panel. Results: In 141/190 patients, both an MRA and DSA were performed after 3-month follow-up. In 2/141 patients (1.4%), (small) neck remnants gave false-negative MRA results. In one patient (0.7%), this led to additional neurosurgical clipping of the aneurysm. In 25/141 patients, future follow-up (>3 months) consisted of DSA because of various reasons. In 24/25 of these patients, primary MRA images alone would invariably have led to additional DSA imaging. Conclusion: The present study shows that 1.5T TOF-MRA is a feasible primary follow-up modality after coiling of intracranial aneurysms. Given our data, we now suggest that, in every patient with a coiled intracranial aneurysm, the first follow-up, 3 months after coiling, should be an MRA study. Only when this MRA is inconclusive (e.g., because of coil artifacts), or in the case of suspicion of recanalization, should DSA be performed additionally

  8. Data fusion of Landsat TM and IRS images in forest classification

    Science.gov (United States)

    Guangxing Wang; Markus Holopainen; Eero Lukkarinen

    2000-01-01

    Data fusion of Landsat TM images and Indian Remote Sensing satellite panchromatic image (IRS-1C PAN) was studied and compared to the use of TM or IRS image only. The aim was to combine the high spatial resolution of IRS-1C PAN to the high spectral resolution of Landsat TM images using a data fusion algorithm. The ground truth of the study was based on a sample of 1,020...

  9. Prospective Electrocardiogram-Gated Multidetector Row Computed Tomography Coronary Angiography. Analysis of Quality Image and Radiation Dose

    International Nuclear Information System (INIS)

    Carrascosa, P.; Capunay, C.; Deviggiano, A.; Tajer, C.D.; Vallejos, J.; Goldsmit, A.; Garcia, M.J.

    2009-01-01

    Multidetector row computed tomography coronary angiography (MDCT-CA) has become a useful diagnostic tool for the direct quantification of coronary stenosis, for identifying coronary anomalies and for the assessment of coronary artery bypass grafts. Despite its clinical value has been questioned due to the effective radiation dose (ERD) received by each patient, radiation exposure is similar to other studies. However, different strategies are permanently tested in order to reduce the ERD maintaining adequate and diagnostic image quality. Objectives: To determine the image quality and effective radiation dose (ERD) of prospective electrocardiogram-gated multidetector row computed tomography coronary angiography (PMDCTCA) (the x-ray beam is turned on for only a short portion of diastole) compared to retrospective ECG gating (RMDCTCA) (the x-ray beam is turned on throughout the cardiac cycle) and a preliminary approach of its diagnostic accuracy compared to digital invasive coronary angiography (CA). Material and Methods: Fifty consecutive patients with suspected coronary artery disease and sinus rhythm were evaluated with PMDCT-CA and compared to a control group who underwent RMDCTCA. Image quality was analyzed by two reviewers. Interobserver concordance and ERD were determined. The diagnostic accuracy of PMDCT-CA compared to CA to detect coronary artery stenosis > 50% was assessed in 30 patients. Results: There were no significant differences in the image quality between both groups. Agreement between the reviewers for segment image quality scores was k = 0.92. Mean ERD was 3.5 mSv for PMDCT-CA compared to 9.7 and 12.9 mSv for RMDCT-CA with and without tube current modulation, respectively. Individual analysis including all segments showed that the sensitivity, specificity, positive predictive value and negative predictive value of PMDCT-CA for the detection of coronary stenosis were 94.74%, 81.82%, 90% and 90%, respectively. Conclusion: Our initial experience

  10. THERMAL AND VISIBLE SATELLITE IMAGE FUSION USING WAVELET IN REMOTE SENSING AND SATELLITE IMAGE PROCESSING

    Directory of Open Access Journals (Sweden)

    A. H. Ahrari

    2017-09-01

    Full Text Available Multimodal remote sensing approach is based on merging different data in different portions of electromagnetic radiation that improves the accuracy in satellite image processing and interpretations. Remote Sensing Visible and thermal infrared bands independently contain valuable spatial and spectral information. Visible bands make enough information spatially and thermal makes more different radiometric and spectral information than visible. However low spatial resolution is the most important limitation in thermal infrared bands. Using satellite image fusion, it is possible to merge them as a single thermal image that contains high spectral and spatial information at the same time. The aim of this study is a performance assessment of thermal and visible image fusion quantitatively and qualitatively with wavelet transform and different filters. In this research, wavelet algorithm (Haar and different decomposition filters (mean.linear,ma,min and rand for thermal and panchromatic bands of Landast8 Satellite were applied as shortwave and longwave fusion method . Finally, quality assessment has been done with quantitative and qualitative approaches. Quantitative parameters such as Entropy, Standard Deviation, Cross Correlation, Q Factor and Mutual Information were used. For thermal and visible image fusion accuracy assessment, all parameters (quantitative and qualitative must be analysed with respect to each other. Among all relevant statistical factors, correlation has the most meaningful result and similarity to the qualitative assessment. Results showed that mean and linear filters make better fused images against the other filters in Haar algorithm. Linear and mean filters have same performance and there is not any difference between their qualitative and quantitative results.

  11. Three-dimensional imaging of the optic nerve using magnetic resonance angiography. Application to anterior communicating artery aneurysm and craniopharingioma

    International Nuclear Information System (INIS)

    Okuyama, Tohru; Fukuyama, Atsushi; Fukuyama, Koichi; Ikeno, Kunihiro; Araki, Hiroyuki; Okada, Kinya; Sohma, Noriko

    2005-01-01

    The purpose of this investigation was to analyze three-dimensional images of the optic nerve obtained by magnetic resonance angiography (MRA) in cases of anterior communicating artery aneurysm and craniopharingioma. Four ruptured anterior communicating artery aneurysms, five non-ruptured anterior communicating artery aneurysms and two craniopharingiomas were examined. The images were taken using MR/i Hispeed Plus 1.5 T Infinity version, and analyzed by Advantage Work station AW4.1. The routine MR imaging parameters are shown in Table. The imaging time was about 10 minutes. Analysis was made by reformation of images parallel to the optic nerve obtained from the original MRA images. The optic nerve and brain tumor were traced with paintbrush from one sheet to another of the reformed images after subtraction of the blood vessels around the anterior communicating artery in these reformed images, and then three-dimensional images were constructed. Three-dimensional images of the blood vessels were reconstructed from MIP (maximum intensity projection) images using the threshold method. The optic nerve and anterior communicating arterial aneurysm or brain tumor were both observed in the overlapped 3D-SSD (shaded surface display) images. The analysis time was about 15 minutes. Three-dimensional images of the optic nerve and anterior communicating artery aneurysm or brain tumor were able to be made in all cases. As a preoperative investigation for anterior communicating artery aneurysm or suprasellar brain tumor, we considered that three-dimensional imaging of the optic nerve is useful in the operative approach because the optic nerve acts as a merkmal for the anterior communicating aneurysm or brain tumor. (author)

  12. Data and image fusion for geometrical cloud characterization

    Energy Technology Data Exchange (ETDEWEB)

    Thorne, L.R.; Buch, K.A.; Sun, Chen-Hui; Diegert, C.

    1997-04-01

    Clouds have a strong influence on the Earth`s climate and therefore on climate change. An important step in improving the accuracy of models that predict global climate change, general circulation models, is improving the parameterization of clouds and cloud-radiation interactions. Improvements in the next generation models will likely include the effect of cloud geometry on the cloud-radiation parameterizations. We have developed and report here methods for characterizing the geometrical features and three-dimensional properties of clouds that could be of significant value in developing these new parameterizations. We developed and report here a means of generating and imaging synthetic clouds which we used to test our characterization algorithms; a method for using Taylor`s hypotheses to infer spatial averages from temporal averages of cloud properties; a computer method for automatically classifying cloud types in an image; and a method for producing numerical three-dimensional renderings of cloud fields based on the fusion of ground-based and satellite images together with meteorological data.

  13. A color fusion method of infrared and low-light-level images based on visual perception

    Science.gov (United States)

    Han, Jing; Yan, Minmin; Zhang, Yi; Bai, Lianfa

    2014-11-01

    The color fusion images can be obtained through the fusion of infrared and low-light-level images, which will contain both the information of the two. The fusion images can help observers to understand the multichannel images comprehensively. However, simple fusion may lose the target information due to inconspicuous targets in long-distance infrared and low-light-level images; and if targets extraction is adopted blindly, the perception of the scene information will be affected seriously. To solve this problem, a new fusion method based on visual perception is proposed in this paper. The extraction of the visual targets ("what" information) and parallel processing mechanism are applied in traditional color fusion methods. The infrared and low-light-level color fusion images are achieved based on efficient typical targets learning. Experimental results show the effectiveness of the proposed method. The fusion images achieved by our algorithm can not only improve the detection rate of targets, but also get rich natural information of the scenes.

  14. An Integrated Dictionary-Learning Entropy-Based Medical Image Fusion Framework

    Directory of Open Access Journals (Sweden)

    Guanqiu Qi

    2017-10-01

    Full Text Available Image fusion is widely used in different areas and can integrate complementary and relevant information of source images captured by multiple sensors into a unitary synthetic image. Medical image fusion, as an important image fusion application, can extract the details of multiple images from different imaging modalities and combine them into an image that contains complete and non-redundant information for increasing the accuracy of medical diagnosis and assessment. The quality of the fused image directly affects medical diagnosis and assessment. However, existing solutions have some drawbacks in contrast, sharpness, brightness, blur and details. This paper proposes an integrated dictionary-learning and entropy-based medical image-fusion framework that consists of three steps. First, the input image information is decomposed into low-frequency and high-frequency components by using a Gaussian filter. Second, low-frequency components are fused by weighted average algorithm and high-frequency components are fused by the dictionary-learning based algorithm. In the dictionary-learning process of high-frequency components, an entropy-based algorithm is used for informative blocks selection. Third, the fused low-frequency and high-frequency components are combined to obtain the final fusion results. The results and analyses of comparative experiments demonstrate that the proposed medical image fusion framework has better performance than existing solutions.

  15. New method of digital angiography

    International Nuclear Information System (INIS)

    Hashiya, Junichi; Korenaga, Takeo; Sakurai, Kenji; Sakai, Fumikazu; Kato, Hisatoyo; Takano, Masao.

    1982-01-01

    New experience of digital angiography using Fuji Intelligent Diagnostic X-ray System was reported. The system utilizes newly developed high sensitivity imaging plate in conjunction with computerized image processor instead of image intensifier-TV series, thus drastically improving image quality. Initial clinical trial was made in 46 cases including intravenous digital subtraction angiography and transcatheter digital arteriography. The advantages of this method were summerized as: 1. better resolution, 2. wider field size, 3. more sophisticated image manipulation program. (author)

  16. Remote Sensing Image Fusion Based on the Combination Grey Absolute Correlation Degree and IHS Transform

    Directory of Open Access Journals (Sweden)

    Hui LIN

    2014-12-01

    Full Text Available An improved fusion algorithm for multi-source remote sensing images with high spatial resolution and multi-spectral capacity is proposed based on traditional IHS fusion and grey correlation analysis. Firstly, grey absolute correlation degree is used to discriminate non-edge pixels and edge pixels in high-spatial resolution images, by which the weight of intensity component is identified in order to combine it with high-spatial resolution image. Therefore, image fusion is achieved using IHS inverse transform. The proposed method is applied to ETM+ multi-spectral images and panchromatic image, and Quickbird’s multi-spectral images and panchromatic image respectively. The experiments prove that the fusion method proposed in the paper can efficiently preserve spectral information of the original multi-spectral images while enhancing spatial resolution greatly. By comparison and analysis, the proposed fusion algorithm is better than traditional IHS fusion and fusion method based on grey correlation analysis and IHS transform.

  17. Online Angiography Image-Based FFR Assessment During Coronary Catheterization: A Single-Center Study.

    Science.gov (United States)

    Kornowski, Ran; Vaknin-Assa, Hana; Assali, Abid; Greenberg, Gabriel; Valtzer, Orna; Lavi, Ifat

    2018-03-15

    To assess the diagnostic performance of angiography-derived fractional flow reserve (FFRangio) measurements in patients with stable coronary artery disease when used online in the catheterization laboratory during routine coronary angiography. FFR, an index of the hemodynamic severity of coronary stenosis, is derived from invasive measurements using a pressure-monitoring guidewire and hyperemic stimulus. While FFR is the gold standard, it remains under-utilized. FFRangio may have several advantages owing to the reduced operator time, no wire-related or procedural complications, and no need for administration of vasodilators. FFRangio is a novel technology that uses a patient's hemodynamic data and routine angiograms to generate FFR values at each point along the coronary tree. We present the online application of the system where FFRangio was successfully used in the catheterization laboratory during routine coronary angiography and compared to invasive FFR. Fifty-three patients (79% men) and 60 coronary lesions were analyzed. Values derived using FFRangio ranged from 0.58-0.96 and correlated closely (Pearson's correlation coefficient, r=0.91; Psystem. In this single-center experience, FFRangio values showed high correlation rates to invasive FFR.

  18. Feasibility of MR-guided angioplasty of femoral artery stenoses using real-time imaging and intraarterial contrast-enhanced MR angiography

    International Nuclear Information System (INIS)

    Paetzel, C.; Zorger, N.; Bachthaler, M.; Voelk, M.; Seitz, J.; Herold, T.; Feuerbach, S.; Lenhart, M.; Nitz, W.R.

    2004-01-01

    Purpose: To show the feasibility of magnetic resonance (MR) for guided interventional therapy of femoral and popliteal artery stenoses with commercially available materials supported by MR real-time imaging and intraarterial MR angiography. Materials and Methods: Three patients (1 female, 2 male), suffering from symptomatic arterial occlusive disease with stenoses of the femoral (n=2) or popliteal (n=1) arteries were included. Intraarterial digital subtraction angiography was performed in each patient pre- and post-interventionally as standard of reference to quantify stenoses. The degree of the stenoses reached from 71-88%. The MR images were acquired on a 1.5 T MR scanner (Magnetom Sonata; Siemens, Erlangen, Germany). For MR-angiography, a Flash 3D sequence was utilized following injection of 5 mL diluted gadodiamide (Omniscan; Amersham Buchler, Braunschweig, Germany) via the arterial access. Two maximum intensity projections (MIP) were used as road maps and localizer for the interactive positioning of a continuously running 2D-FLASH sequence with a temporal solution of 2 images per second. During the intervention, an MR compatible monitor provided the image display inside the scanner room. Safety guidelines were followed during imaging in the presence of a conductive guidewire. The lesion was crossed by a commercially available balloon catheter (Wanda, Boston Scientific; Ratingen, Germany), which was mounted on a 0.035'' guidewire (Terumo; Leuven, Belgium). The visibility was provided by radiopaque markers embedded in the balloon and was improved by injection of 1 mL gadodiamide into the balloon. After dilation, the result was checked by intraarterial MR angiography and catheter angiography. Results: The stenoses could be correctly localized by intraarterial MR angiography. There was complete correlation between intraarterial MR angiography and digital subtraction angiography. The combination of guidewire and balloon was visible and the balloon was placed

  19. Dual-energy CT of the brain: Comparison between DECT angiography-derived virtual unenhanced images and true unenhanced images in the detection of intracranial haemorrhage

    International Nuclear Information System (INIS)

    Bonatti, Matteo; Pernter, Patrizia; Bonatti, Giampietro; Lombardo, Fabio; Zamboni, Giulia A.; Pozzi Mucelli, Roberto

    2017-01-01

    To evaluate the diagnostic performance of virtual non-contrast (VNC) images in detecting intracranial haemorrhages (ICHs). Sixty-seven consecutive patients with and 67 without ICH who underwent unenhanced brain CT and DECT angiography were included. Two radiologists independently evaluated VNC and true non-contrast (TNC) images for ICH presence and type. Inter-observer agreement for VNC and TNC image evaluation was calculated. Sensitivity and specificity of VNC images for ICH detection were calculated using Fisher's exact test. VNC and TNC images were compared for ICH extent (qualitatively and quantitatively) and conspicuity assessment. On TNC images 116 different haemorrhages were detected in 67 patients. Inter-observer agreement ranged from 0.98-1.00 for TNC images and from 0.86-1.00 for VNC images. VNC sensitivity ranged from 0.90-1, according to the different ICH types, and specificity from 0.97-1. Qualitatively, ICH extent was underestimated on VNC images in 11.9% of cases. Haemorrhage volume did not show statistically significant differences between VNC and TNC images. Mean haemorrhage conspicuity was significantly lower on VNC images than on TNC images for both readers (p < 0.001). VNC images are accurate for ICH detection. Haemorrhages are less conspicuous on VNC images and their extent may be underestimated. (orig.)

  20. Dual-energy CT of the brain: Comparison between DECT angiography-derived virtual unenhanced images and true unenhanced images in the detection of intracranial haemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Bonatti, Matteo; Pernter, Patrizia; Bonatti, Giampietro [Bolzano Central Hospital, Department of Radiology, Bolzano (Italy); Lombardo, Fabio; Zamboni, Giulia A.; Pozzi Mucelli, Roberto [University of Verona, Department of Radiology, Verona (Italy)

    2017-07-15

    To evaluate the diagnostic performance of virtual non-contrast (VNC) images in detecting intracranial haemorrhages (ICHs). Sixty-seven consecutive patients with and 67 without ICH who underwent unenhanced brain CT and DECT angiography were included. Two radiologists independently evaluated VNC and true non-contrast (TNC) images for ICH presence and type. Inter-observer agreement for VNC and TNC image evaluation was calculated. Sensitivity and specificity of VNC images for ICH detection were calculated using Fisher's exact test. VNC and TNC images were compared for ICH extent (qualitatively and quantitatively) and conspicuity assessment. On TNC images 116 different haemorrhages were detected in 67 patients. Inter-observer agreement ranged from 0.98-1.00 for TNC images and from 0.86-1.00 for VNC images. VNC sensitivity ranged from 0.90-1, according to the different ICH types, and specificity from 0.97-1. Qualitatively, ICH extent was underestimated on VNC images in 11.9% of cases. Haemorrhage volume did not show statistically significant differences between VNC and TNC images. Mean haemorrhage conspicuity was significantly lower on VNC images than on TNC images for both readers (p < 0.001). VNC images are accurate for ICH detection. Haemorrhages are less conspicuous on VNC images and their extent may be underestimated. (orig.)

  1. Compressed Sensing and Low-Rank Matrix Decomposition in Multisource Images Fusion

    Directory of Open Access Journals (Sweden)

    Kan Ren

    2014-01-01

    Full Text Available We propose a novel super-resolution multisource images fusion scheme via compressive sensing and dictionary learning theory. Under the sparsity prior of images patches and the framework of the compressive sensing theory, the multisource images fusion is reduced to a signal recovery problem from the compressive measurements. Then, a set of multiscale dictionaries are learned from several groups of high-resolution sample image’s patches via a nonlinear optimization algorithm. Moreover, a new linear weights fusion rule is proposed to obtain the high-resolution image. Some experiments are taken to investigate the performance of our proposed method, and the results prove its superiority to its counterparts.

  2. Clinical assessment of SPECT/CT co-registration image fusion

    International Nuclear Information System (INIS)

    Zhou Wen; Luan Zhaosheng; Peng Yong

    2004-01-01

    Objective: Study the methodology of the SPECT/CT co-registration image fusion, and Assessment the Clinical application value. Method: 172 patients who underwent SPECT/CT image fusion during 2001-2003 were studied, 119 men, 53 women. 51 patients underwent 18FDG image +CT, 26 patients underwent 99m Tc-RBC Liver pool image +CT, 43 patients underwent 99mTc-MDP Bone image +CT, 18 patients underwent 99m Tc-MAA Lung perfusion image +CT. The machine is Millium VG SPECT of GE Company. All patients have been taken three steps image: X-ray survey, X-ray transmission and nuclear emission image (Including planer imaging, SPECT or 18 F-FDG of dual head camera) without changing the position of the patients. We reconstruct the emission image with X-ray map and do reconstruction, 18FDG with COSEM and 99mTc with OSEM. Then combine the transmission image and the reconstructed emission image. We use different process parameters in deferent image methods. The accurate rate of SPECT/CT image fusion were statistics, and compare their accurate with that of single nuclear emission image. Results: The nuclear image which have been reconstructed by X-ray attenuation and OSEM are apparent better than pre-reconstructed. The post-reconstructed emission images have no scatter lines around the organs. The outline between different issues is more clear than before. The validity of All post-reconstructed images is better than pre-reconstructed. SPECT/CT image fusion make localization have worthy bases. 138 patients, the accuracy of SPECT/CT image fusion is 91.3% (126/138), whereas 60(88.2%) were found through SPECT/CT image fusion, There are significant difference between them(P 99m Tc- RBC-SPECT +CT image fusion, but 21 of them were inspected by emission image. In BONE 99m Tc -MDP-SPECT +CT image fusion, 4 patients' removed bone(1-6 months after surgery) and their relay with normal bone had activity, their morphologic and density in CT were different from normal bones. 11 of 20 patients who could

  3. Fusion of remote sensing images based on pyramid decomposition with Baldwinian Clonal Selection Optimization

    Science.gov (United States)

    Jin, Haiyan; Xing, Bei; Wang, Lei; Wang, Yanyan

    2015-11-01

    In this paper, we put forward a novel fusion method for remote sensing images based on the contrast pyramid (CP) using the Baldwinian Clonal Selection Algorithm (BCSA), referred to as CPBCSA. Compared with classical methods based on the transform domain, the method proposed in this paper adopts an improved heuristic evolutionary algorithm, wherein the clonal selection algorithm includes Baldwinian learning. In the process of image fusion, BCSA automatically adjusts the fusion coefficients of different sub-bands decomposed by CP according to the value of the fitness function. BCSA also adaptively controls the optimal search direction of the coefficients and accelerates the convergence rate of the algorithm. Finally, the fusion images are obtained via weighted integration of the optimal fusion coefficients and CP reconstruction. Our experiments show that the proposed method outperforms existing methods in terms of both visual effect and objective evaluation criteria, and the fused images are more suitable for human visual or machine perception.

  4. The establishment of the method of three dimension volumetric fusion of emission and transmission images for PET imaging

    International Nuclear Information System (INIS)

    Zhang Xiangsong; He Zuoxiang

    2004-01-01

    Objective: To establish the method of three dimension volumetric fusion of emission and transmission images for PET imaging. Methods: The volume data of emission and transmission images acquired with Siemens ECAT HR + PET scanner were transferred to PC computer by local area network. The PET volume data were converted into 8 bit byte type, and scaled to the range of 0-255. The data coordinates of emission and transmission images were normalized by three-dimensional coordinate conversion in the same way. The images were fused with the mode of alpha-blending. The accuracy of image fusion was confirmed by its clinical application in 13 cases. Results: The three dimension volumetric fusion of emission and transmission images clearly displayed the silhouette and anatomic configuration in chest, including chest wall, lung, heart, mediastinum, et al. Forty-eight lesions in chest in 13 cases were accurately located by the image fusion. Conclusions: The volume data of emission and transmission images acquired with Siemens ECAT HR + PET scanner have the same data coordinate. The three dimension fusion software can conveniently used for the three dimension volumetric fusion of emission and transmission images, and also can correctly locate the lesions in chest

  5. Medical Image Fusion Algorithm Based on Nonlinear Approximation of Contourlet Transform and Regional Features

    Directory of Open Access Journals (Sweden)

    Hui Huang

    2017-01-01

    Full Text Available According to the pros and cons of contourlet transform and multimodality medical imaging, here we propose a novel image fusion algorithm that combines nonlinear approximation of contourlet transform with image regional features. The most important coefficient bands of the contourlet sparse matrix are retained by nonlinear approximation. Low-frequency and high-frequency regional features are also elaborated to fuse medical images. The results strongly suggested that the proposed algorithm could improve the visual effects of medical image fusion and image quality, image denoising, and enhancement.

  6. Multi-sensor radiation detection, imaging, and fusion

    Energy Technology Data Exchange (ETDEWEB)

    Vetter, Kai [Department of Nuclear Engineering, University of California, Berkeley, CA 94720 (United States); Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2016-01-01

    Glenn Knoll was one of the leaders in the field of radiation detection and measurements and shaped this field through his outstanding scientific and technical contributions, as a teacher, his personality, and his textbook. His Radiation Detection and Measurement book guided me in my studies and is now the textbook in my classes in the Department of Nuclear Engineering at UC Berkeley. In the spirit of Glenn, I will provide an overview of our activities at the Berkeley Applied Nuclear Physics program reflecting some of the breadth of radiation detection technologies and their applications ranging from fundamental studies in physics to biomedical imaging and to nuclear security. I will conclude with a discussion of our Berkeley Radwatch and Resilient Communities activities as a result of the events at the Dai-ichi nuclear power plant in Fukushima, Japan more than 4 years ago. - Highlights: • .Electron-tracking based gamma-ray momentum reconstruction. • .3D volumetric and 3D scene fusion gamma-ray imaging. • .Nuclear Street View integrates and associates nuclear radiation features with specific objects in the environment. • Institute for Resilient Communities combines science, education, and communities to minimize impact of disastrous events.

  7. Acute Solar Retinopathy Imaged With Adaptive Optics, Optical Coherence Tomography Angiography, and En Face Optical Coherence Tomography.

    Science.gov (United States)

    Wu, Chris Y; Jansen, Michael E; Andrade, Jorge; Chui, Toco Y P; Do, Anna T; Rosen, Richard B; Deobhakta, Avnish

    2018-01-01

    Solar retinopathy is a rare form of retinal injury that occurs after direct sungazing. To enhance understanding of the structural changes that occur in solar retinopathy by obtaining high-resolution in vivo en face images. Case report of a young adult woman who presented to the New York Eye and Ear Infirmary with symptoms of acute solar retinopathy after viewing the solar eclipse on August 21, 2017. Results of comprehensive ophthalmic examination and images obtained by fundus photography, microperimetry, spectral-domain optical coherence tomography (OCT), adaptive optics scanning light ophthalmoscopy, OCT angiography, and en face OCT. The patient was examined after viewing the solar eclipse. Visual acuity was 20/20 OD and 20/25 OS. The patient was left-eye dominant. Spectral-domain OCT images were consistent with mild and severe acute solar retinopathy in the right and left eye, respectively. Microperimetry was normal in the right eye but showed paracentral decreased retinal sensitivity in the left eye with a central absolute scotoma. Adaptive optics images of the right eye showed a small region of nonwaveguiding photoreceptors, while images of the left eye showed a large area of abnormal and nonwaveguiding photoreceptors. Optical coherence tomography angiography images were normal in both eyes. En face OCT images of the right eye showed a small circular hyperreflective area, with central hyporeflectivity in the outer retina of the right eye. The left eye showed a hyperreflective lesion that intensified in area from inner to middle retina and became mostly hyporeflective in the outer retina. The shape of the lesion on adaptive optics and en face OCT images of the left eye corresponded to the shape of the scotoma drawn by the patient on Amsler grid. Acute solar retinopathy can present with foveal cone photoreceptor mosaic disturbances on adaptive optics scanning light ophthalmoscopy imaging. Corresponding reflectivity changes can be seen on en face OCT, especially

  8. Extent of hypoattenuation on CT angiography source images in basilar artery occlusion: prognostic value in the Basilar Artery International Cooperation Study.

    Science.gov (United States)

    Puetz, Volker; Khomenko, Andrei; Hill, Michael D; Dzialowski, Imanuel; Michel, Patrik; Weimar, Christian; Wijman, Christine A C; Mattle, Heinrich P; Engelter, Stefan T; Muir, Keith W; Pfefferkorn, Thomas; Tanne, David; Szabo, Kristina; Kappelle, L Jaap; Algra, Ale; von Kummer, Ruediger; Demchuk, Andrew M; Schonewille, Wouter J

    2011-12-01

    The posterior circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS) quantifies the extent of early ischemic changes in the posterior circulation with a 10-point grading system. We hypothesized that pc-ASPECTS applied to CT angiography source images predicts functional outcome of patients in the Basilar Artery International Cooperation Study (BASICS). BASICS was a prospective, observational registry of consecutive patients with acute symptomatic basilar artery occlusion. Functional outcome was assessed at 1 month. We applied pc-ASPECTS to CT angiography source images of patients with CT angiography for confirmation of basilar artery occlusion. We calculated unadjusted and adjusted risk ratios (RRs) of pc-ASPECTS dichotomized at ≥8 versus <8. Primary outcome measure was favorable outcome (modified Rankin Scale scores 0-3). Secondary outcome measures were mortality and functional independence (modified Rankin Scale scores 0-2). Of 158 patients included, 78 patients had a CT angiography source images pc-ASPECTS≥8. Patients with a pc-ASPECTS≥8 more often had a favorable outcome than patients with a pc-ASPECTS<8 (crude RR, 1.7; 95% CI, 0.98-3.0). After adjustment for age, baseline National Institutes of Health Stroke Scale score, and thrombolysis, pc-ASPECTS≥8 was not related to favorable outcome (RR, 1.3; 95% CI, 0.8-2.2), but it was related to reduced mortality (RR, 0.7; 95% CI, 0.5-0.98) and functional independence (RR, 2.0; 95% CI, 1.1-3.8). In post hoc analysis, pc-ASPECTS dichotomized at ≥6 versus <6 predicted a favorable outcome (adjusted RR, 3.1; 95% CI, 1.2-7.5). pc-ASPECTS on CT angiography source images independently predicted death and functional independence at 1 month in the CT angiography subgroup of patients in the BASICS registry.

  9. Multi-Modality Medical Image Fusion Based on Wavelet Analysis and Quality Evaluation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Multi-modality medical image fusion has more and more important applications in medical image analysisand understanding. In this paper, we develop and apply a multi-resolution method based on wavelet pyramid to fusemedical images from different modalities such as PET-MRI and CT-MRI. In particular, we evaluate the different fusionresults when applying different selection rules and obtain optimum combination of fusion parameters.

  10. Evolution of Choroidal Neovascularization due to Presumed Ocular Histoplasmosis Syndrome on Multimodal Imaging including Optical Coherence Tomography Angiography

    Directory of Open Access Journals (Sweden)

    T. Y. Alvin Liu

    2018-01-01

    Full Text Available A 37-year-old Caucasian woman presented with acute decrease in central vision in her right eye and was found to have subfoveal choroidal neovascularization (CNV due to presumed ocular histoplasmosis syndrome (POHS. Her visual acuity improved from 20/70 to 20/20 at her 6-month follow-up, after 3 consecutive monthly intravitreal bevacizumab injections were initiated at her first visit. Although no CNV activity was seen on fluorescein angiography (FA or spectral-domain optical coherence tomography (SD-OCT at her 2-month, 4-month, and 6-month follow-up visits, persistent flow in the CNV lesion was detected on optical coherence tomography angiography (OCTA. OCTA shows persistent vascular flow as well as changes in vascular flow in CNV lesions associated with POHS, indicating the continued presence of patent vessels and changes in these CNV lesions, even when traditional imaging of the lesion with OCT and FA indicates stability of the lesion with no disease activity. Additional cases with longitudinal follow-up are needed to assess how OCTA should be incorporated into clinical practice.

  11. Multispectral medical image fusion in Contourlet domain for computer based diagnosis of Alzheimer’s disease

    International Nuclear Information System (INIS)

    Bhateja, Vikrant; Moin, Aisha; Srivastava, Anuja; Bao, Le Nguyen; Lay-Ekuakille, Aimé; Le, Dac-Nhuong

    2016-01-01

    Computer based diagnosis of Alzheimer’s disease can be performed by dint of the analysis of the functional and structural changes in the brain. Multispectral image fusion deliberates upon fusion of the complementary information while discarding the surplus information to achieve a solitary image which encloses both spatial and spectral details. This paper presents a Non-Sub-sampled Contourlet Transform (NSCT) based multispectral image fusion model for computer-aided diagnosis of Alzheimer’s disease. The proposed fusion methodology involves color transformation of the input multispectral image. The multispectral image in YIQ color space is decomposed using NSCT followed by dimensionality reduction using modified Principal Component Analysis algorithm on the low frequency coefficients. Further, the high frequency coefficients are enhanced using non-linear enhancement function. Two different fusion rules are then applied to the low-pass and high-pass sub-bands: Phase congruency is applied to low frequency coefficients and a combination of directive contrast and normalized Shannon entropy is applied to high frequency coefficients. The superiority of the fusion response is depicted by the comparisons made with the other state-of-the-art fusion approaches (in terms of various fusion metrics).

  12. Multispectral medical image fusion in Contourlet domain for computer based diagnosis of Alzheimer’s disease

    Energy Technology Data Exchange (ETDEWEB)

    Bhateja, Vikrant, E-mail: bhateja.vikrant@gmail.com, E-mail: nhuongld@hus.edu.vn; Moin, Aisha; Srivastava, Anuja [Shri Ramswaroop Memorial Group of Professional Colleges (SRMGPC), Lucknow, Uttar Pradesh 226028 (India); Bao, Le Nguyen [Duytan University, Danang 550000 (Viet Nam); Lay-Ekuakille, Aimé [Department of Innovation Engineering, University of Salento, Lecce 73100 (Italy); Le, Dac-Nhuong, E-mail: bhateja.vikrant@gmail.com, E-mail: nhuongld@hus.edu.vn [Duytan University, Danang 550000 (Viet Nam); Haiphong University, Haiphong 180000 (Viet Nam)

    2016-07-15

    Computer based diagnosis of Alzheimer’s disease can be performed by dint of the analysis of the functional and structural changes in the brain. Multispectral image fusion deliberates upon fusion of the complementary information while discarding the surplus information to achieve a solitary image which encloses both spatial and spectral details. This paper presents a Non-Sub-sampled Contourlet Transform (NSCT) based multispectral image fusion model for computer-aided diagnosis of Alzheimer’s disease. The proposed fusion methodology involves color transformation of the input multispectral image. The multispectral image in YIQ color space is decomposed using NSCT followed by dimensionality reduction using modified Principal Component Analysis algorithm on the low frequency coefficients. Further, the high frequency coefficients are enhanced using non-linear enhancement function. Two different fusion rules are then applied to the low-pass and high-pass sub-bands: Phase congruency is applied to low frequency coefficients and a combination of directive contrast and normalized Shannon entropy is applied to high frequency coefficients. The superiority of the fusion response is depicted by the comparisons made with the other state-of-the-art fusion approaches (in terms of various fusion metrics).

  13. Ultrasound and PET-CT image fusion for prostate brachytherapy image guidance

    International Nuclear Information System (INIS)

    Hasford, F.

    2015-01-01

    Fusion of medical images between different cross-sectional modalities is widely used, mostly where functional images are fused with anatomical data. Ultrasound has for some time now been the standard imaging technique used for treatment planning of prostate cancer cases. While this approach is laudable and has yielded some positive results, latest developments have been the integration of images from ultrasound and other modalities such as PET-CT to compliment missing properties of ultrasound images. This study has sought to enhance diagnosis and treatment of prostate cancers by developing MATLAB algorithms to fuse ultrasound and PET-CT images. The fused ultrasound-PET-CT image has shown to contain improved quality of information than the individual input images. The fused image has the property of reduced uncertainty, increased reliability, robust system performance, and compact representation of information. The objective of co-registering the ultrasound and PET-CT images was achieved by conducting performance evaluation of the ultrasound and PET-CT imaging systems, developing image contrast enhancement algorithm, developing MATLAB image fusion algorithm, and assessing accuracy of the fusion algorithm. Performance evaluation of the ultrasound brachytherapy system produced satisfactory results in accordance with set tolerances as recommended by AAPM TG 128. Using an ultrasound brachytherapy quality assurance phantom, average axial distance measurement of 10.11 ± 0.11 mm was estimated. Average lateral distance measurements of 10.08 ± 0.07 mm, 20.01 ± 0.06 mm, 29.89 ± 0.03 mm and 39.84 ± 0.37 mm were estimated for the inter-target distances corresponding to 10 mm, 20 mm, 30 mm and 40 mm respectively. Volume accuracy assessment produced measurements of 3.97 cm 3 , 8.86 cm 3 and 20.11 cm 3 for known standard volumes of 4 cm 3 , 9 cm 3 and 20 cm 3 respectively. Depth of penetration assessment of the ultrasound system produced an estimate of 5.37 ± 0.02 cm

  14. Dual-energy CT of the brain: Comparison between DECT angiography-derived virtual unenhanced images and true unenhanced images in the detection of intracranial haemorrhage.

    Science.gov (United States)

    Bonatti, Matteo; Lombardo, Fabio; Zamboni, Giulia A; Pernter, Patrizia; Pozzi Mucelli, Roberto; Bonatti, Giampietro

    2017-07-01

    To evaluate the diagnostic performance of virtual non-contrast (VNC) images in detecting intracranial haemorrhages (ICHs). Sixty-seven consecutive patients with and 67 without ICH who underwent unenhanced brain CT and DECT angiography were included. Two radiologists independently evaluated VNC and true non-contrast (TNC) images for ICH presence and type. Inter-observer agreement for VNC and TNC image evaluation was calculated. Sensitivity and specificity of VNC images for ICH detection were calculated using Fisher's exact test. VNC and TNC images were compared for ICH extent (qualitatively and quantitatively) and conspicuity assessment. On TNC images 116 different haemorrhages were detected in 67 patients. Inter-observer agreement ranged from 0.98-1.00 for TNC images and from 0.86-1.00 for VNC images. VNC sensitivity ranged from 0.90-1, according to the different ICH types, and specificity from 0.97-1. Qualitatively, ICH extent was underestimated on VNC images in 11.9% of cases. Haemorrhage volume did not show statistically significant differences between VNC and TNC images. Mean haemorrhage conspicuity was significantly lower on VNC images than on TNC images for both readers (p < 0.001). VNC images are accurate for ICH detection. Haemorrhages are less conspicuous on VNC images and their extent may be underestimated. • VNC images represent a reproducible tool for detecting ICH. • ICH can be identified on VNC images with high sensitivity and specificity. • Intracranial haemorrhages are less conspicuous on VNC images than on TNC images. • Intracranial haemorrhages extent may be underestimated on VNC images.

  15. Two-dimensional fusion imaging of planar bone scintigraphy and radiographs in patients with clinical scaphoid fracture: an imaging study

    DEFF Research Database (Denmark)

    Henriksen, Otto Mølby; Lonsdale, Markus Georg; Jensen, T D

    2009-01-01

    . Bone scintigraphy is highly sensitive for the detection of fractures, but exact localization of scintigraphic lesions may be difficult and can negatively affect diagnostic accuracy. PURPOSE: To investigate the influence of image fusion of planar bone scintigraphy and radiographs on image interpretation......BACKGROUND: Although magnetic resonance imaging (MRI) is now considered the gold standard in second-line imaging of patients with suspected scaphoid fracture and negative radiographs, bone scintigraphy can be used in patients with pacemakers, metallic implants, or other contraindications to MRI....... CONCLUSION: Image fusion of planar bone scintigrams and radiographs has a significant influence on image interpretation and increases both diagnostic confidence and interobserver agreement....

  16. Percutaneous Thermal Ablation with Ultrasound Guidance. Fusion Imaging Guidance to Improve Conspicuity of Liver Metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Hakime, Antoine, E-mail: thakime@yahoo.com; Yevich, Steven; Tselikas, Lambros; Deschamps, Frederic [Gustave Roussy - Cancer Campus, Interventional Radiology Department (France); Petrover, David [Imagerie Médicale Paris Centre, IMPC (France); Baere, Thierry De [Gustave Roussy - Cancer Campus, Interventional Radiology Department (France)

    2017-05-15

    PurposeTo assess whether fusion imaging-guided percutaneous microwave ablation (MWA) can improve visibility and targeting of liver metastasis that were deemed inconspicuous on ultrasound (US).Materials and MethodsMWA of liver metastasis not judged conspicuous enough on US was performed under CT/US fusion imaging guidance. The conspicuity before and after the fusion imaging was graded on a five-point scale, and significance was assessed by Wilcoxon test. Technical success, procedure time, and procedure-related complications were evaluated.ResultsA total of 35 patients with 40 liver metastases (mean size 1.3 ± 0.4 cm) were enrolled. Image fusion improved conspicuity sufficiently to allow fusion-targeted MWA in 33 patients. The time required for image fusion processing and tumors’ identification averaged 10 ± 2.1 min (range 5–14). Initial conspicuity on US by inclusion criteria was 1.2 ± 0.4 (range 0–2), while conspicuity after localization on fusion imaging was 3.5 ± 1 (range 1–5, p < 0.001). Technical success rate was 83% (33/40) in intention-to-treat analysis and 100% in analysis of treated tumors. There were no major procedure-related complications.ConclusionsFusion imaging broadens the scope of US-guided MWA to metastasis lacking adequate conspicuity on conventional US. Fusion imaging is an effective tool to increase the conspicuity of liver metastases that were initially deemed non visualizable on conventional US imaging.

  17. Functional and morphological imaging of thyroid associated eye disease. Data evaluation by means of image fusion

    International Nuclear Information System (INIS)

    Kainz, H.

    2002-08-01

    Aim: to recognize the structures that show an uptake of a 99mTc-labeled octreotide tracer within the orbit and head in patients with thyroid associated eye disease relying on image fusion. Methods: A series of 18 patients presenting the signs and symptoms of thyroid associated eye disease were studied. Functional imaging was done with 99mTc-HYNIC-TOC, a newly in-house developed tracer. Both whole body as well as single photon emission tomographies (SPECT) of the head were obtained in each patient. Parallel to nuclear medicine imaging, morphological imaging was done using either computed tomography or magnetic resonance. Results: By means of image fusion farther more information on the functional status of the patients was obtained. All areas showing an uptake could be anatomically identified, revealing a series of organs that had not yet been consideren in this disease. The organs presenting tracer uptake showed characteristic forms as described below: - eye glass sign: lacrimal gland and lacrimal ducts - scissors sign: eye muscles, rectus sup. and inf. - arch on CT: muscle displacement - Omega sign: tonsils and salivary glands - W- sign: tonsils and salivary glands Conclusions: By means of image fusion it was possible to recognize that a series of organs of the neck and head express somatostatin receptors. We interpret these results as a sign of inflammation of the lacrimal glands, the lacrimal ducts, the cervical lymphatics, the anterior portions of the extra ocular eye muscles and muscles of the posterior cervical region. Somatostatin uptake in these sturctures reflects the prescence of specific receptors which reflect the immuno regulating function of the peptide. (author)

  18. Image fusion using MIM software via picture archiving and communication system

    International Nuclear Information System (INIS)

    Gu Zhaoxiang; Jiang Maosong

    2001-01-01

    The preliminary studies of the multimodality image registration and fusion were performed using an image fusion software and a picture archiving and communication system (PACS) to explore the methodology. Original image voluminal data were acquired with a CT scanner, MR and dual-head coincidence SPECT, respectively. The data sets from all imaging devices were queried, retrieved, transferred and accessed via DICOM PACS. The image fusion was performed at the SPECT ICON work-station, where the MIM (Medical Image Merge) fusion software was installed. The images were created by re-slicing original volume on the fly. The image volumes were aligned by translation and rotation of these view ports with respect to the original volume orientation. The transparency factor and contrast were adjusted in order that both volumes can be visualized in the merged images. The image volume data of CT, MR and nuclear medicine were transferred, accessed and loaded via PACS successfully. The perfect fused images of chest CT/ 18 F-FDG and brain MR/SPECT were obtained. These results showed that image fusion technique using PACS was feasible and practical. Further experimentation and larger validation studies were needed to explore the full potential of the clinical use

  19. Development of a novel fusion imaging technique in the diagnosis of hepatobiliary-pancreatic lesions

    International Nuclear Information System (INIS)

    Soga, Koichi; Ochiai, Jun; Miyajima, Takashi; Kassai, Kyoichi; Itani, Kenji; Yagi, Nobuaki; Naito, Yuji

    2013-01-01

    Multi-row detector computed tomography (MDCT) and magnetic resonance cholangiopancreatography (MRCP) play an important role in the imaging diagnosis of hepatobiliary-pancreatic lesions. Here we investigated whether unifying the MDCT and MRCP images onto the same screen using fusion imaging could overcome the limitations of each technique, while still maintaining their benefits. Moreover, because reports of fusion imaging using MDCT and MRCP are rare, we assessed the benefits and limitations of this method for its potential application in a clinical setting. The patient group included 9 men and 11 women. Among the 20 patients, the final diagnoses were as follows: 10 intraductal papillary mucinous neoplasms, 5 biliary system carcinomas, 1 pancreatic adenocarcinoma and 5 non-neoplastic lesions. After transmitting the Digital Imaging and Communication in Medicine data of the MDCT and MRCP images to a workstation, we performed a 3-D organisation of both sets of images using volume rendering for the image fusion. Fusion imaging enabled clear identification of the spatial relationship between a hepatobiliary-pancreatic lesion and the solid viscera and/or vessels. Further, this method facilitated the determination of the relationship between the anatomical position of the lesion and its surroundings more easily than either MDCT or MRCP alone. Fusion imaging is an easy technique to perform and may be a useful tool for planning treatment strategies and for examining pathological changes in hepatobiliary-pancreatic lesions. Additionally, the ease of obtaining the 3-D images suggests the possibility of using these images to plan intervention strategies.

  20. Adaptive polarization image fusion based on regional energy dynamic weighted average

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yong-qiang; PAN Quan; ZHANG Hong-cai

    2005-01-01

    According to the principle of polarization imaging and the relation between Stokes parameters and the degree of linear polarization, there are much redundant and complementary information in polarized images. Since man-made objects and natural objects can be easily distinguished in images of degree of linear polarization and images of Stokes parameters contain rich detailed information of the scene, the clutters in the images can be removed efficiently while the detailed information can be maintained by combining these images. An algorithm of adaptive polarization image fusion based on regional energy dynamic weighted average is proposed in this paper to combine these images. Through an experiment and simulations,most clutters are removed by this algorithm. The fusion method is used for different light conditions in simulation, and the influence of lighting conditions on the fusion results is analyzed.

  1. Fusion method of SAR and optical images for urban object extraction

    Science.gov (United States)

    Jia, Yonghong; Blum, Rick S.; Li, Fangfang

    2007-11-01

    A new image fusion method of SAR, Panchromatic (Pan) and multispectral (MS) data is proposed. First of all, SAR texture is extracted by ratioing the despeckled SAR image to its low pass approximation, and is used to modulate high pass details extracted from the available Pan image by means of the á trous wavelet decomposition. Then, high pass details modulated with the texture is applied to obtain the fusion product by HPFM (High pass Filter-based Modulation) fusion method. A set of image data including co-registered Landsat TM, ENVISAT SAR and SPOT Pan is used for the experiment. The results demonstrate accurate spectral preservation on vegetated regions, bare soil, and also on textured areas (buildings and road network) where SAR texture information enhances the fusion product, and the proposed approach is effective for image interpret and classification.

  2. Pancreatic adenocarcinoma: combination of MR imaging, MR angiography and MR cholangiopancreatography for the diagnosis and assessment of resectability

    International Nuclear Information System (INIS)

    Catalano, C.; Pavone, P.; Laghi, A.; Panebianco, V.; Scipioni, A.; Fanelli, F.; Brillo, R.; Passariello, R.

    1998-01-01

    The purpose of this study was to determine the possibility of integrating MR cholangiopancreatography (MRCP) and MR angiography (MRA) to conventional MR images in the diagnosis and assessment of resectability of pancreatic adenocarcinoma. Twenty-three patients with pancreatic adenocarcinoma were prospectively examined with MR. Conventional MR images were acquired in all patients. Three-dimensional MRCP and MRA images were acquired in all patients with suspected biliary and vascular involvement. Acquisition time was less than 45 min in all cases. Images were independently evaluated by two radiologists, with final reading decided by consensus among readers. Diagnosis was confirmed with surgery in 16 patients and with percutaneous biopsy in 7. Concordance among readers was high with a kappa value of 0.83. Pancreatic adenocarcinoma was observed in all patients. Correct assessment of unresectability due to vascular involvement was found in 22 of 23 patients. Biliary obstruction was evident in 13 patients, involving the biliary and pancreatic ducts in 9 and the biliary ducts only in 4. Technical advances permit extensive use of MRI in the evaluation of abdominal pathologies. The combination of MR imaging, MRCP, and MRA can provide sufficient information for the diagnosis and assessment of resectability of pancreatic adenocarcinoma, which otherwise would require three different exams. (orig.)

  3. Imaging quality and effective radiation dose of prospective ECG-gated axial multidetector row computed tomography coronary angiography

    International Nuclear Information System (INIS)

    Capunay, C.; Carrascosa, P.; Vallejos, J.; Deviggiano, A.; Pollono, P.M.; Garcia, M.J.

    2011-01-01

    Objective. To determine the imaging quality and effective radiation dose (ERD) of prospective ECG-gated multidetector row computed tomography coronary angiography (PMDCTCA) compared to retrospective ECG-gating (RMDCT-CA). Materials and Methods. Forty-five PMDCT-CA scans were retrospectively reviewed for assessing imaging quality and ERD, and compared to 90 RMDCT-CA scans performed with (n=45) and without (n=45) tube current modulation, selected from our database on the basis of similar demographical characteristics. ERD was compared between all three groups. Imaging quality was assessed by two independent observers and compared to the imaging quality of the group of RMDCT-CA scans performed with tube current modulation. The interobserver variability was also determined. Results. There were no significant differences in imaging quality between the two groups. Interobserver variability was k=0.92 (95 % CI: 0.87-0.96). The ERD (mean ± SD) using PMDCT-CA was 2.88 ± 0.37 mSv compared to 10.50 ± 1.15 mSv (p [es

  4. Detection of hypoxic-ischemic brain injury with 3D-enhanced T2* weighted angiography (ESWAN) imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gang, QiangQiang, E-mail: rousikang@163.com; Zhang, Jianing, E-mail: 1325916060@qq.com; Hao, Peng, E-mail: 1043600590@qq.com; Xu, Yikai, E-mail: yikaivip@163.com

    2013-11-01

    Objective: To demonstrate the use of 3D-enhanced T2* weighted angiography (ESWAN) imaging for the observation and quantification of the evolution of brain injury induced by a recently developed model of hypoxic-ischemic brain injury (HI/R) in neonatal piglets. Methods: For these experiments, newborn piglets were subjected to HI/R injury, during which ESWAN scanning was performed, followed by H and E staining and immunohistochemistry of AQP-4 expression. Results: In the striatum, values from T2* weighted magnetic resonance imaging (MRI) increased and reached their highest level at 3 days post injury, whereas T2* values increased and peaked at 24 h in the subcortical region. The change in T2* values was concordant with brain edema. Phase values in the subcortical border region were not dependent on time post-injury. Magnitude values were significantly different from the control group, and increased gradually over time in the subcortical border region. Susceptibility-weighted images (SWI) indicated small petechial hemorrhages in the striatum and thalamus, as well as dilated intramedullary veins. Conclusion: SWI images can be used to detect white and gray matter microhemorrhages and dilated intramedullary veins. The T2*, phase, and magnitude map can also reflect the development of brain injury. Our data illustrate that ESWAN imaging can increase the diagnostic sensitivity and specificity of MRI in neonatal hypoxic-ischemic encephalopathy.

  5. Detection of hypoxic-ischemic brain injury with 3D-enhanced T2* weighted angiography (ESWAN) imaging

    International Nuclear Information System (INIS)

    Gang, QiangQiang; Zhang, Jianing; Hao, Peng; Xu, Yikai

    2013-01-01

    Objective: To demonstrate the use of 3D-enhanced T2* weighted angiography (ESWAN) imaging for the observation and quantification of the evolution of brain injury induced by a recently developed model of hypoxic-ischemic brain injury (HI/R) in neonatal piglets. Methods: For these experiments, newborn piglets were subjected to HI/R injury, during which ESWAN scanning was performed, followed by H and E staining and immunohistochemistry of AQP-4 expression. Results: In the striatum, values from T2* weighted magnetic resonance imaging (MRI) increased and reached their highest level at 3 days post injury, whereas T2* values increased and peaked at 24 h in the subcortical region. The change in T2* values was concordant with brain edema. Phase values in the subcortical border region were not dependent on time post-injury. Magnitude values were significantly different from the control group, and increased gradually over time in the subcortical border region. Susceptibility-weighted images (SWI) indicated small petechial hemorrhages in the striatum and thalamus, as well as dilated intramedullary veins. Conclusion: SWI images can be used to detect white and gray matter microhemorrhages and dilated intramedullary veins. The T2*, phase, and magnitude map can also reflect the development of brain injury. Our data illustrate that ESWAN imaging can increase the diagnostic sensitivity and specificity of MRI in neonatal hypoxic-ischemic encephalopathy

  6. Catheter Angiography

    Medline Plus

    Full Text Available ... further information please consult the ACR Manual on Contrast Media and its references. The risk of serious allergic ... View full size with caption Related Articles and Media Angioplasty and Vascular Stenting MR Angiography (MRA) Contrast Materials CT Angiography (CTA) X-ray, Interventional Radiology ...

  7. Functional Imaging of the Foot with Perfusion Angiography in Critical Limb Ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Reekers, Jim A., E-mail: j.a.reekers@amc.uva.nl [AMC, Dept of Radiology (Netherlands); Koelemay, Mark J. W., E-mail: m.j.koelemaij@amc.uva.nl [AMC, Dept of Vascular Surgery (Netherlands); Marquering, Henk A., E-mail: h.a.marquering@amc.uva.nl; Bavel, Ed T. van, E-mail: e.vanbavel@amc.uva.n [AMC, Dept of Biomedical Engineering and Physics (Netherlands)

    2016-02-15

    PurposeTo report on the first clinical experience with perfusion angiography (PA) of the foot in patients with chronic critical limb ischemia.Materials and MethodsPA is a post-processing software algorithm and no extra digital subtraction angiography (DSA) has to be performed for this analysis. The data used to test the feasibility of PA were obtained from a consecutive group of 89 patients with CLI who were treated with standard below the knee angioplasty and 12 separate patients who were not suitable for endovascular revascularization.ResultsMotion artifacts in the dataset of the DSA made post-procedural analysis impossible in 10 % intervention. In the majority of patients (59/68) PA showed an increase in volume flow in the foot after successful angioplasty of the crural vessels. However, in 9/68 patients no increase was seen after successful angioplasty. With the use of a local administered competitive α-adrenergic receptor antagonist, it is also possible to test and quantify the capillary resistance index which is a parameter for the remaining functionality of the microcirculation in CLI patients.ConclusionPA might be used as a new endpoint for lower limb revascularization and can also be used to test the functionality the microcirculation to identify sub-types of patients with CLI. Clinical evaluation and standardization of PA is mandatory before introduction in daily practice.

  8. Extended feature-fusion guidelines to improve image-based multi-modal biometrics

    CSIR Research Space (South Africa)

    Brown, Dane

    2016-09-01

    Full Text Available The feature-level, unlike the match score-level, lacks multi-modal fusion guidelines. This work demonstrates a practical approach for improved image-based biometric feature-fusion. The approach extracts and combines the face, fingerprint...

  9. Advanced image-based virtual monoenergetic dual-energy CT angiography of the abdomen: optimization of kiloelectron volt settings to improve image contrast

    International Nuclear Information System (INIS)

    Albrecht, Moritz H.; Scholtz, Jan-Erik; Huesers, Kristina; Beeres, Martin; Bucher, Andreas M.; Kaup, Moritz; Martin, Simon S.; Fischer, Sebastian; Bodelle, Boris; Bauer, Ralf W.; Lehnert, Thomas; Vogl, Thomas J.; Wichmann, Julian L.

    2016-01-01

    To compare quantitative image quality parameters in abdominal dual-energy computed tomography angiography (DE-CTA) using an advanced image-based (Mono+) reconstruction algorithm for virtual monoenergetic imaging and standard DE-CTA. Fifty-five patients (36 men; mean age, 64.2 ± 12.7 years) who underwent abdominal DE-CTA were retrospectively included. Mono + images were reconstructed at 40, 50, 60, 70, 80, 90 and 100 keV levels and as standard linearly blended M 0 .6 images (60 % 100 kV, 40 % 140 kV). The contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) of the common hepatic (CHA), splenic (SA), superior mesenteric (SMA) and left renal arteries (LRA) were objectively measured. Mono+ DE-CTA series showed a statistically superior CNR for 40, 50, 60, 70 and 80 keV (P < 0.031) compared to M 0 .6 images for all investigated arteries except SMA at 80 keV (P = 0.08). CNR at 40 keV revealed a mean relative increase of 287.7 % compared to linearly blended images among all assessed arteries (P < 0.001). SNR of Mono+ images was consistently significantly higher at 40, 50, 60 and 70 keV compared to M 0 .6 for CHA and SA (P < 0.009). Compared to linearly blended images, Mono+ reconstructions at low keV levels of abdominal DE-CTA datasets significantly improve quantitative image quality. (orig.)

  10. Pediatric CT angiography

    International Nuclear Information System (INIS)

    Siegel, M.J.

    2005-01-01

    Advances in CT technology are having profound impact on imaging children and have made CT angiography possible even in neonates. Even with the tiny anatomy of neonates, small volumes of contrast material, and small venous access catheters, successful CT angiography can be performed with attention to detail. Meticulous attention to patient preparation, the proper selection of technical factors, and optimal delivery of contrast material are crucial. Data post-processing and the creation of 3-D reconstructions are also essential in establishing a correct diagnosis. The applications fo CT angiography are different in children than in adults and most applications in children involve assessment of congenital and postoperative vascular and cardiac diseases. The use of CT angiography offers the opportunity to eliminate the long periods of sedation associated with MR and reduce the radiation exposure associated with conventional angiography. Generally, the benefits of CT angiography in children outweigh the risk, namely that of radiation exposure. However, care must still be taken to minimize the radiation exposure. (orig.)

  11. Fusion of SPECT/TC images: Usefulness and benefits in degenerative spinal cord pathology

    International Nuclear Information System (INIS)

    Ocampo, Monica; Ucros, Gonzalo; Bermudez, Sonia; Morillo, Anibal; Rodriguez, Andres

    2005-01-01

    The objectives are to compare CT and SPECT bone scintigraphy evaluated independently with SPECT-CT fusion images in patients with known degenerative spinal pathology. To demonstrate the clinical usefulness of CT and SPECT fusion images. Materials and methods: Thirty-one patients with suspected degenerative spinal disease were evaluated with thin-slice, non-angled helical CT and bone scintigrams with single photon emission computed tomography (SPECT), both with multiplanar reconstructions within a 24-hour period After independent evaluation by a nuclear medicine specialist and a radiologist, multimodality image fusion software was used to merge the CT and SPECT studies and a final consensus interpretation of the combined images was obtained. Results: Thirty-two SPECT bone scintigraphy images, helical CT studies and SPECT-CT fusion images were obtained for 31 patients with degenerative spinal disease. The results of the bone scintigraphy and CT scans were in agreement in 17 pairs of studies (53.12%). In these studies image fusion did not provide additional information on the location or extension of the lesions. In 11 of the study pairs (34.2%), the information obtained was not in agreement between scintigraphy and CT studies: CT images demonstrated several abnormalities, whereas the SPECT images showed only one dominant lesion, or the SPECT images did not provide enough information for anatomical localization. In these cases image fusion helped establish the precise localization of the most clinically significant lesion, which matched the lesion with the greatest uptake. In 4 studies (12.5%) the CT and SPECT images were not in agreement: CT and SPECT images showed different information (normal scintigraphy, abnormal CT), thus leading to inconclusive fusion images. Conclusion: The use of CT-SPECT fusion images in degenerative spinal disease allows for the integration of anatomic detail with physiologic and functional information. CT-SPECT fusion improves the

  12. MR angiography of stenosis and aneurysm models in the pulsatile flow: variation with imaging parameters and concentration of contrast media

    International Nuclear Information System (INIS)

    Park, Kyung Joo; Park, Jae Hyung; Lee, Hak Jong; Won, Hyung Jin; Lee, Dong Hyuk; Min, Byung Goo; Chang, Kee Hyun

    1997-01-01

    The image quality of magnetic resonance angiography (MRA) varies according to the imaging techniques applied and the parameters affected by blood flow patterns, as well as by the shape of the blood vessels. This study was designed to assess the influence on signal intensity and its distribution of the geometry of these vessels, the imaging parameters, and the concentration of contrast media in MRA of stenosis and aneurysm models. MRA was performed in stenosis and aneurysm models made of glass tubes, using pulsatile flow with viscosity and flow profile similar to those of blood. Slice and maximum intensity projection (MIP) images were obtained using various imaging techniques and parameters;there was variation in repetition time, flip angle, imaging planes, and concentrations of contrast media. On slice images of three-dimensional (3D) time-of-flight (TOF) techniques, flow signal intensity was measured at five locations in the models, and contrast ratio was calculated as the difference between flow signal intensity (SI) and background signal intensity (SIb) divided by background signal intensity or (SI-SIb)/SIb. MIP images obtained by various techniques and using various parameters were also analyzed, with emphasis in the stenosis model on demonstrated degree of stenosis, severity of signal void and image distortion, and in the aneurysm model, on degree of visualization, distortion of contour and distribution of signals. In 3D TOF, the shortest TR (36 msec) and the largest FA (50 deg ) resulted in the highest contrast ratio, but larger flip angles did not effectively demonstrate the demonstration of the peripheral part of the aneurysm. Loss of signal was most prominent in images of the stenosis model obtained with parallel or oblique planes to the flow direction. The two-dimensional TOF technique also caused signal void in stenosis, but precisely demonstrated the aneurysm, with dense opacification of the peripheral part. The phase contrast technique showed some

  13. Magnetic resonance angiography in infrapopliteal arterial disease: prospective comparison of 1.5 and 3 Tesla magnetic resonance imaging.

    Science.gov (United States)

    Diehm, Nicolas; Kickuth, Ralph; Baumgartner, Iris; Srivastav, Sudesh K; Gretener, Silvia; Husmann, Marc J; Jaccard, Yves; Do, Do Dai; Triller, Juergen; Bonel, Harald M

    2007-06-01

    To prospectively determine the accuracy of 1.5 Tesla (T) and 3 T magnetic resonance angiography (MRA) versus digital subtraction angiography (DSA) in the depiction of infrageniculate arteries in patients with symptomatic peripheral arterial disease. A prospective 1.5 T, 3 T MRA, and DSA comparison was used to evaluate 360 vessel segments in 10 patients (15 limbs) with chronic symptomatic peripheral arterial disease. Selective DSA was performed within 30 days before both MRAs. The accuracy of 1.5 T and 3 T MRA was compared with DSA as the standard of reference by consensus agreement of 2 experienced readers. Signal-to-noise ratios (SNR) and signal-difference-to-noise ratios (SDNRs) were quantified. No significant difference in overall image quality, sufficiency for diagnosis, depiction of arterial anatomy, motion artifacts, and venous overlap was found comparing 1.5 T with 3 T MRA (P > 0.05 by Wilcoxon signed rank and as by Cohen k test). Overall sensitivity of 1.5 and 3 T MRA for detection of significant arterial stenosis was 79% and 82%, and specificity was 87% and 87% for both modalities, respectively. Interobserver agreement was excellent k > 0.8, P < 0.05) for 1.5 T as well as for 3 T MRA. SNR and SDNR were significantly increased using the 3 T system (average increase: 36.5%, P < 0.032 by t test, and 38.5%, P < 0.037 respectively). Despite marked improvement of SDNR, 3 T MRA does not yet provide a significantly higher accuracy in diagnostic imaging of atherosclerotic lesions below the knee joint as compared with 1.5 T MRA.

  14. Fusion of infrared and visible images based on BEMD and NSDFB

    Science.gov (United States)

    Zhu, Pan; Huang, Zhanhua; Lei, Hai

    2016-07-01

    This paper presents a new fusion method based on the adaptive multi-scale decomposition of bidimensional empirical mode decomposition (BEMD) and the flexible directional expansion of nonsubsampled directional filter banks (NSDFB) for visible-infrared images. Compared with conventional multi-scale fusion methods, BEMD is non-parametric and completely data-driven, which is relatively more suitable for non-linear signals decomposition and fusion. NSDFB can provide direction filtering on the decomposition levels to capture more geometrical structure of the source images effectively. In our fusion framework, the entropies of the two patterns of source images are firstly calculated and the residue of the image whose entropy is larger is extracted to make it highly relevant with the other source image. Then, the residue and the other source image are decomposed into low-frequency sub-bands and a sequence of high-frequency directional sub-bands in different scales by using BEMD and NSDFB. In this fusion scheme, two relevant fusion rules are used in low-frequency sub-bands and high-frequency directional sub-bands, respectively. Finally, the fused image is obtained by applying corresponding inverse transform. Experimental results indicate that the proposed fusion algorithm can obtain state-of-the-art performance for visible-infrared images fusion in both aspects of objective assessment and subjective visual quality even for the source images obtained in different conditions. Furthermore, the fused results have high contrast, remarkable target information and rich details information that are more suitable for human visual characteristics or machine perception.

  15. Induced renal artery stenosis in rabbits: magnetic resonance imaging, angiography, and radionuclide determination of blood volume and blood flow

    International Nuclear Information System (INIS)

    Mitchell, D.G.; Tobin, M.; LeVeen, R.; Tomaczewski, J.; Alavi, A.; Staum, M.; Kundel, H.

    1988-01-01

    To investigate the ability of MRI to detect alterations due to renal ischemia, a rabbit renal artery stenosis (RAS) model was developed. Seven rabbits had RAS induced by surgically encircling the artery with a polyethylene band which had a lumen of 1 mm, 1 to 2 weeks prior to imaging. The stenosis was confirmed by angiography, and the rabbits were then imaged in a 1.4 T research MRI unit. T1 was calculated using four inversion recovery sequences with different inversion times. Renal blood flow, using 113 Sn-microspheres, and regional water content by drying were then measured. The average T1 of the inner medulla was shorter for the ischemia (1574 msec) than for the contralateral kidney (1849 msec), while no change ws noted in the cortex. Ischemic kidneys had less distinct outer medullary zones on IR images with TI = 600 msec than did contralateral or control kidneys. Blood flow to both the cortex and medulla were markedly reduced in ischemic kidneys compared with contralateral kidneys (119.5 vs. 391 ml/min/100 gm for cortex and 19.8 vs. 50.8 ml/min/100 gm for medulla). Renal water and blood content were less affected. Our rabbit model of renal artery stenosis with MRI, radionuclide, and angiographic correlation has the potential to increase our understanding of MR imaging of the rabbit kidney

  16. Radiation dose and diagnostic image quality associated with iterative reconstruction in coronary CT angiography: A systematic review

    International Nuclear Information System (INIS)

    Abdullah, Kamarul Amin; McEntee, Mark F.; Reed, Warren; Kench, Peter L.

    2016-01-01

    The aim of this systematic review is to evaluate the radiation dose reduction achieved using iterative reconstruction (IR) compared to filtered back projection (FBP) in coronary CT angiography (CCTA) and assess the impact on diagnostic image quality. A systematic search of seven electronic databases was performed to identify all studies using a developed keywords strategy. A total of 14 studies met the criteria and were included in a review analysis. The results showed that there was a significant reduction in radiation dose when using IR compared to FBP (P 0.05). The mean ± SD difference of image noise, signal-noise ratio (SNR) and contrast-noise ratio (CNR) were 1.05 ± 1.29 HU, 0.88 ± 0.56 and 0.63 ± 1.83 respectively. The mean ± SD percentages of overall image quality scores were 71.79 ± 12.29% (FBP) and 67.31 ± 22.96% (IR). The mean ± SD percentages of coronary segment analysis were 95.43 ± 2.57% (FBP) and 97.19 ± 2.62% (IR). In conclusion, this review analysis shows that CCTA with the use of IR leads to a significant reduction in radiation dose as compared to the use of FBP. Diagnostic image quality of IR at reduced dose (30–41%) is comparable to FBP at standard dose in the diagnosis of CAD.

  17. Radionuclide angiography and blood pool imaging to assess skin ulcer healing prognosis in patients with peripheral vascular disease

    International Nuclear Information System (INIS)

    Alazraki, N.; Lawrence, P.F.; Syverud, J.B.

    1984-01-01

    Several non-invasive diagnostic techniques including segmental limb blood pressures, skin fluoresence, and photo plethysmography, have been evaluated as predictors of skin ulcer healing in patients with peripheral vascular disease, but none are widely used. Using 20mCi of Tc-99m phosphate compounds, four phase bone scans were obtained, including (1) radionuclide angiogram (2) blood pool image (3) 2 hour and 4-6 hour static images and (4) 24 hour static delayed images. The first two phases were used to assess vacularity to the region of distal extremity ulceration; the last two phases evaluated presence or absence of osteomyelitis. Studies were performed in 30 patients with non-healing ulcers of the lower extremities. Perfusion to the regions of ulceration on images was graded as normal, increased, or reduced with respect to the opposite (presumed normal) limb or some other normal reference area. Hypervascular response was interpreted as good prognosis for healing unless osteomyelitis was present. Clinicians followed patients for 14 days to assess limb healing with optimum care. If there was no improvement, angiography and/or surgery (reconstructive surgery, sympathectomy, or amputation) was done. Results showed: sensitivity for predicting ulcer healing was 94%, specificity 89%. Patients who failed to heal their ulcers showed reduced perfusion, no hypervascular response, or osteomyelitis. Microcirculatory adequacy for ulcer healing appear predictable by this technique

  18. Log-Gabor Energy Based Multimodal Medical Image Fusion in NSCT Domain

    Directory of Open Access Journals (Sweden)

    Yong Yang

    2014-01-01

    Full Text Available Multimodal medical image fusion is a powerful tool in clinical applications such as noninvasive diagnosis, image-guided radiotherapy, and treatment planning. In this paper, a novel nonsubsampled Contourlet transform (NSCT based method for multimodal medical image fusion is presented, which is approximately shift invariant and can effectively suppress the pseudo-Gibbs phenomena. The source medical images are initially transformed by NSCT followed by fusing low- and high-frequency components. The phase congruency that can provide a contrast and brightness-invariant representation is applied to fuse low-frequency coefficients, whereas the Log-Gabor energy that can efficiently determine the frequency coefficients from the clear and detail parts is employed to fuse the high-frequency coefficients. The proposed fusion method has been compared with the discrete wavelet transform (DWT, the fast discrete curvelet transform (FDCT, and the dual tree complex wavelet transform (DTCWT based image fusion methods and other NSCT-based methods. Visually and quantitatively experimental results indicate that the proposed fusion method can obtain more effective and accurate fusion results of multimodal medical images than other algorithms. Further, the applicability of the proposed method has been testified by carrying out a clinical example on a woman affected with recurrent tumor images.

  19. Quality Assurance of Serial 3D Image Registration, Fusion, and Segmentation

    International Nuclear Information System (INIS)

    Sharpe, Michael; Brock, Kristy K.

    2008-01-01

    Radiotherapy relies on images to plan, guide, and assess treatment. Image registration, fusion, and segmentation are integral to these processes; specifically for aiding anatomic delineation, assessing organ motion, and aligning targets with treatment beams in image-guided radiation therapy (IGRT). Future developments in image registration will also improve estimations of the actual dose delivered and quantitative assessment in patient follow-up exams. This article summarizes common and emerging technologies and reviews the role of image registration, fusion, and segmentation in radiotherapy processes. The current quality assurance practices are summarized, and implications for clinical procedures are discussed

  20. Dual-Energy Computed Tomography Angiography of the Lower Extremity Runoff: Impact of Noise-Optimized Virtual Monochromatic Imaging on Image Quality and Diagnostic Accuracy.

    Science.gov (United States)

    Wichmann, Julian L; Gillott, Matthew R; De Cecco, Carlo N; Mangold, Stefanie; Varga-Szemes, Akos; Yamada, Ricardo; Otani, Katharina; Canstein, Christian; Fuller, Stephen R; Vogl, Thomas J; Todoran, Thomas M; Schoepf, U Joseph

    2016-02-01

    The aim of this study was to evaluate the impact of a noise-optimized virtual monochromatic imaging algorithm (VMI+) on image quality and diagnostic accuracy at dual-energy computed tomography angiography (CTA) of the lower extremity runoff. This retrospective Health Insurance Portability and Accountability Act-compliant study was approved by the local institutional review board. We evaluated dual-energy CTA studies of the lower extremity runoff in 48 patients (16 women; mean age, 63.3 ± 13.8 years) performed on a third-generation dual-source CT system. Images were reconstructed with standard linear blending (F_0.5), VMI+, and traditional monochromatic (VMI) algorithms at 40 to 120 keV in 10-keV intervals. Vascular attenuation and image noise in 18 artery segments were measured; signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Five-point scales were used to subjectively evaluate vascular attenuation and image noise. In a subgroup of 21 patients who underwent additional invasive catheter angiography, diagnostic accuracy for the detection of significant stenosis (≥50% lumen restriction) of F_0.5, 50-keV VMI+, and 60-keV VMI data sets were assessed. Objective image quality metrics were highest in the 40- and 50-keV VMI+ series (SNR: 20.2 ± 10.7 and 19.0 ± 9.5, respectively; CNR: 18.5 ± 10.3 and 16.8 ± 9.1, respectively) and were significantly (all P traditional VMI technique and standard linear blending for evaluation of the lower extremity runoff using dual-energy CTA.

  1. Pixel-level multisensor image fusion based on matrix completion and robust principal component analysis

    Science.gov (United States)

    Wang, Zhuozheng; Deller, J. R.; Fleet, Blair D.

    2016-01-01

    Acquired digital images are often corrupted by a lack of camera focus, faulty illumination, or missing data. An algorithm is presented for fusion of multiple corrupted images of a scene using the lifting wavelet transform. The method employs adaptive fusion arithmetic based on matrix completion and self-adaptive regional variance estimation. Characteristics of the wavelet coefficients are used to adaptively select fusion rules. Robust principal component analysis is applied to low-frequency image components, and regional variance estimation is applied to high-frequency components. Experiments reveal that the method is effective for multifocus, visible-light, and infrared image fusion. Compared with traditional algorithms, the new algorithm not only increases the amount of preserved information and clarity but also improves robustness.

  2. Influence of heart rate on diagnostic accuracy and image quality of 16-slice CT coronary angiography: comparison of multisegment and halfscan reconstruction approaches

    International Nuclear Information System (INIS)

    Dewey, Marc; Teige, Florian; Hamm, Bernd; Laule, Michael

    2007-01-01

    The lower the heart rate the better image quality in multislice computed tomography (MSCT) coronary angiography. We prospectively assessed the influence of heart rate on per-patient diagnostic accuracy and image quality of MSCT coronary angiography and compared adaptive multisegment and standard halfscan reconstruction. A consecutive cohort of 126 patients scheduled to undergo conventional coronary angiography was examined with 16-slice CT. For all heart rate groups, per-patient diagnostic accuracy was significantly higher for multisegment than halfscan reconstruction with values of 95 vs. 79% (p 74 bpm, 41 patients). Differences in diagnostic accuracy between adjacent heart rate groups were only significant for halfscan reconstruction for the comparison between the 65-74 and >74 bpm group (p < 0.05). The vessel lengths free of motion artifacts were significantly longer with multisegment reconstruction in all heart rate groups and for all coronary arteries (p < 0.005). For noninvasive MSCT coronary angiography, both per-patient diagnostic accuracy and image quality decline with increasing heart rate, and multisegment reconstruction at high heart rates yields similar results as standard halfscan reconstruction at low heart rates. (orig.)

  3. Influence of heart rate on diagnostic accuracy and image quality of 16-slice CT coronary angiography: comparison of multisegment and halfscan reconstruction approaches

    Energy Technology Data Exchange (ETDEWEB)

    Dewey, Marc; Teige, Florian; Hamm, Bernd [Charite - Universitaetsmedizin Berlin, Humboldt-Universitaet zu Berlin, Department of Radiology, Chariteplatz 1, P.O. Box 10098, Berlin (Germany); Laule, Michael [Department of Cardiology, Charite, Berlin (Germany)

    2007-11-15

    The lower the heart rate the better image quality in multislice computed tomography (MSCT) coronary angiography. We prospectively assessed the influence of heart rate on per-patient diagnostic accuracy and image quality of MSCT coronary angiography and compared adaptive multisegment and standard halfscan reconstruction. A consecutive cohort of 126 patients scheduled to undergo conventional coronary angiography was examined with 16-slice CT. For all heart rate groups, per-patient diagnostic accuracy was significantly higher for multisegment than halfscan reconstruction with values of 95 vs. 79% (p < 0.05, <65 bpm, 38 patients), 85 vs. 66% (p < 0.05, 65-74 bpm, 47 patients), and 78% vs. 41% (p < 0.001, >74 bpm, 41 patients). Differences in diagnostic accuracy between adjacent heart rate groups were only significant for halfscan reconstruction for the comparison between the 65-74 and >74 bpm group (p < 0.05). The vessel lengths free of motion artifacts were significantly longer with multisegment reconstruction in all heart rate groups and for all coronary arteries (p < 0.005). For noninvasive MSCT coronary angiography, both per-patient diagnostic accuracy and image quality decline with increasing heart rate, and multisegment reconstruction at high heart rates yields similar results as standard halfscan reconstruction at low heart rates. (orig.)

  4. Challenges and advantages in wide-field optical coherence tomography angiography imaging of the human retinal and choroidal vasculature at 1.7-MHz A-scan rate

    Science.gov (United States)

    Poddar, Raju; Migacz, Justin V.; Schwartz, Daniel M.; Werner, John S.; Gorczynska, Iwona

    2017-10-01

    We present noninvasive, three-dimensional, depth-resolved imaging of human retinal and choroidal blood circulation with a swept-source optical coherence tomography (OCT) system at 1065-nm center wavelength. Motion contrast OCT imaging was performed with the phase-variance OCT angiography method. A Fourier-domain mode-locked light source was used to enable an imaging rate of 1.7 MHz. We experimentally demonstrate the challenges and advantages of wide-field OCT angiography (OCTA). In the discussion, we consider acquisition time, scanning area, scanning density, and their influence on visualization of selected features of the retinal and choroidal vascular networks. The OCTA imaging was performed with a field of view of 16 deg (5 mm×5 mm) and 30 deg (9 mm×9 mm). Data were presented in en face projections generated from single volumes and in en face projection mosaics generated from up to 4 datasets. OCTA imaging at 1.7 MHz A-scan rate was compared with results obtained from a commercial OCTA instrument and with conventional ophthalmic diagnostic methods: fundus photography, fluorescein, and indocyanine green angiography. Comparison of images obtained from all methods is demonstrated using the same eye of a healthy volunteer. For example, imaging of retinal pathology is presented in three cases of advanced age-related macular degeneration.

  5. Medical images fusion for application in treatment planning systems in radiotherapy

    International Nuclear Information System (INIS)

    Ros, Renato Assenci

    2006-01-01

    Software for medical images fusion was developed for utilization in CAT3D radiotherapy and MNPS radiosurgery treatment planning systems. A mutual information maximization methodology was used to make the image registration of different modalities by measure of the statistical dependence between the voxels pairs. The alignment by references points makes an initial approximation to the non linear optimization process by downhill simplex method for estimation of the joint histogram. The coordinates transformation function use a trilinear interpolation and search for the global maximum value in a 6 dimensional space, with 3 degree of freedom for translation and 3 degree of freedom for rotation, by making use of the rigid body model. This method was evaluated with CT, MR and PET images from Vanderbilt University database to verify its accuracy by comparison of transformation coordinates of each images fusion with gold-standard values. The median of images alignment error values was 1.6 mm for CT-MR fusion and 3.5 mm for PET-MR fusion, with gold-standard accuracy estimated as 0.4 mm for CT-MR fusion and 1.7 mm for PET-MR fusion. The maximum error values were 5.3 mm for CT-MR fusion and 7.4 mm for PET-MR fusion, and 99.1% of alignment errors were images subvoxels values. The mean computing time was 24 s. The software was successfully finished and implemented in 59 radiotherapy routine services, of which 42 are in Brazil and 17 are in Latin America. This method does not have limitation about different resolutions from images, pixels sizes and slice thickness. Besides, the alignment may be accomplished by axial, coronal or sagittal images. (author)

  6. Image quality, radiation dose, and diagnostic accuracy of prospectively ECG-triggered high-pitch coronary CT angiography at 70 kVp in a clinical setting: comparison with invasive coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Long Jiang; Qi, Li; Zhou, Chang Sheng; Zhao, Yan E.; Li, Xie; Lu, Guang Ming [Jinling Hospital, Medical School of Nanjing University, Department of Medical Imaging, Nanjing, Jiangsu (China); Wang, Yining; Cao, Jian; Jin, Zhengyu [Peking Union Medical College Hospital, Department of Radiology, Beijing (China); Schoepf, U.J. [Jinling Hospital, Medical School of Nanjing University, Department of Medical Imaging, Nanjing, Jiangsu (China); Medical University of South Carolina, Division of Cardiovascular Imaging, Charleston, SC (United States); Meinel, Felix G. [Medical University of South Carolina, Division of Cardiovascular Imaging, Charleston, SC (United States); Ludwig-Maximilians-University Hospital, Institute for Clinical Radiology, Munich (Germany); Bayer, Richard R. [Medical University of South Carolina, Division of Cardiovascular Imaging, Charleston, SC (United States); Gong, Jian Bin [Jinling Hospital, Medical School of Nanjing University, Department of Cardiology, Nanjing, Jiangsu (China)

    2016-03-15

    To investigate image quality, radiation dose, and diagnostic performance of prospectively ECG-triggered high-pitch coronary CT angiography (CCTA) at 70 kVp compared to invasive coronary angiography (ICA) as reference standard. Forty-three patients underwent prospectively ECG-triggered high-pitch CCTA at 70 kVp using 30 cc (11 g iodine) contrast medium and ICA. Subjective and objective image quality was evaluated for each CCTA study. CCTA performance for diagnosing ≥50 % stenosis was assessed. Results were stratified according to heart rate (HR), body mass index (BMI), Agatston score, and image quality. At CCTA, 94.3 % (500/530) of coronary segments were of diagnostic quality. Using ICA as reference standard, sensitivity and accuracy were 100 % and 93.0 % on a per-patient basis. Per-vessel and per-segment performances were 92.2 % and 89.5 %; 79.5 % and 88.3 %, respectively. No differences were found in diagnostic accuracy between different HR, BMI, and calcification subgroups (all P > 0.05) on a per-patient basis. However, low image quality reduced diagnostic accuracy on a per-patient, per-vessel and per-segment basis (all P < 0.05). The mean effective radiation dose was 0.2 ± 0.0 mSv. Our presented protocol results in an effective radiation dose of 0.2 mSv and high diagnostic accuracy for stenosis detection in a selected, non-obese population. (orig.)

  7. Improved medical image fusion based on cascaded PCA and shift invariant wavelet transforms.

    Science.gov (United States)

    Reena Benjamin, J; Jayasree, T

    2018-02-01

    In the medical field, radiologists need more informative and high-quality medical images to diagnose diseases. Image fusion plays a vital role in the field of biomedical image analysis. It aims to integrate the complementary information from multimodal images, producing a new composite image which is expected to be more informative for visual perception than any of the individual input images. The main objective of this paper is to improve the information, to preserve the edges and to enhance the quality of the fused image using cascaded principal component analysis (PCA) and shift invariant wavelet transforms. A novel image fusion technique based on cascaded PCA and shift invariant wavelet transforms is proposed in this paper. PCA in spatial domain extracts relevant information from the large dataset based on eigenvalue decomposition, and the wavelet transform operating in the complex domain with shift invariant properties brings out more directional and phase details of the image. The significance of maximum fusion rule applied in dual-tree complex wavelet transform domain enhances the average information and morphological details. The input images of the human brain of two different modalities (MRI and CT) are collected from whole brain atlas data distributed by Harvard University. Both MRI and CT images are fused using cascaded PCA and shift invariant wavelet transform method. The proposed method is evaluated based on three main key factors, namely structure preservation, edge preservation, contrast preservation. The experimental results and comparison with other existing fusion methods show the superior performance of the proposed image fusion framework in terms of visual and quantitative evaluations. In this paper, a complex wavelet-based image fusion has been discussed. The experimental results demonstrate that the proposed method enhances the directional features as well as fine edge details. Also, it reduces the redundant details, artifacts, distortions.

  8. Improved detection probability of low level light and infrared image fusion system

    Science.gov (United States)

    Luo, Yuxiang; Fu, Rongguo; Zhang, Junju; Wang, Wencong; Chang, Benkang

    2018-02-01

    Low level light(LLL) image contains rich information on environment details, but is easily affected by the weather. In the case of smoke, rain, cloud or fog, much target information will lose. Infrared image, which is from the radiation produced by the object itself, can be "active" to obtain the target information in the scene. However, the image contrast and resolution is bad, the ability of the acquisition of target details is very poor, and the imaging mode does not conform to the human visual habit. The fusion of LLL and infrared image can make up for the deficiency of each sensor and give play to the advantages of single sensor. At first, we show the hardware design of fusion circuit. Then, through the recognition probability calculation of the target(one person) and the background image(trees), we find that the trees detection probability of LLL image is higher than that of the infrared image, and the person detection probability of the infrared image is obviously higher than that of LLL image. The detection probability of fusion image for one person and trees is higher than that of single detector. Therefore, image fusion can significantly enlarge recognition probability and improve detection efficiency.

  9. The assessment of multi-sensor image fusion using wavelet transforms for mapping the Brazilian Savanna

    NARCIS (Netherlands)

    Weimar Acerbi, F.; Clevers, J.G.P.W.; Schaepman, M.E.

    2006-01-01

    Multi-sensor image fusion using the wavelet approach provides a conceptual framework for the improvement of the spatial resolution with minimal distortion of the spectral content of the source image. This paper assesses whether images with a large ratio of spatial resolution can be fused, and

  10. MR angiography

    International Nuclear Information System (INIS)

    Masaryk, T.J.; Ross, J.S.

    1991-01-01

    This paper reports on preliminary research and recent clinical experience which indicates that MR angiography can play a role in routine scanning by providing useful information regarding the anatomy of the cerebral circulation. Used in conjunction with conventional spin-echo studies it may improve the overall sensitivity and specificity of MRI in a cost-effective fashion. It does not, however, replace conventional arteriography at this time for either extracranial or intracranial disease. The use of intravascular contrast agents with new fast-scan techniques also provides dynamic information regarding tissue perfusion in a fashion analogous to that of xenon CT. While this work is preliminary, and the exact agents and mathematical models have yet to be defined, the ability to perform parenchymal, angiographic, and physiologic imaging at a single setting is potentially very powerful. Clearly, the role of MR flow techniques deserves further investigation into possible technical refinements, so that accuracy relative to other diagnostic studies and impact upon patient management can be assessed in a meaningful way

  11. Intracranial MR angiography

    International Nuclear Information System (INIS)

    Davis, W.L.; Blatter, D.D.; Parker, D.L.; Robison, R.O.; Harnsberger, H.R.

    1991-01-01

    This paper compares the more traditional three-dimensional (3D) time-of-flight MR angiography with a novel new technique, MOTSA, in the evaluation of both normal and abnormal intracranial anatomy. The authors performed sequential, location-matched 3D TOF and MOTSA MR angiography in 10 subjects with normal and 25 with abnormal intracranial anatomy. Images were evaluated for visualization of specific vessels and depiction of pathologic anatomy. All images were subjected to an objective scoring system. Digital angiography was available in 15 of 25 abnormal cases. In the normal cases, large- and small-vessel visualization was improved. Significant improvement in visualization of venous anatomy was also observed. In the abnormal cases, pathologic anatomy was better visualized, providing important diagnostic information. Multiple overlapping thin-slab-acquisition MR angiography demonstrates vessel visualization that is increased over that of 3D TOF MR angiography in both normal and abnormal cases. Because of the decrease in saturation effects and phase dispersion, MOTSA is especially useful in the evaluation of complex intracranial vascular abnormalities

  12. Physician evaluation and acceptance of remote transmission of CT, digital subtraction angiography, and US annotated images

    International Nuclear Information System (INIS)

    Haskin, M.E.; Robbins, C.; Kohn, M.; Laffey, P.A.; Haskin, P.H.; Teplick, J.G.; Teplick, S.K.; Peyster, R.G.

    1986-01-01

    The authors have found annotated images an effective way of communicating the results of imaging studies to referring physicians. Of particular value is the collation of representative images from several modalities. Previously, hard copy of this collation was sent to the referring physician as an integrated imaging report. Recently they developed a computer-based station that transmits annotated images to remote personal computer (PC) terminals via a telephone modem which requires 30 seconds to send each image. This annotated image report can be quickly accessed by the referring physician at the remote PC terminal The prototype system, utility, diagnostic fidelity, and potential of this remote system are described

  13. CT, MRI and PET image fusion using the ProSoma 3D simulation software

    International Nuclear Information System (INIS)

    Dalah, E.; Bradley, D.A.; Nisbet, A.; Reise, S.

    2008-01-01

    Full text: Multi-modality imaging is involved in almost all oncology applications focusing on the extent of disease and target volume delineation. Commercial image fusion software packages are becoming available but require comprehensive evaluation to ensure reliability of fusion and the underpinning registration algorithm particularly for radiotherapy. The present work seeks to assess such accuracy for a number of available registration methods provided by the commercial package ProSoma. A NEMA body phantom was used in evaluating CT, MR and PET images. In addition, discussion is provided concerning the choice and geometry of fiducial markers in phantom studies and the effect of window-level on target size, in particular in regard to the application of multi modality imaging in treatment planning. In general, the accuracy of fusion of multi-modality images was within 0.5-1.5 mm of actual feature diameters and < 2 ml volume of actual values, particularly in CT images. (author)

  14. 256-Slice coronary computed tomographic angiography in patients with atrial fibrillation: optimal reconstruction phase and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Seitaro; Yuki, Hideaki; Kidoh, Masafumi; Utsunomiya, Daisuke; Nakaura, Takeshi; Namimoto, Tomohiro; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Faculty of Life Sciences, Chuou-ku, Kumamoto (Japan); Honda, Keiichi; Yoshimura, Akira; Katahira, Kazuhiro [Kumamoto Chuo Hospital, Department of Diagnostic Radiology, Minami-ku, Kumamoto (Japan); Noda, Katsuo; Oshima, Shuichi [Kumamoto Chuo Hospital, Department of Cardiology, Minami-ku, Kumamoto (Japan)

    2016-01-15

    To assess the optimal reconstruction phase and the image quality of coronary computed tomographic angiography (CCTA) in patients with atrial fibrillation (AF). We performed CCTA in 60 patients with AF and 60 controls with sinus rhythm. The images were reconstructed in multiple phases in all parts of the cardiac cycle, and the optimal reconstruction phase with the fewest motion artefacts was identified. The coronary artery segments were visually evaluated to investigate their assessability. In 46 (76.7 %) patients, the optimal reconstruction phase was end-diastole, whereas in 6 (10.0 %) patients it was end-systole or mid-diastole, and in 2 (3.3 %) patients it was another cardiac phase. In 53 (88.3 %) of the controls, the optimal reconstruction phase was mid-diastole, whereas it was end-systole in 4 (6.7 %), and in 3 (5.0 %) it was another cardiac phase. There was a significant difference between patients with AF and the controls in the optimal phase (p < 0.01) but not in the visual image quality score (p = 0.06). The optimal reconstruction phase in most patients with AF was the end-diastolic phase. The end-systolic phase tended to be optimal in AF patients with higher average heart rates. (orig.)

  15. Evaluation of 2 different x-ray digital systems designed for cardiovascular angiography: patient dosimetry data and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Octavian Dragusin; Kristien Smans; Hilde Bosmans [Department of Radiology, Gasthuisberg Hospital, Leuven (Belgium); Walter Desmet [Department of Cardiology, Gasthuisberg Hospital, Leuven (Belgium)

    2006-07-01

    The goal of this study was the comparative assessment of dose and image quality performance of a new flat-panel detector (F.D.) and an image intensifier (II) charge coupled device (C.C.D.) installed in a Catheterization laboratory (Cathlab). Poly-methyl methacrylate (PMMA) plates were used to simulate different patient size (10,15,20,25,30 cm). Entrance dose to the phantom and image quality of a test object (Leeds T.O.R. 18-F.G.) were measured. For analysis of image quality, two methods were used. Firstly, images were evaluated directly on the monitor (low contrast resolution and high spatial resolution). Secondly, a numerical method was used (noise and signal-to-noise ratio). Finally a preliminary patient dose survey for the two most common interventional cardiology procedures (coronary angiography C.A. and percutaneous transluminal coronary angioplasty - P.T.C.A.) was performed. Dose area product (D.A.P.), fluoroscopy time (F.T.) and total number of frames (No. frames) were collected. The results showed that both systems performed within international recommendations; the F.D. system seems superior to the II system, in terms of entrance doses of the phantom and image quality. Surprisingly, however, this potential dose reduction is not reflected in the patient data; D.A.P. values of patient data were not significantly reduced with the new system. This underlines the need for a careful set-up of the system and a more detailed analysis of the procedure. (authors)

  16. Evaluation of 2 different x-ray digital systems designed for cardiovascular angiography: patient dosimetry data and image quality

    International Nuclear Information System (INIS)

    Octavian Dragusin; Kristien Smans; Hilde Bosmans; Walter Desmet

    2006-01-01

    The goal of this study was the comparative assessment of dose and image quality performance of a new flat-panel detector (F.D.) and an image intensifier (II) charge coupled device (C.C.D.) installed in a Catheterization laboratory (Cathlab). Poly-methyl methacrylate (PMMA) plates were used to simulate different patient size (10,15,20,25,30 cm). Entrance dose to the phantom and image quality of a test object (Leeds T.O.R. 18-F.G.) were measured. For analysis of image quality, two methods were used. Firstly, images were evaluated directly on the monitor (low contrast resolution and high spatial resolution). Secondly, a numerical method was used (noise and signal-to-noise ratio). Finally a preliminary patient dose survey for the two most common interventional cardiology procedures (coronary angiography C.A. and percutaneous transluminal coronary angioplasty - P.T.C.A.) was performed. Dose area product (D.A.P.), fluoroscopy time (F.T.) and total number of frames (No. frames) were collected. The results showed that both systems performed within international recommendations; the F.D. system seems superior to the II system, in terms of entrance doses of the phantom and image quality. Surprisingly, however, this potential dose reduction is not reflected in the patient data; D.A.P. values of patient data were not significantly reduced with the new system. This underlines the need for a careful set-up of the system and a more detailed analysis of the procedure. (authors)

  17. CT angiography for planning transcatheter aortic valve replacement using automated tube voltage selection: Image quality and radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Mangold, Stefanie [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, Eberhard-Karls University Tuebingen, Tuebingen (Germany); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Kuhlman, Taylor S.; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Duguay, Taylor M. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Tesche, Christian [Department of Cardiology, Heart Centre Munich-Bogenhausen, Munich (Germany); Vogl, Thomas J. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt (Germany); Nikolaou, Konstantin [Department of Diagnostic and Interventional Radiology, Eberhard-Karls University Tuebingen, Tuebingen (Germany); and others

    2017-01-15

    Highlights: • TAVR-planning CT was performed with automated tube voltage selection. • Automated tube voltage selection enables individual tube voltage adaptation. • Image quality was diagnostic while radiation exposure was significantly decreased. - Abstract: Purpose: To assess image quality and accuracy of CT angiography (CTA) for transcatheter aortic valve replacement (TAVR) planning performed with 3rd generation dual-source CT (DSCT). Material and methods: We evaluated 125 patients who underwent TAVR-planning CTA on 3rd generation DSCT. A two-part protocol was performed including retrospectively ECG-gated coronary CTA (CCTA) and prospectively ECG-triggered aortoiliac CTA using 60 mL of contrast medium. Automated tube voltage selection and advanced iterative reconstruction were applied. Effective dose (ED), signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were calculated. Five-point scales were used for subjective image quality analysis. In patients who underwent TAVR, sizing parameters were obtained. Results: Image quality was rated good to excellent in 97.6% of CCTA and 100% of aortoiliac CTAs. CTA studies at >100 kV showed decreased objective image quality compared to 70–100 kV (SNR, all p ≤ 0.0459; CNR, all p ≤ 0.0462). Mean ED increased continuously from 70 to >100 kV (CCTA: 4.5 ± 1.7 mSv–13.6 ± 2.9 mSv, all p ≤ 0.0233; aortoiliac CTA: 2.4 ± 0.9 mSv–6.8 ± 2.7 mSv, all p ≤ 0.0414). In 39 patients TAVR was performed and annulus diameter was within the recommended range in all patients. No severe cardiac or vascular complications were noted. Conclusion: 3rd generation DSCT provides diagnostic image quality in TAVR-planning CTA and facilitates reliable assessment of TAVR device and delivery option while reducing radiation dose.

  18. The evaluation of the radiation dose and image quality through the change of the tube voltage in cerebral CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Won; Jung, Kang Kyo; Cho, Pyong Kon [Radiological Science, Catholic University of Daegu, Daegu (Korea, Republic of)

    2015-06-15

    To image diagnosis in neurovascular diseases using Multi-Detector Computed Tomography (MDCT), injected the same contrast material when inspecting Brain Computed Tomography Angiography (BCTA) to examine radiation dose and Image quality on changing Cerebral Artery CT number by tube voltage. Executed an examination with same condition[Beam Collimation 128 x 0.6 mm, Pitch 0.6, Rotation Time 0.5s, Slice Thickness 5.0 mm, Increment 5.0 mm, Delay Time 3.0 sec, Care Dose 4D (Demension ; D)] except for tube voltage on 50 call patients for BCTA and divided them into two groups (25 people for a group, group A: 80, group B: 120 kVp). From all the acquired images, set a ROI(Region of Interest) on four spots such as left cerebral artery, right cerebral artery, posterior cerebral artery and cerebral parenchyma to compare quantitative evaluation, qualitative evaluation and effective dose after measuring CT number value from Picture Archiving Communications System(PACS). Evaluating images with CT number acquired from BCTA examination, images with 80 kVp was 18 % higher in Signal to Noise Ratio and 19 % in Contrast to Noise Ratio than those with 120 kVp. It was seen that expose dose was decreased by over 50 % with tube voltage 80 kVp than with 120 kVp. Group A (25 patients) was examination with tube voltage 80 kVp while group B with 120 kVp to examine radiation dose and Image quality. It is considered effective to inspect with lower tube voltage than with conventional high kVp, which can reduce radiation dose without any affect on diagnosis.

  19. CT angiography for planning transcatheter aortic valve replacement using automated tube voltage selection: Image quality and radiation exposure

    International Nuclear Information System (INIS)

    Mangold, Stefanie; De Cecco, Carlo N.; Schoepf, U. Joseph; Kuhlman, Taylor S.; Varga-Szemes, Akos; Caruso, Damiano; Duguay, Taylor M.; Tesche, Christian; Vogl, Thomas J.; Nikolaou, Konstantin

    2017-01-01

    Highlights: • TAVR-planning CT was performed with automated tube voltage selection. • Automated tube voltage selection enables individual tube voltage adaptation. • Image quality was diagnostic while radiation exposure was significantly decreased. - Abstract: Purpose: To assess image quality and accuracy of CT angiography (CTA) for transcatheter aortic valve replacement (TAVR) planning performed with 3rd generation dual-source CT (DSCT). Material and methods: We evaluated 125 patients who underwent TAVR-planning CTA on 3rd generation DSCT. A two-part protocol was performed including retrospectively ECG-gated coronary CTA (CCTA) and prospectively ECG-triggered aortoiliac CTA using 60 mL of contrast medium. Automated tube voltage selection and advanced iterative reconstruction were applied. Effective dose (ED), signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were calculated. Five-point scales were used for subjective image quality analysis. In patients who underwent TAVR, sizing parameters were obtained. Results: Image quality was rated good to excellent in 97.6% of CCTA and 100% of aortoiliac CTAs. CTA studies at >100 kV showed decreased objective image quality compared to 70–100 kV (SNR, all p ≤ 0.0459; CNR, all p ≤ 0.0462). Mean ED increased continuously from 70 to >100 kV (CCTA: 4.5 ± 1.7 mSv–13.6 ± 2.9 mSv, all p ≤ 0.0233; aortoiliac CTA: 2.4 ± 0.9 mSv–6.8 ± 2.7 mSv, all p ≤ 0.0414). In 39 patients TAVR was performed and annulus diameter was within the recommended range in all patients. No severe cardiac or vascular complications were noted. Conclusion: 3rd generation DSCT provides diagnostic image quality in TAVR-planning CTA and facilitates reliable assessment of TAVR device and delivery option while reducing radiation dose.

  20. Impact of organ-specific dose reduction on the image quality of head and neck CT angiography

    International Nuclear Information System (INIS)

    Schimmoeller, L.; Lanzman, R.S.; Heusch, P.; Dietrich, S.; Miese, F.; Aissa, J.; Heusner, T.A.; Antoch, G.; Kroepil, P.

    2013-01-01

    Organ-specific dose reduction (OSDR) algorithms can reduce radiation on radiosensitive organs up to 59 %. This study evaluates the influence of a new OSDR algorithm on image quality of head and neck computed tomographic angiography (CTA) in clinical routine. Sixty-two consecutive patients (68 ± 13 years) were randomised into two groups and imaged using 128-row multidetector CT. Group A (n = 31) underwent conventional CTA and group B (n = 31) CTA with a novel OSDR algorithm. Subjective and objective image quality were statistically compared. Subjective image quality was rated on a five-point scale. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated with region-of-interest measurements. The SNR of the common carotid artery and middle cerebral artery was 53.6 ± 22.7 and 43.3 ± 15.3 (group A) versus 54.1 ± 20.5 and 46.2 ± 14.6 (group B). The CNR was 40.0 ± 19.3 and 29.7 ± 12.0 (group A) compared with 40.7 ± 16.8 and 32.9 ± 10.9 (group B), respectively. Subjective image quality was excellent in both groups (mean score 4.4 ± 0.7 versus 4.4 ± 0.6). Differences between the two groups were not significant. The novel OSDR algorithm does not compromise image quality of head and neck CTA. Its application can be recommended for CTA in clinical routine to protect the thyroid gland and ocular lenses from unnecessary high radiation. (orig.)

  1. Image Fusion of CT and MR with Sparse Representation in NSST Domain

    Directory of Open Access Journals (Sweden)

    Chenhui Qiu

    2017-01-01

    Full Text Available Multimodal image fusion techniques can integrate the information from different medical images to get an informative image that is more suitable for joint diagnosis, preoperative planning, intraoperative guidance, and interventional treatment. Fusing images of CT and different MR modalities are studied in this paper. Firstly, the CT and MR images are both transformed to nonsubsampled shearlet transform (NSST domain. So the low-frequency components and high-frequency components are obtained. Then the high-frequency components are merged using the absolute-maximum rule, while the low-frequency components are merged by a sparse representation- (SR- based approach. And the dynamic group sparsity recovery (DGSR algorithm is proposed to improve the performance of the SR-based approach. Finally, the fused image is obtained by performing the inverse NSST on the merged components. The proposed fusion method is tested on a number of clinical CT and MR images and compared with several popular image fusion methods. The experimental results demonstrate that the proposed fusion method can provide better fusion results in terms of subjective quality and objective evaluation.

  2. SAR and Infrared Image Fusion in Complex Contourlet Domain Based on Joint Sparse Representation

    Directory of Open Access Journals (Sweden)

    Wu Yiquan

    2017-08-01

    Full Text Available To investigate the problems of the large grayscale difference between infrared and Synthetic Aperture Radar (SAR images and their fusion image not being fit for human visual perception, we propose a fusion method for SAR and infrared images in the complex contourlet domain based on joint sparse representation. First, we perform complex contourlet decomposition of the infrared and SAR images. Then, we employ the KSingular Value Decomposition (K-SVD method to obtain an over-complete dictionary of the low-frequency components of the two source images. Using a joint sparse representation model, we then generate a joint dictionary. We obtain the sparse representation coefficients of the low-frequency components of the source images in the joint dictionary by the Orthogonal Matching Pursuit (OMP method and select them using the selection maximization strategy. We then reconstruct these components to obtain the fused low-frequency components and fuse the high-frequency components using two criteria——the coefficient of visual sensitivity and the degree of energy matching. Finally, we obtain the fusion image by the inverse complex contourlet transform. Compared with the three classical fusion methods and recently presented fusion methods, e.g., that based on the Non-Subsampled Contourlet Transform (NSCT and another based on sparse representation, the method we propose in this paper can effectively highlight the salient features of the two source images and inherit their information to the greatest extent.

  3. Catheter Angiography

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    Full Text Available ... to your primary care or referring physician , who will discuss the results with you. top of page What are the benefits vs. risks? Benefits Angiography may eliminate the need ...

  4. Catheter Angiography

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    Full Text Available ... diagnosis and treatment in a single procedure. An example is finding an area of severe arterial narrowing, ... contrast material, your radiologist may advise that you take special medication for 24 hours before catheter angiography ...

  5. Catheter Angiography

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    Full Text Available ... possible to combine diagnosis and treatment in a single procedure. Catheter angiography produces very detailed, clear and ... possible to combine diagnosis and treatment in a single procedure. An example is finding an area of ...

  6. Catheter Angiography

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    Full Text Available ... spaghetti. top of page How does the procedure work? Catheter angiography works much the same as a ... angiogram may be performed in less than an hour; however, it may last several hours. top of ...

  7. Catheter Angiography

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    Full Text Available ... accurate pictures of the blood vessels and may eliminate the need for surgery. Tell your doctor if ... are the benefits vs. risks? Benefits Angiography may eliminate the need for surgery. If surgery remains necessary, ...

  8. Catheter Angiography

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    Full Text Available ... spaghetti. top of page How does the procedure work? Catheter angiography works much the same as a ... and x-rays. Manufacturers of intravenous contrast indicate mothers should not breastfeed their babies for 24-48 ...

  9. Catheter Angiography

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    Full Text Available ... of a catheter makes it possible to combine diagnosis and treatment in a single procedure. Catheter angiography ... of a catheter makes it possible to combine diagnosis and treatment in a single procedure. An example ...

  10. Catheter Angiography

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    Full Text Available ... blood flow to the brain and cause a stroke. identify a small aneurysm or arteriovenous malformation (abnormal ... you. top of page What are the benefits vs. risks? Benefits Angiography may eliminate the need for ...

  11. Catheter Angiography

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    Full Text Available ... iodine. If angiography is essential, a variety of methods is used to decrease risk of allergy: You ... radiation oncology provider in your community, you can search the ACR-accredited facilities database . This website does ...

  12. Catheter Angiography

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    Full Text Available ... few millimeters) in the skin where the catheter can be inserted into an artery. The catheter is ... need for surgery. If surgery remains necessary, it can be performed more accurately. Catheter angiography presents a ...

  13. Catheter Angiography

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    Full Text Available ... examine blood vessels in key areas of the body for abnormalities such as aneurysms and disease such ... to produce pictures of blood vessels in the body. Angiography is performed using: x-rays with catheters ...

  14. Catheter Angiography

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    Full Text Available ... 20 minutes (or by using a special closure device). When the examination is complete, you may be ... contrast material, your radiologist may advise that you take special medication for 24 hours before catheter angiography ...

  15. Catheter Angiography

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    Full Text Available ... rays ). top of page What are some common uses of the procedure? Catheter angiography is used to ... community, you can search the ACR-accredited facilities database . This website does not provide cost information. The ...

  16. Catheter Angiography

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    Full Text Available ... spaghetti. top of page How does the procedure work? Catheter angiography works much the same as a ... possible to combine diagnosis and treatment in a single procedure. An example is finding an area of ...

  17. Catheter Angiography

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    Full Text Available ... with you. top of page What are the benefits vs. risks? Benefits Angiography may eliminate the need for surgery. If ... cancer from excessive exposure to radiation. However, the benefit of an accurate diagnosis far outweighs the risk. ...

  18. Catheter Angiography

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    Full Text Available ... top of page What are the benefits vs. risks? Benefits Angiography may eliminate the need for surgery. ... in the typical diagnostic range for this exam. Risks There is always a slight chance of cancer ...

  19. Catheter Angiography

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    Full Text Available ... most cases, the kidneys will regain their normal function within five to seven days. Rarely, the catheter ... limitations of Catheter Angiography? Patients with impaired kidney function, especially those who also have diabetes, are not ...

  20. Catheter Angiography

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    Full Text Available ... serious allergic reaction to contrast materials that contain iodine is extremely rare, and radiology departments are well- ... having a reaction to contrast materials that contain iodine. If angiography is essential, a variety of methods ...

  1. An object-oriented framework for medical image registration, fusion, and visualization.

    Science.gov (United States)

    Zhu, Yang-Ming; Cochoff, Steven M

    2006-06-01

    An object-oriented framework for image registration, fusion, and visualization was developed based on the classic model-view-controller paradigm. The framework employs many design patterns to facilitate legacy code reuse, manage software complexity, and enhance the maintainability and portability of the framework. Three sample applications built a-top of this framework are illustrated to show the effectiveness of this framework: the first one is for volume image grouping and re-sampling, the second one is for 2D registration and fusion, and the last one is for visualization of single images as well as registered volume images.

  2. Multi-Scale Pixel-Based Image Fusion Using Multivariate Empirical Mode Decomposition

    Directory of Open Access Journals (Sweden)

    Naveed ur Rehman

    2015-05-01

    Full Text Available A novel scheme to perform the fusion of multiple images using the multivariate empirical mode decomposition (MEMD algorithm is proposed. Standard multi-scale fusion techniques make a priori assumptions regarding input data, whereas standard univariate empirical mode decomposition (EMD-based fusion techniques suffer from inherent mode mixing and mode misalignment issues, characterized respectively by either a single intrinsic mode function (IMF containing multiple scales or the same indexed IMFs corresponding to multiple input images carrying different frequency information. We show that MEMD overcomes these problems by being fully data adaptive and by aligning common frequency scales from multiple channels, thus enabling their comparison at a pixel level and subsequent fusion at multiple data scales. We then demonstrate the potential of the proposed scheme on a large dataset of real-world multi-exposure and multi-focus images and compare the results against those obtained from standard fusion algorithms, including the principal component analysis (PCA, discrete wavelet transform (DWT and non-subsampled contourlet transform (NCT. A variety of image fusion quality measures are employed for the objective evaluation of the proposed method. We also report the results of a hypothesis testing approach on our large image dataset to identify statistically-significant performance differences.

  3. Multi-focus image fusion with the all convolutional neural network

    Science.gov (United States)

    Du, Chao-ben; Gao, She-sheng

    2018-01-01

    A decision map contains complete and clear information about the image to be fused, which is crucial to various image fusion issues, especially multi-focus image fusion. However, in order to get a satisfactory image fusion effect, getting a decision map is very necessary and usually difficult to finish. In this letter, we address this problem with convolutional neural network (CNN), aiming to get a state-of-the-art decision map. The main idea is that the max-pooling of CNN is replaced by a convolution layer, the residuals are propagated backwards by gradient descent, and the training parameters of the individual layers of the CNN are updated layer by layer. Based on this, we propose a new all CNN (ACNN)-based multi-focus image fusion method in spatial domain. We demonstrate that the decision map obtained from the ACNN is reliable and can lead to high-quality fusion results. Experimental results clearly validate that the proposed algorithm can obtain state-of-the-art fusion performance in terms of both qualitative and quantitative evaluations.

  4. MR angiography (MRA)

    Energy Technology Data Exchange (ETDEWEB)

    Hasuo, Kanehiro [Kyushu Univ., Fukuoka (Japan). Faculty of Medicine

    1995-12-01

    The primary goal of vascular imaging is the visualization of morphology and hemodynamics. Catheter angiography has been regarded as a gold standard for this purpose. However, MR angiography (MRA) is now increasingly being recognized as an important noninvasive technique for the depiction of vascular diseases and is partially superseding catheter angiography. The author evaluated the usefulness of MRA in the diagnosis of cerebral aneurysms and moyamoya disease. All aneurysms 5 mm or larger in diameter could be detected and most of those less than 5 mm in diameter were also detectable with using a combination of MIP images, target MIP images and source images. In moyamoya disease, the diagnosis could be made in all. For hemodynamic changes, flow directions in the circle of Willis could be visualized by phase-contrast MRA in a normal volunteer. In addition, MRA successfully showed the patency of surgical collaterals in cases of moyamoya disease. Despite some limitations compared with catheter angiography, MRA has a high sensitivity and specificity in the diagnosis of cerebrovascular abnormalities. Furthermore, screening of cerebral aneurysms or cerebrovascular occlusive diseases seems to be a new, and important indication for MRA. (author).

  5. Optimization of hybrid iterative reconstruction level and evaluation of image quality and radiation dose for pediatric cardiac computed tomography angiography

    International Nuclear Information System (INIS)

    Yang, Lin; Liang, Changhong; Zhuang, Jian; Huang, Meiping; Liu, Hui

    2017-01-01

    Hybrid iterative reconstruction can reduce image noise and produce better image quality compared with filtered back-projection (FBP), but few reports describe optimization of the iteration level. We optimized the iteration level of iDose"4 and evaluated image quality for pediatric cardiac CT angiography. Children (n = 160) with congenital heart disease were enrolled and divided into full-dose (n = 84) and half-dose (n = 76) groups. Four series were reconstructed using FBP, and iDose"4 levels 2, 4 and 6; we evaluated subjective quality of the series using a 5-grade scale and compared the series using a Kruskal-Wallis H test. For FBP and iDose"4-optimal images, we compared contrast-to-noise ratios (CNR) and size-specific dose estimates (SSDE) using a Student's t-test. We also compared diagnostic-accuracy of each group using a Kruskal-Wallis H test. Mean scores for iDose"4 level 4 were the best in both dose groups (all P < 0.05). CNR was improved in both groups with iDose"4 level 4 as compared with FBP. Mean decrease in SSDE was 53% in the half-dose group. Diagnostic accuracy for the four datasets were in the range 92.6-96.2% (no statistical difference). iDose"4 level 4 was optimal for both the full- and half-dose groups. Protocols with iDose"4 level 4 allowed 53% reduction in SSDE without significantly affecting image quality and diagnostic accuracy. (orig.)

  6. TH-CD-206-12: Image-Based Motion Estimation for Plaque Visualization in Coronary Computed Tomography Angiography

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X; Sisniega, A; Zbijewski, W; Stayman, J [Johns Hopkins University, Balitmore, MD (United States); Contijoch, F; McVeigh, E [University of California, San Diego, San Diego, CA (United States)

    2016-06-15

    Purpose: Visualization and quantification of coronary artery calcification and atherosclerotic plaque benefits from coronary artery motion (CAM) artifact elimination. This work applies a rigid linear motion model to a Volume of Interest (VoI) for estimating motion estimation and compensation of image degradation in Coronary Computed Tomography Angiography (CCTA). Methods: In both simulation and testbench experiments, translational CAM was generated by displacement of the imaging object (i.e. simulated coronary artery and explanted human heart) by ∼8 mm, approximating the motion of a main coronary branch. Rotation was assumed to be negligible. A motion degraded region containing a calcification was selected as the VoI. Local residual motion was assumed to be rigid and linear over the acquisition window, simulating motion observed during diastasis. The (negative) magnitude of the image gradient of the reconstructed VoI was chosen as the motion estimation objective and was minimized with Covariance Matrix Adaptation Evolution Strategy (CMAES). Results: Reconstruction incorporated the estimated CAM yielded signification recovery of fine calcification structures as well as reduced motion artifacts within the selected local region. The compensated reconstruction was further evaluated using two image similarity metrics, the structural similarity index (SSIM) and Root Mean Square Error (RMSE). At the calcification site, the compensated data achieved a 3% increase in SSIM and a 91.2% decrease in RMSE in comparison with the uncompensated reconstruction. Conclusion: Results demonstrate the feasibility of our image-based motion estimation method exploiting a local rigid linear model for CAM compensation. The method shows promising preliminary results for the application of such estimation in CCTA. Further work will involve motion estimation of complex motion corrupted patient data acquired from clinical CT scanner.

  7. In vivo optical imaging of amblyopia: Digital subtraction autofluorescence and split-spectrum amplitude-decorrelation angiography.

    Science.gov (United States)

    Guo, Lei; Tao, Jun; Xia, Fan; Yang, Zhi; Ma, Xiaoli; Hua, Rui

    2016-09-01

    Amblyopia is a visual impairment that is attributed to either abnormal binocular interactions or visual deprivation. The retina and choroids have been shown to be involved in the development of amblyopia. The purpose of this study was to investigate the retinal and choroidal microstructural abnormalities of amblyopia using digital subtraction autofluorescence and split-spectrum amplitude-decorrelation angiography (SSADA) approaches. This prospective study included 44 eyes of 22 patients with unilateral amblyopia. All patients who received indirect ophthalmoscopy, combined depth imaging spectral domain optical coherence tomography (OCT), SSADA-OCT, and macular blue light (BL-) and near-infrared (NIR-) autofluorescences underwent pupil dilation. The subfoveal choroidal thickness (SFCT) was measured. BL- and NIR-autofluorescences were determined for all patients and used to generate subtraction images with ImageJ software. The superficial, deep layers of the retina, and inner choroid layer were required for SSADA-OCT. For the normal eyes, a regularly increasing signal was observed in the central macula based on the subtraction images. In contrast, a decreased signal for the central patch or a reduced peak was detected in 16 of 22 amblyopic eyes (72.7%). The mean SFCT of the amblyopic eyes was greater than that of the fellow normal eyes (399.25 ± 4.944 µm vs. 280.58 ± 6.491 µm, respectively, P autofluorescence. The mechanistic relationship of a thicker choroid and choroidal capillary atrophy with amblyopia remains to be described. The digital subtraction image confirmed the changes in the microstructure of the amblyopic retina as a supplementary approach to detect the progression of amblyopia. Lasers Surg. Med. 48:660-667, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  8. Optimization of hybrid iterative reconstruction level and evaluation of image quality and radiation dose for pediatric cardiac computed tomography angiography

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lin; Liang, Changhong [Southern Medical University, Guangzhou (China); Guangdong Academy of Medical Sciences, Dept. of Radiology, Guangdong General Hospital, Guangzhou (China); Zhuang, Jian [Guangdong Academy of Medical Sciences, Dept. of Cardiac Surgery, Guangdong Cardiovascular Inst., Guangdong Provincial Key Lab. of South China Structural Heart Disease, Guangdong General Hospital, Guangzhou (China); Huang, Meiping [Guangdong Academy of Medical Sciences, Dept. of Radiology, Guangdong General Hospital, Guangzhou (China); Guangdong Academy of Medical Sciences, Dept. of Catheterization Lab, Guangdong Cardiovascular Inst., Guangdong Provincial Key Lab. of South China Structural Heart Disease, Guangdong General Hospital, Guangzhou (China); Liu, Hui [Guangdong Academy of Medical Sciences, Dept. of Radiology, Guangdong General Hospital, Guangzhou (China)

    2017-01-15

    Hybrid iterative reconstruction can reduce image noise and produce better image quality compared with filtered back-projection (FBP), but few reports describe optimization of the iteration level. We optimized the iteration level of iDose{sup 4} and evaluated image quality for pediatric cardiac CT angiography. Children (n = 160) with congenital heart disease were enrolled and divided into full-dose (n = 84) and half-dose (n = 76) groups. Four series were reconstructed using FBP, and iDose{sup 4} levels 2, 4 and 6; we evaluated subjective quality of the series using a 5-grade scale and compared the series using a Kruskal-Wallis H test. For FBP and iDose{sup 4}-optimal images, we compared contrast-to-noise ratios (CNR) and size-specific dose estimates (SSDE) using a Student's t-test. We also compared diagnostic-accuracy of each group using a Kruskal-Wallis H test. Mean scores for iDose{sup 4} level 4 were the best in both dose groups (all P < 0.05). CNR was improved in both groups with iDose{sup 4} level 4 as compared with FBP. Mean decrease in SSDE was 53% in the half-dose group. Diagnostic accuracy for the four datasets were in the range 92.6-96.2% (no statistical difference). iDose{sup 4} level 4 was optimal for both the full- and half-dose groups. Protocols with iDose{sup 4} level 4 allowed 53% reduction in SSDE without significantly affecting image quality and diagnostic accuracy. (orig.)

  9. Dual Channel Pulse Coupled Neural Network Algorithm for Fusion of Multimodality Brain Images with Quality Analysis

    Directory of Open Access Journals (Sweden)

    Kavitha SRINIVASAN

    2014-09-01

    Full Text Available Background: In the review of medical imaging techniques, an important fact that emerged is that radiologists and physicians still are in a need of high-resolution medical images with complementary information from different modalities to ensure efficient analysis. This requirement should have been sorted out using fusion techniques with the fused image being used in image-guided surgery, image-guided radiotherapy and non-invasive diagnosis. Aim: This paper focuses on Dual Channel Pulse Coupled Neural Network (PCNN Algorithm for fusion of multimodality brain images and the fused image is further analyzed using subjective (human perception and objective (statistical measures for the quality analysis. Material and Methods: The modalities used in fusion are CT, MRI with subtypes T1/T2/PD/GAD, PET and SPECT, since the information from each modality is complementary to one another. The objective measures selected for evaluation of fused image were: Information Entropy (IE - image quality, Mutual Information (MI – deviation in fused to the source images and Signal to Noise Ratio (SNR – noise level, for analysis. Eight sets of brain images with different modalities (T2 with T1, T2 with CT, PD with T2, PD with GAD, T2 with GAD, T2 with SPECT-Tc, T2 with SPECT-Ti, T2 with PET are chosen for experimental purpose and the proposed technique is compared with existing fusion methods such as the Average method, the Contrast pyramid, the Shift Invariant Discrete Wavelet Transform (SIDWT with Harr and the Morphological pyramid, using the selected measures to ascertain relative performance. Results: The IE value and SNR value of the fused image derived from dual channel PCNN is higher than other fusion methods, shows that the quality is better with less noise. Conclusion: The fused image resulting from the proposed method retains the contrast, shape and texture as in source images without false information or information loss.

  10. Data Fusion and Fuzzy Clustering on Ratio Images for Change Detection in Synthetic Aperture Radar Images

    Directory of Open Access Journals (Sweden)

    Wenping Ma

    2014-01-01

    Full Text Available The unsupervised approach to change detection via synthetic aperture radar (SAR images becomes more and more popular. The three-step procedure is the most widely used procedure, but it does not work well with the Yellow River Estuary dataset obtained by two synthetic aperture radars. The difference of the two radars in imaging techniques causes severe noise, which seriously affects the difference images generated by a single change detector in step two, producing the difference image. To deal with problem, we propose a change detector to fuse the log-ratio (LR and the mean-ratio (MR images by a context independent variable behavior (CIVB operator and can utilize the complement information in two ratio images. In order to validate the effectiveness of the proposed change detector, the change detector will be compared with three other change detectors, namely, the log-ratio (LR, mean-ratio (MR, and the wavelet-fusion (WR operator, to deal with three datasets with different characteristics. The four operators are applied not only in a widely used three-step procedure but also in a new approach. The experiments show that the false alarms and overall errors of change detection are greatly reduced, and the kappa and KCC are improved a lot. And its superiority can also be observed visually.

  11. Analyzer-based imaging of spinal fusion in an animal model

    International Nuclear Information System (INIS)

    Kelly, M E; Beavis, R C; Allen, L A; Fiorella, David; Schueltke, E; Juurlink, B H; Chapman, L D; Zhong, Z

    2008-01-01

    Analyzer-based imaging (ABI) utilizes synchrotron radiation sources to create collimated monochromatic x-rays. In addition to x-ray absorption, this technique uses refraction and scatter rejection to create images. ABI provides dramatically improved contrast over standard imaging techniques. Twenty-one adult male Wistar rats were divided into four experimental groups to undergo the following interventions: (1) non-injured control, (2) decortication alone, (3) decortication with iliac crest bone grafting and (4) decortication with iliac crest bone grafting and interspinous wiring. Surgical procedures were performed at the L5-6 level. Animals were killed at 2, 4 and 6 weeks after the intervention and the spine muscle blocks were excised. Specimens were assessed for the presence of fusion by (1) manual testing, (2) conventional absorption radiography and (3) ABI. ABI showed no evidence of bone fusion in groups 1 and 2 and showed solid or possibly solid fusion in subjects from groups 3 and 4 at 6 weeks. Metal artifacts were not present in any of the ABI images. Conventional absorption radiographs did not provide diagnostic quality imaging of either the graft material or fusion masses in any of the specimens in any of the groups. Synchrotron-based ABI represents a novel imaging technique which can be used to assess spinal fusion in a small animal model. ABI produces superior image quality when compared to conventional radiographs

  12. Analyzer-based imaging of spinal fusion in an animal model

    Science.gov (United States)

    Kelly, M. E.; Beavis, R. C.; Fiorella, David; Schültke, E.; Allen, L. A.; Juurlink, B. H.; Zhong, Z.; Chapman, L. D.

    2008-05-01

    Analyzer-based imaging (ABI) utilizes synchrotron radiation sources to create collimated monochromatic x-rays. In addition to x-ray absorption, this technique uses refraction and scatter rejection to create images. ABI provides dramatically improved contrast over standard imaging techniques. Twenty-one adult male Wistar rats were divided into four experimental groups to undergo the following interventions: (1) non-injured control, (2) decortication alone, (3) decortication with iliac crest bone grafting and (4) decortication with iliac crest bone grafting and interspinous wiring. Surgical procedures were performed at the L5-6 level. Animals were killed at 2, 4 and 6 weeks after the intervention and the spine muscle blocks were excised. Specimens were assessed for the presence of fusion by (1) manual testing, (2) conventional absorption radiography and (3) ABI. ABI showed no evidence of bone fusion in groups 1 and 2 and showed solid or possibly solid fusion in subjects from groups 3 and 4 at 6 weeks. Metal artifacts were not present in any of the ABI images. Conventional absorption radiographs did not provide diagnostic quality imaging of either the graft material or fusion masses in any of the specimens in any of the groups. Synchrotron-based ABI represents a novel imaging technique which can be used to assess spinal fusion in a small animal model. ABI produces superior image quality when compared to conventional radiographs.

  13. Development of a two-dimensional imaging system for clinical applications of intravenous coronary angiography using intense synchrotron radiation produced by a multipole wiggler

    International Nuclear Information System (INIS)

    Hyodo, K.; Ando, M.; Oku, Y.; Yamamoto, S.; Takeda, T.; Itai, Y.; Ohtsuka, S.; Sugishita, Y.; Tada, J.

    1998-01-01

    A two-dimensional clinical intravenous coronary angiography system, comprising a large-size View area produced by asymmetrical reflection from a silicon crystal using intense synchrotron radiation from a multipole wiggler and a two-dimensional detector with an image intensifier, has been completed. An advantage of the imaging system is that two-dimensional dynamic imaging of the cardiovascular system can be achieved due to its two-dimensional radiation field. This world-first two-dimensional system has been successfully adapted to clinical applications. Details of the imaging system are described in this paper

  14. Development of a two-dimensional imaging system for clinical applications of intravenous coronary angiography using intense synchrotron radiation produced by a multipole wiggler

    Energy Technology Data Exchange (ETDEWEB)

    Hyodo, K.; Ando, M. [High Energy Accelerator Research Organization, Inst. of Material Structure Sciences, Tsukuba (Japan); Oku, Y.; Yamamoto, S. [Graduated School for Advanced Sciences, Tsukuba (Japan); Takeda, T.; Itai, Y.; Ohtsuka, S.; Sugishita, Y. [The Univ. of Tsukuba, Inst. of Clinical Medicine, Tsukuba (Japan); Tada, J. [The Univ. of Tsukuba, Inst. of Basic Medical Sciences, Tsukuba (Japan)

    1998-05-01

    A two-dimensional clinical intravenous coronary angiography system, comprising a large-size View area produced by asymmetrical reflection from a silicon crystal using intense synchrotron radiation from a multipole wiggler and a two-dimensional detector with an image intensifier, has been completed. An advantage of the imaging system is that two-dimensional dynamic imaging of the cardiovascular system can be achieved due to its two-dimensional radiation field. This world-first two-dimensional system has been successfully adapted to clinical applications. Details of the imaging system are described in this paper. 18 refs.

  15. A Remote Sensing Image Fusion Method based on adaptive dictionary learning

    Science.gov (United States)

    He, Tongdi; Che, Zongxi

    2018-01-01

    This paper discusses using a remote sensing fusion method, based on' adaptive sparse representation (ASP)', to provide improved spectral information, reduce data redundancy and decrease system complexity. First, the training sample set is formed by taking random blocks from the images to be fused, the dictionary is then constructed using the training samples, and the remaining terms are clustered to obtain the complete dictionary by iterated processing at each step. Second, the self-adaptive weighted coefficient rule of regional energy is used to select the feature fusion coefficients and complete the reconstruction of the image blocks. Finally, the reconstructed image blocks are rearranged and an average is taken to obtain the final fused images. Experimental results show that the proposed method is superior to other traditional remote sensing image fusion methods in both spectral information preservation and spatial resolution.

  16. Multidetector-CT angiography in pulmonary embolism - can image parameters predict clinical outcome?

    Energy Technology Data Exchange (ETDEWEB)

    Heyer, Christoph M.; Lemburg, Stefan P.; Nicolas, Volkmar; Roggenland, Daniela [Berufsgenossenschaftliches Universitaetsklinikum Bergmannsheil GmbH, Ruhr-University of Bochum, Institute of Diagnostic Radiology, Interventional Radiology and Nuclear Medicine, Bochum (Germany); Knoop, Heiko [Berufsgenossenschaftliches Universitaetsklinikum Bergmannsheil GmbH, Medical Clinic III - Pneumology, Allergology, and Sleep Medicine, Bochum (Germany); Holland-Letz, Tim [Ruhr-University of Bochum, Department of Medical Informatics, Biometry and Epidemiology, Bochum (Germany)

    2011-09-15

    To assess if pulmonary CT angiography (CTA) can predict outcome in patients with pulmonary embolism (PE). Retrospective analysis of CTA studies of patients with PE and documentation of pulmonary artery (PA)/aorta ratio, right ventricular (RV)/left ventricular (LV) ratio, superior vena cava (SVC) diameter, pulmonary obstruction index (POI), ventricular septal bowing (VSB), venous contrast reflux (VCR), pulmonary infarction and pleural effusion. Furthermore, duration of total hospital stay, necessity for/duration of ICU therapy, necessity for mechanical ventilation and mortality were recorded. Comparison was performed by logistic/linear regression analysis with significance at 5%. 152 patients were investigated. Mean duration of hospital stay was 21 {+-} 24 days. 66 patients were admitted to the ICU; 20 received mechanical ventilation. Mean duration of ICU therapy was 3 {+-} 8 days. Mortality rate was 8%. Significant positive associations of POI, VCR and pulmonary infarction with necessity for ICU therapy were shown. VCR was significantly associated with necessity for mechanical ventilation and duration of ICU treatment. Pleural effusions were significantly associated with duration of total hospital stay whereas the RV/LV ratio correlated with mortality. Selected CTA findings showed significant associations with the clinical course of PE and may thus be used as predictive parameters. (orig.)

  17. Exploiting magnetic resonance angiography imaging improves model estimation of BOLD signal.

    Directory of Open Access Journals (Sweden)

    Zhenghui Hu

    Full Text Available The change of BOLD signal relies heavily upon the resting blood volume fraction ([Formula: see text] associated with regional vasculature. However, existing hemodynamic data assimilation studies pretermit such concern. They simply assign the value in a physiologically plausible range to get over ill-conditioning of the assimilation problem and fail to explore actual [Formula: see text]. Such performance might lead to unreliable model estimation. In this work, we present the first exploration of the influence of [Formula: see text] on fMRI data assimilation, where actual [Formula: see text] within a given cortical area was calibrated by an MR angiography experiment and then was augmented into the assimilation scheme. We have investigated the impact of [Formula: see text] on single-region data assimilation and multi-region data assimilation (dynamic cause modeling, DCM in a classical flashing checkerboard experiment. Results show that the employment of an assumed [Formula: see text] in fMRI data assimilation is only suitable for fMRI signal reconstruction and activation detection grounded on this signal, and not suitable for estimation of unobserved states and effective connectivity study. We thereby argue that introducing physically realistic [Formula: see text] in the assimilation process may provide more reliable estimation of physiological information, which contributes to a better understanding of the underlying hemodynamic processes. Such an effort is valuable and should be well appreciated.

  18. Two-dimensional real-time imaging system for subtraction angiography using an iodine filter

    Science.gov (United States)

    Umetani, Keiji; Ueda, Ken; Takeda, Tohoru; Anno, Izumi; Itai, Yuji; Akisada, Masayoshi; Nakajima, Teiichi

    1992-01-01

    A new type of subtraction imaging system was developed using an iodine filter and a single-energy broad bandwidth monochromatized x ray. The x-ray images of coronary arteries made after intravenous injection of a contrast agent are enhanced by an energy-subtraction technique. Filter chopping of the x-ray beam switches energies rapidly, so that a nearly simultaneous pair of filtered and nonfiltered images can be made. By using a high-speed video camera, a pair of two 512 × 512 pixel images can be obtained within 9 ms. Three hundred eighty-four images (raw data) are stored in a 144-Mbyte frame memory. After phantom studies, in vivo subtracted images of coronary arteries in dogs were obtained at a rate of 15 images/s.

  19. Towards risk stratification in systemic atherosclerosis: value of myocardial function and viability imaging as an adjunct to MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Seeger, Achim; Fenchel, Michael; Kramer, Ulrich; Bretschneider, Christiane; Grimm, Florian; Klumpp, Bernhard; Claussen, Claus D.; Miller, Stephan [Eberhard Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Scheule, Albertus [Eberhard Karls University Tuebingen, Department for Thorax, Cardiac and Vascular Surgery, Tuebingen (Germany); Balletshofer, Bernd [Eberhard Karls University Tuebingen, Department of Internal Medicine IV, Tuebingen (Germany)

    2010-04-15

    To longitudinally assess the value of cardiac functional and viability imaging as a supplement to MR angiography in patients with atherosclerotic disease. Cardiac MRI was performed in 195 consecutive patients with symptomatic peripheral arterial disease. Of these, 186 patients were followed for 22 {+-} 5 months for the presence of cardiac events (cardiac death, acute coronary syndrome and hospitalisation as a result of congestive heart failure). Myocardial viability imaging showed a high prevalence of known (n = 31) and occult myocardial infarctions (MI) (n = 26). Cardiac events occurred more often in patients with reduced ventricular function (ejection fraction (EF) less than 40%, cardiac event in 4/8 patients; EF 40-55%, cardiac event in 10/40 patients; EF greater than 55%, cardiac event in 15/138 patients) as well as in patients with occult MI (8/25 patients) and known MI (11/30 patients). In patients with normal function, the detection of a previous MI was of high relevance to prognosis. Both reduced EF and the presence of MI influence patients' prognoses. Performing cardiac MRI in this patient population may influence further patient management including intensified risk factor intervention. (orig.)

  20. Towards risk stratification in systemic atherosclerosis: value of myocardial function and viability imaging as an adjunct to MR angiography

    International Nuclear Information System (INIS)

    Seeger, Achim; Fenchel, Michael; Kramer, Ulrich; Bretschneider, Christiane; Grimm, Florian; Klumpp, Bernhard; Claussen, Claus D.; Miller, Stephan; Scheule, Albertus; Balletshofer, Bernd

    2010-01-01

    To longitudinally assess the value of cardiac functional and viability imaging as a supplement to MR angiography in patients with atherosclerotic disease. Cardiac MRI was performed in 195 consecutive patients with symptomatic peripheral arterial disease. Of these, 186 patients were followed for 22 ± 5 months for the presence of cardiac events (cardiac death, acute coronary syndrome and hospitalisation as a result of congestive heart failure). Myocardial viability imaging showed a high prevalence of known (n = 31) and occult myocardial infarctions (MI) (n = 26). Cardiac events occurred more often in patients with reduced ventricular function (ejection fraction (EF) less than 40%, cardiac event in 4/8 patients; EF 40-55%, cardiac event in 10/40 patients; EF greater than 55%, cardiac event in 15/138 patients) as well as in patients with occult MI (8/25 patients) and known MI (11/30 patients). In patients with normal function, the detection of a previous MI was of high relevance to prognosis. Both reduced EF and the presence of MI influence patients' prognoses. Performing cardiac MRI in this patient population may influence further patient management including intensified risk factor intervention. (orig.)

  1. Impaired left ventricular function has a detrimental effect on image quality in multi-detector row CT coronary angiography

    International Nuclear Information System (INIS)

    Manghat, N.E.; Morgan-Hughes, G.J.; Shaw, S.R.; Marshall, A.J.; Roobottom, C.A.

    2008-01-01

    Aim: To determine whether there is a relationship between left ventricular (LV) haemodynamic parameters, circulation times, and arterial contrast opacification that might affect the image quality of computed tomography (CT) coronary angiography. Methods: Thirty-six patients were included in the study: 18 with cardiomyopathy (CM) and LV dilatation of suspected ischaemic aetiology [age 57.9 ± 13.7 years, range 30-77 years; 14 male, four female; body mass index (BMI) = 27.7 ± 4.5, range 25.5-31.8] and 18 controls (age 62.3 ± 9.4 years, range 47-89 years; 10 male, eight female; BMI 27.8 ± 6.6; range 19.2-33.6). Coronary artery image quality was assessed using a three-point visual scale; contrast medium circulation times, aortic root contrast attenuation, and LV functional parameters were studied. Results: Visually reduced contrast opacification impaired image quality more often in the CM group than the control group (27.4 versus 5.1%). A total of 55.6% CM patients had a contrast transit time ranging from 30-75 s; the number of 'unassessable' segments increased with increasing transit time conforming to a fitted quadratic model (R 2 = 0.74). The relationship between LV ejection fraction and contrast attenuation may also conform to a quadratic model (R 2 = 0.71). Conclusion: LV haemodynamics influence coronary artery opacification using cardiac CT, and users imaging this subgroup must do so with the knowledge of this potential pitfall. The results indicate the need for further studies examining CT protocols in this clinical subgroup

  2. Imaging of the Coronary Venous System: Validation of Three-Dimensional Rotational Venous Angiography Against Dual-Source Computed Tomography

    International Nuclear Information System (INIS)

    Knackstedt, Christian; Muehlenbruch, Georg; Mischke, Karl; Bruners, Philipp; Schimpf, Thomas; Frechen, Dirk; Schummers, Georg; Mahnken, Andreas H.; Guenther, Rolf W.; Kelm, Malte; Schauerte, Patrick

    2008-01-01

    Information on the anatomy of the cardiac venous system (CVS) is increasingly important for cardiac resynchronization therapy or percutaneous transvenous mitral valve annuloplasty. Three-dimensional (3D) imaging can further improve the understanding of the relationship of cardiac structures. This study was performed to validate the accuracy of rotational coronary sinus angiography (CSA) displaying the 3D anatomy of the CVS compared to ECG-gated, contrast-enhanced, cardiac dual-source computed tomography (DSCT). Five domestic pigs (60 kg) underwent DSCT using a standardized examination protocol. Using a standard C-arm for fluoroscopy, a rotational CSA was obtained and 3D-image reconstructions performed. Side branches were identified using both methods and enumerated. Vessel visibility was estimated for each side branch and great cardiac vein/anterior interventricular vein. Also, vessel diameters were measured at distinct landmarks, i.e., side branching. The amount of contrast medium was determined and the effective radiation exposure of both methods was calculated. There was no significant difference regarding the vessel diameter of the great cardiac vein/anterior interventricular vein or its side branches. Also, estimation of vessel visibility was not different between the two imaging modalities. Estimated radiation exposure and amount of contrast medium were lower for rotational CSA. In conclusion, a 3D reconstruction of rotational CSA images is possible. All parts of the CVS are well depicted, allowing a 3D overview of the CVS anatomy. On-site 3D visualization might improve decision making during cardiac interventions. In contrast to DSCT, rotational CSA does not demonstrate the anatomy of the mitral annulus or the course of the left circumflex artery.

  3. Solving the problem of imaging resolution: stochastic multi-scale image fusion

    Science.gov (United States)

    Karsanina, Marina; Mallants, Dirk; Gilyazetdinova, Dina; Gerke, Kiril

    2016-04-01

    rocks) and RFBR grant 15-34-20989 (data fusion). References: 1. Karsanina, M.V., Gerke, K.M., Skvortsova, E.B., Mallants, D. Universal spatial correlation functions for describing and reconstructing soil microstructure. PLoS ONE 10(5): e0126515 (2015). 2. Gerke, K.M., Karsanina, M.V., Mallants, D. Universal stochastic multiscale image fusion: an example application for shale rock. Scientific Reports 5: 15880 (2015). 3. Gerke, K.M., Karsanina, M.V., Vasilyev, R.V., Mallants, D. Improving pattern reconstruction using correlation functions computed in directions. Europhys. Lett. 106(6), 66002 (2014). 4. Gerke, K.M., Karsanina, M.V. Improving stochastic reconstructions by weighting correlation functions in an objective function. Europhys. Lett. 111, 56002 (2015).

  4. CT and MR image fusion using two different methods after prostate brachytherapy: impact on post-implant dosimetric assessment

    International Nuclear Information System (INIS)

    Servois, V.; El Khoury, C.; Lantoine, A.; Ollivier, L.; Neuenschwander, S.; Chauveinc, L.; Cosset, J.M.; Flam, T.; Rosenwald, J.C.

    2003-01-01

    To study different methods of CT and MR images fusion in patient treated by brachytherapy for localized prostate cancer. To compare the results of the dosimetric study realized on CT slices and images fusion. Fourteen cases of patients treated by 1125 were retrospectively studied. The CT examinations were realized with continuous section of 5 mm thickness, and MR images were obtained with a surface coil with contiguous section of 3 mm thickness. For the images fusion process, only the T2 weighted MR sequence was used. Two processes of images fusion were realized for each patient, using as reference marks the bones of the pelvis and the implanted seeds. A quantitative and qualitative appreciation was made by the operators, for each patient and both methods of images fusion. The dosimetric study obtained by a dedicated software was realized on CT images and all types of images fusion. The usual dosimetric indexes (D90, V 100 and V 150) were compared for each type of image. The quantitative results given by the software of images fusion showed a superior accuracy to the one obtained by the pelvic bony reference marks. Conversely, qualitative and quantitative results obtained by the operators showed a better accuracy of the images fusion based on iodine seeds. For two patients out of three presenting a D90 inferior to 145 Gy on CT examination, the D90 was superior to this norm when the dosimetry was based on images fusion, whatever the method used. The images fusion method based on implanted seed matching seems to be more precise than the one using bony reference marks. The dosimetric study realized on images fusion could allow to rectify possible errors, mainly due to difficulties in surrounding prostate contour delimitation on CT images. (authors)

  5. Live-cell imaging of conidial anastomosis tube fusion during colony initiation in Fusarium oxysporum.

    Directory of Open Access Journals (Sweden)

    Smija M Kurian

    Full Text Available Fusarium oxysporum exhibits conidial anastomosis tube (CAT fusion during colony initiation to form networks of conidial germlings. Here we determined the optimal culture conditions for this fungus to undergo CAT fusion between microconidia in liquid medium. Extensive high resolution, confocal live-cell imaging was performed to characterise the different stages of CAT fusion, using genetically encoded fluorescent labelling and vital fluorescent organelle stains. CAT homing and fusion were found to be dependent on adhesion to the surface, in contrast to germ tube development which occurs in the absence of adhesion. Staining with fluorescently labelled concanavalin A indicated that the cell wall composition of CATs differs from that of microconidia and germ tubes. The movement of nuclei, mitochondria, vacuoles and lipid droplets through fused germlings was observed by live-cell imaging.

  6. Image fusion between whole body FDG PET images and whole body MRI images using a full-automatic mutual information-based multimodality image registration software

    International Nuclear Information System (INIS)

    Uchida, Yoshitaka; Nakano, Yoshitada; Fujibuchi, Toshiou; Isobe, Tomoko; Kazama, Toshiki; Ito, Hisao

    2006-01-01

    We attempted image fusion between whole body PET and whole body MRI of thirty patients using a full-automatic mutual information (MI) -based multimodality image registration software and evaluated accuracy of this method and impact of the coregistrated imaging on diagnostic accuracy. For 25 of 30 fused images in body area, translating gaps were within 6 mm in all axes and rotating gaps were within 2 degrees around all axes. In head and neck area, considerably much gaps caused by difference of head inclination at imaging occurred in 16 patients, however these gaps were able to decrease by fused separately. In 6 patients, diagnostic accuracy using PET/MRI fused images was superior compared by PET image alone. This work shows that whole body FDG PET images and whole body MRI images can be automatically fused using MI-based multimodality image registration software accurately and this technique can add useful information when evaluating FDG PET images. (author)

  7. Usefulness of CT based SPECT Fusion Image in the lung Disease : Preliminary Study

    International Nuclear Information System (INIS)

    Park, Hoon Hee; Lyu, Kwang Yeul; Kim, Tae Hyung; Shin, Ji Yun

    2012-01-01

    Recently, SPECT/CT system has been applied to many diseases, however, the application is not extensively applied at pulmonary disease. Especially, in case that, the pulmonary embolisms suspect at the CT images, SPECT is performed. For the accurate diagnosis, SPECT/CT tests are subsequently undergoing. However, without SPECT/CT, there are some limitations to apply these procedures. With SPECT/CT, although, most of the examination performed after CT. Moreover, such a test procedures generate unnecessary dual irradiation problem to the patient. In this study, we evaluated the amount of unnecessary irradiation, and the usefulness of fusion images of pulmonary disease, which independently acquired from SPECT and CT. Using NEMA PhantomTM (NU2-2001), SPECT and CT scan were performed for fusion images. From June 2011 to September 2010, 10 patients who didn't have other personal history, except lung disease were selected (male: 7, female: 3, mean age: 65.3±12.7). In both clinical patient and phantom data, the fusion images scored higher than SPECT and CT images. The fusion images, which is combined with pulmonary vessel images from CT and functional images from SPECT, can increase the detection possibility in detecting pulmonary embolism in the resin of lung parenchyma. It is sure that performing SPECT and CT in integral SPECT/CT system were better. However, we believe this protocol can give more informative data to have more accurate diagnosis in the hospital without integral SPECT/CT system.

  8. Mosaicing of single plane illumination microscopy images using groupwise registration and fast content-based image fusion

    Science.gov (United States)

    Preibisch, Stephan; Rohlfing, Torsten; Hasak, Michael P.; Tomancak, Pavel

    2008-03-01

    Single Plane Illumination Microscopy (SPIM; Huisken et al., Nature 305(5686):1007-1009, 2004) is an emerging microscopic technique that enables live imaging of large biological specimens in their entirety. By imaging the living biological sample from multiple angles SPIM has the potential to achieve isotropic resolution throughout even relatively large biological specimens. For every angle, however, only a relatively shallow section of the specimen is imaged with high resolution, whereas deeper regions appear increasingly blurred. In order to produce a single, uniformly high resolution image, we propose here an image mosaicing algorithm that combines state of the art groupwise image registration for alignment with content-based image fusion to prevent degrading of the fused image due to regional blurring of the input images. For the registration stage, we introduce an application-specific groupwise transformation model that incorporates per-image as well as groupwise transformation parameters. We also propose a new fusion algorithm based on Gaussian filters, which is substantially faster than fusion based on local image entropy. We demonstrate the performance of our mosaicing method on data acquired from living embryos of the fruit fly, Drosophila, using four and eight angle acquisitions.

  9. Image retrieval by information fusion based on scalable vocabulary tree and robust Hausdorff distance

    Science.gov (United States)

    Che, Chang; Yu, Xiaoyang; Sun, Xiaoming; Yu, Boyang

    2017-12-01

    In recent years, Scalable Vocabulary Tree (SVT) has been shown to be effective in image retrieval. However, for general images where the foreground is the object to be recognized while the background is cluttered, the performance of the current SVT framework is restricted. In this paper, a new image retrieval framework that incorporates a robust distance metric and information fusion is proposed, which improves the retrieval performance relative to the baseline SVT approach. First, the visual words that represent the background are diminished by using a robust Hausdorff distance between different images. Second, image matching results based on three image signature representations are fused, which enhances the retrieval precision. We conducted intensive experiments on small-scale to large-scale image datasets: Corel-9, Corel-48, and PKU-198, where the proposed Hausdorff metric and information fusion outperforms the state-of-the-art methods by about 13, 15, and 15%, respectively.

  10. Research on multi-source image fusion technology in haze environment

    Science.gov (United States)

    Ma, GuoDong; Piao, Yan; Li, Bing

    2017-11-01

    In the haze environment, the visible image collected by a single sensor can express the details of the shape, color and texture of the target very well, but because of the haze, the sharpness is low and some of the target subjects are lost; Because of the expression of thermal radiation and strong penetration ability, infrared image collected by a single sensor can clearly express the target subject, but it will lose detail information. Therefore, the multi-source image fusion method is proposed to exploit their respective advantages. Firstly, the improved Dark Channel Prior algorithm is used to preprocess the visible haze image. Secondly, the improved SURF algorithm is used to register the infrared image and the haze-free visible image. Finally, the weighted fusion algorithm based on information complementary is used to fuse the image. Experiments show that the proposed method can improve the clarity of the visible target and highlight the occluded infrared target for target recognition.

  11. Information fusion in signal and image processing major probabilistic and non-probabilistic numerical approaches

    CERN Document Server

    Bloch, Isabelle

    2010-01-01

    The area of information fusion has grown considerably during the last few years, leading to a rapid and impressive evolution. In such fast-moving times, it is important to take stock of the changes that have occurred. As such, this books offers an overview of the general principles and specificities of information fusion in signal and image processing, as well as covering the main numerical methods (probabilistic approaches, fuzzy sets and possibility theory and belief functions).

  12. Pre-operative CT angiography and three-dimensional image post processing for deep inferior epigastric perforator flap breast reconstructive surgery.

    Science.gov (United States)

    Lam, D L; Mitsumori, L M; Neligan, P C; Warren, B H; Shuman, W P; Dubinsky, T J

    2012-12-01

    Autologous breast reconstructive surgery with deep inferior epigastric artery (DIEA) perforator flaps has become the mainstay for breast reconstructive surgery. CT angiography and three-dimensional image post processing can depict the number, size, course and location of the DIEA perforating arteries for the pre-operative selection of the best artery to use for the tissue flap. Knowledge of the location and selection of the optimal perforating artery shortens operative times and decreases patient morbidity.

  13. Noncontrast magnetic resonance angiography of the hand: improved arterial conspicuity by multidirectional flow-sensitive dephasing magnetization preparation in 3D balanced steady-state free precession imaging.

    Science.gov (United States)

    Fan, Zhaoyang; Hodnett, Philip A; Davarpanah, Amir H; Scanlon, Timothy G; Sheehan, John J; Varga, John; Carr, James C; Li, Debiao

    2011-08-01

    : To develop a flow-sensitive dephasing (FSD) preparative scheme to facilitate multidirectional flow-signal suppression in 3-dimensional balanced steady-state free precession imaging and to validate the feasibility of the refined sequence for noncontrast magnetic resonance angiography (NC-MRA) of the hand. : A new FSD preparative scheme was developed that combines 2 conventional FSD modules. Studies using a flow phantom (gadolinium-doped water 15 cm/s) and the hands of 11 healthy volunteers (6 males and 5 females) were performed to compare the proposed FSD scheme with its conventional counterpart with respect to the signal suppression of multidirectional flow. In 9 of the 11 healthy subjects and 2 patients with suspected vasculitis and documented Raynaud phenomenon, respectively, 3-dimensional balanced steady-state free precession imaging coupled with the new FSD scheme was compared with spatial-resolution-matched (0.94 × 0.94 × 0.94 mm) contrast-enhanced magnetic resonance angiography (0.15 mmol/kg gadopentetate dimeglumine) in terms of overall image quality, venous contamination, motion degradation, and arterial conspicuity. : The proposed FSD scheme was able to suppress 2-dimensional flow signal in the flow phantom and hands and yielded significantly higher arterial conspicuity scores than the conventional scheme did on NC-MRA at the regions of common digitals and proper digitals. Compared with contrast-enhanced magnetic resonance angiography, the refined NC-MRA technique yielded comparable overall image quality and motion degradation, significantly less venous contamination, and significantly higher arterial conspicuity score at digital arteries. : The FSD-based NC-MRA technique is improved in the depiction of multidirectional flow by applying a 2-module FSD preparation, which enhances its potential to serve as an alternative magnetic resonance angiography technique for the assessment of hand vascular abnormalities.

  14. Adaptive structured dictionary learning for image fusion based on group-sparse-representation

    Science.gov (United States)

    Yang, Jiajie; Sun, Bin; Luo, Chengwei; Wu, Yuzhong; Xu, Limei

    2018-04-01

    Dictionary learning is the key process of sparse representation which is one of the most widely used image representation theories in image fusion. The existing dictionary learning method does not use the group structure information and the sparse coefficients well. In this paper, we propose a new adaptive structured dictionary learning algorithm and a l1-norm maximum fusion rule that innovatively utilizes grouped sparse coefficients to merge the images. In the dictionary learning algorithm, we do not need prior knowledge about any group structure of the dictionary. By using the characteristics of the dictionary in expressing the signal, our algorithm can automatically find the desired potential structure information that hidden in the dictionary. The fusion rule takes the physical meaning of the group structure dictionary, and makes activity-level judgement on the structure information when the images are being merged. Therefore, the fused image can retain more significant information. Comparisons have been made with several state-of-the-art dictionary learning methods and fusion rules. The experimental results demonstrate that, the dictionary learning algorithm and the fusion rule both outperform others in terms of several objective evaluation metrics.

  15. Detail-enhanced multimodality medical image fusion based on gradient minimization smoothing filter and shearing filter.

    Science.gov (United States)

    Liu, Xingbin; Mei, Wenbo; Du, Huiqian

    2018-02-13

    In this paper, a detail-enhanced multimodality medical image fusion algorithm is proposed by using proposed multi-scale joint decomposition framework (MJDF) and shearing filter (SF). The MJDF constructed with gradient minimization smoothing filter (GMSF) and Gaussian low-pass filter (GLF) is used to decompose source images into low-pass layers, edge layers, and detail layers at multiple scales. In order to highlight the detail information in the fused image, the edge layer and the detail layer in each scale are weighted combined into a detail-enhanced layer. As directional filter is effective in capturing salient information, so SF is applied to the detail-enhanced layer to extract geometrical features and obtain directional coefficients. Visual saliency map-based fusion rule is designed for fusing low-pass layers, and the sum of standard deviation is used as activity level measurement for directional coefficients fusion. The final fusion result is obtained by synthesizing the fused low-pass layers and directional coefficients. Experimental results show that the proposed method with shift-invariance, directional selectivity, and detail-enhanced property is efficient in preserving and enhancing detail information of multimodality medical images. Graphical abstract The detailed implementation of the proposed medical image fusion algorithm.

  16. Whole-Body MR Imaging Including Angiography: Predicting Recurrent Events in Diabetics.

    Science.gov (United States)

    Bertheau, Robert C; Bamberg, Fabian; Lochner, Elena; Findeisen, Hannes M; Parhofer, Klaus G; Kauczor, Hans-Ulrich; Schoenberg, Stefan O; Weckbach, Sabine; Schlett, Christopher L

    2016-05-01

    Whether whole-body MRI can predict occurrence of recurrent events in patients with diabetes mellitus. Whole-body MRI was prospectively applied to 61 diabetics and assessed for arteriosclerosis and ischemic cerebral/myocardial changes. Occurrence of cardiocerebral events and diabetic comorbidites was determined. Patients were stratified whether no, a single or recurrent events arose. As a secondary endpoint, events were stratified into organ system-specific groups. During a median follow-up of 70 months, 26 diabetics developed a total of 39 events; 18 (30%) developed one, 8 (13%) recurrent events. Between diabetics with no, a single and recurrent events, a stepwise higher burden was observed for presence of left ventricular (LV) hypo-/akinesia (3/28/75%, p < 0.0001), myocardial delayed-contrast-enhancement (17/33/63%, p = 0.001), carotid artery stenosis (11/17/63%, p = 0.005), peripheral artery stenosis (26/56/88%, p = 0.0006) and vessel score (1.00/1.30/1.76, p < 0.0001). After adjusting for clinical characteristics, LV hypo-/akinesia (hazard rate ratio = 6.57, p < 0.0001) and vessel score (hazard rate ratio = 12.29, p < 0.0001) remained independently associated. Assessing organ system risk, cardiac and cerebral MR findings predicted more strongly events in their respective organ system. Vessel-score predicted both cardiac and cerebral, but not non-cardiocerebral, events. Whole-body MR findings predict occurrence of recurrent events in diabetics independent of clinical characteristics, and may concurrently provide organ system-specific risk. • Patients with long-standing diabetes mellitus are at high risk for recurrent events. • Whole-body MRI predicts occurrence of recurrent events independently of clinical characteristics. • The vessel score derived from whole-body angiography is a good general risk-marker. • Whole-body MRI may also provide organ-specific risk assessment. • Current findings may indicate benefits of

  17. Label fusion based brain MR image segmentation via a latent selective model

    Science.gov (United States)

    Liu, Gang; Guo, Xiantang; Zhu, Kai; Liao, Hengxu

    2018-04-01

    Multi-atlas segmentation is an effective approach and increasingly popular for automatically labeling objects of interest in medical images. Recently, segmentation methods based on generative models and patch-based techniques have become the two principal branches of label fusion. However, these generative models and patch-based techniques are only loosely related, and the requirement for higher accuracy, faster segmentation, and robustness is always a great challenge. In this paper, we propose novel algorithm that combines the two branches using global weighted fusion strategy based on a patch latent selective model to perform segmentation of specific anatomical structures for human brain magnetic resonance (MR) images. In establishing this probabilistic model of label fusion between the target patch and patch dictionary, we explored the Kronecker delta function in the label prior, which is more suitable than other models, and designed a latent selective model as a membership prior to determine from which training patch the intensity and label of the target patch are generated at each spatial location. Because the image background is an equally important factor for segmentation, it is analyzed in label fusion procedure and we regard it as an isolated label to keep the same privilege between the background and the regions of interest. During label fusion with the global weighted fusion scheme, we use Bayesian inference and expectation maximization algorithm to estimate the labels of the target scan to produce the segmentation map. Experimental results indicate that the proposed algorithm is more accurate and robust than the other segmentation methods.

  18. Parametric Imaging Of Digital Subtraction Angiography Studies For Renal Transplant Evaluation

    Science.gov (United States)

    Gallagher, Joe H.; Meaney, Thomas F.; Flechner, Stuart M.; Novick, Andrew C.; Buonocore, Edward

    1981-11-01

    A noninvasive method for diagnosing acute tubular necrosis and rejection would be an important tool for the management of renal transplant patients. From a sequence of digital subtraction angiographic images acquired after an intravenous injection of radiographic contrast material, the parametric images of the maximum contrast, the time when the maximum contrast is reached, and two times the time at which one half of the maximum contrast is reached are computed. The parametric images of the time when the maximum is reached clearly distinguish normal from abnormal renal function. However, it is the parametric image of two times the time when one half of the maximum is reached which provides some assistance in differentiating acute tubular necrosis from rejection.

  19. Follow-up CT and CT angiography after intracranial aneurysm clipping and coiling - improved image quality by iterative metal artifact reduction

    Energy Technology Data Exchange (ETDEWEB)

    Bier, Georg; Hempel, Johann-Martin; Oergel, Anja; Hauser, Till-Karsten; Ernemann, Ulrike; Hennersdorf, Florian [Eberhard Karls University Tuebingen, Department of Diagnostic and Interventional Neuroradiology, Tuebingen (Germany); Bongers, Malte Niklas [Eberhard Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany)

    2017-07-15

    This paper aims to evaluate a new iterative metal artifact reduction algorithm for post-interventional evaluation of brain tissue and intracranial arteries. The data of 20 patients that underwent follow-up cranial CT and cranial CT angiography after clipping or coiling of an intracranial aneurysm was retrospectively analyzed. After the images were processed using a novel iterative metal artifact reduction algorithm, images with and without metal artifact reduction were qualitatively evaluated by two readers, using a five-point Likert scale. Moreover, artifact strength was quantitatively assessed in terms of CT attenuation and standard deviation alterations. The qualitative analysis yielded a significant increase in image quality (p = 0.0057) in iteratively processed images with substantial inter-observer agreement (k = 0.72), while the CTA image quality did not differ (p = 0.864) and even showed vessel contrast reduction in six cases (30%). The mean relative attenuation difference was 27% without metal artifact reduction vs. 11% for iterative metal artifact reduction images (p = 0.0003). The new iterative metal artifact reduction algorithm enhances non-enhanced CT image quality after clipping or coiling, but in CT-angiography images, the contrast of adjacent vessels can be compromised. (orig.)

  20. Follow-up CT and CT angiography after intracranial aneurysm clipping and coiling - improved image quality by iterative metal artifact reduction

    International Nuclear Information System (INIS)

    Bier, Georg; Hempel, Johann-Martin; Oergel, Anja; Hauser, Till-Karsten; Ernemann, Ulrike; Hennersdorf, Florian; Bongers, Malte Niklas

    2017-01-01

    This paper aims to evaluate a new iterative metal artifact reduction algorithm for post-interventional evaluation of brain tissue and intracranial arteries. The data of 20 patients that underwent follow-up cranial CT and cranial CT angiography after clipping or coiling of an intracranial aneurysm was retrospectively analyzed. After the images were processed using a novel iterative metal artifact reduction algorithm, images with and without metal artifact reduction were qualitatively evaluated by two readers, using a five-point Likert scale. Moreover, artifact strength was quantitatively assessed in terms of CT attenuation and standard deviation alterations. The qualitative analysis yielded a significant increase in image quality (p = 0.0057) in iteratively processed images with substantial inter-observer agreement (k = 0.72), while the CTA image quality did not differ (p = 0.864) and even showed vessel contrast reduction in six cases (30%). The mean relative attenuation difference was 27% without metal artifact reduction vs. 11% for iterative metal artifact reduction images (p = 0.0003). The new iterative metal artifact reduction algorithm enhances non-enhanced CT image quality after clipping or coiling, but in CT-angiography images, the contrast of adjacent vessels can be compromised. (orig.)